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The University of Warwick ) is a public research university in Coventry, England. It was founded in 1965 as part of a government initiative to expand access to higher education. Warwick Business School was established in 1967 and Warwick Medical School was opened in 2000. Warwick merged with Coventry College of Education in 1979 and Horticulture Research International in 2004.Warwick is primarily based on a 290 hectare campus on the outskirts of Coventry with a satellite campus in Wellesbourne and a London base at the Shard in central London. It is organised into four faculties—Arts, Medicine, Science and Social science—within which there are 32 departments. Warwick has around 23,400 full-time students and 1,390 academic and research staff and had a total income of £460 million in 2012/13, of which £84 million was from research grants and contracts. Warwick Arts Centre, a multi-venue arts complex in the university's main campus, is the largest venue of its kind in the UK outside London.Warwick consistently ranks in the top ten of all major national rankings of British universities and is the only multi-faculty institution aside from the Universities of Oxford, Cambridge, and Imperial to have never been ranked outside of the top ten. It is ranked by QS as the world's third best university under 50 years and as the world's 13th best university based on employer reputation. It was ranked 7th in the UK amongst multi-faculty institutions for the quality of its research in the 2014 Research Assessment Exercise. Entrance is competitive, with around 8.25 applicants per place for undergraduate study.Warwick is a member of AACSB, the Association of Commonwealth Universities, the Association of MBAs, EQUIS, the European University Association, the M5 Group, the Russell Group and Universities UK. It is the only European member of the Center for Urban Science and Progress, a collaboration with New York University. The university has extensive commercial activities, including the University of Warwick Science Park and Warwick Manufacturing Group. Wikipedia.

Barlow J.,University of Warwick
Cochrane database of systematic reviews (Online) | Year: 2011

Parenting programmes are a potentially important means of supporting teenage parents and improving outcomes for their children, and parenting support is a priority across most Western countries. This review updates the previous version published in 2001. To examine the effectiveness of parenting programmes in improving psychosocial outcomes for teenage parents and developmental outcomes in their children. We searched to find new studies for this updated review in January 2008 and May 2010 in CENTRAL, MEDLINE, EMBASE, ASSIA, CINAHL, DARE, ERIC, PsycINFO, Sociological Abstracts and Social Science Citation Index. The National Research Register (NRR) was last searched in May 2005 and UK Clinical Research Network Portfolio Database in May 2010. Randomised controlled trials assessing short-term parenting interventions aimed specifically at teenage parents and a control group (no-treatment, waiting list or treatment-as-usual). We assessed the risk of bias in each study. We standardised the treatment effect for each outcome in each study by dividing the mean difference in post-intervention scores between the intervention and control groups by the pooled standard deviation. We included eight studies with 513 participants, providing a total of 47 comparisons of outcome between intervention and control conditions. Nineteen comparisons were statistically significant, all favouring the intervention group. We conducted nine meta-analyses using data from four studies in total (each meta-analysis included data from two studies). Four meta-analyses showed statistically significant findings favouring the intervention group for the following outcomes: parent responsiveness to the child post-intervention (SMD -0.91, 95% CI -1.52 to -0.30, P = 0.04); infant responsiveness to mother at follow-up (SMD -0.65, 95% CI -1.25 to -0.06, P = 0.03); and an overall measure of parent-child interactions post-intervention (SMD -0.71, 95% CI -1.31 to -0.11, P = 0.02), and at follow-up (SMD -0.90, 95% CI -1.51 to -0.30, P = 0.004). The results of the remaining five meta-analyses were inconclusive. Variation in the measures used, the included populations and interventions, and the risk of bias within the included studies limit the conclusions that can be reached. The findings provide some evidence to suggest that parenting programmes may be effective in improving a number of aspects of parent-child interaction both in the short- and long-term, but further research is now needed.

Throsby K.,University of Warwick
Sociology of Health and Illness | Year: 2012

Drawing on ethnographic data gathered through observations and interviews at a surgical weight management clinic in a large hospital, this article argues that while the core values governing the provision of obesity surgery (obesity=ill health; obesity surgery=weight loss; weight loss=improved health and cost savings) can be seen as governing the clinical encounter, the singularity of these collective equations reflects neither the complexity of the patient experience of obesity surgery nor the extent to which the 'war on obesity' itself does not adhere strictly to those principles. Drawing on Annemarie Mol's concept of the body multiple, and focusing on three different forms of excess (excess weight, excess consumption and excess skin) that emerged in the course of the study, this article argues that the rationalised singularity of obesity that is enacted in the obesity surgery clinic risks obscuring the uncertainties inherent to those practices and the moral judgements and values that are ultimately inextricable from them. © 2011 The Author. Sociology of Health & Illness © 2011 Foundation for the Sociology of Health & Illness/Blackwell Publishing Ltd.

Fraser J.,Bristol Royal Hospital for Children | Sidebotham P.,University of Warwick | Frederick J.,Monash University | Covington T.,Review Centre | Mitchell E.A.,University of Auckland
The Lancet | Year: 2014

Despite pronounced reductions in child mortality in industrialised countries, variations exist within and between countries. Many child deaths are preventable, and much could be done to further reduce mortality. For the family, their community, and professionals caring for them, every child's death is a tragedy. Systematic review of all child deaths is grounded in respect for the rights of children and their families, and aimed towards the prevention of future child deaths. In a Series of three papers, we discuss child death in high-income countries in the context of evolving child death review processes. This paper outlines the background to and development of child death review in the USA, England, Australia, and New Zealand. We consider the purpose, process, and outputs of child death review, and discuss how these factors can contribute to a greater understanding of children's deaths and to knowledge for the prevention of future child deaths.

Arrowsmith S.,University of Liverpool | Wray S.,University of Liverpool | Quenby S.,University of Warwick
BJOG: An International Journal of Obstetrics and Gynaecology | Year: 2011

Objective: To investigate the effect of maternal obesity on mode of delivery following induction of labour (IOL) for prolonged pregnancy and subsequent intrapartum and neonatal complications. Design: Retrospective (historical) cohort study. Setting: Liverpool Women's Hospital NHS Foundation Trust, UK. Population: A total of 29 224 women with singleton pregnancies between 2004 and 2008 of whom 3076 had a prolonged pregnancy (defined as ≥290 days or 41 +3 weeks of gestation) and received IOL. Methods: Kruskal-Wallis test, chi-square test and multivariable logistic regression. Main outcome measures: Mode of delivery and risk of delivery and neonatal complications in obese verses non-obese women following IOL. Results: Obese women had a significantly higher rate of IOL ending in caesarean section compared with women of normal weight following IOL (38.7% versus 23.8% primiparous; 9.9% versus 7.9% multiparous women, respectively); however, length of labour, incidence of postpartum haemorrhage and third-degree tear, rate of low cord blood pH, low Apgar scores and shoulder dystocia were similar in all body mass index categories. Complications included a higher incidence of fetal macrosomia and second-degree, but not third-degree, tear in primiparous women. Conclusions: Higher maternal body mass index at booking is associated with an increased risk of prolonged pregnancy and increased rate of IOL. Despite this, more than 60% of obese primiparous and 90% of multiparous women with prolonged pregnancies who were induced achieved vaginal delivery and labour complications in the obese women with prolonged pregnancies were largely comparable to those of normal weight women with prolonged pregnancies. Our data suggest that IOL for prolonged pregnancy in obese women is a reasonable and safe management option. © 2011 The Authors Journal compilation © RCOG 2011 BJOG An International Journal of Obstetrics and Gynaecology.

Presented in this paper is a study to show that the Hart-Smith semiempirical modeling approach can be used to predict the net-tension strength of multirowed bolted connections of pultruded material. Using the original 1987 paper by Hart-Smith a strength equation is developed for the specific connection configuration of two rows with a centrally placed steel bolt. The reported equation can be directly used for the two orientations of material that have the tension load parallel or perpendicular to the direction of pultrusion. Using experimental measurements for material properties and single-bolted connections from Rosner's 1992 work and the open-hole tension strengths from Turvey and Wang's 2003 paper, representative values to the modeling parameters in the strength equation are established. For model verification a comparison is made between theoretical and experimental strengths, using 17 test results from Hassan et al.'s 1997a work. Only two of the 17 experimental-to-theory strength ratios are <1.0, and only one of these two could be said to have predicted unsafe net-tension strengths. With none of the ratios exceeding 1.2, it is seen that the simple and versatile modeling approach gives very acceptable predictions. To determine the modeling parameters that will enable the Hart-Smith approach to be in a load resistance factor design standard there is a need for a comprehensive series of strength tests, for net-tension failure with filled- and open-holes, that covers the complete range of multirowed bolted connections that is to be permitted by the standard. © 2010 ASCE.

Biktashev V.N.,University of Liverpool | Barkley D.,University of Warwick | Biktasheva I.V.,University of Liverpool
Physical Review Letters | Year: 2010

Spiral waves in active media react to small perturbations as particlelike objects. Here we apply asymptotic theory to the interaction of spiral waves with a localized inhomogeneity, which leads to a novel prediction: drift of the spiral rotation center along circular orbits around the inhomogeneity. The stationary orbits have fixed radii and alternating stability, determined by the properties of the bulk medium and the type of inhomogeneity, while the drift speed along an orbit depends on the strength of the inhomogeneity. Direct numerical simulations confirm the validity and robustness of the theoretical predictions and show that these unexpected effects should be observable in experiment. © 2010 The American Physical Society.

Mcdonald R.,University of Warwick
Sociology of Health and Illness | Year: 2014

Sociologists of professions draw on Weberian theories of closure. However they have tended to ignore Bourdieu's work, which rejects Weberian notions of class and status groups as distinct ideal types and sees these concepts as inextricably linked. Bourdieu emphasises the importance of a class-based habitus which generates orientations, inclinations and dispositions that organise practices and the perception of practice. For Bourdieu, because individuals perceive one another primarily through the status that attaches to their practices (through a symbolic veil of honour) they fail to perceive the real basis of these practices: the forms of capital that underlie the different habitus and enable their realisation. This article draws on interviews with 17 elite doctors appearing on a national (UK) radio show during which they choose eight discs to take to a desert island. According to Bourdieu, 'nothing more clearly affirms one's "class", nothing more infallibly classifies, than one's taste in music'. An analysis of the doctors' musical tastes and their mode of acquisition (largely, for these elites, via their family and education at independent schools), as well as other insights into their cultural capital reveals the importance of linking class and status when exploring professional status and prestige. © 2014 The Author.

Challis G.L.,University of Warwick
Journal of Industrial Microbiology and Biotechnology | Year: 2014

Streptomyces, and related genera of Actinobacteria, are renowned for their ability to produce antibiotics and other bioactive natural products with a wide range of applications in medicine and agriculture. Streptomyces coelicolor A3(2) is a model organism that has been used for more than five decades to study the genetic and biochemical basis for the production of bioactive metabolites. In 2002, the complete genome sequence of S. coelicolor was published. This greatly accelerated progress in understanding the biosynthesis of metabolites known or suspected to be produced by S. coelicolor and revealed that streptomycetes have far greater potential to produce bioactive natural products than suggested by classical bioassay-guided isolation studies. In this article, efforts to exploit the S. coelicolor genome sequence for the discovery of novel natural products and biosynthetic pathways are summarized. © 2013 Society for Industrial Microbiology and Biotechnology.

Bugg T.D.H.,University of Warwick
Chemistry and Biology | Year: 2014

In this issue of Chemistry & Biology, Thierbach and colleagues establish the chemical mechanism for a cofactor-independent dioxygenase enzyme, a member of a small group of enzymes that can activate dioxygen without requiring a metal ion or redox cofactor. © 2014 Elsevier Ltd. All rights reserved.

Tang A.W.,University of Liverpool | Alfirevic Z.,University of Liverpool | Quenby S.,University of Warwick
Human Reproduction | Year: 2011

Background: Peripheral natural killer (pNK) and uterine NK (uNK) cells have been associated with reproductive failure. We systematically reviewed the literature to assess whether numbers or activity of pNK or uNK cells predicted subsequent pregnancy and outcome. Methods: We searched the electronic MEDLINE database from 1950 to April 2010 for relevant publications by using MeSH terms 'natural killer cells', 'reproduction' and 'pregnancy complications'. We included studies that measured pre-pregnancy pNK and uNK cell numbers or activity in women with recurrent miscarriage (RM) or infertility, and reported subsequent pregnancy outcomes of miscarriage or failure to conceive after assisted reproductive technology (ART). Results: The search identified 783 publications and 12 fulfilled the inclusion criteria. There were too few women entered into the observational studies to assess whether high pNK cell percentages or activity predicted subsequent miscarriage in women with idiopathic RM (numbers: n=32, OR 17, 95 CI 0.82-350.6, activity: n=92, OR 2.51, 95 CI 0.16-40.29), or implantation failure (n 203, OR 1.35, 95 CI 0.28-6.46), or miscarriage in infertile women after ART (n=79, OR 2.48, 95 CI 0.50-12.32). Similarly, the studies of uNK cells were not large enough to assess whether abnormal uNK cell density predicted subsequent miscarriage in women with idiopathic RM (n=72, OR 1.33, 95 CI 0.16-11.11). None of the uNK cell studies in women with infertility reported pregnancy outcomes dichotomized for uNK cell numbers. Conclusions: The prognostic value of measuring pNK or uNK cell parameters remains uncertain. More studies are needed to confirm or refute the role of NK cell assessments as a predictive test for screening women who may benefit from immunotherapy. © 2011 The Author Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved.

Crafts N.,University of Warwick
Oxford Review of Economic Policy | Year: 2015

This paper considers developments in UK growth performance and supply-side policies since the 1980s. It argues that economic reforms made in the Thatcher years and consolidated under subsequent governments delivered improved pre-crisis growth outcomes helped by the information and communications technology (ICT) revolution and stronger competition in product markets. The new growth economics provided useful insights for policy-makers, some of which were partly heeded. Recently, as productivity growth has stalled, there has been a turn to 'soft' industrial policy and a fear that the future is one of secular stagnation. The former has made little difference and the latter is unlikely. © The Author 2015.

Mishima M.,University of Warwick
Seminars in Cell and Developmental Biology | Year: 2016

Cleavage furrow in animal cell cytokinesis is formed by cortical constriction driven by contraction of an actomyosin network activated by Rho GTPase. Although the role of the mitotic apparatus in furrow induction has been well established, there remain discussions about the detailed molecular mechanisms of the cleavage signaling. While experiments in large echinoderm embryos highlighted the role of astral microtubules, data in smaller cells indicate the role of central spindle. Centralspindlin is a constitutive heterotetramer of MKLP1 kinesin and the non-motor CYK4 subunit and plays crucial roles in formation of the central spindle and recruitment of the downstream cytokinesis factors including ECT2, the major activator of Rho during cytokinesis, to the site of division. Recent reports have revealed a role of this centralspindlin-ECT2 pathway in furrow induction both by the central spindle and by the astral microtubules. Here, a unified view of the stimulation of cortical contractility by this pathway is discussed.Cytokinesis, the division of the whole cytoplasm, is an essential process for cell proliferation and embryonic development. In animal cells, cytokinesis is executed using a contractile network of actin filaments driven by a myosin-II motor that constricts the cell cortex (cleavage furrow ingression) into a narrow channel between the two daughter cells, which is resolved by scission (abscission) [1-3]. The anaphase-specific organization of the mitotic apparatus (MA, spindle with chromosomes plus asters) positions the cleavage furrow and plays a major role in spatial coupling between mitosis and cytokinesis [4-6]. The nucleus and chromosomes are dispensable for furrow specification [7-10], although they contribute to persistent furrowing and robust completion in some cell types [11,12]. Likewise, centrosomes are not essential for cytokinesis, but they contribute to the general fidelity of cell division [10,13-15]. Here, classical models of cleavage furrow induction are outlined, and a unified view of the stimulation of cortical contractility by the centralspindlin-ECT2 pathway is discussed. © 2016 Elsevier Ltd.

Luskin M.,127 Vincent Hall | Ortner C.,University of Warwick | Van Koten B.,127 Vincent Hall
Computer Methods in Applied Mechanics and Engineering | Year: 2013

We formulate an energy-based atomistic-to-continuum coupling method based on blending the quasicontinuum method for the simulation of crystal defects. We utilize theoretical results from Van Koten and Luskin [32] and Ortner and Van Koten [24] to derive optimal choices of approximation parameters (blending function and finite element grid) for microcrack and di-vacancy test problems and confirm our analytical predictions in numerical tests. © 2012 Elsevier B.V.

Singh S.P.,University of Warwick | Harley K.,South London and Maudsley NHS Foundation Trust | Suhail K.,The University of Lahore
Schizophrenia Bulletin | Year: 2013

Understanding cross-cultural aspects of emotional overinvolvement (EOI) on psychosis outcomes is important for ensuring cultural appropriateness of family interventions. This systematic review explores whether EOI has similar impact in different cultural groups and whether the same norms can be used to measure EOI across cultures. Thirty-four studies were found that have investigated the impact of EOI on outcomes across cultures or culturally adapted EOI measures. The relationship between high EOI and poor outcome is inconsistent across cultures. Attempts to improve predictive ability by post hoc adjustment of EOI norms have had varied success. Few studies have attempted a priori adaptations or development of culture-specific norms. Methodological differences such as use of different expressed emotions (EE) measures and varying definitions of relapse across studies may explain a lack of EOI outcome relationship across cultures. However, our findings suggest that the construct and measurement of EOI itself are culture-specific. EOI may not necessarily be detrimental in all cultures. The effect of high EOI may be moderated by the unexplored dimension of warmth and high levels of mutual interdependence in kin relationships. Researchers should reevaluate the prevailing concepts of the impact of family relations on the course and outcome of psychotic disorders, specifically focusing on the protective aspects of family involvement. Clinically, family interventions based on EE reduction should take cultural differences into account when treating families from different ethnocultural groups. © 2013 The Author.

Li C.-T.,University of Warwick | Li Y.,Nankai University
IEEE Transactions on Circuits and Systems for Video Technology | Year: 2012

The last few years have seen the use of photo response non-uniformity noise (PRNU), a unique fingerprint of imaging sensors, in various digital forensic applications such as source device identification, content integrity verification, and authentication. However, the use of a color filter array for capturing only one of the three color components per pixel introduces color interpolation noise, while the existing methods for extracting PRNU provide no effective means for addressing this issue. Because the artificial colors obtained through the color interpolation process are not directly acquired from the scene by physical hardware, we expect that the PRNU extracted from the physical components, which are free from interpolation noise, should be more reliable than that from the artificial channels, which carry interpolation noise. Based on this assumption we propose a couple-decoupled PRNU (CD-PRNU) extraction method, which first decomposes each color channel into four sub-images and then extracts the PRNU noise from each sub-image. The PRNU noise patterns of the sub-images are then assembled to get the CD-PRNU. This new method can prevent the interpolation noise from propagating into the physical components, thus improving the accuracy of device identification and image content integrity verification. © 2011 IEEE.

Stallard N.,University of Warwick
Statistics in Medicine | Year: 2012

Methodology for sample size calculation for phase III clinical trials is well established and widely used. In contrast, for earlier phase clinical trials or pilot studies, although there is an acceptance that the methods used for phase III trials are not appropriate, there is little consensus over methods that should be used. This paper explores this problem from a Bayesian decision-theoretic perspective. The aim is to obtain sample sizes that would be appropriate for studies funded by a large funder such as a public sector body or major pharmaceutical company. The sample sizes obtained are optimal in that they minimise the average number of patients required per successfully identified effective therapy or equivalently maximise the number of effective therapies successfully identified over a long period. It is indicated that the number of patients included in a phase II clinical trial should be approximately 0.03 times that planned to be included in the phase III study. This is similar to that proposed by other researchers in this area, though rather smaller than actually used for many phase II trials. © 2011 John Wiley & Sons, Ltd.

Tiskin A.,University of Warwick
Proceedings of the Annual ACM-SIAM Symposium on Discrete Algorithms | Year: 2010

Monge matrices play a fundamental role in optimisation theory, graph and string algorithms. Distance multiplication of two Monge matrices of size n can be performed in time O(n2). Motivated by applications to string algorithms, we introduced in previous works a subclass of Monge matrices, that we call simple unit-Monge matrices. We also gave a distance multiplication algorithm for such matrices, running in time O(n1.5). Landau asked whether this problem can be solved in linear time. In the current work, we give an algorithm running in time O(n log n), thus approaching an answer to Landau's question within a logarithmic factor. The new algorithm implies immediate improvements in running time for a number of algorithms on strings and graphs. In particular, we obtain an algorithm for finding a maximum clique in a circle graph in time O(n log2 n), and a surprisingly efficient algorithm for comparing compressed strings. We also point to potential applications in group theory, by making a connection between unit-Monge matrices and Coxeter monoids. We conclude that unit-Monge matrices are a fascinating object and a powerful tool, that deserves further study from both the mathematical and the algorithmic viewpoints. Copyright © by SIAM.

Maylor E.A.,University of Warwick | Logie R.H.,University of Edinburgh
Quarterly Journal of Experimental Psychology | Year: 2010

We present the first large-scale comparison of prospective memory (PM) and retrospective memory (RM) from 8 to 50 years of age (N = 318,614). Participants in an Internet study were asked to remember to click on a smiley face (single-trial event-based PM test) and to indicate whether/where a picture had changed from study to test (single-trial RM test), in both cases after retention intervals filled with working-memory tests and questionnaires. Both PM and RM improved during childhood; however, whereas maximal PM was reached by teenagers, with approximately linear decline through the 20s-40s, RM continued to improve through the 20s and 30s. On both tests, females outperformed males and achieved maximal success at earlier ages. Strikingly, 10-11-year-old girls performed significantly better than females in their late 20s on the PM test. The presence of the smiley face at encoding and temporal uncertainty (expecting it "later" rather than at the "end" of the test) both benefited PM; these effects decreased and increased, respectively, from childhood to middle age. The findings demonstrate that in a cross-sectional study (a) developmental trajectories are qualitatively different between PM and RM, and (b) the relative influence of PM cues differs between younger and older ages. © 2009 The Experimental Psychology Society.

Countries often spend billions on university research. There is growing interest in how to assess whether that money is well spent. Is there an objective way to assess the quality of a nation's world-leading science? I suggest a method, and illustrate it with data on economics. Of 450 genuinely world-leading journal articles, the UK produced 10% and the rest of Europe slightly more. Interestingly, more than a quarter of these UK articles came from outside the best-known university departments. The proposed methodology could be applied to almost any academic discipline or nation. © 2009 Akadémiai Kiadó, Budapest, Hungary.

Kirkilionis M.,University of Warwick
Briefings in Bioinformatics | Year: 2010

We discuss and review different ways to map cellular components and their temporal interaction with other such components to different non-spatially explicit mathematical models. The essential choices made in the literature are between discrete and continuous state spaces, between rule and event-based state updates and between deterministic and stochastic series of such updates. The temporal modelling of cellular regulatory networks (dynamic network theory) is compared with static network approaches in two first introductory sections on general network modelling. We concentrate next on deterministic rate-based dynamic regulatory networks and their derivation. In the derivation, we include methods from multiscale analysis and also look at structured large particles, here called macromolecular machines. It is clear that mass-action systems and their derivatives, i.e. networks based on enzyme kinetics, play the most dominant role in the literature. The tools to analyse cellular reaction networks are without doubt most complete for mass-action systems. We devote a long section at the end of the review to make a comprehensive review of related tools and mathematical methods. The emphasis is to show how cellular reaction networks can be analysed with the help of different associated graphs and the dissection into modules, i.e. sub-networks. © The Author 2010. Published by Oxford University Press. For Permissions, please email: journals.permissions@oxfordjournals.org.

Baronchelli A.,Northeastern University | Ferrer-i-Cancho R.,Polytechnic University of Catalonia | Pastor-Satorras R.,Polytechnic University of Catalonia | Chater N.,University of Warwick | And 2 more authors.
Trends in Cognitive Sciences | Year: 2013

Networks of interconnected nodes have long played a key role in Cognitive Science, from artificial neural networks to spreading activation models of semantic memory. Recently, however, a new Network Science has been developed, providing insights into the emergence of global, system-scale properties in contexts as diverse as the Internet, metabolic reactions, and collaborations among scientists. Today, the inclusion of network theory into Cognitive Sciences, and the expansion of complex-systems science, promises to significantly change the way in which the organization and dynamics of cognitive and behavioral processes are understood. In this paper, we review recent contributions of network theory at different levels and domains within the Cognitive Sciences. © 2013 Elsevier Ltd.

Csoka E.,University of Warwick
Journal of Combinatorial Theory. Series B | Year: 2016

In the dense graph limit theory, the topology of the set of graphs is defined by the distribution of the subgraphs spanned by finite number of random vertices. Vera T. Sós proposed a question that if we consider only the number of edges in the spanned subgraphs, then whether it provides an equivalent definition. We show that the answer is positive on quasirandom graphs, and we prove a generalization of the statement. © 2015 Elsevier Inc.

Oswald A.J.,University of Warwick | Wu S.,Hamilton College
Science | Year: 2010

A huge research literature, across the behavioral and social sciences, uses information on individuals' subjective well-being. These are responses to questions - asked by survey interviewers or medical personnel - such as, "How happy do you feel on a scale from 1 to 4?" Yet there is little scientific evidence that such data are meaningful. This study examines a 2005-2008 Behavioral Risk Factor Surveillance System random sample of 1.3 million U.S. citizens. Life satisfaction in each U.S. state is measured. Across America, people's answers trace out the same pattern of quality of life as previously estimated, from solely nonsubjective data, in one branch of economics (so-called "compensating differentials" neoclassical theory, originally from Adam Smith). There is a state-by-state match (r = 0.6, P < 0.001) between subjective and objective well-being. This result has some potential to help to unify disciplines.

Morgan B.,University of Warwick
Journal of Instrumentation | Year: 2010

This paper presents an investigation of the use of interest point detection algorithms from image processing applied to reconstruction of interactions in high granularity tracking detectors. Their purpose is to extract keypoints from the data as input to higher level reconstruction algorithms, replacing the role of human operators in event selection and reconstruction guidance. Simulations of nμ+40 Ar → μ- + p events with a nμ energy of 0.7GeV in a small liquid argon time projection chamber are used as a concrete example of a modern high granularity tracking detector. Data from the simulations are used to characterize the localization of interest points to physical features and the efficiency of finding interest points associated with the primary vertex and track ends is measured at the chosen beam energy. A high degree of localization is found, with 93% of detected interest points found within 5mm of a physical feature at the simulated energy of 0.7GeV. Working in two 2D projections, the primary vertex and both track ends are found in both projections in 85% of events at 0.7GeV. It is also shown that delta electrons can be detected. © 2010 IOP Publishing Ltd and SISSA.

Covington J.A.,University of Warwick
Sensors (Basel, Switzerland) | Year: 2013

Bile acid diarrhoea (BAD) is a common disease that requires expensive imaging to diagnose. We have tested the efficacy of a new method to identify BAD, based on the detection of differences in volatile organic compounds (VOC) in urine headspace of BAD vs. ulcerative colitis and healthy controls. A total of 110 patients were recruited; 23 with BAD, 42 with ulcerative colitis (UC) and 45 controls. Patients with BAD also received standard imaging (Se75HCAT) for confirmation. Urine samples were collected and the headspace analysed using an AlphaMOS Fox 4000 electronic nose in combination with an Owlstone Lonestar Field Asymmetric Ion Mobility Spectrometer (FAIMS). A subset was also tested by gas chromatography, mass spectrometry (GCMS). Linear Discriminant Analysis (LDA) was used to explore both the electronic nose and FAIMS data. LDA showed statistical differences between the groups, with reclassification success rates (using an n-1 approach) at typically 83%. GCMS experiments confirmed these results and showed that patients with BAD had two chemical compounds, 2-propanol and acetamide, that were either not present or were in much reduced quantities in the ulcerative colitis and control samples. We believe that this work may lead to a new tool to diagnose BAD, which is cheaper, quicker and easier that current methods.

Pikhurko O.,University of Warwick
Journal of Combinatorial Theory. Series B | Year: 2013

Let l>k≥3. Let the k-graph Hl(k) be obtained from the complete 2-graph Kl(2) by enlarging each edge with a new set of k-2 vertices. Mubayi [A hypergraph extension of Turán's theorem, J. Combin. Theory Ser. B 96 (2006) 122-134] computed asymptotically the Turán function ex(n,Hl(k)). Here we determine the exact value of ex(n,Hl(k)) for all sufficiently large n, settling a conjecture of Mubayi. © 2012 Elsevier Inc.

Smith N.A.,University of Warwick
Philosophical transactions. Series A, Mathematical, physical, and engineering sciences | Year: 2013

This short review highlights some of the exciting new experimental and theoretical developments in the field of photoactivatable metal complexes and their applications in biotechnology and medicine. The examples chosen are based on some of the presentations at the Royal Society Discussion Meeting in June 2012, many of which are featured in more detail in other articles in this issue. This is a young field. Even the photochemistry of well-known systems such as metal-carbonyl complexes is still being elucidated. Striking are the recent developments in theory and computation (e.g. time-dependent density functional theory) and in ultrafast-pulsed radiation techniques which allow photochemical reactions to be followed and their mechanisms to be revealed on picosecond/nanosecond time scales. Not only do some metal complexes (e.g. those of Ru and Ir) possess favourable emission properties which allow functional imaging of cells and tissues (e.g. DNA interactions), but metal complexes can also provide spatially controlled photorelease of bioactive small molecules (e.g. CO and NO)--a novel strategy for site-directed therapy. This extends to cancer therapy, where metal-based precursors offer the prospect of generating excited-state drugs with new mechanisms of action that complement and augment those of current organic photosensitizers.

Sutcliffe P.,University of Warwick
Health technology assessment (Winchester, England) | Year: 2013

Prophylactic aspirin has been considered to be beneficial in reducing the risks of heart disease and cancer. However, potential benefits must be balanced against the possible harm from side effects, such as bleeding and gastrointestinal (GI) symptoms. It is particularly important to know the risk of side effects when aspirin is used as primary prevention--that is when used by people as yet free of, but at risk of developing, cardiovascular disease (CVD) or cancer. In this report we aim to identify and re-analyse randomised controlled trials (RCTs), systematic reviews and meta-analyses to summarise the current scientific evidence with a focus on possible harms of prophylactic from regular aspirin use in primary prevention of CVD. Effects on cancer prevention have a long lead time and are at present reliant on post hoc analyses. All absolute effects are relatively small compared with the burden of these diseases. Several potentially relevant ongoing trials will be completed between 2013 and 2019, which may clarify the extent of benefit of aspirin in reducing cancer incidence and mortality. Future research considerations include expanding the use of IPD meta-analysis of RCTs by pooling data from available studies and investigating the impact of different dose regimens on cardiovascular and cancer outcomes. The National Institute for Health Research Health Technology Assessment programme.

Habershon S.,University of Warwick
Physical Chemistry Chemical Physics | Year: 2014

By comparing classical and quantum-mechanical (path-integral-based) molecular simulations of solvated halide anions X- [X = F, Cl, Br and I], we identify an ion-specific quantum contribution to anion-water hydrogen-bond dynamics; this effect has not been identified in previous simulation studies. For anions such as fluoride, which strongly bind water molecules in the first solvation shell, quantum simulations exhibit hydrogen-bond dynamics nearly 40% faster than the corresponding classical results, whereas those anions which form a weakly bound solvation shell, such as iodide, exhibit a quantum effect of around 10%. This observation can be rationalized by considering the different zero-point energy (ZPE) of the water vibrational modes in the first solvation shell; for strongly binding anions, the ZPE of bound water molecules is larger, giving rise to faster dynamics in quantum simulations. These results are consistent with experimental investigations of anion-bound water vibrational and reorientational motion. This journal is © the Partner Organisations 2014.

Macpherson J.V.,University of Warwick
Physical Chemistry Chemical Physics | Year: 2015

Conducting, boron doped diamond (BDD), in addition to its superior material properties, offers several notable attributes to the electrochemist making it an intriguing material for electrochemical research. These include the widest solvent window of all electrode materials; low background and capacitive currents; reduced fouling compared to other electrodes and; the ability to withstand extreme potentials, corrosive and high temperature/pressure environments. However, BDD is not your typical electrode material, it is a semi-conductor doped degenerately with boron to present semi-metallic characteristics. Input from materials scientists, chemists and physicists has been required to aid understanding of how to work with this material from an electrochemical viewpoint and improve electrode quality. Importantly, depending on how the BDD has been grown and then subsequently treated, prior to electrochemical measurement, the resulting material properties can vary quite significantly from one electrode to the next. This likely explains the variability seen by different researchers working on the same experimental systems. The aim of this "protocols" article is not to provide a state-of-the-art review of diamond electrochemistry, suitable references are provided to the interested reader, but instead serves as a reference point for any researcher wishing to commence work with diamond electrodes and interpret electrochemical data. It provides information on how best to characterise the material properties of the electrode before use and outlines the interplay between boron dopant density, non-diamond-carbon content, grain morphology, surface chemistry and redox couple identity. All should ideally be considered when interpretating electrochemical data arising from the diamond electrode. This will aid the reader in making meaningful comparisons between data obtained by different researchers using different diamond electrodes. The guide also aims to help educate the researcher in choosing which form of BDD is best suited to their research application. © the Owner Societies 2015.

Girao Coelho A.M.,University of Warwick
Archives of Computational Methods in Engineering | Year: 2015

The focus of this paper is on the computational modelling of progressive damage in composite structures of fibre reinforced laminae. A general review of modelling approaches to failure in the context of the finite element method is first presented, with an emphasis on models based on continuum damage mechanics. The way in which delamination and matrix splitting (that may or may not interact with fibre-tension damage) should be addressed in the framework of a commercial finite element code is considered next. An important feature of the analysis is it does not rely on customized user-subroutines but solely on the analysis capabilities of the general purpose software Abaqus, thus ensuring that the numerical results can be universally reproduced. It is shown that the finite element simulations can accurately represent the physical mechanisms controlling damage development and progression and reproduce a number of phenomena including delamination, laminate in-plane failure and behaviour at notches. The paper ends giving guidelines for the generalized modelling methodology using Abaqus without user-subroutines. © 2015 CIMNE, Barcelona, Spain

Stewart-Brown S.L.,University of Warwick
British Journal of Psychiatry | Year: 2015

The Chief Medical Officer's report for 2013 was the first of its kind to highlight the public's mental rather than physical health and thus represents a very important landmark for public health in the UK. Written primarily from the perspective of psychiatrists, the report has created confusion in public health circles by failing to adequately address the public health perspective. David Foreman's editorial in this issue, calling as it does for more training in public health for psychiatrists, is therefore very welcome and timely. © The Royal College of Psychiatrists 2015.

Grant W.,University of Warwick
Journal of Health Politics, Policy and Law | Year: 2012

Food and agricultural policy is an essential element of a communicable disease policy. The European Union has developed a more systematic and broadly based interest in questions of food safety and animal health and welfare linked to modernization of the Common Agricultural Policy, reflected in a new treaty obligation on animal welfare. Following the bovine spongiform encephalopathy crisis, moves were made to create a European competency, but implementation and enforcement resources reside with the member states. The European Animal Health Strategy is meant to lead to an EU animal health law, but this has already been constrained by fiscal austerity. The development of such a law may lead to a lowest common denominator formula that does little to enhance consumer protection or improve animal welfare. This is an inherent risk with top-down forms of Europeanization; more attention should be paid to lessons to be learned from bottom-up initiatives of the type used to counteract the bovine diarrhea virus. There will always be a tension among what is good policy for reducing the incidence of communicable disease, policy that is popular with EU citizens, and policy that is acceptable to member states. © 2012 by Duke University Press.

Sun H.,Durham University | Nallanathan A.,Kings College London | Wang C.-X.,Heriot - Watt University | Chen Y.,University of Warwick
IEEE Wireless Communications | Year: 2013

Cognitive radio has emerged as one of the most promising candidate solutions to improve spectrum utilization in next generation cellular networks. A crucial requirement for future cognitive radio networks is wideband spectrum sensing: secondary users reliably detect spectral opportunities across a wide frequency range. In this article, various wideband spectrum sensing algorithms are presented, together with a discussion of the pros and cons of each algorithm and the challenging issues. Special attention is paid to the use of sub-Nyquist techniques, including compressive sensing and multichannel sub-Nyquist sampling techniques. © 2002-2012 IEEE.

Francis L.J.,University of Warwick
Mental Health, Religion and Culture | Year: 2012

The SIFT method of biblical hermeneutics and liturgical preaching has its roots in Jungian psychological type theory and maintains that the reading and interpretation of text is shaped by individual preferences within the perceiving process (sensing and intuition) and within the evaluating process (thinking and feeling). The present study tests the empirical foundation for this method by examining the way in which three groups of participants familiar with handling scripture (N = 31, 14, and 47) interpret the Marcan narrative concerning the cleansing of the temple and the cursing of the fig tree. The data provide further support for the psychological principles underpinning the SIFT method. © 2012 Copyright Taylor and Francis Group, LLC.

Young D.,Adult Intensive Care Unit | Young D.,University of Oxford | Lamb S.E.,University of Oxford | Shah S.,Royal Infirmary | And 5 more authors.
New England Journal of Medicine | Year: 2013

BACKGROUND: Patients with the acute respiratory distress syndrome (ARDS) require mechanical ventilation to maintain arterial oxygenation, but this treatment may produce secondary lung injury. High-frequency oscillatory ventilation (HFOV) may reduce this secondary damage. METHODS: In a multicenter study, we randomly assigned adults requiring mechanical ventilation for ARDS to undergo either HFOV with a Novalung R100 ventilator (Metran) or usual ventilatory care. All the patients had a ratio of the partial pressure of arterial oxygen (PaO2) to the fraction of inspired oxygen (FIO 2) of 200 mm Hg (26.7 kPa) or less and an expected duration of ventilation of at least 2 days. The primary outcome was all-cause mortality 30 days after randomization. RESULTS: There was no significant between-group difference in the primary outcome, which occurred in 166 of 398 patients (41.7%) in the HFOV group and 163 of 397 patients (41.1%) in the conventional- ventilation group (P=0.85 by the chi-square test). After adjustment for study center, sex, score on the Acute Physiology and Chronic Health Evaluation (APACHE) II, and the initial PaO2:FIO2 ratio, the odds ratio for survival in the conventional-ventilation group was 1.03 (95% confidence interval, 0.75 to 1.40; P=0.87 by logistic regression). CONCLUSIONS: The use of HFOV had no significant effect on 30-day mortality in patients undergoing mechanical ventilation for ARDS. (Funded by the National Institute for Health Research Health Technology Assessment Programme; OSCAR Current Controlled Trials number, ISRCTN10416500.) Copyright © 2013 Massachusetts Medical Society. All rights reserved.

Eldridge J.J.,University of Cambridge | Stanway E.R.,H H Wills Physics Laboratory | Stanway E.R.,University of Warwick
Monthly Notices of the Royal Astronomical Society | Year: 2012

Young, massive stars dominate the rest-frame ultraviolet (UV) spectra of star-forming galaxies. At high redshifts (z> 2), these rest-frame UV features are shifted into the observed-frame optical and a combination of gravitational lensing, deep spectroscopy and spectral stacking analysis allows the stellar population characteristics of these sources to be investigated. We use our stellar population synthesis code Binary Population and Spectral Synthesis (bpass) to fit two strong rest-frame UV spectral features in published Lyman-break galaxy spectra, taking into account the effects of binary evolution on the stellar spectrum. In particular, we consider the effects of quasi-homogeneous evolution (arising from the rotational mixing of rapidly rotating stars), metallicity and the relative abundance of carbon and oxygen on the observed strengths of Heiiλ1640Å and Civλ1548, 1551Å spectral lines. We find that Lyman-break galaxy spectra atz~ 2-3 are best fitted with moderately sub-solar metallicities, and with a depleted carbon-to-oxygen ratio. We also find that the spectra of the lowest metallicity sources are best fitted with model spectra in which the Heii emission line is boosted by the inclusion of the effect of massive stars being spun-up during binary mass transfer so these rapidly rotating stars experience quasi-homogeneous evolution. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS.

Antolin P.,University of Oslo | Verwichte E.,University of Warwick
Astrophysical Journal | Year: 2011

The condensations composing coronal rain, falling down along loop-like structures observed in cool chromospheric lines such as Hα and Ca II H, have long been a spectacular phenomenon of the solar corona. However, considered a peculiar sporadic phenomenon, it has not received much attention. This picture is rapidly changing due to recent high-resolution observations with instruments such as the Hinode/Solar Optical Telescope (SOT), CRISP of the Swedish 1-m Solar Telescope, and the Solar Dynamics Observatory. Furthermore, numerical simulations have shown that coronal rain is the loss of thermal equilibrium of loops linked to footpoint heating. This result has highlighted the importance that coronal rain can play in the field of coronal heating. In this work, we further stress the importance of coronal rain by showing the role it can play in the understanding of the coronal magnetic field topology. We analyze Hinode/SOT observations in the Ca II H line of a loop in which coronal rain puts in evidence in-phase transverse oscillations of multiple strand-like structures. The periods, amplitudes, transverse velocities, and phase velocities are calculated, allowing an estimation of the energy flux of the wave and the coronal magnetic field inside the loop through means of coronal seismology. We discuss the possible interpretations of the wave as either standing or propagating torsional Alfvén or fast kink waves. An estimate of the plasma beta parameter of the condensations indicates a condition that may allow the often observed separation and elongation processes of the condensations. We also show that the wave pressure from the transverse wave can be responsible for the observed low downward acceleration of coronal rain. © 2011. The American Astronomical Society. All rights reserved.

Cheung D.L.,University of Warwick
Langmuir | Year: 2012

Hydrophobins are small, amphiphilic proteins expressed by strains of filamentous fungi. They fulfill a number of biological functions, often related to adsorption at hydrophobic interfaces, and have been investigated for a number of applications in materials science and biotechnology. In order to understand the biological function and applications of these proteins, a microscopic picture of the adsorption of these proteins at interfaces is needed. Using molecular dynamics simulations with a chemically detailed coarse-grained potential, the behavior of typical hydrophobins at the water-octane interface is studied. Calculation of the interfacial adsorption strengths indicates that the adsorption is essentially irreversible, with adsorption strengths of the order of 100 k BT (comparable to values determined for synthetic nanoparticles but significantly larger than small molecule surfactants and biomolecules). The protein structure at the interface is unchanged at the interface, which is consistent with the biological function of these proteins. Comparison of native proteins with pseudoproteins that consist of uniform particles shows that the surface structure of these proteins has a large effect on the interfacial adsorption strengths, as does the flexibility of the protein. © 2012 American Chemical Society.

Kerr R.M.,University of Warwick
Physics of Fluids | Year: 2013

Long, straight, anti-parallel vortex tubes, with balanced profiles and a local perturbation, are simulated using the Navier-Stokes equations and evolve into a chain of spiral vortex rings with the characteristics of three-dimensional turbulence. This includes evidence of a cascade of energy to high wavenumbers, the formation of a k-5/3 inertial subrange and a new hierarchy of rescaled vorticity moments where, against expectations, the lower-order moments bound the higher-order moments. This order holds for all times even as the individual moments fluctuate significantly and could explain the observation that ratios converge faster than the individual moments in very high Reynolds number forced turbulence simulations. The transformation of the original pair of vortices into turbulent swirling vortex rings is outlined by describing first the twists and turns of the first two reconnection steps in detail, next how these create the first set of vortex rings, and finally the formation of the additional reconnections and stretched, swirling rings that lead to turbulence. The k-5/3 spectrum is interpreted in terms of a model of stretched, spiral vortices similar to those seen in these simulations. © 2013 AIP Publishing LLC.

Gilbert E.,Caludon Center | Marwaha S.,University of Warwick
Journal of Affective Disorders | Year: 2013

Background: Severe work impairment can be present for a considerable proportion of the course of bipolar disorder (BD) and is costly for governments, services and individuals. Understanding predictors of employment in BD is therefore crucial as some may be susceptible to interventions. We conducted a systematic review of prospective studies in order to identify predictors of employment in people with BD. Methods: We searched Medline, PsychInfo, EMBASE and Web of Science databases, hand searched 3 journals and used predetermined criteria to select papers for full text inclusion. Sixty seven papers were identified. Nine met inclusion criteria, with a total sample of 3184. Results: Studies included in this review identified cognitive deficits (67%, n=4), depression (43%, n=3) and level of education (33%, n=2) as predictors of employment in BD patients. Bipolar depression not only affects whether someone is employed but also time off work. Even sub-syndromal depression appears to damage employment prospects. Verbal memory and executive functioning appear to be predictors of work functioning. Limitations: Conclusions are based on a relatively small number of studies and are therefore subject to change with the addition of further studies. A formal meta-regression was not possible due to differences between measures of employment and work functioning. Conclusions: Better assessment and management of depression and cognitive difficulties could improve the occupational functioning of BD patients. There is a need for high quality longitudinal studies specifically designed to investigate predictors of employment in large bipolar disorder samples. © 2012 Elsevier B.V. All rights reserved.

Tuckerman L.S.,University Paris Diderot | Barkley D.,University of Warwick
Physics of Fluids | Year: 2011

Near transition, plane Couette flow takes the form of large-scale, oblique, and statistically steady alternating bands of turbulent and laminar flow. Properties of these flows are investigated using direct numerical simulation in a tilted computational domain. Four regimes-uniform, intermittent, periodic, and localized-are characterized. The Fourier spectrum along the direction of variation of the pattern is presented, and the component corresponding to the pattern wavenumber is investigated as an order parameter. The mean flow of a periodic pattern is characterized and shown to lead to a relation between the Reynolds number and the wavelength and angle of a pattern. © 2011 American Institute of Physics.

Hudson T.,University of Oxford | Ortner C.,University of Warwick
Archive for Rational Mechanics and Analysis | Year: 2014

We formulate a variational model for a geometrically necessary screw dislocation in an anti-plane lattice model at zero temperature. Invariance of the energy functional under lattice symmetries renders the problem non-coercive. Nevertheless, by establishing coercivity with respect to the elastic strain and a concentration compactness principle, we prove the existence of a global energy minimizer and thus demonstrate that dislocations are globally stable equilibria within our model. © 2014 Springer-Verlag Berlin Heidelberg.

Dowler E.A.,University of Warwick | O'Connor D.,University College Dublin
Social Science and Medicine | Year: 2012

Food poverty is an important contributing factor to health inequalities in industrialised countries; it refers to the inability to acquire or eat an adequate quality or sufficient quantity of food in socially acceptable ways (or the uncertainty of being able to do so). Synonymous with household food insecurity, the issue needs to be located within a social justice framework. Recognising the clear interdependence between the right to food and the right to health, this paper explores how international human rights obligations could inform approaches to addressing food poverty and insecurity with specific reference to Ireland and the UK. Little attention has been paid to how countries should meet their obligations to respect, protect and fulfil the right to food in developed countries. The paper contributes by examining the social and policy circumstances which inhibit poor households from obtaining sufficient food to eat healthily, along with strategies and interventions from State and civil society actors in the two countries. In practice, problems and potential solutions have largely been directed towards the individual rather than at social determinants, particularly as research on environmental factors such as distance to shops has produced equivocal results. Other key structural aspects such as income sufficiency for food are broadly ignored by the State, and anti-poverty strategies are often implemented without monitoring for effects on food outcomes. Thus scant evidence exists for either Ireland or the UK meeting its rights to food obligations to date, in terms of roles and responsibilities in ensuring access to affordable, available and appropriate food for all. © 2011 Elsevier Ltd.

Podinovski V.V.,University of Warwick | Forsund F.R.,University of Oslo
Operations Research | Year: 2010

The implicit definition and nondifferentiability of efficient frontiers used in data envelopment analysis are two major obstacles to obtaining their differential characteristics, including various elasticity measures and marginal rates of substitution. In this paper we invoke the theorem of the directional derivative of the optimal value function and show how this can be used to define and calculate the required elasticities without any simplifying assumptions. This approach allows us to extend the known elasticity measures and introduce new ones to the entire efficient frontier, including all its extreme points, in one single development. We also construct linear programs that are required for the calculation of elasticity measures. Our main development is undertaken in the variable returns-to-scale technology but extends to other polyhedral technologies of efficiency analysis. © 2010 INFORMS.

Gershon T.,University of Warwick
Journal of Physics G: Nuclear and Particle Physics | Year: 2011

The recent measurement of an anomalous like-sign dimuon asymmetry by the D0 collaboration has prompted theoretical speculation on possible sources of physics beyond the standard model that may affect lifetimes and lifetime differences in neutral B meson systems. One observable that deserves closer attention is the width difference in the Bd 0 system, ΔΛd. Since the standard model prediction for this quantity is well below 1%, it serves as a 'null test' whereby the measurement of a larger value would cleanly reveal the presence of new physics. Methods to measure ΔΛd at current and future experiments are reviewed and an attractive new approach is proposed. © 2011 IOP Publishing Ltd.

Loomes G.,University of Warwick
Psychological Review | Year: 2014

Guo and Regenwetter (2014) took the perceived relative argument model, added various auxiliary assumptions of their own about the utility of money, made assumptions about possible stochastic specifications, and tested the various combined models against data from an experiment they conducted. However, their modeling assumptions were questionable and their experiment was unsatisfactory: The stimuli omitted crucial information, the incentives were weak, and the task load was excessive. These shortcomings undermine the quality of the data, and the study provides no new information about the scope and limitations of the perceived relative argument model or its performance relative to other models of risky choice. © 2014 American Psychological Association.

Crocioni P.,University of Warwick
Telecommunications Policy | Year: 2011

Net Neutrality has become the focus of attention in the regulatory debate on the Internet. This article attempts to strip down the debate to its bare essential. It identifies two main types of Net Neutrality obligations that have been put forward and assesses what type of potential concerns they may be designed to address. It concludes that while some of these concerns may be important it remains doubtful (at least in Europe) that an ex ante per se rule, such as those proposed under the Net Neutrality term, is the best way to address them. © 2010 Elsevier Ltd. All rights reserved.

Georgakopoulos A.,University of Warwick
European Journal of Combinatorics | Year: 2014

We prove that a Cayley graphcan be embedded in the Euclidean plane without accumulation points of vertices if and only ifit is the 1-skeleton of a Cayley complex that can be embedded in the plane after removing redundant simplices. We also give a characterisation of these Cayley graphs in term of group presentations, and deduce that they can be effectively enumerated. © 2013 Elsevier Ltd.

The best clinical decisions are based on both evidence and values in what is known as the 'two-feet principle'. Anecdotally, educationalists find teaching clinicians to become more evidence based is relatively simple in comparison to encouraging them to become more values based. One reason is likely to be the importance of values awareness. As values-based practice is premised on a mutual respect for the diversity of values, clinicians need to develop the skills to ascertain patient values and to get in touch with their own beliefs and preferences in order to understand those at play in any consultation. Only then can shared decision-making processes take place within a shared framework of values. In a research article published in BMC Medicine, Altamirano-Bustamante and colleagues highlight difficulties that clinicians face in getting in touch with their own values. Despite finding that healthcare personnel's core values were honesty and respect, autonomy was initially low ranked by participants. One significant aspect of this work is that this group has demonstrated that the extent to which clinicians value 'autonomy' and 'openness to change' can both be positively influenced by well designed education. © 2013 Peile; licensee BioMed Central Ltd.

Ostrovski G.,University of Warwick
Physica D: Nonlinear Phenomena | Year: 2014

We present a one-parameter family of continuous, piecewise affine, area preserving maps of the square, which are inspired by a dynamical system in game theory. Interested in the coexistence of stochastic and (quasi-)periodic behaviour, we investigate invariant annuli separated by invariant circles. For certain parameter values, we explicitly construct invariant circles both of rational and irrational rotation numbers, and present numerical experiments of the dynamics on the annuli bounded by these circles. © 2013 Elsevier B.V. All rights reserved.

Troisi A.,University of Warwick
Physical Review B - Condensed Matter and Materials Physics | Year: 2010

It is shown that dynamic localization of the charge carrier is present in the simple Holstein Hamiltonian (fully quantum and without random variables) if the polaron binding energy is sufficiently small and the small polaron is not formed at high temperature. Previously, this idea was only explored in semiclassical models of organic semiconductors. Band renormalization cannot be used in the presence of dynamic localization, which is best studied with a vibronic basis set introduced here. The lifetime of these vibronic states can be estimated using second-order renormalized perturbation theory. In the regime of dynamic localization the diffusivity displays a transition between metal-like and insulator-like transport as the temperature increases, similar to that predicted and observed in the nonadiabatic regime. © 2010 The American Physical Society.

Lloyd-Hughes J.,University of Warwick
Journal of Physics D: Applied Physics | Year: 2014

Terahertz time-domain spectroscopy permits the coherent motion of charges to be examined in a diverse range of two-dimensional semiconductor heterostructures. Studies of the THz conductivity and magnetoconductivity of two-dimensional quantum systems are reviewed, including cyclotron resonance spectroscopy and the transverse conductivity in the Hall and quantum Hall regimes. Experiments are described that demonstrate quantum phenomena at THz frequencies, principally coherent control and enhanced light-matter coupling in electromagnetic cavities. © 2014 IOP Publishing Ltd.

Blindauer C.A.,University of Warwick
Journal of Biological Inorganic Chemistry | Year: 2011

Bacterial metallothioneins (MTs) have been known since the mid-1980s. The only family known until recently was the BmtA family, exemplified by the zincand cadmium-binding SmtA from the cyanobacterium Synechococcus PCC 7942, for which a structure was determined in 2001. Only in 2008 was a second type of bacterial MT identified in mycobacteria, and the copperbinding gene product was called MymT. Many of the features of SmtA either have been unexpected or are otherwise "unusual", for example the presence of a zinc finger fold and the kinetic inertness of one of the four zinc ions bound to the protein. The unpredictability of molecular properties of this protein exemplified the need for continued biophysical studies of novel proteins. Homologues for SmtA have been identified in a limited number of bacterial genomes from cyanobacteria, pseudomonads, alphaproteobacteria, gammaproteobacteria, and firmicutes. Except for the residues defining the zinc finger fold, these homologous protein sequences display an intriguing variety, especially in terms of metal ligand position and identity. The increased number of homologues has allowed use of hidden Markov models to look for more remote relatives of SmtA, leading to the identification of a novel family of putative hybrid LIM domain MTs. However, database searches based on sequence similarity are of limited use for mining for further "overlooked" bacterial MTs, as so far undiscovered bacterial MTs may be too diverse from any other known MTs, and other approaches are required. © SBIC 2011.

Loman N.J.,University of Birmingham | Pallen M.J.,University of Warwick
Nature Reviews Microbiology | Year: 2015

Twenty years ago, the publication of the first bacterial genome sequence, from Haemophilus influenzae, shook the world of bacteriology. In this Timeline, we review the first two decades of bacterial genome sequencing, which have been marked by three revolutions: whole-genome shotgun sequencing, high-throughput sequencing and single-molecule long-read sequencing. We summarize the social history of sequencing and its impact on our understanding of the biology, diversity and evolution of bacteria, while also highlighting spin-offs and translational impact in the clinic. We look forward to a 'sequencing singularity', where sequencing becomes the method of choice for as-yet unthinkable applications in bacteriology and beyond. © 2015 Macmillan Publishers Limited.

Payne S.R.,University of Manchester | Payne S.R.,University of Warwick
Applied Acoustics | Year: 2013

This paper presents the development and testing of a Perceived Restorativeness Soundscape Scale (PRSS). The scale is designed to assess perceptions of a soundscape's potential to provide psychological restoration. In study one, 123 participants were presented with audio-visual recordings from a UK urban, urban park and rural environment, which they rated using the created PRSS. A series of factor analyses resulted in a two factor solution consisting of a General Factor and a Being-Away-To and Coherence Factor to represent PRSS results and its theoretical components. An urban soundscape was perceived as lower in restorative potential than an urban park soundscape, which was perceived as lower in restorative potential than the rural soundscape. In study two, 194 participants used the developed PRSS to rate the soundscape of a UK urban park they had just visited. Factor analyses resulted in a General one Factor solution. The PRSS was able to differentiate between soundscapes from different urban parks. The success of considering a positive benefit of soundscapes, psychological restoration, via the PRSS is discussed. © 2011 Elsevier Ltd. All rights reserved.

House T.,University of Warwick
Journal of the Royal Society Interface | Year: 2011

The last decade has seen much work on quantitative understanding of human behaviour, with online social interaction offering the possibility of more precise measurement of behavioural phenomena than was previously possible. A parsimonious model is proposed that incorporates several observed features of behavioural contagion not seen in existing epidemic model schemes, leading to metastable behavioural dynamics. © 2011 The Royal Society.

Dalgaard J.Z.,University of Warwick
Trends in Genetics | Year: 2012

Intuitively one would not expect that ribonucleotides are incorporated into nuclear DNA beyond their role in priming Okazaki fragments, nor that such incorporation would be functional. However, several recent studies have shown that not only are ribonucleotides present in the nuclear DNA, but that they can be incorporated by at least two different mechanisms: random 'mis'-incorporation of ribonucleotides, which occurs at a surprisingly high frequency; and site-specific incorporation at a stalled fork. Importantly, in the latter case, the ribonucleotides have been shown to have a biological function - acting to initiate a replication-coupled recombination event mediating a cell type change. Traditionally, it has been thought that 'random' ribonucleotide incorporation causes genetic instability, but new evidence suggests there may be a fine balance between mechanisms preventing and incorporating ribonucleotides into genomic DNA. Indeed, genomic ribonucleotides might have diverse roles affecting genetic stability, DNA damage repair, heterochromatin formation, cellular differentiation, and development. © 2012 Elsevier Ltd.

Winston A.P.,Eating Disorders Unit | Winston A.P.,University of Warwick
Annals of Clinical Biochemistry | Year: 2012

In anorexia nervosa, under-nutrition and weight regulatory behaviours such as vomiting and laxative abuse can lead to a range of biochemical problems. Hypokalaemia is the most common electrolyte abnormality. Metabolic alkalosis occurs in patients who vomit or abuse diuretics and acidosis in those misusing laxatives. Hyponatraemia is often due to excessive water ingestion, but may also occur in chronic energy deprivation or diuretic misuse. Urea and creatinine are generally low and normal concentrations may mask dehydration or renal dysfunction. Abnormalities of liver enzymes are predominantly characterized by elevation of aminotransferases, which may occur before or during refeeding. The serum albumin is usually normal, even in severely malnourished patients. Amenorrhoea is due to hypogonadotrophic hypogonadism. Reduced concentrations of free T4 and free T3 are frequently reported and T4 is preferentially converted to reverse T3. Cortisol is elevated but the response to adrenocorticotrophic hormone is normal. Hypoglycaemia is common. Hypercholesterolaemia is a common finding but its significance for cardiovascular risk is uncertain. A number of micronutrient deficiencies can occur. Other abnormalities include hyperamylasaemia, hypercarotenaemia and elevated creatine kinase. There is an increased prevalence of eating disorders in type 1 diabetes and the intentional omission of insulin is associated with impaired metabolic control. Refeeding may produce electrolyte abnormalities, hyper- and hypoglycaemia, acute thiamin depletion and fluid balance disturbance; careful biochemical monitoring and thiamin replacement are therefore essential during refeeding. Future research should address the management of electrolyte problems, the role of leptin and micronutrients, and the possible use of biochemical markers in risk stratification.

Monti S.,CNR Institute of Chemistry of organometallic Compounds | Walsh T.R.,University of Warwick
Journal of Physical Chemistry C | Year: 2011

The adsorption of the four DNA bases (adenine, guanine, thymine, and cytosine) on a mineral surface (titanium dioxide) is studied through classical molecular dynamics simulations and potential of mean constrained force calculations to give a reliable description of their binding behavior, identify the best binding arrangement, and quantify the strength of their interactions with the inorganic surface. Several configurations are identified, and the analysis of the data has revealed that the general tendency is to adsorb on structured solvent layers, which are in direct contact with the substrate. In this region, the molecules are perpendicular to the slab most of the time, do not adopt a preferential orientation, and explore different areas of the interposing water layers. Frequent escape into the bulk solvent is observed, suggesting that the interactions between the bases and the solvent layers are not strong enough to keep the molecule close to the surface. © 2011 American Chemical Society.

Petrenko O.A.,University of Warwick
Low Temperature Physics | Year: 2014

Recent progress in the understanding of the complex magnetic properties of the family of rare-earth strontium oxides, SrLn2O4, is reviewed. These compounds consisting of hexagons and triangles are affected by geometrical frustration and therefore exhibit its characteristic features, such as a significant reduction of magnetic ordering temperatures and complex phase diagrams in an applied field. Some of the observed features appear to be rather remarkable even in the context of the unusual behavior associated with geometrically frustrated magnetic systems. Of particular interest is the coexistence at the lowest temperature of different magnetic structures (exhibiting either long or short-range order) characterized by different propagation vectors in materials without significant chemical or structural disorder. © 2014 AIP Publishing LLC.

Gadsby R.,University of Warwick
Journal of Nutrition, Health and Aging | Year: 2013

Aim: To investigate the level of Percutaneous Endoscopic Gastrostomy (PEG) feeding in elderly people with diabetes resident in Nursing homes in one area of the UK, to describe their degree of disability, comorbidities and to estimate medication costs of these residents. Methods: The data was collected from a retrospective case notes review of the 75 people with known diabetes who were resident in the 11 Nursing homes in the Coventry Teaching PCT in early 2010. Results: 14 residents (19% of the total sample) had PEG feeds in situ and one (1.3%) had a nasogastric feeding tube in situ. The 14 residents were taking a total of 80 daily medications, a mean of 5.7 daily medications per resident (range 3-10). The total medication costs for the regular medications for these 14 residents was 2410 euros per month giving a mean of 172 euros/month (range 14-935 euros per month). All of the 14 were recorded as being bedbound, having no speech and being doubly incontinent. Conclusion: All 14 residents being PEG fed have severe levels of disability. Cerebro Vascular Accident and Dementia are the main recorded co-morbidities. The most expensive monthly medication costs were for special order liquid medications, many for cardio vascular disease prevention, which may be considered as inappropriate in such severely disabled residents. © 2013 Serdi and Springer Verlag France.

Nankivell P.C.,University of Warwick
Cochrane database of systematic reviews (Online) | Year: 2010

BACKGROUND: Tympanic membrane retractions are commonly managed by ENT surgeons. There is currently no consensus as to the indications, timing and options for management of this condition. OBJECTIVES: To study the effectiveness of different surgical options in the management of tympanic membrane retractions. SEARCH STRATEGY: We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2010 Issue 1); PubMed (1950 to 2010); EMBASE (1974 to 2010); CINAHL (1982 to 2010); BIOSIS Previews; ISI Web of Science; CAB Abstracts; LILACS; KoreaMed; IndMed; PakMediNet; China National Knowledge Infrastructure; ISCTRN; UKCRN; ICTRP and Google. The date of the search was 17 March 2010. SELECTION CRITERIA: Randomised controlled trials (RCTs) of the surgical management of tympanic membrane retraction pockets in adults or children. Staging of the retraction using a known system must have been performed. Studies of cholesteatoma or perforations were excluded. DATA COLLECTION AND ANALYSIS: Two authors independently collected and analysed data to minimise the effects of selection and reporting bias. MAIN RESULTS: Two RCTs were included, involving 71 participants. The first study showed no statistically significant benefit of cartilage graft tympanoplasty over a watch and wait policy for either disease progression or hearing outcome. The second showed no additional benefit from the insertion of ventilation tubes over cartilage tympanoplasty alone with regards to hearing outcome. AUTHORS' CONCLUSIONS: No evidence currently exists to either support or refute the role of surgery in the management of tympanic membrane retractions. Higher quality studies are much needed to ascertain this.

Thistlethwaite J.,University of Warwick | Moran M.,University of Queensland
Journal of Interprofessional Care | Year: 2010

As part of a World Health Organization (WHO) initiative we searched the literature to explore defined learning outcomes for interprofessional education between 1988, when the last WHO technical report on interprofessional education was published, and 2009. We describe and synthesize findings from 88 citations over this 21 year period. There is a variety in the way learning outcomes are presented but there are many similarities between specific outcomes and/or objectives. Papers describing educational interventions do not always include specific outcomes or objectives. Our findings have been integrated into a list of learning outcomes with six categories for further debate and discussion. This project is part of a wider initiative initiated by the WHO in 2007 to review the current position of interprofessional education worldwide. It is also a sub-project of a learning and teaching grant funded by the Carrick Institute for Learning and Teaching within Australia. In this paper we use the CAIPE definition of interprofessional education: "Occasions when two or more professions learn with, from and about each other to improve collaboration and the quality of care" (Barr, 2002). © 2010 Informa UK Ltd.

Hebenstreit D.,University of Warwick
Trends in Genetics | Year: 2013

Many genes produce mRNA irregularly, resulting in infrequent transcription bursts.Transcriptional bursting is a major source of noise, but its cause is unknown.Gene loops are a possible mechanism for generating bursts.Links between noise, transcription, looping, and polymerase pausing are examined. Expression levels of the same mRNA or protein vary significantly among the cells of an otherwise identical population. Such biological noise has great functional implications and is largely due to transcriptional bursting, the episodic production of mRNAs in short, intense bursts, interspersed by periods of transcriptional inactivity. Bursting has been demonstrated in a wide range of pro- and eukaryotic species, attesting to its universal importance. However, the mechanistic origins of bursting remain elusive. A different type of phenomenon, which has also been suggested to be widespread, is the physical interaction between the promoter and 3' end of a gene. Several functional roles have been proposed for such gene loops, including the facilitation of transcriptional reinitiation. Here, I discuss the most recent findings related to these subjects and argue that gene loops are a likely cause of transcriptional bursting and, thus, biological noise. © 2013 Elsevier Ltd.

Barber T.M.,University of Warwick | Franks S.,Imperial College London
Molecular and Cellular Endocrinology | Year: 2013

Polycystic Ovary Syndrome (PCOS) is a common endocrinopathy that is associated with an adverse metabolic profile including insulin resistance. There is a clear association between obesity, the development of PCOS and the severity of its phenotypic, biochemical and metabolic features. Evidence to support this link includes data from epidemiological, pathophysiological and genetic studies. Given the importance of obesity in the development and manifestation of PCOS, ongoing research into the many facets of adipocyte biology in women with the condition is important and should continue to be a priority. In this review article, we discuss the existing literature on fat distribution, adipokines, adipocyte hypertrophy and adipocyte steroid metabolism in women with PCOS. © 2012 Elsevier Ireland Ltd.

Apostolou M.,University of Warwick
Evolution and Human Behavior | Year: 2010

Evidence from the anthropological record indicates that in most human societies, parents control the mating access to their offspring. Based on these data, a model of sexual selection has been recently proposed, whereby along with female and male choice, parental choice constitutes a significant sexual selection force in our species. This model was found to provide a good account for the mating patterns which are typical of foraging societies. By employing data from the Standard Cross Cultural Sample, the present study aims at examining whether this model can also account for the mating patterns typical of agricultural and pastoral societies. In addition, comparisons between different society types are made and two model-derived hypotheses are tested. First, it is hypothesised that parents have more control over their offspring's mate choices in non-foraging societies. Second, it is hypothesised that male parents exert greater decision making power in agropastoral societies than in hunting and gathering ones. Both hypotheses are supported by the results presented here. The evolutionary implications of these findings are also explored. © 2010 Elsevier Inc. All rights reserved.

Green L.E.,University of Warwick
Small Ruminant Research | Year: 2010

We use epidemiology whenever we consider the management of sheep health. To measure a disease, we need a precise and unique case definition and we often use diagnostic tests to assist in defining a disease. Diagnostic tests are not always accurate. Thus, it is necessary to consider the decisions that will be taken, based on the result of testing, in order to decide the most useful approach to interpret a test based on its test sensitivity and specificity and the prevalence of the disease in a flock. This is particularly important when decisions on culling or selection of sheep to attain, e.g. freedom from disease, are made on the basis of test results. Infectious diseases spread within and between flocks in a variety of ways; brought-in sheep are the most likely source for introduction of a new pathogen or strain of a pathogen. When a pathogen enters a naïve flock, it spreads through susceptible sheep and persists in the flock, whilst there are susceptible sheep that can be infected. Pathogens use a variety of techniques to persist, including changes in the pathogen itself, alterations in infected hosts enabling them to remain infectious for prolonged periods or to be re-infected, persistence in other host species or in the environment. We need to consider these strategies to decide whether elimination or control of a particular pathogen is more likely to be effective. Whatever the flock control strategy, treatment of diseased individuals is essential for their welfare and can also protect the rest of the flock, if treatment reduces the infectious period. Decisions on management of disease are based on our knowledge of the flock and its management and the evidence base for various control strategies. There are now formal techniques for evaluating the evidence base that can assist in evaluating evidence. One area where we need to evaluate evidence is on cause. It is not possible to prove anything, but we can use the weight of evidence to evaluate likely cause. There are nine aspects of association with which we can evaluate a piece of evidence; these are: strength, consistency, specificity, temporality, dose-response, plausibility, coherence, experiment and analogy. © 2010 Elsevier B.V.

Atkinson N.J.,Roslin Institute | Witteveldt J.,Roslin Institute | Evans D.J.,University of Warwick | Simmonds P.,Roslin Institute
Nucleic Acids Research | Year: 2014

Most RNA viruses infecting mammals and other vertebrates show profound suppression of CpG and UpA dinucleotide frequencies. To investigate this functionally, mutants of the picornavirus, echovirus 7 (E7), were constructed with altered CpG and UpA compositions in two 1.1-1.3 Kbase regions. Those with increased frequencies of CpG and UpA showed impaired replication kinetics and higher RNA/infectivity ratios compared with wild-type virus. Remarkably, mutants with CpGs and UpAs removed showed enhanced replication, larger plaques and rapidly outcompeted wild-type virus on co-infections. Luciferase-expressing E7 sub-genomic replicons with CpGs and UpAs removed from the reporter gene showed 100-fold greater luminescence. E7 and mutants were equivalently sensitive to exogenously added interferon-β, showed no evidence for differential recognition by ADAR1 or pattern recognition receptors RIG-I, MDA5 or PKR. However, kinase inhibitors roscovitine and C16 partially or entirely reversed the attenuated phenotype of high CpG and UpA mutants, potentially through inhibition of currently uncharacterized pattern recognition receptors that respond to RNA composition. Generating viruses with enhanced replication kinetics has applications in vaccine production and reporter gene construction. More fundamentally, the findings introduce a new evolutionary paradigm where dinucleotide composition of viral genomes is subjected to selection pressures independently of coding capacity and profoundly influences host-pathogen interactions. © 2014 The Author(s). Published by Oxford University Press.

L'vov V.S.,Weizmann Institute of Science | Nazarenko S.V.,University of Warwick
Physical Review B - Condensed Matter and Materials Physics | Year: 2012

We comment on the paper by Sonin with most statements of which we disagree. We use this option to shed light on some important issues of a theory of Kelvin-wave turbulence, touched on in Sonin's paper, in particular, on the relation between the Vinen spectrum of strong and the L'vov-Nazarenko spectrum of weak turbulence of Kelvin waves. We also discuss the role of explicit calculation of the Kelvin-wave interaction Hamiltonian and "symmetry arguments" that have to resolve a contradiction between the Kozik-Svistunov and the L'vov-Nazarenko spectrum of weak turbulence of Kelvin waves. © 2012 American Physical Society.

Lucas E.,University of Warwick
Reproductive BioMedicine Online | Year: 2013

The early embryonic environment has been shown to be remarkably influential on the developing organism, despite the relative brevity of this developmental stage. The cells of the zygote and cleavage-stage embryo hold the potential to form all cell lineages of the embryonic and extra-embryonic tissues, with gradual fate restriction occurring from the time of compaction and blastocyst formation. As such, these cells carry with them the potential to influence the phenotype of all successive cell types as the organism grows, differentiates and ages. The implication is, therefore, that sublethal adverse conditions which alter the developmental trajectory of these cells may have long-term implications for the health and development of the resulting offspring. One confirmed mechanism for the translation of environmental cues to phenotypic outcome is epigenetic modification of the genome to modulate chromatin packaging and gene expression in a cell- and lineage-specific manner. The influence of the periconceptional milieu on the epigenetic profile of the developing embryo has become a popular research focus in the quest to understand the effects of environment, nutrition and assisted reproduction technology on human development and health. © 2013, Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Background: The Objective Structured Clinical Examination (OSCE), originally developed in the 1970's, has been hailed as the "gold standard" of clinical assessments for medical students and is used within medical schools throughout the world. The Clinical assessment of Skills and Competencies (CASC) is an OSCE used as a clinical examination gateway, granting access to becoming a senior Psychiatrist in the UK.Discussion: Van der Vleuten's utility model is used to examine the CASC from the viewpoint of a senior psychiatrist. Reliability may be equivalent to more traditional examinations. Whilst the CASC is likely to have content validity, other forms of validity are untested and authenticity is poor. Educational impact has the potential to change facets of psychiatric professionalism and influence future patient care. There are doubts about acceptability from candidates and more senior psychiatrists.Summary: Whilst OSCEs may be the best choice for medical student examinations, their use in post graduate psychiatric examination in the UK is subject to challenge on the grounds of validity, authenticity and educational impact. © 2011 Marwaha; licensee BioMed Central Ltd.

Nautiyal J.,Imperial College London | Christian M.,University of Warwick | Parker M.G.,Imperial College London
Trends in Endocrinology and Metabolism | Year: 2013

Nuclear receptors (NRs) regulate tissue development and function by controlling transcription from distinct sets of genes in response to fluctuating levels of hormones or cues that modulate receptor activity. Such target gene activation or repression depends on the recruitment of coactivators or corepressors that lead to chromatin remodelling in the vicinity of target genes. Similarly to receptors, coactivators and corepressors often serve pleiotropic functions, and Nrip1 (RIP140) is no exception, playing roles in animal development and physiology. At first sight, however, RIP140 is unusual in its ability to function either as a coactivator or as a corepressor, and also serve a cytoplasmic role. The functions of RIP140 in different tissues will be summarised together with its potential contribution to disease. © 2013 Elsevier Ltd.

Maropoulos P.G.,University of Bath | Ceglarek D.,University of Warwick
CIRP Annals - Manufacturing Technology | Year: 2010

The verification and validation of engineering designs are of primary importance as they directly influence production performance and ultimately define product functionality and customer perception. Research in aspects of verification and validation is widely spread ranging from tools employed during the digital design phase, to methods deployed for prototype verification and validation. This paper reviews the standard definitions of verification and validation in the context of engineering design and progresses to provide a coherent analysis and classification of these activities from preliminary design, to design in the digital domain and the physical verification and validation of products and processes. The scope of the paper includes aspects of system design and demonstrates how complex products are validated in the context of their lifecycle. Industrial requirements are highlighted and research trends and priorities identified. © 2010 CIRP.

Soyer O.S.,University of Warwick | O'Malley M.A.,University of Sydney
BioEssays | Year: 2013

Evolutionary systems biology (ESB) is a rapidly growing integrative approach that has the core aim of generating mechanistic and evolutionary understanding of genotype-phenotype relationships at multiple levels. ESB's more specific objectives include extending knowledge gained from model organisms to non-model organisms, predicting the effects of mutations, and defining the core network structures and dynamics that have evolved to cause particular intracellular and intercellular responses. By combining mathematical, molecular, and cellular approaches to evolution, ESB adds new insights and methods to the modern evolutionary synthesis, and offers ways in which to enhance its explanatory and predictive capacities. This combination of prediction and explanation marks ESB out as a research manifesto that goes further than its two contributing fields. Here, we summarize ESB via an analysis of characteristic research examples and exploratory questions, while also making a case for why these integrative efforts are worth pursuing. © 2013 WILEY Periodicals, Inc.

Rayman M.P.,University of Surrey | Stranges S.,University of Warwick
Free Radical Biology and Medicine | Year: 2013

The potential of some selenoproteins to protect against oxidative stress led to the expectation that selenium would be protective against type 2 diabetes, and indeed in early in vivo and in vitro studies, selenium (as selenate) was shown to have antidiabetic and insulin-mimetic effects. However, more recently, findings from observational cross-sectional studies have raised concern that high selenium exposure may be associated with type 2 diabetes or insulin resistance, at least in well-nourished populations, though trial results have been inconsistent. Moreover, the largest trials that investigated the effects of selenium supplementation on diabetes endpoints have had cancer prevention as their primary outcome, casting doubt on the interpretation of posthoc analyses. Factors affecting serum/plasma selenium are not just location and level of disease-associated inflammation but the fact that higher concentrations of plasma selenoprotein P yet lower concentrations of glutathione peroxidase are found in type 2 diabetic patients than in normal subjects. From a public health perspective, selenium is marketed as a dietary supplement and is commonly added to multivitamin/mineral preparations that are consumed in many Western countries. Based on current evidence, however, the indiscriminate use of selenium supplements in individuals and populations with adequate-to-high selenium status cannot be justified and may increase risk. In conclusion, although there is a clear link between certain selenoproteins and glucose metabolism or insulin resistance, the relationship between selenium and type 2 diabetes is undoubtedly complex. It is possible that the relationship is U-shaped, with possible harm occurring both below and above the physiological range for optimal activity of some or all selenoproteins. © 2013 Elsevier Inc.

Becraft P.W.,Iowa State University | Gutierrez-Marcos J.,University of Warwick
Wiley Interdisciplinary Reviews: Developmental Biology | Year: 2012

The endosperm is a product of fertilization that evolved to support and nourish its genetic twin sibling embryo. Cereal endosperm accumulates starch and protein stores, which later support the germinating seedling. These nutritional stores prompted the domestication of cereals and are the focus of ongoing efforts for crop improvement and biotechnological innovations. Endosperm development entails several novel modifications to basic cellular and developmental processes. Cereals display nuclear endosperm development, which begins with a period of free nuclear division to generate a coenocyte. Cytoskeletal arrays distribute nuclei around the periphery of the cytoplasm and direct the subsequent deposition of cell wall material during cellularization. Positional cues and signaling systems function dynamically in the specification of the four major cell types: transfer cells, embryo-surrounding cells, starchy endosperm (SE), and aleurone. Genome balance, epigenetic gene regulation, and parent-of-origin effects are essential for directing these processes. Transfer cells transport solutes, including sugars and amino acids, from the maternal plant tissues into the developing grain where they are partitioned between embryo and SE cells. Cells of the embryo-surrounding region appear to coordinate development of the embryo and endosperm. As the seed matures, SE cells assimilate starch and protein stores, undergo DNA endoreduplication, and finally undergo programmed cell death. In contrast, aleurone cells follow a maturation program similar to the embryo, allowing them to survive desiccation. At germination, the aleurone cells secrete amylases and proteases that hydrolyze the storage products of the SE to nourish the germinating seedling. © 2012 Wiley Periodicals, Inc.

Dehnen-Schmutz K.,University of Warwick
Journal of Applied Ecology | Year: 2011

1. Ornamental horticulture is the most important pathway for plant invasions world-wide. Large numbers of non-native plants are used as ornamentals, and current policies fail to effectively address the continued escape of species from cultivation. Legislative measures are often limited to the listing of few high-risk species banned from sale or planting. This approach, however, may give the impression that non-listed species are not considered to be a risk and are therefore safe to use. The continued widespread use of species not yet identified as having the risk to become invasive may create a problem in the future. 2. This article argues that knowledge gained from studies designed to identify invasive traits of species and factors contributing to their invasion success can also be used to identify species with a low invasion risk that can be recommended to the horticultural trade, landscaping sector and gardeners for safer use. 3. The criteria identified for non-invading species to be listed in a green list include sufficiently long residence time, high propagule pressure, no records of invasive occurrences elsewhere and an indication of some robustness to climate change. An example is provided for a random sample of ornamental species used in Britain. 4. Synthesis and application. There is a pressing need to prevent further plant invasions resulting from ornamental horticulture. A green list of non-native ornamental species that have been assessed as having a low risk of escaping cultivation will contribute to the prevention of plant invasions. Species not yet assessed which may have the potential to become invasive in the future can then be more easily avoided. This list would be particularly useful in large-scale plantings and landscaping projects. Currently, policies often focus on (i) species that are already introduced and recognized as invasive and (ii) the prevention of potential further invasions from new introductions. This study suggests that attention to non-invasive species already present in the country and widely used in horticulture can help to advance policies for dealing with invasive ornamental species. © 2011 The Author. Journal of Applied Ecology © 2011 British Ecological Society.

Rangnekar D.,University of Warwick
Environment and Planning A | Year: 2011

A range of social movements mobilise around and seek to valorise 'place-based' imageries. There is, these movements argue, vitality in place. As anthropologists remind us, people continue to construct some form of boundaries around place, however permeable and transient those boundaries might be. In the context of global agrifood, a diversity of socially generated marks indicating conditions of origin have emerged that seek to speak to a range of moral economies. Within this constellation, Geographical Indication (GI) appears as a remarkable place-based intellectual property which the author appreciates as the juridical reification of a place-based stabilisation of cultural norms. However, rather than idealise GIs, the paper also probes a 'politics in place' through a fieldwork-based study of a recently acquired GI for Feni, a liquor distilled from either coconut or cashew apples. Juxtaposing observations of Feni distilling with the specifications that constitute the GI, the paper explains these differences in terms of the local social relations of power. The Goa government aligned itself with the recently established Feni Association, composed mainly of large distillers with bottling operations, to acquire the GI and was successful because of the complicity of the GI Registry office. © 2011 Pion Ltd and its Licensors.

Rees K.,University of Warwick
The Cochrane database of systematic reviews | Year: 2013

The Seven Countries study in the 1960s showed that populations in the Mediterranean region experienced lower cardiovascular disease (CVD) mortality probably as a result of different dietary patterns. Later observational studies have confirmed the benefits of adherence to a Mediterranean dietary pattern on CVD risk factors. Clinical trial evidence is limited, and is mostly in secondary prevention. To determine the effectiveness of a Mediterranean dietary pattern for the primary prevention of CVD. We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL, Issue 9 of 12, September 2012); MEDLINE (Ovid, 1946 to October week 1 2012); EMBASE (Ovid, 1980 to 2012 week 41); ISI Web of Science (1970 to 16 October 2012); Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment Database and Health Economics Evaluations Database (Issue 3 of 12, September 2012). We searched trial registers and reference lists of reviews and applied no language restrictions. We selected randomised controlled trials in healthy adults and adults at high risk of CVD. A Mediterranean dietary pattern was defined as comprising at least two of the following components: (1) high monounsaturated/saturated fat ratio, (2) low to moderate red wine consumption, (3) high consumption of legumes, (4) high consumption of grains and cereals, (5) high consumption of fruits and vegetables, (6) low consumption of meat and meat products and increased consumption of fish, and (7) moderate consumption of milk and dairy products. The comparison group received either no intervention or minimal intervention. Outcomes included clinical events and CVD risk factors. Two review authors independently extracted data and contacted chief investigators to request additional relevant information. We included 11 trials (15 papers) (52,044 participants randomised). Trials were heterogeneous in the participants recruited, in the number of dietary components and follow-up periods. Seven trials described the intervention as a Mediterranean diet. Clinical events were reported in only one trial (Women's Health Initiative 48,835 postmenopausal women, intervention not described as a Mediterranean diet but increased fruit and vegetable and cereal intake) where no statistically significant effects of the intervention were seen on fatal and non-fatal endpoints at eight years. Small reductions in total cholesterol (-0.16 mmol/L, 95% confidence interval (CI) -0.26 to -0.06; random-effects model) and low-density lipoprotein (LDL) cholesterol (-0.07 mmol/L, 95% CI -0.13 to -0.01) were seen with the intervention. Subgroup analyses revealed statistically significant greater reductions in total cholesterol in those trials describing the intervention as a Mediterranean diet (-0.23 mmol/L, 95% CI -0.27 to -0.2) compared with control (-0.06 mmol/L, 95% CI -0.13 to 0.01). Heterogeneity precluded meta-analyses for other outcomes. Reductions in blood pressure were seen in three of five trials reporting this outcome. None of the trials reported adverse events. The limited evidence to date suggests some favourable effects on cardiovascular risk factors. More comprehensive interventions describing themselves as the Mediterranean diet may produce more beneficial effects on lipid levels than those interventions with fewer dietary components. More trials are needed to examine the impact of heterogeneity of both participants and the intervention on outcomes.

Hartley L.,University of Warwick
The Cochrane database of systematic reviews | Year: 2013

There is increasing evidence that both green and black tea are beneficial for cardiovascular disease (CVD) prevention. To determine the effects of green and black tea on the primary prevention of CVD. We searched the following databases on 12 October 2012 without language restrictions: CENTRAL in The Cochrane Library, MEDLINE (OVID), EMBASE (OVID) and Web of Science (Thomson Reuters). We also searched trial registers, screened reference lists and contacted authors for additional information where necessary. Randomised controlled trials (RCTs) lasting at least three months involving healthy adults or those at high risk of CVD. Trials investigated the intake of green tea, black tea or tea extracts. The comparison group was no intervention, placebo or minimal intervention. The outcomes of interest were CVD clinical events and major CVD risk factors. Any trials involving multifactorial lifestyle interventions or focusing on weight loss were excluded to avoid confounding. Two review authors independently selected trials for inclusion, abstracted data and assessed the risk of bias. Trials of green tea were analysed separately from trials of black tea. We identified 11 RCTs with a total of 821 participants, two trials awaiting classification and one ongoing trial. Seven trials examined a green tea intervention and four examined a black tea intervention. Dosage and form of both green and black tea differed between trials. The ongoing trial is examining the effects of green tea powder capsules.No studies reported cardiovascular events.Black tea was found to produce statistically significant reductions in low-density lipoprotein (LDL) cholesterol (mean difference (MD) -0.43 mmol/L, 95% confidence interval (CI) -0.56 to -0.31) and blood pressure (systolic blood pressure (SBP): MD -1.85 mmHg, 95% CI -3.21 to -0.48. Diastolic blood pressure (DBP): MD -1.27 mmHg, 95% CI -3.06 to 0.53) over six months, stable to sensitivity analysis, but only a small number of trials contributed to each analysis and studies were at risk of bias.Green tea was also found to produce statistically significant reductions in total cholesterol (MD -0.62 mmol/L, 95% CI -0.77 to -0.46), LDL cholesterol (MD -0.64 mmol/L, 95% CI -0.77 to -0.52) and blood pressure (SBP: MD -3.18 mmHg, 95% CI -5.25 to -1.11; DBP: MD -3.42, 95% CI -4.54 to -2.30), but only a small number of studies contributed to each analysis, and results were not stable to sensitivity analysis. When both tea types were analysed together they showed favourable effects on LDL cholesterol (MD -0.48 mmol/L, 95% CI -0.61 to -0.35) and blood pressure (SBP: MD -2.25 mmHg, 95% CI -3.39 to -1.11; DBP: MD -2.81 mmHg, 95% CI -3.77 to -1.86). Adverse events were measured in five trials and included a diagnosis of prostate cancer, hospitalisation for influenza, appendicitis and retinal detachment but these are unlikely to be directly attributable to the intervention. There are very few long-term studies to date examining green or black tea for the primary prevention of CVD. The limited evidence suggests that tea has favourable effects on CVD risk factors, but due to the small number of trials contributing to each analysis the results should be treated with some caution and further high quality trials with longer-term follow-up are needed to confirm this.

Rees K.,University of Warwick
The Cochrane database of systematic reviews | Year: 2013

Changes in population diet are likely to reduce cardiovascular disease and cancer, but the effect of dietary advice is uncertain. This review is an update of a previous review published in 2007. To assess the effects of providing dietary advice to achieve sustained dietary changes or improved cardiovascular risk profile among healthy adults. We searched the Cochrane Central Register of Controlled Trials, the Database of Abstracts of Reviews of Effects (DARE) and the HTA database on The Cochrane Library (Issue 4, 2010). We searched MEDLINE (Ovid) (1950 to week 2 October 2010) and EMBASE (Ovid) (1980 to Week 42 2010). Additional searches were done on CAB Health (1972 to December 1999), CVRCT registry (2000), CCT (2000) and SIGLE (1980 to 2000). Dissertation abstracts and reference lists of articles were checked and researchers were contacted. Randomised studies with no more than 20% loss to follow-up, lasting at least three months and involving healthy adults comparing dietary advice with no advice or minimal advice. Trials involving children, trials to reduce weight or those involving supplementation were excluded. Two review authors independently assessed trial quality and extracted data. Study authors were contacted for additional information. Forty-four trials with 52 intervention arms (comparisons) comparing dietary advice with no advice were included in the review; 18,175 participants or clusters were randomised. Twenty-nine of the 44 included trials were conducted in the USA. Dietary advice reduced total serum cholesterol by 0.15 mmol/L (95% CI 0.06 to 0.23) and LDL cholesterol by 0.16 mmol/L (95% CI 0.08 to 0.24) after 3 to 24 months. Mean HDL cholesterol levels and triglyceride levels were unchanged. Dietary advice reduced blood pressure by 2.61 mm Hg systolic (95% CI 1.31 to 3.91) and 1.45 mm Hg diastolic (95% CI 0.68 to 2.22) and 24-hour urinary sodium excretion by 40.9 mmol (95% CI 25.3 to 56.5) after 3 to 36 months but there was heterogeneity between trials for the latter outcome. Three trials reported plasma antioxidants, where small increases were seen in lutein and β-cryptoxanthin, but there was heterogeneity in the trial effects. Self-reported dietary intake may be subject to reporting bias, and there was significant heterogeneity in all the following analyses. Compared to no advice, dietary advice increased fruit and vegetable intake by 1.18 servings/day (95% CI 0.65 to 1.71). Dietary fibre intake increased with advice by 6.5 g/day (95% CI 2.2 to 10.82), while total dietary fat as a percentage of total energy intake fell by 4.48% (95% CI 2.47 to 6.48) with dietary advice, and saturated fat intake fell by 2.39% (95% CI 1.4 to 3.37).Two trials analysed incident cardiovascular disease (CVD) events (TOHP I/II). Follow-up was 77% complete at 10 to 15 years after the end of the intervention period and estimates of event rates lacked precision but suggested that sodium restriction advice probably led to a reduction in cardiovascular events (combined fatal plus non-fatal events) plus revascularisation (TOHP I hazards ratio (HR) 0.59, 95% CI 0.33 to 1.08; TOHP II HR 0.81, 95% CI 0.59 to 1.12). Dietary advice appears to be effective in bringing about modest beneficial changes in diet and cardiovascular risk factors over approximately 12 months, but longer-term effects are not known.

Angel K.,University of Warwick
Current Opinion in Psychiatry | Year: 2010

Purpose of Review: To provide an overview of conceptualizations of female sexual problems, and 'Female Sexual Dysfunction' in particular, throughout the 20th century, especially in relation to psychiatry and mental illness. Recent Findings: In the past 15 years, there has been an increase in both medical and public discourse about 'Female Sexual Dysfunction'. I discuss a variety of literature sources dealing with female sexual problems, where these are understood variously as problems of developmental psychopathology, as technical phenomena to be resolved through education, or as medical problems to be addressed pharmaceutically. Summary: The stigma of mental illness shapes much recent discussion of female sexual problems, as does the legacy of the postwar critique of psychodynamic psychiatry. © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Hartley L.,University of Warwick
The Cochrane database of systematic reviews | Year: 2013

There is increasing evidence that high consumption of fruit and vegetables is beneficial for cardiovascular disease (CVD) prevention. The primary objective is to determine the effectiveness of i) advice to increase fruit and vegetable consumption ii) the provision of fruit and vegetables to increase consumption, for the primary prevention of CVD.  We searched the following electronic databases: The Cochrane Library (2012, issue 9-CENTRAL, HTA, DARE, NEED), MEDLINE (1946 to week 3 September 2012); EMBASE (1980 to 2012 week 39) and the Conference Proceedings Citation Index - Science on ISI Web of Science (5 October 2012). We searched trial registers, screened reference lists and contacted authors for additional information where necessary. No language restrictions were applied. Randomised controlled trials with at least three months follow-up (follow-up was considered to be the time elapsed since the start of the intervention) involving healthy adults or those at high risk of CVD. Trials investigated either advice to increase fruit and vegetable intake (via any source or modality) or the provision of fruit and vegetables to increase intake. The comparison group was no intervention or minimal intervention. Outcomes of interest were CVD clinical events (mortality (CVD and all-cause), myocardial infarction (MI), coronary artery bypass grafting (CABG) or percutaneous transluminal coronary angioplasty (PTCA), angiographically-defined angina pectoris, stroke, carotid endarterectomy, peripheral arterial disease (PAD)) and major CVD risk factors (blood pressure, blood lipids, type 2 diabetes). Trials involving multifactorial lifestyle interventions (including different dietary patterns, exercise) or where the focus was weight loss were excluded to avoid confounding. Two review authors independently selected trials for inclusion, extracted data and assessed the risk of bias. Trials of provision of fruit and vegetables were analysed separately from trials of dietary advice. We identified 10 trials with a total of 1730 participants randomised, and one ongoing trial. Six trials investigated the provision of fruit and vegetables, and four trials examined advice to increase fruit and vegetable consumption.The ongoing trial is examining the provision of an avocado-rich diet.The number and type of intervention components for provision, and the dietary advice provided differed between trials.None of the trials reported clinical events as they were all relatively short term. There was no strong evidence for effects of individual trials of provision of fruit and vegetables on cardiovascular risk factors, but trials were heterogeneous and short term. Furthermore, five of the six trials only provided one fruit or vegetable. Dietary advice showed some favourable effects on blood pressure (systolic blood pressure (SBP): mean difference (MD) -3.0 mmHg (95% confidence interval (CI) -4.92 to -1.09), diastolic blood pressure (DBP): MD -0.90 mmHg (95% CI -2.03 to 0.24)) and low-density lipoprotein (LDL) cholesterol but analyses were based on only two trials. Three of the 10 included trials examined adverse effects, which included increased bowel movements, bad breath and body odour. There are very few studies to date examining provision of, or advice to increase the consumption of, fruit and vegetables in the absence of additional dietary interventions or other lifestyle interventions for the primary prevention of CVD. The limited evidence suggests advice to increase fruit and vegetables as a single intervention has favourable effects on CVD risk factors but more trials are needed to confirm this.

Rees K.,University of Warwick
Cochrane database of systematic reviews (Online) | Year: 2013

Selenium is a key component of a number of selenoproteins which protect against oxidative stress and have the potential to prevent chronic diseases including cardiovascular disease (CVD). However, observational studies have shown inconsistent associations between selenium intake and CVD risk; in addition, there is concern around a possible increased risk of type 2 diabetes with high selenium exposure. To determine the effectiveness of selenium only supplementation for the primary prevention of CVD and examine the potential adverse effect of type 2 diabetes. The following electronic databases were searched: the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 10 of 12, October 2012) on The Cochrane Library; MEDLINE (Ovid) (1946 to week 2 October 2012); EMBASE Classic + EMBASE (Ovid) (1947 to 2012 Week 42); CINAHL (EBSCO) (to 24 October 2012); ISI Web of Science (1970 to 24 October 2012); PsycINFO (Ovid) (1806 to week 3 October 2012); Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment Database and Health Economics Evaluations Database (Issue 4 of 4, October 2012) on The Cochrane Library. Trial registers and reference lists of reviews and articles were searched and experts in the field were approached. No language restrictions were applied. Randomised controlled trials on the effects of selenium only supplementation on major CVD end-points, mortality, changes in CVD risk factors, and type 2 diabetes were included both in adults of all ages from the general population and in those at high risk of CVD. Trials were only considered where the comparison group was placebo or no intervention. Only studies with at least three months follow-up were included in the meta-analyses, shorter term studies were dealt with descriptively. Two review authors independently assessed trial quality and extracted data. Study authors were contacted for additional information. Twelve trials (seven with duration of at least three months) met the inclusion criteria, with 19,715 participants randomised. The two largest trials that were conducted in the USA (SELECT and NPC) reported clinical events. There were no statistically significant effects of selenium supplementation on all cause mortality (RR 0.97, 95% CI 0.88 to 1.08), CVD mortality (RR 0.97, 95% CI 0.79 to 1.2), non-fatal CVD events (RR 0.96, 95% CI 0.89 to 1.04) or all CVD events (fatal and non-fatal) (RR 1.03, 95% CI 0.95 to 1.11). There was a small increased risk of type 2 diabetes with selenium supplementation but this did not reach statistical significance (RR 1.06, 95% CI 0.97 to 1.15). Other adverse effects that increased with selenium supplementation, as reported in the SELECT trial, included alopecia (RR 1.28, 95% CI 1.01 to 1.62) and dermatitis grade 1 to 2 (RR 1.17, 95% CI 1.0 to 1.35). Selenium supplementation reduced total cholesterol but this did not reach statistical significance (WMD - 0.11 mmol/L, 95% CI - 0.3 to 0.07). Mean high density lipoprotein (HDL) levels were unchanged. There was a statistically significant reduction in non-HDL cholesterol (WMD - 0.2 mmol/L, 95% CI - 0.41 to 0.00) in one trial of varying selenium dosage. None of the longer term trials examined effects on blood pressure. Overall, the included studies were regarded as at low risk of bias. The limited trial evidence that is available to date does not support the use of selenium supplements in the primary prevention of CVD.

Martin T.A.D.,University of Warwick
International Journal of Modern Physics A | Year: 2015

A brief summary is reported on measurements of soft and hard diffractive processes by the ATLAS, CMS and TOTEM collaborations at a center of mass energy of 7 TeV. © 2015 World Scientific Publishing Company.

Veras D.,University of Warwick
Celestial Mechanics and Dynamical Astronomy | Year: 2014

Planetary, stellar and galactic physics often rely on the general restricted gravitational N-body problem to model the motion of a small-mass object under the influence of much more massive objects. Here, I formulate the general restricted problem entirely and specifically in terms of the commonly used orbital elements of semimajor axis, eccentricity, inclination, longitude of ascending node, argument of pericentre, and true anomaly, without any assumptions about their magnitudes. I derive the equations of motion in the general, unaveraged case, as well as specific cases, with respect to both a bodycentric and barycentric origin. I then reduce the equations to three-body systems, and present compact singly- and doubly-averaged expressions which can be readily applied to systems of interest. This method recovers classic Lidov-Kozai and Laplace-Lagrange theory in the test particle limit to any order, but with fewer assumptions, and reveals a complete analytic solution for the averaged planetary pericentre precession in coplanar circular circumbinary systems to at least the first three nonzero orders in semimajor axis ratio. Finally, I show how the unaveraged equations may be used to express resonant angle evolution in an explicit manner that is not subject to expansions of eccentricity and inclination about small nor any other values. © 2014 Springer Science+Business Media Dordrecht.

Roberts J.,University of Warwick
Sociology of Health and Illness | Year: 2012

Commercial companies market 4D ultrasound scans to expectant parents for the stated purpose of reassurance, to promote bonding, and to get 'baby's first picture'. This article describes in detail the process of commercial 4D scanning in the UK, paying particular attention to the discursive exchanges in the scan room. It is argued that sonographers and clients engage in a process of 'collaborative coding' that, despite the realism of 4D, is essential to making the imagery on the screen personally and socially meaningful. While sonographers first help clients to get their bearings, expectant parents and others often engage in a complex process of narrating the images on the screen as they are created. The capacities of 4D ultrasound to image facial features and movements inform stories about fetal experience and family resemblances as well as enabling playfully imagined interactions with the fetus. While these stories are primarily based in experiences of the visual, there is also evidence that pregnant women seek to map the image onto their bodies and to reintroduce some elements of their embodied experiences into the narratives. © 2011 The Author. Sociology of Health & Illness © 2011 Foundation for the Sociology of Health & Illness/Blackwell Publishing Ltd.

Kerr R.M.,University of Warwick
Physical Review Letters | Year: 2011

A pair of perturbed antiparallel quantum vortices, simulated using the three-dimensional Gross-Pitaevskii equations, is shown to be unstable to vortex stretching. This results in kinetic energy K â̂‡ψ being converted into interaction energy E I and eventually local kinetic energy depletion that is similar to energy decay in a classical fluid, even though the governing equations are Hamiltonian and energy conserving. The intermediate stages include the generation of vortex waves, their deepening, multiple reconnections, the emission of vortex rings and phonons, and the creation of an approximately -5/3 kinetic energy spectrum at high wave numbers. All of the wave generation and reconnection steps follow from interactions between the two original vortices. A four vortex example is given to demonstrate that some of these steps might be general. © 2011 American Physical Society.

Coja-Oghlan A.,University of Warwick
SIAM Journal on Computing | Year: 2010

Let Φ be a uniformly distributed random k-SAT formula with n variables and m clauses. We present a polynomial time algorithm that finds a satisfying assignment of Φ with high probability for constraint densities m/n < (1 - εk)2k In(k)/k, where εk → 0. Previously no efficient algorithm was known to find satisfying assignments with a nonvanishing probability beyond m/n = 1.817 · 2k/k [A. Frieze and S. Suen, J. Algorithms, 20 (1996), pp. 312-355]. © 2010 Society for Industrial and Applied Mathematics.

Gates S.,University of Warwick
The Cochrane database of systematic reviews | Year: 2013

Subcutaneous and sub rectus sheath wound drains are sometimes used in women who have undergone caesarean section. The indications for using drains vary by clinician. To compare the effects of using a wound drain with not using a wound drain at caesarean section, and of different types of drain, on maternal health and healthcare resource use. In November 2013, for this second update, we searched the Cochrane Wounds Group Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); Ovid Medline; Ovid Medline - In-Process & Other Non-Indexed Citations; Ovid Embase; and EBSCO CINAHL. No date, language or publication status limits were applied Studies were included if they allocated women to groups at random and they compared any type of wound drain with no wound drainage, or with any other type of drain, in women undergoing caesarean section. Trials were evaluated for appropriateness for inclusion and methodological quality without consideration of their results. This was done by two reviewers according to pre-stated eligibility criteria. Ten trials that recruited 5248 women were included in the review. Meta-analysis found no evidence of a difference in the risk of wound infection, other wound complications, febrile morbidity or pain in women who had wound drains compared with those who did not. There was some evidence from one trial that a subcutaneous drain may increase wound infection compared to a sub-sheath drain (RR 5.42, 95% CI 1.28 to 22.98). No differences in outcomes were found between subcutaneous drainage and subcutaneous suturing in the three trials that made this comparison. Existing evidence suggests that the routine use of wound drains at caesarean section does not confer any substantial benefit to the women involved. However, neither moderate benefit nor harm are excluded.

Martini P.,University of Warwick
Vision Research | Year: 2010

Inter-trial repetitions of a target's features in a visual search task reduce the time needed to find the target. Here I examine these sequential dependencies in the Priming of Pop-Out task (PoP) by means of system identification techniques. The results are as follows. Response time facilitation due to repetition of the target's features increases linearly with difficulty in segmenting the target from the distracters. However, z-scoring the reaction times normalizes responses by equating facilitation across levels of difficulty. Memory kernels, representing the influence of the current trial on any future trial, can then be calculated from data normalized and averaged across conditions and observers. The average target-defining feature kernel and the target position kernel are well fit by a sum of two exponentials model, comprised of a high-gain, fast-decay component and a low-gain, slow-decay component. In contrast, the average response-defining feature kernel is well fit by a single exponential model with very low-gain and decay similar to the slow component of the target-defining feature kernel. Analysis of single participant's data reveals that a fast-decay component is often also present for the response-defining feature, but can be either facilitatory or inhibitory and thus tends to cancel out in pooled data. Overall, the results are similar to integration functions of reward history recently observed in primates during frequency-matching experiments. I speculate that sequential dependencies in PoP result from learning mechanisms that bias the attentional weighting of certain aspects of the stimulus in an effort to minimize a prediction error signal. © 2010 Elsevier Ltd.

In this note, I address the use of improper priors on the shape parameters of some asymmetric exponential power models. It is shown that the use of certain prior structures, with improper priors on the shape parameters, lead to improper posteriors. These results imply that the posteriors associated to some of the asymmetric exponential power models studied in Naranjo et al. (2014) are improper. Alternative improper priors, inspired by the structure of the independence Jeffreys prior, as well as vague proper priors are pointed out. © 2014 Springer Science+Business Media New York.

Crawford G.S.,University of Warwick
International Journal of Industrial Organization | Year: 2012

Empirical models of differentiated product demand are widely used by both academics and practitioners. While these methods treat carefully the potential endogeneity of price, until recently they have assumed the number and characteristics of the products offered by firms are exogenous. This paper presents a progress report on an ongoing research agenda to address this issue. First, it summarizes how the appropriate choice of "orthogonal" instruments can yield consistent estimates of own and cross-price elasticities in the presence of endogenous product characteristics. Second, it summarizes how to measure "quality markups" and the welfare consequences of endogenous product quality in U.S. cable television markets. Related papers and extensions to consider multiple product characteristics and dynamics are also discussed. © 2011 Elsevier B.V. All rights reserved.

Li Z.,Kings College London | Kermode J.R.,Kings College London | Kermode J.R.,University of Warwick | De Vita A.,Kings College London
Physical Review Letters | Year: 2015

We present a molecular dynamics scheme which combines first-principles and machine-learning (ML) techniques in a single information-efficient approach. Forces on atoms are either predicted by Bayesian inference or, if necessary, computed by on-the-fly quantum-mechanical (QM) calculations and added to a growing ML database, whose completeness is, thus, never required. As a result, the scheme is accurate and general, while progressively fewer QM calls are needed when a new chemical process is encountered for the second and subsequent times, as demonstrated by tests on crystalline and molten silicon. © Published by the American Physical Society.

Nyman R.A.,Imperial College London | Szymanska M.H.,University of Warwick
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2014

We derive the equation of motion for a Bose-Einstein condensate of photons in a dye-microcavity system, starting from Maxwell's equations. Our theory takes into account mirror shape, Kerr-type intensity-dependent refractive index and incoherent pumping and loss. The resulting equation is remarkably similar to the Gross-Pitaevskii equation for exciton-polariton condensates, despite the different microscopic origins. We calculate the incoherent photoluminescence spectrum of the photon condensate, which shows the Bogoliubov-type excitations around the mean field at thermal equilibrium. Both open- and closed-system models are presented to account for, respectively dissipation and inhomogeneities. Considering realistic parameters and experimental resolution, we estimate that by observing the angle-resolved spectrum of incoherent photoluminescence it is possible to resolve dimensionless interaction parameters of order 10-5, two orders of magnitude below current estimates. Thus we expect that this technique will lead to accurate measurements of the interactions in photon condensates. © 2014 American Physical Society.

Pallen M.J.,University of Warwick
Parasitology | Year: 2014

The term 'shotgun metagenomics' is applied to the direct sequencing of DNA extracted from a sample without culture or target-specific amplification or capture. In diagnostic metagenomics, this approach is applied to clinical samples in the hope of detecting and characterizing pathogens. Here, I provide a conceptual overview, before reviewing several recent promising proof-of-principle applications of metagenomics in virus discovery, analysis of outbreaks and detection of pathogens in contemporary and historical samples. I also evaluate future prospects for diagnostic metagenomics in the light of relentless improvements in sequencing technologies. Copyright © 2014 Cambridge University Press.

Lazic R.,University of Warwick
ACM Transactions on Computational Logic | Year: 2011

A data word is a sequence of pairs of a letter from a finite alphabet and an element from an infinite set, where the latter can only be compared for equality. Safety one-way alternating automata with one register on infinite data words are considered, their nonemptiness is shown to be EXPSPACE-complete, and their inclusion decidable but not primitive recursive. The same complexity bounds are obtained for satisfiability and refinement, respectively, for the safety fragment of linear temporal logic with freeze quantification. Dropping the safety restriction, adding past temporal operators, or adding one more register, each causes undecidability.© 2011 ACM.

Royle P.,University of Warwick
Systematic reviews | Year: 2013

Systematic reviews are important for informing clinical practice and health policy. The aim of this study was to examine the bibliometrics of systematic reviews and to determine the amount of variance in citations predicted by the journal impact factor (JIF) alone and combined with several other characteristics. We conducted a bibliometric analysis of 1,261 systematic reviews published in 2008 and the citations to them in the Scopus database from 2008 to June 2012. Potential predictors of the citation impact of the reviews were examined using descriptive, univariate and multiple regression analysis. The mean number of citations per review over four years was 26.5 (SD ± 29.9) or 6.6 citations per review per year. The mean JIF of the journals in which the reviews were published was 4.3 (SD ± 4.2). We found that 17% of the reviews accounted for 50% of the total citations and 1.6% of the reviews were not cited. The number of authors was correlated with the number of citations (r = 0.215, P < 0.001). Higher numbers of citations were associated with the following characteristics: first author from the United States (36.5 citations), an ICD-10 chapter heading of Neoplasms (31.8 citations), type of intervention classified as Investigation, Diagnostics or Screening (34.7 citations) and having an international collaboration (32.1 citations). The JIF alone explained more than half of the variation in citations (R(2) = 0.59) in univariate analysis. Adjusting for both JIF and type of intervention increased the R2 value to 0.81. Fourteen percent of reviews published in the top quartile of JIFs (≥ 5.16) received citations in the bottom quartile (eight or fewer), whereas 9% of reviews published in the lowest JIF quartile (≤ 2.06) received citations in the top quartile (34 or more). Six percent of reviews in journals with no JIF were also in the first quartile of citations. The JIF predicted over half of the variation in citations to the systematic reviews. However, the distribution of citations was markedly skewed. Some reviews in journals with low JIFs were well-cited and others in higher JIF journals received relatively few citations; hence the JIF did not accurately represent the number of citations to individual systematic reviews.

Coja-Oghlan A.,University of Warwick
Proceedings of the Annual ACM-SIAM Symposium on Discrete Algorithms | Year: 2011

Let φ be a uniformly distributed random k-SAT formula with n variables and m clauses. Non-constructive arguments show that φ is satisfiable for clause/variable ratios m/n ≤ rk ∼ 2k ln 2 with high probability (Achlioptas, Moore: SICOMP 2006; Achlioptas, Peres: J. AMS 2004). Yet no efficient algorithm is know to find a satisfying assignment for densities as low as m/n ∼ rk · In(k)/k with a non-vanishing probability. In fact, the density m/n ∼ rk · In(k)/k seems to form a barrier for a broad class of local search algorithms (Achlioptas, Coja-Oghlan: FOCS 2008). On the basis of deep but non-rigorous statistical mechanics considerations, a message passing algorithm called belief propagation guided decimation for solving random k-SAT has been forward (Mézard, Parisi, Zecchina: Science 2002; Braunstein, Mézard, Zecchina: RSA 2005). Experiments suggest that the algorithm might succeed for densities very close to rk for k = 3,4,5 (Kroc, Sabharwal, Selman: SAC 2009). Furnishing the first rigorous analysis of belief propagation guided decimation on random k-SAT, the present paper shows that the algorithm fails to find a satisfying assignment already for m/n ≥ ρ · rk/k, for a constant ρ > 0 independent of k.

Bivins R.,University of Warwick
Social History of Medicine | Year: 2013

While investment and popular enthusiasm have fuelled significant growth in the history of medicine since the 1980s, it remains by some metrics well outside of the historical mainstream. Yet developments in the history of medicine could offer traction to historians more generally. Through its close critical attention to power, embodiment and hegemonic institutions and knowledges, the history of medicine also presents a unique perspective from which to interrogate 'postcolonialism'. Here, post-war British examples demonstrate the potential of a medical and postcolonial lens for historians exploring policy making, immigration or identity. In this period, civil servants, biomedical researchers, policy makers, and publics including migrants actively shaped medical and governmental responses to an apparently novel phenomenon: the mass migration to Britain of its former tropical subjects. Postcolonial analysis uncovers new models of community, and highlights the importance of the late twentieth-century and the post-imperial city as sites of historiographic and theoretical development. © 2012 The Author 2012.

Gutierrez-Marcos J.F.,University of Warwick | Dickinson H.G.,University of Oxford
Plant and Cell Physiology | Year: 2012

Monoecious flowering plants produce both microgametophytes (pollen) and megagametophytes (embryo sacs) containing the male and female gametes, respectively, which participate in double fertilization. Much is known about cellular and developmental processes giving rise to these reproductive structures and the formation of gametes. However, little is known about the role played by changes in the epigenome in dynamically shaping these defining events during plant sexual reproduction. This has in part been hampered by the inaccessibility of these structures-especially the female gametes, which are embedded within the female reproductive tissues of the plant sporophyte. However, with the recent development of new cellular isolation technologies that can be coupled to next-generation sequencing, a new wave of epigenomic studies indicate that an intricate epigenetic regulation takes place during the formation of male and female reproductive lineages. In this mini review, we assess the fast growing body of evidence for the epigenetic regulation of the developmental fate and function of plant gametes. We describe how small interfereing RNAs and DNA methylation machinery play a part in setting up unique epigenetic landscapes in different gametes, which may be responsible for their different fates and functions during fertilization. Collectively these studies will shed light on the dynamic epigenomic landscape of plant gametes or 'epigametes' and help to answer important unresolved questions on the sexual reproduction of flowering plants, especially those underpinning the formation of two products of fertilization, the embryo and the endosperm. © 2012 The Author.

Motivation: High-throughput nucleotide sequencing technologies provide large amounts of quantitative genomic data at nucleotide resolution, which are important for the present and future biomedical researches; for example differential analysis of base-level RNA expression data will improve our understanding of transcriptome, including both coding and non-coding genes. However, most studies of these data have relied on existing genome annotations and thus are limited to the analysis of known transcripts. Results: In this article, we propose a novel method based on a marked point process model to find differentially expressed genomic regions of arbitrary length without using genome annotations. The presented method conducts a statistical test for differential analysis in regions of various lengths at each nucleotide and searches the optimal configuration of the regions by using a Monte Carlo simulation. We applied the proposed method to both synthetic and real genomic data, and their results demonstrate the effectiveness of our method. © The Author(s) 2012. Published by Oxford University Press.

Mottram J.T.,University of Warwick
Structural Engineer | Year: 2011

Reviewing the current status towards the exploitation of fibre reinforced polymers (FRPs) in structural engineering the author considers the benefits and challenges for using performance based design with this newer construction material. This paper reports historical case studies in the context of explaining how processing technologies and design know-how have slowly been developing, and perhaps even leading to a level of maturity. By way of the review of FRP components and structures it is found that we do not yet possess the prescriptive rules that dominate the current execution of civil engineering works. One outcome from the review is to identify that such rules will be necessary to allow routine design of frame structures of universal (standard) FRP shapes. The author introduces the benefits and challenges towards the adoption of Performance Based Design (PBD) and finds that targeted research and development has/is using the PBD philosophy to produce bespoke FRP components and systems towards a growing number of applications in structural engineering. © J.Toby Mottram.

Seiden G.,Max Planck Institute for Dynamics and Self-Organization | Seiden G.,Weizmann Institute of Science | Thomas P.J.,University of Warwick
Reviews of Modern Physics | Year: 2011

Rotating-drum flows span a variety of research areas, ranging from physics of granular matter through hydrodynamics of suspensions to pure liquid coating flows. Recent years have seen an intensified scientific activity associated with this unique geometrical configuration, which has contributed to our understanding of related subjects such as avalanches in granules and segregation in suspensions. The existing literature related to rotating-drum flows is reviewed, highlighting similarities and differences between the various flow realizations. Scaling laws expressing the importance of different mechanisms underlying the observed phenomena have been focused on. An emphasis is placed on pattern formation phenomena. Rotating-drum flows exhibit stationary patterns as well as traveling and oscillating patterns; they exhibit reversible transitions as well as hysteresis. Apart from the predominant cylindrical configuration, this review covers recent work done with tumblers having other geometries, such as the sphere and the Hele-Shaw cell. © 2011 American Physical Society.

Forrest M.D.,University of Warwick
PLoS ONE | Year: 2013

In vitro, Purkinje cell behaviour is sometimes studied in a dissociated soma preparation in which the dendritic projection has been cleaved. A fraction of these dissociated somas spontaneously burst. The mechanism of this bursting is incompletely understood. We have constructed a biophysical Purkinje soma model, guided and constrained by experimental reports in the literature, that can replicate the somatically driven bursting pattern and which hypothesises Persistent Na+ current (INaP) to be its burst initiator and SK K+ current (ISK) to be its burst terminator. © 2013 Michael D.

This paper presents an investigation on the correlation between surface topography and its mechanical properties measured by a novel multi-function tribological probe microscope (TPM) at the micro/nanometre level. Four surface functions of topography, friction, nano-hardness and Young's modulus are measured over a range of materials, on a point-by-point basis using the TPM. The capability of multi-function mapping of the TPM allows the cross correlation to be carried out, in order to investigate the influence of one function on another, especially the surface topography's effect on its mechanical properties. A general negative correlation between surface topography and hardness/Young's modulus has been found for most homogeneous surfaces, which indicates a modulation effect of surface geometrical features on its mechanical properties. © 2012 Elsevier B.V.

Browning D.F.,University of Birmingham | Grainger D.C.,University of Warwick | Busby S.J.W.,University of Birmingham
Current Opinion in Microbiology | Year: 2010

Bacterial nucleoid-associated proteins play a key role in the organisation, replication, segregation, repair and expression of bacterial chromosomes. Here, we review some recent progress in our understanding of the effects of these proteins on DNA and their biological role, focussing mainly on Escherichia coli and its chromosome. Certain nucleoid-associated proteins also regulate transcription initiation at specific promoters, and work in concert with dedicated transcription factors to regulate gene expression in response to growth phase and environmental change. Some specific examples, involving the E. coli IHF and Fis proteins, that illustrate new principles, are described in detail. © 2010 Elsevier Ltd.

Glasser L.,Curtin University Australia | Jenkins H.D.B.,University of Warwick
Journal of Chemical and Engineering Data | Year: 2011

Thermodynamics, as both thermochemistry and thermophysics, is fundamental and central to the science of matter and, in particular, of condensed materials. While extensive data resources for thermodynamic quantities do exist, none of the experimental, simulation, or theoretical studies can keep pace with the rate of synthesis of new materials or provide reliable data for hypothesized materials. Correlation methods can fill this gap. We describe a range of recently developed correlation methods that rely on volume to predict thermodynamic quantities. In parallel with these, thermodynamic difference rules, which describe how properties of materials (say, of a group of solvates) may be inferred from corresponding properties of materials that neighbor them in composition, have recently been reviewed. © 2010 American Chemical Society.

Ellis R.J.,University of Warwick
Philosophical transactions of the Royal Society of London. Series B, Biological sciences | Year: 2013

The historical origins and current interpretation of the molecular chaperone concept are presented, with the emphasis on the distinction between folding chaperones and assembly chaperones. Definitions of some basic terms in this field are offered and misconceptions pointed out. Two examples of assembly chaperone are discussed in more detail: the role of numerous histone chaperones in fundamental nuclear processes and the co-operation of assembly chaperones with folding chaperones in the production of the world's most important enzyme.

Dame R.T.,Leiden University | Kalmykowa O.J.,Leiden University | Grainger D.C.,University of Warwick | Grainger D.C.,University of Birmingham
PLoS Genetics | Year: 2011

The Escherichia coli chromosome is organized into four macrodomains, the function and organisation of which are poorly understood. In this review we focus on the MatP, SeqA, and SlmA proteins that have recently been identified as the first examples of factors with macrodomain-specific DNA-binding properties. In particular, we review the evidence that these factors contribute towards the control of chromosome replication and segregation by specifically targeting subregions of the genome and contributing towards their unique properties. Genome sequence analysis of multiple related bacteria, including pathogenic species, reveals that macrodomain-specific distribution of SeqA, SlmA, and MatP is conserved, suggesting common principles of chromosome organisation in these organisms. This discovery of proteins with macrodomain-specific binding properties hints that there are other proteins with similar specificity yet to be unveiled. We discuss the roles of the proteins identified to date as well as strategies that may be employed to discover new factors. © 2011 Dame et al.

Sparkes I.,Oxford Brookes University | Hawes C.,Oxford Brookes University | Frigerio L.,University of Warwick
Current Opinion in Plant Biology | Year: 2011

The endoplasmic reticulum (ER) in higher plants performs many important functions, yet our understanding of how its intricate network shape and dynamics relate to function is very limited. Recent work has begun to unpick key molecular players in the generation of the pleomorphic, highly dynamic ER network structure that pervades the entire cytoplasm. ER movement is acto-myosin dependent. ER shape is dependent on RHD3 (Root Hair Defective 3) and a family of proteins called reticulons. The major challenge that lies ahead is understanding how factors that control ER shape and movement are regulated and how this relates to the numerous functions of the ER. © 2011 Elsevier Ltd.

Crump R.E.,University of Warwick | Medley G.F.,London School of Hygiene and Tropical Medicine
Parasites and Vectors | Year: 2015

Background: The number of new leprosy cases reported annually is falling worldwide, but remains relatively high in some populations. Because of the long and variable periods between infection, onset of disease, and diagnosis, the recently detected cases are a reflection of infection many years earlier. Estimation of the numbers of sub-clinical and clinical infections would be useful for management of elimination programmes. Back-calculation is a methodology that could provide estimates of prevalence of undiagnosed infections, future diagnoses and the effectiveness of control. Methods: A basic back-calculation model to investigate the infection dynamics of leprosy has been developed using Markov Chain Monte Carlo in a Bayesian context. The incidence of infection and the detection delay both vary with calendar time. Public data from Thailand are used to demonstrate the results that are obtained as the incidence of diagnosed cases falls. Results: The results show that the underlying burden of infection and short-term future predictions of cases can be estimated with a simple model. The downward trend in new leprosy cases in Thailand is expected to continue. In 2015 the predicted total number of undiagnosed sub-clinical and clinical infections is 1,168 (846-1,546) of which 466 (381-563) are expected to be clinical infections. Conclusions: Bayesian back-calculation has great potential to provide estimates of numbers of individuals in health/infection states that are as yet unobserved. Predictions of future cases provides a quantitative measure of understanding for programme managers and evaluators. We will continue to develop the approach, and suggest that it might be useful for other NTD in which incidence of diagnosis is not an immediate measure of infection. © 2015 Crump and Medley.

Kwon Y.,Leiden University | Lai S.C.S.,Leiden University | Lai S.C.S.,University of Warwick | Rodriguez P.,Leiden University | Koper M.T.M.,Leiden University
Journal of the American Chemical Society | Year: 2011

On the basis of a comparison of the oxidation activity of a series of similar alcohols with varying pKa on gold electrodes in alkaline solution, we find that the first deprotonation is base catalyzed, and the second deprotonation is fast but gold catalyzed. The base catalysis follows a Hammett-type correlation with pKa, and dominates overall reactivity for a series of similar alcohols. The high oxidation activity on gold compared to platinum for some of the alcohols is related to the high resistance of gold toward the formation of poisoning surface oxides. These results indicate that base catalysis is the main driver behind the high oxidation activity of many organic fuels on fuel cell anodes in alkaline media, and not the catalyst interaction with hydroxide. © 2011 American Chemical Society.

D'Elia L.,University of Naples Federico II | Barba G.,National Research Council Italy | Cappuccio F.P.,University of Warwick | Strazzullo P.,University of Naples Federico II
Journal of the American College of Cardiology | Year: 2011

Objectives: The objective of this study was to assess the relation between the level of habitual potassium intake and the incidence of cardiovascular disease (CVD). Background: Prospective cohort studies have evaluated the relationship between habitual potassium intake and incidence of vascular disease, but their results have not been not entirely consistent. Methods: We performed a systematic search for prospective studies published, without language restrictions (1966 to December 2009). Criteria for inclusion were prospective adult population study, assessment of baseline potassium intake, assessment of vascular events as outcome, and follow-up of at least 4 years. For each study, relative risks (RRs) and 95% confidence intervals (CIs) were extracted and pooled using a random-effect model, weighted for the inverse of the variance. Heterogeneity, publication bias, subgroup, and meta-regression analyses were performed. Results: Eleven studies were identified, providing 15 cohort samples that included 247,510 male and female participants (follow-up 5 to 19 years), 7,066 strokes, 3,058 coronary heart disease (CHD) events, and 2,497 total CVD events. Potassium intake was assessed by 24-h dietary recall (n = 2), food frequency questionnaire (n = 6), or 24-h urinary excretion (n = 3). In the pooled analysis, a 1.64-g (42 mmol) per day higher potassium intake was associated with a 21% lower risk of stroke (RR: 0.79; 95% CI: 0.68 to 0.90; p = 0.0007), with a trend toward lower risk of CHD and total CVD that attained statistical significance after the exclusion of a single cohort, based on sensitivity analysis (RR: 0.93; 95% CI: 0.87 to 0.99; p = 0.03 and RR: 0.74; 95% CI: 0.60 to 0.91; p = 0.0037). Conclusions: Higher dietary potassium intake is associated with lower rates of stroke and might also reduce the risk of CHD and total CVD. These results support recommendations for higher consumption of potassium-rich foods to prevent vascular diseases. © 2011 American College of Cardiology Foundation.

Krupski A.,University of Warwick
Journal of Physics Condensed Matter | Year: 2014

In this work we briefly review recent investigations concerning the growth morphology of thin metallic films on the Mo(110) and Ni3Al(111) surfaces, and Fe and copper phthalocyanine (C32H16N 8Cu) on the Al2O3/Ni3Al(111) surface. Comparison of Ag, Au, Sn, and Pb growth on the Mo(110) surface has shown a number of similarities between these adsorption systems, except that surface alloy formation has only been observed in the case of Sn and Au. In the Pb/Mo(110) and Pb/Ni3Al(111) adsorption systems selective formation of uniform Pb island heights during metal thin film growth has been observed and interpreted in terms of quantum size effects. Furthermore, our studies showed that Al2O3 on Ni3Al(111) exhibits a large superstructure in which the unit cell has a commensurate relation with the substrate lattice. In addition, copper phthalocyanine chemisorbed weakly onto an ultra-thin Al2O3 film on Ni3Al(111) and showed a poor template effect of the Al2O3/Ni3Al(111) system. In the case of iron cluster growth on Al2O 3/Ni3Al(111) the nucleation sites were independent of deposition temperature, yet the cluster shape showed a dependence. In this system, Fe clusters formed a regular hexagonal lattice on the Al 2O3/Ni3Al(111). © 2014 IOP Publishing Ltd.

Qureshi J.,University of East London | Mottram J.T.,University of Warwick
Journal of Composites for Construction | Year: 2014

Physical testing is used to characterize the structural properties of beam-to-column joints, comprising pultruded fiber-reinforced polymer (FRP) H-shapes of depth 203 mm, connected by 128 mm-long web cleats and two M16 bolts per leg. Testing is performed on two batches of nominally identical specimens. One batch had web cleats of pultruded FRP and the other had structural steel. The structural behavior of the joints is based on their moment-rotation responses, failure modes, and serviceability vertical deflection limits. Joints with FRP cleats failed by delamination cracking at the top of the cleats, and when the cleats were of steel, the FRP failure occurred inside the column members. Neither failure mode is reported in the design manuals from pultruders. At the onset of the FRP damage, it was found that the steel joints were twice as stiff as the FRP joints. On the basis of a characteristic (damage) rotation, calculated in accordance with Eurocode 0, the serviceability deflection limits are established to be span/300 and span/650 for the joints with FRP and steel cleats, respectively. This finding suggests that appropriate deflection limits, in relation to cleated connections, should be proposed in manufactures' design manuals and relative design standards and design codes. Failure to address the serviceability, by the engineer of record, could lead to unreliable designs. © 2013 American Society of Civil Engineers.

Francis L.J.,University of Warwick
Mental Health, Religion and Culture | Year: 2013

In his analysis of the construct "implicit religion" Edward Bailey speaks of those individuals "who believe in Christianity" but who do not display the behaviours of explicit religion, like church attendance. A recent research tradition has tried to operationalise this understanding of implicit religion by studying those who believe that they can be a Christian without going to church. A longer established research tradition has demonstrated the association between explicit religiosity and an enhanced sense of purpose in life. The aim of the present study is to test the hypothesis that implicit religiosity (in the sense of believing that you can be a Christian without going to church) is also associated with an enhanced sense of purpose in life. Data provided by a sample of 25,825 13- to 15-year-old adolescents support this hypothesis. In turn these findings support the notion that implicit religion (in the sense operationalised by this study) fulfils some functions similar to those fulfilled by explicit religion. © 2013 © 2013 Taylor & Francis.

Rutledge P.J.,University of Sydney | Challis G.L.,University of Warwick
Nature Reviews Microbiology | Year: 2015

Microorganisms produce a wealth of structurally diverse specialized metabolites with a remarkable range of biological activities and a wide variety of applications in medicine and agriculture, such as the treatment of infectious diseases and cancer, and the prevention of crop damage. Genomics has revealed that many microorganisms have far greater potential to produce specialized metabolites than was thought from classic bioactivity screens; however, realizing this potential has been hampered by the fact that many specialized metabolite biosynthetic gene clusters (BGCs) are not expressed in laboratory cultures. In this Review, we discuss the strategies that have been developed in bacteria and fungi to identify and induce the expression of such silent BGCs, and we briefly summarize methods for the isolation and structural characterization of their metabolic products. © 2015 Macmillan Publishers Limited. All rights reserved.

Hadjipantelis P.Z.,University of Warwick
The Journal of the Acoustical Society of America | Year: 2012

A model for fundamental frequency (F0, or commonly pitch) employing a functional principal component (FPC) analysis framework is presented. The model is applied to Mandarin Chinese; this Sino-Tibetan language is rich in pitch-related information as the relative pitch curve is specified for most syllables in the lexicon. The approach yields a quantification of the influence carried by each identified component in relation to original tonal content, without formulating any assumptions on the shape of the tonal components. The original five speaker corpus is preprocessed using a locally weighted least squares smoother to produce F0 curves. These smoothed curves are then utilized as input for the computation of FPC scores and their corresponding eigenfunctions. These scores are analyzed in a series of penalized mixed effect models, through which meaningful categorical prototypes are built. The prototypes appear to confirm known tonal characteristics of the language, as well as suggest the presence of a sinusoid tonal component that is previously undocumented.

Coveney C.M.,University of Warwick
Sociology of Health and Illness | Year: 2014

This article contributes to literature on the sociology of sleep by exploring the sleeping practices and subjective sleep experiences of two social groups: shift workers and students. It draws on data, collected in the UK from 25 semi-structured interviews, to discuss the complex ways in which working patterns and social activities impact upon experiences and expectations of sleep in our wired awake world. The data show that, typically, sleep is valued and considered to be important for health, general wellbeing, appearance and physical and cognitive functioning. However, sleep time is often cut back on in favour of work demands and social activities. While shift workers described their efforts to fit in an adequate amount of sleep per 24-hour period, for students, the adoption of a flexible sleep routine was thought to be favourable for maintaining a work-social life balance. Collectively, respondents reported using a wide range of strategies, techniques, technologies and practices to encourage, overcome or delay sleep(iness) and boost, promote or enhance wakefulness/alertness at socially desirable times. The analysis demonstrates how social context impacts not only on how we come to think about sleep and understand it, but also how we manage or self-regulate our sleeping patterns. © 2013 The Author. Sociology of Health & Illness © 2013 Foundation for the Sociology of Health & Illness/John Wiley & Sons Ltd.

Czumaj A.,University of Warwick
Proceedings of the Annual ACM Symposium on Theory of Computing | Year: 2015

We consider the problem of designing a simple, oblivious scheme to generate (almost) random permutations. We use the concept of switching networks and show that almost every switching network of logarithmic depth can be used to almost randomly permute any set of (1 - ε)n elements with any ε > 0 (that is, gives an almost (1 - ε)n-wise independent permutation). Furthermore, we show that the result still holds for every switching network of logarithmic depth that has some special expansion properties, leading to an explicit construction of such networks. Our result can be also extended to an explicit construction of a switching network of depth O(log2 n) and with O(nlogn) switches that almost randomly permutes any set of n elements. We also discuss basic applications of these results in cryptography. Our results are obtained using a non-trivial coupling approach to study mixing times of Markov chains which allows us to reduce the problem to some random walk-like problem on expanders.

Jennings K.R.,University of Warwick
International Journal of Mass Spectrometry | Year: 2014

Since the first experiments in which high energy collision induced decomposition was used to determine structural information nearly fifty years ago, a variety of different methods of ion activation have been developed each of which has its own advantages and disadvantages. The development of "soft" ionisation techniques and their use to ionise biological species of very high molecular weights has resulted in ion activation techniques and tandem mass spectrometry becoming one of the most important fields of interest. Developments in mass analysers have also changed the emphasis placed on different activation techniques and opened up new opportunities and challenges. Although collision induced decomposition (CID) has been widely used, it has a number of drawbacks and new ion activation methods have been developed, the most widely used being electron capture decomposition (ECD) and electron transfer decomposition (ETD), each of which has its own particular advantages. Surface induced decomposition (SID) has been less widely adopted because it requires commercial instrumentation to be modified. Applications of these four techniques are discussed with special reference to peptide and protein sequencing. © 2014 Elsevier B.V. All rights reserved.

Li C.-T.,University of Warwick
IEEE Transactions on Information Forensics and Security | Year: 2010

Sensor pattern noises (SPNs), extracted from digital images to serve as the fingerprints of imaging devices, have been proved as an effective way for digital device identification. However, as we demonstrate in this work, the limitation of the current method of extracting SPNs is that the SPNs extracted from images can be severely contaminated by details from scenes, and as a result, the identification rate is unsatisfactory unless images of a large size are used. In this work, we propose a novel approach for attenuating the influence of details from scenes on SPNs so as to improve the device identification rate of the identifier. The hypothesis underlying our SPN enhancement method is that the stronger a signal component in an SPN is, the less trustworthy the component should be, and thus should be attenuated. This hypothesis suggests that an enhanced SPN can be obtained by assigning weighting factors inversely proportional to the magnitude of the SPN components. © 2010 IEEE.

Sorensen T.B.,University of Warwick
Proceedings of the ACM Conference on Electronic Commerce | Year: 2012

We provide the first pivoting-type algorithm that computes an exact proper equilibrium of a bimatrix game. This is achieved by using Lemke's algorithm to solve a linear complementarity problem (LCP) of polynomial size. This also proves that computing a simple refinement of proper equilibria for bimatrix game is PPAD-complete. The algorithm also computes a witness in the form of a parameterized strategy that is an epsilon-proper equilibrium for any given sufficiently small ε, allowing polynomial-time verification of the properties of the refined equilibrium. The same technique can be applied to matrix games (two-player zero-sum), thereby computing a parameterized epsilon-proper strategy in polynomial time using linear programming. © 2012 ACM.

Corre C.,University of Warwick
Chemistry and Biology | Year: 2013

The TetR family of microbial transcription factors directly control the expression of a diverse range of genes in bacteria by sensing specific ligands. In this issue of Chemistry & and Biology, Cuthbertson and colleagues used phylogenomics to guide the identification of TetR-like protein cognate ligands and revealed a novel inducible antibiotic resistance mechanism. © 2013 Elsevier Ltd.

Clarke A.,University of Warwick
Quality & safety in health care | Year: 2010

To assess effectiveness of guidelines for referral for elective surgical assessment. Systematic review with descriptive synthesis. Medline, EMBASE, CINAHL and Cochrane database up to 2008. Hand searches of journals and websites. Studies evaluated guidelines for referral from primary to secondary care, for elective surgical assessment for adults. Appropriateness of referral (usually measured as guideline compliance) including clinical appropriateness, appropriateness of destination and of pre-referral management (eg, diagnostic investigations), general practitioner knowledge of referral appropriateness, referral rates, health outcomes and costs. 24 eligible studies (5 randomised control trials, 6 cohort, 13 case series) included guidelines from UK, Europe, Canada and the USA for referral for musculoskeletal, urological, ENT, gynaecology, general surgical and ophthalmological conditions. Interventions varied from complex ("one-stop shops") to simple guidelines. Four randomized control trials reported increases in appropriateness of pre-referral care (diagnostic investigations and treatment). No evidence was found for effects on practitioner knowledge. Mixed evidence was reported on rates of referral and costs (rates and costs increased, decreased or stayed the same). Two studies reported on health outcomes finding no change. Guidelines for elective surgical referral can improve appropriateness of care by improving pre-referral investigation and treatment, but there is no strong evidence in favour of other beneficial effects.

Rowlands S.,University of Warwick
Best Practice and Research: Clinical Obstetrics and Gynaecology | Year: 2010

This article begins with an overview of teenage pregnancy within a social context. Data are then presented on conceptions and repeat conceptions in teenagers. Social predictors of repeat teenage pregnancy are grouped according to social ecological theory. A brief summary of prevention of teenage pregnancy in general is followed by a detailed analysis of studies of interventions designed to prevent repeat pregnancy that reached specific quality criteria. The results of some systematic reviewsshow no significant overall effect on repeat pregnancy, whereas others show an overall significant reduction. Youth development programmes are shown in some cases to lower pregnancy rates but in other cases to have no effect or even to increase them. Features of secondary prevention programmes more likely to be successful are highlighted. © 2010 Elsevier Ltd.

Francis L.J.,University of Warwick
Mental Health, Religion and Culture | Year: 2010

Beit-Hallahmi and Argyle concluded that individual differences in religiosity are inversely related to psychoticism but independent of extraversion and neuroticism. The aim of the present study is to test the generalizability of that conclusion within the context of Eysenck's dimensional model of personality by distinguishing between different conceptualizations of religiosity and by distinguishing between different overall levels of religiosity in the sample. A total of 517 undergraduate students in Wales completed the short-form of the Revised Eysenck Personality Questionnaire together with the New Indices of Religious Orientation. The data demonstrated that in the sample as a whole, intrinsic religious orientation was associated with low psychoticism scores, but independent of extraversion scores and neuroticism scores; that extrinsic religious orientation was associated with low psychoticism scores and high neuroticism scores, but independent of extraversion scores; and that quest religious orientation was associated with high neuroticism scores and low extraversion scores, but independent of psychoticism scores. The pattern of relationships changed, however, when separate analyses were conducted among weekly churchgoers and among individuals who never attended church. These data suggest that the pattern of relationship between personality and religion may vary both according to the form of religiosity assessed and according to the samples being studied. The conclusion is drawn that Beit-Hallahmi and Argyle's conclusion is misleading unless nuanced in terms of the aspects of religiosity and the populations to which it applies. © 2010 Taylor & Francis.

Miller M.A.,University of Warwick
Journal of Clinical Sleep Medicine | Year: 2011

There is emerging evidence suggesting that disturbances in sleep and sleep disorders play a role in the morbidity of chronic conditions including obesity and hypertension as well as in the development of type-2 diabetes. This brief review examines the role of inflammation in the development of atherosclerosis. Furthermore, it outlines the utility of inflammatory markers and, in particular, adhesion molecules as biomarkers for cardiovascular risk and the factors that affect their level in the circulation. It then discusses the relationship between sleep and markers of inflammation and the role of sleep in immune function.

Timofeeva Y.,University of Warwick
Physica D: Nonlinear Phenomena | Year: 2010

Dendrites, the major components of neurons, have many different types of branching structures and are involved in receiving and integrating thousands of synaptic inputs from other neurons. Dendritic spines with excitable channels can be present in large densities on the dendrites of many cells. The recently proposed Spike-Diffuse-Spike (SDS) model that is described by a system of point hot-spots (with an integrate-and-fire process) embedded throughout a passive tree has been shown to provide a reasonable caricature of a dendritic tree with supra-threshold dynamics. Interestingly, real dendrites equipped with voltage-gated ion channels can exhibit not only supra-threshold responses, but also sub-threshold dynamics. This sub-threshold resonant-like oscillatory behaviour has already been shown to be adequately described by a quasi-active membrane. In this paper we introduce a mathematical model of a branched dendritic tree based upon a generalisation of the SDS model where the active spines are assumed to be distributed along a quasi-active dendritic structure. We demonstrate how solitary and periodic travelling wave solutions can be constructed for both continuous and discrete spine distributions. In both cases the speed of such waves is calculated as a function of system parameters. We also illustrate that the model can be naturally generalised to an arbitrary branched dendritic geometry whilst remaining computationally simple. The spatio-temporal patterns of neuronal activity are shown to be significantly influenced by the properties of the quasi-active membrane. Active (sub- and supra-threshold) properties of dendrites are known to vary considerably among cell types and animal species, and this theoretical framework can be used in studying the combined role of complex dendritic morphologies and active conductances in rich neuronal dynamics. © 2010 Elsevier B.V. All rights reserved.

This paper discusses the potential of the synthetic-aperture method in digital holography to increase the resolution, to perform high accuracy deformation measurement, and to obtain a three-dimensional topology map. The synthetic aperture method is realized by moving the camera with a motorized x-y stage. In this way a greater sensor area can be obtained resulting in a larger numerical aperture (NA). A larger NA enables a more detailed reconstruction combined with a smaller depth of field. The depth of field can be increased by applying the extended depth of field method, which yields an in-focus reconstruction of all longitudinal object regions. Moreover, a topology map of the object can be obtained. © 2010 Optical Society of America.

Allen P.,University of Warwick
Electronic Journal of Combinatorics | Year: 2010

By using the Szemerédi Regularity Lemma [10], Alon and Sudakov [1] recently extended the classical Andŕasfai-Erdo{double acute}s-Sós theorem [2] to cover general graphs. We prove, without using the Regularity Lemma, that the following stronger statement is true. Given any (r+1)-partite graph H whose smallest part has t vertices, there exists a constant C such that for any given ε > 0 and sufficiently large n the following is true. Whenever G is an n-vertex graph with minimum degree δ(G) ≥ (1 - 3/3r-1+ ε)n, either G contains H, or we can delete f(n,H)≤6 Cn 2-1/t edges from G to obtain an r-partite graph. Further, we are able to determine the correct order of magnitude of f(n,H) in terms of the Zarankiewicz extremal function.

Quigley D.,University of Warwick
Journal of Chemical Physics | Year: 2014

A simple Ising-like model for the stacking thermodynamics of ice 1 is constructed for nuclei in supercooled water, and combined with classical nucleation theory. For relative stabilities of cubic and hexagonal ice I within the range of experimental estimates, this predicts critical nuclei are stacking disordered at strong sub-cooling, consistent with recent experiments. At higher temperatures nucleation of pure hexagonal ice is recovered. Lattice-switching Monte-Carlo is applied to accurately compute the relative stability of cubic and hexagonal ice for the popular mW model of water. Results demonstrate that this model fails to adequately capture the relative energetics of the two polytypes, leading to stacking disorder at all temperatures. © 2014 Author(s).

Innovation is accomplished through collaborations of thousands of researchers embedded in a growing international knowledge community, where some hyperlinked actors can strongly impact the diffusion of innovation tools within the community. Few extant studies have empirically inspected the following issues which govern the influence of hyperlinked actors: (1) how the heterogeneity in their actor attributes regulates the volume of their influences; (2) how the nature of connectivity of these actors impacts the volume of their influences. Our current study intends to address this gap by examining the diffusion of innovation tools among life scientists around the world in a time span of 16 years, and we find that for hyperlinked scientists: (1) heavy usage and high variety of usage behaviors have stronger relationship with diffusion rate than light usage and low variety of usage; (2) light usage and high variety usage behaviors have stronger relationship with extent of diffusion than heavy usage and low variety usage; (3) international links have stronger relationship with both the rate and extent of diffusion than domestic links. Our work contributes to innovation research by providing a sharper understanding on the social contagion mechanism in innovation diffusion within global knowledge communities. © 2012 Elsevier Ltd. All rights reserved.

Adriaens A.,Ghent University | Dowsett M.,University of Warwick
Accounts of Chemical Research | Year: 2010

Corrosion is a major source of degradation in heritage metal objects, and any remedial measures are subject to a strong (Western) ethic that favors conservation as opposed to restoration. Accordingly, major scientific challenges exist for developing appropriate treatment methods to stabilize and protect artifacts after they are recovered from an archaeological site, both before and during their display or storage in a museum. Because inappropriate treatments can cause irreversible damage to irreplaceable objects, it is crucial that the chemical processes involved are fully understood and characterized before any preservation work is undertaken. In this regard, large infrastructural facilities such as synchrotrons, neutron sources, and particle accelerators provide a wealth of analytical possibilities, unavailable in smaller scale laboratories. In general, the intensity of the radiation available allows measurements on a short time scale or with high spatial resolution (or both), so heterogeneous changes induced by a chemical process can be recorded while they occur. The penetrative nature of the radiation (e.g., X-rays, protons, or neutrons) also allows a sample to be studied in air. If necessary, complete artifacts (such as paintings or statuettes) can be examined. In situ analysis in a controlled environment, such as a liquid or corrosive atmosphere, also becomes an exciting possibility. Finally, there are many complementary techniques (local atomic structure or crystal structure determination, macroscopic 3-D imaging (tomographies), imaging chemical analysis, and so on) so the many distinct details of a problem can be thoroughly explored. In this Account, we discuss the application of this general philosophy to studies of corrosion and its prevention in cultural heritage metals, focusing on our recent work on copper alloys. More specifically, we use synchrotron-based techniques to evaluate the use of corrosion potential measurements as a possible monitoring method for copper-based objects recovered from marine environments. The extraction of chlorides from such artifacts is a process that must take place before the artifacts are put on display or stored, because air exposure of untreated metal will result in severe damage or loss in as little as a few weeks. Chloride is removed by soaking the artifact for up to two years in tap water or dilute sodium sesquicarbonate, with regular solution changes. Our research supports the effectiveness of this treatment for thin nantokite (copper(I) chloride) layers, but it raises questions for copper hydroxychlorides (atacamite and paratacamite), especially when these minerals are trapped in fissures. Electrochemical parameters such as the corrosion potential are shown to be insensitive to the physical presence of large hydroxychloride coverages if they overlie a cuprite (Cu2O) layer. X-ray absorption spectroscopy proves to be a good monitor for the chloride in solution over the working electrode, whereas X-ray diffraction offers the potential for real-time measurement of the surface chloride composition. In principle, the two techniques together offer the possibility of monitoring surface and fluid levels simultaneously. © 2010 American Chemical Society.

Arnold D.,University of Warwick
ISIS | Year: 2013

This essay uses the seminal figure of Jawaharlal Nehru to interrogate the nature and representation of science in modern India. The problem posed by Nehruvian science-the conflict between (yet simultaneity of) science as both universal phenomenon and local effect-lies at the heart of current debates about what science means for the non-West. The problematic of Nehruvian science can be accessed through Nehru's own speeches and writings, but also through the wider project of science with which he identified- critiquing colonialism, forging India's place in the modern world, marrying intellectual endeavor with practical nation building. The essay makes a case for looking at Nehruvian science as a way of structuring the problem of postcolonial science, particularly in relation to understanding the authority of science and its evaluation in terms of its capacity to deliver socioeconomic change. © 2013 by The History of Science Society All rights reserved.

Busi R.,University of Western Australia | Neve P.,University of Warwick | Powles S.,University of Western Australia
Evolutionary Applications | Year: 2013

The interaction between environment and genetic traits under selection is the basis of evolution. In this study, we have investigated the genetic basis of herbicide resistance in a highly characterized initially herbicide-susceptible Lolium rigidum population recurrently selected with low (below recommended label) doses of the herbicide diclofop-methyl. We report the variability in herbicide resistance levels observed in F1 families and the segregation of resistance observed in F2 and back-cross (BC) families. The selected herbicide resistance phenotypic trait(s) appear to be under complex polygenic control. The estimation of the effective minimum number of genes (NE), depending on the herbicide dose used, reveals at least three resistance genes had been enriched. A joint scaling test indicates that an additive-dominance model best explains gene interactions in parental, F1, F2 and BC families. The Mendelian study of six F2 and two BC segregating families confirmed involvement of more than one resistance gene. Cross-pollinated L. rigidum under selection at low herbicide dose can rapidly evolve polygenic broad-spectrum herbicide resistance by quantitative accumulation of additive genes of small effect. This can be minimized by using herbicides at the recommended dose which causes high mortality acting outside the normal range of phenotypic variation for herbicide susceptibility. Journal compilation © 2013 Blackwell Publishing Ltd62 February 2013 10.1111/j.1752-4571.2012.00282.x Original Article Original Articles © 2012 Blackwell Publishing Ltd. This is an open access article under the terms of the Creative Commons Attribution Non Commercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Utili S.,University of Warwick | Utili S.,University of Oxford
Geotechnique | Year: 2013

A full set of solutions for the stability of homogeneous c, φ{symbol} slopes with cracks has been obtained by the kinematic method of limit analysis, providing rigorous upper bounds to the true collapse values for any value of engineering interest of φ{symbol}, the inclination of the slope, and the depth and location of cracks. Previous stability analyses of slopes with cracks are based mainly on limit equilibrium methods, which are not rigorous, and are limited in their capacity for analysis, since they usually require the user to assume a crack depth and location in the slope. Conversely, numerical methods (e.g. finite-element method) struggle to deal with the presence of cracks in the slope, because of the discontinuities introduced in both the static and kinematic fields by the presence of cracks. In this paper, solutions are provided in a general form considering cases of both dry and water-filled cracks. Critical failure mechanisms are determined for cracks of known depth but unspecified location, cracks of known location but unknown depth, and cracks of unspecified location and depth. The upper bounds are achieved by assuming a rigid rotational mechanism (logarithmic spiral failure line). It is also shown that the values obtained provide a significant improvement on the currently available upper bounds based on planar failure mechanisms, providing a reduction in the stability factor of up to 85%. Charts of solutions are presented in dimensionless form for ease of use by practitioners. © 2013 Thomas Telford Ltd.

Troisi A.,University of Warwick
Advances in Polymer Science | Year: 2010

The traditional theories of charge transport in ordered organic semiconductors are reviewed and their limitations discussed. The recent contributions of computational chemistry to the understanding of the parameters that determine the charge mobility in bulk semiconductors are analyzed in detail. The effect of thermal motions on the electronic wavefunction and the effect of strong off-diagonal electron-phonon coupling are identified as essential ingredients for the proper description of the charge dynamics. The development of suitable methods to compute the charge mobility taking into account these new computational results is reviewed, with special emphasis on the models that allow the prediction of the structure-property relationship. The available experimental evidence is compared with the predictions made by the most recent models. © 2009 Springer-Verlag Berlin Heidelberg.

Smith C.M.,University of Warwick | Colquhoun M.C.,Resuscitation Council UK
Resuscitation | Year: 2015

Background: Out-of-hospital cardiac arrest (OHCA) in children and adolescents is rare, with a minority of cases occurring at school. When OHCA does occur at school it is more likely to affect an adult than a student. Developing comprehensive strategies to treat cardiac arrest occurring at schools would be helped by accurate data regarding its epidemiology. Methods: A systematic review was undertaken. An electronic search strategy of MEDLINE and EMBASE databases was devised and relevant papers reporting data on school-based OHCA incidence and/or outcome in both adults and children were identified. Further articles were obtained from the bibliographies of these papers and from related articles. Results: Nine studies were included in the systematic review. Cardiac arrest incidence was one per 23.8-284.1 schools per year. Cardiac arrest incidence amongst students, reported in some studies, was 0.17-4.4 per 100,000 students per year. Studies also reported, although not universally, rates of witnessed OHCA (25.0-97.2%), VF (57.4-67.6%), bystander CPR (25.0-94.4%) and automated external defibrillator (AED) use (23.4-91.5%). Survival to hospital discharge or at one month was between 31.9% and 71.2%. Conclusion: Cardiac arrest in schools is rare, and more likely to occur in adults than children. Outcomes are better than OHCA occurring at other locations, probably due to the high proportion of witnessed arrests and high rates of bystander CPR. It is likely that school-based AEDs will rarely be needed, but have the potential to make a dramatic impact on outcome. © 2015 Elsevier Ireland Ltd.

Zhang H.L.,Catholic University of Leuven | Baeyens J.,University of Warwick | Degreve J.,Catholic University of Leuven | Caceres G.,Adolfo Ibanez University
Renewable and Sustainable Energy Reviews | Year: 2013

Concentrated solar power plants (CSPs) are gaining increasing interest, mostly as parabolic trough collectors (PTC) or solar tower collectors (STC). Notwithstanding CSP benefits, the daily and monthly variation of the solar irradiation flux is a main drawback. Despite the approximate match between hours of the day where solar radiation and energy demand peak, CSPs experience short term variations on cloudy days and cannot provide energy during night hours unless incorporating thermal energy storage (TES) and/or backup systems (BS) to operate continuously. To determine the optimum design and operation of the CSP throughout the year, whilst defining the required TES and/or BS, an accurate estimation of the daily solar irradiation is needed. Local solar irradiation data are mostly only available as monthly averages, and a predictive conversion into hourly data and direct irradiation is needed to provide a more accurate input into the CSP design. The paper (i) briefly reviews CSP technologies and STC advantages; (ii) presents a methodology to predict hourly beam (direct) irradiation from available monthly averages, based upon combined previous literature findings and available meteorological data; (iii) illustrates predictions for different selected STC locations; and finally (iv) describes the use of the predictions in simulating the required plant configuration of an optimum STC. The methodology and results demonstrate the potential of CSPs in general, whilst also defining the design background of STC plants. © 2013 Elsevier Ltd.

Sampath K.,University of Warwick | Robertson E.J.,University of Oxford
Open Biology | Year: 2016

Nodal is an evolutionarily conserved member of the transforming growth factor-β (TGF-β) superfamily of secreted signalling factors. Nodal factors are known to play key roles in embryonic development and asymmetry in a variety of organisms ranging from hydra and sea urchins to fish, mice and humans. In addition to embryonic patterning, Nodal signalling is required for maintenance of human embryonic stem cell pluripotency and mis-regulated Nodal signalling has been found associated with tumour metastases. Therefore, precise and timely regulation of this pathway is essential. Here, we discuss recent evidence from sea urchins, frogs, fish, mice and humans that show a role for transcriptional and translational repression of Nodal signalling during early development. © 2016 The Authors.

The United Nations Special Representative of the Secretary-General on Business and Human Rights, Professor John Ruggie, has constructed a new international framework, which is set to become the cornerstone for all action on human rights and business at the international level. The principle of human rights due diligence (HRDD) is the central component of the corporate duty to respect human rights within that framework. This article argues that Ruggie's HRDD principle contains the majority of the core procedural elements that a reasonable human rights impact assessment (HRIA) process should incorporate. It is likely that the majority of corporations will adopt HRIA as a mechanism for meeting their due diligence responsibilities. However, in the context of the contentious debate around corporate human rights performance, the current state of the art in HRIA gives rise to concerns about the credibility and robustness of likely practice. Additional requirements are therefore essential if HRDD is to have a significant impact on corporate human rights performance - requirements in relation to transparency; external participation and verification; and independent monitoring and review. © 2013 Copyright The Author(s).

Wright L.B.,University of Warwick | Walsh T.R.,Deakin University
Physical Chemistry Chemical Physics | Year: 2013

Harnessing the properties of biomolecules, such as peptides, adsorbed on inorganic surfaces is of interest to many cross-disciplinary areas of science, ranging from biomineralisation to nanomedicine. Key to advancing research in this area is determination of the peptide conformation(s) in its adsorbed state, at the aqueous interface. Molecular simulation is one such approach for accomplishing this goal. In this respect, use of temperature-based replica-exchange molecular dynamics (T-REMD) can yield enhanced sampling of the interfacial conformations, but does so at great computational expense, chiefly because of the need to include an explicit representation of water at the interface. Here, we investigate a number of more economical variations on REMD, chiefly those based on Replica Exchange with Solvent Tempering (REST), using the aqueous quartz-binding peptide S1-(100) α-quartz interfacial system as a benchmark. We also incorporate additional implementation details specifically targeted at improving sampling of biomolecules at interfaces. We find the REST-based variants yield configurational sampling of the peptide-surface system comparable with T-REMD, at a fraction of the computational time and resource. Our findings also deliver novel insights into the binding behaviour of the S1 peptide at the quartz (100) surface that are consistent with available experimental data. © 2013 the Owner Societies.

The literature has generally not grappled with complex decisionmaking structures within organizations like the UN. Special representatives of the Secretary-General can act as norm arbitrators in the UN system, generating new practices by weighing against each other the conflicting norms that guide peacekeeping. Practices from the field, crystallized through the actions of SRSGs, constitute a bottom-up source of influence on UN norm change processes. SRSGs enjoy relative independence and physical distance from UN headquarters. With backgrounds often from diplomatic careers, plus relative autonomy and interpretations of the UN, they can wield influence thanks to a certain level of decentralized authority and their personal prestige.

Frey B.S.,University of Warwick | Frey B.S.,University of Zurich
Science | Year: 2011

The pursuit of happiness can have concrete benefits for well-being.

Kettell S.,University of Warwick
British Journal of Politics and International Relations | Year: 2013

The sphere of foreign policy provides a hitherto unexplored field for studying the applicability of interpretivist concepts and concerns. Here, a particularly useful topic of analysis is that of discursive strategies; namely, the way in which government figures seek to legitimise and justify their decisions and behaviour. Operating at the intersection between beliefs, traditions and dilemmas, the examination of foreign policy discourse offers key insights into a variety of important issues, including political communication and media management. This article considers these themes by examining the changing form of New Labour's discursive strategy on Britain's role in the war on terror during the period of Tony Blair's premiership from 2001 to mid-2007. Charting the various shifts to have taken place in this discursive landscape, the article analyses the way in which these changes were driven by dilemmas resulting from tensions between practical developments and the discursive claims made about them. This shows how various rationalities within the sphere of British politics were operationalised and sustained, and how numerous 'dilemmas of discourse' were addressed. © 2012 Political Studies Association.

Ma H.,Nanjing University | Troisi A.,University of Warwick
Advanced Materials | Year: 2014

Direct optical excitation of long-range charge-transfer (CT) states in organic photovoltaics is shown to be feasible, a fact that is ascribed to the very low but non-vanishing oscillator strength of each individual transition and the much higher density of states (DOS) as compared with their short-range counterparts. This finding provides a new framework to interpret the low-energy absorption spectra of photovoltaic devices and to correlate this property with the optoelectronic conversion process in working devices. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Heath-Kelly C.,University of Warwick
British Journal of Politics and International Relations | Year: 2013

This article interrogates the production of the 'radicalisation' discourse which underpins efforts to govern 'terrorism' pre-emptively through the UK's PREVENT strategy. British counter-terrorism currently relies upon the invention of 'radicalisation' and related knowledge about transitions to 'terrorism' to undertake governance of communities rendered suspicious. The article argues that such conceptions make terrorism knowable and governable through conceptions of risk. Radicalisation knowledge provides a counterfactual to terrorism-enabling governmental intervention in its supposed production. It makes the future actionable. However, while the deployment of 'radicalisation' functions to make terrorism pre-emptively governable and knowable, it also renders PREVENT unstable by simultaneously presenting 'vulnerability indicators' for radicalisation as threats to the wider collective-these conducts are framed as both 'at risk' and 'risky', both vulnerable and dangerous. This instability speaks to ad hoc production of the radicalisation discourse by scholarly and policy-making communities for the governance of terrorism through radicalisation knowledge. This article analyses the production of the radicalisation discourse to explore its performance as a form of risk governance within British counter-terrorism. © 2012 Political Studies Association.

Carpenter M.,University of Warwick
Landscape and Urban Planning | Year: 2013

The article traces the recent 'discovery' of the importance of walking in urban green spaces to health to its historical roots, and situates it within its discursive and political-economic context. It shows, using the UK as a case example, how the nineteenth century urban parks movements had public health as one of its key objectives, linked to a hegemonic middle class project of promoting order and 'rational recreation' to the working classes. It then shows that as health problems and understandings changed, along with broader political-economic shifts, park aims shifted from enhancing 'health' to promoting 'fitness'. With the growth of modern notions of citizenship, decline of infectious disease, and the rise of the biomedical model in the welfare state era, parks ceased to be seen as means to health and were transformed into municipal services. After the oil crises of the 1970s and the rise of Thatcherism, they went into decline, though from the 1990s there were political efforts to revive them as part of a wider set of sustainable urban policies, and growing preoccupations with the health costs of a sedentary and obese society. In this context, the article provides a critical commentary on the science and policy of individualist discourses of 'green walking' and health. It argues for a broad 'ecological health promotion' approach, using economic crisis as an opportunity to move forward in ways consistent with environmental justice and an emancipatory 'capabilities' approach to public health. © 2013 Elsevier B.V.

Habershon S.,University of Warwick
Journal of Chemical Theory and Computation | Year: 2016

In a recent article [J. Chem. Phys. 2015, 143, 094106], we introduced a novel graph-based sampling scheme which can be used to generate chemical reaction paths in many-atom systems in an efficient and highly automated manner. The main goal of this work is to demonstrate how this approach, when combined with direct kinetic modeling, can be used to determine the mechanism and phenomenological rate law of a complex catalytic cycle, namely cobalt-catalyzed hydroformylation of ethene. Our graph-based sampling scheme generates 31 unique chemical products and 32 unique chemical reaction pathways; these sampled structures and reaction paths enable automated construction of a kinetic network model of the catalytic system when combined with density functional theory (DFT) calculations of free energies and resultant transition-state theory rate constants. Direct simulations of this kinetic network across a range of initial reactant concentrations enables determination of both the reaction mechanism and the associated rate law in an automated fashion, without the need for either presupposing a mechanism or making steady-state approximations in kinetic analysis. Most importantly, we find that the reaction mechanism which emerges from these simulations is exactly that originally proposed by Heck and Breslow; furthermore, the simulated rate law is also consistent with previous experimental and computational studies, exhibiting a complex dependence on carbon monoxide pressure. While the inherent errors of using DFT simulations to model chemical reactivity limit the quantitative accuracy of our calculated rates, this work confirms that our automated simulation strategy enables direct analysis of catalytic mechanisms from first principles. © 2016 American Chemical Society.

Watson M.,University of Warwick
British Journal of Politics and International Relations | Year: 2013

New Labour staked much politically on its ability to enact a trouble-free shift in underlying economic subjectivities so as to nurture responsibly self-sufficient welfare citizens. This policy began merely as the requirement for benefit claimants to become active worker subjects in the interests of enhanced employability. More problematically from the perspective of its own macroeconomic policy, it ended as the requirement for as many people as possible to become much more tension-prone active worker-saver-investor subjects in the interests of enhanced private pension insurance. The article charts the collapse of New Labour's reputation for economic governing competence as these latter subjects' accumulated asset wealth threatened to implode during the recent financial crisis. In its last days the Brown government inadvertently placed itself in the paradoxical position of being able to defend either the financial interests of responsibly self-sufficient welfare citizens or its own reputation for macroeconomic responsibility, but not both. British Journal of Politics and International Relations © 2012 Political Studies Association.

Griffin X.L.,University of Warwick
Cochrane database of systematic reviews (Online) | Year: 2011

Delayed union and non-union of fractures are a considerable cause of morbidity to patients. Laboratory studies have shown that electromagnetic fields can stimulate the formation of new bone, indicating a potential role for electromagnetic stimulation in the treatment of fractures that have failed to heal. To assess the effects of electromagnetic stimulation for treating delayed union or non-union of long bone fractures in adults. We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (May 2010), the Cochrane Central Register of Controlled Trials (in The Cochrane Library 2010, Issue 2), MEDLINE (1966 to May 2010) and EMBASE (1980 to 2010 Week 20), trial registers and reference lists of articles. Randomised controlled trials evaluating electromagnetic field stimulation for the treatment of delayed union or non-union of long bones in adults. Two authors independently selected studies and performed data extraction and risk of bias assessment. Treatment effects were assessed using risk ratios and, where appropriate, data were pooled using a random-effects model. Four studies, involving 125 participants, were included. Three studies evaluated the effects of pulsed electromagnetic fields and one study, capacitive coupled electric fields. Participants with delayed union and non-union of the long bones were included, but most data related to non-union of the tibia. Although all studies were blinded randomised placebo-controlled trials, each study had limitations.The primary measure of the clinical effectiveness of electromagnetic field stimulation was the proportion of participants whose fractures had united at a fixed time point. The overall pooled effect size was small and not statistically significant (risk ratio 1.96; 95% confidence interval 0.86 to 4.48; 4 trials). There was substantial clinical and statistical heterogeneity in this pooled analysis (I(2) = 58%). A sensitivity analysis conducted to determine the effect of multiple follow-up time-points on the heterogeneity amongst the studies showed that the effect size remained non-significant at 24 weeks (risk ratio 1.61; 95% confidence interval 0.74 to 3.54; 3 trials), with similar heterogeneity (I(2) = 57%).There was no reduction in pain found in two trials. No study reported functional outcome measures. One trial reported two minor complications resulting from treatment. Though the available evidence suggests that electromagnetic field stimulation may offer some benefit in the treatment of delayed union and non-union of long bone fractures, it is inconclusive and insufficient to inform current practice. More definitive conclusions on treatment effect await further well-conducted randomised controlled trials.

Lochner M.,University of Warwick | Lummis S.C.R.,University of Cambridge
Biophysical Journal | Year: 2010

The 5-HT3 receptor is a member of the Cys-loop family of transmitter receptors. It can function as a homopentamer (5-HT3A-only subunits) or as a heteropentamer. The 5-HT3AB receptor is the best characterized heteropentamer. This receptor differs from a homopentamer in its kinetics, voltage dependence, and single-channel conductance, but its pharmacology is similar. To understand the contribution of the 5-HT3B subunit to the binding site, we created homology models of 5-HT3AB receptors and docked 5-HT and granisetron into AB, BA, and BB interfaces. To test whether ligands bind in any or all of these interfaces, we mutated amino acids that are important for agonist and antagonist binding in the 5-HT3A subunit to their corresponding residues in the 5-HT3B subunit and vice versa. Changes in [ 3H]granisetron binding affinity (Kd) and 5-HT EC 50 were determined using receptors expressed in HEK-293 cells and Xenopus oocytes, respectively. For all A-to-B mutant receptors, except T181N, antagonist binding was altered or eliminated. Functional studies revealed that either the receptors were nonfunctional or the EC50 values were increased. In B-to-A mutant receptors there were no changes in Kd although EC50 values and Hill slopes, except for N170T mutant receptors, were similar to those for 5-HT3A receptors. Thus, the experimental data do not support a contribution of the 5-HT3B subunit to the binding pocket, and we conclude that both 5-HT and granisetron bind to an AA binding site in the heteromeric 5-HT3AB receptor. © 2010 by the Biophysical Society.

Ormandy D.,University of Warwick | Ezratty V.,Electricite de France
Energy Policy | Year: 2012

There are many references to the WHO guidance on thermal comfort in housing, but not to the original source material. Based on archive material, this paper gives the evidential basis for the WHO guidance. It then reports on evidence that some groups may be more susceptible to high or low indoor temperatures than others. It examines different methods for measuring thermal comfort, such as air temperature measurement, assessing residents' perception, and predicting satisfaction. Resident's perception was used effectively in the WHO LARES project, showing that self-reported poor health was significantly associated with poor thermal comfort. Tools to inform strategies directed at dealing with cold homes and fuel poverty are considered, including Energy Performance Certificates, Fuel Poverty Indicators, and the English Housing Health and Safety Rating System. Conclusions from a WHO Workshop on Housing, Energy and Thermal Comfort are also summarised. The WHO view of thermal comfort, which is driven by protecting health from both high and low indoor temperatures, should be recognised in energy efficiency, fuel poverty and climate change strategies. While this is a major challenge, it could provide both health gains for individuals, and economic benefits for society. © 2011 Elsevier Ltd.

Papers in the literature have thus far overlooked the projected increase in U.S. diesel car share when looking at asymmetries in petroleum pricing. This paper addresses this issue by comparing retail gasoline and diesel prices in order to see whether they rise faster than they fall given the price of their upstream input, crude oil. This phenomenon has been termed in the literature as "Rockets and Feathers." We apply the threshold vector error correction model (TVECM) of Hansen and Seo (2002) which has not yet been applied in the literature. We account for the 2008 structural break to crude oil and petroleum prices by splitting the sample using evidence from the recent structural break unit root test of Kim and Perron (2009). Both markets seem to price symmetrically before the 2008 break, but we find evidence of asymmetric pricing after 2008 in diesel prices, and not in gasoline prices. Given that the diesel market is small relative to the gasoline market and therefore more open to price exploitation, the ongoing cost increases associated with the policy of switching to Ultra Low Sulphur diesel (ULSD) from 2006 to 2010 could be at the heart of this asymmetry. With this in mind, the U.S. Federal Trade Commission should monitor diesel prices as the market share grows, in order to ensure that consumers are not adversely affected. © 2012 Elsevier B.V.

Lozin V.V.,University of Warwick
Theoretical Computer Science | Year: 2010

We study the following question: given a finite collection of graphs G 1,...,Gk, is the dominating set problem polynomial-time solvable in the class of (G1,...,Gk)-free graphs? In this paper, we prove the existence of an efficient algorithm that answers this question for k=2. © 2010 Elsevier B.V. All rights reserved.

Griffin X.L.,University of Warwick
Cochrane database of systematic reviews (Online) | Year: 2012

The morbidity and socioeconomic costs of fractures are considerable. The length of time to healing is an important factor in determining a patient's recovery after a fracture. Ultrasound may have a therapeutic role in reducing the time to union after fracture. To assess the effects of low intensity ultrasound (LIPUS), high intensity focused ultrasound (HIFUS) and extracorporeal shockwave therapies (ECSW) as part of the treatment of acute fractures in adults. We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (December 2011), the Cochrane Central Register of Controlled Trials (in The Cochrane Library 2011, Issue 4), MEDLINE (1950 to November Week 3 2011), EMBASE (1980 to 2011 Week 49), trial registers and reference lists of articles. Randomised controlled trials evaluating ultrasound treatment in the management of acute fractures in adults. Studies including participants over 18 years of age with acute fractures, reporting functional outcomes, time to union, non-union, secondary procedures such as for fixation or delayed or non-union, adverse effects, pain, costs or patient adherence were included. Two authors independently extracted data from the included studies. Treatment effects were assessed using mean differences or risk ratios and, where there was substantial heterogeneity, pooled using a random-effects model. Results from 'worst case' analyses, which gave more conservative estimates of treatment effects for time to fracture union, are reported in preference to those from 'as reported' analyses. Twelve studies, involving 622 participants with 648 fractures, were included. Eight studies were randomised placebo-controlled trials, two studies were randomised controlled trials without placebo controls, one study was a quasi-randomised placebo controlled trial and the remaining study was a quasi-randomised controlled trial without placebo control. Eleven trials tested LIPUS and one trial tested ECSW. Four trials included participants with conservatively treated upper limb complete fractures and six trials included participants with lower limb complete fractures; these were surgically fixed in four trials. The remaining two trials reported results for conservatively treated tibial stress fractures.Very limited data from two complete fracture studies showed no difference between ultrasound and placebo control in functional outcome. Pooled estimates from two studies found LIPUS did not significantly affect the time to return to training or duty in soldiers or midshipmen with stress fractures (mean difference -8.55 days, 95% CI -22.71 to 5.61).Based on a 'worst case' analysis, which adjusted for incomplete data, pooled results from eight heterogeneous studies showed no statistically significant reduction in time to union of complete fractures treated with LIPUS (standardised mean difference -0.47, 95% CI -1.14 to 0.20). This result could include a clinically important benefit or harm, and should be seen in the context of the highly significant statistical heterogeneity (I 2 = 90%). This heterogeneity was not explained by the a priori subgroup analyses (upper limb versus lower limb fracture, smoking status). An additional subgroup analysis comparing conservatively and operatively treated fractures raised the possibility that LIPUS may be effective in reducing healing time in conservatively managed fractures, but the test for subgroup differences did not confirm a significant difference between the subgroups.Pooled results from eight trials reporting proportion of delayed union or non-union showed no significant difference between LIPUS and control. Adverse effects directly associated with LIPUS and associated devices were found to be few and minor, and compliance with treatment was generally good. One study reporting on pain scores found no difference between groups at eight weeks.One quasi-randomised study (59 fractures) found no significant difference between ECSW and no-placebo control groups in non-union at 12 months (risk ratio 0.56, 95% CI 0.15 to 2.01). There was a clinically small but statistically significant difference in the visual analogue scores for pain in favour of ECSW at three month follow-up. The only reported complication was infection, with no significant difference between the two groups. While a potential benefit of ultrasound for the treatment of acute fractures in adults cannot be ruled out, the currently available evidence from a set of clinically heterogeneous trials is insufficient to support the routine use of this intervention in clinical practice. Future trials should record functional outcomes and follow-up all trial participants.

Zhang K.,University of Warwick
Agriculture, Ecosystems and Environment | Year: 2010

Agro-hydrological models have widely been used for optimizing resources use in agriculture for maximum crop growth and minimum environmental consequences. The SMCR_N model is a recently developed, process-based, multi-crop and management-oriented agro-hydrological model for water and nitrogen dynamics in the soil-crop system, and has been validated against data from field experiments over a range of vegetable crops. In this study, the model is further tested against the comprehensive measured datasets from field experiments conducted under different circumstances on wheat. It has been found that given the proper parameterization of the simple growth equation, which worked well with vegetable crops, the model was able to simulate wheat growth accurately. The predicted relative root length density distributions at various development stages agreed with the measurements and those modeled by alternative approaches in the literature. The explicit hydrological algorithm for the basic equations governing water and nitrogen transport in soil performed well. Compared with other conventional numerical schemes, the algorithm used in the study was much simpler and easy to implement. The simulated spatial-temporal soil water content was in good agreement with the measurements, given the information of groundwater table was known. The model was also capable of reproducing the data of nitrogen uptake and soil mineral nitrogen concentration measured at depths and at time intervals. This indicates that the key equations for various processes governing water and nitrogen dynamics in the soil-wheat system were correctly formulated, and the model was properly parameterized. The results from this exercise, together with the model's previous validation over 16 vegetable crops, make the model a good candidate to be used for water and nitrogen management for growing diverse crops. © 2010 Elsevier B.V. All rights reserved.

Fuller D.Q.,University College London | Willcox G.,French National Center for Scientific Research | Allaby R.G.,University of Warwick
Journal of Experimental Botany | Year: 2012

The origins of agriculture in the Near East has been associated with a 'core area', located in south-eastern Turkey, in which all major crops were brought into domestication within the same local domestication system operated by a single cultural group. Such an origin leads to a scenario of rapid invention of agriculture by a select cultural group and typically monophyletic origins for most crops. Surprisingly, support for a core area has never been directly tested with archaeological evidence. Over the past decade a large amount of new archaeological and genetic evidence has been discovered which brings new light on the origins of agriculture. In this review, this new evidence was brought together in order to evaluate whether a core region of origin is supported. Evidence shows that origins began earlier than previously assumed, and included 'false starts' and dead ends that involved many more species than the typical eight founder crops associated with the core area. The rates at which domestication syndrome traits became fixed were generally slow, rather than rapid, and occurred over a geographically wide range that included the North and South Levant as well as the core area. Finally, a survey of the estimated ages of archaeological sites and the onset of domestication indicates that the domestication process was ongoing in parallel outside of the core area earlier than within it. Overall, evidence suggests a scenario in which crops were domesticated slowly in different locations around the Near East rather than emanating from a core area. © 2011 The Author.

Woolley M.J.,University of Warwick
Journal of the Royal Society, Interface / the Royal Society | Year: 2013

The calcitonin gene-related peptide (CGRP) receptor is a complex of a calcitonin receptor-like receptor (CLR), which is a family B G-protein-coupled receptor (GPCR) and receptor activity modifying protein 1. The role of the second extracellular loop (ECL2) of CLR in binding CGRP and coupling to Gs was investigated using a combination of mutagenesis and modelling. An alanine scan of residues 271-294 of CLR showed that the ability of CGRP to produce cAMP was impaired by point mutations at 13 residues; most of these also impaired the response to adrenomedullin (AM). These data were used to select probable ECL2-modelled conformations that are involved in agonist binding, allowing the identification of the likely contacts between the peptide and receptor. The implications of the most likely structures for receptor activation are discussed.

Carbone P.,University of Manchester | Troisi A.,University of Warwick
Journal of Physical Chemistry Letters | Year: 2014

We study the charge diffusion of semiconducting polymer bulk using simplified coarse grained models to investigate the relation between charge diffusion coefficient and the characteristics time of intrachain and interchain hopping, τ1 and τ2. We consider the process of charge diffusion in several standard models of polymer chains (rigid chain, Gaussian chain, worm-like chain), and we achieve an analytical expression for the diffusion coefficient in terms of the characteristic times and the geometric parameters defining the chain models. The diffusion depends only on the intrachain hopping for the rigid chain and on the geometric average of intrachain and interchain hopping times for the Gaussian chain (the least rigid model), with an analytical interpolation available between two limits. The model highlights the importance of large persistence lengths for improved transport properties. In all cases, it is incorrect to consider the slower interchain hopping as the rate-determining step for the charge transport. © 2014 American Chemical Society.

Dove A.P.,University of Warwick
ACS Macro Letters | Year: 2012

Organic catalysis in ring-opening polymerization (ROP) has become a powerful alternative to more traditional metal-based catalysts. The field has developed to a point at which there are not only excellent low cost and easy to use organocatalysts for day-to-day polymerizations, but the ability to precisely control the synthesis of advanced polymer architectures and ROP monomers that are extremely challenging to polymerize with other catalysts now exists. This viewpoint article will highlight the key advances in organocatalyst design with the aim of encouraging the wider application of organic catalysts in ROP. © 2012 American Chemical Society.

Ricketts J.,University of Warwick
Journal of Child Psychology and Psychiatry and Allied Disciplines | Year: 2011

Background: Deficits in reading airment (SLI), Down syndrome (DS) and autism spectrum disorders (ASD). Methods: In this review (based on a search of the ISI Web of Knowledge database to 2011), the Simple View of Reading is used as a framework for considering reading comprehension in these groups. Conclusions: There is substantial evidence for reading comprehension impairments in SLI and growing evidence that weaknesses in this domain are common in DS and ASD. Further, in these groups reading comprehension is typically more impaired than word recognition. However, there is also evidence that some children and adolescents with DS, ASD and a history of SLI develop reading comprehension and word recognition skills at or above the age appropriate level. This review of the literature indicates that factors including word recognition, oral language, nonverbal ability and working memory may explain reading comprehension difficulties in SLI, DS and ASD. In addition, it highlights methodological issues, implications of poor reading comprehension and fruitful areas for future research. © 2011 Association for Child and Adolescent Mental Health.

Spinal metastases can lead to significant morbidity and reduction in quality of life due to spinal cord compression (SCC). Between 5% and 20% of patients with spinal metastases develop metastatic spinal cord compression during the course of their disease. An early study estimated average survival for patients with SCC to be between 3 and 7 months, with a 36% probability of survival to 12 months. An understanding of the natural history and early diagnosis of spinal metastases and prediction of collapse of the metastatic vertebrae are important. To undertake a systematic review to examine the natural history of metastatic spinal lesions and to identify patients at high risk of vertebral fracture and SCC.In the prostate cancer studies, tumour grade, metastatic load and time on hormone therapy were associated with increased risk of SCC. In one study, risk of SCC before death was 24%, and 2.37 times greater with a Gleason score ≥ 7 than with a score of < 7 (p= 0.003). Other research found that patients with six or more bone lesions were at greater risk of SCC than those with fewer than six lesions [odds ratio (OR) 2.9, 95% confidence interval (CI) 1.012 to 8.35, p= 0.047]. For breast cancer patients who received a computerised tomography (CT) scan for suspected SCC, multiple logistic regression in one study identified four independent variables predictive of a positive test: bone metastases ≥ 2 years (OR 3.0 95% CI 1.2 to 7.6; p= 0.02); metastatic disease at initial diagnosis (OR 3.4, 95% CI 1.0 to 11.4; p= 0.05); objective weakness (OR 3.8, 95% CI 1.5 to 9.5; p= 0.005); and vertebral compression fracture on spine radiograph (OR 2.6, 95% CI 1.0 to 6.5; p= 0.05). A further study on mixed cancers, among patients who received surgery for SCC, reported that vertebral body compression fractures were associated with presurgery chemotherapy (OR 2.283, 95% CI 1.064 to 4.898; p= 0.03), cancer type [primary breast cancer (OR 4.179, 95% CI 1.457 to 11.983; p= 0.008)], thoracic involvement (OR 3.505, 95% CI 1.343 to 9.143; p= 0.01) and anterior cord compression (OR 3.213, 95% CI 1.416 to 7.293; p= 0.005). Many of the included studies provided limited information about patient populations and selection criteria and they varied in methodological quality, rigour and transparency. Several studies identified type of cancer (e.g. breast, lung or prostate cancer) as a significant factor in predicting SCC, but it remains difficult to determine the risk differential partly because of residual bias. Consideration of quantitative results from the studies does not easily allow generation of a coherent numerical summary, studies were heterogeneous especially with regard to population, results were not consistent between studies, and study results almost universally lacked corroboration from other independent studies. No studies were found which examined natural history. Overall burden of metastatic disease, confirmed metastatic bone involvement and immediate symptomatology suggestive of spinal column involvement are already well known as factors for metastatic SCC, vertebral collapse or progression of vertebral collapse. Although we identified a large number of additional possible prognostic factors, those which currently offer the most potential are unclear. Current clinical consensus favours magnetic resonance imaging and CT imaging modalities for the investigation of SCC and vertebral fracture. Future research should concentrate on: (1) prospective randomised designs to establish clinical and quality-of-life outcomes and cost-effectiveness of identification and treatment of patients at high risk of vertebral collapse and SCC; (2) Service Delivery and Organisation research on magnetic resonance imaging (MRI) scans and scanning (in tandem with research studies on use of MRI to monitor progression) in order to understand best methods for maximising use of MRI scanners; and (3) investigation of prognostic algorithms to calculate probability of a specified event using high-quality prospective studies, involving defined populations, randomly selected and clearly identified samples, and with blinding of investigators. This report was commissioned by the National Institute for Health Research Health Technology Assessment Programme NIHR HTA Programme as project number HTA 10/91/01.

Greer K.,University of Warwick
Annals of the Association of American Geographers | Year: 2013

In the mid-nineteenth century, the Mediterranean region emerged as a crucial site for the security of the British Empire route to India and South Asia, especially with the opening of the Suez Canal in 1869. Military stations served as trans-imperial sites, connecting Britain to India through the flow of military manpower, commodities, information, and bodily experiences across the empire from 1850 through 1880. By examining the material remnants of the "avian imperial archive" (avian lists, bird skins, eggs, travel writing), I demonstrate how British military ornithology helped to materialize imaginatively and empirically the British Mediterranean as a transitional region for the physical and cultural acclimatization of British officers en route to and from India and to extend British imperial interests into North Africa. As this article reveals, the production of zoogeography by British military officers in the Mediterranean was coconstituted by imperial military geopolitics. © 2013 Copyright Taylor and Francis Group, LLC.

Hebenstreit D.,University of Warwick
Biology | Year: 2012

RNA-sequencing (RNA-seq) has become the tool of choice for transcriptomics. Several recent studies demonstrate its successful adaption to single cell analysis. This allows new biological insights into cell differentiation, cell-to-cell variation and gene regulation, and how these aspects depend on each other. Here, I review the current single cell RNA-seq (scRNA-seq) efforts and discuss experimental protocols, challenges and potentials. © 2012 by the authors; licensee MDPI, Basel, Switzerland.

Critoph R.E.,University of Warwick
International Journal of Refrigeration | Year: 2012

The history of solid sorption systems is long, since in 1823 Faraday used the adsorption of large amounts of ammonia into silver chloride as the basis of a thermal compressor to obtain and study liquid ammonia. With the ammoniated silver chloride in one leg of a sealed bent glass tube, upon heating he could repeatedly drive out and condense pure liquid ammonia in the other leg. In 1915, Dunsford reserved a patent for ammonia sorption reactors using ammonium nitrate as adsorbent, particularly for use in marine applications. Environmental and energy cost concerns led to new research and development of smaller scale products for a range of applications such as vehicle air conditioning, solar air conditioning and heat pumping in the modern era. With ever increasing energy prices and greater environmental concerns customers can see much more serious commercial interest and so it may now be the time for adsorption refrigeration and heat pumping to join the mainstream technologies.

Dunbar G.,University of Warwick
Appetite | Year: 2010

Task-based interface design principles (TBI) were evaluated as a framework for designing effective nutritional labels. In two experiments a total of 123 people assembled a packed lunch, selecting components using labels in GDA or TBI format, or when given only the names of the foods. Study 1 found that a GDA label helped people make healthier choices than the product name alone, but that for a number of types of food, most people would make the same decision with or without a GDA label. Moreover, decisions were much faster when made with the name alone. Study 2 introduced a TBI label in the context of the more specific task of keeping the salt in the lunch under 1. g. TBI and GDA labels reduced salt equally, but only the TBI label was as quick as the name alone. Labels that are aligned with people's specific objectives are more efficient. TBI is a potentially useful framework, that can be deployed using mobile computing. © 2010 Elsevier Ltd.

Vorberger J.,Max Planck Institute for the Physics of Complex Systems | Gericke D.O.,University of Warwick
High Energy Density Physics | Year: 2014

We evaluate various analytical models for the electron-ion energy transfer and compare the results to data from molecular dynamics (MD) simulations. The models tested include energy transfer via strong binary collisions, Landau-Spitzer rates with different choices for the cut-off parameters in the Coulomb logarithm, rates based on Fermi's golden rule (FGR) and theories taking coupled collective modes (CM) into account. In search of a model easy to apply, we first analyze different approximations of the FGR energy transfer rate. Then, we investigate several numerical studies using MD simulations and try to uncover CM effects in the data obtained. Most MD data published so far, except one study by Murillo etal. [23], show no distinct CM effects and, thus, can be interpreted within a FGR or binary collision approach. We show that this finding is related to the parameter regime, in particular the initial temperature difference, considered in these investigations. © 2013 Elsevier B.V.

Thapper J.,Ecole Polytechnique - Palaiseau | Zivny S.,University of Oxford | Zivny S.,University of Warwick
Proceedings - Annual IEEE Symposium on Foundations of Computer Science, FOCS | Year: 2012

A class of valued constraint satisfaction problems (VCSPs) is characterised by a valued constraint language, a fixed set of cost functions on a finite domain. An instance of the problem is specified by a sum of cost functions from the language with the goal to minimise the sum. This framework includes and generalises well-studied constraint satisfaction problems (CSPs) and maximum constraint satisfaction problems (Max-CSPs). Our main result is a precise algebraic characterisation of valued constraint languages whose instances can be solved exactly by the basic linear programming relaxation. Using this result, we obtain tractability of several novel and previously widely-open classes of VCSPs, including problems over valued constraint languages that are: (1) sub modular on arbitrary lattices, (2) bisubmodular (also known as k-sub modular) on arbitrary finite domains, (3) weakly (and hence strongly) tree-sub modular on arbitrary trees. © 2012 IEEE.

Warnick C.M.,University of Alberta | Warnick C.M.,University of Warwick
Communications in Mathematical Physics | Year: 2014

We consider the problem of quasinormal modes (QNM) for strongly hyperbolic systems on stationary, asymptotically anti-de Sitter black holes, with very general boundary conditions at infinity. We argue that for a time slicing regular at the horizon the QNM should be identified with certain Hk eigenvalues of the infinitesimal generator A of the solution semigroup. Using this definition we are able to prove directly that the quasinormal frequencies form a discrete, countable subset of C which in the globally stationary case accumulates only at infinity. We avoid any need for meromorphic extension, and the quasinormal modes are honest eigenfunctions of an operator on a Hilbert space. Our results apply to any of the linear fields usually considered (Klein- Gordon, Maxwell, Dirac, etc.) on a stationary black hole background, and do not rely on any separability or analyticity properties of the metric. Our methods and results largely extend to the locally stationary case. We provide a counter-example to the conjecture that quasinormal modes are complete. We relate our approach directly to the approach via meromorphic continuation. © 2014, Springer-Verlag Berlin Heidelberg.

Drummond D.R.,University of Warwick
Seminars in Cell and Developmental Biology | Year: 2011

The simple mechanistic and functional division of the kinesin family into either active translocators or non-motile microtubule depolymerases was initially appropriate but is now proving increasingly unhelpful, given evidence that several translocase kinesins can affect microtubule dynamics, whilst non-translocase kinesins can promote microtubule assembly and depolymerisation. Such multi-role kinesins act either directly on microtubule dynamics, by interaction with microtubules and tubulin, or indirectly, through the transport of other factors along the lattice to the microtubule tip. Here I review recent progress on the mechanisms and roles of these translocase kinesins. © 2011 Elsevier Ltd.

Kaverina I.,Vanderbilt University | Straube A.,University of Warwick
Seminars in Cell and Developmental Biology | Year: 2011

Microtubules define the architecture and internal organization of cells by positioning organelles and activities, as well as by supporting cell shape and mechanics. One of the major functions of microtubules is the control of polarized cell motility. In order to support the asymmetry of polarized cells, microtubules have to be organized asymmetrically themselves. Asymmetry in microtubule distribution and stability is regulated by multiple molecular factors, most of which are microtubule-associated proteins that locally control microtubule nucleation and dynamics. At the same time, the dynamic state of microtubules is key to the regulatory mechanisms by which microtubules regulate cell polarity, modulate cell adhesion and control force-production by the actin cytoskeleton. Here, we propose that even small alterations in microtubule dynamics can influence cell migration via several different microtubule-dependent pathways. We discuss regulatory factors, potential feedback mechanisms due to functional microtubule-actin crosstalk and implications for cancer cell motility. © 2011 Elsevier Ltd.

Huckstepp R.T.R.,University of California at Los Angeles | Dale N.,University of Warwick
Journal of Physiology | Year: 2011

The field of CO 2 chemosensitivity has developed considerably in recent years. There has been a mounting number of competing nuclei proposed as chemosensitive along with an ever increasing list of potential chemosensory transducing molecules. Is it really possible that all of these areas and candidate molecules are involved in the detection of chemosensory stimuli? How do we discriminate rigorously between molecules that are chemosensory transducers at the head of a physiological reflexversusthose that just happen to display sensitivity to a chemosensory stimulus? Equally, how do we differentiate between nuclei that have a primary chemosensory function,versusthose that are relays in the pathway? We have approached these questions by proposing rigorous definitions for the different components of the chemosensory reflex, going from the salient molecules and ions, through the components of transduction to the identity of chemosensitive cells and chemosensitive nuclei. Our definitions include practical and rigorous experimental tests that can be used to establish the identity of these components. We begin by describing the need for central CO 2 chemosensitivity and the problems that the field has faced. By comparing chemosensory mechanisms to those in the visual system we suggest stricter definitions for the components of the chemosensory pathway. We then, considering these definitions, re-evaluate current knowledge of chemosensory transduction, and propose the 'multiple salient signal hypothesis' as a framework for understanding the multiplicity of transduction mechanisms and brain areas seemingly involved in chemosensitivity. © 2011 The Authors. Journal compilation © 2011 The Physiological Society.

McAinsh A.D.,University of Warwick | Meraldi P.,ETH Zurich
Seminars in Cell and Developmental Biology | Year: 2011

For over 70 years, chromosomes have been known to oscillate back-and-forth on the metaphase plate. These movements are directed by kinetochores, the microtubule-attachment complexes on centromeres that regulate the dynamics of bound spindle microtubules. Recent evidence shows that the CCAN (Constitutive Centromere Associated Network) kinetochore network, which directly binds centromeric nucleosomes, plays a crucial role in the control of kinetochore microtubule dynamics. Here we review how this 15-subunit protein network functions within the kinetochore machinery, how it may adapt dynamically both in time and in space to the functional requirements necessary for controlled and faithful chromosome movements during cell division, and how this conserved protein network may have evolved in organisms with different cell division machineries. © 2011 Elsevier Ltd.

Stewart I.,University of Warwick
International Journal of Bifurcation and Chaos | Year: 2011

The multiarrow formalism for coupled cell networks permits multiple arrows and self-loops. The Lifting Theorem states that any such network is a quotient of a network in which all arrows are single and self-loops do not occur. Previous proofs are inductive, and give no useful estimate of the minimal size of the lift. We give a noninductive proof of the Lifting Theorem, and identify the number of cells in the smallest possible lift. We interpret this construction in terms of the type matrix of the network, which encodes its topology and labeling. © 2011 World Scientific Publishing Company.

Muhonen J.T.,Aalto University | Muhonen J.T.,University of Warwick | Meschke M.,Aalto University | Pekola J.P.,Aalto University
Reports on Progress in Physics | Year: 2012

A superconductor with a gap in the density of states or a quantum dot with discrete energy levels is a central building block in realizing an electronic on-chip cooler. They can work as energy filters, allowing only hot quasiparticles to tunnel out from the electrode to be cooled. This principle has been employed experimentally since the early 1990s in investigations and demonstrations of micrometre-scale coolers at sub-kelvin temperatures. In this paper, we review the basic experimental conditions in realizing the coolers and the main practical issues that are known to limit their performance. We give an update of experiments performed on cryogenic micrometre-scale coolers in the past five years. © 2012 IOP Publishing Ltd.

Hoerl C.,University of Warwick
Annals of the New York Academy of Sciences | Year: 2014

It is often thought that there is little that seems more obvious from experience than that time objectively passes, and that time is, in this respect, quite unlike space. Yet nothing in the physical picture of the world seems to correspond to the idea of such an objective passage of time. In this paper, I discuss some attempts to explain this apparent conflict between appearance and reality. I argue that existing attempts to explain the conflict as the result of a perceptual illusion fail, and that it is, in fact, the nature of memory, rather than perception, that explains why we are inclined to think of time as passing. I also offer a diagnosis as to why philosophers have sometimes been tempted to think that an objective passage of time seems to figure directly in perceptual experience, even though it does not. © 2014 The New York Academy of Sciences.

Troisi A.,University of Warwick
Organic Electronics: physics, materials, applications | Year: 2011

Elementary arguments are used to show that there is a maximum charge mobility that can be described by sequential hopping between molecules and that this maximum mobility can be expressed in terms of physical quantities that are all experimentally accessible. The evaluation of the maximum hopping mobility with realistic parameters suggests that sequential charge hopping is not the correct transport mechanism for the best molecular materials used for organic transistors. © 2011 Elsevier B.V. All rights reserved.

Kerr R.M.,University of Warwick
Journal of Fluid Mechanics | Year: 2012

Since the advent of cluster computing over 10 years ago there has been a steady output of new and better direct numerical simulation of homogeneous, isotropic turbulence with spectra and lower-order statistics converging to experiments and many phenomenological models. The next step is to directly compare these simulations to new models and new mathematics, employing the simulated data sets in novel ways, especially when experimental results do not exist or are poorly converged. For example, many of the higher-order moments predicted by the models converge slowly in experiments. The solution with a simulation is to do what an experiment cannot. The calculation and analysis of Yeung, Donzis & Sreenivasan (J. Fluid Mech., this issue, vol. 700, 2012, pp. 5-15) represents the vanguard of new simulations and new numerical analysis that will fill this gap. Where individual higher-order moments of the vorticity squared (the enstrophy) and kinetic energy dissipation might be converging slowly, they have focused upon ratios between different moments that have better convergence properties. This allows them to more fully explore the statistical distributions that eventually must be modelled. This approach is consistent with recent mathematics that focuses upon temporal intermittency rather than spatial intermittency. The principle is that when the flow is nearly singular, during bad phases, when global properties can go up and down by many orders of magnitude, if appropriate ratios are taken, convergence rates should improve. Furthermore, in future analysis it might be possible to use these ratios to gain new insights into the intermittency and regularity properties of the underlying equations. © 2012 Cambridge University Press.

Cobo I.,University of Sydney | Li M.,Tyco Fire Protection Products | Sumerlin B.S.,University of Florida | Perrier S.,University of Warwick | Perrier S.,Monash University
Nature Materials | Year: 2015

The properties and applications of biomacromolecules, for example proteins, can be enhanced by the covalent attachment of synthetic polymers. This Review discusses the modification of these biomacromolecules with stimuli-responsive polymers. © 2015 Macmillan Publishers Limited. All rights reserved.

There is great current interest in bridging the gap between robust synthetic polymers and complex biological polymers to allow for the preparation of novel functional,well-defined, biocompatible and tailorablematerials. In thismini-review recent reports on the preparation of functional amino acid polymers using controlled radical polymerisation techniques are discussed. The future potential applications of thesematerials as well as the proposed further directions in the field are also highlighted. © 2010 Society of Chemical Industry.

Woodruff D.P.,University of Warwick
Journal of Electron Spectroscopy and Related Phenomena | Year: 2010

The coherent elastic scattering by surrounding atoms of a photoelectron wave field emitted from an atomic core level provides structural information on the environment of the emitter. This basic phenomenon leads to a range of interrelated methods, the information content of which depends on the photoelectron energy and the mode of detection (angle-scan or energy-scan). A short review is presented of these methods and their application to the investigation of atomic and molecular adsorbates and epitaxial films and particles, using both laboratory-based instrumentation and synchrotron radiation. © 2009 Elsevier B.V. All rights reserved.

Allaby R.,University of Warwick
Journal of Experimental Botany | Year: 2010

Genetics has long been used as a source of evidence to understand domestication origins. A recent shift in the emphasis of archaeological evidence from a rapid transition paradigm of hunter-gatherers to agriculturalists, to a protracted transition paradigm has highlighted how the scientific framework of interpretation of genetic data was quite dependent on archaeological evidence, resulting in a period of discord in which the two evidence types appeared to support different paradigms. Further examination showed that the discriminatory power of the approaches employed in genetics was low, and framed within the rapid paradigm rather than testing it. In order to interpret genetic data under the new protracted paradigm it must be taken into account how that paradigm changes our expectations of genetic diversity. Preliminary examination suggests that a number of features that constituted key evidence in the rapid paradigm are likely to be interpreted very differently in the protracted paradigm. Specifically, in the protracted transition the mode and mechanisms involved in the evolution of the domestication syndrome have become much more influential in the shape of genetic diversity. The result is that numerous factors interacting over several levels of organization in a domestication system need to be taken into account in order to understand the evolution of the process. This presents a complex problem of integration of different data types which is difficult to describe formally. One possible way forward is to use Bayesian approximation approaches that allow complex systems to be measured in a way that does not require such formality.

Gibson M.I.,University of Warwick
Polymer Chemistry | Year: 2010

Biological antifreezes are a relatively large and diverse class of proteins (and very recently expanded to include lipopolysaccharides) which are capable of interacting with ice crystals in such a manner as to influence and, under the correct conditions, to prevent their growth. These properties allow for the survival of organisms which are either continuously or sporadically exposed to subzero temperatures which would otherwise lead to cryo-injury/death. These proteins have been found in a range of organisms, including plants, bacteria, insects and fish, and the proteins themselves have a diverse range of chemical structures ranging from the highly conserved antifreeze glycoproteins (AFGPs) to the more diverse antifreeze proteins AFPs. Their unique abilities to non-colligatively decrease the freezing point of aqueous solutions, inhibit ice recrystallisation and induce dynamic ice shaping suggest they will find many applications from cell/tissue/organ cryostorage, frozen food preservatives, texture enhancers or even as cryosurgery adjuvants. However, these applications have been limited by a lack of available material and also underlying questions regarding their mode of activity. The aim of this review article is to highlight the potential of polymeric materials to act as synthetic mimics of antifreeze(glyco) proteins, as well as to summarise the current general challenges in designing compounds capable of mimicking AF(G)Ps. This will cover the basic properties and modes of action of AF(G)Ps along with the methods commonly used to evaluate their activity. This section is essential to specifically define the 'antifreeze' terminology in terms of these proteins' unique function and to distinguish them from conventional antifreezes. A detailed evaluation of the processes involved in AF(G)P activity is beyond the scope of this review, but the reader will be pointed towards relevant literature. This will then be placed in the context of modern polymer science, with a focus on the ability of synthetic polymers to display some type of specific antifreeze activity, which will be summarised. Finally, the potential applications of these materials will be highlighted and future avenues for their research and the challenges faced in achieving these goals suggested. © 2010 The Royal Society of Chemistry.

Aigle B.,University of Lorraine | Corre C.,University of Warwick
Methods in Enzymology | Year: 2012

Streptomycete bacteria are renowned as a prolific source of natural products with diverse biological activities. Production of these metabolites is often subject to transcriptional regulation: the biosynthetic genes remain silent until the required environmental and/or physiological signals occur. Consequently, in the laboratory environment, many gene clusters that direct the biosynthesis of natural products with clinical potential are not expressed or at very low level preventing the production/detection of the associated metabolite. Genetic engineering of streptomycetes can unleash the production of many new natural products. This chapter describes the overexpression of pathway-specific activators, the genetic disruption of pathway-specific repressors, and the main strategy used to identify and characterize new natural products from these engineered Streptomyces strains. © 2012 Elsevier Inc. All rights reserved.

Woodruff D.P.,University of Warwick
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences | Year: 2015

The key ideas presented in the classic paper 'The growth of crystals and the equilibrium structure of their surfaces' by W. K. Burton, N. Cabrera and F. C. Frank, published in Philosophical Transactions A in 1951, are summarized and put in the context of both the state of knowledge at the time of publication and the considerable amount of work since that time that has built on and developed these ideas. Many of these developments exploit the huge increase in the capabilities of computer modelling that complement the original analytic approach of the paper. The dearth of relevant experimental data at the time of the original publication has been transformed by the application of increasingly sophisticated modern methods of surface science. © 2015 The Authors.

Trigkilidas D.,University of Warwick
Annals of the Royal College of Surgeons of England | Year: 2013

Knee osteoarthritis (OA) is a common and progressive joint disease. Treatment options for knee OA vary from simple analgesia in mild cases to knee replacement for advanced disease. Knee pain due to moderate OA can be targeted with intra-articular injections. Steroid injections have been used widely in managing acute flare-ups of the disease. In recent years, viscosupplementation has been used as a therapeutic modality for the management of knee OA. The principle of viscosupplementation is based on the physiological properties of the hyaluronic acid (HA) in the synovial joint. Despite a sound principle and promising in vitro studies, clinical studies have been less conclusive on the effectiveness of HA in managing osteoarthritic knee pain. The aim of this systematic review was to assess the effectiveness of HA intra-articular injections in the management of osteoarthritic knee pain. A systematic review of the literature was performed using MEDLINE®, Embase™ and CINAHL® (Cumulative Index to Nursing and Allied Health Literature). The databases were searched for randomised controlled trials available on the effectiveness of HA intra-articular injections in managing osteoarthritic knee pain. The search yielded 188 studies. Of these, 14 met the eligibility criteria and were reviewed in chronological order. HA intra-articular injections have a modest effect on early to moderate knee OA. The effect peaks at around 6-8 weeks following administration, with a doubtful effect at 6 months.

Birchwood M.,University of Birmingham | Singh S.P.,Youthspace | Singh S.P.,University of Warwick
British Journal of Psychiatry | Year: 2013

It is now known that the onset of severe and recurring mental health problems begins for the most part before the age of 25: this provides a clear focus for preventive strategies and public mental health that are a feature of many health policy frameworks. The present distinction between child and adolescent mental health services and adult services at 16 or 18 does not fit easily with these data and the now well-documented problems of transition suggest that a fundamental review of services for young people is overdue. This supplement provides an overview of the epidemiological, conceptual and service structures for young people with emergent and existing mental health problems, and asks the question, 'How should we design services for young people to promote prevention and service engagement, and to improve outcomes?'.

Maric M.,University of Dundee | Maric M.,University of Manchester | Maculins T.,University of Manchester | Maculins T.,Astrazeneca | And 3 more authors.
Science | Year: 2014

Chromosome replication is initiated by a universal mechanism in eukaryotic cells, involving the assembly and activation at replication origins of the CMG (Cdc45-MCM-GINS) DNA helicase, which is essential for the progression of replication forks. Disassembly of CMG is likely to be a key regulated step at the end of chromosome replication, but the mechanism was unknown until now. Here we show that the ubiquitin ligase known as SCFDia2 promotes ubiquitylation of CMG during the final stages of chromosome replication in Saccharomyces cerevisiae. The Cdc48/p97 segregase then associates with ubiquitylated CMG, leading rapidly to helicase disassembly. These findings indicate that the end of chromosome replication in eukaryotes is controlled in a similarly complex fashion to the much-better-characterized initiation step. © 2014, American Association for the Advancement of Science. All rights reserved.

Johnson S.,University of Leicester | Wolke D.,University of Warwick
Early Human Development | Year: 2013

Preterm birth is associated with a high risk of residual neurodevelopmental disability and cognitive impairment. These problems are closely associated with psychiatric disorders and thus it is unsurprising that preterm birth also confers high risk for poor long term mental health. The risk associated with preterm birth is not a general one, but appears to be specific to symptoms and disorders associated with anxiety, inattention and social and communication problems, and manifest in a significantly higher prevalence of emotional disorders, ADHD and Autism. Adolescence is a key period for mental health and studies have shown that problems evident in childhood persist over this time and are more stable amongst preterm individuals than term-born peers. There is also modest evidence for an increased prevalence of psychotic symptoms in preterm adolescents. The high prevalence of psychiatric disorders, present in around 25% of preterm adolescents, requires long term screening and intervention. © 2013 Elsevier Ltd.

Noble R.,University of Warwick
Australasian Plant Pathology | Year: 2011

The supply of composts has increased in many countries due to the enforced diversion from landfill of organic biodegradable wastes. Disposal is often the primary financial and environmental incentive for composting this organic waste, with benefits from low value end-products such as organic soil amendments being a secondary or negligible consideration. The use of composts can also pose risks from populations of plant and animal pathogens which may have survived the composting process. However, the suppressive effect of amending soils with composts on crop and turf grass diseases caused by soil-borne plant pathogens can be a significant benefit. The increasing environmental unacceptability and unavailability of effective chemical fungicide treatments has increased this potential value of composts. Information on the effects of compost amendment of soil or sand on diseases caused by soil-borne pathogens was reviewed. Out of 79 container experiments, where soil was generally amended with≥20 %v/v compost, 59 showed a disease suppressive effect and only 6 showed a disease promoting effect of the compost amendment. Following amendment of soil in the field with compost, generally at≥15 t/ha, disease suppression occurred in 45 out of 59 experiments, and disease promotion in only one. Although abiotic factors such as increases in soil pH or release of volatiles following compost amendment explained control of some diseases, loss of suppressiveness following compost sterilisation frequently demonstrated a biological control mechanism such as microbial antagonism or induced plant resistance. Prediction of the disease suppressiveness of composts or compost amended soils from their microbial activity by measurement of the hydrolysis of fluorescein diacaetate, dehydrogenase activity, or basal respiration has been variable. Changes in microbial community structure detected using T-RFLP and DGGE analyses have been more reliable indicators of the disease suppressiveness of compost amended soils. Inoculation of composts with biological control agents is also a promising technique for improving the efficacy and reliability of disease suppression following soil amendment. © 2010 Australasian Plant Pathology Society Inc.

Salassa L.,University of Warwick
European Journal of Inorganic Chemistry | Year: 2011

Polypyridyl metal complexes have optical properties that have been exploited in a wide range of biological and technological applications. Their structural diversity, chemical and redox properties provide a unique opportunity for designing new anticancer agents. Despite this great potential, relatively little is known about the cytotoxic effects of metal polypyridyl complexes, at least in comparison with other classes of coordination and organometallic compounds. This review uses selected examples to illustrate the most recent research carried out on this class of complexes as enzyme inhibitors and cytotoxic agents. Metal polypyridyl complexes are widely studied in coordination chemistry and have been employed in a wide range of applications, from catalysis to chemical biology. However, their use as potential anticancer agents has not been fully explored. This review highlights recent examples of metal polypyridyl complexes studied for their enzyme-inhibition and cytotoxicity properties. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

King P.D.C.,University of St. Andrews | Veal T.D.,University of Warwick
Journal of Physics Condensed Matter | Year: 2011

Despite an extensive research effort for over 60 years, an understanding of the origins of conductivity in wide band gap transparent conducting oxide (TCO) semiconductors remains elusive. While TCOs have already found widespread use in device applications requiring a transparent contact, there are currently enormous efforts to (i)increase the conductivity of existing materials, (ii)identify suitable alternatives, and (iii)attempt to gain semiconductor-engineering levels of control over their carrier density, essential for the incorporation of TCOs into a new generation of multifunctional transparent electronic devices. These efforts, however, are dependent on a microscopic identification of the defects and impurities leading to the high unintentional carrier densities present in these materials. Here, we review recent developments towards such an understanding. While oxygen vacancies are commonly assumed to be the source of the conductivity, there is increasing evidence that this is not a sufficient mechanism to explain the total measured carrier concentrations. In fact, many studies suggest that oxygen vacancies are deep, rather than shallow, donors, and their abundance in as-grown material is also debated. We discuss other potential contributions to the conductivity in TCOs, including other native defects, their complexes, and in particular hydrogen impurities. Convincing theoretical and experimental evidence is presented for the donor nature of hydrogen across a range of TCO materials, and while its stability and the role of interstitial versus substitutional species are still somewhat open questions, it is one of the leading contenders for yielding unintentional conductivity in TCOs. We also review recent work indicating that the surfaces of TCOs can support very high carrier densities, opposite to the case for conventional semiconductors. In thin-film materials/devices and, in particular, nanostructures, the surface can have a large impact on the total conductivity in TCOs. We discuss models that attempt to explain both the bulk and surface conductivity on the basis of bulk band structure features common across the TCOs, and compare these materials to other semiconductors. Finally, we briefly consider transparency in these materials, and its interplay with conductivity. Understanding this interplay, as well as the microscopic contenders for providing the conductivity of these materials, will prove essential to the future design and control of TCO semiconductors, and their implementation into novel multifunctional devices. © 2001 IOP Publishing Ltd.

Zhao C.Y.,Shanghai JiaoTong University | Zhang G.H.,University of Warwick
Renewable and Sustainable Energy Reviews | Year: 2011

The use of latent heat storage, microencapsulated phase change materials (MEPCMs), is one of the most efficient ways of storing thermal energy and it has received a growing attention in the past decade. However, there is no complete overview of its utilization in thermal energy storage systems, and the information is widely spread in the literature. In this paper, a comprehensive review has been carried out for MEPCMs. Four aspects have been the focus of this review: fabrication and characterization of MEPCMs, applications of MEPCMs to the textile and building, fundamental properties of microencapsulated phase change material slurry (MPCS) and application of MPCS to the thermal energy storage system. Over 140 recent publications are referenced in this paper. © 2011 Elsevier Ltd. All rights reserved.

Du J.,Tongji University | O'Reilly R.K.,University of Warwick
Chemical Society Reviews | Year: 2011

Anisotropic particles, such as patchy, multicompartment and Janus particles, have attracted significant attention in recent years due to their novel morphologies and diverse potential applications. The non-centrosymmetric features of these particles make them a unique class of nano- or micro-colloidal materials. Patchy particles usually have different compositional patches in the corona, whereas multicompartment particles have a multi-phasic anisotropic architecture in the core domain. In contrast, Janus particles, named after the double-faced Roman god, have a strictly biphasic geometry of distinct compositions and properties in the core and/or corona. The term Janus particles, multicompartment particles and patchy particles frequently appears in the literature, however, they are sometimes misused due to their structural similarity. Therefore, in this critical review we classify the key features of these different anisotropic colloidal particles and compare structural properties as well as discuss their preparation and application. This review brings together and highlights the significant advances in the last 2 to 3 years in the fabrication and application of these novel patchy, multicompartment and Janus particles (98 references). © 2011 The Royal Society of Chemistry.

House T.,University of Warwick
Bulletin of Mathematical Biology | Year: 2015

Moment closure on general discrete structures often requires one of the following: (i) an absence of short-closed loops (zero clustering); (ii) existence of a spatial scale; (iii) ad hoc assumptions. Algebraic methods are presented to avoid the use of such assumptions for populations based on clumps and are applied to both SIR and macroparasite disease dynamics. One approach involves a series of approximations that can be derived systematically, and another is exact and based on Lie algebraic methods. © 2014, Society for Mathematical Biology.

Tian Y.,University of Warwick | Zhao C.Y.,Shanghai JiaoTong University
International Journal of Heat and Mass Transfer | Year: 2013

Metal Foam-enhanced Cascaded Thermal Energy Storage (MF-CTES) has been proposed to solve the problem of poor heat transfer during heat exchange process, which is caused by unavoidable decrease of temperature differences. This paper conducts a theoretical study examining the overall thermal performance of Single-stage Thermal Energy Storage (STES), Cascaded Thermal Energy Storage (CTES) and MF-CTES, with both heat exchange rate and exergy efficiency being considered. The main findings are: heat exchange rate of STES is improved by CTES (up to 30%), and is further improved by MF-CTES (by 2-7 times); exergy efficiency of STES cannot be significantly improved by CTES (-15% to +30%), nor by MF-CTES; exergy transfer rate of STES is increased by CTES (up to 23%), and is further increased by MF-CTES (by 2-7 times). © 2012 Elsevier Ltd. All rights reserved.

Henfridsson O.,University of Warwick | Lind M.,Viktoria Institute
Journal of Strategic Information Systems | Year: 2014

The realized strategy contents of information systems (IS) strategizing are a result of both deliberate and emergent patterns of action. In this paper, we focus on emergent patterns of action by studying the formation of strategies that build on local technology-mediated practices. This is done through case study research of the emergence of a sustainability strategy at a European automaker. Studying the practices of four organizational sub-communities, we develop a process perspective of sub-communities' activity-based production of strategy contents. The process model explains the contextual conditions that make sub-communities initiate SI strategy contents production, the activity-based process of strategy contents production, and the IS strategy outcome. The process model, which draws on Jarzabkowski's strategy-as-practice lens and Mintzberg's strategy typology, contributes to the growing IS strategizing literature that examines local practices in IS efforts of strategic importance.© 2013 Elsevier B.V. All rights reserved.

Lewis W.J.,University of Warwick
Journal of Architectural Engineering | Year: 2013

Fabric structures demonstrate an enormous application potential of tensioned fabric as a medium for creating dramatic looking, free-form architectural enclosures. However, their design presents a number of challenges. First, their shape cannot be known accurately at the outset; it must be found through a process of form-finding. Second, under imposed loading (wind or snow), they exhibit a visible form-force interaction, which must be taken into account at the load analysis stage. Finally, the manufacture of a three-dimensional fabric surface must involve a patterning stage, which maps the surface onto a series of two-dimensional panels cut in unstrained fabric. As discussed in this paper, all of the design stages require specialist computational modeling based on good understanding of the relationship between form and stress. Much of the discussion in the paper centers on misconceptions associated with form-finding, as well as the inadequacies of some computational approaches to form-finding and patterning. The question of what constitutes an optimal form points to the use of natural principles in the conceptual design of fabric structures. © 2013 American Society of Civil Engineers.

Troisi A.,University of Warwick
Chemical Society Reviews | Year: 2011

The theories developed since the fifties to describe charge transport in molecular crystals proved to be inadequate for the most promising classes of high mobility molecular semiconductors identified in the recent years, including for example pentacene and rubrene. After reviewing at an elementary level the classical theories, which still provide the language for the understanding of charge transport in these systems, this tutorial review outlines the recent experimental and computational evidence that prompted the development of new theories of charge transport in molecular crystals. A critical discussion will illustrate how very rarely it is possible to assume a charge hopping mechanism for high mobility organic crystals at any temperature. Recent models based on the effect of non-local electron-phonon coupling, dynamic disorder, coexistence of localized and delocalized states are reviewed. Additionally, a few more recent avenues of theoretical investigation, including the study of defect states, are discussed. © 2011 The Royal Society of Chemistry.

Zhang Y.,University of Warwick
International Communications in Heat and Mass Transfer | Year: 2013

Heat transfer across interfaces of oscillating gas bubbles in liquids is a fundamental issue of bubble dynamics with many applications. The current formulas in the literature relating with heat transfer are either too complex to be used for calculation or not valid for some regions of interest. In this communication, a group of formulas is proposed to predict heat transfer across bubble interfaces accurately for a wide range of parameters. An exact solution is used to validate the accuracy of the present formulas. Finally, energy dissipation during gas bubble oscillations in liquids through heat transfer is quantitatively compared with those through viscosity and acoustic radiation. © 2013 Elsevier Ltd.

Bhatia S.,University of Warwick
Psychonomic Bulletin and Review | Year: 2014

The common-ratio, common-consequence, reflection, and event-splitting effects are some of the best-known findings in decision-making research. They represent robust violations of expected utility theory, and together form a benchmark against which descriptive theories of risky choice are tested. These effects are not currently predicted by sequential sampling models of risky choice, such as decision field theory (Busemeyer & Townsend 1993). This paper, however, shows that a minor extension to decision field theory, which allows for stochastic error in event sampling, can provide a parsimonious, cognitively plausible explanation for these effects. Moreover, these effects are guaranteed to emerge for a large range of parameter values, including best-fit parameters obtained from preexisting choice data. © 2014, Psychonomic Society, Inc.

Lewandowski J.R.,University of Warwick
Accounts of Chemical Research | Year: 2013

Dynamics are intimately linked to protein stability and play a crucial role in important biological processes, such as ligand binding, allosteric regulation, protein folding, signaling, and enzymatic catalysis. Solid-state NMR relaxation measurements allow researchers to determine the amplitudes, time scales, and under favorable conditions, directionality of motions at atomic resolution over the entire range of dynamic processes from picoseconds to milliseconds. Because this method allows researchers to examine both the amplitudes and time scales of motions in this range, they can link different tiers of protein motions in protein energy landscapes. As a result, scientists can better understand the relationships between protein motions and functions. Such studies are possible both with the primary targets of solid-state NMR studies, such as amyloid fibrils, membrane proteins, or other heterogeneous systems, and others that researchers typically study by solution NMR and X-ray crystallography. In addition, solid-state NMR, with the absence of tumbling in solution, eliminates the intrinsic size limitation imposed by slow tumbling of large proteins. Thus, this technique allows researchers to characterize interdomain and intermolecular interactions in large complexes at the atomic scale.In this Account, we discuss recent advances in solid-state relaxation methodology for studying widespread site-specific protein dynamics. We focus on applications involving magic angle spinning, one of the primary methods used in high-resolution solid-state NMR. We give an overview of challenges and solutions for measuring 15N and 13C spin-lattice relaxation (R 1) to characterize fast picosecond-nanosecond motions, spin-lattice in the rotating frame (R1ρ), and other related relaxation rates for characterization of picosecond-millisecond protein motions. In particular, we discuss the problem of separating incoherent effects caused by random motions from coherent effects arising from incomplete averaging of orientation- dependent NMR interactions. We mention a number of quantitative studies of protein dynamics based on solid-state relaxation measurements. Finally, we discuss the potential use of relaxation measurements for extracting the directionality of motions. Using the 15N and 13C R 1 and R1ρ measurements, we illustrate the backbone and side-chain dynamics in the protein GB1 and comment on this emerging dynamic picture within the context of data from solution NMR measurements and simulations. © 2013 American Chemical Society.

Zhang Y.,University of Warwick
Journal of Fluids Engineering, Transactions of the ASME | Year: 2013

When irradiated by acoustic waves, gas bubbles can generate divergent spherical waves, which are frequently used to detect the sizes and number density of the gas bubbles. In this paper, a generalized equation for scattering cross section of spherical gas bubbles oscillating in liquids under acoustic excitation is proposed. Comparing with formulas in the literature, this generalized equation can improve the predictions of acoustical scattering cross section in the near-resonance region with high ambient pressure and above-resonance region. © 2013 by ASME.

Pace M.F.,University of Warwick
Procedia Computer Science | Year: 2012

The MapReduce framework has been generating a lot of interest in a wide range of areas. It has been widely adopted in industry and has been used to solve a number of non-trivial problems in academia. Putting MapReduce on strong theoretical foundations is crucial in understanding its capabilities. This work links MapReduce to the BSP model of computation, underlining the relevance of BSP to modern parallel algorithm design and defining a subclass of BSP algorithms that can be efficiently implemented in MapReduce. © 2012 Published by Elsevier Ltd.

Rawnsley J.,University of Warwick
Journal of Geometry and Physics | Year: 2012

A model for the universal covering group of the symplectic group as a Lie group, and some calculations based on the model, as well as defining a similar model for the Lagrangian Grassmannian and relating our construction to the Maslov Index. © 2012 Elsevier B.V.

Hooper J.M.,Millbrook Proving Ground | Marco J.,University of Warwick
Journal of Power Sources | Year: 2014

There has been little published research critically examining the mechanical integration of battery systems within either EVs or HEVs. Many of the existing Standards are designed to validate the fail safe function of the battery pack as opposed to assessing the mechanical durability of the complete system. If excessive vehicle warranty claims are to be avoided it is important that engineers tasked with the design of the battery installation properly understand the magnitude and frequency of the vibration inputs that the battery will be exposed too during the vehicle's predicted life. The vibration characteristics of three different commercially available EVs have been experimentally evaluated over a wide range of different road surface conditions. For each vehicle, a durability profile has been sequenced to emulate the vibration energy that the battery pack may be exposed too during a representative 100,000 miles service life. The primary conclusions from the results presented are that the battery packs may well be exposed to vibration loads outside the current evaluation range of existing Standards. © 2013 Elsevier B.V. All rights reserved.

Chen Y.,University of Warwick
IEEE Transactions on Wireless Communications | Year: 2016

Energy-harvesting relaying is a promising solution to the extra energy requirement at the relay. It can transfer energy from the source to the relay. This will encourage more idle nodes to be involved in relaying. In this paper, the outage probability and the throughput of an amplify-and-forward relaying system using energy harvesting are analyzed. Both time switching and power-splitting harvesting schemes are considered. The analysis takes into account both the Nakagami-m fading caused by signal propagation and the interference caused by other transmitters. Numerical results show that time switching is more sensitive to system parameters than power splitting. Also, the system performance is more sensitive to the transmission rate requirement, the signal-to-interference-plus-noise ratio in the first hop and the relaying method. © 2002-2012 IEEE.

Troisi A.,University of Warwick
Faraday Discussions | Year: 2013

We introduced a minimal model of the donor-acceptor interface encountered in organic solar cells to explain the efficient generation of free charges in these systems and we investigated the nature of charge transfer states formed by a delocalized exciton in the donor component. Contrarily to the generally accepted view excitons do not generate strongly bound hole-electron pairs, but relatively delocalized charge transfer states with energy very close to the energy of free holes and electrons. These states are kinetically more accessible from the exciton state and very close in structure to the free hole and electron states. The most relevant molecular parameter that affects the rate of exciton dissociation is the electronic coupling between donor orbitals and acceptor orbitals, i.e. the band widths of the donor and acceptor materials. Moreover, and to some surprise, we find that the process of charge separation is mostly a purely electronic process and a very similar physics can be described neglecting the role of nuclear degrees of freedom altogether. © 2013 The Royal Society of Chemistry.

Currie G.,University of Warwick
Journal of health services research & policy | Year: 2013

There exists a translation gap between academic research and clinical practice in health care systems. One policy-driven initiative to address the translation gap in England are the Collaborations for Leadership in Applied Health Research and Care (CLAHRCs), funded by the National Institute of Health Research (NIHR). These aim to bring together NHS organizations and universities to accelerate the translation of evidence-based innovation into clinical practice. Our aim was to draw out lessons for policy-makers regarding the mobilization of such initiatives. Qualitative semi-structured interviews with 174 participants across nine CLAHRCs plus in-depth case studies across four CLAHRCs. Those interviewed were staff who were central to the CLAHRCs including senior managers and directors, junior and senior academics, and health care practitioners. Social positions of the CLAHRC leaders, conceived as institutional entrepreneurs, together with the antecedent conditions for CLAHRC bids, had an impact on the vision for a CLAHRC. The process of envisioning encompassed diagnostic and prognostic framing. Within the envisioning process, the utilization of existing activities and established relationships in the CLAHRC bid influenced early mobilization. However, in some cases, it led to a translational 'lock in' towards established models regarding applied research. The CLAHRC experiment in England holds important lessons for policy-makers regarding how to address the translation gap. First, policy makers need to consider whether they set out a defined template for translational initiatives or whether variation is encouraged. We might expect a degree of learning from pilot activities within a CLAHRC that allows for greater clarity in the design of subsequent translational initiatives. Second, policy makers and practitioners need to understand the importance of both antecedent conditions and the social position of senior members of a CLAHRC (institutional entrepreneurs) leading the development of a bid. Whilst established and well-known clinical academics are likely to be trusted to lead CLAHRCs, and the presence of pre-existing organizational relationships are important for mobilization, privileging these aspects may constrain more radical change.

Allaby R.G.,University of Warwick
Genome Biology | Year: 2015

Genomic analysis of barley paints a picture of diffuse origins of this crop, with different regional wild populations contributing putative adaptive variations. © 2015 Allaby.

Nguyen T.T.,Liverpool John Moores University | Yang S.,Brunel University | Branke J.,University of Warwick
Swarm and Evolutionary Computation | Year: 2012

Optimization in dynamic environments is a challenging but important task since many real-world optimization problems are changing over time. Evolutionary computation and swarm intelligence are good tools to address optimization problems in dynamic environments due to their inspiration from natural self-organized systems and biological evolution, which have always been subject to changing environments. Evolutionary optimization in dynamic environments, or evolutionary dynamic optimization (EDO), has attracted a lot of research effort during the last 20 years, and has become one of the most active research areas in the field of evolutionary computation. In this paper we carry out an in-depth survey of the state-of-the-art of academic research in the field of EDO and other meta-heuristics in four areas: benchmark problems/generators, performance measures, algorithmic approaches, and theoretical studies. The purpose is to for the first time (i) provide detailed explanations of how current approaches work; (ii) review the strengths and weaknesses of each approach; (iii) discuss the current assumptions and coverage of existing EDO research; and (iv) identify current gaps, challenges and opportunities in EDO. © 2012 Elsevier B.V. All rights reserved.

Cunliffe M.,Marine Biological Association of The United Kingdom | Upstill-Goddard R.C.,Northumbria University | Murrell J.C.,University of Warwick
FEMS Microbiology Reviews | Year: 2011

Aquatic surface microlayers are unique microbial ecosystems found at the air-water interface of all open water bodies and are often referred to as the neuston. Unambiguous interpretation of the microbiology of aquatic surface microlayers relies on robust sampling, for which several methods are available. All have particular advantages and disadvantages that make them more or less suited to this task. A key feature of surface microlayers is their role in regulating air-water gas exchange, which affords them a central role in global biogeochemistry that is only now being fully appreciated. The microbial populations in surface microlayers can impact air-water gas exchange through specific biogeochemical processes mediated by particular microbial groups such as methanotrophs or through more general metabolic activity such as the balance of primary production vs. heterotrophy. There have been relatively few studies of surface microlayers that have utilized molecular ecology techniques. The emerging consensus view is that aquatic surface microlayers are aggregate-enriched biofilm environments containing complex microbial communities that are ecologically distinct from those present in the subsurface water immediately below. Future research should focus on unravelling the complex interactions between microbial diversity and the ecosystem function of surface microlayers in order to better understand the important but complex role of microorganisms in Earth system processes. © 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Monti S.,CNR Institute of Chemistry of organometallic Compounds | Walsh T.R.,University of Warwick
Journal of Physical Chemistry C | Year: 2010

The potential of mean constraint force approach, in partnership with atomistic molecular dynamics simulations, is used to calculate the change in free energy upon adsorption of amino acid side chain analogues at the aqueous rutile titania (110) interface. Our results indicate that both positively charged and negatively charged moieties have favorable free energy of binding to the titania surface. Stable contact, mediated via the first two solvent layers at the interface, is also indicated for the charged adsorbates. Hydrophobic adsorbates showed no appreciable binding to the titania surface. In contrast, the binding for our serine analogue (methanol) features a slight possibility to bind via hydrogen bonding to the titania surface. Our calculated results indicate very good agreement with available experimental data. In partnership with other information regarding peptide conformation and intrapeptide interactions, our findings should be helpful in building design principles for peptide sequences with predictable and controllable binding to titania. © 2010 American Chemical Society.

Livanos I.,University of Warwick
Regional Studies | Year: 2010

Livanos I. The wage-local unemployment relationship in a highly regulated labour market: Greece, Regional Studies. Using data obtained from 80 000 employees, this paper examines the relationship between individual wages and regional unemployment in Greece. The findings highlight the dynamics of the local labour markets in a case such as Greece, where the Organisation for Economic Co-operation and Development (OECD) claims that wage flexibility is limited. This study does not find evidence that wages in Greece are rigid, but finds a wage curve elasticity of close to -0.1, which corresponds to evidence from many counties. Interestingly, graduates are found to be the most responsive group of workers to the behaviour of local labour markets. © 2010 Regional Studies Association.

Stone D.,University of Warwick
Policy and politics | Year: 2010

The Open Society Institute (OSI) is a private operating and grant-making foundation that serves as the hub of the Soros Foundations Network, a group of autonomous national foundations around the world. OSI is a mechanism for the international diffusion of expertise and 'best practices' to post-communist countries and other democratising nations. Focusing on the 'soft' ideational and normative policy transfer, the article highlights the engagement in governance that comes with OSI transnational policy partnerships. © The Policy Press, 2010.

Williams K.P.,Sandia National Laboratories | Kelly D.P.,University of Warwick
International Journal of Systematic and Evolutionary Microbiology | Year: 2013

The order Acidithiobacillales was previously assigned to the class Gammaproteobacteria. Recent analyses have indicated that this order actually lies outside all the proteobacterial classes, as a sister group to the combined classes Betaproteobacteria and Gammaproteobacteria. We now confirm this result with multiprotein phylogenetic analysis of all the available genomes of members of the order Acidithiobacillales and representatives of all available bacterial orders, and propose the new proteobacterial class, Acidithiobacillia, with the type order Acidithiobacillales, comprising the families Acidithiobacillaceae and Thermithiobacillaceae with the type genus Acidithiobacillus. © 2013 IUMS.

Richardson B.,University of Warwick
Environment and Planning C: Government and Policy | Year: 2012

Industrial biotechnology involves the replacement of petrochemical processes and inputs with more energy-efficient and renewable biological ones. It is already being used in the production of biofuels and bioplastics and has been touted as a means by which modern economies can be shifted toward a more competitive, low-carbon growth model. This paper does two things. First, it outlines the policy framework established in the European Union and the narrative of a knowledge-based bioeconomy (KBBE) underpinning this. Second, it argues that the 'win-win' rhetoric contained within the KBBE narrative is misleading. Among the different groups commenting on the use of industrial biotechnology, the paper locates cleavages between farmers and agribusiness, between those convinced and those sceptical of environmental technofixes, and between procorporate and anti-corporate NGOs. Taken together, they show the purported transition from a fossil-fuel to a bio-based economy to be a resolutely political one. © 2012 Pion Ltd and its Licensors.

Woodland H.R.,University of Warwick
Current Topics in Developmental Biology | Year: 2015

The evolution of multicellular animals has been attributed to many kinds of selective advantage; here I suggest that the evolution of somatic cells to feed and protect the germline was central to the appearance of animals. This would have been driven by selection for extreme anisogamy-the evolution of sperm and egg. Evidence is adduced from the germline stem cells of simple animals (defining germline as any cell that normally produces the next generation via the sexual process) and from the control circuitry ubiquitous in animal germlines. With the soma and its elaboration came animal development, as we understand it. © 2016 Elsevier Inc.

House T.,University of Warwick
Contemporary Physics | Year: 2012

Infectious disease remains, despite centuries of work to control and mitigate its effects, a major problem facing humanity. This paper reviews the mathematical modelling of infectious disease epidemics on networks, starting from the simplest Erdös-Rényi random graphs, and building up structure in the form of correlations, heterogeneity and preference, paying particular attention to the links between random graph theory, percolation and dynamical systems representing transmission. Finally, the problems posed by networks with a large number of short closed loops are discussed. © 2012 Copyright Taylor and Francis Group, LLC.

Davies J.S.,University of Warwick
Policy and politics | Year: 2012

This article develops a distinct perspective on the continuities and contrasts between Thatcherite Conservatism and New Labour, interpreted through active citizenship policy. Revisiting Thatcherism, it argues that the roots of the New Labour approach to active citizenship can be traced to the late-Thatcher period. It explores six facets of New Labour's agenda, arguing in each case that there were affinities with Conservatism. These affinities further highlight continuities in the 'social dimension' of an ongoing hegemonic project, whose objective is to overcome the 'weak citizenship' characteristic of neoliberalism by mobilising citizen assent. Judged against this benchmark, the project may have had only limited success. © The Policy Press, 2012.

Hodges S.,University of Warwick
Social History of Medicine | Year: 2012

The history of medicine has gone 'global.' Why? Can the proliferation of the 'global' in our writing be explained away as a product of staying true to our historical subjects' categories? Or has this historiography in fact delivered a new 'global' problematic or performed serious 'global' analytic work? The situation is far from clear, and it is the tension between the global as descriptor and an analytics of the global that concerns me here. I have three main concerns: (1) that there is an epistemic collusion between the discourses of universality that inform medical science and global-talk; (2) that the embrace of the 'global' authorises a turning away from analyses of power in history-writing in that (3) this turning away from analyses of power in history-writing leads to scholarship that reproduces rather than critiques globalisation as a set of institutions, discourses and practices. © 2012 The Author.

Laurie J.,Ecole Normale Superieure de Lyon | Bortolozzo U.,University of Nice Sophia Antipolis | Nazarenko S.,University of Warwick | Residori S.,University of Nice Sophia Antipolis
Physics Reports | Year: 2012

We present a review of the latest developments in one-dimensional (1D) optical wave turbulence (OWT). Based on an original experimental setup that allows for the implementation of 1D OWT, we are able to show that an inverse cascade occurs through the spontaneous evolution of the nonlinear field up to the point when modulational instability leads to soliton formation. After solitons are formed, further interaction of the solitons among themselves and with incoherent waves leads to a final condensate state dominated by a single strong soliton. Motivated by the observations, we develop a theoretical description, showing that the inverse cascade develops through six-wave interaction, and that this is the basic mechanism of nonlinear wave coupling for 1D OWT. We describe theory, numerics and experimental observations while trying to incorporate all the different aspects into a consistent context. The experimental system is described by two coupled nonlinear equations, which we explore within two wave limits allowing for the expression of the evolution of the complex amplitude in a single dynamical equation. The long-wave limit corresponds to waves with wave numbers smaller than the electrical coherence length of the liquid crystal, and the opposite limit, when wave numbers are larger. We show that both of these systems are of a dual cascade type, analogous to two-dimensional (2D) turbulence, which can be described by wave turbulence (WT) theory, and conclude that the cascades are induced by a six-wave resonant interaction process. WT theory predicts several stationary solutions (non-equilibrium and thermodynamic) to both the long- and short-wave systems, and we investigate the necessary conditions required for their realization. Interestingly, the long-wave system is close to the integrable 1D nonlinear Schrödinger equation (NLSE) (which contains exact nonlinear soliton solutions), and as a result during the inverse cascade, nonlinearity of the system at low wave numbers becomes strong. Subsequently, due to the focusing nature of the nonlinearity, this leads to modulational instability (MI) of the condensate and the formation of solitons. Finally, with the aid of the probability density function (PDF) description of WT theory, we explain the coexistence and mutual interactions between solitons and the weakly nonlinear random wave background in the form of a wave turbulence life cycle (WTLC). © 2012 Elsevier B.V.

This article critically assesses literature on militarized landscapes (sites that are partially or fully mobilized to achieve military aims). It argues that alongside increasing public and media attention, militarized landscapes are a burgeoning area of inquiry in a variety of disciplines, including geography, history, earth sciences and archaeology. To allow for an analysis of different disciplinary perspectives around common themes, this article is structured around the areas of preparing for war, the battlefield, and the 'homefront'. In light of the research identified in this article, it is no longer possible to treat war and landscape as separate realms. Instead, the challenge is to explore how war and landscapes reciprocally reproduce each other across time and space. The common themes that exist across the scholarly disciplines also indicate the potential for extensive interdisciplinary research into militarized landscapes. © 2012 Copyright Taylor and Francis Group, LLC.

Boyce C.J.,Ecole Normale Superieure de Paris | Oswald A.J.,University of Warwick
Health Economics | Year: 2012

This paper examines the hypothesis that greater job status makes a person healthier. It begins by successfully replicating the well-known cross-section association between health and job seniority. Then, however, it turns to longitudinal patterns. Worryingly for the hypothesis, the data - on a large sample of randomly selected British workers through time - suggest that people who start with good health go on later to be promoted. The paper can find relatively little evidence that health improves after promotion. In fact, promoted individuals suffer a significant deterioration in their psychological well-being (on a standard General Health Questionnaire (GHQ) mental ill-health measure). Copyright © 2011 John Wiley & Sons, Ltd.

Loomes G.,University of Warwick
Psychological Review | Year: 2010

This article develops a parsimonious descriptive model of individual choice and valuation in the kinds of experiments that constitute a substantial part of the literature relating to decision making under risk and uncertainty. It suggests that many of the best known " regularities" observed in those experiments may arise from a tendency for participants to perceive probabilities and payoffs in a particular way. This model organizes more of the data than any other extant model and generates a number of novel testable implications which are examined with new data. © 2010 American Psychological Association.

Stallard N.,University of Warwick
Statistics in Medicine | Year: 2010

Seamless phase II/III designs allow strong control of the familywise type I error rate when the most promising of a number of experimental treatments is selected at an interim analysis to continue along with the control treatment. If the primary endpoint is observed only after long-term follow-up it may be desirable to use correlated short-term endpoint data available at the interim analysis to inform the treatment selection. If short-term data are available for some patients for whom the primary endpoint is not available, basing treatment selection on these data may, however, lead to inflation of the type I error rate. This paper proposes a method for the adjustment of the usual group-sequential boundaries to maintain strong control of the familywise error rate even when short-term endpoint data are used for the treatment selection at the first interim analysis. This method allows the use of the short-term data, leading to an increase in power when these data are correlated with the primary endpoint data. Copyright © 2010 John Wiley & Sons, Ltd.

York S.,University of Warwick
Social History of Medicine | Year: 2012

Suicidal lunatics were only one patient group among several that alienists and asylum attendants had to care for, but the danger and risk associated with suicide made them one of the more difficult to manage. The task of suicide prevention was a priority for asylum staff as they endeavoured to save life and avoid criticism and investigation from the asylums' regulating body. This article investigates the contribution alienists and attendants made to the management and prevention of suicide in English public lunatic asylums during the second half of the nineteenth century. It examines the respective contribution alienists and attendants made to the handling of suicidal patients, with varying levels of involvement. In doing so, it argues that the practical application of suicide prevention fell to asylum attendants, as their work determined how, and with what success, alienists' suicide policy was implemented. © The 2011 Author.

Yin X.,China University of Petroleum - East China | Hutchins D.A.,University of Warwick
Composites Part B: Engineering | Year: 2012

This paper describes the application of the capacitive imaging technique to the inspection of composite materials. The fundamental theory of the capacitive imaging technique was briefly described. Experiments using prototype capacitive imaging probes were also carried out. The proof-of-concept results indicated that the capacitive imaging technique could be used to detect cracks and delaminations in the glass fibre composite, defects in the aluminium core through the glass fibre face as well as surface features on the carbon fibre specimens. © 2011 Elsevier Ltd. All rights reserved.

Thrift N.,University of Warwick
Cultural Geographies | Year: 2012

This paper will consider how we might think about the capitalist economy that now seems to be emerging, one based on spontaneous synthesis. Following an extended introduction, the first part of the paper examines the main changes that have been taking place in the economy grouped around the notion and value of innovation. I will argue that these changes might be thought of as adding up to a second industrial revolution. Then, in the second part of the paper, I will consider how these changes are producing a different kind of production - one that is both industrial and cultural - which is constructing naturalism. The Industrial Revolution is often characterized as the first break in human history with the natural economy. But what if the natural economy was now being recovered - by other means - as a redefinition of what counts as land? In the final part of the paper, I will then turn to modern cities and the imprint that these changes are making upon them as this new land is founded and endowed and rented out to grow new kinds of crop upon. © The Author(s) 2012.

Tsolakis A.,University of Warwick
British Journal of Politics and International Relations | Year: 2010

Since the late 1980s, Open Marxism has focused on the conceptualisation of the relationship between global capital, the international system and the state-therein lies its original contribution to knowledge. This essay offers a sympathetic reflection on Open Marxist approaches to the state, which emphasises the strength of the definition 'organisation of subjection', yet argues that its validity is undermined by inadvertent structural-functionalist applications, by a tendency to view organisations of subjection as unitary 'political forms' and by assertions that the emergence of the international system is necessarily correlated to the historical globalisation of capital. The article offers a more nuanced alternative as fluid, contradictory organisation of subjection: as a social relation constituting and constituted by broader production relations, the state is a terrain of systematic intra-elite and class struggles. © 2010 The Author. Journal compilation © 2010 Political Studies Association.

Michail M.,University of Nottingham | Birchwood M.,University of Warwick
Journal of Affective Disorders | Year: 2014

Background Social anxiety is among the most prevalent affective disturbances among people with psychosis. The developmental pathways associated with its emergence in psychosis, however, remain unclear. The aim of this study is to identify the developmental risk factors associated with social anxiety disorder in first-episode psychosis and to investigate whether social anxiety in psychosis and non-psychosis is associated with similar or different adult attachment styles. Method This is a cross-sectional study. A sample of individuals with social anxiety disorder (with or without psychosis) was compared with a sample with psychosis only and healthy controls on childhood trauma, dysfunctional parenting and adult attachment. Results Childhood trauma and dysfunctional parenting (p<0.05) were significantly elevated in people with social anxiety (with or without psychosis) compared to those with psychosis only and healthy controls. There were no differences in childhood trauma and dysfunctional parenting between socially anxious people with and without psychosis. Higher levels of insecure adult attachment (x2 1=38.5, p<0.01) were reported in the social anxiety group (with or without psychosis) compared to the psychosis only and healthy controls. Childhood adversities were not associated with insecure adult attachment in people with social anxiety (with or without psychosis). Limitations Due to the cross-sectional nature of the study we cannot infer causal relationships between early risk factors, including childhood trauma and dysfunctional parenting, and social anxiety. Also, the use of self-report measures of attachment could be subject to biases. Conclusion Shared developmental risk factors are implicated in the emergence of affective disorders in psychosis and non-psychosis. Social anxiety in psychosis is associated with insecurity in adult attachments which does not arise a result of adverse developmental pathways. Understanding the bio-psycho-social risk factors for affective dysregulation in psychosis could inform psychological interventions about the role of developmental anomaly and trauma in the emergence of affective dysregulation in psychosis. © 2014 Elsevier B.V.

Robinson S.,University of Warwick
Proceedings - Winter Simulation Conference | Year: 2011

In performing a simulation study the modeler needs to make decisions about what to include in the simulation model and what to exclude. The modeler is faced with the very difficult choice of determining what is the best model to develop. Make it too complex and it may not be possible to complete the model with the time and knowledge available. Make it too simple and the results may not be sufficiently accurate. The process of determining what to model is known as conceptual modeling. In this paper we explore conceptual modeling first with an illustrative example from a healthcare setting. Conceptual modeling, its artefacts and requirements are then defined. Finally, a framework for helping a modeler to determine the conceptual model is briefly outlined. © 2011 IEEE.

Grant W.P.,University of Warwick
Policy and Society | Year: 2012

The contribution made by political science to the study of agricultural policy and the food chain is reviewed with an emphasis on the literature on interests. There is a fundamental question about 'Who benefits?' from government policy. Six general propositions are extracted from this literature and assessed. Directions for future theoretical and empirical work are discussed, it being argued that accounts of how policy agendas are constructed could be particularly helpful. Political science needs to move beyond its existing frameworks of analysis and develop a more interdisciplinary political economy approach. © 2012 Policy and Society Associates (APSS).

Kristensen S.R.,University of Manchester | Meacock R.,University of Manchester | Turner A.J.,University of Manchester | Boaden R.,University of Manchester | And 3 more authors.
New England Journal of Medicine | Year: 2014

BACKGROUND: A pay-for-performance program based on the Hospital Quality Incentive Demonstration was introduced in all hospitals in the northwest region of England in 2008 and was associated with a short-term (18-month) reduction in mortality. We analyzed the long-term effects of this program, called Advancing Quality. METHODS: We analyzed 30-day in-hospital mortality among 1,825,518 hospital admissions for eight conditions, three of which were covered by the financial-incentive program. The hospitals studied included the 24 hospitals in the northwest region that were participating in the program and 137 elsewhere in England that were not participating. We used difference-in-differences regression analysis to compare risk-adjusted mortality for an 18-month period before the program was introduced with subsequent mortality in the short term (the first 18 months of the program) and the longer term (the next 24 months). RESULTS: Throughout the short-term and the long-term periods, the performance of hospitals in the incentive program continued to improve and mortality for the three conditions covered by the program continued to fall. However, the reduction in mortality among patients with these conditions was greater in the control hospitals (those not participating in the program) than in the hospitals that were participating in the program (by 0.7 percentage points; 95% confidence interval [CI], 0.3 to 1.2). By the end of the 42-month follow-up period, the reduced mortality in the participating hospitals was no longer significant (-0.1 percentage points; 95% CI, -0.6 to 0.3). From the short term to the longer term, the mortality for conditions not covered by the program fell more in the participating hospitals than in the control hospitals (by 1.2 percentage points; 95% CI, 0.4 to 2.0), raising the possibility of a positive spillover effect on care for conditions not covered by the program. CONCLUSIONS: Short-term relative reductions in mortality for conditions linked to financial incentives in hospitals participating in a pay-for-performance program in England were not maintained. Copyright © 2014 Massachusetts Medical Society.

Recent technological developments have led to improvements in the strengths of materials, such as the steel and wire ropes used in the construction of cable supported bridges. This, combined with technological advancements in construction, has encouraged the design of structures with increasing spans, leaving the question of material and environmental costs behind. This paper presents a refined mathematical model for the assessment of relative material costs of the supporting structures for cable-stayed and cable suspension bridges. The proposed model is more accurate than the ones published to date in that it includes the self weight of the cables and the pylons. Comparisons of material requirements for each type of bridge are carried out across a range of span/dip ratios. The basis of comparison is the assumption that each structure is made of the same material (steel) and carries an identical design load, q, exerted by the deck. Calculations are confined to a centre span of a three-span bridge, with the size of the span ranging from 500. m to 3000. m. Results show that the optimum span/dip ratio, which minimises material usage, is 3 for a cable-stayed (harp type) bridge, and 5 for a suspension structure. The inclusion of the self weight of cable in the analysis imposes limits on either the span, or span/dip ratio. This effect is quantified and discussed with reference to the longest cable-supported bridges in the world completed to date and planned in the future. © 2012 Elsevier Ltd.

Thapper J.,University Paris - Sud