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Kiel, Germany

The Kiel University is a university in the city of Kiel, Germany. It was founded in 1665 as the Academia Holsatorum Chiloniensis by Christian Albert, Duke of Holstein-Gottorp and has approximately 24,000 students today. The University of Kiel is the largest, oldest, and most prestigious in the state of Schleswig-Holstein. Until 1864/66 it was not only the northernmost university in Germany but at the same time the 2nd largest university of Denmark. Wikipedia.


Bosch T.C.,University of Kiel
Gut microbes | Year: 2012

Any multicellular organism may be considered a metaorganism or holobiont-comprised of the macroscopic host and synergistic interdependence with bacteria, archaea, fungi, viruses, and numerous other microbial and eukaryotic species including algal symbionts. Defining the individual microbe-host conversations in these consortia is a challenging but necessary step on the path to understanding the function of the associations as a whole. Dissecting the fundamental principles that underlie all host-microbe interactions requires simple animal models with only a few specific bacterial species. Here I present Hydra as such a model with one of the simplest epithelia in the animal kingdom, with the availability of a fully sequenced genome and numerous genomic tools, and with few associated bacterial species. Source


Schaper F.,Otto Von Guericke University of Magdeburg | Rose-John S.,University of Kiel
Cytokine and Growth Factor Reviews | Year: 2015

Interleukin-6 (IL-6) is one of the most important inflammatory cytokines. IL-6 is unique in signaling via a membrane bound and a soluble receptor. Intriguingly, these two pathways strongly differ in their biologic consequences. While classic IL-6 signaling via the membrane bound receptor is mainly regenerative and protective, IL-6 trans-signaling via the soluble IL-6R is rather pro-inflammatory. Intracellular signaling of IL-6 in response to receptor activation is through STAT-dependent and STAT-independent signaling modules, which are regulated by a complex regulatory network. The complex biology of IL-6 has consequences for therapeutic targeting of this cytokine. We hypothesize that specific inhibition of the trans-signaling pathway may be superior to global blockade of IL-6 activity with help of antibodies directed against IL-6 or IL-6R. © 2015 Elsevier Ltd. Source


Therapeutic oral anticoagulation is still commonly achieved by administration of warfarin or other vitamin K antagonists that are associated with an untoward pharmacokinetic/pharmacodynamic (PK/PD) profile leading to a high incidence of bleeding complications or therapeutic failure. Hence, there is an unmet medical need of novel easy-to-use oral anticoagulants with improved efficacy and safety. Recent developments include the identification of non-peptidic small-molecules that selectively inhibit certain serine proteases within the coagulation cascade. Of these, the thrombin inhibitor dabigatran and factor Xa inhibitor rivaroxaban have recently been licensed for thromboprophylaxis after orthopaedic surgery mainly in Europe. In addition, the factor Xa inhibitor apixaban is in late-stage clinical development. Each drug is prescribed at fixed doses without the need of anticoagulant monitoring. Phase III trials in orthopaedic patients essentially resulted in non-inferior efficacy of dabigatran and superior efficacy of rivaroxaban over enoxaparin without any marked differences of drug safety, while apixaban data is still controversial. However, alterations of rivaroxaban and apixaban pharmacokinetics upon interactions with inhibitors and inducers of CYP3A4 or P-glycoprotein may complicate the use of these compounds in daily practice, whereas dabigatran elimination largely depends on renal function. Hence, this review reports PK/PD, efficacy and safety data of dabigatran, rivaroxaban and apixaban throughout preclinical and clinical development. © Schattauer 2010. Source


Pavlov V.V.,University of Kiel | Rashad A.M.,University of Stuttgart
Marine Mammal Science | Year: 2012

The impact of devices attached to animals remains a challenge in telemetry studies of dolphins. It was hypothesized that the hydrodynamic design of a tag could provide stable attachment to the dorsal fin by means of resultant hydrodynamic force appearing when a dolphin is swimming. To verify this hypothesis the computer fluid dynamics (CFD) study of tag performance was carried out. A virtual model presenting authentic geometry of a dolphin with tag attached to the dorsal fin was constructed. The same model without tag was used as a reference object to calculate tag impact as regards drag, lift, and moments coefficients. Flow around the models was simulated for the range of velocities as well as the ranges of pitch and yaw angles. It was shown that in 33 of 35 CFD scenarios the streamlined shape of a tag generates the lift force that facilitates keeping a tag attached to the fin. Throughout the set of calculations the tag-associated drag coefficient does not exceed 4%, which indicates low impact. Data obtained present a baseline for the further development of non-invasive dolphin telemetry tags. © 2011 by the Society for Marine Mammalogy. Source


Leypoldt F.,University of Barcelona | Leypoldt F.,University of Kiel | Armangue T.,University of Barcelona | Dalmau J.,University of Barcelona | And 2 more authors.
Annals of the New York Academy of Sciences | Year: 2015

Over the past 10 years, the continual discovery of novel forms of encephalitis associated with antibodies to cell-surface or synaptic proteins has changed the paradigms for diagnosing and treating disorders that were previously unknown or mischaracterized. We review here the process of discovery, the symptoms, and the target antigens of 11 autoimmune encephalitic disorders, grouped by syndromes and approached from a clinical perspective. Anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis, several subtypes of limbic encephalitis, stiff-person spectrum disorders, and other autoimmune encephalitides that result in psychosis, seizures, or abnormal movements are described in detail. We include a novel encephalopathy with prominent sleep dysfunction that provides an intriguing link between chronic neurodegeneration and cell-surface autoimmunity (IgLON5). Some of the caveats of limited serum testing are outlined. In addition, we review the underlying cellular and synaptic mechanisms that for some disorders confirm the antibody pathogenicity. The multidisciplinary impact of autoimmune encephalitis has been expanded recently by the discovery that herpes simplex encephalitis is a robust trigger of synaptic autoimmunity, and that some patients may develop overlapping syndromes, including anti-NMDAR encephalitis and neuromyelitis optica or other demyelinating diseases. © 2014 New York Academy of Sciences. Source


Paemeleire K.,Ghent University | Bartsch T.,University of Kiel
Neurotherapeutics | Year: 2010

Occipital nerve stimulation (ONS) was originally described in the treatment of occipital neuralgia. However, the spectrum of possible indications has expanded in recent years to include primary headache disorders, such as migraine and cluster headaches. Retrospective and some prospective studies have yielded encouraging results, and evidence from controlled clinical trials is emerging, offering hope for refractory headache patients. In this article we discuss the scientific rationale to use ONS to treat headache disorders, with emphasis on the trigeminocervical complex. ONS is far from a standardized technique at the moment and the recent literature on the topic is reviewed, both with respect to the procedure and its possible complications. An important way to move forward in the scientific evaluation of ONS to treat refractory headache is the clinical phenotyping of patients to identify patients groups with the highest likelihood to respond to this modality of treatment. This requires multidisciplinary assessment of patients. The development of ONS as a new treatment for refractory headache offers an exciting prospect to treat our most disabled headache patients. Data from ongoing controlled trials will undoubtedly shed new light on some of the unresolved questions. © 2010 The American Society for Experimental NeuroTherapeutics, Inc. Source


Hasler M.,University of Kiel
Pharmaceutical Statistics | Year: 2012

This paper addresses multiple comparisons in the presence of both a negative and a positive control. The methodology of the three-arm trial is extended to the case of many experimental treatment arms or different doses of a compound. In contrast to the classic three-arm trial, the focus is on the family-wise error type I. Normally distributed data with either homogeneous or heterogeneous group variances are considered. Explicit criteria for an optimal allocation are proposed. Depending on the pattern of heterogeneity, remarkably unbalanced designs are power-optimal. As an example, the method will be applied to a toxicological experiment. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd. Source


Schreiber S.,University of Kiel
Therapeutic Advances in Gastroenterology | Year: 2011

In this article we provide a contemporary overview of available clinical data on certolizumab pegol, a pegylated anti-tumor necrosis factor (TNF) alpha agent that comprises a uniquely small protein, and its emerging role as a therapy for Crohns disease (CD). The results from a comprehensive clinical trial program suggest that certolizumab pegol offers rapid and sustained remission of moderate to severe CD. Certolizumab pegol is an effective and well-tolerated therapy both in patients who have already received biologics and in patients who are anti-TNF naïve. Benefits of therapy include a stable dosing regimen, which allows for rapid induction of a clinical response followed by long-term maintenance of response and remission under one fixed dose. Treatment with certolizumab pegol has been shown to improve function and quality of life in patients with CD, and insights into the potential mechanisms by which certolizumab pegol effects a response in CD suggest that this agent may have the potential to slow or even modify disease progression. Early therapy is particularly effective and could help control CD progression and lessen the burden of disease on patients. © 2011 The Author(s). Source


Hosoda N.,Japan National Institute of Materials Science | Gorb S.N.,University of Kiel
Proceedings of the Royal Society B: Biological Sciences | Year: 2012

For the first time, we report the remarkable ability of the terrestrial leaf beetle Gastrophysa viridula to walk on solid substrates under water. These beetles have adhesive setae on their feet that produce a secretory fluid having a crucial role in adhesion on land. In air, adhesion is produced by capillary forces between the fluid-covered setae and the substrate. In general, capillary forces do not contribute to adhesion under water. However, our observations showed that these beetles may use air bubbles trapped between their adhesive setae to walk on flooded, inclined substrata or even under water. Beetle adhesion to hydrophilic surfaces under water was lower than that in air, whereas adhesion to hydrophobic surfaces under water was comparable to that in air. Oil-covered hairy pads had a pinning effect, retaining the air bubbles on their feet. Bubbles in contact with the hydrophobic substrate de-wetted the substrate and produced capillary adhesion. Additional capillary forces are generated by the pad's liquid bridges between the foot and the substrate. Inspired by this idea, we designed an artificial silicone polymer structure with underwater adhesive properties. © 2012 The Royal Society. Source


Jansen O.,University of Kiel | Macho J.M.,University of Barcelona | Killer-Oberpfalzer M.,Paracelsus Medical University | Liebeskind D.,University of California at Los Angeles | Wahlgren N.,Karolinska University Hospital
Cerebrovascular Diseases | Year: 2013

Background: Fast recanalization has been shown to be one of the most important factors for good clinical outcome in stroke patients with acute large vessel occlusion. While intravenous thrombolysis has been shown to be of limited effect in patients with large clot burden, intra-arterial neurothrombectomy offers a new and promising possibility to achieve high recanalization rates within a short time. The Trevo device is a stent-like retriever and was primarily designed to remove thrombus in patients experiencing an acute ischemic stroke. We report on the results of the TREVO Study, which was a prospective, multicenter study in acute stroke patients treated with the Trevo device. Methods: Patients were recruited in seven European centers under the control of an external monitor. Centers were selected because of their long experience with interventional stroke therapy especially with neurothrombectomy. We included adults aged 18-85 years with angiographically confirmed large vessel occlusion strokes and NIHSS scores of 8-30 and treatable within 8 h of symptom onset. The primary endpoint was revascularization, defined as at least TICI (thrombolysis in cerebral infarction) 2a. The revascularization scores were assessed by an independent core lab. Secondary endpoints were clinical outcome at 90 days (mRS 90), any device-related serious adverse events and the rate of symptomatic intracerebral hemorrhages. Results: 60 patients were enrolled. The overall recanalization rate (≥TICI 2a) was 91.7% and TICI 2b and 3 was achieved in 78.3%. At 90 days, 55% of the patients had a favorable neurological outcome (mRS 0-2) and 20% had died. Patients with successful recanalization (TICI 2a,b/3) had a good 90-day neurological outcome (mRS 0-2) in 60%, whereas no patient without recanalization had a mRS 90 <3. The overall rate of symptomatic intracerebral hemorrhage according to the SITS-MOST criteria was 5% (3/60). Conclusions: The study suggest that the Trevo Stentriever™ is a safe and effective device, which may offer the possibility of a high reperfusion rate and a high rate of patients with good clinical outcome after acute ischemic stroke due to proximal arterial occlusion. Randomized trials comparing intravenous thrombolysis with neurothrombectomy are now urgently needed to evaluate this new approach of interventional stroke therapy. Copyright © 2013 S. Karger AG, Basel. Source


Christophers E.,University of Kiel | Metzler G.,University of Tubingen | Rocken M.,University of Tubingen
British Journal of Dermatology | Year: 2014

Psoriasis is an immune-regulated skin disease with various clinical subtypes and disease activities. The majority of patients present with predominantly stable plaques. At the onset of new lesions, plaque-type psoriasis frequently demonstrates pin-sized and highly inflammatory papules sometimes with an inflammatory border. The histopathology of initial psoriasis differs from stable plaque-type psoriasis. Early lesions demonstrate innate immune cells with neutrophils, degranulating mast cells and macrophages. These are followed by interleukin (IL)-1-dependent T helper (Th)17 cells, finally resulting in the Th1-dominated immunopathology of stable plaque-type psoriasis, where mononuclear cells predominate with interspersed neutrophilic (Munro) microabscesses. These features suggest a bimodal immune pathway where alternate activation of either innate (autoinflammatory) or adaptive (autoimmune) immunity predominates. Neutrophilic infiltrations appear during early psoriasis with Munro abscesses. They are time limited and occur periodically, clinically best seen in linear nail pitting. These features strongly suggest a critical role for an IL-1-Th17-dominated autoinflammation in the initiation of psoriasis, followed by a Th1-dominated late-phase reaction. The concept of bimodal immune activation helps to explain results from therapeutic interventions that are variable and previously only partly understood. What's already known about this topic? The understanding of psoriasis has greatly advanced over the past 20 years. It started by recognizing psoriasis as a T-cell-mediated disease caused by interferon-producing T cells. Important roles for interleukin (IL)-1-related molecules have been uncovered, and partially underlined by clinical studies. Because of the importance of different mediators such as tumour necrosis factor (TNF) and IL-1, and T helper (Th)1 and Th17 immunity, psoriasis is increasingly viewed as a plethora of different diseases. What does this study add? Joining insights from genetics and immunology with clinical and histological pictures of single psoriasis lesions, here we suggest that psoriasis is one disease complex that appears at different levels. Psoriasis starts as an IL-1-TNF-mediated, neutrophil-dominated inflammation that initiates a Th17/Th22-dominated early T-cell infiltrate that turns into a Th1-dominated psoriasis plaque. Such plaques are sustained periodically by IL-1-TNF-producing squirting papillae that steadily deliver new psoriasis foci inside the lesion. © 2013 British Association of Dermatologists. Source


Lagaly G.,University of Kiel | Dekany I.,Hungarian Academy of Sciences
Developments in Clay Science | Year: 2013

The knowledge of the properties of colloidal dispersions is fundamental for designing and optimizing the usage of clays and clay minerals. The colloidal behaviour of these dispersions is very complex due to the anisometric (and often irregular) particle shape, the anisometric and pH-dependent charge distribution, the variable particle dimensions as a consequence of swelling, delamination and exfoliation, and the ion-exchange properties. Therefore, this chapter gives information on the structure, charge distribution, structure of the hydrates, diffuse ionic layer, and the interactions between the colloidal clay mineral particles (electrostatic, van der Waals, ion correlation, steric stabilization). A large section refers to the coagulation of clay mineral dispersions by salts, the influence of organic compounds, and the destabilization (flocculation by bridging or charge neutralization) or stabilization by polymers (by recharging or steric stabilization). In a further section is described the aggregation of clay mineral particles leading to different types of sediments (decisively determining sealing, plastering, stirring, filtration processes, plasticity) or resulting in gel formation, often with thixotropic properties. Also mentioned is the preparation of colloidal metal (hydr)oxides and sulphides within the network of clay mineral particles or even between the clay mineral layers. © 2013 Elsevier Ltd. Source


Bergaya F.,French National Center for Scientific Research | Lagaly G.,University of Kiel
Developments in Clay Science | Year: 2013

Clays and clay minerals are recognized as the materials of the twenty-first century. Chapter 1 provides a general introduction into clay science, illustrates the classification of the clay minerals (planar and non-planar 1:1 and 2:1 clay minerals), shows the idealized formulae of some representative clay minerals, lists the current names of clays, and reports the important properties of clay minerals. As yet, there is no uniform nomenclature in clay science, a unifying terminology is proposed that should be acceptable to all disciplines, users, and producers. This mainly concerns the terms "clay and clay mineral", "associated minerals and associated phases", "particles and aggregates", "swelling", and "delamination and "exfoliation". Finally, in addition to belonging to the class of silicates, three alternative concepts of clay minerals are proposed to extend the benefit to a wider scientific audience. © 2013 Elsevier Ltd. Source


Ernst A.,University of Kiel
Palaeobiodiversity and Palaeoenvironments | Year: 2013

Bryozoan diversity during the Devonian period displays a persistent rise from the Pragian to the early Givetian, significantly dropping in the late Givetian in the wake of the Taghanic Event. In contrast, two other important events during the Devonian, the Frasne/Famenne Event and the Hangenberg Event at the Devonian/Carboniferous boundary, were less significant and resulted mainly in shifts in faunal composition. Diversity dynamics of Devonian Bryozoa was apparently controlled by extrinsic and intrinsic factors. Global palaeogeographic settings influenced faunal provincialism to which bryozoans seem to be sensitive. Sea-level fluctuations and subsequent changes in suitability of habitats influenced biodiversification processes in bryozoans. Intrinsically, bryozoans show some patterns consistent with diffuse co-evolution with potential predators and, possibly, prey. Observed trends in the morphological evolution of Devonian bryozoans include some obvious anti-predator adaptations (protective structures, strengthened skeletal walls). Moreover, Devonian bryozoans often developed various internal modifications, which apparently influenced the activity of polypides. This pattern is regarded here as apparent improvement of feeding, possibly as a response to diminishing food in the course of the mid-Palaeozoic Phytoplankton Blackout. © 2012 Senckenberg Gesellschaft für Naturforschung and Springer. Source


de Kraker A.M.J.,VU University Amsterdam | Fernandes R.,University of Kiel
Climatic Change | Year: 2013

This paper investigates the correlation between monthly average temperatures and tithe leasing dates in the Low Countries between 1600 and 1810. The information was obtained from manorial tithe leasing records distributed across the Netherlands and Belgium. Similar research in France and in Switzerland relied on annual dates of grape harvest as a temperature proxy and provided a strong correlation between harvest dates and average monthly temperatures. However, the analysis of our data indicates a low correlation between average monthly temperatures, using the Labrijn temperature series, and tithe leasing dates. Possible reasons for this behaviour include soil variety, diversity in crop growth patterns, historical factors, and variety of crop types. The complexity of variables, therefore, does not permit for the usage of tithe leasing dates for ancient temperature reconstruction. Nonetheless, useful information on crop behaviour under extreme climatic conditions was obtained. © 2013 Springer Science+Business Media Dordrecht. Source


Several meta-analyses have demonstrated that the combination of electrical muscle activity and Temperature Biofeedback could be regarded as gold standard in chronic pediatric headaches. However, these techniques seem to be uneconomical and furthermore they are not directed to improve the social competence as well as resolve possible impairments in daily activities of the child. Therefore, multi-modal behavioral techniques have been proposed, but no studies comparing these with the gold standard were conducted. The present study compared the impact of a new multi-modal behavioral education and training program--MIPAS-Family--with a combined Biofeedback treatment, evaluating clinical efficacy as well as the effect on the quality of life (QoL) of children with chronic headaches. Thirty-four children and adolescents with recurrent headache, ranging from 7 to 16 years, were randomly assigned to the MIPAS-Family (N = 19) or the Biofeedback (N = 15) condition. All patients were diagnosed by the criteria of the International Headache Society. The children and their parents completed headache diaries, diaries of daily living activities and a QoL questionnaire (KINDL). Both groups showed significant improvements concerning the headache intensity and headache duration. We found no significant differences in the main headache parameters between both treatments. After the treatments, the children were less disturbed by their headaches in the domains school, homework, and leisure time. In conclusion, MIPAS-Family is as effective as Biofeedback but it is more cost-effective and addresses the whole family and the daily activities. Source


Wohlfahrt G.,University of Innsbruck | Widmoser P.,University of Kiel
Agricultural and Forest Meteorology | Year: 2013

Elucidating the causes for the energy imbalance, i.e. the phenomenon that eddy covariance latent and sensible heat fluxes fall short of available energy, is an outstanding problem in micrometeorology. This paper tests the hypothesis that the full energy balance, through incorporation of additional independent measurements which determine the driving forces of and resistances to energy transfer, provides further insights into the causes of the energy imbalance and additional constraints on energy balance closure options. Eddy covariance and auxiliary data from three different biomes were used to test five contrasting closure scenarios. The main result of our study is that except for nighttime, when fluxes were low and noisy, the full energy balance generally did not contain enough information to allow further insights into the causes of the imbalance and to constrain energy balance closure options. Up to four out of the five tested closure scenarios performed similarly and in up to 53% of all cases all of the tested closure scenarios resulted in plausible energy balance values. Our approach may though provide a sensible consistency check for eddy covariance energy flux measurements. © 2012 Elsevier B.V. Source


Stickel F.,University of Bern | Hampe J.,University of Kiel
Gut | Year: 2012

Alcoholic liver disease (ALD) accounts for the majority of chronic liver disease in Western countries. The spectrum of ALD includes steatosis with or without fibrosis in virtually all individuals with an alcohol consumption of >80 g/day, alcoholic steatohepatitis of variable severity in 10-35% and liver cirrhosis in approximately 15% of patients. Once cirrhosis is established, there is an annual risk for hepatocellular carcinoma of 1-2%. Environmental factors such as drinking patterns, coexisting liver disease, obesity, diet composition and comedication may modify the natural course of ALD. Twin studies have revealed a substantial contribution of genetic factors to the evolution of ALD, as demonstrated by a threefold higher disease concordance between monozygotic twins and dizygotic twins. With genotyping becoming widely available, a large number of genetic case-control studies evaluating candidate gene variants coding for proteins involved in the degradation of alcohol, mediating antioxidant defence, the evolution and counteraction of necroinflammation and formation and degradation of extracellular matrix have been published with largely unconfirmed, impeached or even disproved associations. Recently, whole genome analyses of large numbers of genetic variants in several chronic liver diseases including gallstone disease, primary sclerosing cholangitis and non-alcoholic fatty liver disease (NAFLD) have identified novel yet unconsidered candidate genes. Regarding the latter, a sequence variation within the gene coding for patatin-like phospholipase encoding 3 (PNPLA3, rs738409) was found to modulate steatosis, necroinflammation and fibrosis in NAFLD. Subsequently, the same variant was repeatedly confirmed as the first robust genetic risk factor for progressive ALD. Source


Hartke B.,University of Kiel
Wiley Interdisciplinary Reviews: Computational Molecular Science | Year: 2011

The current status of global optimization in computational molecular science is characterized in this article by focusing on one particular area, evolutionary algorithms applied to cluster structure optimization. Other algorithms and application areas are also mentioned briefly, indicating a widespread use of global optimization techniques in every conceivable branch of computational molecular science. © 2011 John Wiley & Sons, Ltd. Source


Bosch T.C.G.,University of Kiel | McFall-Ngai M.J.,University of Wisconsin - Madison
Zoology | Year: 2011

Because it appears that almost all organisms are part of an interdependent metaorganism, an understanding of the underlying host-microbe species associations, and of evolution and molecular underpinnings, has become the new frontier in zoology. The availability of novel high-throughput sequencing methods, together with the conceptual understanding that advances mostly originate at the intersection of traditional disciplinary boundaries, enable biologists to dissect the mechanisms that control the interdependent associations of species. In this review article, we outline some of the issues in inter-species interactions, present two case studies illuminating the necessity of interfacial research when addressing complex and fundamental zoological problems, and show that an interdisciplinary approach that seeks to understand co-evolved multi-species relationships will connect genomes, phenotypes, ecosystems and the evolutionary forces that have shaped them. We hope that this article inspires other collaborations of a similar nature on the diverse landscape commonly referred to as " zoology". © 2011 Elsevier GmbH. Source


Schaumloffel D.,University of Pau and Pays de lAdour | Tholey A.,University of Kiel
Analytical and Bioanalytical Chemistry | Year: 2011

A brief survey is given of the last 2 years' literature on electrospray mass spectrometry (ESI-MS) for speciation analysis. As observed for many years, the main recent applications in this field concern arsenic and selenium species, especially in studies encompassing combined use of molecular and element mass spectrometry. A further application field is the stoichiometric characterization of metal complexes by ESI-MS, which in some studies was assisted by nuclear magnetic resonance spectroscopy. A few examples are presented to illustrate arsenic species involved in metabolic pathways, sulfur species in oils and bitumen, and aluminum complexes. On the basis of this review, we also give an outlook of expected future developments and trends in this research field. © 2011 Springer-Verlag. Source


Petruzzelli M.,Spanish National Cancer Research Center | Schweiger M.,University of Graz | Schreiber R.,University of Graz | Campos-Olivas R.,Spectroscopy and Nuclear Magnetic Resonance Unit | And 8 more authors.
Cell Metabolism | Year: 2014

Summary Cancer-associated cachexia (CAC) is a wasting syndrome characterized by systemic inflammation, body weight loss, atrophy of white adipose tissue (WAT) and skeletal muscle. Limited therapeutic options are available and the underlying mechanisms are poorly defined. Here we show that a phenotypic switch from WAT to brown fat, a phenomenon termed WAT browning, takes place in the initial stages of CAC, before skeletal muscle atrophy. WAT browning is associated with increased expression of uncoupling protein 1 (UCP1), which uncouples mitochondrial respiration toward thermogenesis instead of ATP synthesis, leading to increased lipid mobilization and energy expenditure in cachectic mice. Chronic inflammation and the cytokine interleukin-6 increase UCP1 expression in WAT, and treatments that reduce inflammation or β-adrenergic blockade reduce WAT browning and ameliorate the severity of cachexia. Importantly, UCP1 staining is observed in WAT from CAC patients. Thus, inhibition of WAT browning represents a promising approach to ameliorate cachexia in cancer patients. © 2014 Elsevier Inc. All rights reserved. Source


Plieth C.,University of Kiel
Plant Signaling and Behavior | Year: 2010

Plants respond to almost any kind of external stimulus with transients in their cytoplasmic free calcium concentration ([Ca2+]c). A huge variety of kinetics recorded by optical techniques has been reported in the past. This variety has been credited the specificity needed to explain how information about incoming stimuli is evaluated by the organism and turned into the right physiological responses which provide advantages for survival and reproduction. A physiological response often takes place away from the site of stimulation. This requires cell-to-cell communication. Hence, responding cells are not necessarily directly stimulated but rather receive an indirect stimulus via cell-to-cell communication. It appears unlikely that the '[Ca2+]c signature' in the primarily stimulated cell is conveyed over long distances via cell-to-cell communication from the 'receptor cells' to the 'effector cells'. Here, a novel aspect is highlighted to explain the variety of [Ca2+] kinetics seen by integrating methods of [Ca2+]c recording. Plants can generally be seen as cellular automata with specific morphology and capable for cell-to-cell communication. Just a few rules are needed to demonstrate how waves of [Ca2+]c-increases percolate through the organism and thereby deliver a broad variety of 'signatures'. Modelling intercellular signalling may be a possible way to find explanations for different kinds of signal transmission, signal amplification, wave formation, oscillations and stimulus-response coupling. The basic examples presented here show that care has to be taken when interpreting cellular '[Ca2+]c signatures' recorded by optical techniques which integrate over a big number of cells or even whole plants. © 2010 Landes Bioscience. Source


The paper is concerned with the 'edge of intonation' in a twofold sense. It focuses on utterance-final F0 movements and crosses the traditional segment-prosody divide by investigating the interplay of F0 and voiceless fricatives in speech production. An experiment was performed for German with four types of voiceless fricatives: /f/, /s/, /Latin small letter esh/ and /x/. They were elicited with scripted dialogues in the contexts of terminal falling statement and high rising question intonations. Acoustic analyses show that fricatives concluding the high rising question intonations had higher mean centres of gravity (CoGs), larger CoG ranges and higher noise energy levels than fricatives concluding the terminal falling statement intonations. The different spectral-energy patterns are suitable to induce percepts of a high 'aperiodic pitch' at the end of the questions and of a low 'aperiodic pitch' at the end of the statements. The results are discussed with regard to the possible existence of 'segmental intonation' and its implication for F0 truncation and the segment-prosody dichotomy, in which segments are the alleged troublemakers for the production and perception of intonation. Copyright © 2012 S. Karger AG, Basel. Source


Several decades of research, focusing on English, Dutch and German, have set up a hierarchy of acoustic properties for cueing lexical stress. It attributes the strongest cue to criterial-level f0 change, followed by duration, but low weight to energy and to stressed-vowel spectra. This paper re-examines the established view with new data from German. In the natural productions of the German word pair Kaffee 'coffee' - Café 'locality' (with initial vs. final stress in a North German pronunciation), vowel duration was manipulated in a complementary fashion across the two syllables in five steps, spanning the continuum from initial to final stress on each word. The two base words provided different vowel qualities as the second variable, the intervocalic fricative was varied in two values, long and short, taken from Café and Kaffee, and the generated test words were inserted in a low f0 tail and in a high f0 hat-pattern plateau, which both eliminated f0 change as a cue to lexical stress. The sentence stimuli were judged in two listening experiments by 16 listeners in each as to whether the first or the second syllable of the test word was stressed. The results show highly significant effects of vowel duration, vowel quality and fricative duration. The combined vowel-quality and fricative variable can outweigh vowel duration as a cue to lexical stress. The effect of the prosodic frame is only marginal, especially related to a rhythmic factor. The paper concludes that there is no general hierarchy with a fixed ranking of the variables traditionally adduced to signal lexical stress. Every prosodic embedding of segmental sequences defines the hierarchy afresh. Copyright © 2012 S. Karger AG, Basel. Source


Reinsch H.,University of Kiel
European Journal of Inorganic Chemistry | Year: 2016

Research in the field of metal-organic frameworks (MOFs) has been for a long time devoted to the synthesis of new compounds and the understanding of their outstanding properties. Just in the recent four or five years there has been an emerging interest in up-scaling of synthesis procedures and the adjustment of synthesis conditions towards industrial requirements. This probably originates from the fact that, while some MOFs are already commercially available, there is still no field of application in real life which MOFs are able to fit in. One reason for this might be the attributed to the common synthetic procedures which are often unsuitable for preparations at pilot or industrial scale. Thus a recent focus in MOF research is the finding of synthesis conditions which employ non-hazardous reactants at relatively mild synthetic conditions, producing also less waste than conventional procedures. In brief: The "green" synthesis of MOFs. This microreview is intended to give some examples of the efforts made in this field of research and show some perspectives for the future. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Egorova D.,University of Kiel
Journal of Physical Chemistry A | Year: 2014

The specific origin of oscillations in time-resolved optical signals, in particular, for complex systems with nontrivial interstate couplings and nonseparable electron-nuclear motion, is often difficult to assign. Here, we show that coherent oscillations in two-dimensional photon-echo are capable of self-analysis; their beating maps provide a tool to tell apart ground-state bleach (GSB), stimulated emission (SE), and excited-state absorption (ESA) contributions to the oscillatory signal component. Because GSB carries information on ground-state coherence while SE and ESA reflect the excited-state coherence, the observed oscillations can be unambiguously assigned to ground-state or excited-state coherent motion. The findings prove especially advantageous for systems with dense detectable manifolds of states pertaining to each electronic state. An analogous analysis for frequency-resolved (dispersed) pump-probe spectroscopy is discussed briefly. (Formula Presented). © 2014 American Chemical Society. Source


Helbig I.,Childrens Hospital of Philadelphia | Helbig I.,University of Kiel
Seminars in Neurology | Year: 2015

Generalized epilepsies, particularly the idiopathic or genetic generalized epilepsies (GGEs), represent some of the most common epilepsies. Clinical genetic data including family studies and twin studies provide compelling evidence for a prominent genetic impact. The first decade of the 21st century was marked by progress in understanding the basic biology of generalized epilepsies including generalized/genetic epilepsies with febrile seizures plus (GEFS+) and GGE through studies of large families, discovering causative mutations in SCN1A, SCN1B, GABRG2, and GABRA1. Subsequently, recurrent microdeletions at 15q13.3, 16p13.11, and 15q11.2 were found to be relevant risk factors for nonfamilial GGE. Genes for epileptic encephalopathies such as SLC2A1 were rediscovered in GGE, highlighting the biological continuum between different epilepsies. Genome-wide studies examining common genetic risk factors identified common variants in SCN1A, indicating a convergence of shared pathophysiological pathways in various types of epilepsies. In the era of next-generation sequencing, however, the GGEs appear more complex than expected, and small or moderately sized studies give only a limited genetic perspective. Thus, there is a strong impetus for large collaborative investigations on an international level. © 2015 by Thieme Medical Publishers, Inc. Source


Muller-Buschbaum H.,University of Kiel
Zeitschrift fur Anorganische und Allgemeine Chemie | Year: 2011

This review describes features of the crystal chemistry of oxoniccolates containing large cations like alkali-, alkaline earth and rare earth metals. Starting with alkali-oxoniccolates it is shown that Ni + exhibits the unusual coordination number CN = 2 (dumbbells) in K 2/ Rb 2/ Na 2NiO 2 and K 3NiO 2. K 2NiO 2 is the only known oxoniccolat showing O-Ni-O-dumbbells with nickel in the oxidation state Ni 2+. The trigonal planar coordination (found within silver-oxocompounds) is restricted to Ba 3NiO 4 and K 9Ni 2O 7. Square planar polygons (NiO 4) are found in Nd 4Ni 3O 8; Na 2NiO 2; Ki 2NiO 2; BaNiO 2 and SrNiO 2 for example. A special quality in the crystal chemistry of connected square planar NiO 4-polygons is the formation of Ni 6O 12-rings in Ba 2NaNi 3O 6. There are two compounds showing Ni 3+O 4-tetrahedra: K 9Ni 2O 7 and Na 5NiO 4. All the other oxoniccolates exhibit octahedral or trigonal prismatic coordination of nickel by oxygen. Always of interest are the so called one dimensional oxides, showing chains of two times face-shared octahedra and/or trigonal prisms, found in Sr 3Yb 0.89NiO 6, Sr 3PbNiO 6; Sr 12Ni 7.5O 27; Sr 4Ni 3O 9; BaNi 0.83O 2.5 and NaSr 12Ni 7O 23. Large chains of the type -[(octahedron) 2-(prism)-(octahedron) 2-prism-(octahedron) 3-(prism)-(octahedron) 2-(prism)-(octahedron) 2]- filled by Ni 3+ and Ni 4+ are found in Sr 9Ni 6.64O 21. Many of the oxidation states of nickel are published with non integral valence states like Ni 2.667+, Ni 2.5+, Ni 2.292+, Ni 3.614. Using calculations of the Coulomb-terms of lattice energy most of the mixed valences could be split up in integral numbers protecting the electro neutrality between metal ions and oxygen. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Rossnagel K.,University of Kiel
Journal of Physics Condensed Matter | Year: 2011

The occurrence of charge-density waves in three selected layered transition-metal dichalcogenides - 1T-TaS2, 2H-TaSe2 and 1T-TiSe2 - is discussed from an experimentalist's point of view with a particular focus on the implications of recent angle-resolved photoelectron spectroscopy results. The basic models behind charge-density-wave formation in low-dimensional solids are recapitulated, the experimental and theoretical results for the three selected compounds are reviewed, and their band structures and spectral weight distributions in the commensurate charge-density-wave phases are calculated using an empirical tight-binding model. It is explored whether the origin of charge-density waves in the layered transition-metal dichalcogenides can be understood in a unified way on the basis of a few measured and calculated parameters characterizing the interacting electron-lattice system. It is found that the predictions of the standard mean-field model agree only semi-quantitatively with the experimental data and that there is not one generally dominant factor driving charge-density-wave formation in this family of layer compounds. The need for further experimental and theoretical scrutiny is emphasized. © 2011 IOP Publishing Ltd. Source


Grasner J.-T.,University of Kiel | Bossaert L.,University of Antwerp | Bossaert L.,Universiteitsplein 1
Best Practice and Research: Clinical Anaesthesiology | Year: 2013

Major European institutions report cardiovascular disease (CVD) as the first cause of death in adults, with cardiac arrest and sudden death due to coronary ischaemia as the primary single cause. Global incidence of CVD is decreasing in most European countries, due to prevention, lifestyle and treatment. Mortality of acute coronary events inside the hospital decreases more rapidly than outside the hospital. To improve the mortality of cardiac arrest outside the hospital, reliable epidemiological and process figures are essential: "we can only manage what we can measure". Europe is a patchwork of 47 countries (total population of 830 million), with a 10-fold difference in incidence of coronary heart disease between North and South, East and West, and a 5-fold difference in number of EMS-treated cardiac arrest (range 17-53/1000,000/year). Epidemiology of cardiac arrest should not be calculated as a European average, but it is appropriate to describe the incidence of cardiac arrest, the resuscitation process, and the outcome in each of the European regions, for benchmarking and quality management. Epidemiological reports of cardiac arrest should specify definitions, nominator (number of cases) and denominator (study population). Recently some regional registries in North America, Japan and Europe fulfilled these conditions. The European Registry of Cardiac Arrest (EuReCa) has the potential to achieve these objectives on a pan-European scale. For operational applications, the Utstein definition of "Cardiac arrest" is used which includes the potential of survival. For application in community health, the WHO definition of "sudden death" is frequently used, describing the mode of death. There is considerable overlap between both definitions. But this explains that no single method can provide all information. Integrating data from multiple sources (local, national, multinational registries and surveys, death certificates, post-mortem reports, community statistics, medical records) may create a holistic picture of cardiac arrest in the community. © 2013 Elsevier Ltd. All rights reserved. Source


Makarewicz C.A.,University of Kiel | Sealy J.,University of Cape Town
Journal of Archaeological Science | Year: 2015

The use of stable isotope ratio analysis in archaeology has exploded over the past few decades to the point where it is now an established tool that is routinely used to investigate questions relating to diet and mobility. Early applications focused mostly on the analysis of human skeletal tissues as a way to reconstruct major shifts in human diet, but current stable isotopic approaches have expanded to include high resolution analyses of human, animal, and plant remains, which are helping to better define the resource exploitation and management strategies that underscore changes in the human diet. In addition, stable isotopic data sets are now regularly filtered through interpretive archaeological theoretical frameworks to explore socially mediated food acquisition and consumption choices, mortuary practices, and social identity. Much work remains to be done in documenting the biological and ecological variation in the distribution of stable isotopes in ancient food webs and the mechanisms responsible for the isotopic signals observed in archaeological plant and animal tissues. Here, we identify several areas in stable isotope analysis where additional 'first principles' driven research would help to improve existing isotopic methods, or develop new ones, and consequently improve our ability to answer questions of archaeological significance. We consider the strengths and limitations of the application of stable isotope analysis to ancient skeletal material obtained from archaeological contexts. We also pay particular attention to nitrogen isotopic variation in ancient ecosystems, organic oxygen and hydrogen isotopes to;mixing models as a means of estimating source contributions in human diet, mobility, and isoscapes; and to how compound specific analyses may help detangle dietary routing. We conclude with a plea for greater scientific rigour and more informed use of stable isotope analyses and call for a closer integration of stable isotope analysis with other aspects of archaeological research programmes, in order to optimise the information that isotopes can provide. © 2015 . Source


Thi Ngoc Ha N.,TU Chemnitz | Gopakumar T.G.,University of Kiel | Hietschold M.,TU Chemnitz
Journal of Physical Chemistry C | Year: 2011

Self-assembly at the liquid-solid interface is controlled by concentration of solute in solvent. Trimesic acid (TMA) dissolved in fatty acids shows a polymorphism on HOPG surface tuned by its concentration at the solid-liquid interface via sonication of the solution. According to literature, TMA at long chain length fatty acids (C n-1H 2n-1COOH)-HOPG interface, such as octanoic acid (n = 8) and nonanoic acid (n = 9) can only form low-packing density chicken-wire structure, whereas in short-chain length solutions (ranging from butyric acid (n = 4) to heptanoic acid (n = 7)), high-packing density flower structure is formed. Here we show that by adjusting the molecule concentration by sonication (using an ultrasonic bath), the different polymorphs can be deposited in a controlled manner, and it turns out that the observations previously made(1)are valid only within a small window of low concentrations. © 2011 American Chemical Society. Source


Zelenka C.,University of Kiel
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

This work focuses on the precise quantification of bubble streams from underwater gas seeps. The performance of the snake based method and of ellipse fitting with the CMA-ES non-linear optimization algorithm is evaluated. A novel improved snake based method is presented and the optimal choice of snake parameters is studied. A Kalman filter is used for bubble tracking. The deviation between the measured flux and a calibrated flux meter is 4% for small and 9% for larger bubbles. This work will allow a better data gathering on marine gas seeps for future climatology and marine research. © Springer International Publishing Switzerland 2014. Source


In situ real-time angle-resolved photoelectron spectroscopy is used to measure the electronic structure changes at the surfaces of the layered charge-density-wave materials 1T-TiSe2 and 1T-TaS2 during Rb deposition. For 1T-TiSe2, Rb adsorption at a sample temperature of 80 K causes a transition from a dirty semiconductor to a metal, in the course of which the p(2 × 2 × 2) charge-density wave is completely suppressed. For 1T-TaS2, Rb adsorption at room temperature is rapidly followed by intercalation, leading to a pronounced metal-to-insulator transition that is correlated with a structural change from the pristine nearly commensurate p(√13 × √13)R13.9° superlattice to a commensurate c(2√3 × 4)rect. charge-density-wave phase. The implications of the results on the charge-density-wave mechanisms in both compounds are discussed with particular reference to the possible interplay of electron-phonon and electron-electron interactions. It is suggested that strong electron-phonon coupling drives the charge-density wave (CDW) phase transitions in pristine 1T-TiSe2 as well as in Rb intercalated 1T-TaS 2, i.e. the transitions are interpreted as primarily Peierls-like instabilities or, in other words, Jahn-Teller band instabilities. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft. Source


Michta D.,Lawrence Livermore National Laboratory | Michta D.,Princeton Plasma Physics Laboratory | Graziani F.,Lawrence Livermore National Laboratory | Bonitz M.,University of Kiel
Contributions to Plasma Physics | Year: 2015

The idea to describe quantum systems within a hydrodynamic framework (quantum hydrodynamics, QHD) goes back to Madelung and Bohm. While such a description is formally exact for a single particle, more recently the concept has been applied to many-particle systems by Manfredi and Haas [Phys. Rev. B 64, 075316 (2001)] and received high popularity in parts of the quantum plasma community. Thereby, often the applicability limits of these equations are ignored, giving rise to unphysical predictions. Here we demonstrate that modified QHD equations for plasmas can be derived from Thomas-Fermi theory including gradient corrections. This puts QHD on firm grounds. At the same time this derivation yields a different prefactor, γ = (D - 2/3D), in front of the quantum (Bohm) potential which depends on the system dimensionality D. Our approach allows one to identify the limitations of QHD and to outline systematic improvements. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Al Hagrey S.A.,University of Kiel
Leading Edge (Tulsa, OK) | Year: 2011

The need to manage CO2 emissions for mitigating the greenhouse effect has led to worldwide research to reduce atmospheric CO2. Techniques of carbon capture and storage (CCS) must (1) be effective and cost-competitive, (2) provide stable, long-term storage, and (3) be environmentally benign. Potential terrestrial media for CO2 storage include depleted oil and gas reservoirs, coal seams that cannot be mined, and deep saline water reservoirs capped by impermeable rock to prevent upward leakage. © 2011 Society of Exploration Geophysicists. Source


Available evidence suggests that overweight and obesity prevalence is increasing worldwide at an alarming rate in both developed and developing countries. This study focuses on the determinants of overweight in mothers and children, using a unique dataset collected in urban Accra, in Ghana. The findings show that mothers' education, employment status and ethnicity significantly exert influence on the generation of body weight. In particular, those who attained secondary and tertiary education had lower body mass indices and were much less likely to be overweight or obese, lending support to the notion that more educated women normally have better health knowledge and are more likely to consume healthy foods and also engage in physical exercises that help to control weight gain. Mother's education was also found to exert a negative and significant impact on the weight status of children. Furthermore, household expenditure was found to exert a positive and significant impact on the probability of a mother being overweight or obese, but no significant impact on the probability of a child being overweight. © 2010 Taylor & Francis. Source


Peisker H.,University of Kiel | Gorb S.N.,Max Planck Institute for Intelligent Systems (Stuttgart)
Journal of Experimental Biology | Year: 2010

The surface of some insect eyes consists of arrays of cuticular protuberances, which are 50-300 nm in diameter, and are termed corneal nipples or ommatidia gratings. They were widely reported to reduce the reflectance for normally incident light, contributing to camouflage by reducing glare to predators, while furthermore enhancing the intake of light, which is especially important for nocturnal insects. Our preliminary observations suggest a third function: in contrast to the rest of the body, ommatidia of various insects remain clean, even in a heavy contaminated environment. In order to prove such an anticontamination hypothesis of these structures, we measured the adhesive properties of polymer moulds of insect ommatidia, and compared these data with control surfaces having the same curvature radii but lacking such a nanostructure. A scanning electron microscope (SEM) study and force measurements using an atomic force microscope (AFM) on the eye surfaces of three different insect species, dragonfly Aeshna mixta (Odonata), moth Laothoe populi (Lepidoptera) and fly Volucella pellucens (Diptera), were undertaken. We revealed that adhesion is greatly reduced by corneal grating in L. populi and V. pellucens when compared with their smooth controls. The smooth cornea of A. mixta showed no statistically significant difference to its control. We assume that this anti-adhesive phenomenon is due to a decrease in the real contact area between contaminating particles and the eye's surface. Such a combination of three functions in one nanostructure can be interesting for the development of industrial multifunctional surfaces capable of enhancing light harvesting while reducing light reflection and adhesion. © 2010. Published by The Company of Biologists Ltd. Source


Dannehl J.,Danfoss A/S | Liserre M.,Polytechnic of Bari | Fuchs F.W.,University of Kiel
IEEE Transactions on Industrial Electronics | Year: 2011

Pulsewidth modulation (PWM) voltage source converters are becoming a popular interface to the power grid for many applications. Hence, issues related to the reduction of PWM harmonics injection in the power grid are becoming more relevant. The use of high-order filters like LCL filters is a standard solution to provide the proper attenuation of PWM carrier and sideband voltage harmonics. However, those grid filters introduce potentially unstable dynamics that should be properly damped either passively or actively. The second solution suffers from control and system complexity (a high number of sensors and a high-order controller), even if it is more attractive due to the absence of losses in the damping resistors and due to its flexibility. An interesting and straightforward active damping solution consists in plugging in, in cascade to the main controller, a filter that should damp the unstable dynamics. No more sensors are needed, but there are open issues such as preserving the bandwidth, robustness, and limited complexity. This paper provides a systematic approach to the design of filter-based active damping methods. The tuning procedures, performance, robustness, and limitations of the different solutions are discussed with theoretical analysis, selected simulation, and experimental results. © 2009 IEEE. Source


Bruckner S.,TU Dresden | Arlt A.,University of Kiel | Hampe J.,TU Dresden
Endoscopy | Year: 2015

Endoscopic ultrasound-guided biliary drainage (EUS-BD) might be an alternative to percutaneous or transpapillary biliary drainage in unresectable pancreatic or biliary cancer. A lumen-apposing, fully covered, self-expanding metal stent, which creates a sealed transluminal conduit between the biliary and gastrointestinal tract may offer advantages over conventional plastic and metal stents. In this retrospective, observational, open-label case study, five patients underwent EUS-BD for obstructive jaundice in pancreatic cancer (n = 4) or distal cholangiocarcinoma (n = 1). Technical and functional success was achieved in all patients without complications. The development of specialized stent and delivery systems may render EUS-BD an effective and safe alternative to percutaneous or transpapillary approaches. © Georg Thieme Verlag KG Stuttgart. Source


Schauer R.,University of Kiel | Kamerling J.P.,University Utrecht
ChemBioChem | Year: 2011

trans-Sialidases constitute a special group of the sialidase family. They occur in some trypanosome species and, in a unique reversible reaction, transfer sialic acids from one glycosidic linkage with galactose (donor) to another galactose (acceptor), to form (α2-3)-sialyl linkages. Trypanosomes cause such devastating human diseases as Chagas disease in South America (Trypanosoma cruzi) or sleeping sickness in Africa (Trypanosoma brucei). The trans-sialidases strongly contribute to the pathogenicity of the trypanosomes by scavenging sialic acids from the host or blood meal to coat the parasite surface; this aids their survival strategy in the insect's intestine, and in the blood circulation or cells of the host, and serves to compromise the immune system of the human or animal host. American and African trypanosomes express trans-sialidases at different stages of their vector/host development. They are transmitted to humans by insect vectors (tsetse fly or other insect "bug" species). trans-Sialidase activity with varying linkage specificity has also been found in a few bacteria species and in human serum. trans-Sialidases are of increasing practical importance for the chemo-enzymatic synthesis of sialylated glycans. The search for appropriate inhibitors of trans-sialidases and vaccination strategies is intensifying, as less toxic medicaments for the treatment of these widespread and often chronic tropical diseases are required. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Kempken F.,University of Kiel
Molecular Ecology | Year: 2011

Unlike in the laboratory, in nature fungi are exposed to antagonists including competitors, pathogens, parasites and predators. In this issue of Molecular Ecology, an exciting paper by Bleuler-Martínez (2011) has unearthed on one of the processes used by fungi to protect themselves against animal antagonists. The authors from Markus Künzler′s group at the ETH Zürich, Switzerland present direct evidence that filamentous fungi possess an inducible resistance mechanism against predators and parasites. This is based on cytoplasmic lectins, which specifically bind to glycans of these predators and parasites, and thus provide toxicity against them. These lectins are expressed at high levels in fruiting bodies and sclerotia of these fungi (Fig. 1). While there have been previous suggestions and efforts to implicate mycotoxins such as sterigmatocystin into fungal defence mechanisms and as an evolutionary force (see Kempken & Rohlfs 2010), the data presented by Markus Künzler′s group highlight the ecological relevance of lectins in defending fungi from parasites and fungivorous animals. As such this paper provides important ecological clues and suggests that secondary metabolites are not the sole player in fungal-animal competition. It rather appears that fungi have evolved several lines of defence against antagonistic organisms. Fungi protect their fruiting bodies by the use of lectin (picture of Aleuria aurantia provided by Taylor F. Lockwood). © 2011 Blackwell Publishing Ltd. Source


Lithologic interpretations of the earth crust from seismic wave velocities are non-unique so that inferences about composition can not be drawn. In order to evaluate how elastic properties of rock materials are controlled by lithology at in situ pressures and temperatures, compressional (Vp), shear wave velocities (Vs) and velocity anisotropy of crustal rocks were measured at conditions of greater depth. The first part deals with the interdependence of elastic wave propagation and the physical and lithological parameters. In the second part data from laboratory seismic measurements and theoretical calculations are used to interpret (1) a shallow seismic reflection line (SE Finland) and (2) a refraction profile of a deep crust (Central China). The comparison of the calculated velocities with the experimentally-derived in situ velocities of the Finnish crustal rocks give hints that microcracks have an important bearing on the in situ seismic velocities, velocity anisotropy and the reflectivity observed at relative shallow depth. The coupling of the experimentally-derived in situ velocities of P- and S-wave and corresponding Poisson's ratios of relevant exhumed high-grade metamorphic crustal rocks from Central China with respective data from seismic refraction profiling provided a key for the lithologic interpretation of a deep seismic crustal structure. © 2011 Hartmut Kern. Source


To identify lifestyle clusters in adolescents and to characterize their association with overweight and obesity. Cross-sectional and longitudinal data of the Kiel Obesity Prevention Study. Schools in Kiel, Germany. Cross-sectional data of 1894 adolescents aged 14 years and 4-year longitudinal data of a subsample of 389 children aged 10 and 14 years. Self-reported data of physical activity, modes of commuting to school, media time, nutrition, alcohol consumption and smoking were used to identify lifestyle clusters with two-step cluster analysis. Obesity indices (height, weight, waist circumference and fat mass (FM)) were measured. Three lifestyle clusters were identified: a 'low activity and low-risk behaviour' cluster (cluster 1: n 740, 39·1 %); a 'high media time and high-risk behaviour' cluster (cluster 2: n 498, 26·3 %); and a 'high activity and medium-risk behaviour' cluster (cluster 3: n 656, 34·6 %). Strictly speaking, none of these clusters was considered to be markedly healthy. The prevalence of overweight and obesity tended to be lower in cluster 3 (15·9 %) than in clusters 1 (20·4 %) and 2 (20·5 %; P = 0·053). Longitudinally, 4-year changes in FM were found to be lowest in cluster 2, but the 4-year incidence rate of obesity was lowest in cluster 3. Explicit healthy lifestyles do not exist, but an active lifestyle reduces the incidence of obesity. In adolescents, health promotion should take into account the diversity of lifestyles and address specific lifestyle clusters. Source


Aiki H.,Japan Agency for Marine - Earth Science and Technology | Greatbatch R.J.,University of Kiel
Journal of Physical Oceanography | Year: 2012

The residual effect of surface gravity waves on mean flows in the upper ocean is investigated using thicknessweighted mean (TWM) theory applied in a vertically Lagrangian and horizontally Eulerian coordinate system. Depth-dependent equations for the conservation of volume, momentum, and energy are derived. These equations allow for (i) finite amplitude fluidmotions, (ii) the horizontal divergence of currents, and (iii) a concise treatment of both kinematic and viscous boundary conditions at the sea surface. Under the assumptions of steady and monochromatic waves and a uniform turbulent viscosity, theTWMmomentumequations are used to illustrate the pressure- and viscosity-induced momentum fluxes through the surface, which are implicit in previous studies of the wave-induced modification of the classical Ekman spiral problem. TheTWMapproach clarifies, in particular, the surface momentum flux associated with the so-called virtual wave stress of Longuet-Higgins. Overall, theTWMframework can be regarded as an alternative to the three-dimensional Lagrangian mean framework of Pierson. Moreover, the TWM framework can be used to include the residual effect of surface waves in large-scale circulation models. In specific models that carry the TWM velocity appropriate for advecting tracers as their velocity variable, the turbulent viscosity term should be modified so that the viscosity acts only on the Eulerian mean velocity. © 2012 American Meteorological Society. Source


Wunsch L.,University of Lubeck | Holterhus P.M.,University of Kiel | Wessel L.,University of Mannheim | Hiort O.,University of Lubeck
BJU International | Year: 2012

OBJECTIVE • To investigate the role of laparoscopy for the early detection of gonadal tumours, with emphasis on gonadal preservation, in patients with 46XY disorders of sex development (DSD). In patients with DSD, gonadectomy is frequently recommended and depending on the age and the molecular diagnosis, an increased gonadal tumour risk exists and undesired hormone effects may arise. However, gonadectomy is irreversible and impacts considerably on body image. It represents an overtreatment for some patients and should be considered after a comprehensive diagnostic evaluation. Laparoscopy is an important technique, because it is able to retrieve small gonads and allows guided biopsies. PATIENTS AND METHODS • We performed laparoscopic assessment of the gonads in 40 patients with various 46XY DSD. • In all, 77 gonads were evaluated, images were analysed and compared with histological findings. • Laparoscopic procedures included gonadectomy, biopsy, laparoscopic orchidolysis or the Fowler-Stephens procedure as well as the removal or splitting of uterine remnants. RESULTS • In all, 19 patients underwent gonadectomy and tumours were discovered in four. • Three patients had only microscopic evidence of tumour, in one the tumour was diagnosed intraoperatively. • In 21 patients, biopsies were taken and the gonads preserved. • Laparoscopic biopsy and gonadopexy was performed in six patients with complete androgen insensitivity syndrome (CAIS). CONCLUSION • Laparoscopy and biopsy detected three microscopic tumours, one tumour was macroscopically evident. • In CAIS, gonadopexy improved the visibility of the gonads on postoperative ultrasonography. This procedure facilitated the examination of the gonad at follow-up. • In complete gonadal dysgenesis, a highly variable morphology of the gonads was found. Laparoscopy improved exposure of gonads and Müllerian structures, and facilitated biopsies and organ-preserving procedures. © 2012 THE AUTHORS. Source


Kempken F.,University of Kiel
Applied Microbiology and Biotechnology | Year: 2013

Alternative splicing is a complex and regulated process, which results in mRNA with different coding capacities from a single gene. Extend and types of alternative splicing vary greatly among eukaryotes. In this review, I focus on alternative splicing in ascomycetes, which in general have significant lower extend of alternative splicing than mammals. Yeast-like species have low numbers of introns and consequently alternative splicing is lower compared to filamentous fungi. Several examples from single studies as well as from genomic scale analysis are presented, including a survey of alternative splicing in Neurospora crassa. Another focus is regulation by riboswitch RNA and alternative splicing in a heterologous system, along with putative protein factors involved in regulation. © 2013 Springer-Verlag Berlin Heidelberg. Source


Schwanbeck R.,University of Kiel
Journal of Cellular Physiology | Year: 2015

The Notch pathway is a highly conserved cell-cell communication pathway in metazoan involved in numerous processes during embryogenesis, development, and adult organisms. Ligand-receptor interaction of Notch components on adjacent cells facilitates controlled sequential proteolytic cleavage resulting in the nuclear translocation of the intracellular domain of Notch (NICD). There it binds to the Notch effector protein RBP-J, displaces a corepressor complex and enables the induction of target genes by recruitment of coactivators in a cell-context dependent manner. Both, the gene-specific repression and the context dependent activation require an intense communication with the underlying chromatin of the regulatory regions. Since the epigenetic landscape determines the function of the genome, processes like cell fate decision, differentiation, and self-renewal depend on chromatin structure and its remodeling during development. In this review, structural features enabling the Notch pathway to read these epigenetic marks by proteins interacting with RBP-J/Notch will be discussed. Furthermore, mechanisms of the Notch pathway to write and erase chromatin marks like histone acetylation and methylation are depicted as well as ATP-dependent chromatin remodeling during the activation of target genes. An additional fine-tuning of transcriptional regulation upon Notch activation seems to be controlled by the commitment of miRNAs. Since cells within an organism have to react to environmental changes, and developmental and differentiation cues in a proper manner, different signaling pathways have to crosstalk to each other. The chromatin status may represent one major platform to integrate these different pathways including the canonical Notch signaling. J. Cell. Physiol. 230: 969-981, 2015. © 2014 Wiley Periodicals, Inc. Source


Schull G.,CNRS Institute of Genetics and of Molecular and Cellular Biology | Frederiksen T.,Donostia International Physics Center | Arnau A.,Donostia International Physics Center | Arnau A.,University of the Basque Country | And 2 more authors.
Nature Nanotechnology | Year: 2011

The transport of charge through a conducting material depends on the intrinsic ability of the material to conduct current and on the charge injection efficiency at the contacts between the conductor and the electrodes carrying current to and from the material1-3. According to theoretical considerations4, this concept remains valid down to the limit of single-molecule junctions5. Exploring this limit in experiments requires atomic-scale control of the junction geometry. Here we present a method for probing the current through a single C 60 molecule while changing, one by one, the number of atoms in the electrode that are in contact with the molecule. We show quantitatively that the contact geometry has a strong influence on the conductance. We also find a crossover from a regime in which the conductance is limited by charge injection at the contact to a regime in which the conductance is limited by scattering at the molecule. Thus, the concepts of 'good' and 'bad' contacts, commonly used in macro- and mesoscopic physics, can also be applied at the molecular scale. © 2011 Macmillan Publishers Limited. All rights reserved. Source


Egert S.,University of Bonn | Rimbach G.,University of Kiel
Advances in Nutrition | Year: 2011

There is increasing interest in the potential health benefits of dietary flavonoids. Fruits and vegetables, tea, and cocoa are rich natural sources of flavonoids. Epidemiological studies have indicated that consumption of these foods is likely to be associated with a reduced risk of cardiovascular disease, but the etiology of this benefit is not yet clearly defined. Furthermore, in some acute interventions, a positive effect of tea and cocoa on vascular function has been reported. An alternative source of flavonoids is dietary supplements, which have become increasingly popular in the recent past. In this context, it needs to be critically evaluated whether vascular health-promoting and other positive properties of flavonoid-rich diets can be replaced by purified flavonoids as dietary supplements. Plant sources of flavonoids contain a complex mixture of secondary plant metabolites and not only flavonoids per se. This complex mixture of secondary plant metabolites cannot be simply exchanged by single purified compounds as dietary supplements. If flavonoids are given as dietary supplements, toxicity issues as well as nutrient drug interactions need to be taken into account. Purified flavonoids given in high doses as dietary supplements may affect trace element, folate, and vitamin C status. Furthermore, they may exhibit antithyroid and goitrogenic activities. In this review article, the available literature on the safety issues surrounding high dose supplemental flavonoid consumption has been summarized. © 2011 American Society for Nutrition. Source


Dalhoff A.A.H.,University of Kiel | Levy S.B.,Tufts University
International Journal of Antimicrobial Agents | Year: 2015

Natamycin is a poorly soluble, polyene macrolide antifungal agent used in the food industry for the surface treatment of cheese and sausages. This use is not of safety concern. However, highly soluble natamycin-cyclodextrin inclusion complexes have been developed for the protection of beverages. This practice leads to high drug exposures exceeding the safety level. Apart from the definition of an acceptable daily dietary exposure to natamycin, its effect on the faecal flora as a reservoir for resistance has to be examined. Consumption of food to which natamycin has been added and mixed homogeneously, such as yoghurt, and in particular the addition of cyclodextrin inclusion complexes to beverages and wine generates high faecal natamycin concentrations resulting in high drug exposures of faecal Candida spp. Development of natamycin resistance has been observed in Candida spp. colonising the intestinal tract of patients following natamycin treatment of fungal infections. Horizontal gene transfer among different Candida spp. and within Aspergillus fumigatus spreads resistance. Therefore, it cannot be denied that use of natamycin for preservation of yoghurt and beverages may foster development of resistance to polyenes in Candida spp. © 2015 The Authors. Published by Elsevier B.V. on behalf of International Society of Chemotherapy. Source


Multiferroic composite magnetoelectric (ME) sensors are based on the elastic coupling of a magnetostrictive phase and a piezoelectric phase. A deformation of the magnetostrictive phase causes strain in the piezoelectric phase and thus an induced voltage. Such sensors may be applied both for static as well as for dynamic magnetic fieldmeasurements. Particularly high sensitivities are achieved for operation at a mechanical resonance. Here, the resonance line shape of layered (2-2 composite) cantilever ME sensors at the first bending-mode resonance is investigated theoretically. Finite element method (FEM) simulations using a linear material model reveal an asymmetric resonance profile and a zero-response frequency for the ME coefficient. Frequency-dependent strain and electric potential distributions inside the magnetoelectric composite are studied for the case of a magnetostrictive- piezoelectric bilayer. It is demonstrated that a positive or a negative voltage may be induced across the piezoelectric layer depending on the position of the neutral plane. The frequency-dependent induced electric potential is investigated for structured cantilevers that exhibit magnetostriction only at specific positions. For static operation an induced voltage is obtained locally at positions with magnetostriction. In addition to this direct effect a resonance-assisted effect is observed for dynamic operation. Magnetostriction in a limited area of the cantilever causes a global vibration of the cantilever. Thus, deformation of the piezoelectric layer and an induced electric potential also occur in areas of the cantilever without magnetostriction. The direct and the resonance-assisted pathway may induce voltages of equal or of opposite sign. The net induced voltage results from the superposition of the two effects. As the resonance-assisted induced voltage changes sign upon passing the resonance frequency, while the direct component is constant, an asymmetric line shape and a zero-response frequency result for the ME coefficient. The zero-response oscillator frequency may be below or above the resonance frequency. The calculated FEM resonance line shapes are fitted successfully to a superposition function of a constant component and a resonant component with a Lorentzian line shape. Equivalence of the superposition function line shape to a Fano resonance profile is derived for frequencies around the resonance. Fano resonances are ubiquitous in physics occurring due to the constructive and destructive quantum interference of two different scattering pathways, e.g., for photons or electrons. The superposition fit parameters describing the resonance line shape are calculated as a function of the cantilever substrate thickness. The inclusion of loss by adjustment of the damping parameter is discussed. The results derived here also are applicable to higher order modes or longitudinal resonance modes. © 2013 Author(s). Source


Hasler M.,University of Kiel
International Journal of Biostatistics | Year: 2013

This article addresses the problem of multiple contrast tests for repeated measures. Three procedures are described and compared by simulations concerning the familywise error type I. The procedure based on sandwich estimators seems to be most robust, except for all-pair comparisons. © 2013 Elsevier BV. Source


This review summarizes evidence that commercially available fluoroquinolones used for the treatment of bacterial infections are active against other non-bacterial infectious agents as well. Any of these fluoroquinolones exerts, in parallel to its antibacterial action, antiviral, antifungal, and antiparasitic actions at clinically achievable concentrations. This broad range of anti-infective activities is due to one common mode of action, i.e., the inhibition of type II topoisomerases or inhibition of viral helicases, thus maintaining the selective toxicity of fluoroquinolones inhibiting microbial topoisomerases at low concentrations but mammalian topoisomerases at much higher concentrations. Evidence suggests that standard doses of the fluoroquinolones studied are clinically effective against viral and parasitic infections, whereas higher doses administered topically were active against Candida spp. causing ophthalmological infections. Well-designed clinical studies should be performed to substantiate these findings. © 2014, Springer-Verlag Berlin Heidelberg. Source


Kornek T.,University of Kiel | Augustin M.,University of Hamburg
JDDG - Journal of the German Society of Dermatology | Year: 2013

Prevention signifies the avoidance of diseases. It also includes the early detection of diseases and taking measures to avoid worsening of an existing disease. Prevention is divided into primary, secondary and tertiary prevention. The prevention of skin cancer is particularly important due to the rising incidence of skin cancer in recent years. In Germany, 195.000 new cases of skin cancer, including non melanoma skin cancer and melanoma are occurring. Therefore, skin cancer is among the most common cancer diseases. Primary prevention comprises the reduction of skin cancer risk behavior, including education about the danger of UV exposure and the right way of dealing with natural and artificial UV radiation. The implementation of a systematic skin cancer screening in Germany contributes to secondary prevention. First data from the initial project in Schleswig-Holstein, Germanyís most northern state, indicate for the first time that the incidence and mortality of melanoma can be reduced by secondary prevention. For tertiary prevention, the national associations recommend a risk-adapted, evidence-based follow-up for all types of skin cancer. From the perspectives of the payers and from the patients, prevention is assessed positively. Prevention can contribute to a reduction of disease burden. © The Authors • Journal compilation © Blackwell Verlag GmbH, Berlin. Source


Thalheim B.,University of Kiel
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2011

Conceptual modelling is one of the central activities in Computer Science. Conceptual models are mainly used as intermediate artifact for system construction. They are schematic descriptions of a system, a theory, or a phenomenon of an origin thus forming a model. A conceptual model is a model enhanced by concepts. The process of conceptual modelling is ruled by the purpose of modelling and the models. It is based on a number of modelling acts, on a number of correctness conditions, on modelling principles and postulates, and on paradigms of the background or substance theories. Purposes determine the (surplus) value of a model. Conceptual modelling is performed by a modeller that directs the process based on his/her experience, education, understanding, intention and attitude. Conceptual models are products that are used by other stakeholders such as programmers, learners, business users, and evaluators. Conceptual models use a language as a carrier for the modelling artifact and are restricted by the expressiveness of this carrier. This paper aims at a discussion of a general theory of modelling as a culture and an art. A general theory of modelling also considers modelling as an apprenticeship and as a technology. It is thus an art. Modelling is on of the main elements of Computer Science culture that consists of commonly accepted behaviour patterns, arts, consensus, institutions, and all other supporting means and thoughts. © 2011 Springer-Verlag Berlin Heidelberg. Source


Mathiak M.,University of Kiel
Applied Immunohistochemistry and Molecular Morphology | Year: 2015

Microsatellite instable gastric cancer (MSI-GC) is a specific molecular subtype of GC. We studied the phenotypes, genotypes, and clinicopathologic characteristics of MSI-GC in a white GC cohort and compared our findings with an extended literature review. The study cohort consisted of 482 patients. Specimens were available from 452 cases and were used for immunostaining (MLH1, PMS2, MSH2, MSH6) and molecular biological analyses (BAT-25, BAT-26, NR-21, NR-24, NR-27; Epstein-Barr virus in situ hybridization). Thirty-four (7.5%) GCs were MSI. Loss of MLH1 and/or PMS2 was found in 30 (88%) MSI-GC, 3 (9%) showed loss of MSH2 and/or MSH6. One (3%) MSI-GC was identified only by molecular biological testing. A single case was heterogeneous and contained microsatellite-stable and instable tumor areas. Twenty-one (62%) MSI-GCs showed unusual histologic features. MSI-GC was not found in diffuse-type or Epstein-Barr virus-positive GC. MSI-GC was significantly more prevalent in elderly patients, distal stomach, and was associated with a significantly lower number of lymph node metastases and a significantly better overall and tumor-specific survival. MSI-GC constitutes a small but relevant subgroup of GC with distinct clinicopathologic characteristics. Our literature review illustrates the shortcomings of missing standardized testing algorithms with prevalences of MSI-GC ranging from 0% to 44.5%. Future studies should test the hypothesis that patients with MSI-GCs may not need adjuvant/perioperative chemotherapy. However, this will require a standardized, quality-controlled diagnostic algorithm of MSI for GC.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially. http://creativecommons.org/licenses/by-nc-nd/4.0/. Copyright 2015 Wolters Kluwer Health, Inc. All rights reserved. Source


Berghe T.V.,Vlaams Institute for Biotechnology | Linkermann A.,University of Kiel | Jouan-Lanhouet S.,Vlaams Institute for Biotechnology | Walczak H.,University College London | Vandenabeele P.,Vlaams Institute for Biotechnology
Nature Reviews Molecular Cell Biology | Year: 2014

Cell death research was revitalized by the understanding that necrosis can occur in a highly regulated and genetically controlled manner. Although RIPK1 (receptor-interacting protein kinase 1)-and RIPK3-MLKL (mixed lineage kinase domain-like)-mediated necroptosis is the most understood form of regulated necrosis, other examples of this process are emerging, including cell death mechanisms known as parthanatos, oxytosis, ferroptosis, NETosis, pyronecrosis and pyroptosis. Elucidating how these pathways of regulated necrosis are interconnected at the molecular level should enable this process to be therapeutically targeted. © 2014 Macmillan Publishers Limited. Source


Schneider S.A.,Ludwig Maximilians University of Munich | Schneider S.A.,University of Kiel
Current Neurology and Neuroscience Reports | Year: 2016

Syndromes with neurodegeneration with brain iron accumulation (NBIA) are a group of neurodegenerative disorders characterized by abnormalities in brain iron metabolism with excess iron accumulation in the globus pallidus and to a lesser degree in the substantia nigra and sometimes adjacent areas. They clinically present as neurodegenerative diseases with progressive hypo- and/or hyperkinetic movement disorders and a variable degree of pyramidal, cerebellar, peripheral nerve, autonomic, cognitive and psychiatric involvement, and visual dysfunction. Several causative genes underlying NBIA have been identified which explain about 65 % of cases. Pathophysiologically, many of the NBIA syndromes map into related biochemical pathways and gene networks including mitochondrial pathways, lipid metabolism, and autophagy. Treatment for NBIA disorders remains symptomatic but a placebo-controlled double-blind study is underway. Rapid developments prompted the review of this interesting field. © 2016, Springer Science+Business Media New York. Source


Alban S.,University of Kiel
Handbook of experimental pharmacology | Year: 2012

All the adverse effects of heparins are related to their wide variety of biological activities, with bleeding being the most important safety issue, resulting directly from the potency of heparin as an anticoagulant. However, it is hard to define the bleeding risk, since it depends on numerous parameters including the indication, dosage, method, and duration of heparin application, the clinical study design and definition of bleeding as well as patient characteristics and determinants of bleeding such as type of surgery and co-medication. Nonbleeding complications of heparins are caused by binding of heparin molecules to proteins other than antithrombin and to cells, which is generally more pronounced with unfractionated heparin than with low-molecular-weight heparins. Accordingly, heparin-induced thrombocytopenia, the most severe nonbleeding adverse reaction, occurs about 10 times less with low-molecular-weight heparins than with unfractionated heparin. Frequent and therefore important adverse reactions of heparins are skin lesions resulting from delayed-type hypersensitivity reactions. All the other undesirable effects are discussed as well, but they are mostly clinically irrelevant. Source


Xu S.,University of California at Los Angeles | Jura M.,University of California at Los Angeles | Koester D.,University of Kiel | Klein B.,University of California at Los Angeles | Zuckerman B.,University of California at Los Angeles
Astrophysical Journal | Year: 2014

We report Keck/HIRES and Hubble Space Telescope/COS spectroscopic studies of extrasolar rocky planetesimals accreted onto two hydrogen atmosphere white dwarfs, G29-38 and GD 133. In G29-38, eight elements are detected, including C, O, Mg, Si, Ca, Ti, Cr, and Fe while in GD 133, O, Si, Ca, and marginally Mg are seen. These two extrasolar planetesimals show a pattern of refractory enhancement and volatile depletion. For G29-38, the observed composition can be best interpreted as a blend of a chondritic object with some refractory-rich material, a result from post-nebular processing. Water is very depleted in the parent body accreted onto G29-38, based on the derived oxygen abundance. The inferred total mass accretion rate in GD 133 is the lowest of all known dusty white dwarfs, possibly due to non-steady state accretion. We continue to find that a variety of extrasolar planetesimals all resemble to zeroth order the elemental composition of bulk Earth. © 2014. The American Astronomical Society. All rights reserved. Source


Klaus S.,Goethe University Frankfurt | Brandis D.,University of Kiel
Zoological Journal of the Linnean Society | Year: 2011

We investigated sperm cells and spermatophores of four species of Old World freshwater crabs belonging to three different genera of the subfamily Potaminae (family Potamidae). Characters previously believed to be apomorphic for the potamid subfamily Potamiscinae were also found to occur in the Potaminae. To infer the morphological ancestral character state combination of the Potamidae, ancestral character state analysis of four different sperm traits was performed, based on a 16S rDNA phylogeny of the investigated species. Comparing molecular phylogeny and character state distribution, several cases of convergent evolution could be identified. The densely packed, coenospermic spermatophores and the occurrence of a 'tongue-and-groove' connection between operculum and acrosomal zones are probably apomorphies for the whole Potamidae. The spermatozoa of Socotrapotamon socotrense show several unique characters. We also analysed the evolution of acrosome size. The sperm cells of the Potamidae and their sister-group Gecarcinucidae only slightly overlap in acrosome size. Within the investigated species, the 'East Asia' subclade (subfamily Potamiscinae) developed significantly larger acrosomes than the subfamily Potaminae. Our results suggest that the use of brachyuran acrosome morphology for phylogenetic inference at the family level is strongly affected by small sample size, and by convergent character evolution.© 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010. © 2010 The Linnean Society of London. Source


Marsch E.,University of Kiel
Symmetry | Year: 2013

In this paper, we suggest an alternative strategy to derive the complex two-component Majorana equation with a mass term and elucidate the related Lorentz transformation. The Majorana equation is established completely on its own, rather than derived from the chiral Dirac equation. Thereby, use is made of the complex conjugation operator and Pauli spin matrices only. The eigenfunctions of the two-component complex Majorana equation are also calculated. The associated quantum fields are found to describe particles and antiparticles, which have opposite mean helicities and are not their own antiparticles, but correspond to two independent degrees of freedom. The four-component real Dirac equation in its Majorana representation is shown to be the natural outcome of the two-component complex Majorana equation. Both types of equations come in two forms, which correspond to the irreducible left- and right-chiral representations of the Lorentz group. © 2013 by the author; licensee MDPI, Basel, Switzerland. Source


Dombrowski E.,University of Kiel
Phonetica | Year: 2014

This study analyses the meaning spaces of German pitch contours using two modes of melodic movement: continuous or in steps of sustained pitch. Both the continuous and stepped movements are represented by a set of five basic patterns, the latter being derived from the former. Thirty-six German native speakers judged the pattern sets on a 12-scale semantic differential. The semantic profiles confirm that stepped contours can be conceived of as stylized intonation, in a formal as well as in a functional sense. On the one hand, continuous (non-stylized) and stepped (stylized) contours are assigned different overall meanings (especially on the scales astonished-commonplace and interested-not interested). On the other hand, listeners organize the two contour sets in a similar fashion, which speaks in favour of parallel pattern inventories of continuous and stepped movement, respectively. However, the meaning space of the stylized patterns is affected by formal restrictions, for instance in the step transformation of continuous rises. © 2014 S. Karger AG, Basel. Source


Nguyen V.D.,University of Kiel
Communications in Computer and Information Science | Year: 2012

The number of piracy attacks on cargo ships has increased significantly over the past years. Countermeasures often rely on early threat detection. Hence it must be possible to track small targets such as pirates' skiffs. Navigation radar systems for cargo ships are not designed to do so. Advanced radar tracking systems may be capable of small-target tracking but may lack in affordability for ship owners. Thus, a software-based extension is more cost efficient. In this paper an overview of algorithms for detection and automatic tracking of small targets using a navigation radar is presented, and all sufficient steps to process raw radar video up to final tracks are given. Detection and tracking is carried out by Constant-False-Alarm-Rate and Multi-Hypothesis Tracking approaches, respectively. The way of implementing these methods given here ensures long-range tracking of small objects. Tracking results are obtained by applying the methods to a real radar dataset. © 2012 Springer-Verlag. Source


Heyland D.,Angada 4 | Muscedere J.,Angada 4 | Wischmeyer P.E.,Aurora University | Cook D.,St. Josephs Healthcare | And 5 more authors.
New England Journal of Medicine | Year: 2013

BACKGROUND: Critically ill patients have considerable oxidative stress. Glutamine and antioxidant supplementation may offer therapeutic benefit, although current data are conflicting. METHODS: In this blinded 2-by-2 factorial trial, we randomly assigned 1223 critically ill adults in 40 intensive care units (ICUs) in Canada, the United States, and Europe who had multiorgan failure and were receiving mechanical ventilation to receive supplements of glutamine, antioxidants, both, or placebo. Supplements were started within 24 hours after admission to the ICU and were provided both intravenously and enterally. The primary outcome was 28-day mortality. Because of the interim-analysis plan, a P value of less than 0.044 at the final analysis was considered to indicate statistical significance. RESULTS: There was a trend toward increased mortality at 28 days among patients who received glutamine as compared with those who did not receive glutamine (32.4% vs. 27.2%; adjusted odds ratio, 1.28; 95% confidence interval [CI], 1.00 to 1.64; P = 0.05). In-hospital mortality and mortality at 6 months were significantly higher among those who received glutamine than among those who did not. Glutamine had no effect on rates of organ failure or infectious complications. Antioxidants had no effect on 28-day mortality (30.8%, vs. 28.8% with no antioxidants; adjusted odds ratio, 1.09; 95% CI, 0.86 to 1.40; P = 0.48) or any other secondary end point. There were no differences among the groups with respect to serious adverse events (P = 0.83). CONCLUSIONS: Early provision of glutamine or antioxidants did not improve clinical outcomes, and glutamine was associated with an increase in mortality among critically ill patients with multiorgan failure. (Funded by the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00133978.) Copyright © 2013 Massachusetts Medical Society. Source


Widmoser P.,University of Kiel
Agricultural Water Management | Year: 2010

Canopy temperature, which may be estimated by infrared thermometry (IRT), can serve as an indicator of plant water status. Idso et al. (1981a, 1986) proposed the nowadays much used concept of the crop water stress index, which relates observed canopy surface temperature (Ts) to maxima and minima temperature bounds. Jackson et al. (1981) defined those bounds on the basis of the energy balance. Those bounds vary with the meteorological situation. In this paper a chart is offered for general use with a fixed frame for the upper and lower bound. It relates canopy surface temperatures with r1(=1 + rc/ra)-values (rc the canopy resistance and ra the aerodynamic resistance) as a function of a specifically defined temperature sum (S). It links the curved lower bound with the straight upper bound by a bundle of r1-curves (the Ts-S-r1-chart). The lower bound can be expressed by an equation, which approximates the energy balance solution with high accuracy. The sensitivity of the upper bound is also discussed. A comparison was made between bounds following Jackson et al. (1981) and the proposed alternative method, which, however, is limited by the short data-set available for this paper. © 2009 Elsevier B.V. All rights reserved. Source


Braun S.,Kiel Institute for The World Economy | Schmidt U.,University of Kiel | Schmidt U.,University of Johannesburg
Current Biology | Year: 2015

A well-known bias in subjective perceptions of chance is the gambler's fallacy: people typically believe that a streak generated by a series of independent random draws, such as a coin toss, becomes increasingly more likely to break when the streak becomes longer [1]. In a fascinating study, Misirlisoy and Haggard [2] analysed sequential behavior of kickers and goalkeepers in penalty shootouts. They report that goalkeepers are prone to the gambler's fallacy: after a series of three kicks in the same direction, goalkeepers are more likely to dive in the opposite direction at the next kick. Here we argue, first, that a binomial test is more appropriate for testing gambler's fallacy than the tests employed by Misirlisoy and Haggard [2], and second, that penalty shootouts may not be well-suited to analyze the gambler's fallacy. Using a binomial test, we neither find statistically significant evidence for gambler's fallacy in Misirlisoy and Haggard's [2] original data, nor in extended data, nor in data from an idealised laboratory experiment that we ran to address the second point. In line with Misirlisoy and Haggard's [2] original result, we do, however, find evidence for a systematic pattern of goalkeeper's behavior that kickers could exploit. © 2015 Elsevier Ltd. All rights reserved. Source


Piel A.,University of Kiel
Physics of Plasmas | Year: 2011

The role of ion drag forces for the alignment of dust particles is studied for subsonic flows. While alignment by wake-field attraction is a well known mechanism for supersonic flows, it is argued here that ion-scattering forces become more important in subsonic ion flows. A model of non-overlapping collisions is introduced and numerical results are discussed. For typical conditions of dusty plasma experiments, alignment by drag forces is found strong enough to overcome the destabilizing force from Coulomb repulsion between dust particles. It turns out that the major contribution to the horizontal restoring force originates from the transverse momentum transfer, which is usually neglected in ion drag force calculations because of an assumed rotational symmetry of the flow. © 2011 American Institute of Physics. Source


Gelin M.F.,TU Munich | Egorova D.,University of Kiel | Domcke W.,TU Munich
Journal of Physical Chemistry Letters | Year: 2011

We propose a new time-domain spectroscopic technique that is based on strong pump and probe pulses. The strong-pump strong-probe (SPSP) technique provides temporal resolution that is not limited by the durations of the pump and probe pulses. By numerically exact simulations of SPSP signals for a multilevel vibronic model, we show that the SPSP signals exhibit electronic and vibrational beatings on time scales which are significantly shorter than the pulse durations. This suggests the possible application of SPSP spectroscopy for the real-time investigation of molecular processes that cannot be temporally resolved by pump-probe spectroscopy with weak pump and probe pulses. © 2011 American Chemical Society. Source


Froese R.,Leibniz Institute of Marine Science | Quaas M.,University of Kiel
Marine Policy | Year: 2013

At the Rio+20 meeting in June 2012, governments of the world committed to rebuilding fish stock sizes by 2015 at least to levels that can produce the maximum sustainable yield (MSY), even if that would require the temporary closure of fisheries. This study explores the outcomes of such action for European stocks. In 2012, only 8 of 48 stocks (17%) were abundant enough to produce MSY and with a business as usual scenario, this number would not increase by 2015. In contrast, if fishing was reduced to levels consistent with rebuilding and if some fisheries were temporarily closed, 50-70% of the examined stocks would be able to reach the Rio+20 target by the end of 2015. In this scenario, after three years with reduced catches, fish supply from European stocks would reach and exceed the levels of 2011 already in 2016. The implications for fish, fishers and fish consumers are discussed. © 2012 Elsevier Ltd. Source


Waetzig G.H.,CONARIS Research Institute AG | Rose-John S.,University of Kiel
Expert Opinion on Therapeutic Targets | Year: 2012

Introduction: Interleukin-6 (IL-6) is a key target in inflammation and cancer. Selective inhibition of IL-6 trans-signalling could provide the same or even higher therapeutic efficacy with a better side effect profile than complete IL-6 inhibition. Animal studies with IL-6 inhibitors show that the classic IL-6 signalling pathway via the membrane-bound IL-6 receptor (IL-6R) has important physiological functions, whereas blocking the trans-signalling pathway via the soluble IL-6R (sIL-6R) is sufficient to prevent or treat IL-6-driven diseases. Due to the success of the anti-IL-6R antibody tocilizumab and difficulties of constructing selective trans-signalling inhibitors, most drug candidates in clinical development target IL-6 or IL-6R and, thus, both IL-6 pathways. By contrast, the fusion protein sgp130Fc selectively targets IL-6/sIL-6R trans-signalling by utilising the soluble gp130 receptor as the natural inhibitor of trans-signalling. Areas covered: The authors summarise recent developments in the field with a focus on animal studies highlighting the mechanistic differences between classic and trans-signalling and their therapeutic implications. Expert opinion: Characterising disease mechanisms in terms of the employed IL-6 pathways will help to select the right therapeutic IL-6 inhibitor in the future. The trans-signalling inhibitor sgp130Fc is about to enter the clinic and holds promise for a clinically different profile in comparison with complete IL-6 inhibitors. © 2012 Informa UK, Ltd. Source


Gee K.,Forschungszentrum Geesthacht GmbH GKSS | Burkhard B.,University of Kiel
Ecological Complexity | Year: 2010

Although frequently referred to in the literature, the concept of cultural ecosystem services (CES) has so far been limited in its application. Difficulties arise when specifying the nature of intangible values, but more significantly when it comes to relating intangible values to ecosystem functions. After setting out some conceptual issues, this paper uses a case study on the German North Sea coast to illustrate ways of operationalising the concept in a marine context. Based on a survey of local residents, we first identify current CES in the sea and the intangible values associated with them. Seascape and place emerge as useful conceptual bridges linking ecosystem functioning outcomes to key CES values. We then relate this to offshore wind farming, which some residents perceive as a significant threat to certain CES. Although the approach presented increases the visibility of intangible ecosystem values, the problem remains that such assessments are temporal, in need of added calibration and do not automatically put intangibles on a par with market ecosystem value. © 2010 Elsevier B.V. Source


Dreibrodt S.,University of Kiel | Wiethold J.,Institute National Of Recherches Archeologiques Preventives Inrap
Holocene | Year: 2015

The environmental history since the onset of agriculture was reconstructed from sediments and soils in the catchment area of Lake Belau (Schleswig-Holstein, northern Germany). The established chronologies are based on varve counts, radiocarbon data, embedded Icelandic tephra (lake sediments), radiocarbon dates, and embedded artifacts (slope deposits). Neolithic land use triggered small-scale erosion. Lake trophic indicators and pollen data clearly reflect the onset of agriculture and the middle Neolithic expansion of agricultural activity. Despite numerous archaeological findings, less intensive field use and no soil erosion occurred during the older and younger Bronze Age. Perhaps, animal husbandry was more important than cereal cultivation. Between 2000 and 500 cal. bc, Aeolian input from a distant source can be observed. During the late Bronze Age and Pre-Roman Iron Age, intensified field use enabled severe soil erosion (gullies c. 200 cal. bc). The degradation of soils started in this period, influenced by excessive land use, climatic variability, and/or the reduction in Aeolian deposition. The Roman Iron Age and Migration Period were phases of reduced human impact and soil formation. During medieval times, the intensity of field use increased again and another phase of soil erosion (gully in the 14th century, probably reflecting the ‘Magdalenenflut’ 1342) and soil degradation started. After the late medieval crisis caused by the ‘black death’ and several armed conflicts, another increase in soil erosion may reflect the rearrangement of estates (18th−19th century) and introduction of industrial agriculture (20th century). A recurrence of high-intensity erosion events is indicated at c. 1540, 1710, and probably 1939 ad. Whereas the lake trophic status is influenced by human impact on the lake catchment, wetter and warmer climatic phases are reflected in increased carbonate precipitation modulated by solar activity, human impact, and the long-term evolution of vegetation and soils in the lake catchment. © The Author(s) 2014. Source


Berghammer R.,University of Kiel
Journal of Logic and Algebraic Programming | Year: 2013

In social choice theory the Banks set is a well-established choice set for tournaments that consists of the undominated elements of the maximal subtournaments. For non-complete dominance relations J. Duggan proposed three possibilities to modify it. We develop relation-algebraic specifications to compute the Banks set, Duggan's modifications, and variants of them. All these specifications are algorithmic and can directly be translated into the programming language of the computer algebra system RELVIEW. We show that the system is well suited for computing and visualizing the Banks set, its modifications, and the objects to be associated with them. © 2013 Elsevier Inc. All rights reserved. Source


Dalhoff A.,University of Kiel
Interdisciplinary Perspectives on Infectious Diseases | Year: 2012

This paper on the fluoroquinolone resistance epidemiology stratifies the data according to the different prescription patterns by either primary or tertiary caregivers and by indication. Global surveillance studies demonstrate that fluoroquinolone resistance rates increased in the past years in almost all bacterial species except S. pneumoniae and H. influenzae, causing community-acquired respiratory tract infections. However, 10 to 30 of these isolates harbored first-step mutations conferring low level fluoroquinolone resistance. Fluoroquinolone resistance increased in Enterobacteriaceae causing community acquired or healthcare associated urinary tract infections and intraabdominal infections, exceeding 50 in some parts of the world, particularly in Asia. One to two-thirds of Enterobacteriaceae producing extended spectrum β -lactamases were fluoroquinolone resistant too. Furthermore, fluoroquinolones select for methicillin resistance in Staphylococci. Neisseria gonorrhoeae acquired fluoroquinolone resistance rapidly; actual resistance rates are highly variable and can be as high as almost 100, particularly in Asia, whereas resistance rates in Europe and North America range from 10 in rural areas to >30 in established sexual networks. In general, the continued increase in fluoroquinolone resistance affects patient management and necessitates changes in some guidelines, for example, treatment of urinary tract, intra-abdominal, skin and skin structure infections, and traveller's diarrhea, or even precludes the use in indications like sexually transmitted diseases and enteric fever. © 2012 Axel Dalhoff. Source


Bosch T.C.G.,University of Kiel
Gut Microbes | Year: 2012

Any multicellular organism may be considered a metaorganism or holobiont-comprised of the macroscopic host and synergistic interdependence with bacteria, archaea, fungi, viruses and numerous other microbial and eukaryotic species including algal symbionts. Defining the individual microbehost conversations in these consortia is a challenging but necessary step on the path to understanding the function of the associations as a whole. Dissecting the fundamental principles that underlie all host-microbe interactions requires simple animal models with only a few specific bacterial species. Here I present Hydra as such a model with one of the simplest epithelia in the animal kingdom, with the availability of a fully sequenced genome and numerous genomic tools, and with few associated bacterial species. © 2012 Landes Bioscience. Source


Bertram C.,Kiel Institute for The World Economy | Rehdanz K.,Kiel Institute for The World Economy | Rehdanz K.,University of Kiel
Marine Policy | Year: 2013

Marine and coastal ecosystems - and thus the benefits they create for humans - are subject to increasing pressures and competing usages. For this reason, the European Union (EU) adopted the Marine Strategy Framework Directive (MSFD), which is to guide future maritime policy in the EU and aims at achieving or maintaining a good environmental status (GES) of European seas by 2020. To this end, the MSFD requires the development of improvement measures, which have to be assessed inter alia by examining their cost-effectiveness and by carrying out cost-benefit analysis (CBA) before their implementation. This paper investigates the applicability of environmental CBA in the marine context. It identifies and discusses problems that could hamper the environmental effectiveness of the MSFD. For example, the fact that marine ecosystem services are much less tangible than terrestrial ones implies greater challenges for the quantification of benefits for society in a marine context. One finding is that the limitations of environmental valuation methods regarding their ability to capture the whole total economic value of improvement measures are a potential source of problems, as the MSFD allows countries to disregard measures with disproportionately high costs. The trans-boundary nature of the main European seas adds to the complexity of the valuation task, e.g., due to the danger that benefits that occur outside of national territories are neglected. Moreover, the current state of knowledge on the functioning of complex marine ecosystems and the links to socio-economic impacts and human well-being seem insufficient to meet the MSFD requirements. © 2012 Elsevier Ltd. Source


Kern M.,University of Kiel
Dental Materials | Year: 2015

Objectives Despite a huge number of published laboratory bonding studies on dental oxide ceramics clinical long-term studies on resin bonded oxide ceramic restorations are rare. The purpose of this review is to present the best available clinical evidence for successful bonding of dental oxide ceramic restorations. Methods Clinical trials with resin-bonded restorations that had no or only limited mechanical retention and were made from alumina or zirconia ceramic were identified using an electronic search in PubMed database. Overall 10 publications with clinical trials could be identified. Their clinical outcome was compared with that laboratory bond strength studies. Results Clinical data provide strong evidence that air-abrasion at a moderate pressure in combination with using phosphate monomer containing primers and/or luting resins provide long-term durable bonding to glass-infiltrated alumina and zirconia ceramic under the humid and stressful oral conditions. Significance As simple and clinically reliable bonding methods to oxide ceramics exist, the rationale for development of alternative bonding methods might be reconsidered especially when these methods are more time consuming or require rather complicated and/or technique sensitive procedures. © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved. Source


Voget-Kleschin L.,University of Kiel
Journal of Agricultural and Environmental Ethics | Year: 2013

Large-scale land acquisition (LaSLA) in developing countries is discussed controversially in both the media as well as academia: Opponents point to negative social and environmental consequences. By contrast, proponents conceive of LaSLA as much needed investment into the formerly neglected agricultural sector. This contribution aims at analyzing LaSLA's environmental dimension against the background of strong sustainability. To this end, I will first introduce sustainable development as a normative concept based on claims for intra- and intergenerational justice. Subsequently, I will argue in favor of a conception of strong sustainability and employ this conception in developing guidelines for the sustainable handling of natural capital. By outlining the main drivers and consequences of LaSLA, the contribution hopes to demonstrate that proponents conceive of LaSLA as a potential solution to several sustainability problems, notably answering growing worldwide demand for agricultural commodities by increasing agricultural yields, substituting agrofuels for fossil fuels and providing acreage for offsetting carbon emissions. Against this background I argue that if LaSLA causes environmental externalities, it actually increases the problems it is supposed to resolve. Thereby, I develop sustainability criteria in regard to LaSLA's environmental consequences. © 2013 Springer Science+Business Media Dordrecht. Source


Gansicke B.T.,University of Warwick | Koester D.,University of Kiel | Farihi J.,University of Leicester | Girven J.,University of Warwick | And 2 more authors.
Monthly Notices of the Royal Astronomical Society | Year: 2012

We present Hubble Space Telescope (HST) ultraviolet spectroscopy of the white dwarfs PG0843+516, PG1015+161, SDSS1228+1040, and GALEX1931+0117, which accrete circumstellar planetary debris formed from the destruction of asteroids. Combined with optical data, a minimum of five and a maximum of 11 different metals are detected in their photospheres. With metal sinking time-scales of only a few days, these stars are in accretion/diffusion equilibrium, and the photospheric abundances closely reflect those of the circumstellar material. We find C/Si ratios that are consistent with that of the bulk Earth, corroborating the rocky nature of the debris. Their C/O values are also very similar to those of bulk Earth, implying that the planetary debris is dominated by Mg and Fe silicates. The abundances found for the debris at the four white dwarfs show substantial diversity, comparable at least to that seen across different meteorite classes in the Solar system. PG0843+516 exhibits significant overabundances of Fe and Ni, as well as of S and Cr, which suggests the accretion of material that has undergone melting, and possibly differentiation. PG1015+161 stands out by having the lowest Si abundance relative to all other detected elements. The Al/Ca ratio determined for the planetary debris around different white dwarfs is remarkably similar. This is analogous to the nearly constant abundance ratio of these two refractory lithophile elements found among most bodies in the Solar system. Based on the detection of all major elements of the circumstellar debris, we calculate accretion rates of ≃1.7 × 10 8 to ≃1.5 × 10 9gs -1. Finally, we detect additional circumstellar absorption in the Siiv1394, 1403Å doublet in PG0843+516 and SDSS1228+1040, reminiscent to similar high-ionization lines seen in the HST spectra of white dwarfs in cataclysmic variables. We suspect that these lines originate in hot gas close to the white dwarf, well within the sublimation radius. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS. Source


Reck M.,Airway Research Center North | Heigener D.F.,Airway Research Center North | Mok T.,Chinese University of Hong Kong | Soria J.-C.,Institute Gustave Roussy Villejuif | And 3 more authors.
The Lancet | Year: 2013

Non-small-cell lung cancer is one of the leading causes of deaths from cancer worldwide. Therefore, improvements in diagnostics and treatments are urgently needed. In this review, we will discuss the evolution of lung cancer staging towards more non-invasive, endoscopy-based, and image-based methods, and the development of stage-adapted treatment. A special focus will be placed on the role of novel surgical approaches and modern radiotherapy strategies for early stages of disease, the effect of multimodal treatment in locally advanced disease, and ongoing developments in the treatment of patients with metastatic disease. In particular, we will include an emphasis on targeted therapies, which are based on the assumption that a treatable driver mutation or gene rearrangement is present within the tumour. Finally, the position of lung cancer treatment on the pathway to personalised therapy will be discussed. © 2013 Elsevier Ltd. Source


Gruenewald M.,University of Kiel | Ilies C.,Cardiovascular Clinic
Best Practice and Research: Clinical Anaesthesiology | Year: 2013

At present, short-acting drugs are used in order to achieve the three components of anaesthesia, that is, analgesia, hypnosis and immobility. Assessment of the 'analgesia' component in daily clinical routine is, in contrast to the other components, still based on very unspecific clinical 'end' points such as movement, tearing, tachycardia or hypertension. Individually tailored analgesia, however, should enable to maintain an individual nociceptive-anti-nociceptive balance and better avoid these unwanted responses to surgical stimulation. During the last decade, a variety of monitoring systems were developed in order to assess the nociceptive balance. These are, among others, based on the frontal electroencephalography (EEG) and electromyography (EMG) response, evaluation of the autonomic state and autonomic reactions, spinal reflex pathways and calculated drug concentrations. The present review gives an overview on the topic of 'analgesia' monitoring, the available monitoring systems and their clinical evaluation. Most of the systems allow a rapid detection of the nociceptive input; nonetheless, the prediction of an autonomic or somatic response has still to be improved. Several studies reported fewer unwanted events, reduced opioid consumption and shorter emergence from anaesthesia, when opioid administration was based upon monitoring of the nociceptive-anti-nociceptive balance. However, research on the mechanisms of pain processing and for better tools to assess the 'analgesia' component has to continue in order to improve our daily practice. © 2013 Elsevier Ltd. All rights reserved. Source


Heinze S.,University of Kiel | Von Bergmann K.,University of Hamburg | Menzel M.,University of Hamburg | Brede J.,University of Hamburg | And 4 more authors.
Nature Physics | Year: 2011

Skyrmions are topologically protected field configurations with particle-like properties that play an important role in various fields of science. Recently, skyrmions have been observed to be stabilized by an external magnetic field in bulk magnets. Here, we describe a two-dimensional square lattice of skyrmions on the atomic length scale as the magnetic ground state of a hexagonal Fe film of one-atomic-layer thickness on the Ir(111) surface. Using spin-polarized scanning tunnelling microscopy we can directly image this non-collinear spin texture in real space on the atomic scale and demonstrate that it is incommensurate to the underlying atomic lattice. With the aid of first-principles calculations, we develop a spin model on a discrete lattice that identifies the interplay of Heisenberg exchange, the four-spin and the Dzyaloshinskii-Moriya interaction as the microscopic origin of this magnetic state. © 2011 Macmillan Publishers Limited. All rights reserved. Source


Mideksa K.G.,University of Kiel
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference | Year: 2012

The sources of somatosensory evoked potentials (SEPs) and fields (SEFs), which is a standard paradigm, is investigated using multichannel EEG and MEG simultaneous recordings. The hypothesis that SEP & SEF sources are generated in the posterior bank of the central sulcus is tested, and analyses are compared based on EEG only, MEG only, bandpass filtered MEG, and both combined. To locate the sources, the forward problem is first solved by using the boundary-element method for realistic head models and by using a locally-fitted-sphere approach for averaged head models consisting of a set of connected volumes, typically representing the skull, scalp, and brain. The location of each dipole is then estimated using fixed MUSIC and current-density-reconstruction (CDR) algorithms. For both analyses, the results demonstrate that the band-pass filtered MEG can localize the sources accurately at the desired region as compared to only EEG and unfiltered MEG. For CDR analysis, it looks like MEG affects EEG during the combined analyses. The MUSIC algorithm gives better results than CDR, and when comparing the two head models, the averaged and the realistic head models showed the same result. Source


A computer program is presented that can be used to obtain ages of geological significance from compositional data of monazite. The program calculates dates and their errors from U, Th and Pb concentration data obtained with the electron microprobe. The results can be displayed in isochron and gauss curve diagrams. Subsets of the data can be selected and interactively evaluated with a user friendly graphical interface. For each selected data set a cumulative date, an isochron date, their errors and the mean squared weighted deviates (MSWD) are calculated and a chi-square test is performed. The diagrams can be saved to pdf and all calculated data can be exported to a text file or saved in native format. The software runs on any Apple Macintosh with Mac OS X Tiger or later versions. © 2010 Elsevier Ltd. All rights reserved. Source


Karaca D.,University of Kiel | Hensen C.,Leibniz Institute of Marine Science | Wallmann K.,Leibniz Institute of Marine Science
Geochemistry, Geophysics, Geosystems | Year: 2010

Five sediment cores from cold seeps at the forearc off Costa Rica were used to explore the relationship between fluid advection, dissolved Ca concentrations in upward migrating fluids, and authigenic CaCO3 precipitation. A numerical transport-reaction model was used to determine rates of anaerobic oxidation of methane (AOM), CaCO3 precipitation, and benthic fluxes of solutes. Production of carbonate alkalinity and formation of authigenic carbonates is most intense at intermediate flow rates (3-40 cm a -1) and reduced under low and high flux conditions (0.1 and 200 cm a-1). Dissolved Ca concentrations observed in the vent fluids off Costa Rica cover a wide range between 4 and 31 mM, clearly exceeding seawater concentrations at two locations. Systematic model runs showed that high Ca concentrations in ascending fluids enhance the rate of authigenic carbonate production at moderate flow rates leading to an almost quantitative fixation of deeply derived Ca in authigenic carbonates. Hence, CaCO3 precipitation is not only controlled by Ca diffusing into the sediment from bottom water, but also by the Ca concentration in ascending fluids. Thus, Ca enriched fluids offer a reason for enhanced subsurface CaCO3 precipitation and the occurrence of carbonate caps on dewatering structures in the Central American fore-arc. Based on average precipitation rates deduced from the systematic model runs it is possible to give a rough estimate of the global Ca-fixation at cold seeps (∼21010 mol Ca a-1), which suggests that cold seeps are most likely not of key importance with respect to Ca cycling in the ocean. Copyright 2010 by the American Geophysical Union. Source


Lehndorff E.,University of Bonn | Schwark L.,University of Kiel
Atmospheric Environment | Year: 2010

We here report complementary trace element (Fe, Pb, Cd, Zn, Cr, Cu, Ni and sulfur) concentrations and ratios in pine needles collected in the urban area of Cologne, Germany. Potential element sources are discussed in conjunction with enviromagnetic and PAH data to evaluate air quality. Foliar trace element concentrations of Zn, Cr, Cu, Ni and sulfur are close to essential nutrient levels. Median concentrations of foliar Fe, Pb and Cd in Cologne are 132, 1.1, and 0.06μgg-1, respectively. Thus these elements are enhanced over biogenic background levels and show significant accumulation with needle exposure time. Foliar sulfur concentrations vary between 868 and 2076μgg-1 with a median value of 1409μgg-1, except for two locations where 2370 and 2379μgg-1 were observed. Cadmium serves as an indicator for local industrial emissions with short transport distances of only a few kilometres in Cologne City. Elevated Fe, Pb and Zn concentrations mark areas with higher traffic loads and agree with enhanced PAH burdens and magnetic susceptibility intensities of pine needles. Isopleths mapping and source differentiation of atmospheric pollutants using foliar trace elements is feasible. For temporal or spatial high-resolution studies more cost-effective environmental magnetics is recommended, which may guide in design of detailed studies aiming at identification and allocation of emission sources. Hereby, a combination of organic tracers (PAH), magnetic properties, and trace metals is considered most reliable. © 2010 Elsevier Ltd. Source


Dzierma Y.,University of Kiel | Wehrmann H.,SFB 574
Journal of Volcanology and Geothermal Research | Year: 2010

Probabilistic forecasting of volcanic eruptions is a central issue of applied volcanology with regard to mitigating consequences of volcanic hazards. Recent years have seen great advances in the techniques of statistical analysis of volcanic eruption time series, which constitutes an essential component of a multi-discipline volcanic hazard assessment. Here, two of the currently most active volcanoes of South America, Villarrica and Llaima, are subjected to an established statistical procedure, with the aim to provide predictions for the likelihood of future eruptions within a given time interval.In the eruptive history of both Villarrica and Llaima Volcanoes, time independence of eruptions provides consistency with Poissonian behaviour. A moving-average test, helping to assess whether the distribution of repose times between eruptions changes in response to the time interval considered, validates stationarity for at least the younger eruption record. For the earlier time period, stationarity is not entirely confirmed, which may artificially result from incompleteness of the eruption record, but can also reveal fluctuations in the eruptive regime. To take both possibilities into account, several different distribution functions are fit to the eruption time series, and the fits are evaluated for their quality and compared. The exponential, Weibull and log-logistic distributions are shown to fit the repose times sufficiently well. The probability of future eruptions within defined time periods is therefore estimated from all three distribution functions, as well as from a mixture of exponential distribution (MOED) for the different eruption regimes and from a Bayesian approach. Both the MOED and Bayesian estimates intrinsically predict lower eruption probabilities than the exponential distribution function, while the Weibull distributions have increasing hazard rates, hence giving the highest eruption probability forecasts.This study provides one of the first approaches to subject historical time series of small eruptions (including those of Volcanic Explosivity Index = 2) of very active volcanoes to this type of statistical analysis. Since both Villarrica and Llaima are situated in a region of high population density, the eruption probabilities determined in this study present a valuable contribution to regional hazard assessment. © 2010 Elsevier B.V. Source


Approximately 2700 radiocarbon results are currently available from European megalithic contexts. The interpretation of these 14C dates is often difficult. It is not easy to connect many of them from their archaeological context to the construction or the burial phase of the graves. This paper focuses on the megaliths of Scandinavia-a special megalith region-as it is the only place in Europe with 14C dates directly referable to the construction of the passage graves, the graves have good bone preservation, and new dating sequences are available. Some 188 14C results are now available from Scandinavian passage graves. In Sweden, new data suggest that these graves were built from the first half of the 35th century BC onwards. The 14C dates from birch bark as filling material between dry walls make it possible to build a sequence for the construction phase of the passage graves in Denmark from the 33rd century BC onward. With an interpretative Bayesian statistical framework, it is possible to untangle the nuances of the differences for the origin and the spreading of the megaliths in the different regions, to define, together with the archaeological remains, possible cultural-historical processes behind these phenomena and to discuss diffusion versus convergence. © 2010 by the Arizona Board of Regents on behalf of the University of Arizona. Source


Skonhoft A.,Norwegian University of Science and Technology | Vestergaard N.,University of Southern Denmark | Quaas M.,University of Kiel
Environmental and Resource Economics | Year: 2012

An age structured model of a fishery is studied where two fishing fleets, or fishing agents, are targeting two different mature age classes of the fish stock. The agents are using different fishing gear with different fishing selectivity. The model includes young and old mature fish that can be harvested, in addition to an age class of immature fish. The paper describes the optimal harvesting policy under different assumptions on the objectives of the social planner and on fishing selectivity. First, biomass yield is maximized under perfect fishing selectivity, second, equilibrium profit (rent) is maximized under perfect fishing selectivity, and third, equilibrium profit is maximized under imperfect fishing selectivity. The paper provides results that differ significantly from the standard lumped parameter (also surplus production, or biomass) model. © 2011 Springer Science+Business Media B.V. Source


The endangered hot spring snake (Thermophis baileyi) is endemic to the Tibetan Plateau and restricted to a few sites at high altitudes (>3500. m. a.s.l.). Its strong preference for habitats with hot springs might be an early adaptation to the cooling climate during the plateau uplift. Some of these thermal sites may have been free of ice during the last glacial maximum (LGM) serving as refuges for the snake. To test this and to examine the population genetic structure data of 12 microsatellites and mitochondrial DNA were obtained from 153 individuals from 12 sites across the plateau. Four of the microsatellite loci were newly developed for this study. The results suggest that T. baileyi has at least two genetically diverse clades in Tibet, which developed during the Pleistocene and expanded after the LGM. Accordingly, the existence of separate glacial refuges on the central plateau can be assumed. Analyses of the genetic variation indicated a high level of geographic differentiation and population structure on a regional as well as on a range-wide scale. The study shows that, apart from the phylogeographic signatures, the diversification of current Thermophis populations is caused by (a) a limited dispersal due to mountain ranges, (b) a strong preference for hot springs and (c) the insular distribution of suitable habitats on the plateau. The present data should be taken into account in necessary monitoring and management plans for T. baileyi. © 2012 Elsevier Inc. Source


Burkhardt B.,University of Kiel | Burkhardt B.,Justus Liebig University
British Journal of Haematology | Year: 2010

There is ongoing discussion on whether paediatric acute T-cell lymphoblastic leukaemia (T-ALL) and paediatric lymphoblastic T-cell lymphoma (T-LBL) are two distinct entities or whether they represent two variant manifestations of one and the same disease and the distinction is arbitrary. Both show overlapping clinical, morphological and immunophenotypic features. Many clinical trials use the amount of blast infiltration of the bone marrow as the sole criterion to distinguish between T-ALL and T-LBL. The current World Health Organization classification designates both malignancies as T lymphoblastic leukaemia/lymphoma. However, subtle immunophenotypic, molecular and cytogenetic differences suggest that T-ALL and T-LBL might be biologically different in certain aspects. The current review summarizes and discusses the recent advances and understanding of the molecular profile of paediatric T-ALL and T-LBL. © 2009 Blackwell Publishing Ltd. Source


Kiel S.,University of Kiel
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2010

Faunal communities inhabiting hydrocarbon seeps in the deep sea today show a depth-related change in their ecologic structure: the proportion of obligate ('endemic') taxa increases with depth while the abundance of predators and other background taxa decreases. Here the fossil record of seep communities is investigated for similar gradients. The middle Eocene to middle Miocene deep-water cold-seep deposits in western Washington State, USA, are from different depths: those of the middle to late Eocene Humptulips, Bear River and Whiskey Creek sites lived in depths of 500 to 2000. m, those of the late Oligocene to middle Miocene seep communities of the Lincoln Creek and Astoria Formations in depths of 16 to 900. m. These seeps were inhabited by the same taxa that inhabit cold seeps today and like their modern analogs, they show an increasing proportion of obligate taxa and a decreasing abundance of predators and other background taxa with depth. Also among late Mesozoic seep sites a depth-related change in the proportion of obligate taxa is apparent: seep communities in shallow-shelf settings harbor virtually no obligates, while seep communities in outer shelf to slope settings show a high proportion of obligates, although the constituting species have different taxonomic affinities than their Cenozoic and extant counterparts. Unlike in modern examples, differences between seep communities from outer shelf and slope depths were not seen. It is hypothesized that due to the higher Mesozoic sea-levels many seep communities on the continental shelves were located below the photic zone, where an obligate seep fauna could develop. Because an increase in the proportion of obligate taxa with depth can be seen both in the Cenozoic and in the late Mesozoic despite the different taxonomic affinities of the obligate taxa, it is suggested here that this depth-related structure is a general feature of seep faunas independent of the taxa that express this pattern. © 2010 Elsevier B.V. Source


Schroder B.,University of Kiel
Biochimica et Biophysica Acta - Molecular Cell Research | Year: 2016

The invariant chain (CD74) is well known for its essential role in antigen presentation by mediating assembly and subcellular trafficking of the MHCII complex. Beyond this, CD74 has also been implicated in a number of processes independent of MHCII. These include the regulation of endosomal trafficking, cell migration and cellular signalling as surface receptor of the pro-inflammatory cytokine macrophage migration inhibitory factor (MIF). In several forms of cancer, CD74 is up-regulated and associated with enhanced proliferation and metastatic potential. In this review, an overview of the diverse biological functions of the CD74 protein is provided with a particular focus on how these may be regulated. In particular, proteolysis of CD74 will be discussed as a central mechanism to control the actions of this important protein at different levels. © 2016 Elsevier B.V. Source


Gilbert S.F.,Swarthmore College | Gilbert S.F.,University of Helsinki | Bosch T.C.G.,University of Kiel | Ledon-Rettig C.,Indiana University Bloomington
Nature Reviews Genetics | Year: 2015

The integration of research from developmental biology and ecology into evolutionary theory has given rise to a relatively new field, ecological evolutionary developmental biology (Eco-Evo-Devo). This field integrates and organizes concepts such as developmental symbiosis, developmental plasticity, genetic accommodation, extragenic inheritance and niche construction. This Review highlights the roles that developmental symbiosis and developmental plasticity have in evolution. Developmental symbiosis can generate particular organs, can produce selectable genetic variation for the entire animal, can provide mechanisms for reproductive isolation, and may have facilitated evolutionary transitions. Developmental plasticity is crucial for generating novel phenotypes, facilitating evolutionary transitions and altered ecosystem dynamics, and promoting adaptive variation through genetic accommodation and niche construction. In emphasizing such non-genomic mechanisms of selectable and heritable variation, Eco-Evo-Devo presents a new layer of evolutionary synthesis. © 2015 Macmillan Publishers Limited. Source


Ogundari K.,Kyushu University | Abdulai A.,University of Kiel
Food Policy | Year: 2013

Several studies conducted over the past three decades on calorie-income relationship appear to give inconclusive results. This paper reviews these studies and employs meta-regression analysis to examine the potential publication bias in the calorie-income elasticity, as well as the impact of specific study attributes on the elasticities that have been reported in the empirical literature. A total of 40 empirical studies, which yielded 99 estimated elasticities were considered. The results indicate the presence of publication bias in the reported elasticities. Besides, the estimates revealed evidence of positive and significant empirical effect of income on calorie intake from all the studies that goes beyond publication bias. Study attributes such as ranking of the journal, panel data used in the analysis, whether expenditure was used as proxy for income, year of primary survey, sample size, and numbers of the years of primary data were found to have statistically significant impacts on the reported calorie-income elasticities in the literature. © 2013 Elsevier Ltd. Source


Braack M.,University of Kiel | Schieweck F.,Otto Von Guericke University of Magdeburg
Computer Methods in Applied Mechanics and Engineering | Year: 2011

For the Darcy-Brinkman equations, which model porous media flow, we present an equal-order H1-conforming finite element method for approximating velocity and pressure based on a local projection stabilization technique. The method is stable and accurate uniformly with respect to the coefficients of the viscosity and the zeroth order term in the momentum equation. We prove a priori error estimates in a mesh-dependent norm as well as in the L2-norm for velocity and pressure. In particular, we obtain optimal order of convergence in L2 for the pressure in the Darcy case with vanishing viscosity and for the velocity in the general case with a positive viscosity coefficient. Numerical results for different values of the coefficients in the Darcy-Brinkman model are presented which confirm the theoretical results and indicate nearly optimal order also in cases which are not covered by the theory. © 2010 Elsevier B.V. Source


Koester D.,University of Kiel | Gansicke B.T.,University of Warwick | Farihi J.,University College London
Astronomy and Astrophysics | Year: 2014

Context. Heavy metals in the atmospheres of white dwarfs are thought in many cases to be accreted from a circumstellar debris disk, which was formed by the tidal disruption of a rocky planetary body within the Roche radius of the star. The abundance analysis of photospheric elements and conclusions about the chemical composition of the accreted matter are a new and promising method of studying the composition of extrasolar planetary systems. However, ground-based searches for metal-polluted white dwarfs that rely primarily on the detection of the Ca II K line become insensitive at Teff > 15 000 K because this ionization state depopulates. Aims. We present the results of the first unbiased survey for metal pollution among hydrogen-atmosphere (DA type) white dwarfs with cooling ages in the range 20-200 Myr and 17 000 K 23 000 K, in excellent agreement with the absence of infrared excess from dust around these warmer stars. The median, main sequence progenitor of our sample corresponds to an A-type star of ≈ 2 M™, and we find 13 of 23 white dwarfs descending from main sequence 2-3 M™, late B- and A-type stars to be currently accreting. Only one of 14 targets with Mwd> 0.8 M ™ is found to be currently accreting, which suggests a large fraction of these stars result from double-degenerate mergers, and the merger disks do not commonly reform large planetesimals or otherwise pollute the remnant. We reconfirm our previous finding that two 625 Myr Hyades white dwarfs are currently accreting rocky planetary debris. Conclusions. At least 27% of all white dwarfs with cooling ages 20-200 Myr are accreting planetary debris, but that fraction could be as high as ≈50%. At Teff> 23 000 K, the luminosity of white dwarfs is probably sufficient to vaporize circumstellar dust grains, so no stars with strong metal-pollution are found. Planetesimal disruption events should occur in this cooling age and temperature range as well, and they are likely to result in short phases of high mass-transfer rates. It appears that the formation of rocky planetary material is common around 2-3 M™late B- and A-type stars. © ESO, 2014. Source


Von Hoyningen-Huene J.,Alcatel - Lucent | Von Hoyningen-Huene J.,University of Kiel | Ryf R.,Alcatel - Lucent | Winzer P.,Alcatel - Lucent
Optics Express | Year: 2013

Spatial light modulation can be used to address specific fiber modes, as required in mode-division multiplexed systems. We theoretically compare phase-only spatial light modulation to a combination of amplitude and phase spatial light modulation in terms of insertion loss and crosstalk for a fiber supporting 11 LP modes. We experimentally demonstrate selective mode excitation using a Liquid Crystal on Silicon (LCoS) spatial light modulator configured to as phase and amplitude modulator. © 2013 Optical Society of America. Source


Two new species of the genus Tannea Blackwelder from Ecuador, Tannea hermani n. sp. and Tannea bellavistae n. sp. are herein described, and a complete list of records of all Tannea species found in Ecuador is provided together with a key to the species. Additionally, the geographic distribution of the Tannea species of Ecuador and their altitudinal distribution are discussed. © 2012 Sociedade Entomológica do Brasil. Source


Gelin M.F.,TU Munich | Egorova D.,University of Kiel | Domcke W.,TU Munich
Journal of Physical Chemistry B | Year: 2011

We have extended the doorway-window representation of optical pump-probe spectroscopy with weak pulses toward N-wave-mixing spectroscopy with temporally well-separated pulses of arbitrary strength. The expressions for the signals in the strong-pulse doorway-window representation are derived in the framework of the nonperturbative theory of N-wave-mixing spectroscopy. The strong- pulse doorway-window representation is complementary to the equation-of-motion phase-matching approach. The latter fully accounts for pulse-overlap effects in signals induced by weak pulses but is computationally more expensive. The performance of the doorway-window approximation for temporally well-separated strong pulses is illustrated for an electronic two-level system with an underdamped Condon-active vibrational mode. © 2011 American Chemical Society. Source


Loch T.,University of Kiel | Carey B.,St James Institute Of Oncology | Walz J.,Institute Paoli Calmettes Cancer Center | Fulgham P.F.,Texas Health Presbyterian Hospital Dallas
European Urology | Year: 2015

Background The terminology and abbreviations used in urologic imaging have generally been adopted on an ad hoc basis by different speciality groups; however, there is a need for shared nomenclature to facilitate clinical communication and collaborative research. Objective This work reviews the current nomenclature for urologic imaging used in clinical practice and proposes a taxonomy and terminology for urologic imaging studies. Design, setting, and participants A list of terms used in urologic imaging were compiled from guidelines published by the European Association of Urology and the American Urological Association and from the American College of Radiology Appropriateness Criteria. Outcome measurements and statistical analysis Terms searched were grouped into broad categories based on technology, and imaging terms were further stratified based on the anatomic extent, contrast or phases, technique or modifiers, and combinations or fusions. Terms that had a high degree of utilisation were classified as accepted. Results and limitations We propose a new taxonomy to define a more useful and acceptable nomenclature model acceptable to all health professionals involved in urology. The major advantage of a taxonomic approach to the classification of urologic imaging studies is that it provides a flexible framework for classifying the modifications of current imaging modalities and allows the incorporation of new imaging modalities. The adoption of this hierarchical classification model ranging from the most general to the most detailed descriptions should facilitate hierarchical searches of the medical literature using both general and specific terms. This work is limited in its scope, as it is not currently all-inclusive. This will hopefully be addressed by future modification as others embrace the concept and work towards uniformity in nomenclature. Conclusions This paper provides a noncomprehensive list of the most widely used terms across different specialties. This list can be used as the basis for further discussion, development, and enhancement. Patient summary In this paper we describe a classification system for urologic imaging terms with the aim of aiding health professionals and ensuring that the terms used are more consistent. © 2014 European Association of Urology. Published by Elsevier B.V. All rights reserved. Source


Introduction: This review summarizes data on the fluoroquinolone resistance epidemiology published in the previous 5 years. Materials and methods: The data reviewed are stratified according to the different prescription patterns by either primary- or tertiary-care givers and by indication. Global surveillance studies demonstrate that fluoroquinoloneresistance rates increased in the past several years in almost all bacterial species except Staphylococcus pneumoniae and Haemophilus influenzae causing community-acquired respiratory tract infections (CARTIs), as well as Enterobacteriaceae causing community-acquired urinary tract infections. Geographically and quantitatively varying fluoroquinolone resistance rates were recorded among Gram-positive and Gram-negative pathogens causing healthcare-associated respiratory tract infections. One- to two-thirds of Enterobacteriaceae producing extendedspectrum b-lactamases (ESBLs) were fluoroquinolone resistant too, thus, limiting the fluoroquinolone use in the treatment of community- as well as healthcare-acquired urinary tract and intra-abdominal infections. The remaining ESBL-producing or plasmid-mediated quinolone resistance mechanisms harboring Enterobacteriaceae were low-level quinolone resistant. Furthermore, 10-30 % of H. influenzae and S. pneumoniae causing CARTIs harbored first-step quinolone resistance determining region (QRDR) mutations. These mutants pass susceptibility testing unnoticed and are primed to acquire high-level fluoroquinolone regulatory authorities, and the pharmaceutical industry have diverse interests, which, however, are not addressed by different designs of a surveillance study. Tools should be developed to provide customer-specific datasets. Conclusion: Consequently, most surveillance studies suffer from well recognized but uncorrected biases or inaccuracies. Nevertheless, they provide important information that allows the identification of trends in pathogen incidence and antimicrobial resistance. © Springer-Verlag 2011. Source


Fandrich F.,University of Kiel
Langenbeck's Archives of Surgery | Year: 2011

Introduction: The achievement of clinical operational tolerance (COT) is still considered a major goal in the academic field of solid organ transplantation. Even COT is feasible and safe in selected cases after liver transplantation, in the clinical arena of solid organ transplantation, tolerance remains, for the most part, a concept rather than a reality. Challenges: Although modern immunosuppression regimens have effectively handled acute rejection, nearly all organs except the liver commonly suffer chronic immunologic damage that impairs organ function, threatening patient and allograft survival. Strong arguments in favour of conducting clinical tolerance trials are the high number of grafts still lost due to chronic rejection, the burden of serious adverse effects from immunosuppressants which causes considerable cardiovascular morbidity and mortality, respectively, and the fact that sporadic tolerance can be observed in rare cases where non-adherence to immunosuppressive regimens is linked with a state of long-lasting organ tolerance. Whereas molecule-based regimens have been largely ineffective, cell-based tolerance protocols have delivered some encouraging results to achieve COT. Discussion: In combination with donor bone marrow-derived stem cells, some encouraging results in COT development were reported lately for renal transplantation as well. However, less toxic conditioning protocols and more experience by use of cell products with regulatory properties in combination with synergizing immunosuppressive drugs is required to launch future tolerance trials for a broader spectrum of potential transplant candidates. New methods in immunomonitoring including biomarkers, microarray-based genetic tolerance signatures and functional assays may pave the way to achieve COT in upcoming clinical trials. © 2011 Springer-Verlag. Source


Scherzer T.R.,University of Kiel | Ekroll V.,Catholic University of Leuven
Journal of Vision | Year: 2015

In the occlusion illusion, a partly occluded object is perceived as though it were less occluded than it actually is (Palmer, Brooks, & Lai, 2007). We confirm and extend this finding using a stimulus with a moving occluder. In agreement with Palmer et al.'s (2007) findings and their partial-modal-completion hypothesis, we found that the illusion is indeed related to the sensory evidence for occlusion. Our experiments also confirm their speculation that the occlusion illusion involves an intriguing, seemingly paradoxical percept. In our experiments, subjects viewed an opaque disk with an open sector rotating in front of a background and indicated the perceived angular extent (a) of the occluder and (b) of the part of the background experienced as directly visible through the open sector. While the former was judged quite accurately, the latter was clearly overestimated. Thus, the angular extent of the background experienced as occluded and the extent experienced as directly visible sum to more than 360°, which makes the total percept an impossible figure. We argue that the key to resolving this paradox is to question the seemingly self-evident assumption that occluded and unoccluded portions of a visual scene are represented by amodal and modal percepts, respectively. Instead, we propose that visual percepts are experienced as modal whenever they are based on sufficiently conclusive sensory evidence and are otherwise experienced as amodal. Functionally, this perceptual representation of the conclusiveness of the sensory evidence underlying perceptual inferences might be more useful than estimates about optical visibility. © 2015 ARVO. Source


Golz J.,University of Kiel
Perception | Year: 2010

In numerous studies on colour constancy or colour induction subjects have to adjust a test field so that it looks achromatic. Their viewing behaviour during these settings is often not controlled or reported. Here I show that the results of grey settings depend on whether subjects visually explore the stimulus by looking around or fixate their gaze exclusively on the test field. Two different viewing instructions are compared with regard to the degree of constancy as measured by the shift of grey settings in coloured surrounds. In variegated surrounds (but not in uniform surrounds) there is a robust effect of viewing condition for all subjects and all surround chromaticities tested, in that exploration increases colour constancy compared to fixat ing the test field. Values of a colour constancy index are increased by as much as 20% (where 100% colour constancy means that the subject chooses as grey the mean chromaticity of the surround) with an average across all subjects and surrounds of 12.6%. Thus, if this factor is not experimentally controlled, it could inflate variance, reduce comparability between different studies, and even lead to unwarranted conclusions if viewing behaviour unpredictably differs between experimental conditions. Source


Liebs T.R.,University of Kiel | Herzberg W.,Asklepios Westklinikum Hamburg
Clinical Orthopaedics and Related Research | Year: 2013

Background: The number of unicompartmental knee arthroplasties (UKAs) is growing worldwide. Because lateral UKAs are performed much less frequently than medial UKAs, the limited information leaves unclear whether UKAs have comparable survival and health-related quality of life (HRQoL) of the lateral UKA to medial UKAs. Questions/purposes: We therefore compared the (1) survivorship and (2) HRQoL after lateral versus medial cemented mobile-bearing UKAs and (3) determined whether there is an association of survival to modifications of surgical technique in one of three phases. Methods: We retrospectively reviewed 558 patients who underwent mobile-bearing UKAs from 2002 to 2009. From the records we determined revision of the joint for any reason and revision for aseptic loosening. Patients reported their physical function, pain, and stiffness as measured by the WOMAC, SF-36 physical-component summary (PCS), and Lequesne knee score. Information regarding implant survival was collected for 93% of the patients. We analyzed the patients separately by three phases based on surgical changes associated with each phase (1: initial technique; 2: improved cementing; 3: additional bone resection to ensure backward sliding of the inlay without impingement). The minimum followup was 2.1 years (mean, 6 years; range, 2.1-9.8 years). Results: Implant survival was 88% at 9 years. We found similar implant survival rates for medial (90%) and lateral UKAs (83%). In all HRQoL measures, patients receiving a medial UKA had better mean scores compared with patients who had a lateral UKA: WOMAC physical function (23 versus 34, respectively) and pain (21 versus 34) and SF-36 PCS (41 versus 38). There were no survival differences by surgical phase. Conclusions: Our observations suggest a medial UKA is associated with superior HRQoL when compared with a lateral UKA, although implant survival is similar. Level of Evidence: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence. © 2013 The Association of Bone and Joint Surgeons®. Source


Homaeigohar S.,Helmholtz Center Geesthacht | Elbahri M.,Helmholtz Center Geesthacht | Elbahri M.,University of Kiel
Materials | Year: 2014

Rapid worldwide industrialization and population growth is going to lead to an extensive environmental pollution. Therefore, so many people are currently suffering from the water shortage induced by the respective pollution, as well as poor air quality and a huge fund is wasted in the world each year due to the relevant problems. Environmental remediation necessitates implementation of novel materials and technologies, which are cost and energy efficient. Nanomaterials, with their unique chemical and physical properties, are an optimum solution. Accordingly, there is a strong motivation in seeking nano-based approaches for alleviation of environmental problems in an energy efficient, thereby, inexpensive manner. Thanks to a high porosity and surface area presenting an extraordinary permeability (thereby an energy efficiency) and selectivity, respectively, nanofibrous membranes are a desirable candidate. Their functionality and applicability is even promoted when adopting a nanocomposite strategy. In this case, specific nanofillers, such as metal oxides, carbon nanotubes, precious metals, and smart biological agents, are incorporated either during electrospinning or in the post-processing. Moreover, to meet operational requirements, e.g., to enhance mechanical stability, decrease of pressure drop, etc., nanofibrous membranes are backed by a microfibrous non-woven forming a hybrid membrane. The novel generation of nanocomposite/hybrid nanofibrous membranes can perform extraordinarily well in environmental remediation and control. This reality justifies authoring of this review paper. © 2014 by the authors. Source


Previous studies suggest that a low-glycaemic index (LGI) diet may improve insulin sensitivity (IS). As IS has been shown to decrease during refeeding, we hypothesised that an LGI- v. high-GI (HGI) diet might have favourable effects during this phase. In a controlled nutritional intervention study, sixteen healthy men (aged 26·8 (SD 4·1) years, BMI 23·0 (SD 1·7) kg/m2) followed 1 week of overfeeding, 3 weeks of energy restriction and of 2 weeks refeeding at ^50% energy requirement (50% carbohydrates, 35% fat and 15% protein). During refeeding, subjects were divided into two matched groups receiving either high-fibre LGI or lower-fibre HGI foods (GI 40 v. 74, fibre intake 65 (SD 6) v. 27 (SD 4) g/d). Body weight was equally regained in both groups with refeeding (mean regain 70·5 (SD 28·0)% of loss). IS was improved by energy restriction and decreased with refeeding. The decreases in IS were greater in the HGI than in the LGIgroup (group £ time interactions for insulin, homeostasis model assessment of insulin resistance (HOMAIR), Matsuda IS index (MatsudaISI);all P,0·05). Mean interstitial glucose profiles during the day were also higher in the HGI group (DAUCHGI-LGI of continuous interstitial glucose monitoring: 6·6 mmol/l per 14 h, P1/40·04). At the end of refeeding, parameters of IS did not differ from baseline values in either diet group (adiponectin, insulin, HOMAIR, Matsuda ISI, M-value; all P.0·05). In conclusion, nutritional stress imposed by dietary restriction and refeeding reveals a GI/fibre effect in healthy non-obese subjects. LGI foods rich in fibre may improve glucose metabolism during the vulnerable refeeding phase of a weight cycle. Source


Kirleis W.,University of Kiel | Fischer E.,Landesamt For Denkmalpflege Labor For Archaobotanik
Vegetation History and Archaeobotany | Year: 2014

For the first time, rachis fragments of tetraploid free threshing wheat were discovered for the Early Neolithic of the North European Plain, proving its cultivation by farmers of the Neolithic Funnel Beaker North group. A compilation of finds of free threshing wheat for Northern Europe based on a temporal resolution of Funnel Beaker sub-periods shows the importance of free threshing wheat-independent of genomic constitution-in the Early Neolithic Funnel Beaker crop assemblage. Based on this new evidence, we assume that the crop assemblages of the first farmers on the North European Plain consisted of three main cereals: emmer, barley and free threshing wheat. Both the new finds and the compilation of free threshing wheat finds support the scenario of a chronological separation of different agricultural systems that were implemented within different Funnel Beaker phases. Furthermore, the evidence for tetraploid free threshing wheat shows that the tradition of early Funnel Beaker groups is linked to southwestern agricultural developments, for example, of the Michelsberg group. © 2014 Springer-Verlag Berlin Heidelberg. Source


Camphuysen K.C.J.,Netherlands Institute for Sea Research | Shamoun-Baranes J.,University of Amsterdam | Bouten W.,University of Amsterdam | Garthe S.,University of Kiel
Biological Conservation | Year: 2012

The identification of marine areas of importance for seabirds is a challenge, because it is often unclear how birds are using the different areas in which they occur. Species differ in habitat choice, foraging behaviour and feeding range, but also in tendencies to roost at sea or to utilise resting places closer to or even on land. Because the designation of marine protected areas (MPAs) for seabirds should bear relevance to the ecological importance of these regions, simple presence/absence information is not sufficiently accurate and could even be misleading. Large amounts of data have been collected to assess distribution patterns of seabirds around the world. Two sources of data are highlighted here: ship-based surveys and sensor data from instruments attached to individual birds. Recently developed protocols to systematically record seabird behaviour at sea during ship-based surveys and novel tracking technology that facilitate spatio-temporal quantification of space use and identification of behaviour will be evaluated in the context of MPA designations. We present some limitations of traditional techniques and exciting possibilities of new protocols and the latest generations of electronic devices attached to seabirds. These advanced approaches in data collection and spatial analysis will reveal important ecological information that will enhance our understanding of offshore seabird distribution and activity which can guide the designation of marine protected areas. © 2011 Elsevier Ltd. Source


Nedkov S.,Bulgarian Academy of Science | Burkhard B.,University of Kiel
Ecological Indicators | Year: 2012

Floods exert significant pressure on human societies. Assessments of an ecosystem's capacity to regulate and to prevent floods relative to human demands for flood regulating ecosystem services can provide important information for environmental management. In this study, the capacities of different ecosystems to regulate floods were assessed through investigations of water retention functions of the vegetation and soil cover. The use of the catchment based hydrologic model KINEROS and the GIS AGWA tool provided data about peak rivers' flows and the capability of different land cover types to "capture" and regulate some parts of the water. Based on spatial land cover units originating from CORINE and further data sets, these regulating ecosystem services were quantified and mapped. Resulting maps show the ecosystems' flood regulating service capacities in the case study area of the Malki Iskar river basin above the town of Etropole in the northern part of Bulgaria. There, the number of severe flood events causing significant damages in the settlements and infrastructure has been increasing during the last few years. Maps of demands for flood regulating ecosystem services in the study region were compiled based on a digital elevation model, land use information and accessibility data. Finally, the flood regulating ecosystem service supply and demand data were merged in order to produce a map showing regional supply-demand balances. The resulting map of flood regulation supply capacities shows that the Etropole municipality's area has relatively high capacities for flood regulation. Areas of high and very high relevant capacities cover about 34% of the study area. The flood regulation ecosystem service demand map shows that areas of low or no relevant demands far exceed the areas of high and very high demands, which comprise only 0.6% of the municipality's area. According to the flood regulation supply-demand balance map, areas of high relevant demands are located in places of low relevant supply capacities. The results show that the combination of data from different sources with hydrological modeling provides a suitable data base for the assessment of complex function-service-benefit relations. © 2011 Elsevier Ltd. All rights reserved. Source


Kliemann L.,University of Kiel
Algorithmica | Year: 2016

We study the bilateral version of the adversary network formation game introduced by the author in 2010. In bilateral network formation, a link is formed only if both endpoints agree on it and then both have to pay the link cost (Formula presented.) for it. In the adversary model, the cost of each player comprises this building cost plus the expected number of other players to which she will lose connection if one link is destroyed randomly according to a known probability distribution. Two adversaries are considered: one chooses the link to destroy uniformly at random from the set of all built links, the other instead concentrates the probability measure on the built links which cause a maximum number of player pairs to be separated when destroyed. Pairwise stability (PS) and pairwise Nash equilibrium (PNE) are used as equilibrium concepts. For the first adversary, we prove convexity of cost, hence PS and PNE coincide. The main result is an upper bound of 10 on the price of anarchy for this adversary, for link cost (Formula presented.). New proof techniques are required to obtain this bound, compared to the version with unilateral link formation. For the second adversary, we also prove a bound tight up to constants, namely (Formula presented.), where n is the number of players. © 2016 Springer Science+Business Media New York Source


Miloch W.J.,University of Oslo | Block D.,University of Kiel
Physics of Plasmas | Year: 2012

The charging of dust grain in the wake of another grains in sonic and supersonic collisionless plasma flows is studied by numerical simulations. We consider two grains aligned with the flow, as well as dust chains and multiple grain arrangements. It is found that the dust charge depends significantly on the flow speed, distance between the grains, and the grain arrangement. For two and three grains aligned, the charges on downstream grains depend linearly on the flow velocity and intergrain distance. The simulations are carried out with DiP3D, a three dimensional particle-in-cell code with both electrons and ions represented as numerical particles [W. J. Miloch et al., Phys. Plasmas 17, 103703 (2010)]. © 2012 American Institute of Physics. Source


Tautz D.,Max Planck Institute For Evolutionsbiologie | Domazet-Loso T.,University of Kiel | Domazet-Loso T.,Ruder Boskovic Institute
Nature Reviews Genetics | Year: 2011

Gene evolution has long been thought to be primarily driven by duplication and rearrangement mechanisms. However, every evolutionary lineage harbours orphan genes that lack homologues in other lineages and whose evolutionary origin is only poorly understood. Orphan genes might arise from duplication and rearrangement processes followed by fast divergence; however, de novo evolution out of non-coding genomic regions is emerging as an important additional mechanism. This process appears to provide raw material continuously for the evolution of new gene functions, which can become relevant for lineage-specific adaptations. © 2011 Macmillan Publishers Limited. All rights reserved. Source


Ghaddar F.,American University of Beirut | Cascorbi I.,University of Kiel
Pharmacogenomics | Year: 2011

Despite the fast-growing literature and the emerging support from regulatory drug agencies, the translation of pharmacogenetics (PGx) into the clinic is still rather limited; it seems that many existing challenges are yet to be overcome prior to an extensive adoption of PGx-based diagnostics. This article describes the results of an explorative nonrepresentative survey that attempted to evaluate the perceived status quo of, and the obstacles facing, PGx implementation in clinical practice in countries with emerging and developing economies versus countries with advanced economies. This study is a useful starting point to help gain better insight into the international, rather than merely the regional, barriers facing the lag in PGx implementation in the clinic. A more transparent picture about these priorities can be constructed through conducting a similar study on a more representative sample of respondents/participants. © 2011 Future Medicine Ltd. Source


This study applied social-cognitive models of aggression in order to examine relations between video game use and aggressive tendencies and biases in social information processing. To this end, 499 secondary school students (aged 12-16) completed a survey on two occasions one year apart. Hierarchical regression analysis probed media effects and selection effects and included relevant contextual variables (parental monitoring of media consumption, impulsivity, and victimization). Results revealed that it was not the consumption of violent video games but rather an uncontrolled pattern of video game use that was associated with increasing aggressive tendencies. This increase was partly mediated by a hostile attribution bias in social information processing. The influence of aggressive tendencies on later video game consumption was also examined (selection path). Adolescents with aggressive traits intensified their video game behavior only in terms of their uncontrolled video game use. This was found even after controlling for sensation seeking and parental media control. © Vandenhoeck & Ruprecht GmbH & Co. KG, Göttingen 2011. Source


Strohle A.,University of Kiel
Molecular nutrition & food research | Year: 2010

Over the past decade, a trend toward molecularization, which could be observed in almost all bioscientific disciplines, now appears to have also developed in nutritional science. However, molecular nutrition research gives birth to a series of questions. Therefore, we take a look at the epistemological foundation of (molecular) nutritional science. We (i) analyze the scientific status of (molecular) nutritional science and its position in the canon of other scientific disciplines, (ii) focus on the cognitive aims of nutritional science in general and (iii) on the chances and limits of molecular nutrition research in particular. By taking up the thoughts of an earlier work, we are analyzing (molecular) nutritional science from a strictly realist and emergentist-naturalist perspective. Methodologically, molecular nutrition research is bound to a microreductive research approach. We emphasize, however, that it need not be a radical microreductionism whose scientific reputation is not the best. Instead we favor moderate microreductionism, which combines reduction with integration. As mechanismic explanations are one of the primary aims of factual sciences, we consider it as the task of molecular nutrition research to find profound, i.e. molecular-mechanismic, explanations for the conditions, characteristics and changes of organisms related to the organism-nutrition environment interaction. Source


Meyer-Lueckel H.,University of Kiel | Tschoppe P.,Charite - Medical University of Berlin
Journal of Dentistry | Year: 2010

Objective: Besides the use of saliva substitutes, patients suffering from hyposalivation are instructed to apply fluoride products to prevent caries. Some saliva substitutes have been shown to demineralise enamel; an effect that might be counteracted by the application of fluoride gels or mouthrinses. Combined use of these products with remineralising or neutral saliva substitutes might result in more pronounced remineralisation. Methods: Demineralised bovine enamel specimens were either stored in mineral water [W, control; saturation with respect to octacalcium phosphate (SOCP): 0.7], an experimental demineralising carboxymethylcellulose (CMC)-based solution (C, SOCP: 0.3), or in a modified (SOCP) saliva substitute [Saliva natura (SN), SOCP: 1.6] for five weeks (37 °C). After two weeks half of the exposed surfaces were nail varnished. The following treatments were applied twice daily for 10 min each time (n = 14-18/group): 1: no treatment, 2: Meridol mouthrinse, 3: Elmex sensitive mouthrinse, 4: ProSchmelz fluoride gel, and 5: Elmex gelée. Mineral parameters before and after storage were evaluated from microradiographs. Results: Specimens stored in C showed significantly higher mineral loss compared to W and SN (p < 0.05; ANOVA). For C additional use of fluorides resulted in less demineralisation (p < 0.05) compared to C alone. SN in combination with ProSchmelz led to significantly higher remineralisation compared to all other groups (p < 0.05). Conclusions: Use of fluorides reduces the detrimental effects of the demineralising solution. Treatment with ProSchmelz in combination with storage in a saliva substitute supersaturated with respect to OCP yielded to most pronounced remineralisation under the conditions chosen. © 2010 Elsevier Ltd. All rights reserved. Source


Hartmann M.,University of Kiel | Nielsen H.,Zentrallaboratorium For Geochemie Der Isotope
Isotopes in Environmental and Health Studies | Year: 2012

The isotope ratios of various sulphur components (total sulphur content in the sediment, sulphate and H2S in the pore-water) were measured in a number of cores from recent marine sediments taken from the Kieler Bucht (Kiel Bay) region in the western Baltic Sea. Additionally, the quantitative contents of total sulphur, sulphate, sulphide, chloride, organic carbon, iron and water in the sediment and in the pore-water solutions, respectively, were determined.These investigations provided the following results: 1. The sulphur contained in the sediment (~ 0.3-2% of the dry sample) was for the most part introduced only after sedimentation. This confirms the deliberations of Kaplan et al. [The Distribution and Isotopic Abundance of Sulfur in Recent Marine Sediments off Southern California, Geochim. Cosmochim. Acta27, 297 (1963)]. The organic substance contributes to the sulphur content of the sediment only to an insignificant degree (in our samples with ~5-10% of the total sulphur).2. The sulphate in the pore-waters has been identified as a source for sulphur in the sediment. During normal sedimentation, the exchange of sulphate by diffusion significant for changes in the sulphur content goes down to a sediment depth of 4-6 cm. In this process, the sulphate consumed by reduction and formation of sulphide or pyrite is mostly replaced. The uppermost sediment layer thus represents a partially open system for the total sulphur. The diagenesis of the sulphur is allochemical. At depths below 4-6 cm, we are dealing with a closed system. The further diagenesis of sulphur here is isochemical.3. The isotope values of the sediment sulphur are influenced primarily by sulphur which comes into the sediment by diffusion and which is bound by subsequent bacteriological reduction as either sulphide or pyrite. As a consequence of the prevailing reduction of 32S and reverse-diffusion of sulphate into the open sea water, a 32S enrichment takes place in the uppermost layer of the sediment. The δ34S values in the sediment range in general between-15 and-35‰, while seawater sulphate is+20‰. No relationship could be established between sedimentological or chemical changes and isotope ratios. In the cores, successive sandy and clayish layers showed no change in the δ34S values. However, the sedimentation rate seems to influence δ34S values. In one core with relatively low sedimentation rates, the δ34S values varied between-29 and-33‰, while cores with higher sedimentation rates showed values between-17 and-24‰.4. As sediment depth increases, the pore-water sulphate shows, as expected, decreasing concentrations (in a depth of 30-40 cm, we found between 20 and 70% of the seawater values), and increasing δ34S values (in one case reaching more than+60‰).The concentration of sulphide in the pore-water increases, however, with sediment depth (to various extents, reaching 80 mg S per litre in one case). The δ34S values of the pore-water sulphide in all cores show increases paralleling the sulphate sulphur, with a nearly constant δ difference of 50-60‰ in all cores.This seems to confirm the genetic relationship between the two components. © 2012 Copyright Taylor and Francis Group, LLC. Source


Meier H.,University of Hamburg | Rehdanz K.,University of Kiel | Rehdanz K.,Kiel Institute for The World Economy
Energy Economics | Year: 2010

In Great Britain, several policy measures have been implemented in order to increase energy efficiency and reduce carbon emissions. In the domestic sector, this could, for example, be achieved by improving space heating efficiency and thus decreasing heating expenditure. However, in order to efficiently design and implement such policy measures, a better understanding of the determinants affecting heating expenditure is needed. In this paper we examine the following determinants: socio-economic factors, building characteristics, heating technologies and weather conditions. In contrast to most other studies we use panel data to investigate household demand for heating in Great Britain. Our data sample is the result of an annual set of interviews with more than 5000 households, starting in 1991 and ending in 2005. The sample represents a total of 64,000 observations over the fifteen-year period. Our aim is to derive price and income elasticities both for Britain as a whole and for different types of household. Our results suggest that differences exist between owner-occupied and renter households. These households react differently to changes in income and prices. Our results also imply that a number of socio-economic criteria have a significant influence on heating expenditure, independently of the fuel used for heating. Understanding the impacts of different factors on heating expenditure and impact differences between types of household is helpful in designing target-oriented policy measures. © 2009 Elsevier B.V. Source


Luthje P.,Karolinska Institutet | Brauner H.,Karolinska Institutet | Ramos N.L.,Karolinska Institutet | Ovregaard A.,Karolinska Institutet | And 4 more authors.
Science Translational Medicine | Year: 2013

Epidemiological data imply a role of estrogen in the pathogenesis of urinary tract infections (UTIs), although the underlying mechanisms are not well understood. However, it is thought that estrogen supplementation after menopause decreases the risk of recurrent infections. We sought to investigate the influence of estrogen on host-pathogen interactions and the consequences for UTI pathogenesis. We analyzed urothelial cells from menstruating and postmenopausal women before and after a 2-week period of estrogen supplementation, and also studied the influence of estradiol during Escherichia coli UTI in a mouse infection model. Important findings were confirmed in two human urothelial cell lines. We identified two epithelial defense mechanisms modulated by estrogen. Estrogen induced the expression of antimicrobial peptides, thereby enhancing the antimicrobial capacity of the urothelium and restricting bacterial multiplication. In addition, estrogen promoted the expression and redistribution of cell-cell contact-associated proteins, thereby strengthening the epithelial integrity and preventing excessive loss of superficial cells during infection. These two effects together may prevent bacteria from reaching deeper layers of the urinary tract epithelium and developing reservoirs that can serve as a source for recurrent infections. Thus, this study presents some underlying mechanisms for the beneficial effect of estradiol after menopause and supports the application of estrogen in postmenopausal women suffering from recurrent UTI. Copyright 2013 by the American Association for the Advancement of Science; all rights reserved. Source


Abstract Aquaporins (AQPs) are channel proteins which facilitate the bidirectional membrane permeation of small neutral molecules such as water and glycerol. A convenient way to characterize their permeability is by growth of transformed Saccharomyces cerevisiae deletion strains on nutrient-limited substrates. We selected a yeast strain deficient in its endogenous ammonium transporters Mep1-3 and aquaglyceroporin Fps1 in order to study the ammonia permeability of heterologously expressed AQPs. Surprisingly, AQP-expression improved yeast growth at high, not low, concentrations of unprotonated ammonia. At neutral or mildly alkaline pH, ammonia concentrations above 10 μM decreased the growth rate and especially the number of yeast cell duplications, but did not affect the lag phase. AQP-expression raised the threshold to about 100 μM. The exchange of ammonium ions for amino acids or urea did not completely abolish this effect. AQPs capable of rescuing growth had a selectivity filter wide enough to permit passage of molecules larger than water but smaller than glycerol. It appears that the endogenous aquaglyceroporin Fps1 may, under alkaline conditions, be beneficial to yeast by facilitating the membrane permeation of an as yet unidentified molecule other than glycerol. Source


Perino G.,University of East Anglia | Requate T.,University of Kiel
Journal of Environmental Economics and Management | Year: 2012

We show that for a broad class of technologies the relationship between policy stringency and the rate of technology adoption is inverted U-shaped. This happens when the marginal abatement cost (MAC) curves of conventional and new technologies intersect, which invariably occurs when emissions are proportional to output and technological progress reduces emissions per output. This outcome does not result from policy failure. On the contrary, in social optimum, the relationship between the slope of the marginal damage curve and the rate of technology adoption is also inverted U-shaped. Under more general conditions, these curves can look even more complicated (e.g., such as inverted W-shaped). © 2012 Elsevier Inc. Source


This paper presents a cost-benefit analysis of three different use systems for the remaining cloud forests in Ethiopia, which at present are being depleted at the rate of 8% per year. These use systems are a) traditional conversion to crop land, b) sustainable management of the forest (e.g. by growing high-quality, semi-forest coffee), and c) strict conservation. We find that under business as usual conversion to cropland yields the highest net present income value for the local population. Taking into account watershed services, sustainable forest use is in the best interests of the country for discount rates of 10% or lower. Taking into account the global benefits of biodiversity conservation and carbon storage, sustainable forest management also yields the highest total economic value while strict conservation does not pass a cost-benefit test even at a discount rate of 3%. © 2012 Elsevier B.V. Source


Horbach A.,University of Kiel
Operations Research Letters | Year: 2010

We prove a new combinatorial property of the maximum round robin tournament (MRRT) problem. This property allows us to answer negatively the question of Briskorn, whether the optimal objective value of the MRRT problem and that of its conventional linear relaxation always coincide. © 2009 Elsevier B.V. All rights reserved. Source


The ability of multicellular organisms to detect and respond to microorganisms is fundamental and has ancient evolutionary origins. In this review, I evaluate our current understanding of the evolution of epithelial-based innate immunity in Hydra, an apparently simple animal that shares deep evolutionary connections with all animals, including humans. I highlight growing evidence that the innate immune system with its host-specific antimicrobial peptides and rich repertoire of pattern recognition receptors has evolved in response to the need for controlling resident beneficial microbes rather than to defend against invasive pathogens. These findings provide new insight into how developmental pathways beyond those associated with the immune system, such as stem cell transcriptional programs, interact with environmental cues such as microbes. © 2014 Elsevier Ltd. All rights reserved. Source


Al Hagrey S.A.,University of Kiel | Petersen T.,Goethe Schule
Geophysics | Year: 2011

An exact mapping of root zones is essential to understand plant growth, root biomass, and soil functions important for environmental and climatic management and protection. Numerical and experimental techniques of the electrical resistivity tomography were applied in 2D and 3D to resolve small root zones in the centimeter range. Numerically, we studied two scenarios of conductive and resistive root zones as a function of (1) eight different quadripole electrode configurations (standard, nonstandard, and optimized), (2) four different survey designs with electrode arrays at the soil surface and in boreholes, and (3) eight different inversion constraints. The best resolved output tomogram was evaluated semiquantitatively using the criteria of visual similarity to the input model, least data set, rms error, and iteration number and quantitatively by the model difference relative to the input model. The results showed that the surface-borehole configurations have the best resolution for the whole root zone. The single-surface and borehole surveys resolve only the respective upper and middle-lower root parts. The results reflect the potential of the optimization approach to generate small data sets of far higher resolution than the standard sets. Based on these results, we used the surface-borehole survey around a young hibiscus planted in a sandy soil in a laboratory experiment. The surface-borehole surveys using small, optimized configurations result in an optimum spatiotemporal resolution for simultaneous applications for 3D mapping of targets (root zones and water and soil heterogeneities) and 4D monitoring of their processes. © 2011 Society of Exploration Geophysicists. Source


Brasch J.,University of Kiel
JDDG - Journal of the German Society of Dermatology | Year: 2010

Dermatophytes are hyphomycetes that can degrade keratin. This puts them in a position to cause infections of the keratin-containing superficial skin. The resulting clinical picture is called tinea. The pathogenesis and course of tinea is decisively determined by pathogen-related factors and by the defense mechanisms of the host. An infection starts with an adherence of fungal propagules, followed by the formation of hyphae that can spread within the tissue. This process is accompanied by a release of fungal enzymes and other pathogenic factors. Next keratinocytes are activated, the epidermal barrier is destroyed, epidermal proliferation is enhanced and defensins are expressed within the epidermis. In addition, innate and specific immune responses are initiated, involving neutrophilic granulocytes, macrophages, antibodies and T cells. The cellular mechanisms are thought to be crucial for healing. Special conditions apply to nail infections, because within nail plates the fungi are not accessible to effective defense mechanisms, as well as to infections of hair follicles that contain specific concentrations of steroid hormones. Dermatophytes that penetrate into the dermis can cause granulomatous inflammatory reactions and systemic immune reactions are supposed to be a trigger of so-called id reactions. © Blackwell Verlag GmbH, Berlin. Source


OBJECTIVES:: Junctional ectopic tachycardia is a frequent complication after pediatric cardiac surgery. A uniform definition of postoperative junctional ectopic tachycardia has yet to be established in the literature. The objective of this study is to analyze differences in the general and age-related prevalence of postoperative junctional ectopic tachycardia according to different diagnostic definitions. DESIGN:: Data files and electrocardiograms of 743 patients (age, 1 d to 17.6 yr) who underwent surgery for congenital heart disease during a 3-year period were reviewed. The prevalence of postoperative junctional ectopic tachycardia in this cohort was determined according to six different definitions identified in the literature and one definition introduced for analytical purposes. Agreement between the definitions was analyzed according to Cohen κ coefficients. A receiver operating characteristic analysis was performed to determine the ability of different definitions to discriminate between patients with increased postoperative morbidity and without. SETTING:: A university-affiliated tertiary pediatric cardiac PICU. PATIENTS:: Infants and children who underwent heart surgery. INTERVENTIONS:: None. MEASUREMENTS AND MAIN RESULTS:: The prevalence of postoperative junctional ectopic tachycardia ranged from 2.0% to 8.3% according to the seven different definitions. Even among definitions for which the general prevalence was almost equal, the distribution according to age varied. Most definitions used a frequency criterion to define postoperative junctional ectopic tachycardia. Definitions based on a fixed frequency criterion did not identify cases of postoperative junctional ectopic tachycardia in patients older than 12 months. The grade of agreement was moderate or poor between definitions using a fixed or dynamic frequency criterion and those not based on a critical heart rate (κ = 0.37–0.66). In the receiver operating characteristic analysis, the definition with a fixed frequency criterion of 180 beats/min or an age-related frequency criterion according to the 95th percentile showed the optimal cut-off value to determine increased postoperative morbidity. CONCLUSIONS:: Different definitions of junctional ectopic tachycardia after pediatric cardiac surgery lead to relevant differences in the reported prevalence and age distribution pattern. A uniform definition of postoperative junctional ectopic tachycardia is needed to provide comparable study results and to improve the diagnosis of junctional ectopic tachycardia in pediatric patients. ©2016The Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies Source


Luning U.,University of Kiel
Angewandte Chemie - International Edition | Year: 2012

On/off catalysts: Control over catalysis can be gained when the catalysts can be switched between an active and a nonactive state by external stimuli. In recent examples, orthogonal signals-light, pH, or the addition of ions-are used for the switching. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Ludewig A.H.,University of Kiel
WormBook : the online review of C. elegans biology | Year: 2013

Over the past 10 years, the relevance of small-molecule signaling for many aspects of C. elegans development and behavior has become apparent. One prominent group of small-molecule signals are the ascarosides, which control dauer entry and exit as well as a variety of sex-specific and social behaviors, including male attraction, hermaphrodite repulsion, olfactory plasticity, and aggregation. This wide range of biological functions is facilitated by a great diversity of ascaroside chemical structures. These are based on the sugar ascarylose, which is linked to fatty acid-like side chains of varying lengths and often decorated further with building blocks derived from amino acids, folate, and other primary metabolites. Different ascarosides or combinations of ascarosides mediate different phenotypes, and even small differences in chemical structures are often associated with strongly altered activity profiles. Additional complexity arises from concentration-dependent effects and synergism between different ascarosides. The ascarosides are sensed by several types of chemosensory head neurons, including the ASK, ASI, and ADL neurons as well as the male-specific CEM neurons. Ascaroside perception is mediated by diverse families of G-protein coupled membrane receptors that act upstream of conserved signal transduction pathways, including insulin/IGF-1 signaling and transforming growth factor beta (TGF-β) signaling. Biosynthesis of the ascarosides appears to integrate input from several primary metabolic pathways, including peroxisomal β-oxidation of long-chain fatty acids and amino acid catabolism. Life stage, sex, as well as food availability and other environmental factors affect ascaroside biosynthesis, suggesting that ascaroside signaling communicates detailed information about life history and metabolic state. Source


Hassink R.,University of Kiel | Klaerding C.,Agiplan GmbH
Regional Studies | Year: 2012

Hassink R. and Klaerding C. The end of the learning region as we knew it; towards learning in space, Regional Studies. Since its launch in the mid-1990s, the learning region has been much debated by academics and applied in regional policies, which are as such positive signs. However, the concept has also been criticized for its fuzziness and its spatial (or regional) fetishism. By applying a cultural and relational perspective, the paper postulates a shift from the learning region concept that studies regions as places of learning to a new analytical framework, learning in space, which studies culture-influenced learning processes in relations or networks of people and organizations. © 2012 Copyright Regional Studies Association. Source


Latif M.,University of Kiel | Martin T.,University of Washington | Park W.,Leibniz Institute of Marine Science
Journal of Climate | Year: 2013

Evidence is presented for the notion that some contribution to the recent decadal trends observed in the Southern Hemisphere, including the lack of a strong Southern Ocean surface warming, may have originated from longer-term internal centennial variability originating in the Southern Ocean. The existence of such centennial variability is supported by the instrumental sea surface temperatures (SSTs), a multimillennial reconstruction of Tasmanian summer temperatures from tree rings, and a millennial control integration of the Kiel Climate Model (KCM). The model variability was previously shown to be linked to changes in Weddell Sea deep convection. During phases of deep convection the surface Southern Ocean warms, the abyssal Southern Ocean cools, Antarctic sea ice extent retreats, and the low-level atmospheric circulation over the Southern Ocean weakens. After the halt of deep convection the surface Southern Ocean cools, the abyssal Southern Ocean warms, Antarctic sea ice expands, and the low-level atmospheric circulation over the Southern Ocean intensifies, consistent with what has been observed during the recent decades. A strong sensitivity of the time scale to model formulation is noted. In the KCM, the centennial variability is associated with global-average surface air temperature (SAT) changes of the order of a few tenths of a degree per century. The model results thus suggest that internal centennial variability originating in the Southern Ocean should be considered in addition to other internal variability and external forcing when discussing the climate of the twentieth century and projecting that of the twenty-first century. © 2013 American Meteorological Society. Source


Thalheim B.,University of Kiel
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2011

The theory of integrity constraints has led to a large body of knowledge and to many applications such as optimisation of schema behaviour through normalisation to schemata which are easier to maintain, as automatic enforcement of database integrity by triggering or other procedural techniques, as quality improvement of data in databases, and as query recompilations due to the knowledge of validity of constraints in a database. Integrity constraints are often misunderstood, are given in the wrong database context or within the wrong database models, often combine a number of very different facets of semantics in databases and are difficult to specify. At the same time, pearls and hidden treasure of the theory of integrity constraints have been already forgotten. We develop a unifying approach to specification and treatment of integrity constraints. We survey some pearls, nuggets and lessons learned with semantic models. © 2011 Springer-Verlag Berlin Heidelberg. Source


Mazanek S.,University of Federal Defense Munich | Hanus M.,University of Kiel
Journal of Visual Languages and Computing | Year: 2011

In this article we show how functional logic programming techniques can be used to construct a bidirectional transformation between structured process models of the business process modeling notation (BPMN) and executable models of the business process execution language (BPEL). We specify the abstract syntax of structured process models by a context-free hypergraph grammar. This grammar can be subsequently transformed into a graph parser using our previously developed G. rappa framework of functional logic GRAPh PArser combinators. The G. rappa framework has been implemented using the functional logic programming language Curry. Furthermore, we show how the constructed parsers can be enriched with semantic computations as required for the synthesis of BPEL from BPMN. Since our parser is a function implemented in a functional logic language, it can be applied in both directions. Thus, given a BPEL model, a corresponding BPMN graph can be constructed with the very same parser. Finally, logic-based parsers can be used for model completion and language generation in a straightforward way. In order to be self-contained, this article also surveys context-free hypergraph grammars, the concepts of the programming language Curry, the example languages BPMN and BPEL, and the ideas of the G. rappa framework. Actually, this article is a literate Curry program and, as such, directly executable. Thus, it contains the complete concise source code of our application. © 2010 Elsevier Ltd. Source


Kopfnagel V.,Hannover Medical School | Harder J.,University of Kiel | Werfel T.,Hannover Medical School
Current Opinion in Allergy and Clinical Immunology | Year: 2013

PURPOSE OF REVIEW: To summarize the findings on the expression of antimicrobial peptides in the skin in inflammatory skin diseases and particularly in atopic dermatitis. Moreover, the literature addressing the functions of antimicrobial peptides (AMPs) beyond antimicrobial activities with impact on allergic skin inflammation is summarized as well. RECENT FINDINGS: Although lower expressed than in psoriasis, most AMPs have been shown to be either constitutively expressed or upregulated in atopic dermatitis as well. A number of immunoregulatory functions which might impact on allergic skin inflammation have been described for several antimicrobial peptides, mainly for human β-defensins and the cathelicidin LL-37. SUMMARY: From the recent literature, there is considerable evidence that AMPs are induced in the skin in atopic dermatitis. However, some studies suggest that the induction, release or mobilization of some AMPs in atopic dermatitis may not reach sufficient levels to provide adequate control of cutaneous microbial colonization. Th2 cytokines appear to negatively influence the expression and induction of some AMPs. A number of immunoregulatory functions have been described for several AMPs. Most of them point to a proinflammatory function of AMPs in addition to their antimicrobial activities. Further studies are needed to clarify the role of AMPs in atopic dermatitis. © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins. Source


Irmler U.,University of Kiel
Acta Entomologica Musei Nationalis Pragae | Year: 2015

Recent collections of Osoriinae from Cuba revealed three new species, Allotrochus cubensis sp. nov., Thoracophorus cubensis sp. nov., and Antillosorius martini sp. nov. In total, 34 species of Osoriinae are currently known from this island including the three new ones. An identification key to the species and a list of species with all records known to me are provided. According to this study 8 species (21 %) out of the 39 species are endemic for Cuba and 4 (11 %) show a pantropical distribution. © 2015 National Museum/Narodni muzeum. All rights reserved. Source


Beghe B.,University of Modena and Reggio Emilia | Rabe K.F.,University of Kiel | Fabbri L.M.,University of Modena and Reggio Emilia
American Journal of Respiratory and Critical Care Medicine | Year: 2013

Phosphodiesterases (PDEs) are a superfamily of enzymes that catalyze the breakdown of cAMP and/or cyclic guanosine monophosphate (GMP) to their inactive form. PDE4 is the main selective cAMP-metabolizing enzyme in inflammatory and immune cells. Because PDE4 is highly expressed in leukocytes and other inflammatory cells involved in the pathogenesis of inflammatory lung diseases, such as asthma and chronic obstructive pulmonary disease (COPD), inhibition of PDE4 has been predicted to have an antiinflammatory effect and thus therapeutic efficacy. The limited and inconsistent efficacy and side effects of the early compounds made their further development less desirable in asthma, given the excellent efficacy/tolerability ratio of inhaled steroids. The lack of effective antiinflammatory drug treatment for COPD has thus shifted the interest in development toward COPD. Roflumilast, the only PDE4 inhibitor that has reached the market because of the good efficacy/tolerability ratio, is recommended for patients with COPD with severe airflow limitation, symptoms of chronic bronchitis, and a history of exacerbations, whose disease is not adequately controlled by long-acting bronchodilators. Albeit safe, it maintains significant side effects (diarrhea, nausea, weight loss) that make it intolerable in some patients. Future developments of PDE4 inhibitors include extended indications of roflumilast (1) in patients with COPD,and(2) inother respiratory (e.g., asthma)andnonrespiratory chronic inflammatory/metabolic conditions (e.g., diabetes), as well as (3) the development of new molecules with PDE4 inhibitory properties with an improved efficacy/tolerability profile. © 2013 by the American Thoracic Society. Source


Buckleton J.S.,ESR Ltd. | Krawczak M.,University of Kiel | Weir B.S.,University of Washington
Forensic Science International: Genetics | Year: 2011

Mitochondrial DNA (mtDNA) and the non-recombining portion of the Y-chromosome are inherited matrilinealy and patrilinealy, respectively, and without recombination. Collectively they are termed 'lineage markers'. Lineage markers may be used in forensic testing of an item, such as a hair from a crime scene, against a hypothesised source, or in relationship testing. An estimate of the evidential weight of a match is usually provided by a count of the occurrence in some database of the mtDNA or Y-STR haplotype under consideration. When the factual statement of a count in the database is applied to a case, issues of relevance of the database and sampling uncertainty may arise. In this paper, we re-examine the issues of sampling uncertainty, the relevance of the database, and the combination of autosomal and lineage marker evidence. We also review the recent developments by C.H. Brenner. © 2010 Elsevier Ireland Ltd. All rights reserved. Source


Thalheim B.,University of Kiel
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2012

Models, modelling languages, modelling frameworks and their background have dominated conceptual modelling research and information systems engineering for last four decades. Conceptual models are mediators between the application world and the implementation or system world. Currently conceptual modelling is rather a craft and at the best an art. We target on a science and culture of conceptual modelling. Models are governed by their purpose. They are used by a community of practice and have a function within application cases. Language-based models use a language as a carrier. Therefore, semiotics of models must be systematically developed. This paper thus concentrates on the linguistic foundation of conceptual modelling. © 2012 Springer-Verlag. Source


PROBLEMS/OBJECTIVES: Epstein-Barr virus (EBV) is commonly associated with nasopharyngeal carcinoma and Burkitt's lymphoma, but association with hypopharyngeal and laryngeal tumours is rare. To the best of our knowledge, this is the first case report of an EBV-associated diffuse large B-cell lymphoma (DLBCL) of the hypopharynx. A 63-year-old male patient suffering from chronic lymphocytic leukemia presented with swallowing disorders and a sore throat. Panendoscopy with laser surgical resection of tissue specimens was performed. Immunohistochemical and molecular genetic diagnostics, including EBV-encoded small RNA in situ hybridization, confirmed the diagnosis of an EBV-associated DLBCL of the hypopharynx. Ten weeks after the diagnosis, the patient died of disease related to multiple complications. We hypothesize that the EBV infection was triggered by long-term immunosuppressive therapy that led secondarily to the development of a DLBCL. Otorhinolaryngologists should keep in mind that lymphomas might develop in the entire pharynx. Source


Diel R.,University of Kiel | Lampenius N.,University of Hohenheim | Nienhaus A.,University of Hamburg
PharmacoEconomics | Year: 2015

Objective: In view of the goal of eliminating tuberculosis (TB) by 2050, economic evaluations of interventions against the development of TB are increasingly requested. Little research has been published on the incremental cost effectiveness of preventative therapy (PT) in groups at high risk for progression from latent TB infection (LTBI) with Mycobacterium TB (MTB) to active disease. A systematic review of studies with a primary focus on model-driving inputs and methodological differences was conducted. Methods: A search of MEDLINE, the Cochrane Library and EMBASE to July 2014 was undertaken, and reference lists of eligible articles and relevant reviews were examined. Results: A total of 876 citations were retrieved, with a total of 24 studies being eligible for inclusion, addressing six high-risk groups other than contact persons. Results varied considerably between studies and countries, and also over time. Although the selected studies generally demonstrated cost effectiveness for PT in HIV-infected subjects and healthcare workers (HCWs), the outcome of these analyses can be questioned in light of recent epidemiologic data. For immigrants from high TB-burden countries, patients with end-stage renal disease, and the immunosuppressed, now defined as further vulnerable groups, no consistent recommendation can be taken from the literature with respect to cost effectiveness of screening and treating LTBI. When the concept of a fixed willingness-to-pay (WTP) threshold as a prerequisite for final categorization was used, the sums ranged between ‘no specification’ and US$100,000 per quality-adjusted life-year. Conclusions: To date, incremental cost-effectiveness analyses on PT in groups at high risk for TB progression, other than contacts, are surprisingly scarce. The variation found between studies likely reflects variations in the major epidemiologic factors, particularly in the estimates on the accuracy of the tuberculin skin test (TST) and interferon-gamma release assays (IGRA) as screening methods used before considering PT. Further research, including explicit evaluation of local epidemiological conditions, test accuracy, and methodology of WTP thresholds, is needed. © 2015, Springer International Publishing Switzerland. Source


Danilenko N.,University of Kiel
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2012

We show how to develop a purely functional algorithm that computes maximum matchings in bipartite graphs by using relation algebra. Our algorithm is based upon the representation of graphs by lists of successor lists and a generalisation to specific container types is discussed. The algorithm itself can be implemented in Haskell and we will provide a complete implementation using the successor list model. © 2012 Springer-Verlag. Source


Thalheim B.,University of Kiel
Journal of Universal Computer Science | Year: 2010

Conceptual modelling is a widely applied practice and has led to a large body of knowledge on constructs that might be used for modelling and on methds that might be useful for modelling. It is commonly accepted that database application development is based on conceptual modelling. It is however surprising that only very few publications have been published on a theory of conceptual modelling. Modelling is typically supported by languages that are well-founded and easy to apply for the description of the application domain, the requirements and the system solution. It is thus based on a theory of modelling constructs. At the same time, modeling incorporates a description of the application domain and a prescription of requirements for supporting systems. It is thus based on methods of application domain gathering. Modelling is also an engineering activity with engineering steps and engineering results. It is thus engineering. The first facet of modelling has led to a huge body of knowledge. The second facet is considered from time to time in the scientific literature. The third facet is underexposed in the scientific literature. This paper aims in developing principles of conceptual modelling. They cover modeling constructs as well as modelling activities as well as modelling properties. We first clarify the notion of conceptual modelling. Principles of modelling may be applied and accepted or not by the modeler. Based on these principles we can derive a theory of conceptual modelling that combines foundations of modelling constructs, application capture and engineering. A general theory of conceptual modelling is far too comprehensive and far too complex. It is not yet visible how such a theory can be developed. This paper therefore aims in introducing a framework and an approach to a general theory of conceptual modelling. We are however in urgent need of such a theory. We are sure that this theory can be developed and use this paper for the introduction of the main ingredients of this theory. Source


The prognostic impact of minimal residual disease (MRD) has been demonstrated for several hematologic malignancies. While in acute lymphoblastic leukemias MRD assessment by polymerase chain reaction (PCR)-based methods has been established as an important tool for clinical risk assessment and is part of clinical management, data demonstrating a prognostic value of MRD in mantle cell lymphoma (MCL) were sparse and results from randomized trials have been published only recently. In the present review technical aspects of different MRD detection methods are discussed, as well as the prognostic relevance of MRD in the context of clinical trials in patients with MCL. Furthermore, recommendations are given for workflow and useful implication of MRD in future clinical trials design. © 2011. Source


Schultz C.,University of Kiel | Salomo S.,Technical University of Denmark | Talke K.,TU Berlin
Journal of Product Innovation Management | Year: 2013

Portfolio innovativeness is a central variable in innovation management. However, the impact of portfolio innovativeness on new product development (NPD) performance is unclear, which may partly be due to the construct's multifaceted nature. Different facets may reflect different degrees of innovativeness and may have different relationships with performance. In addition, firm members with different functional backgrounds may perceive and thus assess these facets differently, which again may influence the performance effect of portfolio innovativeness. Based on a sample of 746 CEOs and marketing as well as technology professionals from 117 firms and using Item Response Theory (IRT), a multifaceted scale of portfolio innovativeness, whose facets are able to cover the entire innovativeness spectrum, is developed. In addition, it is shown that the performance impact of portfolio innovativeness is dependent on the facets included in the scale, and on the specialization of the professional assessing the facets. Inverted U-shaped performance effects are found when the scale covers the entire spectrum of innovativeness, and linear positive or zero effects with different types of more narrowly modeled scales. Inverted U-shaped performance effects are also found when technology professionals assess the facets, while the assessments by marketing professionals lead to linear positive effects. © 2013 Product Development & Management Association. Source


Claes A.-K.,University of Toronto | Claes A.-K.,Leibniz Center for Medicine and Biosciences | Claes A.-K.,University of Kiel | Zhou J.Y.,University of Toronto | Philpott D.J.,University of Toronto
Physiology | Year: 2015

The NOD-like receptors (NLRs) are cytosolic pattern-recognition receptors, which are critically involved in mucosal immune defense. The association of the NLR, NOD2, with inflammatory bowel disease first pointed to the NLRs potential function as guardians of the intestinal barrier. Since then, several studies have emphasized the importance of NLRs in maintaining gut homeostasis and intestinal infections, and in shaping the microbiota. In this review, we will highlight the function of NLRs in intestinal inflammation. © 2015 Int. Source


Behne M.J.,University of Hamburg | Jensen J.-M.,University of Kiel
Advances in Experimental Medicine and Biology | Year: 2012

Calcium is the ubiquitous second messenger system in cell biology (e.g., [1, 2]), as shown in great detail in this volume. In contrast, calcium has been implicated in a host of functions in skin, which have seen only partial clarification to date. Within this chapter, we will present an overview of known physiologic and pathophysiologic aspects to give a perspective of the overall role of calcium, focusing on epidermis. © 2012 Springer Science+Business Media B.V. Source


Mehdorn H.M.,University of Kiel
Advances and technical standards in neurosurgery | Year: 2016

Intracranial meningiomas are tumors arising from the covering cells of the arachnoid layer of the dura mater or from the intraventricular choroid plexus. While mostly benign tumors, they still represent a major challenge to neurosurgeons and other medical disciplines involved in their diagnostic and therapeutic management. Although this review intends to give some state-of-the-art information from the literature, it is mainly based on personal experiences since more than 30 years caring for more than 1500 meningioma patients and point to a few new strategies to further improve on patient outcome.Diagnostics are based on magnetic resonance imaging which shows the relationship between tumor and surrounding intracranial structures, particularly the brain but also the vasculature and to some extent the cranial nerves. Furthermore, it may suggest the grading of the tumor and is very helpful in the postoperative diagnosis of complications and later follow-up course.Surgery still is the main treatment with the aim to completely remove the tumor; also in cases of recurrence, other additional options include radiotherapy and radiosurgery for incompletely removed or recurrent meningiomas. Postoperative chemotherapy has not been shown to provide substantial benefit to the patient especially in highly malignant meningiomas.All therapy options should be intended to provide the patient with the best possible functional outcome. Patients' perspective is not always equivalent to surgeons' perspectives. Neuropsychological evaluation and additional guidance of patients harboring meningiomas have proven to be important in modern neurosurgical intracranial tumor treatment. Their help beyond neurosurgical care facilitates the patients to lead an independent postoperative life. Source


Mild therapeutic hypothermia (MTH) has been shown to result in better neurological outcome after cardiopulmonary resuscitation. Percutaneous coronary intervention (PCI) may also be beneficial in patients after out-of-hospital cardiac arrest (OHCA). A selected cohort study of 2,973 prospectively documented adult OHCA patients within the German Resuscitation Registry between 2004 and 2010. Data were analyzed by backwards stepwise binary logistic regression to identify the impact of MTH and PCI on both 24-hour survival and neurological outcome that was based on cerebral performance category (CPC) at hospital discharge. Odds ratios (95% confidence intervals) were calculated adjusted for the following confounding factors: age, location of cardiac arrest, presumed etiology, bystander cardiopulmonary resuscitation, witnessing, first electrocardiogram rhythm, and thrombolysis. The Preclinical care dataset included 2,973 OHCA patients with 44% initial return of spontaneous circulation (n = 1,302) and 35% hospital admissions (n = 1,040). Seven hundred and eleven out of these 1,040 OHCA patients (68%) were also registered within the Postresuscitation care dataset. Checking for completeness of datasets required the exclusion of 127 Postresuscitation care cases, leaving 584 patients with complete data for final analysis. In patients without PCI (n = 430), MTH was associated with increased 24-hour survival (8.24 (4.24 to 16.0), P < 0.001) and the proportion of patients with CPC 1 or CPC 2 at hospital discharge (2.13 (1.17 to 3.90), P < 0.05) as an independent factor. In normothermic patients (n = 405), PCI was independently associated with increased 24-hour survival (4.46 (2.26 to 8.81), P < 0.001) and CPC 1 or CPC 2 (10.81 (5.86 to 19.93), P < 0.001). Additional analysis of all patients (n = 584) revealed that 24-hour survival was increased by MTH (7.50 (4.12 to 13.65), P < 0.001) and PCI (3.88 (2.11 to 7.13), P < 0.001), while the proportion of patients with CPC 1 or CPC 2 was significantly increased by PCI (5.66 (3.54 to 9.03), P < 0.001) but not by MTH (1.27 (0.79 to 2.03), P = 0.33), although an unadjusted Fisher exact test suggested a significant effect of MTH (unadjusted odds ratio 1.83 (1.23 to 2.74), P < 0.05). PCI may be an independent predictor for good neurological outcome (CPC 1 or CPC 2) at hospital discharge. MTH was associated with better neurological outcome, although subsequent logistic regression analysis did not show statistical significance for MTH as an independent predictor for good neurological outcome. Thus, postresuscitation care on the basis of standardized protocols including coronary intervention and hypothermia may be beneficial after successful resuscitation. One of the main limitations may be a selection bias for patients subjected to PCI and MTH. Source


Deckert M.,University of Cologne | Montesinos-Rongen M.,University of Cologne | Brunn A.,University of Cologne | Siebert R.,University of Kiel
Acta Neuropathologica | Year: 2014

Primary lymphoma of the central nervous system (CNS, PCNSL) is a specific diffuse large B cell lymphoma entity arising in and confined to the CNS. Despite extensive research since many decades, the pathogenetic mechanisms underlying the remarkable tropism of this peculiar malignant hematopoietic tumor remain still to be elucidated. In the present review, we summarize the present knowledge on the genotypic and phenotypic characteristics of the tumor cells of PCNSL, give an overview over deregulated molecular pathways in PCNSL and present recent progress in the field of preclinical modeling of PCNSL in mice. With regard to the phenotype, PCNSL cells resemble late germinal center exit IgM+IgD+ B cells with blocked terminal B cell differentiation. They show continued BCL6 activity in line with ongoing activity of the germinal center program. This together with the pathways deregulated by genetic alterations may foster B cell activation and brisk proliferation, which correlated with the simultaneous MYC and BCL2 overexpression characteristic for PCNSL. On the genetic level, PCNSL are characterized by ongoing aberrant somatic hypermutation that, besides the IG locus, targets the PAX5, TTF, MYC, and PIM1 genes. Moreover, PCNSL cells show impaired IG class switch due to sμ region deletions, and PRDM1 mutations. Several important pathways, i.e., the B cell receptor (BCR), the toll-like receptor, and the nuclear factor-κB pathway, are activated frequently due to genetic changes affecting genes like CD79B, SHIP, CBL, BLNK, CARD11, MALT1, BCL2, and MYD88. These changes likely foster tumor cell survival. Nevertheless, many of these features are also present in subsets of systemic DLBLC and might not be the only reasons for the peculiar tropism of PCNSL. Here, preclinical animal models that closely mimic the clinical course and neuropathology of human PCNSL may provide further insight and we discuss recent advances in this field. Such models enable us to understand the pathogenetic interaction between the malignant B cells, resident cell populations of the CNS, and the associated inflammatory infiltrate. Indeed, the immunophenotype of the CNS as well as tumor cell characteristics and intracerebral interactions may create a micromilieu particularly conducive to PCNSL that may foster aggressiveness of tumor cells and accelerate the fatal course of disease. Suitable animal models may also serve as a well-defined preclinical system and may provide a useful tool for developing new specific therapeutic strategies. © 2013 Springer-Verlag Berlin Heidelberg. Source


Coelho-Filho O.R.,Brigham and Womens Hospital | Rickers C.,University of Kiel | Kwong R.Y.,Brigham and Womens Hospital | Jerosch-Herold M.,Brigham and Womens Hospital
Radiology | Year: 2013

Contrast material-enhanced myocardial perfusion imaging by using cardiac magnetic resonance (MR) imaging has, during the past decade, evolved into an accurate technique for diagnosing coronary artery disease, with excellent prognostic value. Advantages such as high spatial resolution; absence of ionizing radiation; and the ease of routine integration with an assessment of viability, wall motion, and cardiac anatomy are readily recognized. The need for training and technical expertise and the regulatory hurdles, which might prevent vendors from marketing cardiac MR perfusion imaging, may have hampered its progress. The current review considers both the technical developments and the clinical experience with cardiac MR perfusion imaging, which hopefully demonstrates that it has long passed the stage of a research technique. In fact, cardiac MR perfusion imaging is moving beyond traditional indications such as diagnosis of coronary disease to novel applications such as in congenital heart disease, where the imperatives of avoidance of ionizing radiation and achievement of high spatial resolution are of high priority. More wide use of cardiac MR perfusion imaging, and novel applications thereof, are aided by the progress in parallel imaging, high-field-strength cardiac MR imaging, and other technical advances discussed in this review. © RSNA, 2012. Source


Locatelli F.,Istituto di Ricovero e Cura rattere Scientifico Bambino Gesu Childrens Hospital | Locatelli F.,University of Pavia | Schrappe M.,University of Kiel | Bernardo M.E.,Istituto di Ricovero e Cura rattere Scientifico Bambino Gesu Childrens Hospital | Rutella S.,Istituto di Ricovero e Cura rattere Scientifico Bambino Gesu Childrens Hospital
Blood | Year: 2012

The most common cause of treatment failure in childhood acute lymphoblastic leukemia (ALL) remains relapse, occurring in ∼ 15%-20% of patients. Survival of relapsed patients can be predicted by site of relapse, length of first complete remission, and immunophenotype of relapsed ALL. BM and early relapse (< 30 months from diagnosis), as well as T-ALL, are associated with worse prognosis than isolated extramedullary or late relapse (> 30 months from diagnosis). In addition, persistence of minimal residual disease (MRD) at the end of induction or consolidation therapy predicts poor outcome because children with detectable MRD are more likely to relapse than those in molecular remission, even after allogeneic hematopoietic stem cell transplantation. We offer hematopoietic stem cell transplantation to any child with high-risk features because these patients are virtually incurable with chemotherapy alone. By contrast, we treat children with first late BM relapse of B-cell precursor ALL and good clearance of MRD with a chemotherapy approach. We use both systemic and local treatment for extramedullary relapse, mainly represented by radiotherapy and, in case of testicular involvement, by orchiectomy. Innovative approaches, including new agents or strategies of immunotherapy, are under investigation in trials enrolling patients with resistant or more advanced disease. © 2012 by The American Society of Hematology. Source


Ott K.,University of Kiel
Sustainability (Switzerland) | Year: 2014

The article aims to provide some ethical orientation on how sustainability might be actualized by institutions. Since institutionalization is about rules and organization, it presupposes ideas and concepts by which institutions can be substantiated. After outlining terminology, the article deals with underlying ethical and conceptual problems which are highly relevant for any suggestions concerning institutionalization. These problems are: (a) the ethical scope of the sustainability perspective (natural capital, poverty, sentient animals), (b) the theory of justice on which ideas about sustainability are built (capability approach, Rawlsianism), and (c) the favored concept of sustainability (weak, intermediate, and strong sustainability). These problems are analyzed in turn. As a result, a Rawlsian concept of rule-based strong sustainability is proposed. The specific problems of institutionalization are addressed by applying Rawls's concept of branches. The article concludes with arguments in favor of three transnational duties which hold for states that have adopted Rawlsian strong sustainability. Source


Bacteria adapt to growth in lungs of patients with cystic fibrosis (CF) by selection of heterogeneously resistant variants that are not detected by conventional susceptibility testing but are selected for rapidly during antibacterial treatment. Therefore, total bacterial counts and antibiotic susceptibilities are misleading indicators of infection and are not helpful as guides for therapy decisions or efficacy endpoints. High drug concentrations delivered by aerosol may maximize efficacy, as decreased drug susceptibilities of the pathogens are compensated for by high target site concentrations. However, reductions of the bacterial loadinsputum and improvements in lung function were within the same ranges following aerosolized and conventional therapies. Furthermore, the use of conventional pharmacokinetic/pharmacodynamic (PK/PD) surrogates correlating pharmacokinetics in serum with clinical cure and presumed or proven eradication of the pathogen as a basis for PK/PD investigations in CF patients is irrelevant, as minimization of systemic exposure is one of the main objectives of aerosolized therapy; in addition, bacterial pathogens cannot be eradicated, and chronic infection cannot be cured. Consequently, conven-tional PK/PD surrogates are not applicable to CF patients. It is nonetheless obvious that systemic exposure of patients, with all its sequelae, is minimized and that the burden of oral treatment for CF patients suffering from chronic infections is reduced. © 2014, American Society for Microbiology. All Rights Reserved. Source


Ghazal M.,University of Kiel
Quintessence international (Berlin, Germany : 1985) | Year: 2010

To evaluate the wear resistance of artificial denture teeth and their human enamel antagonists in a dual-axis chewing simulator. Four artificial denture teeth--feldspathic ceramic, nanofilled composite resin, experimental acrylic resin with UDMA/PMMA, and interpenetrating polymer networks (IPN) acrylic resin teeth--were tested in this study. Human enamel cusps were used as antagonists. Wear resistance was analyzed by measuring the vertical substance loss and the volume loss of the denture teeth using a laser scanner after 300,000 chewing cycles. In addition, the vertical substance loss of the antagonists was evaluated using an optical macroscope. Data were statistically analyzed using ANOVA. For qualitative analysis of the wear areas, the teeth were sputter coated with gold and evaluated at magnifications of 503 and 1,0003 using SEM. The composite resin teeth exhibited wear that was significantly higher than that of feldspathic ceramic but lower than that of acrylic resin teeth (P<.05). Acrylic resin teeth caused no measurable wear on the enamel antagonists. The wear patterns of the feldspathic ceramic and composite resin teeth can be described as attritional, while a fatigue type of wear was observed in the acrylic resin teeth. The lowest total vertical substance loss was found for the combination composite resin-enamel. Based on the results of this study, composite resin teeth seem to be more suitable for dentures opposing natural teeth than ceramic or acrylic resin teeth in terms of wear resistance. Source


Background: Drug interactions can have desired, reduced or unwanted effects. The probability of interactions increases with the number of drugs taken. The high rate of prescribed drugs in elderly patients (65-year-old patients take an average of 5 drugs) increases the likelihood of drug interactions and thus the risk that drugs themselves can be the cause of hospitalization. According to metaanalyses, up to 7% of hospitalizations are drug-related. Methods: Selective literature review. Results: Drug interactions occur on pharmacodynamic and pharmacokinetic levels. Examples of pharmacodynamic interactions are simultaneous administration of a NSAID and phenprocoumon (additive interaction), or of aspirin and ibuprofen (antagonistic interaction). Pharmacokinetic interactions occur at the levels of absorption (e.g., levothyroxine and neutralizing antacids), elimination (e.g., digoxin and macrolides), and metabolism, as in the competition for cytochrome P450 enzymes (e.g., SSRIs and certain beta-blockers). Conclusion: The systematic knowledge of drug interaction, in particular on the level of absorption, elimination, transport and drug metabolism may help to prevent adverse effects. Predicting pharmacodynamic interactions often demands a deeper understanding of the mechanisms of effect. Electronic prescribing systems are helpful. Source


The estimation of recombination frequencies is a crucial step in genetic mapping. For the construction of linkage maps, nonadditive recombination fractions must be transformed into additive map distances. Two of the most commonly used transformations are Kosambis and Haldanes mapping functions. This paper reports on the calculation of the bias associated with estimation of recombination fractions, Kosambis distances, and Haldanes distances. I calculated absolute and relative biases numerically for a wide range of recombination fractions and sample sizes. I assumed that the ratio of recombinant gametes to the total number of gametes can be adequately represented by a binomial function. I found that the bias in recombination fraction estimates is negative, i.e., the estimator is an underestimate. However, significant values were only obtained when recombination fractions were large and sample sizes were small. The relevant estimates of recombination fractions were, therefore, nearly unbiased. Haldanes and Kosambis distances were found to be strongly biased, with positive bias for the most interesting values of recombination fractions and sample sizes. The bias of Kosambis distance was considerably smaller than the bias of Haldanes distance. Source


Kabelitz D.,University of Kiel
F1000 Medicine Reports | Year: 2010

γδ T lymphocytes are a numerically small subset of T cells with potent cytotoxic activity against a variety of tumor cells. Human γδ T cells expressing the Vγ9Vδ2 T cell antigen receptor recognize endogenous pyrophosphate molecules that are overproduced in transformed cells. Moreover, the intracellular accumulation of such pyrophosphates is strongly enhanced by aminobisphosphonates used in the treatment of osteoporosis and bone metastasis in certain cancer patients. A new concept of cancer immunotherapy is based on the endogenous activation of γδ T cells with aminobisphosphonates plus low-dose interleukin-2. © 2010 Medicine Reports Ltd. Source


Gartner M.,Goethe University Frankfurt | Brodbeck V.,Goethe University Frankfurt | Laufs H.,Goethe University Frankfurt | Laufs H.,University of Kiel | Schneider G.,Goethe University Frankfurt
NeuroImage | Year: 2015

The analysis of spontaneous resting state neuronal activity is assumed to give insight into the brain function. One noninvasive technique to study resting state activity is electroencephalography (EEG) with a subsequent microstate analysis. This technique reduces the recorded EEG signal to a sequence of prototypical topographical maps, which is hypothesized to capture important spatio-temporal properties of the signal.In a statistical EEG microstate analysis of healthy subjects in wakefulness and three stages of sleep, we observed a simple structure in the microstate transition matrix. It can be described with a first order Markov chain in which the transition probability from the current state (i.e., map) to a different map does not depend on the current map. The resulting transition matrix shows a high agreement with the observed transition matrix, requiring only about 2% of mass transport (1/2 L1-distance). In the second part, we introduce an extended framework in which the simple Markov chain is used to make inferences on a potential underlying time continuous process. This process cannot be directly observed and is therefore usually estimated from discrete sampling points of the EEG signal given by the local maxima of the global field power. Therefore, we propose a simple stochastic model called sampled marked intervals (SMI) model that relates the observed sequence of microstates to an assumed underlying process of background intervals and thus, complements approaches that focus on the analysis of observable microstate sequences. © 2014 Elsevier Inc. Source


Holterhus P.-M.,University of Kiel
Pediatric Endocrinology Reviews | Year: 2011

Sex specific development in the human comprises irreversible sexual differentiation of the external genitalia during embryogenesis, sexual maturation of secondary sex characteristics during puberty (e.g., sex specific body proportions, pubertal voice change) and eventually sex specific development of extragenital tissues and organs, including the brain. The presence or absence of androgens acting via the androgen receptor plays a key role therein. At the single cell level, androgens cause reversible short term changes of gene transcription by activating the androgen receptor. From a developmental perspective, this often leads to irreversible long-term changes of anatomy (e.g., sex-specific differentiation of the external genitalia) and function (e.g., sex-specific play behavior in children). These observations are discussed in the context of recent genome-wide gene expression studies and first published experimental data at the epigenome level. In essence, there is evidence for a molecular androgen memory at both the transcriptome and the epigenome level. Source


Lux T.,Kiel Institute for The World Economy | Morales-Arias L.,University of Kiel
Computational Statistics and Data Analysis | Year: 2010

The Markov-switching Multifractal model of asset returns with Student-t innovations (MSM-t henceforth) is introduced as an extension to the Markov-switching Multifractal model of asset returns (MSM). The MSM-t can be estimated via Maximum Likelihood (ML) and Generalized Method of Moments (GMM) and volatility forecasting can be performed via Bayesian updating (ML) or best linear forecasts (GMM). Monte Carlo simulations show that using GMM plus linear forecasts leads to minor losses in efficiency compared to optimal Bayesian forecasts based on ML estimates. The forecasting capability of the MSM-t model is evaluated empirically in a comprehensive panel forecasting analysis with three different cross-sections of assets at the country level (all-share equity indices, bond indices and real estate security indices). Empirical forecasts of the MSM-t model are compared to those obtained from its Gaussian counterparts and other volatility models of the Generalized Autoregressive Conditional Heteroskedasticity (GARCH) family. In terms of mean absolute errors (mean squared errors), the MSM-t (Gaussian MSM) dominates all other models at most forecasting horizons for the various asset classes considered. Furthermore, forecast combinations obtained from the MSM and (Fractionally Integrated) GARCH models provide an improvement upon forecasts from single models. © 2010 Elsevier B.V. All rights reserved. Source


Wietzke L.,Raytrix GmbH | Sommer G.,University of Kiel
Journal of Mathematical Imaging and Vision | Year: 2010

This work covers a fundamental problem of local phase based image analysis: the isotropic generalization of the classical 1D analytic signal to two dimensions. The analytic signal enables the analysis of local phase and amplitude information of 1D signals. Local phase, amplitude and additional orientation information can be extracted by the 2D monogenic signal with the restriction to intrinsically 1D signals. In case of 2D image signals the monogenic signal enables the rotationally invariant analysis of lines and edges. In this work we present the 2D analytic signal as a novel generalization of both the analytic signal and the 2D monogenic signal. In case of 2D image signals the 2D analytic signal enables the isotropic analysis of lines, edges, corners and junctions in one unified framework. Furthermore, we show that 2D signals are defined on a 3D projective subspace of the homogeneous conformal space which delivers a descriptive geometric interpretation of signals providing new insights on the relation of geometry and 2D image signals. Finally, we will introduce a novel algebraic signal representation, which can be regarded as an alternative and fully isomorphic representation to classical matrices and tensors. We will show the solution of isotropic intrinsically 2D image analysis without the need of steering techniques. © Springer Science+Business Media, LLC 2010. Source


Schaefer D.,University of Kiel
Environmental Earth Sciences | Year: 2012

Organic contaminants in aquifers are often present as non-aqueous phase liquids (NAPL), which are long-lasting sources for groundwater contamination. The existing NAPL mass is an important parameter for the persistence of the source, but its determination is difficult. One possible detection method is based on the ideal multicomponent dissolution theory, using aqueous concentrations downstream of a fully mixed NAPL source to calculate its mass. In this publication, the applicability of this method is tested for a source size of about 5 m, using numerical methods. In contrast to fully mixed source zones, on this scale the NAPL sources are not in contact with each other, do not mix and develop independently over time. Highly soluble NAPL components can be depleted or the NAPL phase can be completely exhausted locally, while in other portions of the source zone NAPL is still present with all its components. Hence, the interpretation of the resulting aqueous concentrations downstream using the ideal dissolution theory leads to erroneous NAPL masses of several orders of magnitude in the investigated scenarios. © 2012 Springer-Verlag. Source


Christophers E.,University of Kiel
Expert Review of Dermatology | Year: 2012

Psoriasis is a common inflammatory skin disease that presents with a variety of different subtypes and disease activities. There is evidence that various forms, including pustular psoriasis, represent different entities. Genome-wide association studies revealed more than 20 susceptibility loci on various chromosomes. These are mostly linked to immune regulation and barrier formation. Immune regulation in psoriasis is complex with an emphasis on Th1-directed autoimmunity. Recently Th17 cells have become a focus of interest and are shown to be pivotal in regulating cytokine overproduction, which stimulates growth and differentiation of keratinocytes. Circumstantial evidence shows bimodal immunopathology with adaptive, as well as innate, immune pathways. The inflammatory nature of psoriasis is associated with an increased risk of comorbidities, including myocardial infarction, metabolic syndrome and reduced life expectancy. Awareness of these complications is mandatory when treating patients with psoriasis. © 2012 Expert Reviews Ltd. Source


Hartwigsen G.,University of Leipzig | Hartwigsen G.,Max Planck Institute for Human Cognitive and Brain Sciences | Hartwigsen G.,University of Kiel | Golombek T.,University of Leipzig | And 2 more authors.
Cortex | Year: 2015

Increased neural activity in left angular gyrus (AG) accompanies successful comprehension of acoustically degraded but highly predictable sentences, as previous functional imaging studies have shown. However, it remains unclear whether the left AG is causally relevant for the comprehension of degraded speech. Here, we applied transient virtual lesions to either the left AG or superior parietal lobe (SPL, as a control area) with repetitive transcranial magnetic stimulation (rTMS) while healthy volunteers listened to and repeated sentences with high- versus low-predictable endings and different noise vocoding levels. We expected that rTMS of AG should selectively modulate the predictability gain (i.e., the comprehension benefit from sentences with high-predictable endings) at a medium degradation level. We found that rTMS of AG indeed reduced the predictability gain at a medium degradation level of 4-band noise vocoding (relative to control rTMS of SPL). In contrast, the behavioral perturbation induced by rTMS changed with increased signal quality. Hence, at 8-band noise vocoding, rTMS over AG versus SPL decreased the number of correctly repeated keywords for sentences with low-predictable endings. Together, these results show that the degree of the rTMS interference depended jointly on signal quality and predictability. Our results provide the first causal evidence that the left AG is a critical node for facilitating speech comprehension in challenging listening conditions. © 2014 Elsevier Ltd. Source


Emesis and nausea are side effects induced by chemotherapy. These effects lead to enormous stress and strain on cancer patients. Further consequences may include restrictions in quality of life, cachexia or therapy avoidance. Evidence suggests that cancer patients develop the side effects of nausea and vomiting in anticipation of chemotherapy. Contextual cues such as smell, sounds or even the sight of the clinic may evoke anticipatory nausea and vomiting prior to infusion. Anticipatory nausea and vomiting are problems that cannot be solved by administration of antiemetica alone.The purpose of the proposed randomized placebo-controlled trial is to use an overshadowing technique to prevent anticipatory nausea and vomiting and to decrease the intensity and duration of post-treatment nausea and vomiting. Furthermore, the effect on anxiety, adherence and quality of life will be evaluated. Fifty-two pediatric cancer patients will be evenly assigned to two groups: an experimental group and a control group. The participants, hospital staff and data analysts will be kept blinded towards group allocation. The experimental group will receive during three chemotherapy cycles a salient piece of candy prior to every infusion, whereas the control group will receive flavorless placebo tablets. If an effectiveness of the overshadowing technique is proven, implementation of this treatment into the hospitals' daily routine will follow. The use of this efficient and economic procedure should aid a reduced need for antiemetics. Current Controlled Trials ISRCTN30242271/ Source


Chevreau H.,University of Versailles | Devic T.,University of Versailles | Salles F.,Charles Gerhardt Institute | Maurin G.,Charles Gerhardt Institute | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2013

It's all in the mix! Metal-organic frameworks (MOFs) were constructed from iron(III) trimers and mixtures of di- and tricarboxylate linkers. The dicarboxylate linker determined the size and shape of the pores in one series of materials with an interwoven structure and also enabled the introduction of different functionalities. Another mesoporous iron(III) MOF based on hybrid supertetrahedra had an extended β-cristobalite structure (see picture). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Gelin M.F.,TU Munich | Egorova D.,University of Kiel | Domcke W.,TU Munich
Physical Chemistry Chemical Physics | Year: 2013

The present paper is devoted to the simulation of (integral and dispersed) pump-probe signals in the nonperturbative regime for a series of material systems with multiple electronic states and excited-state absorption. We show that strong-pump strong-probe spectroscopy permits the probing of vibrational wavepackets in high-lying and/or short-lived excited electronic states with a time resolution which is not limited by the pulse durations. The field strength can be regarded as an additional experimentally controllable parameter, which can be tuned to maximize the spectroscopic information for a given material system. © 2013 the Owner Societies. Source


Pena-Alzola R.,University of Aalborg | Liserre M.,University of Aalborg | Blaabjerg F.,University of Aalborg | Sebastian R.,Spanish University for Distance Education (UNED) | And 2 more authors.
IEEE Transactions on Industrial Informatics | Year: 2014

Three-phase active rectifiers guarantee sinusoidal input currents and unity power factor at the price of a high switching frequency ripple. To adopt an LCL-filter, instead of an $L$-filter, allows using reduced values for the inductances and so preserving dynamics. However, stability problems can arise in the current control loop if the present resonance is not properly damped. Passive damping simply adds resistors in series with the LCL-filter capacitors. This simplicity is at the expense of increased losses and encumbrances. Active damping modifies the control algorithm to attain stability without using dissipative elements but, sometimes, needing additional sensors. This solution has been addressed in many publications. The lead-lag network method is one of the first reported procedures and continues being in use. However, neither there is a direct tuning procedure (without trial and error) nor its rationale has been explained. Thus, in this paper a straightforward procedure is developed to tune the lead-lag network with the help of software tools. The rationale of this procedure, based on the capacitor current feedback, is elucidated. Stability is studied by means of the root locus analysis in $z$-plane. Selecting the lead-lag network for the maximum damping in the closed-loop poles uses a simple optimization algorithm. The robustness against the grid inductance variation is also analyzed. Simulations and experiments confirm the validity of the proposed design flow. © 2005-2012 IEEE. Source


Grasner J.T.,University of Kiel | German Resuscitation Registry Working Group,Trauma Registry
Critical care (London, England) | Year: 2011

Cardiac arrest following trauma occurs infrequently compared with cardiac aetiology. Within the German Resuscitation Registry a traumatic cause is documented in about 3% of cardiac arrest patients. Regarding the national Trauma Registry, only a few of these trauma patients with cardiac arrest survive. The aim of the present study was to analyze the outcome of cardiopulmonary resuscitation (CPR) after traumatic cardiac arrest by combining data from two different large national registries in Germany. This study includes 368 trauma patients (2.8%) out of 13,329 cardiac arrest patients registered within the Resuscitation Registry, whereby 3,673 patients with a cardiac cause and successful CPR served as a cardiac control group. We further analyzed a second group of 1,535 trauma patients with cardiac arrest and early CPR registered within the Trauma Registry, whereby a total of 25,366 trauma patients without any CPR attempts served as a trauma control group. The relative frequencies from each database were used to calculate relative percentages for patients with traumatic cardiac arrest in whom resuscitation was attempted. Within the Resuscitation Registry, cardiac arrest was present in 331 patients (89.9%) when the EMS personal arrived at the scene and in 37 patients (10.1%) when cardiac arrest occurred after arrival. Spontaneous circulation could be achieved in 107 patients (29.1%). A total of 101 (27.4%) were transferred to hospital, 95 of whom (25.8%) had return of spontaneous circulation (ROSC) on admission. According to the Trauma Registry, the overall hospital mortality rate for cardiac arrest patients following trauma was 73% (n = 593 of 814). About half of the patients who were admitted alive to hospital died within 24 hours, resulting in 13% survivors within 24 hours. 7% of the patients survived until hospital discharge, and only 2% of the patients had good neurological outcome. Our present study encourages CPR attempts in cardiac arrest patients following severe trauma. When a manageable number of patients is present, the decision on whether to start CPR or not should be done liberally, using comparable criteria as in patients with cardiac etiology. In this respect, trauma management programs that restrict CPR attempts should not be encouraged. Source


Holle J.U.,University Hospital Schleswig Holstein | Laudien M.,University of Kiel | Gross W.L.,University Hospital Schleswig Holstein
Rheumatic Disease Clinics of North America | Year: 2010

Wegener's granulomatosis (WG) is characterized by granulomatous lesions and vasculitic disease manifestations. Granulomatous lesions are found in the upper and lower respiratory tract (eg, granulomatous sinusitis, orbital masses, and pulmonary granuloma), whereas vasculitic manifestations occur frequently in lung (alveolar hemorrhage) and kidney (glomerulonephritis). Vasculitis is typically associated with antineutrophil cytoplasmic antibodies (ANCA) directed against proteinase 3. WG has been traditionally associated with a poor outcome and increased mortality as documented by numerous studies; however, recent cohort studies report an improved outcome, probably a consequence of increased awareness leading to an earlier diagnosis, and to improved treatment strategies derived from evidence from controlled trials. Treatment regimens for WG, adapted to disease stage and activity, are reviewed and discussed in this article. © 2010 Elsevier Inc. Source


Huehn M.,University of Kiel
Journal of Applied Genetics | Year: 2010

The majority of published genetic maps are based on Kosambi distances or on Haldane distances. For a comparison of both map distance measures, their random variability is of particular interest. For the statistic 'variance', this paper presents a relationship between Kosambi distances and Haldane distances. The results suggest that Kosambi distances exhibit a smaller random variability. The theoretical results are applied to an experimental data set for molecular AFLP markers linked to the bolting gene of sugar beet (Beta vulgaris L.). Source


Gorb S.N.,University of Kiel | Filippov A.E.,Ukrainian Academy of Sciences
Beilstein Journal of Nanotechnology | Year: 2014

It has been recently demonstrated that adhesive tarsal setae of beetles possess material gradients along their length. These gradients presumably represent an evolutionary optimization enhancing the adaptation to rough surfaces while simultaneously preventing clusterisation of the setae by lateral collapse. The numerical experiment of the present study has clearly demonstrated that gradientbearing fibers with short soft tips and stiff bases have greater advantage in maximizing adhesion and minimizing clusterisation in multiple attachment-detachment cycles, if compared to the fibers with longer soft tips on the stiff bases and fibers with stiff tips on the soft bases. This study not only manifests the crucial role of gradients in material properties along the setae in beetle fibrillar adhesive system, but predicts that similar gradients must have been convergently evolved in various lineages of arthropods. © 2014 Gorb and Filippov. Source


Kruttgen A.,Labordiagnostisches Zentrum Dr. SteinKollegen | Rose-John S.,University of Kiel
Journal of Interferon and Cytokine Research | Year: 2012

Bacterial sepsis is one of the most frequent and dreaded causes of death in intensive care units. According to the current understanding of sepsis, bacterial components activate innate immune responses via pattern-recognition receptors that stimulate signaling pathways, thereby leading to activation of NF-κB and the release of cytokines, alarming the organism and coordinating appropriate defense mechanisms. The resulting "cytokine storm" not only restricts bacterial invasion; it also harms the host by triggering a hemodynamic collapse with a drop in blood pressure, which could lead to death. One of the cytokines released during sepsis is interleukin-6 (IL-6). Originally described as a B-cell-stimulating factor, this cytokine has since been shown to have multiple additional functions. Interestingly, there is emerging evidence of IL-6 trans-signaling in the pathogenesis of sepsis. We review recent findings and discuss whether therapeutic interference with IL-6 trans-signaling may be beneficial in this important clinical scenario. © Copyright 2012, Mary Ann Liebert, Inc. 2012. Source


Sprungmann D.,Ruhr University Bochum | Westerholt K.,Ruhr University Bochum | Zabel H.,Ruhr University Bochum | Weides M.,University of California at Santa Barbara | Kohlstedt H.,University of Kiel
Physical Review B - Condensed Matter and Materials Physics | Year: 2010

We have studied Josephson junctions with barriers prepared from the Heusler compound Cu2 MnAl. In the as-prepared state the Cu2 MnAl layers are nonferromagnetic and the critical Josephson current density jc decreases exponentially with the thickness of the Heusler layers dF. On annealing the junctions at 240°C the Heusler layers develop ferromagnetic order and we observe a dependence jc (dF) with jc strongly enhanced and weakly thickness dependent in the thickness range 7.0< dF <10.6nm. We interpret this feature as an indication of a triplet component in the superconducting pairing function generated by the specific magnetization profile inside thin Cu2 MnAl layers. © 2010 The American Physical Society. Source


Randel S.,Siemens AG | Adhikari S.,University of Kiel | Jansen S.L.,Nokia Inc.
IEEE Photonics Technology Letters | Year: 2010

In coherent optical long-haul transmission systems, orthogonal frequency-division multiplexing represents a promising modulation format. However, due to long symbol length, laser phase noise can be a major impairment. In this manuscript, the RF-pilot-based phase noise compensation scheme is analyzed and compared to conventional common-phase error compensation. It has been shown that the RF-pilot-based phase noise compensation scheme allows for a considerable increase in tolerable laser linewidth as compared to conventional common-phase error compensation at the cost of an increase in system complexity. For a 112-Gb/s transmission scheme, the tolerable linewidth is increased by a factor of ten as compared to common-phase error compensation. © 2010 IEEE. Source


Kahl W.-A.,University of Kiel | Goedert J.L.,University of Washington
Naturwissenschaften | Year: 2011

The bone-eating marine annelid Osedax consumes mainly whale bones on the deep-sea floor, but recent colonization experiments with cow bones and molecular age estimates suggesting a possible Cretaceous origin of Osedax indicate that this worm might be able grow on a wider range of substrates. The suggested Cretaceous origin was thought to imply that Osedax could colonize marine reptile or fish bones, but there is currently no evidence that Osedax consumes bones other than those of mammals. We provide the first evidence that Osedax was, and most likely still is, able to consume non-mammalian bones, namely bird bones. Borings resembling those produced by living Osedax were found in bones of early Oligocene marine flightless diving birds (family Plotopteridae). The species that produced these boreholes had a branching filiform root that grew to a length of at least 3 mm, and lived in densities of up to 40 individuals per square centimeter. The inclusion of bird bones into the diet of Osedax has interesting implications for the recent suggestion of a Cretaceous origin of this worm because marine birds have existed continuously since the Cretaceous. Bird bones could have enabled this worm to survive times in the Earth's history when large marine vertebrates other than fish were rare, specifically after the disappearance of large marine reptiles at the end-Cretaceous mass extinction event and before the rise of whales in the Eocene. © 2010 The Author(s). Source


Caliebe A.,University of Kiel
European Journal of Human Genetics | Year: 2015

Human pigmentation traits are of great interest to many research areas, from ancient DNA analysis to forensic science. We developed a gene-based predictive model for pigmentation phenotypes in a realistic target population for forensic case work from Northern Germany and compared our model with those brought forth by previous studies of genetically more heterogeneous populations. In doing so, we aimed at answering the following research questions: (1) do existing models allow good prediction of high-quality phenotypes in a genetically similar albeit more homogeneous population? (2) Would a model specifically set up for the more homogeneous population perform notably better than existing models? (3) Can the number of markers included in existing models be reduced without compromising their predictive capability in the more homogenous population? We investigated the association between eye, hair and skin colour and 12 candidate single-nucleotide polymorphisms (SNPs) from six genes. Our study comprised two samples of 300 and 100 individuals from Northern Germany. SNP rs12913832 in HERC2 was found to be strongly associated with blue eye colour (odds ratio=40.0, P<1.2 × 10-4) and to yield moderate predictive power (AUC: 77%; sensitivity: 90%, specificity: 63%, both at a 0.5 threshold for blue eye colour probability). SNP associations with hair and skin colour were weaker and genotypes less predictive. A comparison with two recently published sets of markers to predict eye and hair colour revealed that the consideration of additional SNPs with weak-to-moderate effect increased the predictive power for eye colour, but not for hair colour.European Journal of Human Genetics advance online publication, 19 August 2015; doi:10.1038/ejhg.2015.167. © 2015 Macmillan Publishers Limited Source


Weber S.,University of Gottingen | Saftig P.,University of Kiel
Development (Cambridge) | Year: 2012

Proteolytic enzymes belonging to the A Disintegin And Metalloproteinase (ADAM) family are able to cleave transmembrane proteins close to the cell surface, in a process referred to as ectodomain shedding. Substrates for ADAMs include growth factors, cytokines, chemokines and adhesion molecules, and, as such, many ADAM proteins play crucial roles in cell-cell adhesion, extracellular and intracellular signaling, cell differentiation and cell proliferation. In this Review, we summarize the fascinating roles of ADAMs in embryonic and adult tissue development in both vertebrates and invertebrates. © 2012. Published by The Company of Biologists Ltd. Source


Muff S.,University of Kiel
Nature Medicine | Year: 2016

Inflammation-associated pathways are active in intestinal epithelial cells (IECs) and contribute to the pathogenesis of colorectal cancer (CRC). Calcineurin, a phosphatase required for the activation of the nuclear factor of activated T cells (NFAT) family of transcription factors, shows increased expression in CRC. We therefore investigated the role of calcineurin in intestinal tumor development. We demonstrate that calcineurin and NFAT factors are constitutively expressed by primary IECs and selectively activated in intestinal tumors as a result of impaired stratification of the tumor-associated microbiota and toll-like receptor signaling. Epithelial calcineurin supports the survival and proliferation of cancer stem cells in an NFAT-dependent manner and promotes the development of intestinal tumors in mice. Moreover, somatic mutations that have been identified in human CRC are associated with constitutive activation of calcineurin, whereas nuclear translocation of NFAT is associated with increased death from CRC. These findings highlight an epithelial cell–intrinsic pathway that integrates signals derived from the commensal microbiota to promote intestinal tumor development. © 2016 Nature Publishing Group, a division of Macmillan Publishers Limited. All Rights Reserved. Source


Rocken C.,University of Kiel
Der Pathologe | Year: 2012

Gastric cancer is one of the most common cancers worldwide. In recent decades, major advancements in the understanding of the epidemiology, pathology and pathogenesis of gastric cancer have been witnessed. Infections with Helicobacter pylori or Epstein-Barr virus, dietary and lifestyle factors contribute to the risk of developing gastric cancer. With respect to pathogenesis at least three distinct types of gastric cancer exist, (1) proximal, (2) distal diffuse and (3) distal non-diffuse types. Genetic and epigenetic alterations are related to oncogene mutations and tumor suppressor gene inactivation. Canonical oncogenic pathways such as the WNT/β-catenin signaling pathway are de-regulated in gastric cancer. Hereditary and familial type gastric cancers are currently linked to CDH1 gene mutations and various genetic polymorphisms determining disease susceptibility. Molecular subtypes of gastric cancer have been identified which separate diffuse from intestinal type gastric cancer and are not entirely congruent with the histopathological phenotype according to Laurén but may influence chemosensitivity. Putative cancer stem cell markers of gastric cancer have been found (e.g. ADAM17, CD133, FZD7, LGR5) and correlate with patient prognosis. Thus, molecular phenotyping of gastric cancer is still in its infancy and the search for novel diagnostic, prognostic and predictive biomarkers continues. Source


Cooper D.N.,University of Cardiff | Krawczak M.,University of Kiel | Polychronakos C.,McGill University | Tyler-Smith C.,Wellcome Trust Sanger Institute | Kehrer-Sawatzki H.,University of Ulm
Human Genetics | Year: 2013

Some individuals with a particular disease-causing mutation or genotype fail to express most if not all features of the disease in question, a phenomenon that is known as 'reduced (or incomplete) penetrance'. Reduced penetrance is not uncommon; indeed, there are many known examples of 'disease-causing mutations' that fail to cause disease in at least a proportion of the individuals who carry them. Reduced penetrance may therefore explain not only why genetic diseases are occasionally transmitted through unaffected parents, but also why healthy individuals can harbour quite large numbers of potentially disadvantageous variants in their genomes without suffering any obvious ill effects. Reduced penetrance can be a function of the specific mutation(s) involved or of allele dosage. It may also result from differential allelic expression, copy number variation or the modulating influence of additional genetic variants in cis or in trans. The penetrance of some pathogenic genotypes is known to be age- and/or sex-dependent. Variable penetrance may also reflect the action of unlinked modifier genes, epigenetic changes or environmental factors. At least in some cases, complete penetrance appears to require the presence of one or more genetic variants at other loci. In this review, we summarize the evidence for reduced penetrance being a widespread phenomenon in human genetics and explore some of the molecular mechanisms that may help to explain this enigmatic characteristic of human inherited disease. © 2013 The Author(s). Source


Vanden Berghe T.,Inflammation Research Center | Vanden Berghe T.,Ghent University | Linkermann A.,University of Kiel
Kidney International | Year: 2015

Necrosis is not only a regulated process, it is an interconnected molecular network allowing different genetically encoded forms that are more or less immunogenic. Zhao et al. elegantly illustrate this concept, underscore the need for combination therapy to successfully interfere with regulated necrosis, and identify the role of regulated necrosis in the pathophysiology of remote lung injury. © 2015 International Society of Nephrology. Source


Meyer-Lueckel H.,RWTH Aachen | Wierichs R.J.,RWTH Aachen | Schellwien T.,University of Kiel | Paris S.,Charite - Medical University of Berlin
Caries Research | Year: 2015

The aim of this double-blind, randomized, cross-over in situ study was to compare the remineralizing effects induced by the application of casein phosphopeptide-stabilized amorphous calcium phosphate complexes (CPP-ACP)-containing cream (without fluoride) after the use of fluoride toothpaste with the prolonged use of fluoride toothpaste on enamel caries lesions in situ. During each of three experimental legs of 4 weeks, 13 participants wore intra-oral mandibular appliances with 8 pre-demineralized bovine enamel specimens in the vestibular flanges mimicking either 'easily cleanable' or 'proximal' surfaces (n = 312). The three randomly allocated treatments were as follows: (1) application of CPP-ACP-containing cream (GC Tooth Mouse, non-fluoride) after the use of fluoride toothpaste (1,400 ppm NaF; TM), (2) prolonged application of fluoride toothpaste (1,400 ppm NaF; positive control, PC) and (3) prolonged application of fluoride-free toothpaste (negative control, NC). Additionally, one of each of the two flanges was brushed twice daily with the respective toothpaste. The differences in integrated mineral loss as assessed by transversal microradiography were calculated between values before and after the in situ period. Changes in mineral loss were analysed for those pairs of subgroups differing in only one of the three factors (intervention, brushing and position). The PC treatment induced a significantly higher mineral gain compared with the TM and NC treatments. No significant differences between TM and NC for both positions were observed. In conclusion, the additional use of a CPP-ACP-containing cream seems to be less efficacious in remineralizing caries lesions than the prolonged application of fluoride toothpaste. © 2014 S. Karger AG, Basel. Source


Hanewinkel R.,Institute for Therapy and Health Research | Hanewinkel R.,University of Kiel | Isensee B.,Institute for Therapy and Health Research
Preventive Medicine | Year: 2015

Objective: Little is known about risk factors that are associated with e-cigarette use in adolescents. Methods: Multilevel mixed-effects regressions were performed to assess the relationship between factors that might be associated with e-cigarette, conventional cigarette and dual use in a cohort of 2693 German adolescents (mean age = 12.5 years; SD = 0.6). Risk factors were assessed in October 2010 and life time e-cigarette and conventional cigarette use were assessed 26. months later. Results: Use of e-cigarettes as well as use of conventional cigarette and dual use were associated with higher sensation seeking scores, and higher odds of having friends and parents who smoke conventional cigarettes, with conventional cigarette use additionally with male gender, being older, having higher odds of siblings who smoke conventional cigarettes, and less likely for adolescents who attend a Gymnasium, secondary school with a strong emphasis on academic learning. The use of conventional cigarettes at baseline did not predict e-cigarette use at follow-up. Lifetime prevalence of e-cigarette use was 4.7%, of conventional cigarette use 18.4%. A quarter of e-cigarette users (23.8%) never smoked a conventional cigarette. Discussion: Data indicate that e-cigarette and conventional cigarette use share many but not all risk factors. E-cigarettes could counteract the process of denormalization of smoking. © 2015 Elsevier Inc. Source


Shin D.-H.,Hannam University | Hassink R.,University of Kiel
Regional Studies | Year: 2011

Shin D.-H. and Hassink R. Cluster life cycles: the case of the shipbuilding industry cluster in South Korea, Regional Studies. Although South Korean academics and policy-makers have applied industrial districts, regional innovation systems and clusters both to study and promote regional economic development, these concepts have little power to explain the changing economic landscape over time. This paper tackles this question with the help of the concept of cluster life cycle and shipbuilding as a case. It concludes that the cluster life cycle concept is useful for analysing and explaining spatial industrial dynamics in Korea, but the distinction between industry life cycle and cluster life cycle is not very relevant in the case of shipbuilding. © 2011 Copyright Regional Studies Association. Source


Rosenstiel P.,University of Kiel
Current Opinion in Gastroenterology | Year: 2013

Purpose of review: Recent advances in molecular techniques have enabled a deep view into the structure and function of the host's immune system and the stably associated commensal intestinal flora. This review outlines selected aspects of the interplay of innate immune recognition and effectors that shape the ecological niches for the intestinal microbiota. RECENT FINDINGS: Several studies have demonstrated a pivotal role of innate immune receptor pathways (NOD-like receptors and Toll-like receptors) for the maintenance of microbial communities in the gut. Genetic deficiencies in these pathways have been associated with increased susceptibility to inflammation that in animal models can be transmitted via direct contact or by stool transplantation in the absence of abundant pathogens. SUMMARY: The genetic architecture of the human host shapes the diversity and function of its stably associated intestinal microflora. Innate immune receptors such as NOD2 or the inflammasome component NOD-like receptor, pyrin-domain containing 6 play a major role in licensing the microbiota under physiological conditions. Understanding the symbiotic interplay in the intestinal tract should help develop procedures and therapeutic interventions aiming at the identification and restoration of disturbed microbiota states. Indeed, these states may be the missing trigger factor for the manifestation of a multitude of civilization disorders including inflammatory bowel disease and gastrointestinal cancer. Copyright © Lippincott Williams & Wilkins. Source


Schwarz T.,University of Kiel
Journal of Investigative Dermatology | Year: 2010

Immunosuppression induced by solar UVR is regarded as one of the major negative impacts of sunlight on human health. Despite this immunosuppression, bacterial superinfections are rarely observed after UVR exposure. A possible explanation for this seeming paradox may be that although it suppresses T-cell-mediated immune reactions, UVR induces the release of cutaneous antimicrobial peptidesan essential component of the innate immune system. The sunshine vitamin, vitamin D, also appears to be involved, as UVR suppresses the adaptive but induces the innate immune response. T cells in the skin are the critical cellular mediators of the vast majority of inflammatory dermatoses, and thus probably more harmful than beneficial. Hence, it is tempting to speculate that a certain and constant level of immunosuppression by physiological UVR doses might be beneficial, taming overshooting immune reactions. At the same time, by inducing antimicrobial peptides, these low UVR doses may foster the antibacterial defense. Thus, suppression of the adaptive and induction of the innate immune system by UVR may be components of a physiological protection process. These insights might have effect on the future recommendations for daily sun protection. © 2010 The Society for Investigative Dermatology. Source


Green J.R.,Novartis | Guenther A.,University of Kiel
Critical Reviews in Oncology/Hematology | Year: 2011

Bisphosphonates (BPs) are antiresorptive agents that block pathologic bone resorption by inhibiting osteoclast function and later inducing osteoclast apoptosis. These agents localize to bone and break the vicious cycle of bone resorption that results from cross-stimulation between cancer cells and the bone remodeling cells, thereby reducing cancer-induced osteolysis and the tumor burden in bone. Thus nitrogen-containing BPs (N-BPs) have well established clinical benefits in the treatment of bone metastases from solid tumors and bone lesions from multiple myeloma. Preclinical data indicate that N-BPs, especially zoledronic acid (ZOL), can exert antimyeloma activity both in vitro and in vivo. Studies show that N-BPs can inhibit multiple intracellular processes essential for cancer cell proliferation and invasion and induce apoptosis. Furthermore, clinically relevant doses of N-BPs inhibit tumor-associated angiogenesis and can modulate macrophage phenotype in vivo, which is likely to contribute to anticancer effects. © 2011 Elsevier Ireland Ltd. Source


McCord J.,University of Kiel | Mangin S.,CNRS Jean Lamour Institute
Physical Review B - Condensed Matter and Materials Physics | Year: 2013

The temperature and time dependence of exchange bias for as-deposited Ni81Fe19-NiO films is studied. Using various cooling and measurement protocols, different contributions to the exchange anisotropy are separated. Depending on the cooling procedure, a strong increase or a controlled reversal of sign of exchange bias field is achieved at lower temperatures far away from the antiferromagnetic blocking temperature. The behavior is explained in terms of antiferromagnetic grain instability and the influence of the interfacial spin structure, the latter freezing at very low temperatures. © 2013 American Physical Society. Source


Type 1 diabetes mellitus (T1D) is considered a classical autoimmune disease which commonly starts during childhood but may appear later in adulthood in a proportion of 30-40% of affected individuals. Its development is based on a combination of a genetic predisposition and autoimmune processes that result in gradual destruction of the β-cells of the pancreas and cause absolute insulin deficiency. Evidence for an autoimmune origin of T1D results from measurable islet β-cell autoantibody directed against various autoantigens such as proinsulin or insulin itself, glutamic acid decarboxylase 65, the islet tyrosine phosphatase IA- 2, and the islet-specific glucose-6-phosphatase catalytic subunit-related protein. In addition, T-cell lines with specificity for insulin or glutamic acid decarboxylase have been identified within peripheral blood lymphocytes. Importantly, in most instances the pathogenesis of T1D comprises a slowly progressive destruction of β-cell tissue in the pancreas preceded by several years of a prediabetic phase where autoimmunity has already developed but with no clinically apparent insulin dependency. Unless immunological tolerance to pancreatic autoantigens is re-established, diabetes treated by islet cell transplantation or stimulation/regeneration of endogenous β-cells would remain a chronic disease secondary to immune suppression related morbidity. Hence, if islet cell tolerance could be re-induced, a major clinical hurdle to curing diabetes by islet cell neogenesis may be overcome. Targeted immunotherapies are currently explored in a variety of clinical studies and hold great promise for causative treatment to readjust the underlying immunologic imbalance with the goal to cure the disease. This chapter will outline possible treatment options to stop or reverse the β-cell-specific autoimmune and inflammatory process within pancreatic islets. Special emphasis is given to stem cells of embryonic, mesenchymal, and haematopoietic origin, which, besides their use for regenerative purposes, possess potent immunomodulatory functions and thus have the potential to suppress the autoimmune response. At the end of this chapter we will introduce a novel type of in vitro modified monocytes with immunosuppressive and anti-inflammatory properties. These tolerogenic monocytes provide a feasible option to be used as autologous cellular transplants to halt autoimmunity and to protect still viable β-cells within Langerhans islets. © Springer Science+Business Media B.V. 2010. Source


Volatile anaesthetic agents have been used in millions of patients around the world and have proved to be both well tolerated and efficient. In recent years, cardioprotective properties of these drugs have been demonstrated unequivocally in numerous experimental investigations, but the beneficial effects of volatile anaesthetics in daily clinical practice are still under debate. In order to elucidate their cardioprotective properties in an unbiased way, the STAIR (Stroke Therapy Academic Industry Roundtable Preclinical Recommendation) criteria proposed as a framework for researchers in the field of neuroprotection can be applied to research conducted in the field of cardioprotection by volatile anaesthetics. All STAIR criteria have already been clearly fulfilled when all experimental and clinical studies are considered. Specifically, a dose-response pattern has been found with a minimal alveolar concentration value and a ceiling effect; volatile anaesthetics show two distinct therapeutic windows after application; important outcome measures such as hospital length of stay have been addressed; and multiple species have been studied by different independent groups of researchers who were largely able to reproduce their findings. Given the numerous confounding factors capable of attenuating or even abolishing the cardioprotective properties of volatile anaesthetics in laboratory investigations, the positive effects found in the majority of clinical trials point to the fact that the cardioprotective effects exerted by volatile anaesthetics are robust and triggered by interactions with several distinct cellular and subcellular targets, thereby providing multiplication and reiteration. The available evidence indicates that volatile anaesthetic agents should be used routinely in clinical practice in order to claim an extra benefit for our patients 'free of charge'. © 2011 Copyright European Society of Anaesthesiology. Source


Haie-Meder C.,Institute Gustave Roussy | Siebert F.-A.,University of Kiel | Potter R.,Medical University of Vienna
Radiotherapy and Oncology | Year: 2011

Brachytherapy has consistently provided a very conformal radiation therapy modality. Over the last two decades this has been associated with significant improvements in imaging for brachytherapy applications (prostate, gynecology), resulting in many positive advances in treatment planning, application techniques and clinical outcome. This is emphasized by the increased use of brachytherapy in Europe with gynecology as continuous basis and prostate and breast as more recently growing fields. Image guidance enables exact knowledge of the applicator together with improved visualization of tumor and target volumes as well as of organs at risk providing the basis for very individualized 3D and 4D treatment planning. In this commentary the most important recent developments in prostate, gynecological and breast brachytherapy are reviewed, with a focus on European recent and current research aiming at the definition of areas for important future research. Moreover the positive impact of GEC-ESTRO recommendations and the highlights of brachytherapy physics are discussed what altogether presents a full overview of modern image guided brachytherapy. An overview is finally provided on past and current international brachytherapy publications focusing on "Radiotherapy and Oncology". These data show tremendous increase in almost all research areas over the last three decades strongly influenced recently by translational research in regard to imaging and technology. In order to provide high level clinical evidence for future brachytherapy practice the strong need for comprehensive prospective clinical research addressing brachytherapy issues is high-lighted. © 2011 Elsevier Ireland Ltd. All rights reserved. Source


Weng D.,University of Kiel
The International journal of oral & maxillofacial implants | Year: 2011

The vertical location of the implant-abutment connection influences the subsequent reaction of the peri-implant bone. It is not known, however, whether any additional influence is exerted by different microgap configurations. Therefore, the radiographic bone reactions of two different implant systems were monitored for 6 months. In eight mongrel dogs, two implants with an internal Morse-taper connection (INT group) were placed on one side of the mandible; the contralateral side received two implants with an external-hex connection (EXT group). On each side, one implant was aligned at the bone level (equicrestal) and the second implant was placed 1.5 mm subcrestal. Healing abutments were placed 3 months after submerged healing, and the implants were maintained for another 3 months without prosthetic loading. At implant placement and after 1, 2, 3, 4, 5, and 6 months, standardized radiographs were obtained, and peri-implant bone levels were measured with regard to microgap location and evaluated statistically. All implants osseointegrated clinically and radiographically. The overall mean bone loss was 0.68 ± 0.59 mm in the equicrestal INT group, 1.32 ± 0.49 mm in the equicrestal EXT group, 0.76 ± 0.49 mm in the subcrestal INT group, and 1.88 ± 0.81 mm in the subcrestal EXT group. The differences between the INT and EXT groups were statistically significant (paired t tests). The first significant differences between the internal and external groups were seen at month 1 in the subcrestal groups and at 3 months in the equicrestal groups. Bone loss was most pronounced in the subcrestal EXT group. Within the limits of this study, different microgap configurations can cause different amounts of bone loss, even before prosthetic loading. Subcrestal placement of a butt-joint microgap design may lead to more pronounced radiographic bone loss. Source


Jansen K.,University of Kiel | Zhang H.,Bank Street Group
Journal of Computer and System Sciences | Year: 2012

In this paper we propose an approximation algorithm for scheduling malleable tasks with precedence constraints. Based on an interesting model for malleable tasks with continuous processor allotments by Prasanna and Musicus (1991, 1994, 1996) [23-25], we define two natural assumptions for malleable tasks: the processing time of any malleable task is non-increasing in the number of processors allotted, and the speedup is concave in the number of processors. We show that under these assumptions the work function of any malleable task is non-decreasing in the number of processors and is convex in the processing time. Furthermore, we propose a two-phase approximation algorithm for the scheduling problem. In the first phase we solve a linear program to obtain a fractional allotment for all tasks. By rounding the fractional solution, each malleable task is assigned a number of processors. In the second phase a variant of the list scheduling algorithm is employed. By choosing appropriate values of the parameters, we show (via a nonlinear program) that the approximation ratio of our algorithm is at most 100/63+100(6469+13)/5481≈3.291919. We also show that our result is asymptotically tight. © 2011 Elsevier Inc. All rights reserved. Source


Block D.,University of Kiel | Miloch W.J.,University of Oslo
Plasma Physics and Controlled Fusion | Year: 2015

The role of wake effects in the charging of dust grains by plasmas with subsonic and supersonic ion flows is studied with numerical simulations. Significant ion focusing which is common for supersonic flows is also observed for subsonic regimes. In both regimes, the charge on a downstream grain aligned with the flow depends linearly on the intergrain distance. For subsonic flows and systems with several grains, the complex ion dynamics can lead to significant modifications of the charge on grains located close to the boundary of a dust lattice and the charge distribution on the grains depends on the detailed grain arrangement. The studies are carried out with DiP3D, a self-consistent particle-in-cell code (Miloch 2010 Plasma Phys. Control. Fusion 52 124004; Miloch and Block 2012 Phys. Plasmas 19 123703). © 2015 IOP Publishing Ltd. Source


Plieth C.,University of Kiel
Plant Signaling and Behavior | Year: 2012

Recently it was demonstrated that PO activity is switched by calcium within the typical range of apoplastic free calcium concentrations (Plieth and Vollbehr 201#, 2012, PSB 7:6). The heat stability of POs is also dependent on calcium. Here, a scenario is put forward which assigns calcium a switch-off function under heat: Peroxidases are switched off by heat stress-triggered apoplastic calcium depletion. It is assumed that this initiates apoplastic accumulation of reactive oxygen species (ROS) and eventually triggers a self-amplifying cascade of cellular events involving plasma membrane ion transport. Calcium depletioninitiated ROS accumulation (CaDIRA) may also trigger signal percolation and the formation of systemic responses to many different stress factors in plants. This hypothesis can explain some as yet unexplained observations. © 2012 Landes Bioscience. Source


Stoltenberg D.,ROWA Lack GmbH | Luning U.,University of Kiel
Organic and Biomolecular Chemistry | Year: 2013

2,6-Bis(alkenyloxy) substituted arylboronic acids can be cyclotrimerized with the help of a hexaol as a template. First, the boronic acids are assembled by boronic ester formation with hexahydroxy-bicyclo[2.2.2]octane. Next, the resulting triboronates are cyclized by ring-closing metathesis to yield trimacrocycles as diastereomeric E/Z mixtures. Catalytic hydrogenation yields a single saturated trimacrocycle. Cleavage of the boronic ester functions liberates the template and generates a macrocycle with three boronic acid functionalities in endo-orientation. Due to this preorganization, macrocycles with boronic acids in endo-positions are good receptors for polyols. The binding of carbohydrates such as fructose was compared with the uptake of the respective templates into macrocycles with two or three boronic acids in endo-orientation. © 2013 The Royal Society of Chemistry. Source


Liebau F.,University of Kiel
Zeitschrift fur Kristallographie | Year: 2011

The presence of mixed valency in unconventional superconductors is a necessary consequence of the fact that there is chemical equilibrium between the atoms of a transition element having different oxidation states. Consequently, phases described by stoichiometric formulas such as FeSe, Ba(FeAs) 2, La 2CuO 4 etc. deviate in fact from their nominal compositions. These deviations can be considered as doping by replacing some of the cationic atoms Fe II and Cu II in the conducting units by small amounts of Fe and Cu in higher, sometimes in lower oxidation state. From a consideration of the electronegativity values of the constituents of a selection of widely different unconventional superconductors and corresponding parent-compounds, it is evident that bonds between atoms of the conducting units have higher covalency than bonds between conducting units and charge reservoirs which are mixed ionic/covalent, and bonds within the charge reservoirs which are strongly ionic. In compounds without charge reservoirs, the bonds between neighbouring conducting units have van der Waals character. © by Oldenbourg Wissenschaftsverlag, München. Source


Jurgens U.,University of Kiel
Erdkunde | Year: 2012

In response to public decisions made by planners and policy-makers interest groups have been forming in order to act as a corrective to participatory processes that they do not consider sufficiently transparent. In Germany this has been occurring not only around large-scale projects that generate a lot of media attention, like the plans to upgrade and completely remodel the Central Station of Stuttgart ("Stuttgart21"). Increasingly frequently we also see this in response to local projects at the grassroots level. Discount grocery stores have not been excluded from this development. Because many discount supermarket chains are continuing to expand spatially, "enlightened" customers and affected residents increasingly feel that there is a "glut of discounters." Community action groups, ad hoc working groups and associations have formed to prevent discounters from opening new outlets or expanding old ones. Or they try to join planners and policy-makers in influencing the process of opening new outlets. New types of governance are developing in which self-help groups are able to give spontaneous and competent answers on short notice to questions that had never before been asked by planners. The fact that there are other coalitions of interest groups that, e.g., try to prevent a discounter from moving out of their local neighborhood, reveals the diversity of peoples' reactions to developments in discounting. Various examples from Schleswig-Holstein (Germany's northernmost province) will be used to show the motivations guiding the citizens' groups. How elitist or "citizen-centered" are their actions? What is their legitimation, whether inherent or self-proclaimed? And what power can they as a group of actors develop to influence planning and policy? To what extent do these groups serve to protect/preserve established types of retail trade? To what extent do other groups contrive to form "coalitions of change" together with discounters (not infrequently by means of "gifts" in the form of infrastructure), in order to put pressure on policy-makers to allow new outlets to be opened?. Source


Schnoor H.,University of Kiel
Proceedings of the International Joint Conference on Autonomous Agents and Multiagent Systems, AAMAS | Year: 2010

Alternating-time Temporal Logic (ATL) [1] is used to reason about strategic abilities of agents. Aiming at strategies that can realistically be implemented in software, many variants of ATL study a setting where strategies may only take available information into account [7]. Another generalization of ATL is Probabilistic ATL [4], where strategies achieve their goal with a certain probability. We introduce a semantics of ATL that takes into account both of these aspects. We prove that our semantics allows simulation relations similar in spirit to usual bisimulations, and has a decidable model checking problem in the case of memoryless strategies (for memory-dependent strategies the problem is undecidable). Copyright © 2010, International Foundation for Autonomous Agents and Multiagent Systems (www.ifaamas.org). All rights reserved. Source


Thalheim B.,University of Kiel
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2012

Conceptual modelling is one of the central activities in Computer Science. Conceptual models are mainly used as intermediate artifact for system construction. They are schematic descriptions of a system, a theory, or a phenomenon of an origin thus forming a model. A conceptual model is a model enhanced by concepts. The process of conceptual modelling is ruled by the purpose of modelling and the models. It is based on a number of modelling acts, on a number of correctness conditions, on modelling principles and postulates, and on paradigms of the background or substance theories. Purposes determine the (surplus) value of a model. Conceptual modelling is performed by a modeller that directs the process based on his/her experience, education, understanding, intention and attitude. Conceptual models are products that are used by other stakeholders such as programmers, learners, business users, and evaluators. Conceptual models use a language as a carrier for the modelling artifact and are restricted by the expressiveness of this carrier. This paper aims at a discussion of a general theory of modelling as a culture and an art. A general theory of modelling also considers modelling as an apprenticeship and as a technology. It is thus an art. Modelling is on of the main elements of Computer Science culture that consists of commonly accepted behaviour patterns, arts, consensus, institutions, and all other supporting means and thoughts. © 2012 Springer-Verlag. Source


Klein B.,University of California at Los Angeles | Jura M.,University of California at Los Angeles | Koester D.,University of Kiel | Zuckerman B.,University of California at Los Angeles
Astrophysical Journal | Year: 2011

We report Keck High Resolution Echelle Spectrometer data and model atmosphere analysis of two helium-dominated white dwarfs, PG1225-079 and HS2253+8023, whose heavy pollutions most likely derive from the accretion of terrestrial-type planet(esimal)s. For each system, the minimum accreted mass is 1022 g, that of a large asteroid. In PG1225-079, Mg, Cr, Mn, Fe, and Ni have abundance ratios similar to bulk Earth values, while we measure four refractory elements, Ca, Sc, Ti, and V, all at a factor of ∼2-3 higher abundance than in the bulk Earth. For HS2253+8023 the swallowed material was compositionally similar to bulk Earth in being more than 85% by mass in the major element species, O, Mg, Si, and Fe, and with abundances in the distinctive proportions of mineral oxides - compelling evidence for an origin in a rocky parent body. Including previous studies we now know of four heavily polluted white dwarfs where the measured oxygen and hydrogen are consistent with the view that the parents' bodies formed with little ice, interior to any snow line in their nebular environments. The growing handful of polluted white dwarf systems with comprehensive abundance measurements form a baseline for characterizing rocky exoplanet compositions that can be compared with bulk Earth. © 2011. The American Astronomical Society. All rights reserved. Source


Resampling of high-resolution data sets is often required for real-time applications in geosciences, e.g., interactive modeling and 3D visualization. To support interactivity and real-time computations, it is often necessary to resample the data sets to a resolution adequate to the application. Conventional resampling approaches create uniformly distributed results, which are not always the best possible solution for articular applications. I have developed a new resampling method called constrained indicator data resampling (CIDRe). This method results in irregular point distributions that are adapted to local parameter signal wavelengths of the given data. The algorithm identifies wavelength variations by analyzing gradients in the given parameter distribution. A higher oint density is ensured in areas with larger gradients than in areas with smaller gradients, and thus the resulting data set shows an irregular point distribution. A synthetic data test showed that CIDRe is able to represent a data set better than conventional resampling algorithms. In a second application, CIDRe was used to reduce the number of gravity stations for interactive 3D density modeling, in which the resulting point distribution still allows accurate interactive modeling with a minimum number of data points. © 2016 Society of Exploration Geophysicists. Source


Girven J.,University of Warwick | Gansicke B.T.,University of Warwick | Steeghs D.,University of Warwick | Koester D.,University of Kiel
Monthly Notices of the Royal Astronomical Society | Year: 2011

We present a method which uses colour-colour cuts on the Sloan Digital Sky Survey (SDSS) photometry to select white dwarfs with hydrogen-rich (DA) atmospheres without the recourse to spectroscopy. This method results in a sample of DA white dwarfs that is 95 per cent complete at an efficiency of returning a true DA white dwarf of 62 per cent. The approach was applied to SDSS Data Release 7 for objects with and without SDSS spectroscopy. This led to 4636 spectroscopicially confirmed DA white dwarfs with g≤ 19; a ~70 per cent increase compared to Eisenstein et al.'s 2006 sample. Including the photometric-only objects, we estimate a factor of 3 increase in DA white dwarfs. We find that the SDSS spectroscopic follow-up is 44 per cent complete for DA white dwarfs with Teff≳ 8000K. We further cross-correlated the SDSS sample with Data Release 8 of the UKIRT (United Kingdom Infrared Telescope) Infrared Deep Sky Survey (UKIDSS) Large Area Survey. The spectral energy distributions (SED) of both subsets, with and without SDSS spectroscopy, were fitted with white dwarf models to determine the fraction of DA white dwarfs with low-mass stellar companions or dusty debris discs via the detection of excess near-infrared emission. From the spectroscopic sample we find that 2.0 per cent of white dwarfs have an excess consistent with a brown dwarf type companion, with a firm lower limit of 0.8 per cent. From the white dwarfs with photometry only, we find that 1.8 per cent are candidates for having brown dwarf companions. Similarly, both samples show that ~1 per cent of white dwarfs are candidates for having a dusty debris disc. © 2011 The Authors. Monthly Notices of the Royal Astronomical Society © 2011 RAS. Source


Melendez I.,Curtin University Australia | Grice K.,Curtin University Australia | Schwark L.,Curtin University Australia | Schwark L.,University of Kiel
Scientific Reports | Year: 2013

The occurrence of intact sterols has been restricted to immature Cretaceous (∼125â..Ma) sediments with one report from the Late Jurassic (∼165â..Ma). Here we report the oldest occurrence of intact sterols in a Crustacean fossil preserved for ca. 380â.Ma within a Devonian concretion. The exceptional preservation of the biomass is attributed to microbially induced carbonate encapsulation, preventing full decomposition and transformation thus extending sterol occurrences in the geosphere by 250â..Ma. A suite of diagenetic transformation products of sterols was also identified in the concretion, demonstrating the remarkable coexistence of biomolecules and geomolecules in the same sample. Most importantly the original biolipids were found to be the most abundant steroids in the sample. We attribute the coexistence of steroids in a diagenetic continuum-ranging from stenols to triaromatic steroids-to microbially mediated eogenetic processes. Source