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Johann Christoph Friedrich von Schiller was a German poet, philosopher, historian, and playwright. During the last seventeen years of his life , Schiller struck up a productive, if complicated, friendship with already famous and influential Johann Wolfgang von Goethe. They frequently discussed issues concerning aesthetics, and Schiller encouraged Goethe to finish works he left as sketches. This relationship and these discussions led to a period now referred to as Weimar Classicism. They also worked together on Xenien, a collection of short satirical poems in which both Schiller and Goethe challenge opponents to their philosophical vision. Wikipedia.

Sudakaran S.,Max Planck Institute for Chemical Ecology | Salem H.,Max Planck Institute for Chemical Ecology | Kost C.,Max Planck Institute for Chemical Ecology | Kost C.,Friedrich - Schiller University of Jena | Kaltenpoth M.,Max Planck Institute for Chemical Ecology
Molecular Ecology | Year: 2012

Symbiotic bacteria often play an essential nutritional role for insects, thereby allowing them to exploit novel food sources and expand into otherwise inaccessible ecological niches. Although many insects are inhabited by complex microbial communities, most studies on insect mutualists so far have focused on single endosymbionts and their interactions with the host. Here, we provide a comprehensive characterization of the gut microbiota of the red firebug (Pyrrhocoris apterus, Hemiptera, Pyrrhocoridae), a model organism for physiological and endocrinological research. A combination of several culture-independent techniques (454 pyrosequencing, quantitative PCR and cloning/sequencing) revealed a diverse community of likely transient bacterial taxa in the mid-gut regions M1, M2 and M4. However, the completely anoxic M3 region harboured a distinct microbiota consisting of facultative and obligate anaerobes including Actinobacteria (Coriobacterium glomerans and Gordonibacter sp.), Firmicutes (Clostri-dium sp. and Lactococcus lactis) and Proteobacteria (Klebsiella sp. and a previously undescribed Rickettsiales bacterium). Characterization of the M3 microbiota in different life stages of P. apterus indicated that the symbiotic bacterial community is vertically transmitted and becomes well defined between the second and third nymphal instar, which coincides with the initiation of feeding. Comparing the mid-gut M3 microbial communities of P. apterus individuals from five different populations and after feeding on three different diets revealed that the community composition is qualitatively and quantitatively very stable, with the six predominant taxa being consistently abundant. Our findings suggest that the firebug mid-gut microbiota constitutes a functionally important and possibly coevolved symbiotic community. see also the Perspective by Fukatsu. © 2012 Blackwell Publishing Ltd.

Williams-Carrier R.,University of Oregon | Zoschke R.,University of Oregon | Belcher S.,University of Oregon | Pfalz J.,Friedrich - Schiller University of Jena | Barkan A.,University of Oregon
Plant Physiology | Year: 2014

Chloroplast transcription in land plants relies on collaboration between a plastid-encoded RNA polymerase (PEP) of cyanobacterial ancestry and a nucleus-encoded RNA polymerase of phage ancestry. PEP associates with additional proteins that are unrelated to bacterial transcription factors, many of which have been shown to be important for PEP activity in Arabidopsis (Arabidopsis thaliana). However, the biochemical roles of these PEP-associated proteins are not known. We describe phenotypes conditioned by transposon insertions in genes encoding the maize (Zea mays) orthologs of five such proteins: ZmPTAC2, ZmMurE, ZmPTAC10, ZmPTAC12, and ZmPRIN2. These mutants have similar ivory/virescent pigmentation and similar reductions in plastid ribosomes and photosynthetic complexes. RNA gel-blot and microarray hybridizations revealed numerous changes in plastid transcript populations, many of which resemble those reported for the orthologous mutants in Arabidopsis. However, unanticipated reductions in the abundance of numerous transfer RNAs (tRNAs) dominated the microarray data and were validated on RNA gel blots. The magnitude of the deficiencies for several tRNAs was similar to that of the most severely affected messenger RNAs, with the loss of trnL-UAA being particularly severe. These findings suggest that PEP and its associated proteins are critical for the robust transcription of numerous plastid tRNAs and that this function is essential for the prodigious translation of plastid-encoded proteins that is required during the installation of the photosynthetic apparatus. © 2014 American Society of Plant Biologists. All rights reserved.

van Dyk S.,Friedrich - Schiller University of Jena
Journal of Aging Studies | Year: 2016

When it comes to old age, we are witnessing almost revolutionary changes at the present time. After decades of ignorance and lack of public interest, old age has fundamentally been re-negotiated. A diverse range of authors have diagnosed the growing bifurcation of old age into a rather independent and capable Third Age and a deep old Fourth Age that is characterized by sickness, frailty and dependency. Against this backdrop, many gerontologists claim that the so-called young-old are praised and valued for their (ongoing) "sameness" in terms of midlife-norms and capabilities, whereas the oldest old are increasingly excluded from humanity by radical "othering". Taking up this diagnosis, the article elaborates on this growing polarization within later life: Based on empirical research on the re-negotiation of old age in Germany, this contribution argues that the juxtaposition of "sameness" and "otherness" obscures the true character of the polarization, particularly with regard to the social role of the Third Age. Instead of sameness and otherness, we rather witness different processes of othering, with the young-old being valued as the other and the oldest old being disdained as the other. Despite the existence of profound critical analyses of the abjection associated with the Fourth Age as well as a considerable amount of literature on old age activation and the new role of the young-old, the specific point of this article's concern-the othering of the Third Age-has been completely neglected. The article discusses the reasons for this gap in more detail and will indicate to what extent concepts from Postcolonial Studies may help us to understand the dual process of othering-glorification and abjection. © 2016 Elsevier Inc.

Said B.,Friedrich - Schiller University of Jena
Studies in Conflict and Terrorism | Year: 2012

This article deals with militant Islamist hymns (anasheed jihadiya; in the following simply referred to as nasheeds) as an expression of jihadist culture. In this context jihadism is regarded as a militant fraction within the Salafi movement, with which it shares goals but not means. 1 The jihadist culture as a tool to create a common jihadist identity and to mobilize new recruits is probably as important as its ideology is. In 2004 Marc Sageman made the following remarks in his book Understanding Terror Networks: "... social bonds play a more important role in the emergence of the global Salafi jihad than ideology." 2 The history of nasheeds will be traced back as well as an analysis of its contents and usage will be given. © Taylor & Francis Group, LLC.

Janssen R.,Uppsala University | Damen W.G.M.,Friedrich - Schiller University of Jena | Budd G.E.,Uppsala University
BMC Developmental Biology | Year: 2012

Background: A hallmark of Drosophila segmentation is the stepwise subdivision of the body into smaller and smaller units, and finally into the segments. This is achieved by the function of the well-understood segmentation gene cascade. The first molecular sign of a segmented body appears with the action of the pair rule genes, which are expressed as transversal stripes in alternating segments. Drosophila development, however, is derived, and in most other arthropods only the anterior body is patterned (almost) simultaneously from a pre-existing field of cells; posterior segments are added sequentially from a posterior segment addition zone. A long-standing question is to what extent segmentation mechanisms known from Drosophila may be conserved in short-germ arthropods. Despite the derived developmental modes, it appears more likely that conserved mechanisms can be found in anterior patterning. Results: Expression analysis of pair rule gene orthologs in the blastoderm of the pill millipede Glomeris marginata (Myriapoda: Diplopoda) suggests that these genes are generally involved in segmenting the anterior embryo. We find that the Glomeris pairberry-1 (pby-1) gene is expressed in a pair rule pattern that is also found in insects and a chelicerate, the mite Tetraynchus urticae. Other Glomeris pair rule gene orthologs are expressed in double segment wide domains in the blastoderm, which at subsequent stages split into two stripes in adjacent segments. Conclusions: The expression patterns of the millipede pair rule gene orthologs resemble pair rule patterning in Drosophila and other insects, and thus represent evidence for the presence of an ancestral pair rule-like mechanism in myriapods. We discuss the possibilities that blastoderm patterning may be conserved in long-germ and short-germ arthropods, and that a posterior double segmental mechanism may be present in short-germ arthropods. © 2012 Janssen et al.; licensee BioMed Central Ltd.

Schilling N.,Friedrich - Schiller University of Jena | Carrier D.R.,University of Utah
Journal of Experimental Biology | Year: 2010

The body axis plays a central role in tetrapod locomotion. It contributes to the work of locomotion, provides the foundation for the production of mechanical work by the limbs, is central to the control of body posture, and integrates limb and trunk actions. The epaxial muscles of mammals have been suggested to mobilize and globally stabilize the trunk, but the timing and the degree to which they serve a particular function likely depend on the gait and the vertebral level. To increase our understanding of their function, we recorded the activity of the m. multifidus lumborum and the m. Iongissimus thoracis et lumborum at three craniocaudal levels in dogs while they walked, trotted and galloped. The level of muscle recruitment was significantly higher during trotting than during walking, but was similar during trotting and galloping. During walking, epaxial muscle activity is appropriate to produce lateral bending and resist long-axis torsion of the trunk and forces produced by extrinsic limb muscles. During trotting, they also stabilize the trunk in the sagittal plane against the inertia of the center of mass. Muscle recruitment during galloping is consistent with the production of sagittal extension. The sequential activation along the trunk during walking and galloping is in accord with the previously observed traveling waves of lateral and sagittal bending, respectively, while synchronized activity during trotting is consistent with a standing wave of trunk bending. Thus, the cranio-caudal recruitment patterns observed in dogs resemble plesiomorphic motor patterns of tetrapods. In contrast to other tetrapods, mammals display bilateral activity during symmetrical gaits that provides increased sagittal stability and is related to the evolution of a parasagittal limb posture and greater sagittal mobility. © 2010. Published by The Company of Biologists Ltd.

Abel E.D.,University of Utah | Doenst T.,Friedrich - Schiller University of Jena
Cardiovascular Research | Year: 2011

Cardiac hypertrophy is a stereotypic response of the heart to increased workload. The nature of the workload increase may vary depending on the stimulus (repetitive, chronic, pressure, or volume overload). If the heart fully adapts to the new loading condition, the hypertrophic response is considered physiological. If the hypertrophic response is associated with the ultimate development of contractile dysfunction and heart failure, the response is considered pathological. Although divergent signalling mechanisms may lead to these distinct patterns of hypertrophy, there is some overlap. Given the close relationship between workload and energy demand, any form of cardiac hypertrophy will impact the energy generation by mitochondria, which are the key organelles for cellular ATP production. Significant changes in the expression of nuclear and mitochondrially encoded transcripts that impact mitochondrial function as well as altered mitochondrial proteome composition and mitochondrial energetics have been described in various forms of cardiac hypertrophy. Here, we review mitochondrial alterations in pathological and physiological hypertrophy. We suggest that mitochondrial adaptations to pathological and physiological hypertrophy are distinct, and we shall review potential mechanisms that might account for these differences. © 2010 The Author.

Catalgol B.,Marmara University | Grune T.,Friedrich - Schiller University of Jena
Progress in Molecular Biology and Translational Science | Year: 2012

Proteasomal degradation of damaged proteins is involved in the pathogenesis of many neurodegenerative diseases including Alzheimer's, Parkinson's, Huntington's, stroke, and amyotrophic lateral sclerosis. A malfunction of the proteasomal activity may be the result or the consequence of protein aggregation, which is a key process for most neurodegenerative diseases. Because of the widespread aspects of the proteasomal involvement in the progression of these diseases, many studies are focused on this research. © 2012 Elsevier Inc.

Janssen R.,Uppsala University | Budd G.E.,Uppsala University | Damen W.G.M.,Friedrich - Schiller University of Jena
Developmental Biology | Year: 2011

Segmentation, i.e. the subdivision of the body into serially homologous units, is one of the hallmarks of the arthropods. Arthropod segmentation is best understood in the fly Drosophila melanogaster. But different from the situation in most arthropods in this species all segments are formed from the early blastoderm (so called long-germ developmental mode). In most other arthropods only the anterior segments are formed in a similar way (so called short-germ developmental mode). Posterior segments are added one at a time or in pairs of two from a posterior segment addition zone. The segmentation mechanisms are not universally conserved among arthropods and only little is known about the genetic patterning of the anterior segments. Here we present the expression patterns of the insect head patterning gene orthologs hunchback (hb), orthodenticle (otd), buttonhead-like (btdl), collier (col), cap-n-collar (cnc) and crocodile (croc), and the trunk gap gene Krüppel (Kr) in the myriapod Glomeris marginata. Conserved expression of these genes in insects and a myriapod suggests that the anterior segmentation system may be conserved in at least these two classes of arthropods. This finding implies that the anterior patterning mechanism already existed in the last common ancestor of insects and myriapods. © 2011 Elsevier Inc.

Martin D.,U.S. National Institutes of Health | Galisteo R.,U.S. National Institutes of Health | Molinolo A.A.,U.S. National Institutes of Health | Wetzker R.,Friedrich - Schiller University of Jena | And 2 more authors.
Cancer Cell | Year: 2011

Angioproliferative tumors induced by the Kaposi's sarcoma-associated herpesvirus (KSHV) have been successfully treated with rapamycin, which provided direct evidence of the clinical activity of mTOR inhibitors in human malignancies. However, prolonged mTOR inhibition may raise concerns in immunocompromised patients, including AIDS-Kaposi's sarcoma (KS). Here, we explored whether KSHV oncogenes deploy cell type-specific signaling pathways activating mTOR, which could be exploited to halt KS development while minimizing immune suppressive effects. We found that PI3Kγ, a PI3K isoform exhibiting restricted tissue distribution, is strictly required for signaling from the KSHV-encoded vGPCR oncogene to Akt/mTOR. Indeed, by using an endothelial-specific gene delivery system modeling KS development, we provide genetic and pharmacological evidence that PI3Kγ may represent a suitable molecular target for therapeutic intervention in KS. © 2011 Elsevier Inc.

Chakraborty P.,Leibniz Institute for Age Research | Grosse F.,Leibniz Institute for Age Research | Grosse F.,Friedrich - Schiller University of Jena
DNA Repair | Year: 2011

Human DHX9 helicase, also known as nuclear DNA helicase II (NDH II) and RNA helicase A (RHA), belongs to the SF2 superfamily of nucleic acid unwinding enzymes. DHX9 melts simple DNA-DNA, RNA-RNA, and DNA-RNA strands with a 3′-5′ polarity; despite this little is known about its substrate specificity. Here, we used partial duplex DNA consisting of M13mp18 DNA and oligonucleotide-based replication and recombination intermediates. We show that DHX9 unwinds DNA- and RNA-containing forks, DNA- and RNA-containing displacement loops (D- and R-loops), and also G-quadruplexes. With these substrates, DHX9 behaved similarly as the RecQ helicase WRN. In contrast to WRN, DHX9 melted RNA-hybrids considerably faster than the corresponding DNA-DNA strands. DHX9 preferably unwound R-loops and DNA-based G-quadruplexes indicating that these structures may be biologically relevant. DHX9 also unwound RNA-based G-quadruplexes that have been reported to occur in human transcripts. It is believed that an improper dissolution of co-transcriptionally formed D-loops, R-loops, and DNA- or RNA-based G-quadruplexes represent potential roadblocks for transcription and thereby enhance transcription associated recombination events. By unwinding these structures, DHX9 may significantly contribute to transcriptional activation and also to the maintenance of genomic stability. © 2011 Elsevier B.V.

Mackovic M.,Friedrich - Alexander - University, Erlangen - Nuremberg | Niekiel F.,Friedrich - Alexander - University, Erlangen - Nuremberg | Wondraczek L.,Friedrich - Schiller University of Jena | Spiecker E.,Friedrich - Alexander - University, Erlangen - Nuremberg
Acta Materialia | Year: 2014

We report on the use of in situ transmission electron microscopy techniques and finite element method simulations to study the influence of electron beam irradiation on the deformation behavior and mechanical properties of nanoscale amorphous silica balls. We show that, on the nanometer scale, electron beam irradiation of silica results in athermal densification and simultaneous material hardening. It is demonstrated how the amount of densification can be controlled via the irradiation dose, using specific beam current densities inside a transmission electron microscope. The electron-beam-induced densification is interpreted as the direct reason for the observed hardening effect. Finite element method simulations are used to model the mechanical response of the silica balls, confirming that the intrinsic properties (such as the Young's modulus) of amorphous silica can be tailored with the electron beam on the nanoscale. © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Losse J.,Leibniz Institute for Natural Product Research and Infection Biology | Zipfel P.F.,Leibniz Institute for Natural Product Research and Infection Biology | Zipfel P.F.,Friedrich - Schiller University of Jena | Jozsi M.,Leibniz Institute for Natural Product Research and Infection Biology
Journal of Immunology | Year: 2010

The host complement system plays an important role in protection against infections. Several human-pathogenic microbes were shown to acquire host complement regulators, such as factor H (CFH), that downregulate complement activation at the microbial surface and protect the pathogens from the opsonic and lytic effects of complement. Because CFH can also bind to host cells, we addressed the role of CFH and CFH-related proteins as adhesion ligands in host-pathogen interactions. We show that the CFH family proteins CFH, CFH-like protein 1 (CFHL1), CFH-related protein (CFHR) 1, and CFHR4 long isoform bind to human neutrophil granulocytes and to the opportunistic human-pathogenic yeast Candida albicans. Two major binding sites, one within the Nterminus and one in the C-terminus of CFH, were found to mediate binding to neutrophils. Complement receptor 3 (CD11b/ CD18; αMβ2 integrin) was identified as the major cellular receptor on neutrophils for CFH, CFHL1, and CFHR1, but not for CFHR4 long isoform. CFH and CFHR1 supported cell migration. Furthermore, CFH, CFHL1, and CFHR1 increased attachment of neutrophils to C. albicans. Adhesion of neutrophils to plasma-opsonized yeasts was reduced when CFH binding was inhibited by specific Abs or when using CFH-depleted plasma. Yeast-bound CFH and CFHR1 enhanced the generation of reactive oxygen species and the release of the antimicrobial protein lactoferrin by human neutrophils, and resulted in a more efficient killing of the pathogen. Thus, CFH and CFHR1, when bound on the surface of C. albicans, enhance antimicrobial activity of human neutrophils. Copyright © 2010 by The American Association of Immunologists, Inc.

Sutton A.M.,Friedrich - Schiller University of Jena
Algorithmica | Year: 2015

The ((Formula presented.)) EA is a simple evolutionary algorithm that is known to be efficient on linear functions and on some combinatorial optimization problems. In this paper, we rigorously study its behavior on three easy combinatorial problems: finding the 2-coloring of a class of bipartite graphs, solving a class of satisfiable 2-CNF formulas, and solving a class of satisfiable propositional Horn formulas. We prove that it is inefficient on all three problems in the sense that the number of iterations the algorithm needs to minimize the cost functions is superpolynomial with high probability. Our motivation is to better understand the influence of problem instance structure on the runtime character of a simple evolutionary algorithm. We are interested in what kind of structural features give rise to so-called metastable states at which, with probability (Formula presented.), the ((Formula presented.)) EA becomes trapped and subsequently has difficulty leaving. Finally, we show how to modify the ((Formula presented.)) EA slightly in order to obtain a polynomial-time performance guarantee on all three problems. © 2015 Springer Science+Business Media New York

Loxdale H.D.,Friedrich - Schiller University of Jena | Loxdale H.D.,Max Planck Institute for Chemical Ecology
Ecological Entomology | Year: 2010

1. The insects represent around 75% of the world's fauna and as such provide especially good examples of the evolutionary process in action, aided by their often rapid generation time and high rate of reproduction. 2. Here, I review some of the main mechanisms of mutational, ecological, and evolutionary change in insects. All those described, whether allo- para- or sympatric, involve changes in the genome or in behaviour that may ultimately isolate newly changed individuals from the parental population/s. They include: loss of sexuality by various means, including (potentially) mutation of the gene/s controlling sexuality; karyotypic changes, both in terms of the number of chromosomes, translocation, polyploidy, and hybridisation; host shifts as pre- and post-zygotic isolating mechanisms, and in asexuals such as aphids, 'divergence hitchhiking' around key quantitative trait loci (QTL), and in moths, selection acting at a few linkage groups; enzyme-based adaptive changes; sex and contact pheromone-based isolating mechanisms; phenotypic plastic changes; and epigenetic changes. These last such changes are brought about by stress inducers, and may be transgenerational in their effects. 3. Of the above mechanisms, probably chromosomal changes and host shifts represent the commonest mechanisms. © 2010 The Royal Entomological Society.

Pohnert G.,Friedrich - Schiller University of Jena
Journal of Plankton Research | Year: 2010

Plankton chemical ecology, the discipline investigating the role of ecological interactions that are influenced by chemicals, is a quite mature research field. Nevertheless, several conceptual problems arise if the function and evolution of chemical signalling in the sea is concerned. Modelling does not always allow prediction of an ecological role of metabolites, and bioassays that address entire plankton communities are rare. It is argued here that a comprehensive inventory of plankton signals and large scale bioassays addressing the role of selected metabolites in whole plankton communities might lead to a further understanding of infochemicals beyond laboratory systems.

Zaske R.,Institute of Psychology | Volberg G.,Institute of Psychology | Kovacs G.,Friedrich - Schiller University of Jena | Schweinberger S.R.,Institute of Psychology
Journal of Neuroscience | Year: 2014

Listeners can recognize familiar human voices from variable utterances, suggesting the acquisition of speech-invariant voice representations during familiarization. However, the neurocognitive mechanisms mediating learning and recognition of voices from natural speech are currently unknown. Using electrophysiology, we investigated how representations are formed during intentional learning of initially unfamiliar voices that were later recognized among novel voices. To probe the acquisition of speech-invariant voice representations, we compared a "same sentence" condition, in which speakers repeated the study utterances at test, and a "different sentence" condition. Although recognition performance was higher for same compared with different sentences, substantial voice learning also occurred for different sentences, with recognition performance increasing across consecutive study-test-cycles. During study, eventrelated potentials elicited by voices subsequently remembered elicited a larger sustained parietal positivity (~250-1400 ms) compared with subsequently forgotten voices. This difference due to memory was unaffected by test sentence condition and may thus reflect the acquisition of speech-invariant voice representations. At test, voices correctly classified as "old" elicited a larger late positive component (300 -700 ms) at Pz than voices correctly classified as "new." This event-related potential OLD/NEW effect was limited to the same sentence condition and may thus reflect speech-dependent retrieval of voices from episodic memory. Importantly, a speech-independent effect for learned compared with novel voices was found in beta band oscillations (16 -17 Hz) between 290 and 370 ms at central and right temporal sites. Our results are a first step toward elucidating the electrophysiological correlates of voice learning and recognition. © 2014 the authors.

Maas A.,Friedrich - Schiller University of Jena
Modern Physics Letters A | Year: 2013

Though being weakly interacting, QED can support bound states. In principle, this can be expected for the weak interactions in the Higgs sector as well. In fact, it has been argued long ago that there should be a duality between bound states and the elementary particles in this sector, at least in leading order in an expansion in the Higgs quantum fluctuations around its expectation value. Whether this remains true beyond the leading order is being investigated using lattice simulations, and support is found. This provides a natural interpretation of peaks in cross-sections as bound states. This would imply that (possibly very broad) resonances of Higgs and W and Z bound states could exist within the Standard Model. © World Scientific Publishing Company.

Hilditch D.,Friedrich - Schiller University of Jena
International Journal of Modern Physics A | Year: 2013

These lecture notes accompany two classes given at the NRHEP2 school. In the first lecture I introduce the basic concepts used for analyzing well-posedness, that is the existence of a unique solution depending continuously on given data, of evolution partial differential equations. I show how strong hyperbolicity guarantees well-posedness of the initial value problem. Symmetric hyperbolic systems are shown to render the initial boundary value problem well-posed with maximally dissipative boundary conditions. I discuss the Laplace-Fourier method for analyzing the initial boundary value problem. Finally, I state how these notions extend to systems that are first-order in time and second-order in space. In the second lecture I discuss the effect that the gauge freedom of electromagnetism has on the PDE status of the initial value problem. I focus on gauge choices, strong-hyperbolicity and the construction of constraint preserving boundary conditions. I show that strongly hyperbolic pure gauges can be used to build strongly hyperbolic formulations. I examine which of these formulations is additionally symmetric hyperbolic and finally demonstrate that the system can be made boundary stable. © 2013 World Scientific Publishing Company.

Behrens A.,Cancer Research UK Research Institute | Behrens A.,Kings College London | Van Deursen J.M.,Rochester College | Rudolph K.L.,Leibniz Institute for Age Research | And 3 more authors.
Nature Cell Biology | Year: 2014

Impairment of stem cell function contributes to the progressive deterioration of tissue maintenance and repair with ageing. Evidence is mounting that age-dependent accumulation of DNA damage in both stem cells and cells that comprise the stem cell microenvironment are partly responsible for stem cell dysfunction with ageing. Here, we review the impact of the various types of DNA damage that accumulate with ageing on stem cell functionality, as well as the development of cancer. We discuss DNA-damage-induced cell intrinsic and extrinsic alterations that influence these processes, and review recent advances in understanding systemic adjustments to DNA damage and how they affect stem cells. © 2014 Macmillan Publishers Limited. All rights reserved.

Althofer I.,Friedrich - Schiller University of Jena
ICGA Journal | Year: 2011

In a game, pure Monte Carlo search with parameter T means that for each feasible move T random games are generated. The move with the best average score is played. We call a game "Monte Carlo perfect" when this straightforward procedure converges to perfect play for each position, when T goes to infinity. Most popular games like Go, Hex, and Amazons are NOT Monte Carlo perfect. In this paper, two-player zero-sum games are investigated where the turn-order is random: always a fair coin flip decides which player acts on the next move. A whole class of such random-turn games is proven to be Monte Carlo perfect. The result and generalisations are discussed, with example games ranging from very abstract to very concrete.

Eckoldt-Wolke F.,Friedrich - Schiller University of Jena
Endocrine Development | Year: 2014

This chapter refers only to female patients with congenital adrenal hyperplasia (CAH). CAH represents the largest subgroup of individuals with 46,XX disorders of sex development. The stimulation of the androgen production leads to a prenatal virilization among these girls. The phenotype is influenced by the severity of the enzyme defect, leading to a virilization of the external genitalia in varying degrees. On the other hand, the affected girls are clearly anatomically female with regularly developed female internal genitalia. Female puberty and potential female fertility are therefore to be expected. The operation to feminize the genitalia includes the separation of the sinus urogenitalis, the creation of a functionally wide enough vagina, the remodeling of the labioscrotal folds to create larger labia, and, if necessary, a reduction clitoroplasty. Considering the lack of scientific evidence, it is not possible to make definitive statements regarding the timing of surgery for girls with CAH. There are no studies that prove whether one- or two-stage surgery provides more or clearer advantages. © 2014 S. Karger AG, Basel.

Sauerbrei A.,Friedrich - Schiller University of Jena
World Journal of Gastroenterology | Year: 2014

The hepatitis B virus (HBV) is considered to be a major public health problem worldwide, and a significant number of reports on nosocomial outbreaks of HBV infections have been reported. Prevention of indirect HBV transmission by contaminated objects is only possible through the use of infection-control principles, including the use of chemical biocides, which are proven to render the virus non-infectious. The virucidal activity of biocides against HBV cannot be predicted; therefore, validation of the virucidal action of disinfectants against HBV is essential. However, feasible HBV infectivity assays have not yet been established. Thus, surrogate models have been proposed for testing the efficacy of biocides against HBV. Most of these assays do not correlate with HBV infectivity. Currently, the most promising and feasible assay is the use of the taxonomically related duck hepatitis B virus (DHBV), which belongs to the same Hepadnaviridae virus family. This paper reviews the application of DHBV, which can be propagated in vitro in primary duck embryonic hepatocytes, for the testing of biocides and describes why this model can be used as reliable method to evaluate disinfectants for efficacy against HBV. The susceptibility levels of important biocides, which are often used as ingredients for commercially available disinfectants, are also described. © 2014 Baishideng Publishing Group Co., Limited. All rights reserved.

Hoye T.T.,University of Aarhus | Hammel J.U.,Friedrich - Schiller University of Jena
Climate Research | Year: 2010

Climate change is advancing the onset of the growing season, and this is happening at a particularly fast rate in the Arctic. Although this has recently been shown to affect the sexual size dimorphism (SSD) of a wolf spider species through time, it remains to be shown whether spatial variation in the physical environment is similarly affecting SSD. We studied altitudinal variation in adult body size of male and female wolf spiders on Disko Island, West Greenland. Two species exhibited female-biased SSD (measured by carapace width) at sea level but not at higher altitudes. Males and females of a third species were of equal size at both altitudes, and the 2 remaining species found on Disko Island were only present at 1 low altitude site each. Altitudinal variation in SSD is probably a result of sex differences in body size response to shorter growing seasons with altitude. Our results suggest that climate change may result in increased SSD. Constraints on body size may increase with altitude, and expanding growing seasons due to climate change may predominantly affect SSD at higher altitudes. Such intra-specific effects of climate may be widespread and suggest that further research in this topic is needed. © Inter-Research 2010.

Jun J.E.,University of California at San Francisco | Rubio I.,Friedrich - Schiller University of Jena | Roose J.P.,University of California at San Francisco
Frontiers in Immunology | Year: 2013

The Ras-MAPK signaling pathway is highly conserved throughout evolution and is activated downstream of a wide range of receptor stimuli. Ras guanine nucleotide exchange factors (RasGEFs) catalyze GTP loading of Ras and play a pivotal role in regulating receptor-ligand induced Ras activity. In T cells, three families of functionally important RasGEFs are expressed: RasGRF, RasGRP, and Son of Sevenless (SOS)-family GEFs. Early on it was recognized that Ras activation is critical for T cell development and that the RasGEFs play an important role herein. More recent work has revealed that nuances in Ras activation appear to significantly impact T cell development and selection. These nuances include distinct biochemical patterns of analog versus digital Ras activation, differences in cellular localization of Ras activation, and intricate interplays between the RasGEFs during distinct T cell developmental stages as revealed by various new mouse models. In many instances, the exact nature of these nuances in Ras activation or how these may result from fine-tuning of the RasGEFs is not understood. One large group of biomolecules critically involved in the control of RasGEFs functions are lipid second messengers. Multiple, yet distinct lipid products are generated following T cell receptor (TCR) stimulation and bind to different domains in the RasGRP and SOS RasGEFs to facilitate the activation of the membrane-anchored Ras GTPases. In this review we highlight how different lipid-based elements are generated by various enzymes downstream of the TCR and other receptors and how these dynamic and interrelated lipid products may fine-tune Ras activation by RasGEFs in developing T cells. © 2013 Jun, Rubio and Roose.

Zipfel P.F.,Leibniz Institute for Natural Product Research and Infection Biology | Zipfel P.F.,Friedrich - Schiller University of Jena | Hallstrom T.,Leibniz Institute for Natural Product Research and Infection Biology | Riesbeck K.,Lund University
Molecular Immunology | Year: 2013

Complement is a central homeotic system of mammals and represents the first defense line of innate immunity. The human complement system is aimed to maintain homeostasis by recognizing and removing damaged or modified self material, as well as infectious foreign microbes. However, pathogenic microbes also control and escape the host complement and immune attack. The increasing resistance of microbial pathogens to either antibiotics or antifungal drugs is a major health problem and is of global interest. Therefore the topic how pathogenic microbes escape human complement and immune control is of high and of central interest. Identifying and defining the action of proteins involved in this intense immune interaction and understanding how these proteins interact is of relevance to design new control strategies. In this review we summarize the complement system of the human host and how this cascade drives effector functions. In addition, we summarize how diverse pathogenic microbes control, modulate and block the complement response of their host. The characterization of pathogen derived virulence factors and complement escape proteins reveals patterns of multiplicity, diversity and redundancy among pathogen encoded proteins. Sequence variability of immune and also complement escape proteins is largely driven by antigenic diversity and adaptive immunity. However common complement escape principles are, emerging in terms of conserved binding repertoire for host regulators and evasion among the large variety of infectious microbes. These conserved and common escape features are relevant and they provide challenging options for new therapeutic approaches. © 2013 Elsevier Ltd.

Lautenschlager C.,University Hospital Jena | Schmidt C.,University Hospital Jena | Fischer D.,Friedrich - Schiller University of Jena | Stallmach A.,University Hospital Jena
Advanced Drug Delivery Reviews | Year: 2014

Inflammatory bowel disease (IBD) is a frequently occurring disease in young people, which is characterized by a chronic inflammation of the gastrointestinal tract. The therapy of IBD is dominated by the administration of anti-inflammatory and immunosuppressive drugs, which suppress the intestinal inflammatory burden and improve the disease-related symptoms. Established treatment strategies are characterized by a limited therapeutical efficacy and the occurrence of adverse drug reactions. Thus, the development of novel disease-targeted drug delivery strategies is intended for a more effective therapy and demonstrates the potential to address unmet medical needs. This review gives an overview about the established as well as future-oriented drug targeting strategies, including intestine targeting by conventional drug delivery systems (DDS), disease targeted drug delivery by synthetic DDS and disease targeted drug delivery by biological DDS. Furthermore, this review analyses the targeting mechanisms of the respective DDS and discusses the possible field of utilization in IBD. © 2014 Elsevier B.V.

Witschas B.,German Aerospace Center | Witschas B.,Friedrich - Schiller University of Jena
Applied Optics | Year: 2011

Atmospheric lidar techniques for the measurement of wind, temperature, and optical properties of aerosols as well as nonintrusive measurement techniques for temperature, density, and bulk velocity in gas flows rely on the exact knowledge of the spectral line shape of the scattered laser light on molecules. A mathematically complex, numerical model (Tenti S6 model) is currently the best model for describing these spectra. In this paper an easy processable, alternative analytical model for describing spontaneous Rayleigh-Brillouin spectra in air at atmospheric conditions is introduced. The deviations between the analytical and Tenti S6 models are shown to be smaller than 0.85%. © 2011 Optical Society of America.

Steinhoff J.,Friedrich - Schiller University of Jena
Annalen der Physik (Leipzig) | Year: 2011

The present article aims at an extension of the canonical formalism of Arnowitt, Deser, and Misner from self-gravitating point-masses to objects with spin. This would allow interesting applications, e.g., within the post-Newtonian (PN) approximation. The extension succeeded via an action approach to linear order in the single spins of the objects without restriction to any further approximation. An order-by-order construction within the PN approximation is possible and performed to the formal 3.5PN order as a verification. In principle both approaches are applicable to higher orders in spin. The PN next-to-leading order spin(1)- spin(1) level was tackled, modeling the spin-induced quadrupole deformation by a single parameter. All spin-dependent Hamiltonians for rapidly rotating bodies up to and including 3PN are calculated. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cox S.,Kings College London | Rosten E.,University of Cambridge | Rosten E.,Computer Vision Consulting Ltd. | Monypenny J.,Kings College London | And 7 more authors.
Nature Methods | Year: 2012

We describe a localization microscopy analysis method that is able to extract results in live cells using standard fluorescent proteins and xenon arc lamp illumination. Our Bayesian analysis of the blinking and bleaching (3B analysis) method models the entire dataset simultaneously as being generated by a number of fluorophores that may or may not be emitting light at any given time. The resulting technique allows many overlapping fluorophores in each frame and unifies the analysis of the localization from blinking and bleaching events. By modeling the entire dataset, we were able to use each reappearance of a fluorophore to improve the localization accuracy. The high performance of this technique allowed us to reveal the nanoscale dynamics of podosome formation and dissociation throughout an entire cell with a resolution of 50 nm on a 4-s timescale. © 2012 Nature America, Inc. All rights reserved.

Jaranowski P.,University of Bialystok | Schafer G.,Friedrich - Schiller University of Jena
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

The article delivers the only still unknown coefficient in the 4th post-Newtonian energy expression for binary point masses on circular orbits as a function of orbital angular frequency. Apart from a single coefficient, which is known solely numerically, all the coefficients are given as exact numbers. The shown Hamiltonian is presented in the center-of-mass frame and out of its 57 coefficients, 51 are given fully explicitly. Those coefficients are six coefficients more than previously achieved [P. Jaranowski and G. Schäfer, Phys. Rev. D 86, 061503(R) (2012)PRVDAQ1550-7998]. The local divergences in the point-mass model are uniquely controlled by the method of dimensional regularization. As an application, the last stable circular orbit is determined as a function of the symmetric-mass-ratio parameter. © 2013 American Physical Society.

Bambi C.,Fudan University | Lukes-Gerakopoulos G.,Friedrich - Schiller University of Jena
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

Black hole candidates in X-ray binary systems and at the centers of galaxies are expected to be the Kerr black holes of general relativity, but the actual nature of these objects has yet to be verified. In this paper, we consider the possibility that they are exotic compact objects and we describe their exterior gravitational field with a subclass of the Manko-Novikov metrics, which are exact solutions of the vacuum Einstein's equations and can describe the spacetime geometry around bodies with arbitrary mass-multipole moments. We point out that around a Manko-Novikov object there may exist many disconnected nonplunging regions at small radii, with no counterpart in the Kerr background, and that their existence may be tested. For instance, in the presence of an accretion disk, they may be filled by the accreting gas, forming a ring structure that might remind the one of the rings of Saturn. We suggest that the existence of these regions may have a clear observational signature in the waveform of the gravitational radiation emitted by an extreme-mass-ratio inspiral: in the last stage of the inspiral, the waveform would be the combination of "regular chirps," produced when the small object orbits in one of the nonplunging regions, and "bursts," which are released when the small object jumps from a nonplunging region to another one at smaller radii. Our conclusions are supported by some numerical calculations of trajectories in the geodesic approximation, in which a particle plunges from the innermost stable circular orbit and then seems to get trapped in the potential well at smaller radii. © 2013 American Physical Society.

Geissler A.,TU Darmstadt | Biesalski M.,TU Darmstadt | Heinze T.,Friedrich - Schiller University of Jena | Zhang K.,TU Darmstadt
Journal of Materials Chemistry A | Year: 2014

Nanoparticles (NPs) from derivatives of native polysaccharides have not been as intensively studied yet as those from synthetic polymers. In this report, NPs in aqueous suspensions were fabricated using cellulose stearoyl esters (CSEs) with different molecular weights via nanoprecipitation using dropping and dialysis techniques. The average diameters of NPs depended strongly on the concentrations of CSE solutions, molecular weights of CSE and also the nanoprecipitation technique. Both nanoprecipitation techniques are based on different mechanisms and NPs from dialysis are generally larger than NPs from dropping. The mechanism for dropping nanoprecipitation was further analyzed based on the properties of NPs which contain crystallized stearoyl groups in CSE chains. The average diameters of freshly-prepared CSE nanoparticles decreased with rising temperature, which is accompanied by the release of THF from the interior of NPs. The intensity of the size reduction of up to 35% depended on the one hand on the concentration of CSE solutions, and on the other hand on the molecular weights of CSEs. Finally, it was shown that these NPs can be used for the fabrication of temperature-responsive superhydrophobic surfaces. © 2014 The Royal Society of Chemistry.

Wakai F.,Tokyo Institute of Technology | Guillon O.,Friedrich - Schiller University of Jena
Acta Materialia | Year: 2014

The sintering stress is a driving force for morphological evolution of pores in sintering, and can be determined from knowledge of the microstructure. The sintering stress of non-equilibrium, non-uniform and non-isotropic porous glass films cast and sintered on rigid substrates was computed from synchrotron X-ray microtomography data. This method was able to show how the inhomogeneous distribution of local density at the particle scale led to a difference in local sintering stress. The anisotropic microstructure in the film was correlated to the deviatoric components of the sintering stress, which were defined by surface energy tensor. The topological evolution of pore structure was characterized by genus and Euler characteristic. © 2013 Elsevier Inc. All rights reserved.

Kotzing T.,Friedrich - Schiller University of Jena
Algorithmica | Year: 2015

Recent advances in drift analysis have given us better and better tools for understanding random processes, including the run time of randomized search heuristics. In the setting of multiplicative drift we do not only have excellent bounds on the expected run time, but also more general results showing the strong concentration of the run time. In this paper we investigate the setting of additive drift under the assumption of strong concentration of the “step size” of the process. Under sufficiently strong drift towards the goal we show a strong concentration of the hitting time. In contrast to this, we show that in the presence of small drift a Gambler’s-Ruin-like behavior of the process overrides the influence of the drift, leading to a maximal movement of about (Formula presented.) steps within t iterations. Finally, in the presence of sufficiently strong negative drift the hitting time is superpolynomial with high probability; this corresponds to the well-known Negative Drift Theorem. © 2015 Springer Science+Business Media New York

Van Mierlo W.L.,University of Bayreuth | Van Mierlo W.L.,University of Ulm | Langenhorst F.,University of Bayreuth | Langenhorst F.,Friedrich - Schiller University of Jena | And 2 more authors.
Nature Geoscience | Year: 2013

Oceanic lithosphere sinks into Earth's mantle at subduction zones. However, seismic tomography shows that the sinking slabs of lithosphere often stagnate in the lower part of the mantle transition zone, at depths less than 660 km, where rocks undergo pressure-induced phase transitions and become denser. Greater pressures are required to induce phase transitions in cold slabs compared with the hotter ambient mantle at the 660 km discontinuity, and so, at the boundary between the transition zone and the lower mantle, the slabs are buoyant. The slabs may also contain low-density minerals that could contribute to their buoyancy. Here we use laboratory experiments to analyse the rate of dissolution of the common slab mineral pyroxene into garnet, at pressures and temperatures representative of the lower part of the mantle transition zone. We find that the majorite component in garnet - a product of the transition from pyroxene into garnet - is one of the slowest-diffusing components in Earth's mantle. At the relatively low temperatures of the slab, this slow diffusion inhibits the dissolution of pyroxene into garnet, so that the slab remains buoyant relative to the ambient mantle and stagnates. However, at the base of the mantle transition zone, pyroxene undergoes another phase transformation to the mineral akimotoite, which causes a sudden increase in slab density. We conclude that the slab is likely to penetrate into the lower mantle eventually.

Johnson-Mcdaniel N.K.,Friedrich - Schiller University of Jena
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

We show that there is a direct relation between upper limits on (or potential future measurements of) the m=2 quadrupole moments of slowly rotating neutron stars and the l=m=2 deformation of the star's surface, in full general relativity, to first order in the perturbation. This relation only depends on the star's structure through its mass and radius. All one has to assume about the star's constituents is that the stress-energy tensor at its surface is that of a perfect fluid, which will be true with good accuracy in almost all the situations of interest, and that the magnetic field configuration there is force free, which is likely to be a good approximation. We then apply this relation to the stars which have direct LIGO/Virgo bounds on their m=2 quadrupole moment, below the spin-down limit, and compare with the expected surface deformations due to rotation. In particular, we find that LIGO observations have constrained the Crab pulsar's l=m=2 surface deformation to be smaller than its l=2, m=0 deformation due to rotation, for all the causal equations of state we consider, a statement that could not have been made just using the upper bounds on the l=m=2 deformation from electromagnetic observations. © 2013 American Physical Society.

Groschel A.H.,University of Bayreuth | Schacher F.H.,Friedrich - Schiller University of Jena | Schmalz H.,University of Bayreuth | Borisov O.V.,French National Center for Scientific Research | And 4 more authors.
Nature Communications | Year: 2012

Hierarchical self-assembly offers elegant and energy-efficient bottom-up strategies for the structuring of complex materials. For block copolymers, the last decade witnessed great progress in diversifying the structural complexity of solution-based assemblies into multicompartment micelles. However, a general understanding of what governs multicompartment micelle morphologies and polydispersity, and how to manipulate their hierarchical superstructures using straightforward concepts and readily accessible polymers remains unreached. Here we demonstrate how to create homogeneous multicompartment micelles with unprecedented structural control via the intermediate pre-assembly of subunits. This directed self-assembly leads to a step-wise reduction of the degree of conformational freedom and dynamics and avoids undesirable kinetic obstacles during the structure build-up. It yields a general concept for homogeneous populations of well-defined multicompartment micelles with precisely tunable patchiness, while using simple linear ABC triblock terpolymers. We further demonstrate control over the hierarchical step-growth polymerization of multicompartment micelles into micron-scale segmented supracolloidal polymers as an example of programmable mesoscale colloidal hierarchies via well-defined patchy nanoobjects. © 2012 Macmillan Publishers Limited. All rights reserved.

Damour T.,Institute des Hautes etudes Scientifiques | Nagar A.,Institute des Hautes etudes Scientifiques | Bernuzzi S.,Friedrich - Schiller University of Jena
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

We improve the effective-one-body (EOB) description of nonspinning coalescing black-hole binaries by incorporating several recent analytical advances, notably: (i) logarithmic contributions to the conservative dynamics; (ii) resummed horizon-absorption contribution to the orbital angular momentum loss; and (iii) a specific radial component of the radiation-reaction force implied by consistency with the azimuthal one. We then complete this analytically improved EOB model by comparing it to accurate numerical-relativity (NR) simulations performed by the Caltech-Cornell-CITA group for mass ratios q=(1,2,3,4,6). In particular, the comparison to NR data allows us to determine with high accuracy (∼104) the value of the main EOB radial potential: A(u;ν), where u=GM/(Rc2) is the interbody gravitational potential and ν=q/(q+1)2 is the symmetric mass ratio. We introduce a new technique for extracting from NR data an intrinsic measure of the phase evolution [Qω(ω) diagnostics]. Aligning the NR-completed EOB quadrupolar waveform and the NR one at low frequencies, we find that they keep agreeing (in phase and amplitude) within the NR uncertainties throughout the evolution for all mass ratios considered. We also find good agreement for several subdominant multipoles without having to introduce and tune any extra parameters. © 2013 American Physical Society.

Van Schrojenstein Lantman E.M.,University Utrecht | Deckert-Gaudig T.,Institute of Photonic Technology | Mank A.J.G.,University Utrecht | Mank A.J.G.,HIGH-TECH | And 3 more authors.
Nature Nanotechnology | Year: 2012

Heterogeneous catalysts play a pivotal role in the chemical industry, but acquiring molecular insights into functioning catalysts remains a significant challenge. Recent advances in micro-spectroscopic approaches have allowed spatiotemporal information to be obtained on the dynamics of single active sites and the diffusion of single molecules. However, these methods lack nanometre-scale spatial resolution and/or require the use of fluorescent labels. Here, we show that time-resolved tip-enhanced Raman spectroscopy can monitor photocatalytic reactions at the nanoscale. We use a silver-coated atomic force microscope tip to both enhance the Raman signal and to act as the catalyst. The tip is placed in contact with a self-assembled monolayer of p-nitrothiophenol molecules adsorbed on gold nanoplates. A photocatalytic reduction process is induced at the apex of the tip with green laser light, while red laser light is used to monitor the transformation process during the reaction. This dual-wavelength approach can also be used to observe other molecular effects such as monolayer diffusion. © 2012 Macmillan Publishers Limited. All rights reserved.

Pohl H.,Friedrich - Schiller University of Jena
Microscopy Research and Technique | Year: 2010

The specimen holder for scanning electron microscopy described herein allows a single specimen to be examined in any possible view and significantly improves object illumination. The specimen is glued to a fine pin and flexibly mounted on a double-sided adhesive conductive pad on a rotatable pivot. A milled pot placed beneath the specimen acts as an electron trap. This provides a homogeneous black image background by minimizing noisy signals from the specimen's surroundings. Microsc. Res. Tech. 73:1073-1076, 2010. © 2010 Wiley-Liss, Inc.

Kupfer S.,Friedrich - Schiller University of Jena | Guthmuller J.,Technical University of Gdansk | Gonzalez L.,University of Vienna
Journal of Chemical Theory and Computation | Year: 2013

The excitation energies and gradients in the ground and the first excited state of a novel donor-(π-bridge)-acceptor 4-methoxy-1,3-thiazole-based chromophore were investigated by means of MS-RASPT2/RASSCF and TDDFT in solution. Within both methods, the excitation energies strongly depend on the employed equilibrium structures, whose differences can be rationalized in terms of bond length alternation indexes. It is shown that functionals with an increased amount of exact exchange provide the best estimation of the ground and excited state properties. While B3LYP fails to predict the excitation energies due to its intrinsic problems in describing charge transfer (CT) states, the long-range corrected CAM-B3LYP and M06-2X functionals deliver good agreement with the experimental UV/vis absorption spectrum. The calculation of resonance Raman intensity patterns is used to discern which ground and excited state gradients are best. The results clearly evidence that both CAM-B3LYP and RASSCF excited state gradients and energies in combination with CAM-B3LYP ground state gradients are appropriate to describe the CT state of this push-pull chromophore. © 2012 American Chemical Society.

Karbstein F.,Friedrich - Schiller University of Jena | Karbstein F.,Helmholtz Center for Heavy Ion Research
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

We revisit the photon polarization tensor in a homogeneous external magnetic or electric field. The starting point of our considerations is the momentum space representation of the one-loop photon polarization tensor in the presence of a homogeneous electromagnetic field, known in terms of a double parameter integral. Our focus is on explicit analytical insights for both on- and off-the-light-cone dynamics in a wide range of well-specified physical parameter regimes, ranging from the perturbative to the manifestly nonperturbative strong field regime. The basic ideas underlying well-established approximations to the photon polarization tensor are carefully examined and critically reviewed. In particular, we systematically keep track of all contributions, both the ones to be neglected and those to be taken into account explicitly, to all orders. This allows us to study their ranges of applicability in a much more systematic and rigorous way. We point out the limitations of such approximations and manage to go beyond at several instances. © 2013 American Physical Society.

Brugmann B.,Friedrich - Schiller University of Jena
Journal of Computational Physics | Year: 2013

We construct a pseudospectral method for the solution of time-dependent, non-linear partial differential equations on a three-dimensional spherical shell. The problem we address is the treatment of tensor fields on the sphere. As a test case we consider the evolution of a single black hole in numerical general relativity. A natural strategy would be the expansion in tensor spherical harmonics in spherical coordinates. Instead, we consider the simpler and potentially more efficient possibility of a double Fourier expansion on the sphere for tensors in Cartesian coordinates. As usual for the double Fourier method, we employ a filter to address time-step limitations and certain stability issues. We find that a tensor filter based on spin-weighted spherical harmonics is successful, while two simplified, non-spin-weighted filters do not lead to stable evolutions. The derivatives and the filter are implemented by matrix multiplication for efficiency. A key technical point is the construction of a matrix multiplication method for the spin-weighted spherical harmonic filter. As example for the efficient parallelization of the double Fourier, spin-weighted filter method we discuss an implementation on a GPU, which achieves a speed-up of up to a factor of 20 compared to a single core CPU implementation. © 2012 Elsevier Inc.

Brantl S.,Friedrich - Schiller University of Jena
Microbiology Spectrum | Year: 2014

Plasmids are selfish genetic elements that normally constitute a burden for the bacterial host cell. This burden is expected to favor plasmid loss. Therefore, plasmids have evolved mechanisms to control their replication and ensure their stable maintenance. Replication control can be either mediated by iterons or by antisense RNAs. Antisense RNAs work through a negative control circuit. They are constitutively synthesized and metabolically unstable. They act both as a measuring device and a regulator, and regulation occurs by inhibition. Increased plasmid copy numbers lead to increasing antisense-RNA concentrations, which, in turn, result in the inhibition of a function essential for replication. On the other hand, decreased plasmid copy numbers entail decreasing concentrations of the inhibiting antisense RNA, thereby increasing the replication frequency. Inhibition is achieved by a variety of mechanisms, which are discussed in detail. The most trivial case is the inhibition of translation of an essential replication initiator protein (Rep) by blockage of the rep-ribosome binding site. Alternatively, ribosome binding to a leader peptide mRNA whose translation is required for efficient Rep translation can be prevented by antisense-RNA binding. In 2004, translational attenuation was discovered. Antisense-RNA-mediated transcriptional attenuation is another mechanism that has, so far, only been detected in plasmids of Gram-positive bacteria. ColE1, a plasmid that does not need a plasmid-encoded replication initiator protein, uses the inhibition of primer formation. In other cases, antisense RNAs inhibit the formation of an activator pseudoknot that is required for efficient Rep translation. © 2014 American Society for Microbiology. All rights reserved.

Hofler M.,Friedrich - Schiller University of Jena
International Journal of Disaster Risk Science | Year: 2014

This article discusses three questions: What opportunities exist to enhance psychological resilience in adults? Why should psychological resilience promotion be considered an important disaster risk reduction strategy? What contribution can adult education make to such a strategy? Psychological resilience is presented as relational and somewhat malleable, even in adulthood. Although psychological resilience building is often overlooked in social-level disaster risk reduction efforts, it is a key strategy for social resilience building. Questions regarding the extent to which mental resilience can be improved and the techniques with which to do so may be answered by research in the field of adult education. Basic learning and teaching research fundamentals are suggested to create psychological resilience-building strategies in adults. © 2014, The Author(s).

Nyakatura J.A.,Friedrich - Schiller University of Jena | Heymann E.W.,Abteilung fur Verhaltensokologie und Soziobiologie
Journal of Human Evolution | Year: 2010

The adoption of a specific gait sequence pattern during symmetrical locomotion has been proposed to have been a key advantage for the exploitation of the fine branch niche in early primates. Diverse aspects of primate locomotion have been extensively studied in technically equipped laboratory settings, but evolutionary conclusions derived from these investigations have rarely been verified in wild primates. Bridging the gap from the lab to the field, we conducted an actual performance determination of symmetrical gaits in two free-ranging tamarin species (Saguinus mystax and Saguinus fuscicollis) of Amazonian Peru by analyzing high-speed video recordings of naturally occurring locomotor bouts. Tamarins arguably represent viable models for aspects of early primate locomotion. We tested three specific hypotheses derived from laboratory studies to test for the influence of support size and orientation and to gain further insight into the functional significance of primate gait sequence patterns: (1) The tamarins utilize symmetrical gaits at a higher rate on small supports than on larger ones. (2) During symmetrical locomotion on small supports, diagonal sequences are utilized at a higher rate than on larger supports. (3) On inclines, diagonal sequences are predominantly used and on declines, lateral sequences are predominantly used. Our results corroborated hypotheses 1 and 3. We found no clear support for hypothesis 2. In conclusion, our results add to the notion that primate gait plasticity, rather than uniform adoption of diagonal sequence gaits, enabled early primates to accommodate different support types and effectively exploit the small branch niche. © 2009 Elsevier Ltd. All rights reserved.

Hubner C.A.,Friedrich - Schiller University of Jena
EMBO Reports | Year: 2014

In the mature brain, the neurotransmitter GABA can cause a postsynaptic hyperpolarization via activation of chloride permeant GABAA receptor channels. This hyperpolarizing response critically depends on chloride extrusion via the KCl-cotransporter KCC2 [1]. Its knockdown in mice impairs synaptic inhibition by changing the electrochemical potential for chloride and thus increases neuronal excitability. Two independent groups provide first evidence now, published in EMBO reports, that rare variants of KCC2 confer an increased risk of epilepsy in men [4,5]. © 2014 The Authors.

Brantl S.,Friedrich - Schiller University of Jena
Plasmid | Year: 2015

Over the past decade, a wealth of small noncoding RNAs (sRNAs) have been discovered in the genomes of almost all bacterial species, where they constitute the most abundant class of posttranscriptional regulators. These sRNAs are key-players in prokaryotic metabolism, stress response and virulence. However, the first bona-fide antisense RNAs had been found already in 1981 in plasmids, where they regulate replication or maintenance. Antisense RNAs involved in plasmid replication control - meanwhile investigated in depth for almost 35years - employ a variety of mechanisms of action: They regulate primer maturation, inhibit translation of essential replication initiator proteins (Rep proteins) as well as leader peptides or the formation of activator pseudoknots required for efficient rep translation. Alternatively they attenuate transcription or translation of rep mRNAs. Some antisense RNAs collaborate with transcriptional repressors to ensure proper copy-number control. Here, I summarize our knowledge on replication control of the broad-host range plasmid pIP501 that was originally isolated from Streptococcus agalactiae. Plasmid pIP501 uses two copy number-control elements, RNAIII, a cis-encoded antisense RNA, and transcriptional repressor CopR. RNA III mediates transcription attenuation, a rather widespread concept that found its culmination in the recent discovery of riboswitches. A peculiarity of pIP501 is the unusual stability of RNA III, which requires a second function of CopR: CopR does not only repress transcription from the essential repR promoter, but also prevents convergent transcription between rep mRNA and RNAIII, thereby indirectly increasing the amount of RNAIII. The concerted action of these two control elements is necessary to prevent plasmid loss at dangerously low copy numbers. © 2014 Elsevier Inc.

Rumpel C.,IRD Montpellier | Eusterhues K.,Friedrich - Schiller University of Jena | Kogel-Knabner I.,Wissenschaftszentrum Weihenstephan
Soil Biology and Biochemistry | Year: 2010

We investigated the polysaccharide composition of bulk and mineral-bound (density fractions >2 g cm-3) organic matter in topsoil and subsoil horizons of a Podzol and a Cambisol. Total sugar contents were generally higher in the Cambisol than in the Podzol. For most horizons of both soils, the sugars were enriched in the mineral-bound organic matter fraction. This fraction showed a monosaccharide distribution typical for microbial sugars, whereas in bulk soil horizons higher contributions of plant-derived sugars were observed. A strong relationship with the 14C activity of the dense fraction suggests that microbial-derived polysaccharides are most likely stabilised preferentially by mineral interactions compared to plant-derived polysaccharides. © 2009 Elsevier Ltd. All rights reserved.

Kahya E.O.,Friedrich - Schiller University of Jena
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2011

We present an extension of a previously suggested test of all modified theories of gravity that would reproduce MOND at low accelerations. In a class of models, called "dark matter emulators", gravitational waves and other particles couple to different metrics. This leads to a detectable time lag between their detection at Earth from the same source. We calculate this time lag numerically for any event that occurs in our galaxy up to 400 kpc, and present a graph of this possible time lag. This suggests that, gravitational wave observers might have to consider the possibility of extending their analysis to non-coincident gravitational and electromagnetic signals, and the graph that we present might be a useful guideline for this effort. © 2011 Elsevier B.V.

Seidel P.,Friedrich - Schiller University of Jena
Superconductor Science and Technology | Year: 2011

Just after the discovery of the iron based superconductors (iron pnictides) important differences from the conventional as well as to the high temperature superconducting cuprates were found. The complex band structure (multiple energy gaps, the unconventional symmetry of the superconducting order parameter and the unknown nature of the Cooper pair coupling mechanism) results in interesting new properties of these materials. This review summarizes the status of theoretical and experimental results on Josephson effects in the iron pnictides connected to these unusual properties. On one hand the investigation of Josephson effects can be a helpful tool to determine these properties and to test different theoretical models, but on the other hand these properties may lead to new kinds of Josephson junctions and future applications. © 2011 IOP Publishing Ltd.

Don A.,Johann Heinrich Von Thunen Institute | Schumacher J.,Friedrich - Schiller University of Jena | Freibauer A.,Johann Heinrich Von Thunen Institute
Global Change Biology | Year: 2011

Land-use changes are the second largest source of human-induced greenhouse gas emission, mainly due to deforestation in the tropics and subtropics. CO2 emissions result from biomass and soil organic carbon (SOC) losses and may be offset with afforestation programs. However, the effect of land-use changes on SOC is poorly quantified due to insufficient data quality (only SOC concentrations and no SOC stocks, shallow sampling depth) and representativeness. In a global meta-analysis, 385 studies on land-use change in the tropics were explored to estimate the SOC stock changes for all major land-use change types. The highest SOC losses were caused by conversion of primary forest into cropland (-25%) and perennial crops (-30%) but forest conversion into grassland also reduced SOC stocks by 12%. Secondary forests stored less SOC than primary forests (-9%) underlining the importance of primary forests for C stores. SOC losses are partly reversible if agricultural land is afforested (+29%) or under cropland fallow (+32%) and with cropland conversion into grassland (+26%). Data on soil bulk density are critical in order to estimate SOC stock changes because (i) the bulk density changes with land-use and needs to be accounted for when calculating SOC stocks and (ii) soil sample mass has to be corrected for bulk density changes in order to compare land-use types on the same basis of soil mass. Without soil mass correction, land-use change effects would have been underestimated by 28%. Land-use change impact on SOC was not restricted to the surface soil, but relative changes were equally high in the subsoil, stressing the importance of sufficiently deep sampling. © 2010 Blackwell Publishing Ltd.

Maas A.,Friedrich - Schiller University of Jena
Journal of High Energy Physics | Year: 2011

The technicolor scenario replaces the Higgs sector of the standard model with a strongly interacting sector. One candidate for a realization of such a sector is two-technicolor Yang-Mills theory coupled to two degenerate flavours of adjoint, massless techniquarks. Using lattice gauge theory the properties of the technigluons in this scenario are investigated as a function of the techniquark mass towards the massless limit. For that purpose the minimal Landau gauge two-point and three-point correlation functions are determined, including a detailed systematic error analysis. The results are, within the relatively large systematic uncertainties, compatible with a behavior very similar to QCD at finite techniquark mass. However, the limit of massless techniquarks exhibits features which could be compatible with a (quasi-)conformal behavior. © SISSA 2011.

Darensbourg M.Y.,Texas A&M University | Weigand W.,Friedrich - Schiller University of Jena
European Journal of Inorganic Chemistry | Year: 2011

The organometallic active sites in [NiFe]- and [FeFe]H2ases are sensitive to oxygen in varying degrees. The microorganisms that utilize these enzymes for their hydrogen metabolism, and the enzymes themselves, have evolved from a reducing to an oxidizing environment in ways to avoid competition with oxygen, primarily by burying the active site machinery deeply within the protein matrix. In the case of [Ni-Fe]H2ase, biological studies indicate that repair mechanisms exist for reversible O2-inhibition processes. This Microreview explores the possibility that S-oxygenation may represent reparable O-damaged enzyme active sites. Such S-oxygenation has precedent in chemical models for the terminal thiolate sulfur atoms of the nickel site in [NiFe]H2ase as well as the bridging thiolate sulfur in the [FeFe]H2ase active site. A discussion of the processes of O 2 damage leading to both reversible and irreversible enzyme inhibition, and reclamation of activity in the H2ases, as explored by various biochemical assays and spectroscopic methods, is also presented. © 2011 Wiley-VCH Verlag GmbH & Co. KGaA.

Plass W.,Friedrich - Schiller University of Jena
Coordination Chemistry Reviews | Year: 2011

Supramolecular interactions and hydrogen bonding play a fundamental role in determining both structure and function of vanadate in enzymatic systems and in particular for the active site of vanadium haloperoxidases. Vanadium complexes with N-salicylidene hydrazide ligands provide a versatile approach towards molecular model systems with hydrogen bonding interactions. The variation of the side chains within these hydrazone ligands provides the ability to introduce chirality in molecular model complexes by the utilization of appropriate carbohydrate fragments. Moreover, the synthetic potential and the transformation reactions found for dioxidovanadium(V) complexes with N-salicylidene hydrazide ligands are reminiscent of what is usually observed for carboxylates and can therefore be regarded as their inorganic counterpart. The anisotropy effect of the oxido groups in vanadium complexes is a valuable tool that allows for the configurational and conformational analysis of structures with corresponding chelate rings. Utilizing appropriate vanadium complexes it is possible to generate inclusion compounds with cyclodextrins. The dependence of solid state and solution structures on the ring size of the cyclodextrin is discussed. © 2011 Elsevier B.V.

Van de Schoot R.,University Utrecht | Van de Schoot R.,North West University South Africa | Kaplan D.,University of Wisconsin - Madison | Denissen J.,University of Tilburg | And 3 more authors.
Child Development | Year: 2014

Bayesian statistical methods are becoming ever more popular in applied and fundamental research. In this study a gentle introduction to Bayesian analysis is provided. It is shown under what circumstances it is attractive to use Bayesian estimation, and how to interpret properly the results. First, the ingredients underlying Bayesian methods are introduced using a simplified example. Thereafter, the advantages and pitfalls of the specification of prior knowledge are discussed. To illustrate Bayesian methods explained in this study, in a second example a series of studies that examine the theoretical framework of dynamic interactionism are considered. In the Discussion the advantages and disadvantages of using Bayesian statistics are reviewed, and guidelines on how to report on Bayesian statistics are provided. © 2013 Society for Research in Child Development, Inc.

Lecaplain C.,CNRS Complex Interprofessional Research in Aerothermochemistry | Baumgartl M.,Friedrich - Schiller University of Jena | Schreiber T.,Fraunhofer Institute for Applied Optics and Precision Engineering | Hideur A.,CNRS Complex Interprofessional Research in Aerothermochemistry
Optics Express | Year: 2011

We report on the generation of high-energy pulses in an all normal dispersion photonic-crystal fiber laser. Two mode-locking techniques with and without passive spectral filtering are studied both numerically and experimentally to address a roadmap for energy scaling. It is found that high-contrast passive modulation is a very promising modelocking technique for energy scaling in dissipative-soliton laser. Moreover, this technique does not need any additional spectral filtering than the limited gain bandwidth to stabilize high-energy ultrashort pulses. The presented laser generates 110 nJ chirped pulses at 57 MHz repetition rate for an average power of 6.2 W. The output pulses could be dechirped close to the transform-limited duration of 100 fs. © 2011 Optical Society of America.

Janssen R.,Uppsala University | Damen W.G.,Friedrich - Schiller University of Jena | Budd G.E.,Uppsala University
BMC Evolutionary Biology | Year: 2011

Background: A recent study on expression and function of the ortholog of the Drosophila collier (col) gene in various arthropods including insects, crustaceans and chelicerates suggested a de novo function of col in the development of the appendage-less intercalary segment of insects. However, this assumption was made on the background of the now widely-accepted Pancrustacea hypothesis that hexapods represent an in-group of the crustaceans. It was therefore assumed that the expression of col in myriapods would reflect the ancestral state like in crustaceans and chelicerates, i.e. absence from the premandibular/intercalary segment and hence no function in its formation. Results: We find that col in myriapods is expressed at early developmental stages in the same anterior domain in the head, the parasegment 0, as in insects. Comparable early expression of col is not present in the anterior head of an onychophoran that serves as an out-group species closely related to the arthropods. Conclusions: Our findings suggest either that i) the function of col in head development has been conserved between insects and myriapods, and that these two classes of arthropods may be closely related supporting the traditional Atelocerata (or Tracheata) hypothesis; or ii) alternatively col function could have been lost in early head development in crustaceans, or may indeed have evolved convergently in insects and myriapods. © 2011 Janssen et al.

Deckert-Gaudig T.,Institute of Photonic Technology | Deckert V.,Institute of Photonic Technology | Deckert V.,Friedrich - Schiller University of Jena
Current Opinion in Chemical Biology | Year: 2011

Tip-enhanced Raman scattering (TERS) enables the label-free investigation of biochemical interfaces with nanometer lateral resolution by combining the benefits of the intrinsic molecular specificity of Raman spectroscopy, the sensitivity because of signal enhancing capabilities of plasmonic nanoparticles, and the precision of scanning probe microscopy. The structural differentiation of constituents based on inherent molecular information is possible even down to a few nanometer spatial resolution and consequently, nucleobases, proteins, lipids, and carbohydrates can be identified and localized in a single measurement. This has been shown in the last few years for different biological samples ranging from single DNA strand investigations to cell membrane studies. © 2011 Elsevier Ltd.

Scriba G.K.E.,Friedrich - Schiller University of Jena
Journal of Pharmaceutical and Biomedical Analysis | Year: 2011

Capillary electromigration techniques are often considered ideal methods for the analysis of chiral compounds due to the high resolution power and flexibility of the technique. Therefore, especially capillary electrophoresis using a chiral selector in the background electrolyte, also termed electrokinetic chromatography, has found widespread acceptance in analytical enantioseparations of drug compounds in pharmaceuticals and biological media. Moreover, mechanistic studies on analyte complexation by the chiral selectors have continuously been conducted in an effort to rationalize enantioseparation phenomena. These studies combined capillary electrophoresis with spectroscopic techniques such as nuclear magnetic resonance and/or molecular modeling. The present review focuses on recent examples of mechanistic aspects of capillary electromigration enantioseparations and summarizes recent applications of chiral pharmaceutical and biomedical analysis published between January 2009 and August 2010. © 2010 Elsevier B.V.

Schilling N.,Friedrich - Schiller University of Jena
Frontiers in Zoology | Year: 2011

The axial musculoskeletal system represents the plesiomorphic locomotor engine of the vertebrate body, playing a central role in locomotion. In craniates, the evolution of the postcranial skeleton is characterized by two major transformations. First, the axial skeleton became increasingly functionally and morphologically regionalized. Second, the axial-based locomotion plesiomorphic for craniates became progressively appendage-based with the evolution of extremities in tetrapods. These changes, together with the transition to land, caused increased complexity in the planes in which axial movements occur and moments act on the body and were accompanied by profound changes in axial muscle function. To increase our understanding of the evolutionary transformations of the structure and function of the perivertebral musculature, this review integrates recent anatomical and physiological data (e.g., muscle fiber types, activation patterns) with gross-anatomical and kinematic findings for pivotal craniate taxa. This information is mapped onto a phylogenetic hypothesis to infer the putative character set of the last common ancestor of the respective taxa and to conjecture patterns of locomotor and muscular evolution. The increasing anatomical and functional complexity in the muscular arrangement during craniate evolution is associated with changes in fiber angulation and fiber-type distribution, i.e., increasing obliqueness in fiber orientation and segregation of fatigue-resistant fibers in deeper muscle regions. The loss of superficial fatigue-resistant fibers may be related to the profound gross anatomical reorganization of the axial musculature during the tetrapod evolution. The plesiomorphic function of the axial musculature -mobilization- is retained in all craniates. Along with the evolution of limbs and the subsequent transition to land, axial muscles additionally function to globally stabilize the trunk against inertial and extrinsic limb muscle forces as well as gravitational forces. Associated with the evolution of sagittal mobility and a parasagittal limb posture, axial muscles in mammals also stabilize the trunk against sagittal components of extrinsic limb muscle action as well as the inertia of the body's center of mass. Thus, the axial system is central to the static and dynamic control of the body posture in all craniates and, in gnathostomes, additionally provides the foundation for the mechanical work of the appendicular system. © 2011 Schilling; licensee BioMed Central Ltd.

Winter J.M.,Leibniz Institute for Natural Product Research and Infection Biology | Behnken S.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Friedrich - Schiller University of Jena
Current Opinion in Chemical Biology | Year: 2011

The massive surge in genome sequencing projects has opened our eyes to the overlooked biosynthetic potential and metabolic diversity of microorganisms. While traditional approaches have been successful at identifying many useful therapeutic agents from these organisms, new tactics are needed in order to exploit their true biosynthetic potential. Several genomics-inspired strategies have been successful in unveiling new metabolites that were overlooked under standard fermentation and detection conditions. In addition, genome sequences have given us valuable insight for genetically engineering biosynthesis gene clusters that remain silent or are poorly expressed in the absence of a specific trigger. As more genome sequences are becoming available, we are noticing the emergence of underexplored or neglected organisms as alternative resources for new therapeutic agents. © 2010 Elsevier Ltd.

Haenlein G.F.W.,University of Delaware | Anke M.,Friedrich - Schiller University of Jena
Small Ruminant Research | Year: 2011

The long term studies with dairy goats on the effects of deficient semisynthetic feeding rations in one of 16 elements as reported in the annual proceedings of the Workshops on Minerals and Trace Elements and the International Trace Element Symposia by the University of Jena, Germany, since 1975 until today were reviewed. The development of the complex semisynthetic ration system was particularly important as it enabled to produce significant deficiencies of single elements in long term replicated studies and their interactions with other elements. The studies focused mainly on determining deficiency levels for each of the 16 elements, identifying deficiency symptoms and reasons for them, and establishing evidence for essentiality of the elements according to 7 criteria. Large amounts of analytical data were accumulated showing the changes in organ and tissue contents of the elements under study at normal and deficient levels, and their relation to impaired reproductive efficiency, growth, milk production, health, and mortality of goats and their kids. Histological sections of organs also showed their ultrastructural changes due to the elemental deficiencies. Most element deficiencies caused reproductive failures, reduced growth and milk production, but high mortality, while the control goats thrived on their semisynthetic but sufficient ration, attesting to its completely correct biological value. The identification of the reliable " indicator" organs and tissues for the diagnosis and detection of deficiency status of the specific elements in goats is of particular value to veterinary medicine and animal nutrition. © 2010 Elsevier B.V.

Steyer R.,Friedrich - Schiller University of Jena | Mayer A.,Ghent University | Geiser C.,Utah State University | Cole D.A.,Vanderbilt University
Annual Review of Clinical Psychology | Year: 2015

We present a revision of latent state-trait (LST-R) theory with new definitions of states and traits. This theory applies whenever we study the consistency of behavior, its variability, and its change over time. States and traits are defined in terms of probability theory. This allows for a seamless transition from theory to statistical modeling of empirical data. LST-R theory not only gives insights into the nature of latent variables but it also takes into account four fundamental facts: Observations are fallible, they never happen in a situational vacuum, they are always made using a specific method of observations, and there is no person without a past. Although the first fact necessitates considering measurement error, the second fact requires allowances for situational fluctuations. The third fact implies that, in the first place, states and traits are method specific. Furthermore, compared to the previous version of LST theory (see, e.g., Steyer et al. 1992, 1999), our revision is based on the notion of a person-at-time-t. The new definitions in LST-R theory have far-reaching implications that not only concern the properties of states, traits, and the associated concepts of measurement errors and state residuals, but also are related to the analysis of states and traits in longitudinal observational and intervention studies. © 2015 by Annual Reviews. All rights reserved.

Konig E.,Friedrich - Schiller University of Jena | Bininda-Emonds O.R.P.,Carl von Ossietzky University
Peptides | Year: 2011

Amphibians are characterized in part by their highly specialized and glandular skin that enables key physiological functions such as cutaneous respiration and defense against a variety of micro- and macroscopic predators via toxic components (e.g., alkaloids and bufodienolids), biogenic amines, neuropeptides and antimicrobial peptides (AMPs). To date, DNA sequence information regarding AMP genes in anurans is restricted to only a few anuran families and largely to "higher frogs" (Neobatrachia). Here, we analyze the DNA information for the signal sequences of the AMP precursors in anuran amphibians available to the end of 2009 in an explicit phylogenetic framework to characterize the evolution of this large, diverse gene family. Comparison of cDNA sequences suggests that there are at least three different motifs within the signal peptide sequence of the AMP-precursor corresponding to the evolutionary lineages Neobatrachia, Bombinatoridae (Bombina spp.) and Pipidae (Xenopus laevis). The signal sequences are strongly conserved within each lineage (as previously noted for Neobatrachia), but highly divergent between them. Together with the lack of a linear relationship between the degree of sequence divergence and evolutionary time, we hypothesize that the anuran AMP system has evolved convergently on at least three occasions. However, additional sampling, especially among the largely poorly sampled non-neobatrachian lineages, is required to confirm this hypothesis and could reveal the existence of additional signal sequence motifs. © 2010 Elsevier Inc. All rights reserved.

Theiben G.,Friedrich - Schiller University of Jena
Journal of Experimental Botany | Year: 2014

For good reasons scientists usually do not report the personal circumstances of their work when publishing their results. This means, however, that the scientific facts being reported may not accurately reflect the personal importance of the respective work for the individual scientists. Pictures of pod corn (or Tunicate maize) have been on my mind for much of my life, through good and through bad times. © 2014 © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved.

Bergner G.,Friedrich - Schiller University of Jena
Journal of High Energy Physics | Year: 2010

In this work a lattice formulation of a supersymmetric theory is proposed and tested that preserves the complete supersymmetry on the lattice. The results of a onedimensional nonperturbative simulation show the realization of the full supersymmetry and the correct continuum limit of the theory. It is proven here that the violation of supersymmetry due to the absence of the Leibniz rule on the lattice can be amended only with a nonlocal derivative and nonlocal interaction term. The fermion doubling problem is also discussed, which leads to another important source of supersymmetry breaking on the lattice. This problem is also solved with a nonlocal realization. © SISSA 2010.

Titzmann P.F.,University of Zurich | Silbereisen R.K.,Friedrich - Schiller University of Jena | Mesch G.,Haifa University
Developmental Psychology | Year: 2014

On the basis of general theories of delinquency and the specific situation of immigrants, this longitudinal study investigated predictors of initial levels and rates of change in delinquency among 188 male ethnic German Diaspora immigrants from the former Soviet Union (FSU) in Germany, 237 male native German adolescents, and 182 male Jewish Diaspora adolescents from the FSU in Israel. The participants (15.2 years old) completed 3 annual assessments. Latent growth curve models showed that ethnic German adolescents reported higher initial levels of delinquency than native German adolescents and lower levels than the Russian Jewish adolescents. Groups did not differ in the rate of change, indicating a decrease in delinquency over time. Peer-oriented leisure related positively and parental knowledge negatively with levels and change rates in delinquency in all groups, but could not fully account for the ethnic differences in delinquency levels. School bonding was associated negatively with delinquency only among native German adolescents. Acculturation-related hassles were an additional predictor for higher levels and also associated with change rates in the immigrant groups. Thus, general theories of delinquency apply to immigrants, but may be complemented by adding acculturation-specific challenges. © 2013 American Psychological Association.

Little empirical research has been done to establish how time structures in the social domain affect the origination of psychological disorders and whether (and if so, how) such structures are reflected in the course(s) taken by those disorders. The author attempts to provide some initial answers by first recapitulating the essential features of his acceleration diagnosis and then relating these to sociologically interpretable forms of depression as the «classical» time-related disorder of the age.

Schmidt P.,Friedrich - Schiller University of Jena
GMS Zeitschrift fur Medizinische Ausbildung | Year: 2013

The development of digital media has been impressive in recent years which is also among the reason for their increasing use in academic teaching. This is especially true for teaching Anatomy and Histology in the first two years in medical and dental curricula. Modern digital technologies allow for efficient, affordable and easily accessible distribution of histological images in high quality. Microscopy depends almost exclusively on such images. Since 20 years numerous digital teaching systems have been developed for this purpose. Respective developments have changed the ways students acquire knowledge and prepare for exams. Teaching staff should adapt lectures, seminars and labs accordingly. As a first step, a collection of high resolution digital microscopic slides was made available for students at the Friedrich-Schiller-University in Jena. The aim of the present study was to evaluate the importance of conventional light microscopy and related technologies in current and future medical and dental education aswell. A survey was done among 172 medical and dental students at the Friedrich-Schiller-University Jena. 51% of students use now frequently new digital media for learning histology in contrast to 5% in the year 2000 [1]. Digital media including Internet, CD-based learning combined with social networks successfully compete with classical light microscopy. © 2013 Schmidt.

Hertweck C.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Friedrich - Schiller University of Jena
Trends in Biochemical Sciences | Year: 2015

Bacterial modular type I polyketide synthases (PKSs) represent giant megasynthases that produce a vast number of complex polyketides, many of which are pharmaceutically relevant. This review highlights recent advances in elucidating the mechanism of bacterial type I PKSs and associated enzymes, and outlines the ramifications of this knowledge for synthetic biology approaches to expand structural diversity. New insights into biosynthetic codes and structures of thiotemplate systems pave the way to rational bioengineering strategies. Through advances in genome mining, DNA recombination technologies, and biochemical analyses, the toolbox of non-canonical polyketide-modifying enzymes has been greatly enlarged. In addition to various chain-branching and chain-fusing enzymes, an increasing set of scaffold modifying biocatalysts is now available for synthetically hard-to-emulate reactions. © 2015 Elsevier Ltd.

Radmark O.,Karolinska Institutet | Werz O.,Friedrich - Schiller University of Jena | Steinhilber D.,Goethe University Frankfurt | Samuelsson B.,Karolinska Institutet
Biochimica et Biophysica Acta - Molecular and Cell Biology of Lipids | Year: 2015

5-Lipoxygenase (5-LOX) catalyzes two steps in the biosynthesis of leukotrienes (LTs), lipid mediators of inflammation derived from arachidonic acid. In this review we focus on 5-LOX biochemistry including 5-LOX interacting proteins and regulation of enzyme activity. LTs function in normal host defense, and have roles in many disease states where acute or chronic inflammation is part of the pathophysiology, as briefly summarized at the end of this chapter. This article is part of a Special Issue entitled "Oxygenated metabolism of PUFA: analysis and biological relevance. © 2014 Elsevier B.V.All rights reserved.

Buenstorf G.,University of Kassel | Fritsch M.,Friedrich - Schiller University of Jena | Medrano L.F.,Branderstr. 24
Regional Studies | Year: 2015

Buenstorf G., Fritsch M. and Medrano L. F. Regional knowledge, organizational capabilities and the emergence of the West German laser systems industry, 1975–2005, Regional Studies. This paper analyses how the regional distribution of knowledge and pre-existing organizational capabilities shaped the spatial distribution of a new innovative industry, using the German laser systems industry as an empirical example. It is found that regional knowledge in the related field of laser source production and the presence of laser-relevant universities and public research organizations were conducive to the first emergence of laser systems producers. Upstream laser source producers influenced entry into the downstream laser systems industry primarily through their own diversification moves. Public research was less important in the submarket of materials processing laser systems, which is less directly science based than other parts of the laser systems industry. © 2012, Regional Studies Association.

Knoepffler N.,Friedrich - Schiller University of Jena
Onkologe | Year: 2015

Background. Resources are limited in the healthcare services.Conclusion and result. Under such scarcity conditions not all services can be provided, which would be desirable for cancer patients. Rationing of healthcare service violates the principle of human dignity and fundamental rights of the patients with life-threatening diseases such as cancer. Instead by prioritization this violation can be avoided if an ethically correct approach is chosen.Methodology. This paper is based on the literature, e.g. in PubMed and in the Internet. © Springer-Verlag Berlin Heidelberg 2015.

Vogelsberger W.,Friedrich - Schiller University of Jena | Schmidt J.,Friedrich - Alexander - University, Erlangen - Nuremberg
Journal of Physical Chemistry C | Year: 2011

Dissolution experiments are carried out with nanoparticles of barium sulfate in water. An unusual concentration-time behavior is observed. A concentration maximum is measured at the very beginning of the dissolution process. This maximum considerably exceeds the saturation concentration of bulk material. The maximum concentration is followed in time by a decrease of the concentration until the saturation concentration of the bulk material is obtained. This behavior is called kinetic size effect and it is a characteristic of nanoscale particles in general. The colloidal system can be modeled theoretically by thermodynamic and kinetic considerations that cover all processes which may occur in the system: nucleation, particle growth, Ostwald ripening, and dissolution of particles. It has been shown that only the outer surface of the particles is responsible for the dissolution kinetics; it is suggested that the surface of micropores yields no contribution. The dissolution curves observed experimentally follow from the model considerations. It is possible by comparison of experiment and theory to estimate the saturation concentration influenced by the ionic strength in the solution. This effect can be well described by the extended Debye-Hückel law. The measured numerical values of the saturation concentrations are found to be in the range of 4-14 μmol L-1 and therefore in the vicinity of the solubility product of BaSO4. The saturation activity at infinite dilution (I → 0) is aBa = 2.43 ± 0.12 μmol L-1 and the thermodynamic solubility product is KL = 10-11.23. Furthermore, the model calculations provide the possibility to estimate the interfacial tension of the system nanoparticle-solution. The numerical value of 1.1 N m-1 is obtained. The error of the estimated interfacial tension is approximately as large as about 15%. This seems to be acceptable in view of a lack of reliable data in the literature. It is possible furthermore to calculate a kinetic rate constant for any changes that may occur in the colloidal system. The error of this rate constant, however, may be as large as a factor of 10. © 2010 American Chemical Society.

Rhiel E.,Carl von Ossietzky University | Westermann M.,Friedrich - Schiller University of Jena
Protoplasma | Year: 2012

The first successful isolation of discharged ejectisomes from pigmented cryptophytes is reported. Discharged ejectisomes from a Chroomonas and two Cryptomonas species were characterized by transmission electron microscopy using negative staining and freeze-etching. Tubular-shaped fragments of variable lengths and diameters were obtained which showed a paracrystalline lattice. Particle periodicities of 4.1 nm along the longitudinal axis and 3.1 nm in the transverse direction were measured in negative-stained fragments. The dimensions measured from freeze-etched ejectisome fragments were about 0.5-1 nm larger. Sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed a protein banding pattern, dominated by polypeptides of 40-44, 23-25 and 16-18 kDa. The results are discussed in the context of what is currently known about extrusomes of protists. © 2011 Springer-Verlag.

Stark A.,Friedrich - Schiller University of Jena
Energy and Environmental Science | Year: 2011

The combination of the concept of an integrated biorefinery with ionic liquid technology is critically assessed, and potentials for further research and development are identified. © 2011 The Royal Society of Chemistry.

Huang Y.,Chongqing University | Huang Y.,CAS Institute of Physics | Fang Y.,Chalmers University of Technology | Zhang Z.,Institute of Photonic Technology | And 4 more authors.
Light: Science and Applications | Year: 2014

Due to its amazing ability to manipulate light at the nanoscale, plasmonics has become one of the most interesting topics in the field of light-matter interaction. As a promising application of plasmonics, surface-enhanced Raman scattering (SERS) has been widely used in scientific investigations and material analysis. The large enhanced Raman signals are mainly caused by the extremely enhanced electromagnetic field that results from localized surface plasmon polaritons. Recently, a novel SERS technology called remote SERS has been reported, combining both localized surface plasmon polaritons and propagating surface plasmon polaritons (PSPPs, or called plasmonic waveguide), which may be found in prominent applications in special circumstances compared to traditional local SERS. In this article, we review the mechanism of remote SERS and its development since it was first reported in 2009. Various remote metal systems based on plasmonic waveguides, such as nanoparticle-nanowire systems, single nanowire systems, crossed nanowire systems and nanowire dimer systems, are introduced, and recent novel applications, such as sensors, plasmon-driven surface-catalyzed reactions and Raman optical activity, are also presented. Furthermore, studies of remote SERS in dielectric and organic systems based on dielectric waveguides remind us that this useful technology has additional, tremendous application prospects that have not been realized in metal systems.© 2014 CIOMP. All rights reserved 2047-7538/14.

Johnson-McDaniel N.K.,Friedrich - Schiller University of Jena | Johnson-McDaniel N.K.,Tata Institute of Fundamental Research | Shah A.G.,University of Southampton | Whiting B.F.,University of Florida
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

It is now possible to compute linear in mass-ratio terms in the post-Newtonian (PN) expansion for compact binaries to very high orders using linear black hole perturbation theory applied to various invariants. For instance, a computation of the redshift invariant of a point particle in a circular orbit about a black hole in linear perturbation theory gives the linear-in-mass-ratio portion of the binding energy of a circular binary with an arbitrary mass ratio. This binding energy, in turn, encodes the system's conservative dynamics. We give a method for extracting the analytic forms of these post-Newtonian coefficients from high-accuracy numerical data using experimental mathematics techniques, notably an integer relation algorithm. Such methods should be particularly important when the calculations progress to the considerably more difficult case of perturbations of the Kerr metric. As an example, we apply this method to the redshift invariant in the Schwarzschild metric. Here, we obtain analytic coefficients to 12.5PN order and higher-order terms in mixed analytic-numerical form to 21.5PN, including analytic forms for the complete 13.5PN coefficient and all the logarithmic terms at 13PN. We have computed the individual modes to over 5000 digits, of which we use at most 1240 in the present calculation. At these high orders, an individual coefficient can have over 30 terms, including a wide variety of transcendental numbers, when written out in full. We are still able to obtain analytic forms for such coefficients from the numerical data through a careful study of the structure of the expansion. The structure we find also allows us to predict certain "leading logarithm"-type contributions to all orders. The additional terms in the expansion we obtain improve the accuracy of the PN series for the redshift observable, even in the very strong-field regime inside the innermost stable circular orbit, particularly when combined with exponential resummation. © 2015 American Physical Society.

Bernuzzi S.,California Institute of Technology | Bernuzzi S.,University of Parma | Dietrich T.,Friedrich - Schiller University of Jena | Nagar A.,Institute des Hautes etudes Scientifiques
Physical Review Letters | Year: 2015

In the context of neutron star mergers, we study the gravitational wave spectrum of the merger remnant using numerical relativity simulations. Postmerger spectra are characterized by a main peak frequency f2 related to the particular structure and dynamics of the remnant hot hypermassive neutron star. We show that f2 is correlated with the tidal coupling constant κ2T that characterizes the binary tidal interactions during the late-inspiral merger. The relation f22T) depends very weakly on the binary total mass, mass ratio, equation of state, and thermal effects. This observation opens up the possibility of developing a model of the gravitational spectrum of every merger unifying the late-inspiral and postmerger descriptions. © 2015 American Physical Society.

Reisch C.,University of Regensburg | Bernhardt-Romermann M.,University of Regensburg | Bernhardt-Romermann M.,Friedrich - Schiller University of Jena
Plant Ecology | Year: 2014

In this study, we analysed the impact of study design and life history traits on genetic variation of plants determined with amplified fragment length polymorphisms (AFLPs), a technique widely applied in all fields of molecular plant ecology. For the proper interpretation and comparison of genetic variation based upon AFLPs, a meta-analysis based upon a large number of studies of the relationship between study design and plant life history traits on the one hand and of AFLP variation on the other hand is needed but is lacking. To bridge this gap, we extracted data on study design and genetic variation from 115 AFLP studies comprising a total of 152 species. Subsequently, we ascribed the life history traits taxonomic status, life span, frequency, mating system and pollination vector to each of the species. Then, we used linear models to analyse the impact of study design and life history traits on genetic variation. In our data set genetic variation within and among populations depended neither on the number of analysed populations nor the number of analysed individuals per population. However, maximum geographic distance between populations strongly affected genetic variation. Variation within populations decreased while variation among populations increased with maximum geographic distance. Concerning the impact of life history traits, both genetic variation within and among populations depended with increasing strength on the life span, the frequency and the mating system of the species. Following the results of this study, the number of analysed populations or individuals per population is not necessarily a problem when comparing results of different studies, at least when not very low sample sizes are used. However, corresponding study ranges would be highly recommendable, since the maximum geographic distance between populations strongly affects genetic variation. © 2014, Springer Science+Business Media Dordrecht.

Reese G.,Friedrich - Schiller University of Jena | Jacob L.,Saarland University
Environmental Science and Policy | Year: 2015

Beliefs about environmental justice are an important aspect in the willingness to continuously commit to pro-environmental behaviors and actions both on individual and societal levels. Since environmental policy is subject to decisions across various state institutions, the current article focuses on three principles of environmental justice beliefs, and tests their independent contributions toward pro-environmental behavior. In a representative sample of German citizens, we tested the effects of intergenerational justice, ecological justice and global justice beliefs on pro-environmental intentions. In addition, we focused on two potential processes that might explain the relation between justice beliefs and pro-environmental behavior, namely, moral anger and perceived responsibility. In line with expectations, stronger environmental justice beliefs predicted pro-environmental intentions. Path analyses further revealed that sense of responsibility and moral anger mediated the effects, with the former being a stronger predictor of pro-environmental intentions than the latter. These findings are discussed in light of current societal debate and policy recommendations are exemplified. © 2015 Elsevier Ltd.

Weirich M.,Friedrich - Schiller University of Jena | Fuchs S.,Center for General Linguistics
Journal of Speech, Language, and Hearing Research | Year: 2013

Purpose: The purpose of this study was to further explore the understanding of speaker-specific realizations of the /s/-/∫ / contrast in German in relation to individual differences in palate shape. Method: Two articulatory experiments were carried out with German native speakers. In the first experiment, 4monozygotic and 2 dizygotic twin pairs were recorded by means of electromagnetic articulography. In the second experiment, 12 unrelated speakers were recorded by means of electropalatography. Interspeaker variability in the articulatory distance between the sibilants was measured and was correlated with several parameters of the palate shape. Results: The results were twofold: (a) Similar palatal morphologies as found in monozygotic twins yield similar articulatory realizations of the /s/-/∫ / contrast regarding vertical and horizontal distance of the target tongue tip positions, and (b) the realization of the contrast was influenced by palatal steepness, especially the inclination angle of the alveolo-palatal region. Speakers with flat inclination angles mainly retracted their tongue to realize the contrast, whereas speakers with steep inclination angles also elevated their tongue. Conclusion: The articulatory realization of the sibilant contrast is influenced not only by speaker-specific auditory acuity, as previously observed, but also by palatal shape morphology, which affects the somatosensory feedback speakers receive. © American Speech-Language-Hearing Association.

Gruber R.,Leibniz Institute for Age Research | Gruber R.,Cancer Research UK Research Institute | Zhou Z.,Leibniz Institute for Age Research | Sukchev M.,Leibniz Institute for Age Research | And 4 more authors.
Nature Cell Biology | Year: 2011

Primary microcephaly 1 is a neurodevelopmental disorder caused by mutations in the MCPH1 gene, whose product MCPH1 (also known as microcephalin and BRIT1) regulates DNA-damage response. Here we show that Mcph1 disruption in mice results in primary microcephaly, mimicking human MCPH1 symptoms, owing to a premature switching of neuroprogenitors from symmetric to asymmetric division. MCPH1-deficiency abrogates the localization of Chk1 to centrosomes, causing premature Cdk1 activation and early mitotic entry, which uncouples mitosis and the centrosome cycle. This misorients the mitotic spindle alignment and shifts the division plane of neuroprogenitors, to bias neurogenic cell fate. Silencing Cdc25b, a centrosome substrate of Chk1, corrects MCPH1-deficiency-induced spindle misalignment and rescues the premature neurogenic production in Mcph1-knockout neocortex. Thus, MCPH1, through its function in the Chk1-Cdc25-Cdk1 pathway to couple the centrosome cycle with mitosis, is required for precise mitotic spindle orientation and thereby regulates the progenitor division mode to maintain brain size. © 2011 Macmillan Publishers Limited. All rights reserved.

Kostiainen M.A.,Radboud University Nijmegen | Pietsch C.,Friedrich - Schiller University of Jena | Hoogenboom R.,Ghent University | Nolte R.J.M.,Radboud University Nijmegen | Cornelissen J.J.L.M.,University of Twente
Advanced Functional Materials | Year: 2011

Here a method is presented for the temperature-switchable assembly of viral particles into large hierarchical complexes. Dual-functional diblock copolymers consisting of poly(diethyleneglycol methyl ether methacrylate) (poly(DEGMA)) and poly((2-dimethylamino)ethyl methacrylate) (poly(DMAEMA)) blocks self-assemble electrostatically with cowpea chlorotic mottle virus (CCMV) particles into micrometer-sized objects as a function of temperature. The poly(DMAEMA) block carries a positive charge, which can interact electrostatically with the negatively charged outer surface of the CCMV capsid. When the solution temperature is increased above 40 °C, to cross the cloud point temperature (T cp) of the DEGMA block, the polymer chains collapse on the surface of the virus particle, which makes them partially hydrophobic, and consequently causes the formation of large hierarchical assemblies. Disassembly of the virus-polymer complexes can be induced by reducing the solution temperature below the T cp, which allows the poly(DEGMA) blocks to rehydrate and free virus particles to be released. The assembly process is fully reversible and can sustain several heating-cooling cycles. Importantly, this method relies on reversible supramolecular interactions and therefore avoids the irreversible covalent modification of the particle surface. This study illustrates the potential of temperature-responsive polymers for controlled binding and releasing of virus particles. Hot get-together party of viruses: Temperature-responsive diblock copolymer binds electrostatically onto the surface of viral capsids and self-assembles with the virus particles into micrometer-sized objects when the solution is heated above the cloud point temperature (T cp) of the polymer. Below the T cp, only free individual virus particles are observed. The assembly process is fully reversible and can sustain several heating-cooling cycles, and therefore offers a supramolecular method to control the assembly and release of charged biomolecules. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Schobel K.,Friedrich - Schiller University of Jena | Veselov A.P.,Loughborough University | Veselov A.P.,Moscow State University
Communications in Mathematical Physics | Year: 2015

We show that the orthogonal separation coordinates on the sphere Sn are naturally parametrised by the real version of the Deligne–Mumford–Knudsen moduli space $${\bar{M}_{0,n+2}({\mathbb{R}})}$$M¯0,n+2(R) of stable curves of genus zero with n + 2 marked points. We use the combinatorics of Stasheff polytopes tessellating $${\bar{M}_{0,n+2}({\mathbb{R}})}$$M¯0,n+2(R) to classify the different canonical forms of separation coordinates and deduce an explicit construction of separation coordinates, as well as of Stäckel systems from the mosaic operad structure on $${\bar{M}_{0,n+2}({\mathbb{R}})}$$M¯0,n+2(R). © 2015, Springer-Verlag Berlin Heidelberg.

Bernuzzi S.,California Institute of Technology | Bernuzzi S.,University of Parma | Nagar A.,Institute des Hautes etudes Scientifiques | Dietrich T.,Friedrich - Schiller University of Jena | Damour T.,Institute des Hautes etudes Scientifiques
Physical Review Letters | Year: 2015

The data analysis of the gravitational wave signals emitted by coalescing neutron star binaries requires the availability of an accurate analytical representation of the dynamics and waveforms of these systems. We propose an effective-one-body model that describes the general relativistic dynamics of neutron star binaries from the early inspiral up to the merger. Our effective-one-body model incorporates an enhanced attractive tidal potential motivated by recent analytical advances in the post-Newtonian and gravitational self-force description of relativistic tidal interactions. No fitting parameters are introduced for the description of tidal interaction in the late, strong-field dynamics. We compare the model energetics and the gravitational wave phasing with new high-resolution multiorbit numerical relativity simulations of equal-mass configurations with different equations of state. We find agreement within the uncertainty of the numerical data for all configurations. Our model is the first semianalytical model that captures the tidal amplification effects close to merger. It thereby provides the most accurate analytical representation of binary neutron star dynamics and waveforms currently available. © 2015 American Physical Society.

Kuppers B.-O.,Friedrich - Schiller University of Jena
Current Topics in Microbiology and Immunology | Year: 2016

The analysis of the inherent context-dependence of genetic information suggests that there are evolutionary mechanisms which are independent of the processes of environmental adaptation and yet are able to push prebiotic matter towards functional complexity. In this regard, the extension of information space, by random prolongation of the primary structure of biological macromolecules, must have played a decisive role in the origin of life. On the one hand, the extension of information space is tantamount to an increase in the syntactic complexity of potential information carriers, which in turn is a prerequisite for the nucleation and evolution of semantic information. On the other hand, the increase in the dimensionality of information space expands the number of possible pathways of evolutionary optimisation and thereby improves the possible choices that can be made by progressive evolution. Alongside the optimisation of evolutionary optimisation itself, there are principles of evolutionary dynamics that direct the formation of functional order in prebiotic matter. Since these principles are constitutive for the proto-semantics of genetic information, they may be regarded as the elements of the semantic code of evolution. © Springer International Publishing Switzerland 2015.

Wiese H.,Friedrich - Schiller University of Jena
Frontiers in Human Neuroscience | Year: 2013

We are typically more accurate at remembering own- than other-race faces. This own-race bias has been suggested to result from enhanced expertise with and more efficient perceptual processing of own-race than other-race faces. In line with this idea, the N170, an event-related potential correlate of face perception, has been repeatedly found to be larger for other-race faces. Other studies, however, found no difference in N170 amplitude for faces from diverse ethnic groups. The present study tested whether these seemingly incongruent findings can be explained by varying task demands. European participants were presented with upright and inverted European and Asian faces (as well as European and Asian houses), and asked to either indicate the ethnicity or the orientation of the stimuli. Larger N170s for other-race faces were observed in the ethnicity but not in the orientation task, suggesting that the necessity to process facial category information is a minimum prerequisite for the occurrence of the effect. In addition, N170 inversion effects, with larger amplitudes for inverted relative to upright stimuli, were more pronounced for own- relative to other-race faces in both tasks. Overall, the present findings suggest that the occurrence of ethnicity effects in N170 for upright faces depends on the amount of facial detail required for the task at hand. At the same time, the larger inversion effects for own- than other-race faces occur independent of task and may reflect the fine-tuning of perceptual processing to faces of maximum expertise. © 2013 Wiese.

Dietrich T.,Friedrich - Schiller University of Jena | Bernuzzi S.,California Institute of Technology | Bernuzzi S.,University of Parma
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

We reexamine the gravitational collapse of rotating neutron stars to black holes by new 3+1 numerical relativity simulations employing the Z4c formulation of Einstein equations, the moving puncture gauge conditions, and a conservative mesh refinement scheme for the general relativistic hydrodynamics. The end state of the collapse is compared to the vacuum spacetime resulting from the evolution of spinning puncture initial data. Using a local analysis for the metric fields, we demonstrate that the two spacetimes actually agree. Gravitational waveforms are analyzed in some detail. We connect the emission of radiation to the collapse dynamics using simplified spacetime diagrams, and discuss the similarity of the waveform structure with the one of black hole perturbation theory. © 2015 American Physical Society.

Zandler H.,University of Bayreuth | Brenning A.,University of Waterloo | Brenning A.,University of Heidelberg | Brenning A.,Friedrich - Schiller University of Jena | Samimi C.,University of Bayreuth
Remote Sensing of Environment | Year: 2015

Remote sensing based biomass estimation in arid environments is essential for monitoring degradation and carbon dynamics. However, due to the low vegetation cover in these regions, satellite-based research is challenging. Numerous potentially useful remotely-sensed predictor variables have been proposed, and several statistical and machine-learning techniques are available for empirical spatial modeling, but their predictive performance is yet unknown in this context. We therefore modeled total biomass in the Eastern Pamirs of Tajikistan, a region with extremely low vegetation cover, with a large set of satellite based predictors derived from two commonly used sensors (Landsat OLI, RapidEye), and assessed their utility in this environment using several suitable modeling approaches (stepwise, lasso, partial least squares and ridge regression, random forest). The best performing model (lasso regression) resulted in a RMSE of 992kgha-1 in spatial cross-validation, indicating that biomass quantification in this arid setting is feasible but subject to large uncertainties. Furthermore, pronounced over-fitting in some commonly used models (e.g. stepwise regression, random forest) underlined the importance of adequate variable selection and shrinkage techniques in spatial modeling of high dimensional data. The applied sensors showed very similar performance and a combination of both only slightly improved results of better performing models. A permutation-based assessment of variable importance showed that some of the most frequently used vegetation indices are not suitable for dwarf shrub biomass prediction in this environment. We suggest that predictor variables based on several bands accounting for vegetation as well as background information are required in this arid setting. © 2014 Elsevier Inc.

Singh P.,Institute of Photonic Technology | Deckert V.,Institute of Photonic Technology | Deckert V.,Friedrich - Schiller University of Jena
Chemical Communications | Year: 2014

Localized protonation of 4-mercaptopyridine (4-MPY), activated by light in the presence of silver nanoparticles is monitored under ambient conditions using surface-enhanced Raman scattering (SERS) and tip-enhanced Raman scattering (TERS). The reaction can be controlled by the excitation wavelength and the atmospheric conditions, thus, providing a tool for site-specific control of protonation. © 2014 the Partner Organisations.

Irintchev A.,Friedrich - Schiller University of Jena
Annals of Anatomy | Year: 2011

Restoration of function after peripheral nerve repair in humans is unsatisfactory. Various causes of poor recovery have been proposed. Still, we do not understand which of these potential factors are indeed detrimental and do not know how to manipulate them experimentally in a clinically feasible way. Future success largely depends on methodological improvement in rodent models. An example of recent progress is the introduction of new functional and anatomical outcome measures in the facial nerve injury paradigm which led to novel insights into facial nerve regeneration and a new therapeutic concept. Less success can be ascribed to the use of the classical spinal nerve model, the sciatic nerve paradigm, not least because of its anatomical and functional complexity making assessment of recovery challenging. A simpler alternative to the sciatic nerve is the femoral nerve model. It offers, alongside with its known usefulness for studies on precision of motor reinnervation, the possibility of reliable functional assessments and a straightforward search of anatomical substrates of dysfunction. The structure-function approach in the femoral nerve paradigm has been useful for testing of novel therapeutic means and analyses of regeneration in mutant mice. The potential of the method has still not been really exploited and its more extensive use may contribute to better understanding of nerve regeneration. © 2011 Elsevier GmbH.

Maas A.,Friedrich - Schiller University of Jena
Modern Physics Letters A | Year: 2012

The concept of (global) gauge symmetry breaking plays an important role in many areas of physics. Since the corresponding symmetry is a gauge symmetry, its breaking is actually gauge-dependent. Thus, it is possible to design gauges which restore the symmetry as good as possible. Such gauge constructions will be detailed here, illustrated with the use of lattice gauge theory. Their use will be discussed for the cases of the Higgs effect, high-baryon density color superconductors, and BRST symmetry. © 2012 World Scientific Publishing Company.

Beck J.,University of Basel | Brehm G.,Friedrich - Schiller University of Jena | Fiedler K.,University of Vienna
Biotropica | Year: 2011

Ideas on the spatial variation of biodiversity often imply a causal link between the abundance and species richness of organisms. We investigated this 'more individuals hypothesis' using light-trapping data of three unrelated groups of moths (Arctiidae, Geometridae and Pyraloidea) from the Ecuadorian Andes. We analyzed environmental correlates of specimen densities found in different habitats, finding effects of temperature, moonlight, forest succession, elevation and season. We corrected abundance data for light-trapping artefacts, and we measured species diversity with various metrics known to be unbiased by undersampling. We found significant positive correlations between abundance and species diversity for all three taxonomic groups. We discuss implications for a general evaluation of species-energy theory as well as for a better understanding of ecological processes in montane habitats of the Andes. Abstract in Spanish is available at © 2010 The Author(s). Journal compilation © 2010 by The Association for Tropical Biology and Conservation.

Dirnberger M.,University of Graz | Gattringer C.,University of Graz | Maas A.,Friedrich - Schiller University of Jena
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2012

We study the behavior of center sectors in pure SU(4) lattice gauge theory at finite temperature. The center sectors are defined as spatial clusters of neighboring sites with values of their local Polyakov loops near the same center elements. We study the connectedness and percolation properties of the center clusters across the deconfinement transition. We show that for SU(4) gauge theory deconfinement cannot be described as a percolation transition of center clusters, a finding which is different from pure SU(2) or pure SU(3) Yang-Mills theory, where the percolation description even allows for a continuum limit. © 2012 Elsevier B.V.

Kiefer T.,Friedrich - Schiller University of Jena | Schlegel T.,Helmholtz Center for Heavy Ion Research
Physics of Plasmas | Year: 2012

It is shown that the hydrodynamic model of a one-dimensional collisionless plasma expansion is contained in the kinetic description as a special case. This belongs to a specific choice for the electron distribution function. Moreover, the consequences of the use of the hydrodynamic approach regarding the temporal evolution of the electron phase space density are investigated. It turns out that only the case of a hydrodynamic description with the adiabatic constant κ 3 is physically self-consistent. Numerical simulations confirm this argumentation. The analysis for the case κ 3 is extended to the kinetics of a relativistic electron gas. © 2012 American Institute of Physics.

Gies H.,Friedrich - Schiller University of Jena | Gies H.,University of Heidelberg
Lecture Notes in Physics | Year: 2012

This lecture course is intended to fill the gap between graduate courses on quantum field theory and specialized reviews or forefront-research articles on functional renormalization group approaches to quantum field theory and gauge theories. © 2012 Springer-Verlag Berlin Heidelberg.

Melzer R.,University College Dublin | Theissen G.,Friedrich - Schiller University of Jena
Annals of Botany | Year: 2016

Background The origin of new species and of new forms is one of the fundamental characteristics of evolution. However, the mechanisms that govern the diversity and disparity of lineages remain poorly understood. Particularly unclear are the reasons why some taxa are vastly more species-rich than others and the manner in which species diversity and morphological disparity are interrelated. Scope and Conclusions Evolutionary innovations and ecological opportunities are usually cited as among the major factors promoting the evolution of species diversity. In many cases it is likely that these factors are positively reinforcing, with evolutionary innovations creating ecological opportunities that in turn foster the origin of new innovations. However, we propose that a third factor, developmental robustness, is very often essential for this reinforcement to be effective. Evolutionary innovations need to be stably and robustly integrated into the developmental genetic programme of an organism to be a suitable substrate for selection to 'explore' ecological opportunities and morphological 'design' space (morphospace). In particular, we propose that developmental robustness of the bauplan is often a prerequisite for the exploration of morphospace and to enable the evolution of further novelties built upon this bauplan. Thus, while robustness may reduce the morphological disparity at one level, it may be the basis for increased morphological disparity and for evolutionary innovations at another level, thus fostering species diversity. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company.

Huber M.Q.,TU Darmstadt | Maas A.,Friedrich - Schiller University of Jena | Von Smekal L.,TU Darmstadt
Journal of High Energy Physics | Year: 2012

We investigate the Dyson-Schwinger equations for the gluon and ghost propagators and the ghost-gluon vertex of Landau-gauge gluodynamics in two dimensions. While this simplifies some aspects of the calculations as compared to three and four dimensions, new complications arise due to a mixing of different momentum regimes. As a result, the solutions for the propagators are more sensitive to changes in the three-point functions and the ansätze used for them at the leading order in a vertex expansion. Here, we therefore go beyond this common truncation by including the ghost-gluon vertex self-consistently for the first time, while using a model for the three-gluon vertex which reproduces the known infrared asymptotics and the zeros at intermediate momenta as observed on the lattice. A separate computation of the three-gluon vertex from the results is used to confirm the stability of this behavior a posteriori. We also present further arguments for the absence of the decoupling solution in two dimensions. Finally, we show how in general the infrared exponent κ of the scaling solutions in two, three and four dimensions can be changed by allowing an angle dependence and thus an essential singularity of the ghost-gluon vertex in the infrared. © 2012 SISSA, Trieste, Italy.

Cantner U.,Friedrich - Schiller University of Jena | Cantner U.,University of Southern Denmark | Rake B.,University of Passau
Research Policy | Year: 2014

Knowledge production and scientific research have become increasingly more collaborative and international, particularly in pharmaceuticals. We analyze this tendency in general and tie formation in international research networks on the country level in particular. Based on a unique dataset of scientific publications related to pharmaceutical research and applying social network analysis, we find that both the number of countries and their connectivity increase in almost all disease group specific networks. The cores of the networks consist of high income OECD countries and remain rather stable over time. Using network regression techniques to analyze the network dynamics our results indicate that accumulative advantages based on connectedness and multi-connectivity are positively related to changes in the countries' collaboration intensity whereas various indicators on similarity between countries do not allow for unambiguous conclusions. © 2013 Elsevier B.V. All rights reserved.

Braig C.,Friedrich - Schiller University of Jena | Predehl P.,Max Planck Institute for Extraterrestrial Physics
Applied Optics | Year: 2012

We develop an analytical approach to refractive, blazed diffractive, and achromatic x-ray lenses of scalable dimensions for energies from 1 to 20 keV. Based on the parabolic wave equation, their wideband imaging properties are compared and optimized for a given spectral range. Low-Z lens materials for massive cores and rugged alternatives, such as polycarbonate or Si for flat Fresnel components, are investigated with respect to their suitability for diffraction-limited high-energy astronomy. Properly designed "hybrid" combinations can serve as an approach to x-ray telescopes with an enhanced efficiency throughout the whole considered band, nearly regardless of their inherent absorption. © 2012 Optical Society of America.

Zumbusch G.,Friedrich - Schiller University of Jena
Proceedings - 2012 11th International Symposium on Parallel and Distributed Computing, ISPDC 2012 | Year: 2012

Current CPU and GPU architectures heavily use data and instruction parallelism at different levels. Floating point operations are organised in vector instructions of increasing vector length. For reasons of performance it is mandatory to use the vector instructions efficiently. Several ways of tuning a model problem finite difference stencil computation are discussed. The combination of vectorisation and an interleaved data layout, cache aware algorithms, loop unrolling, parallelisation and parameter tuning lead to optimised implementations at a level of 90% peak performance of the floating point pipelines on recent Intel Sandy Bridge and AMD Bulldozer CPU cores, both with AVX vector instructions as well as on Nvidia Fermi/ Kepler GPU architectures. Furthermore, we present numbers for parallel multi-core/ multi-processor and multi-GPU configurations. They represent regularly more than an order of speed up compared to a standard implementation. The analysis may also explain deficiencies of automatic vectorisation for linear data layout and serve as a foundation of efficient implementations of more complex expressions. © 2012 IEEE.

Ehrt D.,Friedrich - Schiller University of Jena
Physics and Chemistry of Glasses: European Journal of Glass Science and Technology Part B | Year: 2013

Zinc and manganese borates and borosilicates were prepared and investigated. Binary ZnO-B2O3 and MnO-B2O 3 melts show similar stable phase separation below 50 mol% ZnO or MnO. Two layers were separated in the melts. The upper layer was nearly pure B2O3 and contained crystals. The lower layer was zinc or manganese borate with around 50 mol% ZnO or MnO. Melts of ternary systems with SiO2 were separated into SiO2 rich and zinc or manganese rich phases. The addition of Na2O decreases phase separation. Compositions with more than 50 mol% ZnO provided clear homogeneous glass samples. Mn2+ was substituted for Zn2+ in glasses and crystals, with a coordination number from 6 to 4, and a variation of Mn 2+ photoluminescence from orange-red to yellow-green depending on local structure. A drastic change of luminescence was detected when the glass was transformed to a glass ceramic by thermal treatment. Adding Eu 2O3 or Tb2O3 to zinc borates provides strong orange-red (Eu3+) or green (Tb3+) luminescence. In phase separated samples, Mn2+, Eu3+ and Tb3+ were only accumulated in the zinc borate and not in the B 2O3 phase. The large Eu3+ and Tb3+ ions could not substitute for Zn2+ in the crystal phases.

Zimmer T.,Friedrich - Schiller University of Jena
Marine Drugs | Year: 2010

The human genome encodes nine functional voltage-gated Na+ channels. Three of them, namely Nav1.5, Nav1.8, and Nav1.9, are resistant to nanomolar concentrations of tetrodotoxin (TTX; IC50 ≥ 1 μ M). The other isoforms, which are predominantly expressed in the skeletal muscle and nervous system, are highly sensitive to TTX (IC50 - 10 nM). During the last two decades, it has become evident that in addition to the major cardiac isoform Nav1.5, several of those TTX sensitive isoforms are expressed in the mammalian heart. Whereas immunohistochemical and electrophysiological methods demonstrated functional expression in various heart regions, the physiological importance of those isoforms for cardiac excitation in higher mammals is still debated. This review summarizes our knowledge on the systemic cardiovascular effects of TTX in animals and humans, with a special focus on cardiac excitation and performance at lower concentrations of this marine drug. Altogether, these data strongly suggest that TTX sensitive Na + channels, detected more recently in various heart tissues, are not involved in excitation phenomena in the healthy adult heart of higher mammals. © 2010 by the authors; licensee Molecular Diversity Preservation International.

Seider K.,Leibniz Institute for Natural Product Research and Infection Biology | Heyken A.,Leibniz Institute for Natural Product Research and Infection Biology | Luttich A.,Leibniz Institute for Natural Product Research and Infection Biology | Miramon P.,Leibniz Institute for Natural Product Research and Infection Biology | And 2 more authors.
Current Opinion in Microbiology | Year: 2010

Pathogenic yeasts, either from the environment or the normal flora, have to face phagocytic cells that constitute the first line of defence during infection. In order to evade or counteract attack by phagocytes, pathogenic yeasts have acquired a repertoire of strategies to survive, colonize and infect the host. In this review we focus on the interaction of yeasts, such as Candida, Histoplasma or Cryptococcus species, with macrophages or neutrophils. We discuss strategies used by these fungi to prevent phagocytosis or to counteract phagocytic activities. We go on to describe the strategies that permit intracellular survival within phagocytes and that may eventually lead to damage of and escape from the phagocyte. © 2010 Elsevier Ltd.

Beckmann M.,Friedrich - Schiller University of Jena
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2015

We consider a single-player game where a particle on a board has to be steered to evacuation cells. The actor has no direct control over this particle but may indirectly influence the movement of the particle by blockades. We examine optimal blocking strategies and the recurrence property experimentally and conclude that the random walk of our game is recurrent. Furthermore, we are interested in the average time in which an evacuation cell is reached. © Springer International Publishing Switzerland 2015.

Xu Z.,Leibniz Institute for Natural Product Research and Infection Biology | Baunach M.,Leibniz Institute for Natural Product Research and Infection Biology | Ding L.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Friedrich - Schiller University of Jena
Angewandte Chemie - International Edition | Year: 2012

Getting indole terpenes into shape: Genetic analysis, pathway dissection, and heterologous reconstitution provide first insights into bacterial indolosesquiterpenoid biosynthesis and unveil the involvement of a new type of terpene cyclase and an indole oxygenase in the formation of indosespene, xiamycin, and sespenine ring systems. Furthermore, heterologous pathway expression led to the discovery of C-C- and C-N-linked xiamycin dimers. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Schaible H.-G.,Friedrich - Schiller University of Jena
Arthritis Research and Therapy | Year: 2014

Proinflammatory cytokines are major mediators in the pathogenesis of diseases of joints such as rheumatoid arthritis and osteoarthritis. This review emphasizes that proinflammatory cytokines such as tumor necrosis factor-alpha, interleukin-1beta, interleukin-6 and interleukin-17 are also mediators of pain by directly acting on the nociceptive system. Proportions of nociceptive sensory neurons express receptors for these cytokines, and the application of cytokines rapidly changes the excitability, ion currents and second messenger systems of these neurons. By inducing persistent sensitization of nociceptive sensory neurons (C- and a proportion of Aδ-fibers) for mechanical stimuli in the joint (a process called peripheral sensitization), these cytokines significantly contribute to the persistent hyperalgesia typical for many disease states of the joint. In addition, the disease-associated release of cytokines in the spinal cord supports the generation of central sensitization. The therapeutic neutralization of proinflammatory cytokines thus not only reduces the process of inflammation but may directly reduce hyperalgesia and pain by reversing the neuronal effects of cytokines. It is emerging that different cytokines have different actions on neurons. The neutralization of tumor necrosis factor-alpha reduces both mechanical and thermal hyperalgesia of the joint. The neutralization of interleukin-1beta attenuates thermal hyperalgesia whereas the neutralization of interleukin-6 and interleukin-17 mainly reduces mechanical hyperalgesia. These different effects are partly explained by influencing different target molecules in sensory neurons. For example, in cultured sensory neurons tumor necrosis factor-alpha and interleukin-1beta upregulate the TRPV1 ion channel, which is involved in the transduction of heat stimuli, consistent with an effect of these cytokines in thermal hyperalgesia. By contrast, interleukin-17 upregulates the TRPV4 ion channel, which has a role in the transduction of mechanical stimuli. Thus, the analgesic potential of neutralizing cytokines seems to depend on which cytokine is mainly involved in the particular pain state.

Ishida K.,Leibniz Institute for Natural Product Research and Infection Biology | Lincke T.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Friedrich - Schiller University of Jena
Angewandte Chemie - International Edition | Year: 2012

Decoded before decay: Cryptic and highly unstable polyketide metabolites, thailandamidesA and B, were isolated from Burkholderia thailandensis, and their absolute configurations fully elucidated using a combination of chemical degradation, bioinformatics, NMR spectroscopy, precursor-directed biosynthesis, and analysis of pathway intermediates (see scheme). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Behnken S.,Leibniz Institute for Natural Product Research and Infection Biology | Lincke T.,Leibniz Institute for Natural Product Research and Infection Biology | Kloss F.,Leibniz Institute for Natural Product Research and Infection Biology | Ishida K.,Leibniz Institute for Natural Product Research and Infection Biology | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2012

Anti-Terminator: Rise of the Molecules: Overexpression of an antiterminator gene (nusG) in Clostridium cellulolyticum induced the biosynthesis of the novel antibiotic closthioamide and related thioamides. This is the first successful genetic engineering of an anaerobe to trigger a cryptic pathway. Furthermore, synthetic probes provide valuable insights into the biogenetic relationship of the rare thioamide metabolites. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Schlattmann P.,Friedrich - Schiller University of Jena | Dirnagl U.,Charite - Medical University of Berlin
Journal of Cerebral Blood Flow and Metabolism | Year: 2010

A common setting in experimental cerebrovascular research is the comparison of more than two experimental groups. Often, continuous measures such as infarct volume, cerebral blood flow, or vessel diameter are the primary variables of interest. This article presents the principles of the statistical analysis of comparing more than two groups using analysis of variance (ANOVA). We will also explain post hoc comparisons, which are required to show which groups significantly differ once ANOVA has rejected the null hypothesis. Although statistical packages perform ANOVA and post hoc contrast at a key stroke, in this study, we use examples from experimental stroke research to reveal the simple math behind the calculations and the basic principles. This will enable the reader to understand and correctly interpret the readout of statistical packages and to help prevent common errors in the comparison of multiple means. © 2010 ISCBFM All rights reserved.

Brauer D.S.,Friedrich - Schiller University of Jena
Angewandte Chemie - International Edition | Year: 2015

Bioactive glasses were the first synthetic materials to show bonding to bone, and they are successfully used for bone regeneration. They can degrade in the body at a rate matching that of bone formation, and through a combination of apatite crystallization on their surface and ion release they stimulate bone cell proliferation, which results in the formation of new bone. Despite their excellent properties and although they have been in clinical use for nearly thirty years, their current range of clinical applications is still small. Latest research focuses on developing new compositions to address clinical needs, including glasses for treating osteoporosis, with antibacterial properties, or for the sintering of scaffolds with improved mechanical stability. This Review discusses how the glass structure controls the properties, and shows how a structure-based design may pave the way towards new bioactive glass implants for bone regeneration. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Voigt A.,Leibniz Institute for Natural Product Research and Infection Biology | Schofl G.,Leibniz Institute for Natural Product Research and Infection Biology | Saluz H.P.,Leibniz Institute for Natural Product Research and Infection Biology | Saluz H.P.,Friedrich - Schiller University of Jena
PLoS ONE | Year: 2012

Background: Chlamydiaceae are a family of obligate intracellular pathogens causing a wide range of diseases in animals and humans, and facing unique evolutionary constraints not encountered by free-living prokaryotes. To investigate genomic aspects of infection, virulence and host preference we have sequenced Chlamydia psittaci, the pathogenic agent of ornithosis. Results: A comparison of the genome of the avian Chlamydia psittaci isolate 6BC with the genomes of other chlamydial species, C. trachomatis, C. muridarum, C. pneumoniae, C. abortus, C. felis and C. caviae, revealed a high level of sequence conservation and synteny across taxa, with the major exception of the human pathogen C. trachomatis. Important differences manifest in the polymorphic membrane protein family specific for the Chlamydiae and in the highly variable chlamydial plasticity zone. We identified a number of psittaci-specific polymorphic membrane proteins of the G family that may be related to differences in host-range and/or virulence as compared to closely related Chlamydiaceae. We calculated non-synonymous to synonymous substitution rate ratios for pairs of orthologous genes to identify putative targets of adaptive evolution and predicted type III secreted effector proteins. Conclusions: This study is the first detailed analysis of the Chlamydia psittaci genome sequence. It provides insights in the genome architecture of C. psittaci and proposes a number of novel candidate genes mostly of yet unknown function that may be important for pathogen-host interactions. © 2012 Voigt et al.

Miklos B.,ETH Zurich | Giesen J.,Friedrich - Schiller University of Jena | Pauly M.,ETH Zurich
ACM Transactions on Graphics | Year: 2010

This paper addresses the fundamental problem of computing stable medial representations of 3D shapes. We propose a spatially adaptive classification of geometric features that yields a robust algorithm for generating medial representations at different levels of abstraction. The recently introduced continuous scale axis transform serves as the mathematical foundation of our algorithm. We show how geometric and topological properties of the continuous setting carry over to discrete shape representations. Our method combines scaling operations of medial balls for geometric simplification with filtrations of the medial axis and provably good conversion steps to and from union of balls, to enable efficient processing of a wide variety shape representations including polygon meshes, 3D images, implicit surfaces, and point clouds. We demonstrate the robustness and versatility of our algorithm with an extensive validation on hundreds of shapes including complex geometries consisting of millions of triangles. © 2010 ACM.

Bernuzzi S.,Friedrich - Schiller University of Jena | Nagar A.,Institute des Hautes etudes Scientifiques | Zenginoglu A.,California Institute of Technology
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2011

We compute and analyze the gravitational waveform emitted to future null infinity by a system of two black holes in the large-mass-ratio limit. We consider the transition from the quasiadiabatic inspiral to plunge, merger, and ringdown. The relative dynamics is driven by a leading order in the mass ratio, 5PN-resummed, effective-one-body (EOB), analytic-radiation reaction. To compute the waveforms, we solve the Regge-Wheeler-Zerilli equations in the time-domain on a spacelike foliation, which coincides with the standard Schwarzschild foliation in the region including the motion of the small black hole, and is globally hyperboloidal, allowing us to include future null infinity in the computational domain by compactification. This method is called the hyperboloidal layer method, and is discussed here for the first time in a study of the gravitational radiation emitted by black hole binaries. We consider binaries characterized by five mass ratios, ν=10-2 ,-3,-4,-5 ,-6, that are primary targets of space-based or third-generation gravitational wave detectors. We show significative phase differences between finite-radius and null-infinity waveforms. We test, in our context, the reliability of the extrapolation procedure routinely applied to numerical relativity waveforms. We present an updated calculation of the final and maximum gravitational recoil imparted to the merger remnant by the gravitational wave emission, vkickend/(cν2)=0.04474±0.00007 and vkickmax/(cν2)=0.05248±0.00008. As a self-consistency test of the method, we show an excellent fractional agreement (even during the plunge) between the 5PN EOB-resummed mechanical angular momentum loss and the gravitational wave angular momentum flux computed at null infinity. New results concerning the radiation emitted from unstable circular orbits are also presented. The high accuracy waveforms computed here could be considered for the construction of template banks or for calibrating analytic models such as the effective-one-body model. © 2011 American Physical Society.

Scherlach K.,Leibniz Institute for Natural Product Research and Infection Biology | Busch B.,Leibniz Institute for Natural Product Research and Infection Biology | Lackner G.,Leibniz Institute for Natural Product Research and Infection Biology | Paszkowski U.,University of Lausanne | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2012

Division of labor: A combination of genetic, microbial, and chemical analyses solved the riddle of the dual epoxidation in the biosynthesis of rhizoxin, the causative agent of rice seedling blight. Bacterial endosymbionts of Rhizopus microsporus mediate the first epoxidation by a dedicated cytochrome P450 monooxygenase. The second oxirane ring is introduced by the fungal host and results in a substantially increased potency of the phytotoxin. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Silbereisen R.K.,Friedrich - Schiller University of Jena
International Journal of Developmental Sciences | Year: 2012

From a biopsychosocial perspective on human development, this essay review introduces a model linking social changes at the macro level with individual development at the micro level. German unification and the globalization of economy that followed are taken as a case in point for social changes that have affected the lives of many. It is argued that social change cascades down to the individual level through various contexts of development where it is manifested in terms of demands individuals have to negotiate. Empirical examples from recent research on the process and results of this negotiation are provided. © 2012 - IOS Press and the authors. All rights reserved.

Pfannschmidt T.,Friedrich - Schiller University of Jena | Yang C.,CAS Institute of Botany
Protoplasma | Year: 2012

Plants convert light energy from the sun into chemical energy by photosynthesis. Since they are sessile, they have to deal with a wide range of conditions in their immediate environment. Many abiotic and biotic parameters exhibit considerable fluctuations which can have detrimental effects especially on the efficiency of photosynthetic light harvesting. During evolution, plants, therefore, evolved a number of acclimation processes which help them to adapt photosynthesis to such environmental changes. This includes protective mechanisms such as excess energy dissipation and processes supporting energy redistribution, e. g. state transitions or photosystem stoichiometry adjustment. Intriguingly, all these responses are triggered by photosynthesis itself via the interplay of its light reaction and the Calvin-Benson cycle with the residing environmental condition. Thus, besides its primary function in harnessing and converting light energy, photosynthesis acts as a sensing system for environmental changes that controls molecular acclimation responses which adapt the photosynthetic function to the environmental change. Important signalling parameters directly or indirectly affected by the environment are the pH gradient across the thylakoid membrane and the redox states of components of the photosynthetic electron transport chain and/or electron end acceptors coupled to it. Recent advances demonstrate that these signals control post-translational modifications of the photosynthetic protein complexes and also affect plastid and nuclear gene expression machineries as well as metabolic pathways providing a regulatory framework for an integrated response of the plant to the environment at all cellular levels. © 2012 Springer-Verlag.

Bernuzzi S.,Friedrich - Schiller University of Jena | Nagar A.,Institute des Hautes etudes Scientifiques | Zenginoglu A.,California Institute of Technology
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2011

We discuss the properties of the effective-one-body (EOB) multipolar gravitational waveform emitted by nonspinning black-hole binaries of masses μ and M in the extreme-mass-ratio limit μ/M=ν 1. We focus on the transition from quasicircular inspiral to plunge, merger, and ringdown. We compare the EOB waveform to a Regge-Wheeler-Zerilli waveform computed using the hyperboloidal layer method and extracted at null infinity. Because the EOB waveform keeps track analytically of most phase differences in the early inspiral, we do not allow for any arbitrary time or phase shift between the waveforms. The dynamics of the particle, common to both wave-generation formalisms, is driven by a leading-order O(ν) analytically resummed radiation reaction. The EOB and the Regge-Wheeler-Zerilli waveforms have an initial dephasing of about 5×10 -4rad and maintain then a remarkably accurate phase coherence during the long inspiral (∼33 orbits), accumulating only about -2×10 -3rad until the last stable orbit, i.e. Δφ/φ∼-5.95×10 -6. We obtain such accuracy without calibrating the analytically resummed EOB waveform to numerical data, which indicates the aptitude of the EOB waveform for studies concerning the Laser Interferometer Space Antenna. We then improve the behavior of the EOB waveform around merger by introducing and tuning next-to-quasicircular corrections in both the gravitational wave amplitude and phase. For each multipole we tune only four next-to-quasicircular parameters by requiring compatibility between EOB and Regge-Wheeler-Zerilli waveforms at the light ring. The resulting phase difference around the merger time is as small as ±0.015rad, with a fractional amplitude agreement of 2.5%. This suggest that next-to-quasicircular corrections to the phase can be a useful ingredient in comparisons between EOB and numerical-relativity waveforms. © 2011 American Physical Society.

Hildebrandt A.,Friedrich - Schiller University of Jena | Gray J.S.,University College Dublin | Hunfeld K.-P.,Institute of Laboratory Medicine
Infection | Year: 2013

Although best known as an animal disease, human babesiosis is attracting increasing attention as a worldwide emerging zoonosis. Humans are commonly infected by the bite of ixodid ticks. Rare ways of transmission are transplacental, perinatal and transfusion-associated. Infection of the human host can cause a very severe host-mediated pathology including fever, and hemolysis leading to anemia, hyperbilirubinuria, hemoglobinuria and possible organ failure. In recent years, apparently owing to increased medical awareness and better diagnostic methods, the number of reported cases in humans is rising steadily worldwide. Hitherto unknown zoonotic Babesia spp. are now being reported from geographic areas where babesiosis was not previously known to occur and the growing numbers of travelers and immunocompromised individuals suggest that the frequency of cases in Europe will also continue to rise. Our review is intended to provide clinicians with practical information on the clinical management of this rare, but potentially life-threatening zoonotic disease. It covers epidemiology, phylogeny, diagnostics and treatment of human babesiosis and the potential risk of transfusion-transmitted disease with a special focus on the European situation. © 2013 Springer-Verlag Berlin Heidelberg.

Brauer J.,Friedrich - Schiller University of Jena
Interaction Studies | Year: 2015

Prosocial behaviour benefits another individual and occurs voluntarily. It may have a cognitive and a motivational component. The actor who benefits a recipient - for example by solving her/his problem (1) must recognize the recipient's goal and understand how to fulfil it and (2) has to be motivated to support the recipient. In the current paper I will review recent studies on prosocial behavior in dogs and I will compare them to studies with primates. I will address the cognitive and motivational skills required for the actor in order to support the recipient. I conclude that dogs and also chimpanzees display a number of prosocial behaviours, but there are remarkable differences. In contrast to humans, which have an outstanding biological predisposition to benefit others, dogs and chimpanzees only do so under certain conditions. © John Benjamins Publishing Company.

Reese G.,Friedrich - Schiller University of Jena | Kohlmann F.,Ludwig Maximilians University of Munich
Journal of Social Psychology | Year: 2015

Global identification has become a popular construct in recent psychological debate as it relates to harmonious intergroup relations and a caring for all humanity. Based on social identity theorizing, the current research tests whether global identification can also predict consumer choices, at the expense of lower personal benefit. Importantly, we assumed that concerns about global injustice represent a crucial component of that relation. We predicted that participants who identified strongly with all humanity would rather choose a Fairtrade product alternative over a conventional one, compared with low identifiers. In addition, we assumed that this effect be mediated by perceived global injustice. Both predictions were confirmed in a consumer choice study (N = 68). Overall, global identification and globally relevant consumer behavior seem meaningfully interconnected, and we discuss these findings with regard to recent theoretical developments in Fairtrade consumption research. © 2015 Taylor and Francis Group, LLC.

Guthmuller J.,Friedrich - Schiller University of Jena
Journal of Chemical Theory and Computation | Year: 2011

The resonance Raman (RR) intensities of o-nitrophenol (oNP) were investigated theoretically with the aim of assessing the accuracy of excited state gradients calculated with DFT and CC2 approaches. It is found that the B3LYP and B2PLYP exchange-correlation (XC) functionals provide the best estimate of the ground state properties, while the other considered approaches present significantly less accurate vibrational frequencies and normal coordinates. Then, it is demonstrated that the use of the B3LYP force field for the ground state properties, in association with XC functionals including a large amount of HF exchange (M06-2X) or including long-range corrections (CAM-B3LYP and ωB97X) for the excited state gradient calculations, provides the most accurate RR spectra. Moreover, it is found that the RR intensities calculated with the best XC functionals show comparable accuracy to the results obtained with CC2 calculations. Finally, it is seen that the accuracy of the excited state gradients does not correlate with the accuracy of the excitation energies and oscillator strengths, for which XC functionals with a lesser amount of HF exchange (B3LYP, M06, and HSE06) provide more accurate results in the case of oNP. This indicates that the assessment of excited state gradients via the calculation of RR intensities, can provide additional information about the performance of quantum chemistry approaches in predicting excited state properties. © 2011 American Chemical Society.

Navabpour P.,Friedrich - Schiller University of Jena | Barrier E.,French National Center for Scientific Research
Tectonophysics | Year: 2012

The present-day Zagros fold-and-thrust belt of SW-Iran corresponds to the former Arabian passive continental margin of the southern Neo-Tethyan basin since the Permian-Triassic rifting, undergoing later collisional deformation in mid-late Cenozoic times. In this paper an overview of brittle tectonics and palaeostress reconstructions of the Zagros fold-and-thrust belt is presented, based on direct stress tensor inversion of fault slip data. The results indicate that, during the Neo-Tethyan oceanic opening, an extensional tectonic regime affectedthe sedimentary cover in Triassic-Jurassic times with an approximately N-S trend of the σ3 axis, oblique to the margin, which was followed by some local changes to a NE-SW trend during Jurassic-Cretaceous times. The stress state significantly changed to thrust setting, with a NE-SW trend of the σ1 axis, and a compressional tectonic regime prevailed during the continental collision and folding of the sedimentary cover in Oligocene-Miocene times. This compression was then followed by a strike-slip stress state with an approximately N-S trend of the σ1 axis, oblique to the belt, during inversion of the inherited extensional basement structures in Pliocene-Recent times. The brittle tectonic reconstructions, therefore, highlighted major changes of the stress state in conjunction with transitions between thin- and thick-skinned structures during different extensional and compressional stages of continental deformation within the oblique divergent and convergent settings, respectively. © 2012 Elsevier B.V.

Sheppard C.J.R.,Italian Institute of Technology | Mehta S.B.,National Oceanic and Atmospheric Administration | Heintzmann R.,Institute of Photonic Technology | Heintzmann R.,Friedrich - Schiller University of Jena | Heintzmann R.,Kings College London
Optics Letters | Year: 2013

The effect of detector array size on resolution and signal collection efficiency of image scanning microscopy based on pixel reassignment is studied. It is shown how the method can also be employed if there is a Stokes shift in fluorescence emission wavelength. With no Stokes shift, the width of the point spread function can be sharpened by a factor of 1.53, and its peak intensity increased by a factor of 1.84. © 2013 Optical Society of America.

Behnken S.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Friedrich - Schiller University of Jena
PLoS ONE | Year: 2012

Modular type I polyketide synthases (PKS) produce a vast array of bacterial metabolites with highly diverse biological functions. Notably, all known polyketides were isolated from aerobic bacteria, and yet no example has been reported for strict anaerobes. In this study we explored the diversity and distribution of PKS genes in the genus Clostridium. In addition to comparative genomic analyses combined with predictions of modular type I polyketide synthase (PKS) gene clusters in sequenced genomes of Clostridium spp., a representative selection of other species inhabiting a variety of ecological niches was investigated by PCR screening for PKS genes. Our data reveal that all studied pathogenic Clostridium spp. are devoid of putative PKS genes. In stark contrast, cryptic PKS genes are widespread in genomes of non-pathogenic Clostridium species. According to phylogenetic analyses, the Clostridium PKS genes have unusual and diverse origins. However, reverse transcription quantitative PCR demonstrates that these genes are silent under standard cultivation conditions, explaining why the related metabolites have been overlooked until now. This study presents clostridia as a putative source for novel bioactive polyketides. © 2012 Behnken, Hertweck.

Sommerfeld J.,Friedrich - Schiller University of Jena
Biointerphases | Year: 2012

We synthesized nano-scaled periodic ripple patterns on silicon and titanium dioxide (TiO(2)) surfaces by xenon ion irradiation, and performed adsorption experiments with human plasma fibrinogen (HPF) on such surfaces as a function of the ripple wavelength. Atomic force microscopy showed the adsorption of HPF in mostly globular conformation on crystalline and amorphous flat Si surfaces as well as on nano-structured Si with long ripple wavelengths. For short ripple wavelengths the proteins seem to adsorb in a stretched formation and align across or along the ripples. In contrast to that, the proteins adsorb in a globular assembly on flat and long-wavelength rippled TiO(2), but no adsorbed proteins could be observed on TiO(2) with short ripple wavelengths due to a decrease of the adsorption energy caused by surface curvature. Consequently, the adsorption behavior of HPF can be tuned on biomedically interesting materials by introducing a nano-sized morphology while not modifying the stoichiometry/chemistry.

Williams J.T.,Oregon Health And Science University | Ingram S.L.,Oregon Health And Science University | Henderson G.,University of Bristol | Chavkin C.,University of Washington | And 6 more authors.
Pharmacological Reviews | Year: 2013

Morphine and related m-opioid receptor (MOR) agonists remain among the most effective drugs known for acute relief of severe pain. A major problem in treating painful conditions is that tolerance limits the long-term utility of opioid agonists. Considerable effort has been expended on developing an understanding of the molecular and cellular processes that underlie acute MOR signaling, short-term receptor regulation, and the progression of events that lead to tolerance for different MOR agonists. Although great progress has been made in the past decade, many points of contention and controversy cloud the realization of this progress. This review attempts to clarify some confusion by clearly defining terms, such as desensitization and tolerance, and addressing optimal pharmacological analyses for discerning relative importance of these cellular mechanisms. Cellular and molecular mechanisms regulatingMORfunction by phosphorylation relative to receptor desensitization and endocytosis are comprehensively reviewed, with an emphasis on agonistbiased regulation and areas where knowledge is lacking or controversial. The implications of these mechanisms for understanding the substantial contribution of MOR signaling to opioid tolerance are then considered in detail. While some functional MOR regulatory mechanisms contributing to tolerance are clearly understood, there are large gaps in understanding the molecular processes responsible for loss of MOR function after chronic exposure to opioids. Further elucidation of the cellular mechanisms that are regulated by opioids will be necessary for the successful development of MORbased approaches to new pain therapeutics that limit the development of tolerance. © 2013 by The American Society for Pharmacology and Experimental Therapeutics.

Lackner G.,Leibniz Institute for Natural Product Research and Infection Biology | Moebius N.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Friedrich - Schiller University of Jena
ISME Journal | Year: 2011

Burkholderia rhizoxinica and Rhizopus microsporus form a unique symbiosis in which intracellular bacteria produce the virulence factor of the phytopathogenic fungus. Notably, the host strictly requires endobacteria to sporulate. In this study, we show that the endofungal bacteria possess a type III secretion system (T3SS), which has a crucial role in the maintenance of the alliance. Mutants defective in type III secretion show reduced intracellular survival and fail to elicit sporulation of the host. Furthermore, genes coding for T3SS components are upregulated during cocultivation of the bacterial symbiont with their host. This is the first report on a T3SS involved in bacterial-fungal symbiosis. Phylogenetic analysis revealed that the T3SS represents a prototype of a clade of yet uncharacterized T3SSs within the hrp superfamily of T3SSs from plant pathogenic microorganisms. In a control experiment, we demonstrate that under laboratory conditions, rhizoxin production was not required for establishment of the symbiotic interaction. © 2011 International Society for Microbial Ecology All rights reserved.

Getzin S.,University of Gottingen | Wiegand K.,University of Gottingen | Schoning I.,Friedrich - Schiller University of Jena
Methods in Ecology and Evolution | Year: 2012

1. Structural diversity and niche differences within habitats are important for stabilizing species coexistence. However, land-use change leading to environmental homogenization is a major cause for the dramatic decline of biodiversity under global change. The difficulty in assessing large-scale biodiversity losses urgently requires new technological advances to evaluate land-use impact on diversity timely and efficiently across space. 2. While cost-effective aerial images have been suggested for potential biodiversity assessments in forests, correlation of canopy object variables such as gaps with plant or animal diversity has so far not been demonstrated using these images. 3. Here, we show that aerial images of canopy gaps can be used to assess floristic biodiversity of the forest understorey. This approach is made possible because we employed cutting-edge unmanned aerial vehicles and very high-resolution images (7cmpixel -1) of the canopy properties. We demonstrate that detailed, spatially implicit information on gap shape metrics is sufficient to reveal strong dependency between disturbance patterns and plant diversity (R 2 up to 0·74). This is feasible because opposing disturbance patterns such as aggregated and dispersed tree retention directly correspond to different functional and dispersal traits of species and ultimately to different species diversities. 4. Our findings can be used as a coarse-filter approach to conservation in forests wherever light strongly limits regeneration and biodiversity. © 2011 The Authors. Methods in Ecology and Evolution © 2011 British Ecological Society.

Janssen L.,Simon Fraser University | Janssen L.,Friedrich - Schiller University of Jena | Herbut I.F.,Simon Fraser University | Herbut I.F.,Max Planck Institute For Physik Komplexer Systeme
Physical Review B - Condensed Matter and Materials Physics | Year: 2014

Electrons on the half-filled honeycomb lattice are expected to undergo a direct continuous transition from the semimetallic into the antiferromagnetic insulating phase with increase of onsite Hubbard repulsion. We attempt to further quantify the critical behavior at this quantum phase transition by means of functional renormalization group (RG), within an effective Gross-Neveu-Yukawa theory for an SO(3) order parameter ("chiral Heisenberg universality class"). Our calculation yields an estimate of the critical exponents ν≃1.31, ηφ≃1.01, and ηΨ≃0.08, in reasonable agreement with the second-order expansion around the upper critical dimension. To test the validity of the present method, we use the conventional Gross-Neveu-Yukawa theory with Z2 order parameter ("chiral Ising universality class") as a benchmark system. We explicitly show that our functional RG approximation in the sharp-cutoff scheme becomes one-loop exact both near the upper as well as the lower critical dimension. Directly in 2+1 dimensions, our chiral Ising results agree with the best available predictions from other methods within the single-digit percent range for ν and ηφ and the double-digit percent range for ηΨ. While one would expect a similar performance of our approximation in the chiral Heisenberg universality class, discrepancies with the results of other calculations here are more significant. Discussion and summary of various approaches is presented. © 2014 American Physical Society.

Poeplau C.,Johann Heinrich Von Thunen Institute | Don A.,Johann Heinrich Von Thunen Institute | Vesterdal L.,Forest and Landscape Denmark | Leifeld J.,ART Agroscope Reckenholz Tanikon | And 3 more authors.
Global Change Biology | Year: 2011

Land-use change (LUC) is a major driving factor for the balance of soil organic carbon (SOC) stocks and the global carbon cycle. The temporal dynamic of SOC after LUC is especially important in temperate systems with a long reaction time. On the basis of 95 compiled studies covering 322 sites in the temperate zone, carbon response functions (CRFs) were derived to model the temporal dynamic of SOC after five different LUC types (mean soil depth of 30±6cm). Grassland establishment caused a long lasting carbon sink with a relative stock change of 128±23% and afforestation on former cropland a sink of 116±54%, 100 years after LUC (mean±95% confidence interval). No new equilibrium was reached within 120 years. In contrast, there was no SOC sink following afforestation of grasslands and 75% of all observations showed SOC losses, even after 100 years. Only in the forest floor, there was carbon accumulation of 0.38±0.04Mgha-1yr-1 in afforestations adding up to 38±4Mgha-1 labile carbon after 100 years. Carbon loss after deforestation (-32±20%) and grassland conversion to cropland (-36±5%), was rapid with a new SOC equilibrium being reached after 23 and 17 years, respectively. The change rate of SOC increased with temperature and precipitation but decreased with soil depth and clay content. Subsoil SOC changes followed the trend of the topsoil SOC changes but were smaller (25±5% of the total SOC changes) and with a high uncertainty due to a limited number of datasets. As a simple and robust model approach, the developed CRFs provide an easily applicable tool to estimate SOC stock changes after LUC to improve greenhouse gas reporting in the framework of UNFCCC. © 2011 Blackwell Publishing Ltd.

Reese G.,Friedrich - Schiller University of Jena
Climatic Change | Year: 2016

With the 2015 summit on global climate change in Paris, political action will (or will not) be taken to tackle the threats of the global climate crisis. Both social scientists as well as conservationists have come to the conclusion that human activity is one of the main reasons for climate change and nature degradation, and the main target of justice related mitigation and adaptation responses. This article puts human (in)activity into focus, and introduces a social identity perspective on environmental justice. Specifically, it shows how conservation scientists can draw from the idea of a common human identity (CHI). It delineates how the representation of a “common human ingroup” could inform beliefs about environmental justice, which in turn should motivate individuals and groups to act in favor of the natural environment. The review highlights that social identification with all humans may represent a potential path to global environmental justice, and combines recent insights from social identity research with conservation behavior. © 2015, Springer Science+Business Media Dordrecht.

Katharina P.,Friedrich - Schiller University of Jena
Cancers | Year: 2011

In spite of optimal local control in breast cancer, distant metastases can develop as a systemic part of this disease. Surgery is suspected to contribute to metastasis formation activating dormant tumor cells. Here we add data that seeding of cells during surgery may add to the risk of metastasis formation. The change in circulating epithelial tumor cells (CETC) was monitored in 66 breast cancer patients operated on with breast conserving surgery or mastectomy and during the further course of the disease, analyzing CETC from unse parated white blood cells stained with FITC-anti-Ep CAM. An increase in cell numbers lasting until the start of chemotherapy was observed in about one third of patients. It was more preeminent in patients with low numbers of CETC before surgery and, surprisingly, in patients without involved lymph nodes. Patients with the previously reported behavior-Reincrease in cell numbers during adjuvant chemotherapy and subsequent further increase during maintenance therapy-were at increased risk of relapse. In addition to tumor cells already released during growth of the tumor, cell seeding during surgery may contribute to the early peak of relapses observed after removal of the primary tumor and chemotherapy may only marginally postpone relapse in patients with aggressively growing tumors. © 2011 by the authors; licensee MDPI, Basel, Switzerland.

Schwarzmaier C.,University of Regensburg | Sierka M.,Friedrich - Schiller University of Jena | Scheer M.,University of Regensburg
Angewandte Chemie - International Edition | Year: 2013

Extremely light sensitive yellow arsenic (As4) reacts with a weakly coordinated silver cation to afford [Ag(η2-As 4)2]+ [Al{OC(CF3)3} 4]- as the first known homoleptic arsenic complex. DFT calculations and Raman spectroscopy clearly indicate the coordination of two intact As4 tetrahedra. This unprecedented complex is used as an As4 transfer agent, which is demonstrated by the synthesis of [(PPh3)Au(η2-As4)] +[Al{OC(CF3)3}4]-. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Boysen N.,Friedrich - Schiller University of Jena
Computers and Operations Research | Year: 2010

Handling freight at cross docking terminals constitutes a complex planning task which comprises several executive steps as shipments delivered by inbound trucks are to be unloaded, sorted according to their designated destinations, moved across the dock and finally loaded onto outbound trucks for an immediate delivery elsewhere in the distribution system. To enable an efficient synchronization of inbound and outbound flows, a careful planning of operations, e.g. by computerized scheduling procedures, becomes indispensable. This work treats a special truck scheduling problem arising in the (zero-inventory) cross docks of the food industry, where strict cooling requirements forbid an intermediate storage inside the terminal, so that all products are to be instantaneously loaded onto refrigerated outbound trucks. The problem is formalized such that different operational objectives, i.e. the flow time, processing time and tardiness of outbound trucks, are minimized. To solve the resulting truck scheduling problem suited exact and heuristic solution procedures are presented. © 2009 Elsevier Ltd. All rights reserved.

Extermann M.,University of South Florida | Wedding U.,Friedrich - Schiller University of Jena
Journal of Geriatric Oncology | Year: 2012

The majority of hematologic malignancies occur in patients aged more than 65. years. Such patients have very variable health status, comorbidity levels, and geriatric syndrome prevalence. It is important to identify who would be a candidate for standard treatment schemes, and who would be a candidate for modified therapeutic approaches. Accurate assessment of patient fitness and comorbidities is key when planning therapy for this group as such factors will affect prognosis. In this paper, we review the published literature on a comprehensive geriatric assessment and comorbidity measurements in patients with hematologic malignancies and their correlation with outcomes. Our review identified the Charlson score and the Cumulative Illness Rating Scale-Geriatric as the most frequently used comorbidity instruments in the general setting, and the Hematopoietic Cell Transplantation-Comorbidity Index in the transplant setting. For the geriatric assessments, the most commonly used scheme combines age, comorbidity, Activities of Daily Living, and the presence of geriatric syndromes. Correlations with overall survival and treatment tolerance are fairly consistently demonstrated. Some tentative thresholds are apparent but remain to be firmly confirmed. Future trials should integrate these assessments as correlates or stratification tools in order to build on the early results already available. © 2011 Elsevier Inc.

Brand P.,Leibniz Institute for Age Research | Lenser T.,Friedrich - Schiller University of Jena | Hemmerich P.,Leibniz Institute for Age Research
PMC Biophysics | Year: 2010

The mammalian cell nucleus contains a variety of organelles or nuclear bodies which contribute to key nuclear functions. Promyelocytic leukemia nuclear bodies (PML NBs) are involved in the regulation of apoptosis, antiviral responses, the DNA damage response and chromatin structure, but their precise biochemical function in these nuclear pathways is unknown. One strategy to tackle this problem is to assess the biophysical properties of the component parts of these macromolecular assemblies in living cells. In this study we determined PML NB assembly dynamics by live cell imaging, combined with mathematical modeling. For the first time, dynamics of PML body formation were measured in cells lacking endogenous PML. We show that all six human nuclear PML isoforms are able to form nuclear bodies in PML negative cells. All isoforms exhibit individual exchange rates at NBs in PML positive cells but PML I, II, III and IV are static at nuclear bodies in PML negative cells, suggesting that these isoforms require additional protein partners for efficient exchange. PML V turns over at PML Nbs very slowly supporting the idea of a structural function for this isoform. We also demonstrate that SUMOylation of PML at Lysine positions K160 and/or K490 are required for nuclear body formation in vivo.We propose a model in which the isoform specific residence times of PML provide both, structural stability to function as a scaffold and flexibility to attract specific nuclear proteins for efficient biochemical reactions at the surface of nuclear bodies. © 2010 Brand et al.

Wicker K.,Friedrich - Schiller University of Jena | Wicker K.,Institute of Photonic Technology
Optics Express | Year: 2013

The artefact-free reconstruction of structured illumination microscopy images requires precise knowledge of the pattern phases in the raw images. If this parameter cannot be controlled precisely enough in an experimental setup, the phases have to be determined a posteriori from the acquired data. While an iterative optimisation based on cross-correlations between individual Fourier images yields accurate results, it is rather timeconsuming. Here I present a fast non-iterative technique which determines each pattern phase from an auto-correlation of the respective Fourier image. In addition to improving the speed of the reconstruction, simulations show that this method is also more robust, yielding errors of typically less than ? /500 under realistic signal-to-noise levels. © 2013 Optical Society of America.

Wendler E.,Friedrich - Schiller University of Jena
AIP Conference Proceedings | Year: 2011

The experimental set-up at the ion beam facility in Jena allows the performance of Rutherford backscattering pectrometry (RBS) in channeling configuration at any temperature between 15 K and room temperature without changing the environment or the temperature of the sample. Doing RBS channeling studies at 15 K increases the ensitivity to defects, because the influence of lattice ibrations is reduced. Thus, the very early processes of ion induced amage formation can be studied and the cross section of damage formation per ion in virgin material, P, can be determined. At 15 K ion-beam induced damage formation itself can be investigated, because the occurrence of thermal effects can be widely excluded. In AlAs, GaN, and ZnO the cross section P measured at 15 K can be used to estimate the displacement energy for the heavier component, which is in reasonable agreement with other experiments or theoretical alculations. For a given ion species (here Ar ions) the measured cross section P exhibits a quadratic dependence P∞psrim2h PSRIM being the value calculated with SRIM using established displacement energies from other sources. From these results the displacement energy of AlN can be estimated to about 40 eV. Applying the computer code DICADA to calculate the depth distribution of displaced lattice atoms from the channeling spectra, indirect information bout the type of defects produced during ion implantation at 15 K can be obtained. In some materials like GaN or ZnO he results indicate the formation of extended defects most probably dislocation loops and thus suggest an athermal mobility of defect at 15 K. © 2011 American Institute of Physics.

Lukes-Gerakopoulos G.,Friedrich - Schiller University of Jena | Seyrich J.,University of Tubingen | Kunst D.,University of Bremen
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2014

In this paper we report the results of a thorough numerical study of the motion of spinning particles in Kerr spacetime with different prescriptions. We first evaluate the Mathisson-Papapetrou equations with two different spin supplementary conditions, namely, the Tulczyjew and the Newton-Wigner, and make a comparison of these two cases. We then use the Hamiltonian formalism given by Barausse, Racine, and Buonanno [Phys. Rev. D 80, 104025 (2009)] to evolve the orbits and compare them with the corresponding orbits provided by the Mathisson-Papapetrou equations. We include a full description of how to treat the issues arising in the numerical implementation. © 2014 American Physical Society.

Eisenhauer N.,TU Munich | Eisenhauer N.,Friedrich - Schiller University of Jena | Schulz W.,University of Gottingen | Scheu S.,University of Gottingen | Jousset A.,University of Gottingen
Functional Ecology | Year: 2013

Biodiversity is a central factor driving community invasibility. Diverse communities exploit resources more efficiently, leaving less free niche space available to invaders. Niche partitioning, however, is only possible in complex resource environments, and we hypothesized that resource richness drives the biodiversity-invasibility relationship. We tested the effect of two biodiversity indices, taxonomic richness and functional dissimilarity, on the invasibility of Pseudomonas fluorescens communities in microcosms of varying resource richness, herein used as a proxy for niche dimensionality, because different P. fluorescens genotypes differed in their ability to use those resources. Invader success was negatively correlated with the diversity of the resident community, with functional dissimilarity being of greater significance than taxonomic richness. Varied niche dimensionality revealed different mechanisms determining community invasibility: at low niche dimensionality, invasibility was driven by the presence of particular genotypes (identity effect) rather than by the biodiversity of the resident community. At high niche dimensionality, functional dissimilarity increased community productivity and reduced invasion, most likely through complementarity effects. The results show that functionally dissimilar bacterial strains efficiently exploit their environment, reducing the resources available for invasive species. These findings call for the preservation of functionally dissimilar taxa to warrant resistance of communities against invasive species, in particular, in environments of high niche dimensionality. © 2012 The Authors. Functional Ecology © 2012 British Ecological Society.

Kilbourne B.M.,Friedrich - Schiller University of Jena
Biological Journal of the Linnean Society | Year: 2013

Scale effects on whole limb morphology (i.e. bones together with in situ overlying muscles) are well understood for the neognath forelimb. However, scale effects on neognath gross hindlimb morphology remain largely unexplored. To broaden our understanding of avian whole limb morphology, I investigated the scaling of hindlimb inertial properties in neognath birds, testing empirical scaling relationships against the model of geometric similarity. Inertial property data - mass, moment of inertia, centre of mass distance, and radius of gyration - were collected from 22 neognath species representing a wide range of locomotor specializations. When scaled against body mass, hindlimb inertial properties scale with positive allometry. Thus, in terms of morphology, larger bodied neognaths possess hindlimbs requiring disproportionately more energy to accelerate and decelerate relative to body mass than smaller bodied birds. When scaled against limb length, hindlimb inertial properties scale according to isometry. In the subclade Land Birds (sensuHackett etal.), hindlimb inertial properties largely scale according to positive allometry. The contrasting results of positive allometry vs. isometry in neognaths are due to how hindlimb length scales against body mass. Negative allometry of hindlimb inertial properties, which would reduce terrestrial locomotion costs, would probably make the hindlimb susceptible to mechanical failure or too diminutive for its many ecological functions. Comparing the scaling relationships of wings and hindlimbs highlights how locomotor costs influence the scaling of limb inertial properties. © 2013 The Linnean Society of London.

Gramss G.,Friedrich - Schiller University of Jena | Voigt K.-D.,Food GmbH Jena
Plant and Soil | Year: 2013

Aims: Along a gradient of diminishing heavy metal (HM) concentrations formed by local inclusions of uranium mine soils into non-contaminated cropland, duplicate 1-m2 plots of 3 winter wheat cvs. (Akteur E, Brilliant A, and Bussard E) were established at 3 positions within a winter rye (cv. Visello) culture. It was the goal to determine permissible soil HM concentrations tolerated by cereal cvs. with variable excluder properties, and regulatory mechanisms which optimize the concentrations of essential minerals and radionuclide analogues in viable seeds from geologically related soils with diverging HM content. Methods: Total metal concentrations / nitrogen species in soils, shoots, and mature grains were determined by ICP-MS / spectrophotometry, and Kjeldahl analyses. Results: No non-permissible concentrations in grains of the 4 cereal cvs. were caused by elevated but aged total soil resources (mg kg-1 DW) in As (156); Cu (283); Mn (2,130); Pb (150); and in Zn (3,005) in the case of Bussard although CdCuZn elicited phytotoxicity symptoms. Uranium (41) contaminated grains of Akteur and Brilliant but not of Bussard and Visello due to their excluder properties. The concentration in Cd (41) had to be reduced to 20/2 mg kg-1 for the production by excluder cvs. of fodder/food grains. Cultivars excluding both HM and radionuclide analogues such as BaCsSr synchronously were not identified. Whereas plant tissue concentrations in the metalloprotein-associated elements CdCoCuMnNiZn rise and fall generally with Norg, grains of the wheat cvs. differed too little in Norg to designate variations in their metal acquisition rates solely as protein-regulated. Wheat grains confined nevertheless the concentrations in Cu to 11-14 mg kg-1 although the respective soil concentrations varied by factor 19. Grain deposition in CaFeMn(Zn) and in nuclides followed the same rules. Conclusions: It is hypothesized that cereals down-/up-regulate grain:soil transfer rates from soils with excessive/deficient trace metal resources to equip viable seeds with an optimum but not maximum in essential minerals. Positive correlations between metal concentrations in planta to those in soil can thereby be lost. © 2012 Springer Science+Business Media B.V.

Malghani S.,Max Planck Institute for Biogeochemistry | Malghani S.,Friedrich - Schiller University of Jena | Gleixner G.,Max Planck Institute for Biogeochemistry | Trumbore S.E.,Max Planck Institute for Biogeochemistry
Soil Biology and Biochemistry | Year: 2013

Bio-char, biomass that has been deliberately charred to slow its rate of decomposition, has been proposed as an amendment with the potential to sequester carbon and improve certain soil properties. Slow pyrolysis (temperature ≤500°C) and hydrothermal carbonization (low temperature, high pressure) are two efficient methods to produce bio-char with high yield and are applicable to a broad range of feedstocks. Chars made using slow pyrolysis (PC) and hydrothermal carbonization (HTC) of the same feedstock material (corn, C4) differed in physical appearance, chemical properties and decomposition behavior. We added these HTC and PC chars as amendments to three soils with C3-derived organic matter that differed in clay content, pH, and land use (managed spruce forest, unmanaged deciduous forest and agriculture), and compared their impacts on carbon sequestration and net greenhouse gas (CO2, 13CO2, N2O and CH4) emissions. HTC addition (1% w/w) significantly increased CO2 emissions in all three soils (p<0.001), with much of the extra C derived from HTC decomposition. In contrast, PC addition (1% w/w) had almost no impact on deciduous forest soil and actually decreased CO2 emission from the agricultural soil. HTC treatment resulted in increased CH4 emission from all soils but reduced N2O fluxes in the agricultural and spruce forest soils. PC amendment had no significant effect on CH4 emission, and resulted in intermediate levels of N2O emission (between control and HTC treatments). Although both HTC and PC chars were produced from the same feedstock, PC had markedly higher potential for carbon sequestration than HTC. © 2013 Elsevier Ltd.

Ibrahim B.,Friedrich - Schiller University of Jena | Ibrahim B.,University of Umm Al - Qura | Ibrahim B.,Al Qunfudah Center for Scientific Research
Progress in Biophysics and Molecular Biology | Year: 2015

Reproduction and natural selection are the key elements of life. In order to reproduce, the genetic material must be doubled, separated and placed into two new daughter cells, each containing a complete set of chromosomes and organelles. In mitosis, transition from one process to the next is guided by intricate surveillance mechanisms, known as the mitotic checkpoints. Dis-regulation of cell division through checkpoint malfunction can lead to developmental defects and contribute to the development or progression of tumors.This review approaches two important mitotic checkpoints, the spindle assembly checkpoint (SAC) and the spindle position checkpoint (SPOC). The highly conserved spindle assembly checkpoint (SAC) controls the onset of anaphase by preventing premature segregation of the sister chromatids of the duplicated genome, to the spindle poles. In contrast, the spindle position checkpoint (SPOC), in the budding yeast Saccharomyces cerevisiae, ensures that during asymmetric cell division mitotic exit does not occur until the spindle is properly aligned with the cell polarity axis. Although there are no known homologs, there is indication that functionally similar checkpoints exist also in animal cells. This review can be regarded as an "executable model", which could be easily translated into various quantitative concrete models like Petri nets, ODEs, PDEs, or stochastic particle simulations. It can also function as a base for developing quantitative models explaining the interplay of the various components and proteins controlling mitosis. © 2015 Elsevier Ltd.

Franke J.,Leibniz Institute for Natural Product Research and Infection Biology | Ishida K.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Friedrich - Schiller University of Jena
Angewandte Chemie - International Edition | Year: 2012

Biosynthetic secrets unveiled: Targeted promoter exchange in a cryptic biosynthesis gene cluster conserved among certain pathogenic Burkholderia species yielded a highly unstable, structurally unprecedented polyketide, burkholderic acid (1). Labeling experiments, gene knock-outs, and bioinformatics analyses grant first insights into a fascinating polyketide pathway. BurA is an unusual nonribosomal peptide synthetase/polyketide synthase featuring internal thioesterase domains. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hanisch A.,University of Bayreuth | Groschel A.H.,University of Bayreuth | Fortsch M.,University of Bayreuth | Drechsler M.,University of Bayreuth | And 4 more authors.
ACS Nano | Year: 2013

Directed self-assembly processes of polymeric systems represent a powerful approach for the generation of structural hierarchy in analogy to biological systems. Herein, we utilize triiodide as a strongly polarizable counterion to induce hierarchical self-assembly of an ABC miktoarm star terpolymer comprising a polybutadiene (PB), a poly(tert-butyl methacrylate) (PtBMA), and a poly(N-methyl-2-vinylpyridinium) (P2VPq) segment. Hereby, the miktoarm architecture in conjunction with an increasing ratio of triiodide versus iodide counterions allows for a stepwise assembly of spherical micelles as initial building blocks into cylindrical structures and superstructures thereof. Finally, micrometer-sized multicompartment particles with a periodic lamellar fine structure are observed, for which we introduce the term "woodlouse". The counterion-mediated decrease in hydrophilicity of the corona-forming P2VPq block is the underlying trigger to induce this hierarchical structure formation. All individual steps and the corresponding intermediates toward these well-defined superstructures were intensively studied by scattering and electron microscopic techniques, including transmission electron microtomography. © 2013 American Chemical Society.

Minardi S.,Friedrich - Schiller University of Jena
Monthly Notices of the Royal Astronomical Society | Year: 2012

Regular 2D lattices of evanescently coupled waveguides may provide in the near future photonic components capable of combining interferometrically and simultaneously a large number of telescopes, thus easing the imaging capabilities of optical interferometers. In this paper, the theoretical modelling of the so-called discrete beam combiners (DBCs) is described and compared to the conventional model used for photonic beam combiners for astronomical interferometry. The performance of DBCs as compared to an ideal ABCD beam combiner is discussed and applications to astronomical instrumentation are analysed. © 2012 The Author Monthly Notices of the Royal Astronomical Society © 2012 RAS.

Bar K.-J.,Friedrich - Schiller University of Jena
Frontiers in Neurology | Year: 2015

The majority of excess mortality among people with schizophrenia seems to be caused by cardiovascular complications, and in particular, coronary heart disease. In addition, the prevalence of heart failure and arrhythmias is increased in this population. Reduced efferent vagal activity, which has been consistently described in these patients and their healthy first-degree relatives, might be one important mechanism contributing to their increased cardiac mortality. A decrease in heart rate variability and complexity was often shown in unmedicated patients when compared to healthy controls. In addition, faster breathing rates, accompanied by shallow breathing, seem to influence autonomic cardiac functioning in acute unmedicated patients substantially. Moreover, low-physical fitness is a further and independent cardiac risk factor present in this patient population. Interestingly, new studies describe chronotropic incompetence during physical exercise as an important additional risk factor in patients with schizophrenia. Some studies report a correlation of the autonomic imbalance with the degree of positive symptoms (i.e., delusions) and some with the duration of disease. The main body of psychiatric research is focused on mental aspects of the disease, thereby neglecting obvious physical health needs of these patients. Here, a joint effort is needed to design interventional strategies in everyday clinical settings to improve physical health and quality of life. © 2015 Bär.

Riese S.,Friedrich - Schiller University of Jena | Seyfarth A.,TU Darmstadt
Bioinspiration and Biomimetics | Year: 2012

The spring-loaded inverted pendulum describes the planar center-of-mass dynamics of legged locomotion. This model features linear springs with constant parameters as legs. In biological systems, however, spring-like properties of limbs can change over time. Therefore, in this study, it is asked how variation of spring parameters during ground contact would affect the dynamics of the spring-mass model. Neglecting damping initially, it is found that decreasing stiffness and increasing rest length of the leg during a stance phase are required for orbitally stable hopping. With damping, stable hopping is found for a larger region of rest-length rates and stiffness rates. Here, also increasing stiffness and decreasing rest length can result in stable hopping. Within the predicted range of leg parameter variations for stable hopping, there is no need for precise parameter tuning. Since hopping gaits form a subset of the running gaits (with vanishing horizontal velocity), these results may help to improve leg design in robots and prostheses. © 2012 IOP Publishing Ltd.

Scholle S.,Robert Koch Hospital Apolda GmbH | Scholle H.C.,Friedrich - Schiller University of Jena
Sleep Medicine | Year: 2014

Objective: Age specific reference values of leg movements (LMS) and periodic leg movements (PLMS) in sleep considering their true periodicity to evaluate sleep pathologies, especially possible childhood RLS or PLMD. Methods: In a prospective first night study of 52 healthy children/adolescents divided into six age groups from 1 to 18 years, polysomnographies were conducted and scored considering AASM rules. The frequency of LMS and PLMS were evaluated for NREM, REM, total sleep time (TST), including attention to time structure (inter-leg movement intervals, time distribution during the night) and periodicity of LMS. Results: LMS and PLMS decreased with increasing age (P < 0.05). Children and adolescents older than 10 years had a PLMS index less than 5/h TST, in younger children the PLMS index was higher; 34.7% of total LMS and PLMS were accompanied by an EEG-arousal without age dependence. Periodicity index was low (median 0.2 decreasing with age to 0.1). Inter-leg movement intervals showed a decreasing incidence of shorter intervals with age. The course of LMS during the night displayed a lack of clear structure of distribution. Conclusions: To evaluate pediatric motoric sleep disturbances it is necessary to consider the age dependence of LMS/PLMS and their true periodicity. © 2014 Elsevier B.V.

Behnken S.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Friedrich - Schiller University of Jena
Applied Microbiology and Biotechnology | Year: 2012

Anaerobic bacteria are the oldest terrestrial creatures. They occur ubiquitously in soil and in the intestine of higher organisms and play a major role in human health, ecology, and industry. However, until lately no antibiotic or any other secondary metabolite has been known from anaerobes. Mining the genome sequences of Clostridium spp. has revealed a high prevalence of putative biosynthesis genes (PKS and NRPS), and only recently the first antibiotic from the anaerobic world, closthioamide, has been isolated from the cellulose degrading bacterium Clostridium cellulolyticum. The successful genetic induction of antibiotic biosynthesis in an anaerobe encourages further investigations of obligate anaerobes to tap their hidden biosynthetic potential. © 2012 Springer-Verlag.

Kotzampassi K.,Aristotle University of Thessaloniki | Giamarellos-Bourboulis E.J.,National and Kapodistrian University of Athens | Giamarellos-Bourboulis E.J.,Friedrich - Schiller University of Jena
International Journal of Antimicrobial Agents | Year: 2012

According to current definitions, probiotics are live microorganisms that, when ingested in adequate quantities, exert a health benefit to the host. The action of probiotics in the host is exerted by three mechanisms: modulation of the content of gut microbiota; maintenance of the integrity of the gut barrier and prevention of bacterial translocation; and modulation of the local immune response by the gut-associated immune system. Regarding their role for the prevention and treatment of infectious diseases, adequate evidence coming from randomised clinical trials (RCTs) is available for antibiotic-associated diarrhoea (AAD), Clostridium difficile infection (CDI), acute gastroenteritis and infectious complications following admission to the Intensive Care Unit (ICU). Existing evidence supports their role for decreasing the incidence of AAD and CDI when administered in parallel with antimicrobials. They also shorten the duration of symptoms when administered in paediatric populations with acute gastroenteritis, particularly of rotavirus aetiology. Available evidence is not sufficient to support administration for the management of CDI. Regarding populations of critically ill patients, data from many RCTs suggest a decrease of infectious complications by starting feeding with probiotics following ICU admission, with the exception of patients suffering from severe pancreatitis. However, it should be underscored that all analysed RCTs are characterised by marked heterogeneity regarding the type of administered probiotic species, precluding robust recommendations. © 2012 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

Mayer F.L.,Hans Knoell institute | Wilson D.,Hans Knoell institute | Hube B.,Hans Knoell institute | Hube B.,Universitatsklinikum | Hube B.,Friedrich - Schiller University of Jena
Virulence | Year: 2013

The polymorphic fungus Candida albicans is a member of the normal human microbiome. In most individuals, C. albicans resides as a lifelong, harmless commensal. Under certain circumstances, however, C. albicans can cause infections that range from superficial infections of the skin to life-threatening systemic infections. Several factors and activities have been identified which contribute to the pathogenic potential of this fungus. Among them are molecules which mediate adhesion to and invasion into host cells, the secretion of hydrolases, the yeast-to-hypha transition, contact sensing and thigmotropism, biofilm formation, phenotypic switching and a range of fitness attributes. Our understanding of when and how these mechanisms and factors contribute to infection has significantly increased during the last years. In addition, novel virulence mechanisms have recently been discovered. In this review we present an update on our current understanding of the pathogenicity mechanisms of this important human pathogen. © 2013 Landes Bioscience.

Richter N.,Friedrich - Schiller University of Jena | Richter N.,Helmholtz Center Potsdam | Poland M.P.,U.S. Geological Survey | Lundgren P.R.,Jet Propulsion Laboratory
Geophysical Research Letters | Year: 2013

On 19 March 2008, a small explosive eruption at the summit of Kīlauea Volcano, Hawai'i, heralded the formation of a new vent along the east wall of Halema'uma'u Crater. In the ensuing years, the vent widened due to collapses of the unstable rim and conduit wall; some collapses impacted an actively circulating lava pond and resulted in small explosive events. We used synthetic aperture radar data collected by the TerraSAR-X satellite, a joint venture between the German Aerospace Center (DLR) and EADS Astrium, to identify and analyze small-scale surface deformation around the new vent during 2008-2012. Lidar data were used to construct a digital elevation model to correct for topographic phase, allowing us to generate differential interferograms with a spatial resolution of about 3 m in Kīlauea's summit area. These interferograms reveal subsidence within about 100 m of the rim of the vent. Small baseline subset time series analysis suggests that the subsidence rate is not constant and, over time, may provide an indication of vent stability and potential for rim and wall collapse - information with obvious hazard implications. The deformation is not currently detectable by other space- or ground-based techniques. Key Points High-resolution InSAR data is used to monitor small-scale volcano deformation ©2013. American Geophysical Union. All Rights Reserved.

Das P.,DWI Leibniz Institute for Interactive Materials | Malho J.-M.,VTT Technical Research Center of Finland | Rahimi K.,DWI Leibniz Institute for Interactive Materials | Schacher F.H.,Friedrich - Schiller University of Jena | And 3 more authors.
Nature Communications | Year: 2015

Nacre-mimetics hold great promise as mechanical high-performance and functional materials. Here we demonstrate large progress of mechanical and functional properties of self-assembled polymer/nanoclay nacre-mimetics by using synthetic nanoclays with aspect ratios covering three orders in magnitude (25-3,500). We establish comprehensive relationships among structure formation, nanostructuration, deformation mechanisms and mechanical properties as a function of nanoclay aspect ratio, and by tuning the viscoelastic properties of the soft phase via hydration. Highly ordered, large-scale nacre-mimetics are obtained even for low aspect ratio nanoplatelets and show pronounced inelastic deformation with very high toughness, while those formed by ultralarge nanoplatelets exhibit superb stiffness and strength, previously only reachable for highly crosslinked materials. Regarding functionalities, we report formerly impossible glass-like transparency, and excellent gas barrier considerably exceeding earlier nacre-mimetics based on natural nanoclay. Our study enables rational design of future high-performance nacre-mimetic materials and opens avenues for ecofriendly, transparent, self-standing and strong advanced barrier materials. © 2015 Macmillan Publishers Limited. All rights reserved.

Damour T.,Institute des Hautes etudes Scientifiques | Jaranowski P.,University of Bialystok | Schafer G.,Friedrich - Schiller University of Jena
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2016

The fourth post-Newtonian (4PN) two-body dynamics has been recently tackled by several different approaches: effective field theory, Arnowitt-Deser-Misner Hamiltonian, action-angle-Delaunay averaging, effective-one-body, gravitational self-force, first law of dynamics, and Fokker action. We review the achievements of these approaches and discuss the complementarity of their results. Our main conclusions are: (i) the results of the first complete derivation of the 4PN dynamics [T. Damour, P. Jaranowski, and G. Schäfer, Phys. Rev. D 89, 064058 (2014)] have been, piecewise, fully confirmed by several subsequent works; (ii) the results of the Delaunay-averaging technique [T. Damour, P. Jaranowski, and G. Schäfer, Phys. Rev. D 91, 084024 (2015)] have been confirmed by several independent works; and (iii) several claims in a recent harmonic-coordinates Fokker-action computation [L. Bernard et al., arXiv:1512.02876v2] are incorrect, but can be corrected by the addition of a couple of ambiguity parameters linked to subtleties in the regularization of infrared and ultraviolet divergences. © 2016 American Physical Society.

Reissmann S.,Friedrich - Schiller University of Jena | Reissmann S.,Jena Bioscience GmbH
Journal of Peptide Science | Year: 2014

The penetration of polar or badly soluble compounds through a cell membrane into live cells requires mechanical support or chemical helpers. Cell-penetrating peptides (CPPs) are very promising chemical helpers. Because of their low cytotoxicity and final degradation to amino acids, they are particularly favored in in vivo studies and for clinical applications. Clearly, the future of CPP research is bright; however, the required optimization studies for each drug require considerable individualized attention. Thus, CPPs are not the philosopher's stone. As of today, a large number of such transporter peptides with very different sequences have been identified. These have different uptake mechanisms and can transport different cargos. Intracellular concentrations of cargos can reach a low micromole range and are able to influence intracellular reactions. Internalized ribonucleic acids such as small interfering RNA (siRNA) and mimics of RNA such as peptide nucleic acids, morpholino nucleic acids, and triesters of oligonucleotides can influence transcription and translation. Despite the highly efficient internalization of antibodies, enzymes, and other protein factors, as well as siRNA and RNA mimics, the uptake and stabile insertion of DNA into the genome of the host cells remain substantially challenging. This review describes a wide array of differing CPPs, cargos, cell lines, and tissues. The application of CPPs is compared with electroporation, magnetofection, lipofection, viral vectors, dendrimers, and nanoparticles, including commercially available products. The limitations of CPPs include low cell and tissue selectivity of the first generation and the necessity for formation of fusion proteins, conjugates, or noncovalent complexes to different cargos and of cargo release from intracellular vesicles. Furthermore, the noncovalent complexes require a strong molar excess of CPPs, and extensive experimentation is required to determine the most optimal CPP for any given cargo and cell type. Yet to predict which CPP is optimal for any given target remains a complex question. More recently, there have been promising developments: the enhancement of cell specificity using activatable CPPs, specific transport into cell organelles by insertion of corresponding localization sequences, and the transport of drugs through blood-brain barriers, through the conjunctiva of eyes, skin, and into nerve cells. Proteins, siRNA, and mimics of oligonucleotides can be efficiently transported into cells and have been tested for treatment of certain diseases. The recent state of the art in CPP research is discussed together with the overall scope, limitations, and some recommendations for future research directions. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.

Bocker S.,Friedrich - Schiller University of Jena | Damaschke P.,Chalmers University of Technology
Information Processing Letters | Year: 2011

Cluster Deletion and Cluster Editing ask to transform a graph by at most k edge deletions or edge edits, respectively, into a cluster graph, i.e., disjoint union of cliques. Equivalently, a cluster graph has no conflict triples, i.e., two incident edges without a transitive edge. We solve the two problems in time Oâ'Ž(1.415k) and Oâ'Ž(1.76k), respectively. These results round off our earlier work by considerably improved time bounds. For Cluster Deletion we use a technique that cuts away small connected components that do no longer contribute to the exponential part of the time complexity. As this idea is simple and versatile, it may lead to improvements for several other parameterized graph problems. The improvement for Cluster Editing is achieved by using the full power of an earlier structure theorem for graphs where no edge is in three conflict triples. © 2011 Elsevier B.V.

Eichhorn A.,Friedrich - Schiller University of Jena
Journal of Physics: Conference Series | Year: 2012

Any theory of quantum gravity must ultimately be connected to observations. This demand is difficult to be met due to the high energies at which we expect the quantum nature of gravity to become manifest. Here we study, how viable quantum gravity proposals can be restricted by investigating the interplay of gravitational and matter degrees of freedom. Specifically we demand that a valid quantum theory of gravity must allow for the existence of light (compared to the Planck scale) fermions, since we observe these in our universe. Within the effective theory framework, we can thus show that UV completions for gravity are restricted, regardless of the details of the microscopic theory. Specialising to asymptotically safe quantum gravity, we find indications that universes with light fermions are favoured within this UV completion for gravity. © Published under licence by IOP Publishing Ltd.

Huettner M.,Max Planck Institute for Biogeochemistry | Huettner M.,Friedrich - Schiller University of Jena
Environmental Science and Policy | Year: 2012

REDD+ (reducing emissions from deforestation and forest degradation and the enhancement of carbon stocks) emerges as promising incentive mechanism for tropical forest protection. While REDD+ is expected to yield poverty reduction and biodiversity co-benefits, its mechanism design options pose several risks to socio-economic compatibility and environmental integrity.We conduct a REDD+ expert survey to rate the perceived importance and likelihood of these risks to national REDD+ implementation. The dependency of the risk perception on stakeholder characteristics is analyzed using seemingly unrelated regression analysis and ANOVA. Additionally, the survey investigates the perceived effectiveness of different policy options to minimize these risks.The majority of stakeholders viewed governance challenges as the largest risks to REDD+ implementation and preferred mandatory incentive and regulatory policy measures to mitigate them. Understanding these stakeholder perceptions will not only help improving national REDD+ implementation, but also provide insights for the international policy process. © 2011 Elsevier Ltd.

Fritsch M.,Friedrich - Schiller University of Jena | Krabel S.,University of Kassel
Journal of Technology Transfer | Year: 2012

This study investigates the factors that shape the attitudes of scientists toward starting their own business or working in a private sector firm. The analysis is based on data collected from scientists working in the German Max Planck Society, a research institution devoted to basic science. We find that the scientists' attractiveness of working in a private sector firm or of starting their own business differ considerably according to their academic discipline and the self-reported commercial potential of their research. The ability to take risks, prior work experience in private firms, and personal experience in cooperating with industry lead to a positive attitude towards switching to private sector employment or entrepreneurship. Strong willingness to freely distribute research findings is related to a low appeal of private sector work. © 2010 Springer Science+Business Media, LLC.

Keller M.,Friedrich - Schiller University of Jena
Discrete and Computational Geometry | Year: 2011

We introduce a curvature function for planar graphs to study the connection between the curvature and the geometric and spectral properties of the graph. We show that non-positive curvature implies that the graph is infinite and locally similar to a tessellation. We use this to extend several results known for tessellations to general planar graphs. For non-positive curvature, we show that the graph admits no cut locus and we give a description of the boundary structure of distance balls. For negative curvature, we prove that the interiors of minimal bigons are empty and derive explicit bounds for the growth of distance balls and Cheeger's constant. The latter are used to obtain lower bounds for the bottom of the spectrum of the discrete Laplace operator. Moreover, we give a characterization for triviality of the essential spectrum by uniform decrease of the curvature. Finally, we show that non-positive curvature implies the absence of finitely supported eigenfunctions for nearest neighbor operators. © 2011 Springer Science+Business Media, LLC.

Farhat M.,Friedrich - Schiller University of Jena | Guenneau S.,Fresnel Institute | Enoch S.,Fresnel Institute
Physical Review B - Condensed Matter and Materials Physics | Year: 2012

A cylindrical cloak is designed to control the bending waves propagating in isotropic thin plates. This is achieved through homogenization of a multiply perforated coating of isotropic homogeneous elastic material, which greatly simplifies the design of the multilayered cloak we proposed. We first derive the homogenized biharmonic equation, which involves an anisotropic Young's modulus and an isotropic mass density. We then numerically show that a clamped obstacle is cloaked over a finite range of frequencies for an acoustic source located a couple of wavelengths away from its surrounding cloak. The reduced backward and forward scattering is confirmed by both the profile of the total field computed along a line passing through the source and the center of the cloak (near field confirmation), and the computation of the scattered far field. © 2012 American Physical Society.

Background: Copy number variations (CNVs) having no (obvious) clinical effects were rediscovered as major part of human genome in 2004. However, for every cytogeneticist microscopically visible harmless CNVs (CG-CNVs) are well known since decades. Harmless CG-CNVs can be present as heterochromatic or even as euchromatic variants in clinically healthy persons. Results: Here I provide a review on what is known today on the still too little studied harmless human CG-CNVs, point out which can be mixed up with clinically relevant pathological CG-CNVs and shortly discuss that the artificial separation of euchromatic submicroscopic CNVs (MG-CNVs) and euchromatic CG-CNVs is no longer timely. Conclusion: Overall, neither so-called harmless heterochromatic nor so-called harmless euchromatic CG-CNVs are considered enough in evaluation of routine cytogenetic analysis and reporting. This holds especially true when bearing in mind the so-called two-hit model suggesting that combination of per se harmless CNVs may lead to clinical aberrations if they are present together in one patient. © 2016 Liehr.

Lukes-Gerakopoulos G.,Friedrich - Schiller University of Jena
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2014

In this work, chaotic indicators, which have been established in the framework of classical mechanics, are reformulated in the framework of general relativity in such a way that they are invariant under coordinate transformation. For achieving this, the prescription for reformulating mLCE given by [Y. Sota, S. Suzuki, and K.-I. Maeda, Classical Quantum Gravity 13, 1241 (1996)] is adopted. Thus, the geodesic deviation vector approach is applied, and the proper time is utilized as the measure of time. Following the aforementioned prescription, the chaotic indicators FLI, MEGNO, GALI, and APLE are reformulated. In fact, FLI has been reformulated by adapting other prescriptions in the past, but not by adapting the Sota et al. one. By using one of these previous reformulations of FLI, an approximative expression giving MEGNO as function of FLI has been applied on nonintegrable curved spacetimes in a recent work. In the present work the reformulation of MEGNO is provided by adjusting the definition of the indicator to the Sota et al. prescription. GALI and APLE are reformulated in the framework of general relativity for the first time. All the reformulated indicators by Sota et al. prescription are tested and compared for their efficiency to discern order from chaos. © 2014 American Physical Society.

Plyushchay M.S.,University of Santiago de Chile | Wipf A.,Friedrich - Schiller University of Jena
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2014

We show that a nonrelativistic particle in a combined field of a magnetic monopole and 1/r2 potential reveals a hidden, partially free dynamics when the strength of the central potential and the charge-monopole coupling constant are mutually fitted to each other. In this case the system admits both a conserved Laplace-Runge-Lenz vector and a dynamical conformal symmetry. The supersymmetrically extended system corresponds then to a background of a self-dual or anti-self-dual dyon. It is described by a quadratically extended Lie superalgebra D(2,1;α) with α=1/2, in which the bosonic set of generators is enlarged by a generalized Laplace-Runge-Lenz vector and its dynamical integral counterpart related to Galilei symmetry, as well as by the chiral Z2-grading operator. The odd part of the nonlinear superalgebra comprises a complete set of 24=2×3×4 fermionic generators. Here a usual duplication comes from the Z2-grading structure; the second factor can be associated with a triad of scalar integrals - the Hamiltonian, the generator of special conformal transformations, and the squared total angular momentum vector, while the quadruplication is generated by a chiral spin vector integral which exits due to the (anti-)self-dual nature of the electromagnetic background. © 2014 American Physical Society.

Bruhn C.,Leibniz Institute for Age Research | Zhou Z.-W.,Leibniz Institute for Age Research | Ai H.,Leibniz Institute for Age Research | Wang Z.-Q.,Leibniz Institute for Age Research | Wang Z.-Q.,Friedrich - Schiller University of Jena
Cell Reports | Year: 2014

The MRN complex (Mre11/Rad50/Nbs1) is important in double-strand break (DSB) recognition, end resection, replication fork stabilization, and ATM and ATR activation. Complete deletion of MRN is incompatiblewith cell and organism life, presumably dueto replication-born DSBs; however, the underlying mechanism remains unknown. We devised anoninvasive high-content assay, termed high-content microscopy- assisted cell-cycle phenotyping (hiMAC), to investigate the fate of cells lacking Nbs1. Surprisingly, deletion of Nbs1 does not kill cells during replication. The primary lesions in Nbs1-deleted cells are replication intermediates that result from defective resolution rather than fork destabilization. These lesions are converted to DSBs in the subsequent G2 phase, which subsequently activate Chk1, delay G2 progression, and lead to chromosome instability. Nbs1-deleted cells establish a DSB equilibrium that permits cell cycling but activates p53, causing G1 and G2 arrest, and cell death. Thus, we identify a physiological role of Nbs1 in the resolution of stalled replication forks. © 2014 The Authors.

Demmel M.,University of Mainz | Saueressig F.,Radboud University Nijmegen | Zanusso O.,Friedrich - Schiller University of Jena
Annals of Physics | Year: 2015

We construct a novel Wetterich-type functional renormalization group equation for gravity which encodes the gravitational degrees of freedom in terms of gauge-invariant fluctuation fields. Applying a linear-geometric approximation the structure of the new flow equation is considerably simpler than the standard Quantum Einstein Gravity construction since only transverse-traceless and trace part of the metric fluctuations propagate in loops. The geometric flow reproduces the phase-diagram of the Einstein-Hilbert truncation including the non-Gaussian fixed point essential for Asymptotic Safety. Extending the analysis to the polynomial f(R)-approximation establishes that this fixed point comes with similar properties as the one found in metric Quantum Einstein Gravity; in particular it possesses three UV-relevant directions and is stable with respect to deformations of the regulator functions by endomorphisms. © 2015 Elsevier Inc.

Xu Z.,Leibniz Institute for Natural Product Research and Infection Biology | Ding L.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Friedrich - Schiller University of Jena
Angewandte Chemie - International Edition | Year: 2011

Sharing a branch: The first biosynthesis of an unprecedented branched PKS extender unit from valine/isobutyrate was unveiled, involving a designated ketosynthase III and a crotonyl reductase/carboxylase (CCR). Isobutylmalonyl-CoA (ibMCoA) is not only employed in divergolide biosynthesis but is also incorporated into novel, antibacterial germicidins (see scheme). Such natural biocombinatorics are unparalleled in polyketide biosynthesis. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hertweck C.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Friedrich - Schiller University of Jena
Angewandte Chemie - International Edition | Year: 2011

Two become one: Pyrrolysine, a critical component of several methyltransferases in archaebacteria, is the latest addition to the inventory of genetically encoded amino acids. Studies at the genetic, biochemical, and chemical levels have now revealed that this rare amino acid is assembled from two lysine units via an unusual ε-dipeptide, and is then charged by a designated translational machinery. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Niedermeier R.,Friedrich - Schiller University of Jena
Leibniz International Proceedings in Informatics, LIPIcs | Year: 2010

Research on parameterized algorithmics for NP-hard problems has steadily grown over the last years. We survey and discuss how parameterized complexity analysis naturally develops into the field of multivariate algorithmics. Correspondingly, we describe how to perform a systematic investigation and exploitation of the "parameter space" of computationally hard problems. © R. Niedermeier.

Zaslansky R.,Friedrich - Schiller University of Jena
European journal of pain (London, England) | Year: 2012

Post-operative pain exacts a high toll from patients, families, healthcare professionals and healthcare systems worldwide. PAIN-OUT is a research project funded by the European Union's 7th Framework Program designed to develop effective, evidence-based approaches to improve pain management after surgery, including creating a registry for feedback, benchmarking and decision support. In preparation for PAIN-OUT, we conducted a pilot study to evaluate the feasibility of international data collection with feedback to participating sites. Adult orthopaedic or general surgery patients consented to participate between May and October 2008 at 14 collaborating hospitals in 13 countries. Project staff collected patient-reported outcomes and process data from 688 patients and entered the data into an online database. Project staff in 10 institutions met the enrolment criteria of collecting data from at least 50 patients. The completeness and quality of the data, as assessed by rate of missing data, were acceptable; only 2% of process data and 0.06% of patient-reported outcome data were missing. Participating institutions received access to select items as Web-based feedback comparing their outcomes to those of the other sites, presented anonymously. We achieved proof of concept because staff and patients in all 14 sites cooperated well despite marked differences in cultures, nationalities and languages, and a central database management team was able to provide valuable feedback to all. © 2011 European Federation of International Association for the Study of Pain Chapters.

Ruelens P.,Catholic University of Leuven | De Maagd R.A.,Business Unit Bioscience | Proost S.,University of Potsdam | Proost S.,Max Planck Institute of Molecular Plant Physiology | And 3 more authors.
Nature Communications | Year: 2013

MADS-domain transcription factors have been shown to act as key repressors or activators of the transition to flowering and as master regulators of reproductive organ identities. Despite their important roles in plant development, the origin of several MADS-box subfamilies has remained enigmatic so far. Here we demonstrate, through a combination of genome synteny and phylogenetic reconstructions, the origin of three major, apparently angiosperm-specific MADS-box gene clades: FLOWERING LOCUS C-(FLC-), SQUAMOSA-(SQUA-) and SEPALLATA-(SEP-)-like genes. We find that these lineages derive from a single ancestral tandem duplication in a common ancestor of extant seed plants. Contrary to common belief, we show that FLC-like genes are present in cereals where they can also act as floral repressors responsive to prolonged cold or vernalization. This opens a new perspective on the translation of findings from Arabidopsis to cereal crops, in which vernalization was originally described. © 2013 Macmillan Publishers Limited. All rights reserved.

Treffer R.,Institute For Photonische Technologien Jena Ipht | Deckert V.,Institute For Photonische Technologien Jena Ipht | Deckert V.,Friedrich - Schiller University of Jena
Current Opinion in Biotechnology | Year: 2010

Recent advances in sequencing technologies exhibit a tendency towards single-molecule sequencing, which eventually will lead to the commercial implementation of such platforms. For this purpose dye labelling is currently the foundation of most approaches and an overview is provided on the latest developments. For label-free sequencing the detection of conductivity changes using nanopores or nano-edges will be discussed as well as another promising method that is based on Raman spectroscopy. Here the most recent advance aims to utilize the high lateral resolution of tip-enhanced Raman scattering. For this sequencing procedure Raman spectra must be collected along the DNA or RNA strand, while the difference spectra will provide a direct sequence reading without prior labelling. © 2010 Elsevier Ltd.

Sugimoto Y.,Leibniz Institute for Natural Product Research and Infection Biology | Ding L.,Leibniz Institute for Natural Product Research and Infection Biology | Ishida K.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Friedrich - Schiller University of Jena
Angewandte Chemie - International Edition | Year: 2014

The unusual nitro-substituted polyketides aureothin, neoaureothin (spectinabilin), and luteoreticulin, which are produced by diverse Streptomyces species, point to a joint evolution. Through rational genetic recombination and domain exchanges we have successfully reprogrammed the modular (type I) aur polyketide synthase (PKS) into a synthase that generates luteoreticulin. This is the first rational transformation of a modular PKS to produce a complex polyketide that was initially isolated from a different bacterium. A unique aspect of this synthetic biology approach is that we exclusively used genes from a single biosynthesis gene cluster to design the artificial pathway, an avenue that likely emulates natural evolutionary processes. Furthermore, an unexpected, context-dependent switch in the regiospecificity of a pyrone methyl transferase was observed. We also describe an unprecedented scenario where an AT domain iteratively loads an extender unit onto the cognate ACP and the downstream ACP. This aberrant function is a novel case of non-colinear behavior of PKS domains. Transformers: Through genetic reprogramming, the aureothin pathway was gradually morphed into an assembly line for luteoreticulin. The first rational conversion of a complex polyketide into another natural product emulates a probable evolutionary scenario. This study also reveals the unprecedented iterative use of an acyl transferase domain and a context-dependent switch in the regioselectivity of a pyrone methyltransferase. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wood B.R.,Monash University | Asghari-Khiavi M.,Monash University | Asghari-Khiavi M.,Massachusetts Institute of Technology | Bailo E.,Leibniz Institute for Analytical Sciences | And 3 more authors.
Nano Letters | Year: 2012

Hemoglobin nanocrystals were analyzed with tip-enhanced Raman scattering (TERS), surface-enhanced resonance Raman scattering (SERRS) and conventional resonance Raman scattering (RRS) using 532 nm excitation. The extremely high spatial resolution of TERS enables selective enhancement of heme, protein, and amino acid bands from the crystal surface not observed in the SERRS or RRS spectra. Two bands appearing at 1378 and 1355 cm -1 assigned to the ferric and ferrous oxidation state marker bands, respectively, were observed in both TERS and SERRS spectra but not in the RRS spectrum of the bulk sample. The results indicate that nanoscale oxidation changes are occurring at the hemoglobin crystal surface. These changes could be explained by oxygen exchange at the crystal surface and demonstrate the potential of the TERS technique to obtain structural information not possible with conventional Raman microscopy. © 2012 American Chemical Society.

Richter M.,Friedrich - Schiller University of Jena | Marquetand P.,University of Vienna | Gonzalez-Vazquez J.,Complutense University of Madrid | Sola I.,Complutense University of Madrid | Gonzalez L.,University of Vienna
Journal of Physical Chemistry Letters | Year: 2012

Ab initio molecular dynamics including nonadiabatic and spin-orbit couplings on equal footing is used to unravel the deactivation of cytosine after UV light absorption. Intersystem crossing (ISC) is found to compete directly with internal conversion in tens of femtoseconds, thus making cytosine the organic compound with the fastest triplet population calculated so far. It is found that close degeneracy between singlet and triplet states can more than compensate for very small spin-orbit couplings, leading to efficient ISC. The femtosecond nature of the ISC process highlights its importance in photochemistry and challenges the conventional view that large singlet-triplet couplings are required for an efficient population flow into triplet states. These findings are important to understand DNA photostability and the photochemistry and dynamics of organic molecules in general. © 2012 American Chemical Society.

Ilgenfritz E.-M.,Joint Institute for Nuclear Research | Maas A.,Friedrich - Schiller University of Jena
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

Yang-Mills theory and QCD are well defined for any Lie group as gauge group. The choice G2 is of great interest, as it is the smallest group with trivial center and being at the same time accessible to simulations. This theory has been found to have many properties in common with SU(3) Yang-Mills theory and QCD, permitting us to study the role of the center. Herein, these investigations are extended to topological properties of G 2 Yang-Mills theory. After giving the instanton construction for G2, topological lumps with instanton topological charge are identified in cooled lattice configurations. The corresponding topological susceptibility is determined in the vacuum and at low and high temperatures, showing a significant response to the phase structure of the theory. © 2012 American Physical Society.

Galaviz P.,Monash University | Galaviz P.,Friedrich - Schiller University of Jena
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2011

We study the stability and chaos of three compact objects using post-Newtonian (PN) equations of motion derived from the Arnowitt-Deser-Misner- Hamiltonian formulation. We include terms up to 2.5 PN order in the orbital part and the leading order in spin corrections. We performed numerical simulations of a hierarchical configuration of three compact bodies in which a binary system is perturbed by a third, lighter body initially positioned far away from the binary. The relative importance of the different PN orders is examined. The basin boundary method and the computation of Lyapunov exponent were employed to analyze the stability and chaotic properties of the system. The 1 PN terms produced a small but noticeable change in the stability regions of the parameters considered. The inclusion of spin or gravitational radiation does not produce a significant change with respect to the inclusion of the 1 PN terms. © 2011 American Physical Society.

Jousset A.,University of Gottingen | Jousset A.,University Utrecht | Eisenhauer N.,Friedrich - Schiller University of Jena | Materne E.,University of Gottingen | Scheu S.,University of Gottingen
Nature Communications | Year: 2013

Cooperation fundamentally contributes to the success of life on earth, but its persistence in diverse communities remains a riddle, as selfish phenotypes rapidly evolve and may spread until disrupting cooperation. Here we investigate how evolutionary history affects the emergence and spread of defectors in multispecies communities. We set up bacterial communities of varying diversity and phylogenetic relatedness and measure investment into cooperation (proteolytic activity) and their vulnerability to invasion by defectors. We show that evolutionary relationships predict the stability of cooperation: phylogenetically diverse communities are rapidly invaded by spontaneous signal-blind mutants (ignoring signals regulating cooperation), while cooperation is stable in closely related ones. Maintenance of cooperation is controlled by antagonism against defectors: cooperators inhibit phylogenetically related defectors, but not distant ones. This kin-dependent inhibition links phylogenetic diversity and evolutionary dynamics and thus provides a robust mechanistic predictor for the persistence of cooperation in natural communities.

Trinh L.T.T.,University of Oslo | Lambermont-Thijs H.M.L.,TU Eindhoven | Schubert U.S.,TU Eindhoven | Schubert U.S.,Friedrich - Schiller University of Jena | And 2 more authors.
Macromolecules | Year: 2012

Aqueous solutions of poly(2-oxazoline) block copolymers consisting of a 2-ethyl-2-oxazoline block and a block consisting of a random copolymer of 2-ethyl-2-oxazoline and 2-n-propyl-2-oxazoline (PEtOx-block-P(EtOx-stat-PropOx)) have been studied by dynamic light scattering (DLS), static light scattering (SLS), and turbidimetry. Even at temperatures significantly below the lower critical solution temperature (LCST), polymer unimers are found to coexist with a few large aggregates with an open structure. When heated, the systems exhibit an intricate transmittance behavior whereby the samples becomes visually clear again after an initial cloud point and then exhibit a second cloud point at even higher temperatures. The DLS data indicate that the aggregates formed around the first cloud point restructure and fragment into smaller micelle-like structures ascribed to further dehydration of the more hydrophobic PPropOx containing block, causing the samples to become optically clear again. The observed fragmentation is confirmed by the SLS experiments. At even higher temperatures, both blocks become hydrophobic, causing the formation of large, compact aggregates, resulting in a second cloud point. © 2012 American Chemical Society.

Hebenstreit F.,University of Graz | Alkofer R.,University of Graz | Gies H.,Friedrich - Schiller University of Jena
Physical Review Letters | Year: 2011

Nonperturbative electron-positron pair creation (the Schwinger effect) is studied based on the Dirac-Heisenberg-Wigner formalism in 1+1 dimensions. An ab initio calculation of the Schwinger effect in the presence of a simple space- and time-dependent electric field pulse is performed for the first time, allowing for the calculation of the time evolution of observable quantities such as the charge density, the particle number density or the total number of created particles. We predict a new self-bunching effect of charges in phase space due to the spatial and temporal structure of the pulse. © 2011 American Physical Society.

Schuetz G.M.,Charite - Medical University of Berlin | Schlattmann P.,Friedrich - Schiller University of Jena | Dewey M.,Charite - Medical University of Berlin
BMJ (Online) | Year: 2012

Objective: To determine whether a 3×2 table, using an intention to diagnose approach, is better than the "classic" 2×2 table at handling transparent reporting and non-evaluable results, when assessing the accuracy of a diagnostic test. Design: Based on a systematic search for diagnostic accuracy studies of coronary computed tomography (CT) angiography, full texts of relevant studies were evaluated to determine whether they could calculate an alternative 3×2 table. To quantify an overall effect, we pooled diagnostic accuracy values according to a meta-analytical approach. Data sources: Medline (via PubMed), Embase (via Ovid), and ISI Web of Science electronic databases. Eligibility criteria: Prospective English or German language studies comparing coronary CT with conventional coronary angiography in all patients and providing sufficient data for a patient level analysis. Results: 120 studies (10 287 patients) were eligible. Studies varied greatly in their approaches to handling non-evaluable findings. We found 26 studies (including 2298 patients) that allowed us to calculate both 2×2 tables and 3×2 tables. Using a bivariate random effects model, we compared the 2×2 table with the 3×2 table, and found significant differences for pooled sensitivity (98.2 (95% confidence interval 96.7 to 99.1) v 92.7 (88.5 to 95.3)), area under the curve (0.99 (0.98 to 1.00) v 0.93 (0.91 to 0.95)), positive likelihood ratio (9.1 (6.2 to 13.3) v 4.4 (3.3 to 6.0)), and negative likelihood ratio (0.02 (0.01 to 0.04) v 0.09 (0.06 to 0.15); (P<0.05)). Conclusion: Parameters for diagnostic performance significantly decrease if non-evaluable Results: are included by a 3×2 table for analysis (intention to diagnose approach). This approach provides a more realistic picture of the clinical potential of diagnostic tests.

Lesser T.G.,Friedrich - Schiller University of Jena
Surgical Endoscopy and Other Interventional Techniques | Year: 2012

Background Thoracoscopic resection of indeterminate pulmonary nodules is most commonly performed through three trocars using an endoscopic stapler. We assessed the safety, feasibility, and results of laser resection via minimal access under only local anesthesia. Methods Between September 2009 and June 2010, excision of subpleural nodules using laser application under only local anesthesia was performed in 28 patients (Laser group). A 2-mm trocar (minigrasper) and an 11-mm trocar (operating scope) were used. Anesthesia time, surgery time, global operating room time, chest tube time, piritramid dose, and hospital stay were assessed and compared with data from a patient group (n = 28) that required nodule resection through three trocars using an endoscopic stapler under general anesthesia (Control group). Results There was no mortality or major morbidity. There was no difference in technical feasibility between the groups. Two patients in the Laser group and one patient in the Control group required conversion to thoracotomy due to severe adhesions. The mean nodule size was 0.9 ± 0.2 cm in the Laser group and 1.0 ± 0.3 cm in the Control group (P = 0.05). Comparisons of Laser group results with Control group results showed that in the Laser group, anesthesia time (3 ± 0.7 vs. 42 ± 6.3 min, P < 0.001), global operating room time (51 ± 4.8 vs. 88 ± 10.8 min, P < 0.001), piritramid dose (65.9 ± 30.5 vs. 109.1 ± 21.9 mg, P < 0.001), and hospital stay (2.3 ± 0.9 vs. 3.2 ± 0.6 days, P < 0.001) were significantly reduced. Patients' satisfaction was high. Ninety-eight percent of patients said they would undergo this surgery again. Conclusion Awake thoracoscopic laser resection of subpleural pulmonary nodules proved safe and feasible. This technique may enable further reduction of invasiveness, length of hospital stay, and costs in selected patients. © Springer Science+Business Media, LLC 2011.

Baunach M.,Leibniz Institute for Natural Product Research and Infection Biology | Ding L.,Leibniz Institute for Natural Product Research and Infection Biology | Bruhn T.,University of Wurzburg | Bringmann G.,University of Wurzburg | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2013

Radical diversification: Through the discovery of diverse indolosesquiterpene dimers in a strain heterologously expressing the xiamycin biosynthesis genes, the analysis of mutants, and biotransformation studies, it has been inferred that a single flavoprotein mediates N-C and N-N aryl coupling reactions, as well as the formation of a cyclic ether (oxiamycin). Synthetic emulation of this unusual transformation provides evidence for a radical-based mechanism. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Franke J.,Leibniz Institute for Natural Product Research and Infection Biology | Ishida K.,Leibniz Institute for Natural Product Research and Infection Biology | Ishida-Ito M.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Friedrich - Schiller University of Jena
Angewandte Chemie - International Edition | Year: 2013

The elusive structure of malleobactin, a virulence factor of pathogens belonging to the Burkholderia mallei family, was finally unveiled by genetic and chemical analyses. The novel nitro-substituted siderophore is derived from an unusual, unprotected hydroxylamine, which undergoes spontaneous oxidation, as shown by in vitro assays and detection of analogues featuring hydroxylamino, nitroso, and azoxide groups. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Betzler N.,Friedrich - Schiller University of Jena | Dorn B.,University of Tubingen
Journal of Computer and System Sciences | Year: 2010

To make a joint decision, agents (or voters) are often required to provide their preferences as linear orders. To determine a winner, the given linear orders can be aggregated according to a voting protocol. However, in realistic settings, the voters may often only provide partial orders. This directly leads to the PossibleWinner problem that asks, given a set of partial votes, whether a distinguished candidate can still become a winner. In this work, we consider the computational complexity of Possible Winner for the broad class of voting protocols defined by scoring rules. A scoring rule provides a score value for every position which a candidate can have in a linear order. Prominent examples include plurality, k-approval, and Borda. Generalizing previous NP-hardness results for some special cases, we settle the computational complexity for all but one scoring rule. More precisely, for an unbounded number of candidates and unweighted voters, we show that Possible Winner is NP-complete for all pure scoring rules except plurality, veto, and the scoring rule defined by the scoring vector (2, 1,..., 1, 0), while it is solvable in polynomial time for plurality and veto. © 2010 Elsevier Inc. All rights reserved.

Ueberschaar N.,Leibniz Institute for Natural Product Research and Infection Biology | Dahse H.-M.,Leibniz Institute for Natural Product Research and Infection Biology | Bretschneider T.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Leibniz Institute for Natural Product Research and Infection Biology | Hertweck C.,Friedrich - Schiller University of Jena
Angewandte Chemie - International Edition | Year: 2013

Light on DNA intercalators: Molecular modeling and mutasynthesis were employed to rationally tailor the antitumoral agent chartreusin into a vinyl-substituted derivative. Exposure with visible light dramatically improved antiproliferative activities owing to covalent binding with DNA and induction of apoptosis. The results hold promise for a more efficient chemotherapy, in particular for selectively treating tumors with light probes. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Scriba G.K.E.,Friedrich - Schiller University of Jena
Topics in Current Chemistry | Year: 2013

Capillary electrophoresis (CE) hasmatured to one of the major liquid phase enantiodifferentiation techniques since the first report in 1985. This can be primarily attributed to the flexibility as well as the various modes available including electrokinetic chromatography (EKC), micellar electrokinetic chromatography (MEKC), and microemulsion electrokinetic chromatography (MEEKC). In contrast to chromatographic techniques, the chiral selector is mobile in the background electrolyte. Furthermore, a large variety of chiral selectors are available that can be easily combined in the same separation system. In addition, the migration order of the enantiomers can be adjusted by a number of approaches. In CE enantiodifferentiations the separation principle is comparable to chromatography while the principle of the movement of the analytes in the capillary is based on electrophoretic phenomena. The present chapter will focus on mechanistic aspects of CE enantioseparations including enantiomer migration order and the current understanding of selector-selectand structures. Selected examples of the basic enantioseparation modes EKC, MEKC, and MEEKC will be discussed. © Springer-Verlag Berlin Heidelberg 2013.

Gimpel M.,AG Bakteriengenetik | Preis H.,AG Bakteriengenetik | Barth E.,AG Bakteriengenetik | Gramzow L.,Friedrich - Schiller University of Jena | Brantl S.,AG Bakteriengenetik
Nucleic Acids Research | Year: 2012

SR1 is a dual-function sRNA that acts as a base-pairing regulatory RNA on the ahrC mRNA and as a peptide-encoding mRNA on the gapA operon. The SR1-encoded peptide SR1P binds GapA thereby stabilizing gapA mRNA. Under glycolytic conditions, SR1 transcription is repressed by CcpN and CcpA. A computer-based search identified 23 SR1 homologues in Bacillus, Geobacillus, Anoxybacillus and Brevibacillus species. All homologues share a high structural identity with Bacillus subtilis SR1, and the encoded SR1P peptides are highly similar. In the Bacillus cereus group, the sr1p region is present in triplicate or duplicate resulting in longer SR1 species. In all cases, sr1 expression is under control of CcpN, and transcriptional lacZ fusions of nine examined SR1 homologues were sensitive to glucose. Two homologues showed an additional glucose-independent repression by CcpN and an unknown factor. A total of 10 out of 11 tested SR1P homologues complemented a B. subtilis Δsr1 strain in their ability to stabilize gapA mRNA, but only five of them bound GapA tightly. In vitro binding assays with six SR1/ahrC pairs suggest that-despite divergent primary sequences-the base-pairing function is also preserved. In summary, SR1 is an sRNA with two functions that have been conserved over ≈1 billion years. © 2012 The Author(s).

Hessel V.,TU Eindhoven | Kralisch D.,Friedrich - Schiller University of Jena | Kockmann N.,TU Dortmund | Noel T.,TU Eindhoven | Wang Q.,TU Eindhoven
ChemSusChem | Year: 2013

Novel Process Windows make use of process conditions that are far from conventional practices. This involves the use of high temperatures, high pressures, high concentrations (solvent-free), new chemical transformations, explosive conditions, and process simplification and integration to boost synthetic chemistry on both the laboratory and production scale. Such harsh reaction conditions can be safely reached in microstructured reactors due to their excellent transport intensification properties. This Review discusses the different routes towards Novel Process Windows and provides several examples for each route grouped into different classes of chemical and process-design intensification. © 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pergushov D.V.,Moscow State University | Muller A.H.E.,University of Bayreuth | Schacher F.H.,Friedrich - Schiller University of Jena
Chemical Society Reviews | Year: 2012

Interpolyelectrolyte complexes (IPECs) are typically formed when two polyelectrolytes of opposite charge are mixed together in solution. We present an overview of different strategies for the preparation of micellar IPECs, i.e., structures where such IPEC domains form the core or the shell of micelles. In addition, vesicular architectures are considered, where the IPEC domain forms a membrane layer. One intriguing feature of IPECs is that their formation can be directed, their stability towards changes in pH or ionic strength can (to a certain extent) be predicted, and their size can be controlled. Especially the use of ionic/non-ionic block copolymers offers unique potential for the preparation of well-defined and sophisticated nanostructured materials. We also discuss possible applications, especially in the field of life sciences, including biocompatibility, the controlled uptake/release of guest substances, the immobilization of enzymes, or the controlled formation of inorganic/organic hybrid materials. © 2012 The Royal Society of Chemistry.

Galicki M.,University of Zielona Gora | Galicki M.,Friedrich - Schiller University of Jena
Robotica | Year: 2011

This study offers the solution of the end-effector trajectory tracking problem subject to state constraints, suitably transformed into control-dependent ones, for mobile manipulators. Based on the Lyapunov stability theory, a class of controllers fulfilling the above constraints and generating the mobile manipulator trajectory with (instantaneous) minimal energy, is proposed. The problem of manipulability enforcement is solved here based on an exterior penalty function approach which results in continuous mobile manipulator controls even near boundaries of state constraints. The numerical simulation results carried out for a mobile manipulator consisting of a non-holonomic unicycle and a holonomic manipulator of two revolute kinematic pairs, operating in a two-dimensional task space, illustrate the performance of the proposed controllers. © 2010 Cambridge University Press.

Galicki M.,University of Zielona Gora | Galicki M.,Friedrich - Schiller University of Jena
Mechanical Systems and Signal Processing | Year: 2011

This work offers the solution at the control feed-back level of the end-effector trajectory tracking problem for mobile manipulators subject to state equality and/or inequality constraints, suitably transformed into control dependent ones. Based on the Lyapunov stability theory, a class of controllers fulfilling the above constraints and generating a collision-free mobile manipulator trajectory with (instantaneous) minimal energy, is proposed. The problem of collision avoidance is solved here based on an exterior penalty function approach which results in continuous and bounded mobile manipulator controls even near boundaries of obstacles. The numerical simulation results carried out for a mobile manipulator consisting of a non-holonomic unicycle and a holonomic manipulator of two revolute kinematic pairs, operating both in a two-dimensional unconstrained task space and task space including the obstacles, illustrate the performance of the proposed controllers. © 2010 Elsevier Ltd. All rights reserved.

Rennert T.,Friedrich - Schiller University of Jena | Rinklebe J.,University of Wuppertal
Water, Air, and Soil Pollution | Year: 2010

As floodplain soils are often contaminated, we studied the release of trace metals from three topsoil horizons in column experiments with variable flow interruptions and flow velocities, compared it with that in batch leaching tests and evaluated the column data by inverse simulations. Only small proportions (<1%) of trace metals present in the neutral and humic soils were mobilised by the batch leaching tests and the column experiments. Release of Cr, Cu, Ni and Zn in the column experiments was rate-limited, as detected by increased concentrations after flow interruptions. A combination of linear equilibrium and non-equilibrium isotherms reflected the Ni and Zn elution data, with Zn release being slower. Simulated values for initially bound metals available for release are in the same order of magnitude as those determined by the batch leaching tests. However, the consistency of both experimental approaches decreases with increasing rate limitation, as detected here for Zn. © 2009 Springer Science+Business Media B.V.

Stolle A.,Friedrich - Schiller University of Jena
European Journal of Organic Chemistry | Year: 2013

The synthesis of nopinone from β-pinene is an interesting model reaction for the investigation of methods for the oxidative cleavage of C=C bonds. Nopinone is used as chiral component for the total synthesis of different ligands or natural compounds such as di- or sesquiterpenes, as well as for the production of pharmaceutically active components. The cleavage of the C(2)=C(10) bond in β-pinene by suitable oxidants leads to the replacement of the exo-methylene functionality by a carbonyl group, which is more suitable for subsequent synthetic steps and the construction of complex condensed ring systems. Oxidants such as ozone, potassium permanganate, or sodium periodate have been applied successfully for this reaction. Ozonolysis of the double bond follows the classical Criegee mechanism, after which the secondary intermediate is isolated and reductive workup yields the carbonyl products. Dihydroxylation of the double bond can be initiated by permanganate or periodate. Further oxidation leads to the same products known from ozonolysis. Periodate oxidations in particular can be supported by catalysts such as RuCl3 or OsO4, because the oxidant is generally too weak to dihydroxylate the double bond. OsO4-catalyzed reactions, for example, can take advantage of a co-oxidant such as trimethylammonium N-oxide for the dihydroxylation step. Other oxidants such as hydrogen peroxide or dioxygen have also been tested but with minor success with respect to conversion or selectivity. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Schaible H.-G.,Friedrich - Schiller University of Jena
Current Rheumatology Reports | Year: 2012

Pain is a major clinical problem of osteoarthritis (OA). Recently, OA has been thought to be a disease of the whole joint with both destruction of cartilage and inflammatory components such as synovitis and bone marrow lesions. Clinical studies have documented a significant inflammatory soft tissue contribution to the severity and frequency of OA pain. Both clinical and experimental studies have provided evidence for the sensitization of pain pathways during OA, involving pronounced changes in joint nociceptors and changes of the nociceptive processing in the spinal cord, brainstem, and thalamocortical system. Additionally, evidence has been provided for neuropathic pain components in OA models. Concerning molecular mechanisms of OA pain and potential options for pain therapy, studies on nerve growth factor, cytokines, sodium channel blockers, hyaluronic acid preparations, and others are addressed in this review. © Springer Science+Business Media, LLC 2012.

Aminake M.N.,University of Wurzburg | Arndt H.-D.,Friedrich - Schiller University of Jena | Pradel G.,University of Wurzburg
International Journal for Parasitology: Drugs and Drug Resistance | Year: 2012

The ubiquitin/proteasome system serves as a regulated protein degradation pathway in eukaryotes, and is involved in many cellular processes featuring high protein turnover rates, such as cell cycle control, stress response and signal transduction. In malaria parasites, protein quality control is potentially important because of the high replication rate and the rapid transformations of the parasite during life cycle progression. The proteasome is the core of the degradation pathway, and is a major proteolytic complex responsible for the degradation and recycling of non-functional ubiquitinated proteins. Annotation of the genome for Plasmodium falciparum, the causative agent of malaria tropica, revealed proteins with similarity to human 26S proteasome subunits. In addition, a bacterial ClpQ/hslV threonine peptidase-like protein was identified. In recent years several independent studies indicated an essential function of the parasite proteasome for the liver, blood and transmission stages. In this review, we compile evidence for protein recycling in Plasmodium parasites and discuss the role of the 26S proteasome as a prospective multi-stage target for antimalarial drug discovery programs. © 2011 Australian Society for Parasitology.

Georg I.,University of Cape Town | Schafer G.,Friedrich - Schiller University of Jena
Classical and Quantum Gravity | Year: 2015

Based on a recent paper by Rothe and Schäfer on compact binary systems (Rothe and Schäfer 2010 J. Math. Phys. 51 082501), explicit expressions for canonical center and relative coordinates in terms of standard canonical coordinates are derived for spinless objects up to second post-Newtonian (PN) approximation of Einstein's theory of gravity (the third post-Newtonian order expressions are available in the form of supplementary data). The inverse relations, i.e. the dependence of the standard canonical coordinates on the canonical center and relative coordinates, are also given up to the second PN approximation. The famous Pythagorean-theorem-type Lorentz-invariant relation between the system's total energy or Hamiltonian squared, the rest energy or mass squared - solely depending on relative coordinates - and the total linear momentum squared, are explicitly shown through second PN approximation. © 2015 IOP Publishing Ltd.

Mueller C.K.,Friedrich - Schiller University of Jena
The International journal of oral & maxillofacial implants | Year: 2011

The structure of peri-implant soft tissue that is regenerated after flapless and flap surgery has been shown to differ. However, its underlying mechanisms are relatively unknown. The present study sought to identify differences in the inflammatory cell infiltration and expression of gene transcripts during transmucosal healing between the two approaches with two different implant designs. All mandibular premolars were removed from 12 minipigs. One month later, four implants (two NobelReplace Tapered Groovy and two NobelPerfect Groovy, Nobel Biocare) were placed in each quadrant. One quadrant was randomized to flapless insertion, while the other was chosen for flap surgery in each animal. Following 1, 2, 4, and 12 weeks of transmucosal implant healing, biopsy specimens were retrieved from the peri-implant soft tissue according to a standardized procedure to avoid crossover effects. Samples were subjected to a leukocyte count and a gene expression analysis. When the flapless placement technique was used, leukocyte influx in the peri-implant soft tissue was significantly smaller compared to open surgery for both implant designs. Gene expression analysis revealed significant overexpression of molecules associated with detoxification and reepithelialization in the flapless group. In contrast, myofibroblast-associated gene transcripts were significantly enriched in the flap surgery group. The present data indicate perpetuation of inflammatory reactions as well as increased fibrotic scar tissue deposition in the peri-implant area following implant placement by the flap approach. Flapless implant insertion results in less inflammation and early reepithelialization, providing the potential for the formation of a fully functioning as well as esthetically preferable peri-implant soft tissue collar.

Schmidt G.W.,University of Adelaide | Schmidt G.W.,Friedrich - Schiller University of Jena | Delaney S.K.,University of Adelaide | Delaney S.K.,University of New South Wales
Molecular Genetics and Genomics | Year: 2010

Real-time RT-PCR is a powerful technique for the measurement of gene expression, but its accuracy depends on the stability of the internal reference gene(s) used for data normalization. Tobacco (Nicotiana tabacum) is an important model in studies of plant gene expression, but stable reference genes have not been well-studied in the tobacco system. We address this problem by analysing the expression stability of eight potential tobacco reference genes. Primers targeting each gene (18S rRNA, EF-1α, Ntubc2, α- and β-tubulin, PP2A, L25 and actin) were developed and optimized. The expression of each gene was then measured by real-time PCR in a diverse set of 22 tobacco cDNA samples derived from developmentally distinct tissues and from plants exposed to several abiotic stresses. L25 and EF-1α demonstrated the highest expression stability, followed by Ntubc2. Measurement of L25 and EF-1α was sufficient for accurate normalization in either the developmental or stress-treated samples, but Ntubc2 was also required when considering the entire sample set. Analysis of a tobacco circadian gene (NTCP-23) verified these reference genes in an additional context, and all techniques were optimized to enable a high-throughput approach. These results provide a foundation for the more accurate and widespread use of real-time RT-PCR in tobacco. © 2010 Springer-Verlag.

Mammalian locomotion is characterized by the frequent use of in-phase gaits in which the footfalls of the left and right fore- or hindlimbs are unevenly spaced in time. Although previous studies have identified a functional differentiation between the first limb (trailing limb) and the second limb (leading limb) to touch the ground during terrestrial locomotion, the influence of a horizontal branch on limb function has never been explored. To determine the functional differences between trailing and leading forelimbs during locomotion on the ground and on a horizontal branch, X-ray motion analysis and force measurements were carried out in two European red squirrels (Sciurus vulgaris, Rodentia). The differences observed between trailing and leading forelimbs were minimal during terrestrial locomotion, where both limbs fulfill two functions and go through a shock-absorbing phase followed by a generating phase. During locomotion on a horizontal branch, European red squirrels reduce speed and all substrate reaction forces transmitted may be due to the reduction of vertical oscillation of the center of mass. Further adjustments during locomotion on a horizontal branch differ significantly between trailing and leading forelimbs and include limb flexion, lead intervals, limb protraction and vertical displacement of the scapular pivot. Consequently, trailing and leading forelimbs perform different functions. Trailing forelimbs function primarily as shock-absorbing elements, whereas leading forelimbs are characterized by a high level of stiffness. This functional differentiation indicates that European red squirrels 'test' the substrate for stability with the trailing forelimb, while the leading forelimb responds to or counteracts swinging or snapping branches. © 2011 Elsevier GmbH.

Teschke R.,Goethe University Frankfurt | Wolff A.,Friedrich - Schiller University of Jena | Frenzel C.,University of Hamburg | Schulze J.,Goethe University Frankfurt
Alimentary Pharmacology and Therapeutics | Year: 2014

Background Although evidence for their therapeutic efficacy is limited, herbal traditional Chinese medicine (TCM) preparations increasingly gain popularity. In contrast to other herbal products, adverse effects by herbal TCM including liver toxicity were rarely reported. In recent years, more cases were published, providing new clinical challenges. Aim To summarise comprehensively the literature on herbal TCM hepatotoxicity since 2011. Methods PubMed was searched using key words related to TCM, the results were restricted to full English-language publications and abstracts published since 2011. In addition, the database of the National Institutes of Health (NIH) and LiverTox was accessed under the topic 'Drug record: Chinese and other Asian herbal medicines'. Results Since 2011, new case reports and case series provided evidence for herbal hepatotoxicity by TCM, focusing on nine TCM herbal mixtures and four individual TCM herbs with potential health hazards. These were the TCM products Ban Tu Wan, Chai Hu, Du Huo, Huang Qin, Jia Wei Xia Yao San, Jiguja, Kamishoyosan, Long Dan Xie Gan Tang, Lu Cha, Polygonum multiflorum products, Shan Chi, 'White flood' containing the herbal TCM Wu Zhu Yu and Qian Ceng Ta, and Xiao Chai Hu Tang. Other developments include the establishment of a new and early diagnostic serum marker for hepatotoxicity caused by pyrrolizidine alkaloids, assessed using ultra performance liquid chromatography-mass spectrometry analysis, and new regulatory details to improve herbal TCM product quality and safety. Conclusion Stringent evaluation of the risk/benefit ratio is essential to protect traditional Chinese medicines users from health hazards including liver injury. © 2014 John Wiley & Sons Ltd.

Birringer M.,Friedrich - Schiller University of Jena
Molecular Nutrition and Food Research | Year: 2010

Vitamin E is known as the most important lipid antioxidant and is widely used to prevent age-associated diseases. Despite increasing knowledge about human vitamin E metabolism, little is known to justify its widespread use. As meta-analyses revealed even harmful effects of high vitamin E doses, a profound understanding of vitamin E metabolism is mandatory. By recent advances in analytical methodology, new metabolites with distinct physicochemical and biological properties were discovered. This review covers current methods to analyze vitamin E metabolites in biological samples. Special emphasis is laid on analytical applications for the identification and quantification of metabolites with a modified hydroxychromanol ring or a truncated side chain. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pleuger J.,Friedrich - Schiller University of Jena | Pleuger J.,ETH Zurich | Podladchikov Y.Y.,University of Lausanne
Tectonics | Year: 2014

Common extrusion-type models for the high- to ultrahigh-pressure Adula nappe require a major normal fault along the top of this unit which is not conveyed in the structural record. This implies that such a normal fault existed but was completely erased during later deformational stages. However, there is evidence that decompression occurred during top-to-the-foreland thrusting. We performed a new, purely structural kinematic restoration of the central part of the NFP20-East cross section in order to estimate the burial depths of individual units without converting petrological pressure data into depth under the assumption that pressures were lithostatic. The results show that pressures within most of the units were close to but somewhat higher than lithostatic for several stages of the tectono-metamorphic history. Only for the maximum burial stage of the Adula nappe, we estimate local tectonic overpressures of 40 to 80% of the lithostatic pressures. Accepting such an amount of overpressure, which is moderate compared to values theoretically possible, the Adula nappe was probably not subducted to subcrustal depth. We propose that the structural record of the Penninic nappe stack is quite complete and suggest that the decay of tectonic overpressure is a feasible explanation for decompression from eclogite- to amphibolite-facies conditions during thrusting. Consequen