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Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.
Im Auftrag des Staates
(2011)
Folter ist ein Akt extremer kollektiver Gewalt, der im Auftrag eines Staates im Geheimen ausgeübt wird. Die Frage, was Menschen dazu bringt, anderen Menschen diese extreme Gewalt anzutun, verengt den Blick für ein Verständnis der Folter allzu schnell auf individualistische Erklärungsversuche. Der vorliegende Aufsatz geht im Gegensatz dazu von der Gruppe der Folterer aus und rückt die sozialen Beziehungen dieser Form der Vergesellschaftung und die von ihnen ausgehenden sozialen Dynamiken und Effekte in den Mittelpunkt. In einem ersten Schritt werden Georg Simmels formale Bestimmungen der geheimen Gesellschaft rekonstruiert und auf die geheime Gesellschaft der Folterer angewandt und spezifiziert; auf dieser Grundlage werden im zweiten Schritt Handlungsbedingungen der Mitglieder der geheimen Gesellschaft der Folterer herausgearbeitet; der dritte Schritt bestimmt die eigendynamischen Prozesse des Phänomens der Folter, die aus der Eskalation politischer Konflikte, der Gruppe der Folterer und der Situation der Folter erwachsen. Die These lautet, dass sich aus der Perspektive einer relationalen Soziologie ein theoretischer Zugriff auf das Problem der Folter ergibt, der weiterführende Erklärungen des Phänomens ermöglicht.
Sobre los orígenes y la evaluación de los Germanos en la literatura alemana de los siglos XVI
(2011)
Los conceptos que tenían los habitantes del Sacro Imperio Romano sobre la nación germana respecto a su filiación étnica y sus orígenes cambian a partir del inicio de la historia moderna. A través del análisis de los ejemplos más relevantes el presente estudio traza las líneas maestras de este proceso de apropiación e interpretción del pasado que empieza con la recepción de la Germania de Tácito por los escritores humanistas y se prolonga a lo largo de los siglos XVII, XVIII y XIX.
Moderne Bürgerreligion
(2011)
Process analysis usually focuses only on single and selected processes. It is either existent processes that are recorded and analysed or reference processes that are implemented. So far no evident effort has been put into generalising specific process aspects into patterns and comparing those patterns with regard to their efficiency and effectiveness. This article focuses on the combination of dynamic and holistic analytical elements in enterprise architectures. Our goal is to outline an approach to analyse the development of business processes in a cyclical matter and demonstrate this approach based on an existent modelling language. We want to show that organisational learning can derive from the systematic analysis of past and existent processes from which patterns of successful problem solving can be deducted.
In vorliegender Arbeit werden die Gefahren und Chancen des gemeinschaftlichen Zusammenlebens im Exil am Beispiel der ehemaligen Colonia Dignidad in Chile analysiert. Die Colonia Dignidad (dt.: Kolonie der Würde) wurde 1961 von Mitgliedern einer deutschen Sekte im Zentrum des Landes, ca. 400 km südlich von Santiago entfernt, gegründet. Nach außen präsentierte sich die Gemeinschaft als glückliche und zufriedene deutsche Enklave, die ihre heimatlichen Traditionen und Bräuche im Ausland weiterhin pflegt. Mit dem Ende der Militärdiktatur unter Augusto Pinochet 1990 und dem damit verbundenen Wegfall der politischen Rückendeckung der Gemeinschaft, begann die chilenische Justiz die schon länger bestehenden Vorwürfe gegen den damaligen Sektenführer Paul Schäfer, u. a. wegen Kindesmissbrauchs und Folter an chilenischen Oppositionellen während der Militärdiktatur, zu untersuchen. Dem chilenischen Haftbefehl acht Jahre später entzog sich Paul Schäfer durch seine Flucht nach Argentinien. Die zurückbleibenden Mitglieder der Colonia Dignidad waren aufgrund des einsetzenden Zerfalls der alten Gemeinschaftsordnung gezwungen, sich ein neues Gemeinschaftskonzept zu erarbeiten, eines, in dem die bisher so dominante Führerfigur fehlte.
Sowohl das Gemeinschaftsleben in der Colonia Dignidad zwischen 1961 und 1998 als auch das Zusammenleben in der heutigen Villa Baviera ab 1998 wird anhand der Theorien zur Gemeinschaftsforschung von Ferdinand Tönnies, Georg Vobruba, Zygmunt Baumann, Matthias Grundmann und Stephan Drucks analysiert. Im Findungsprozess eines neuen Gemeinschaftskonzeptes waren die Mitglieder der ehemaligen Colonia Dignidad gezwungen, sich mit der Vergangenheit auseinanderzusetzen. In diesem Zusammenhang wird der Frage nachgegangen, inwiefern eine Aufarbeitung der Vergangenheit (memoria) im kulturwissenschaftlichen und psychologischen Sinne stattfand bzw. stattfindet und wenn ja, wie sich diese gestaltete bzw. gestaltet. Hierzu wird untersucht, welche staatlichen Maßnahmen zur Unterstützung des Neuanfangs der Gemeinschaft getroffen wurden und welchen Erfolg diese Maßnahmen hatten. Basierend auf den daraus gewonnenen Resultaten und der aktuellen Selbstdarstellung der Villa Baviera in ihrer Webpräsenz, wird das neue Gemeinschaftskonzept der ehemaligen Colonia Dignidad auf die Chancen des Zusammenlebens hin analysiert. Weiterführend werden Konzepte zum kollektiven Gedächtnis untersucht, von dem „Familiengedächtnis“ auf ein „Gemeinschaftsgedächtnis“ übertragen und mit der Frage nach der konstruktiven memoria innerhalb der Villa Baviera verbunden. Abschließend wird der Frage nachgegangen, welche positiven Aspekte des Gemeinschaftslebens einer intentionalen Gemeinschaft auf das Gemeinschaftsleben der Villa Baviera übertragen werden könnten.
Background: The ability to create nanostructures with biomolecules is one of the key elements in nanobiotechnology. One of the problems is the expensive and mostly custom made equipment which is needed for their development. We intended to reduce material costs and aimed at miniaturization of the necessary tools that are essential for nanofabrication. Thus we combined the capabilities of molecular ink lithography with DNA-self-assembling capabilities to arrange DNA in an independent array which allows addressing molecules in nanoscale dimensions.
Results: For the construction of DNA based nanostructures a method is presented that allows an arrangement of DNA strands in such a way that they can form a grid that only depends on the spotted pattern of the anchor molecules. An atomic force microscope (AFM) has been used for molecular ink lithography to generate small spots. The sequential spotting process allows the immobilization of several different functional biomolecules with a single AFM-tip. This grid which delivers specific addresses for the prepared DNA-strand serves as a two-dimensional anchor to arrange the sequence according to the pattern. Once the DNA-nanoarray has been formed, it can be functionalized by PNA (peptide nucleic acid) to incorporate advanced structures.
Conclusions: The production of DNA-nanoarrays is a promising task for nanobiotechnology. The described method allows convenient and low cost preparation of nanoarrays. PNA can be used for complex functionalization purposes as well as a structural element.
Background
In many species males face a higher predation risk than females because males display elaborate traits that evolved under sexual selection, which may attract not only females but also predators. Females are, therefore, predicted to avoid such conspicuous males under predation risk. The present study was designed to investigate predator-induced changes of female mating preferences in Atlantic mollies (Poecilia mexicana). Males of this species show a pronounced polymorphism in body size and coloration, and females prefer large, colorful males in the absence of predators.
Results
In dichotomous choice tests predator-naïve (lab-reared) females altered their initial preference for larger males in the presence of the cichlid Cichlasoma salvini, a natural predator of P. mexicana, and preferred small males instead. This effect was considerably weaker when females were confronted visually with the non-piscivorous cichlid Vieja bifasciata or the introduced non-piscivorous Nile tilapia (Oreochromis niloticus). In contrast, predator experienced (wild-caught) females did not respond to the same extent to the presence of a predator, most likely due to a learned ability to evaluate their predators' motivation to prey.
Conclusions
Our study highlights that (a) predatory fish can have a profound influence on the expression of mating preferences of their prey (thus potentially affecting the strength of sexual selection), and females may alter their mate choice behavior strategically to reduce their own exposure to predators. (b) Prey species can evolve visual predator recognition mechanisms and alter their mate choice only when a natural predator is present. (c) Finally, experiential effects can play an important role, and prey species may learn to evaluate the motivational state of their predators.
Background
More than in other domains the heterogeneous services world in bioinformatics demands for a methodology to classify and relate resources in a both human and machine accessible manner. The Semantic Web, which is meant to address exactly this challenge, is currently one of the most ambitious projects in computer science. Collective efforts within the community have already led to a basis of standards for semantic service descriptions and meta-information. In combination with process synthesis and planning methods, such knowledge about types and services can facilitate the automatic composition of workflows for particular research questions.
Results
In this study we apply the synthesis methodology that is available in the Bio-jETI workflow management framework for the semantics-based composition of EMBOSS services. EMBOSS (European Molecular Biology Open Software Suite) is a collection of 350 tools (March 2010) for various sequence analysis tasks, and thus a rich source of services and types that imply comprehensive domain models for planning and synthesis approaches. We use and compare two different setups of our EMBOSS synthesis domain: 1) a manually defined domain setup where an intuitive, high-level, semantically meaningful nomenclature is applied to describe the input/output behavior of the single EMBOSS tools and their classifications, and 2) a domain setup where this information has been automatically derived from the EMBOSS Ajax Command Definition (ACD) files and the EMBRACE Data and Methods ontology (EDAM). Our experiments demonstrate that these domain models in combination with our synthesis methodology greatly simplify working with the large, heterogeneous, and hence manually intractable EMBOSS collection. However, they also show that with the information that can be derived from the (current) ACD files and EDAM ontology alone, some essential connections between services can not be recognized.
Conclusions
Our results show that adequate domain modeling requires to incorporate as much domain knowledge as possible, far beyond the mere technical aspects of the different types and services. Finding or defining semantically appropriate service and type descriptions is a difficult task, but the bioinformatics community appears to be on the right track towards a Life Science Semantic Web, which will eventually allow automatic service composition methods to unfold their full potential.
Dutch allows for variation as to whether the first position in the sentence is occupied by the subject or by some other constituent, such as the direct object. In particular situations, however, this commonly observed variation in word order is ‘frozen’ and only the subject appears in first position. We hypothesize that this partial freezing of word order in Dutch can be explained from the dependence of the speaker’s choice of word order on the hearer’s interpretation of this word order. A formal model of this interaction between the speaker’s perspective and the hearer’s perspective is presented in terms of bidirectional Optimality Theory. Empirical predictions of this model regarding the interaction between word order and definiteness are confirmed by a quantitative corpus study.
Many organisms have developed defences to avoid predation by species at higher trophic levels. The capability of primary producers to defend themselves against herbivores affects their own survival, can modulate the strength of trophic cascades and changes rates of competitive exclusion in aquatic communities. Algal species are highly flexible in their morphology, growth form, biochemical composition and production of toxic and deterrent compounds. Several of these variable traits in phytoplankton have been interpreted as defence mechanisms against grazing. Zooplankton feed with differing success on various phytoplankton species, depending primarily on size, shape, cell wall structure and the production of toxins and deterrents. Chemical cues associated with (i) mechanical damage, (ii) herbivore presence and (iii) grazing are the main factors triggering induced defences in both marine and freshwater phytoplankton, but most studies have failed to disentangle the exact mechanism(s) governing defence induction in any particular species. Induced defences in phytoplankton include changes in morphology (e.g. the formation of spines, colonies and thicker cell walls), biochemistry (such as production of toxins, repellents) and in life history characteristics (formation of cysts, reduced recruitment rate). Our categorization of inducible defences in terms of the responsible induction mechanism provides guidance for future work, as hardly any of the available studies on marine or freshwater plankton have performed all the treatments that are required to pinpoint the actual cue(s) for induction. We discuss the ecology of inducible defences in marine and freshwater phytoplankton with a special focus on the mechanisms of induction, the types of defences, their costs and benefits, and their consequences at the community level.
Fusarium spp. infection of cereal grain is a common problem, which leads to a dramatic loss of grain quality. The aim of the present study was to investigate the effect of Fusarium infection on the wheat storage protein gluten and its fractions, the gliadins and glutenins, in an in vitro model system. Gluten proteins were digested by F. graminearum proteases for 2, 4, 8 and 24 h, separated by Osborne fractionation and characterised by chromatographic (RP-HPLC) and electrophoretic analysis (SDS-Page). Gluten digestion by F. graminearum proteases showed in comparison with gliadins a preference for the glutenins whereas the HMW subfraction was at most affected. In comparison with a untreated control, the HMW subfraction was degraded of about 97% after 4 h incubation with Fusarium proteases. Separate digestion of gliadin and glutenin underlined the preference for HMW-GS. Analogue to the observed change in the gluten composition, the yield of the proteins extracted changed. A higher amount of glutenin fragments was found in the gliadin extraction solution after digestion and could mask a gliadin destruction at the same time. This observation can contribute to explain the frequently reported reduced glutenin amount parallel to an increase in gliadin quantity after Fusarium infection in grains.
Background
Riociguat is the first of a new class of drugs, the soluble guanylate cyclase (sGC) stimulators. Riociguat has a dual mode of action: it sensitizes sGC to the body’s own NO and can also increase sGC activity in the absence of NO. The NO-sGC-pathway is impaired in many cardiovascular diseases such as heart failure, pulmonary hypertension and diabetic nephropathy (DN). DN leads to high cardiovascular morbidity and mortality. There is still a high unmet medical need. The urinary albumin excretion rate is a predictive biomarker for these clinical events. Therefore, we investigated the effect of riociguat, alone and in combination with the angiotensin II receptor antagonist (ARB) telmisartan on the progression of DN in diabetic eNOS knock out mice, a new model closely resembling human pathology.
Methods
Seventy-six male eNOS knockout C57BL/6J mice were divided into 4 groups after receiving intraperitoneal high-dose streptozotocin: telmisartan (1 mg/kg), riociguat (3 mg/kg), riociguat+telmisartan (3 and 1 mg/kg), and vehicle. Fourteen mice were used as non-diabetic controls. After 12 weeks, urine and blood were obtained and blood pressure measured. Glucose concentrations were highly increased and similar in all diabetic groups.
Results
Riociguat, alone (105.2 ± 2.5 mmHg; mean±SEM; n = 14) and in combination with telmisartan (105.0 ± 3.2 mmHg; n = 12), significantly reduced blood pressure versus diabetic controls (117.1 ± 2.2 mmHg; n = 14; p = 0.002 and p = 0.004, respectively), whereas telmisartan alone (111.2 ± 2.6 mmHg) showed a modest blood pressure lowering trend (p = 0.071; n = 14). The effects of single treatment with either riociguat (97.1 ± 15.7 µg/d; n = 13) or telmisartan (97.8 ± 26.4 µg/d; n = 14) did not significantly lower albumin excretion on its own (p = 0.067 and p = 0.101, respectively). However, the combined treatment led to significantly lower urinary albumin excretion (47.3 ± 9.6 µg/d; n = 12) compared to diabetic controls (170.8 ± 34.2 µg/d; n = 13; p = 0.004), and reached levels similar to non-diabetic controls (31.4 ± 10.1 µg/d, n = 12).
Conclusion
Riociguat significantly reduced urinary albumin excretion in diabetic eNOS knock out mice that were refractory to treatment with ARB’s alone. Patients with diabetic nephropathy refractory to treatment with ARB’s have the worst prognosis among all patients with diabetic nephropathy. Our data indicate that additional stimulation of sGC on top of standard treatment with ARB`s may offer a new therapeutic approach for patients with diabetic nephropathy resistant to ARB treatment.
Due to their optical and electro-conductive attributes, carbazole derivatives are interesting materials for a large range of biosensor applications. In this study, we present the synthesis routes and fluorescence evaluation of newly designed carbazole fluorosensors that, by modification with uracil, have a special affinity for antiretroviral drugs via either Watson–Crick or Hoogsteen base pairing. To an N-octylcarbazole-uracil compound, four different groups were attached, namely thiophene, furane, ethylenedioxythiophene, and another uracil; yielding four different derivatives. Photophysical properties of these newly obtained derivatives are described, as are their interactions with the reverse transcriptase inhibitors such as abacavir, zidovudine, lamivudine and didanosine. The influence of each analyte on biosensor fluorescence was assessed on the basis of the Stern–Volmer equation and represented by Stern–Volmer constants. Consequently we have demonstrated that these structures based on carbazole, with a uracil group, may be successfully incorporated into alternative carbazole derivatives to form biosensors for the molecular recognition of antiretroviral drugs.
Saccades move objects of interest into the center of the visual field for high-acuity visual analysis. White, Stritzke, and Gegenfurtner (Current Biology, 18, 124–128, 2008) have shown that saccadic latencies in the context of a structured background are much shorter than those with an unstructured background at equal levels of visibility. This effect has been explained by possible preactivation of the saccadic circuitry whenever a structured background acts as a mask for potential saccade targets. Here, we show that background textures modulate rates of microsaccades during visual fixation. First, after a display change, structured backgrounds induce a stronger decrease of microsaccade rates than do uniform backgrounds. Second, we demonstrate that the occurrence of a microsaccade in a critical time window can delay a subsequent saccadic response. Taken together, our findings suggest that microsaccades contribute to the saccadic facilitation effect, due to a modulation of microsaccade rates by properties of the background.
Das Reckahner Besucherbuch
(2011)
Der Band setzt sich mit Entwicklungen auseinander, die seit der Mitte des 18. Jahrhunderts das Bild der europäischen Aufklärung nachhaltig prägten. Die durch ein eng geknüpftes Kommunikationsnetz miteinander verbundenen Gelehrten und Gebildeten begannen sich für das Volk und dessen Lebensumstände, für Erziehung und Bildung sowie für vielerlei ökonomische Fragen zu interessieren. Dabei begnügten sie sich nicht mehr mit dem gelehrten Diskurs über diese Gegenstände, sondern widmeten sich zugleich auch der Umsetzung ihrer aufklärerischen Reformvorstellungen.
Aufklärung war also weit mehr als eine abgehobene Geistesbewegung. Diese Tatsache wird mit den Beiträgen des vorliegenden Bandes, der die Ergebnisse einer fächer-, grenzen- und sprachenübergreifenden Tagung dokumentiert, erneut unter Beweis gestellt. Die Erfahrung der beteiligten Wissenschaftler besagt allerdings, dass Erkenntnisse, die in der einen Disziplin als gesichert und selbstverständlich gelten, in benachbarten Fachrichtungen noch keineswegs in der genügenden Breite und Intensität rezipiert sein müssen. Die Herausgeber verstehen die hier präsentierten 24 Aufsätze von Verfassern unterschiedlicher Couleur und verschiedener Nationalität deshalb auch als ein nachdrückliches Plädoyer für ein höheres Maß an Interdisziplinarität in den Geisteswissenschaften.
Klausurenkurs im Europarecht
(2011)
Indirect resource competition and interference are widely occurring mechanisms of interspecific interactions. We have studied the seasonal expression of these two interaction types within a two-species, boreal small mammal system. Seasons differ by resource availability, individual breeding state and intraspecific social system. Live-trapping methods were used to monitor space use and reproduction in 14 experimental populations of bank voles Myodes glareolus in large outdoor enclosures with and without a dominant competitor, the field vole Microtus agrestis. We further compared vole behaviour using staged dyadic encounters in neutral arenas in both seasons. Survival of the non-breeding overwintering bank voles was not affected by competition. In the spring, the numbers of male bank voles, but not of females, were reduced significantly in the competition populations. Bank vole home ranges expanded with vole density in the presence of competitors, indicating food limitation. A comparison of behaviour between seasons based on an analysis of similarity revealed an avoidance of costly aggression against opponents, independent of species. Interactions were more aggressive during the summer than during the winter, and heterospecific encounters were more aggressive than conspecific encounters. Based on these results, we suggest that interaction types and their respective mechanisms are not either–or categories and may change over the seasons. During the winter, energy constraints and thermoregulatory needs decrease direct aggression, but food constraints increase indirect resource competition. Direct interference appears in the summer, probably triggered by each individual’s reproductive and hormonal state and the defence of offspring against conspecific and heterospecific intruders. Both interaction forms overlap in the spring, possibly contributing to spring declines in the numbers of subordinate species.
Gewalt, Aggression und Mobbing in der Schule beschäftigen Schulpraxis und Forschung wie auch die Lehrerausbildung an Hochschulen. Die Autoren - mit langjähriger Erfahrung auf dem Gebiet der Gewaltforschung - bilanzieren den Forschungsstand und geben einen Überblick über Programme der Gewaltprävention, die erst im Kontext der Schulentwicklung wirksam werden.
New Public Management
(2011)
New Public Management hat in den vergangenen Jahren die Ansätze und das Verständnis moderner Verwaltungsführung maßgebend beeinflusst.
Stossrichtungen und Grundanliegen dieses Modells wurden zum Teil in die Führungspraxis übernommen und stellen in vielerlei Hinsicht nach wie vor Entwicklungsziele und Leitlinien für die Steuerung und Führung der öffentlichen Verwaltung dar. NPM soll die öffentliche Verwaltung an geforderte Neuausrichtungen anpassen und effizienter gestalten. Ziele und Gestaltung der öffentlichen Verwaltung unter NPM und die dazu notwendigen Instrumente werden in diesem Lehrbuch umfassend und strukturiert erläutert. Besonderes Augenmerk wird dabei auf die Veränderungslinien und -ansätze für die Verwaltungsführung gelegt.
Restoration of semi-natural grassland communities
involves a combination of (1) sward disturbance to
create a temporal window for establishment, and (2)
target species introduction, the latter usually by seed
sowing. With great regularity, particular species
establish only poorly. More reliable establishment
could improve outcome of restoration projects and
increase cost-effectiveness. We investigated the
abiotic germination niche of ten poorly establishing
calcareous grassland species by simultaneously
exploring the effects of moisture and light availability
and temperature fluctuation on percentage germina-
tion and speed of germination. We also investigated
the effects of three different pre-treatments used to
enhance seed germination – cold-stratification, osmo-
tic priming and priming in combination with gibberellic
acid (GA 3 ) – and how these affected abiotic
germination niches. Species varied markedly in width
of abiotic germination niche, ranging from Carex flacca
with very strict abiotic requirements, to several species
reliably germinating across the whole range of abiotic
conditions. Our results suggest pronounced differ-
ences between species in gap requirements for
establishment. Germination was improved in most
species by at least one pre-treatment. Evidence for
positive effects of adding GA 3 to seed priming
solutions was limited. In several species, pre-treated
seeds germinated under a wider range of abiotic
conditions than untreated seeds. Improved knowledge
of species-specific germination niches and the effects
of seed pre-treatments may help to improve species
establishment by sowing, and to identify species for
which sowing at a later stage of restoration or
introduction as small plants may represent a more
viable strategy.
We show that the residue density of the logarithm of a generalized Laplacian on a closed manifold defines an invariant polynomial-valued differential form. We express it in terms of a finite sum of residues of
classical pseudodifferential symbols. In the case of the square of a Dirac operator, these formulas provide a pedestrian proof of the Atiyah–Singer formula for a pure Dirac operator in four dimensions and for a
twisted Dirac operator on a flat space of any dimension. These correspond to special cases of a more general formula by Scott and Zagier. In our approach, which is of perturbative nature, we use either a Campbell–Hausdorff formula derived by Okikiolu or a noncommutative Taylor-type formula.
X-ray observations of young Planetary Nebulæ (PNe) have revealed diffuse emission in extended regions around both H-rich and H-deficient central stars. In order to also repro-duce physical properties of H-deficient objects, we have, at first, extended our time-dependent radiation-hydrodynamic models with heat conduction for such conditions. Here we present some of the important physical concepts, which determine how and when a hot wind-blown bubble forms. In this study we have had to consider the, largely unknown, evolution of the CSPN, the slow (AGB) wind, the fast hot-CSPN wind, and the chemical composition. The main conclusion of our work is that heat conduction is needed to explain X-ray properties of wind-blown bubbles also in H-deficient objects.
We study pattern-forming instabilities in reaction-advection-diffusion systems. We develop an approach based on Lyapunov-Bloch exponents to figure out the impact of a spatially periodic mixing flow on the stability of a spatially homogeneous state. We deal with the flows periodic in space that may have arbitrary time dependence. We propose a discrete in time model, where reaction, advection, and diffusion act as successive operators, and show that a mixing advection can lead to a pattern-forming instability in a two-component system where only one of the species is advected. Physically, this can be explained as crossing a threshold of Turing instability due to effective increase of one of the diffusion constants.
The space missions Voyager and Cassini together with earthbound observations re-vealed a wealth of structures in Saturn’s rings. There are, for example, waves being excited at ring positions which are in orbital resonance with Saturn’s moons. Other structures can be assigned to embedded moons like empty gaps, moon induced wakes or S-shaped propeller features. Further-more, irregular radial structures are observed in the range from 10 meters until kilometers. Here some of these structures will be discussed in the frame of hydrodynamical modeling of Saturn’s dense rings. For this purpose we will characterize the physical properties of the ring particle ensemble by mean field quantities and point to the special behavior of the transport coefficients. We show that unperturbed rings can become unstable and how diffusion acts in the rings. Additionally, the alternative streamline formalism is introduced to describe perturbed regions of dense rings with applications to the wake damping and the dispersion relation of the density waves.
The main thread of this review article is to identify the reasons of how to account for the trajectory of American power in the region. Leaving behind the vast amount of highly politicised and hastily compiled volumes of recent years (notwithstanding valuable exceptions), the monographs composed by Lawrence Freedman, Trita Parsi and Oliver Roy attempt to subtly disentangle the intricacies of US involvement in the region from highly distinct perspectives. One caveat for International Relations theorists is that none of the
aforementioned authors intends to provide theoretical frameworks for his examination. However, since IR theory has damagingly neglected history in the last decades, the works under review here, at least in part, compensate for this disciplinary and intellectual failure. In conclusion, Freedman’s in-depth approach as a diplomatic historian, with its under-lying reference to the various traditions in US foreign policy thinking, is most illuminating, while Parsi’s contestable account focuses too narrowly on the Iran-Israel relationship. Roy’s explications fail to show how and why the ‘ideological’ element in US foreign policy came to carry exceedingly more weight after 2001 than it did in the 1990s.
Increased antioxidant capacity in the plasma of dogs after a single oral dosage of tocotrienols
(2011)
The intestinal absorption of tocotrienols (TCT) in dogs is, to our knowledge, so far unknown. Adult Beagle dogs (n 8) were administered a single oral dosage of a TCT-rich fraction (TRF; 40 mg/kg body weight) containing 32 % a-TCT, 2 % b-TCT, 27 % g-TCT, 14 % d-TCT and 25 % a-tocopherol (a-TCP). Blood was sampled at baseline (fasted), 1, 2, 3, 4, 5, 6, 8 and 12 h after supplementation. Plasma and chylomicron concentrations of TCT and a-TCP were measured at each time point. Plasma TAG were measured enzymatically, and plasma antioxidant capacity was assessed by the Trolox equivalent antioxidant capacity assay. In fasted dogs, levels of TCT were 0·07 ( SD 0·03) mmol/l. Following the administration of the TRF, total plasma TCT peaked at 2 h (7·16 ( SD 3·88) mmol/l; P, 0·01) and remained above baseline levels (0·67 ( SD 0·44) mmol/l; P, 0·01) at 12 h. The TCT response in chylomicrons paralleled the increase in TCT in plasma with a maximum peak (3·49 ( SD 2·06) mmol/l; P, 0·01) at 2 h post-dosage. a-TCP was the major vitamin E detected in plasma and unaffected by TRF supplementation. The Trolox equivalent values increased from 2 h (776 ( SD 51·2) mmol/l) to a maximum at 12 h (1130 ( SD 7·72) mmol/l; P,0·01). The results show that TCT are detected in postprandial plasma of dogs. The increase in antioxidant capacity suggests a potential beneficial role of TCT supplementation in the prevention or treatment of several diseases in dogs.
We asked whether invariant phonetic indices for syllable structure can be identified in a language where word-initial consonant clusters, regardless of their sonority profile, are claimed to be parsed heterosyllabically. Four speakers of Moroccan Arabic were recorded, using Electromagnetic Articulography. Pursuing previous work, we employed temporal diagnostics for syllable structure, consisting of static correspondences between any given phonological organisation and its presumed phonetic indices. We show that such correspondences offer only a partial understanding of the relation between syllabic organisation and continuous indices of that organisation. We analyse the failure of the diagnostics and put forth a new approach in which different phonological organisations prescribe different ways in which phonetic indices change as phonetic parameters are scaled. The main finding is that invariance is found in these patterns of change, rather than in static correspondences between phonological constructs and fixed values for their phonetic indices.
Although horses and donkeys belong to the same genus, their genetic characteristics probably result in specific proteomes and post-translational modifications (PTM) of proteins. Since PTM can alter protein properties, specific PTM may contribute to species-specific characteristics. Therefore, the aim of the present study was to analyse differences in serum protein profiles of horses and donkeys as well as mules, which combine the genetic backgrounds of both species. Additionally, changes in PTM of the protein transthyretin (TTR) were analysed. Serum protein profiles of each species (five animals per species) were determined using strong anion exchanger ProteinChips (R) (Bio-Rad, Munich, Germany) in combination with surface-enhanced laser desorption ionisation-time of flight MS. The PTM of TTR were analysed subsequently by immunoprecipitation in combination with matrix-assisted laser desorption ionisation-time of flight MS. Protein profiling revealed species-specific differences in the proteome, with some protein peaks present in all three species as well as protein peaks that were unique for donkeys and mules, horses and mules or for horses alone. The molecular weight of TTR of horses and donkeys differed by 30Da, and both species revealed several modified forms of TTR besides the native form. The mass spectra of mules represented a merging of TTR spectra of horses and donkeys. In summary, the present study indicated that there are substantial differences in the proteome of horses and donkeys. Additionally, the results probably indicate that the proteome of mules reveal a higher similarity to donkeys than to horses.
Using the notion of an elementary loop, Gebser and Schaub (2005. Proceedings of the Eighth International Conference on Logic Programming and Nonmonotonic Reasoning (LPNMR’05 ), 53–65) refined the theorem on loop formulas attributable to Lin and Zhao (2004) by considering loop formulas of elementary loops only. In this paper, we reformulate the definition of an elementary loop, extend it to disjunctive programs, and study several properties of elementary loops, including how maximal elementary loops are related to minimal unfounded sets. The results provide useful insights into the stable model semantics in terms of elementary loops. For a nondisjunctive program, using a graph-theoretic characterization of an elementary loop, we show that the problem of recognizing an elementary loop is tractable. On the other hand, we also show that the corresponding problem is coNP-complete for a disjunctive program. Based on the notion of an elementary loop, we present the class of Head-Elementary-loop-Free (HEF) programs, which strictly generalizes the class of Head-Cycle-Free (HCF) programs attributable to Ben-Eliyahu and Dechter (1994. Annals of Mathematics and Artificial Intelligence 12, 53–87). Like an HCF program, an HEF program can be turned into an equivalent nondisjunctive program in polynomial time by shifting head atoms into the body.
We present XMM-Newton and Chandra observations of the born-again planetary nebula A 30. These X-ray observations reveal a bright unresolved source at the position of the central star whose X-ray luminosity exceeds by far the model expectations for photospheric emission and for shocks within the stellar wind. We suggest that a “born-again hot bubble” may be responsible for this X-ray emission. Diffuse X-ray emission associated with the petal-like features and one of the H-poor knots seen in the optical is also found. The weakened emission of carbon lines in the spectrum of the diffuse emission can be interpreted as the dilution of stellar wind by mass-loading or as the detection of material ejected during a very late thermal pulse.
Zwischen Heterogenität und Hierarchie in der Bildung - Studien zur Unvollendbarkeit der Demokratie
(2011)
We introduce an approach to detecting inconsistencies in large biological networks by using answer set programming. To this end, we build upon a recently proposed notion of consistency between biochemical/genetic reactions and high-throughput profiles of cell activity. We then present an approach based on answer set programming to check the consistency of large-scale data sets. Moreover, we extend this methodology to provide explanations for inconsistencies by determining minimal representations of conflicts. In practice, this can be used to identify unreliable data or to indicate missing reactions.
Building biological models by inferring functional dependencies from experimental data is an important issue in Molecular Biology. To relieve the biologist from this traditionally manual process, various approaches have been proposed to increase the degree of automation. However, available approaches often yield a single model only, rely on specific assumptions, and/or use dedicated, heuristic algorithms that are intolerant to changing circumstances or requirements in the view of the rapid progress made in Biotechnology. Our aim is to provide a declarative solution to the problem by appeal to Answer Set Programming (ASP) overcoming these difficulties. We build upon an existing approach to Automatic Network Reconstruction proposed by part of the authors. This approach has firm mathematical foundations and is well suited for ASP due to its combinatorial flavor providing a characterization of all models explaining a set of experiments. The usage of ASP has several benefits over the existing heuristic algorithms. First, it is declarative and thus transparent for biological experts. Second, it is elaboration tolerant and thus allows for an easy exploration and incorporation of biological constraints. Third, it allows for exploring the entire space of possible models. Finally, our approach offers an excellent performance, matching existing, special-purpose systems.
Preference handling and optimization are indispensable means for addressing nontrivial applications in Answer Set Programming (ASP). However, their implementation becomes difficult whenever they bring about a significant increase in computational complexity. As a consequence, existing ASP systems do not offer complex optimization capacities, supporting, for instance, inclusion-based minimization or Pareto efficiency. Rather, such complex criteria are typically addressed by resorting to dedicated modeling techniques, like saturation. Unlike the ease of common ASP modeling, however, these techniques are rather involved and hardly usable by ASP laymen. We address this problem by developing a general implementation technique by means of meta-prpogramming, thus reusing existing ASP systems to capture various forms of qualitative preferences among answer sets. In this way, complex preferences and optimization capacities become readily available for ASP applications.
The armed conflict in Afghanistan since 2001 has raised manifold questions pertaining to the humanitarian rules relative to the conduct of hostilities. In Afghanistan, as is often the case in so-called asymmetric conflicts, the geographical and temporal boundaries of the battlefield, and the distinction between civilians and fighters, are increasingly blurred. As a result, the risks for both civilians and soldiers operating in Afghanistan are high. The objective of this article is to assess whether - and if so how much - the armed conflict in Afghanistan has affected the application and interpretation of the principles of distinction, proportionality, and precaution - principles that form the core of legal rules pertaining to the conduct of hostilities.
Urbanity and literature
(2011)
Transarea studies focus upon spaces as created by the movements that criss-cross them. From this point of view, from its very beginnings, literature is closely interrelated with a vectorial (and much less with a purely spatial) conception of history - and with urbanity, which plays a decisive role in Gilgamesh's travels through a (narrative) cosmos centered upon the city of Uruk. This article explores the city as a transareal space of movement in three examples of literature, with no fixed abode, around the turn of the millennium, i.e. Assia Djebar's Les Nuits de Strasbourg, Emine Sevgi Oezdamar's Istanbul-Berlin Trilogy, and Cecile Wajsbrot's L'ile aux musees. These three writers project, in a very specific way, cities in motion as anagrammatic and fractal structures.
To understand the evolution and morphology of planetary nebulae, a detailed knowledge of their central stars is required. Central stars that exhibit emission lines in their spectra, indicating stellar mass-loss allow to study the evolution of planetary nebulae in action. Emission line central stars constitute about 10 % of all central stars. Half of them are practically hydrogen-free Wolf-Rayet type central stars of the carbon sequence, [WC], that show strong emission lines of carbon and oxygen in their spectra. In this contribution we address the weak emission-lines central stars (wels). These stars are poorly analyzed and their hydrogen content is mostly unknown. We obtained optical spectra, that include the important Balmer lines of hydrogen, for four weak emission line central stars. We present the results of our analysis, provide spectral classification and discuss possible explanations for their formation and evolution.
Der Bürger entscheidet mit
(2011)
»Warum erregt der geplante Abriss eines Bahnhofs die Nation, während gegen das hundertfache Sterben von Bibliotheken immer nur ein paar Stimmen laut werden? Wo sind die Wutbürger, wenn man sie braucht?«, überlegte sich hierzulande Tilman Spreckelsen.1 Die Kernfrage lautet also: Stehen die Bürger eigentlich hinter der Bibliothek? Ob und wie die Bürgerschaft für ihre Öffentliche Bibliothek entscheidet, wenn sie entscheiden darf, wird im vorliegenden Aufsatz thematisiert. Ergebnisse von Bürgerbegehren und Bürgerentscheiden stehen dabei im Fokus, da bürgerschaftliches Engagement bei diesen Mitwirkungsinstrumenten besonders gefragt ist und es gleichzeitig kommunalpolitische Folgen haben kann. Am Beispiel von Stuttgart 21 wird darüber hinaus der Fragestellung nachgegangen, wie sich eine Öffentliche Bibliothek zu Sachverhalten positioniert, die (nicht nur) kommunalpolitisch brisant sind.
Mehr Chancen als Risiken
(2011)
Anne Christensen spricht von partizipativer Entwicklung, wenn sie sich zum Komplex Bibliothek 2.0 äußert, und meint damit primär die stärkere Einbeziehung der Benutzer, wenn es um die Zukunft der kollaborativen Erschließung von Medien in Bibliothekskatalogen geht.1 Diese Art der Partizipation tangiert Kernaufgaben sowohl an Öffentlichen als auch an wissenschaftlichen Bibliotheken. Über die Beteiligung der Benutzer am Katalog 2.0 hinaus könnte auch durch eine weitere Form der Partizipation Einfl uss auf die Zukunft Öffentlicher Bibliotheken genommen werden: durch den Bürgerhaushalt.
Basiswissen BWL – prägnant und verständlich vermittelt. Das Lehrbuch vermittelt Wirtschaftswissenschaftlern, angehenden Wirtschaftsingenieuren und -informatikern sowie Nebenfachstudierenden aus dem technischen Bereich die wichtigsten Grundlagen der BWL. Die 6. Auflage wurde umfassend überarbeitet, an die aktuelle Gesetzeslage angepasst und inhaltlich erweitert. Lernziele, Beispiele, Kontrollfragen und Aufgaben inklusive Lösungen erleichtern das selbstständige Lernen. Das optimierte Layout sorgt für mehr Übersichtlichkeit.
Mindfulness and acceptance describe the skills necessary to experience emotions and thoughts (e.g., performance-interfering cognitions) consciously and without judging them. This article introduces the mindfulness and acceptance approach and its potential in the context of competitive sports. Definitions as well as research results related to mechanisms of action and differential psychological aspects are given and the efficacy of the approach in the field of clinical psychology is reviewed. The rationale and implementation of the mindfulness-acceptance-commitment approach, an approach adapted for performance enhancement, is illustrated. Finally, evidence from psychotherapy research is presented, and a recommendation for the use of mindfulness and acceptance in the context of competitive sports is given.
Spielberger's (1972) Trait-State-Anxiety theory distinguishes between anxiety as a trait (A-trait) - involving a stable characteristic of a person to react with anxiety in response to varying situations and anxiety as a state (A-state), a situation-dependent reaction to a stimulus perceived as threatening. Using a general instead of a sport-specific measure, a previous study provided only mixed support for core predictions of the theory as related to sports (Schwenkmezger, 1985). With the aid of enhanced instruments and statistical methods, we tested these predictions again. The multidimensional and competition-specific assessment of anxiety results in support for the assumption of a stable A-trait and a fluctuating A-state, whereby the A-trait not only predicts the intensity of A-states but also the A-state variability. The repeated assessment of A-states prior to two competitions reveals a rather low relative consistency (i.e., interindividual differences across measurements were only moderately stable). Especially this latter finding suggests that, in order to gain a full understanding of the experience of competitive anxiety in athletes, sport psychologists should not only assess competitive A-traits, but also repeatedly measure competitive A-states.
The present article analyzes the socio-economic background of maths teachers in Germany and its relation to career-related decisions and job-related convictions. These analyzes is based on data collected through questionnaires answered by 1126 maths teachers working at a sample of secondary schools representative of Germany. Following Bourdieu's theory, the authors examine whether the economic and cultural conditions prevailing in the teachers' families of origin are related to their decision to pursue this specific professional career or to their job-related convictions. Furthermore, it is analyzed in how far teachers, in their everyday work in the classroom, meet students from groups of origin foreign to the teachers themselves. The results show that the teachers, socio-economic background has no systematic relation to either their career-related decisions or their job-related convictions.
The present study examines whether the use of different frequency scales in questionnaires about physical activity influences respondents' own estimation of their activity, as well as subsequent measurements of health- und sport-related cognitions and evaluations. Using a randomized research design we recruited a sample of 118 participants. One group received a high frequency scale for assessing their exercise frequency with the response categories "never", "less often", "once a month", "once a week", or "most days." The other group answered with a medium frequency scale with the alternatives "never", "less often", " once every few months", "once a month", and " once a week or more often." As dependent variables all participants judged the subjective importance of physical activity and their health-related quality of life (WHO-QOL-bref). Results indicate the expected response errors, owing to the fact that using a high-frequency scale produces higher levels of self-reported physical activity (Cramer's V = .30). Corresponding to this the subjective importance of physical activity increased (d = .37) and the health-related quality of life was judged to be better (d = .36). Such artefacts might be eliminated by using standardized formulations such as "I exercise... times per week/month for... minutes."
Signals from the past forms and functions of the traditional behavior in Thomas Kling's essay
(2011)
The link between pornography use, normative acceptance of sexual aggression, and the presence of risk factors of sexual aggression in sexual scripts for consensual sexual interactions was studied in a sample of 197 adolescents in Germany. Risk factors included sex after only a short acquaintanceship, alcohol and drug use in sexual interactions, and ambiguous communication of sexual intentions. In addition to a measure of overall pornography use, exposure to portrayals of consensual sex, coerced sex and degrading sex was measured. Almost all participants had seen pornografic material at least once, just under half had seen depictions of coerced sex. Significant correlations were found between all measures of pornography use and the presence of risk factors of sexual aggression in consensual sexual scripts. Violent pornography usage showed a positive correlation with the normative acceptance of sexual aggression that was partly accounted for by sexual scripts. The findings are discussed with regard to the significance of pornografic media contents in the process of adolescents' sexual socialization.
Prospero's America: John Winthrop, Jr., Alchemy, and the Creation of New England Culture, 1606-1676
(2011)
Previous studies on the electoral fortunes of extreme right parties (ERPs) have pointed to the importance of variables of party competition for the success - or failure - of ERPs. These studies vary greatly when it comes to describing the political opportunity structure of the extreme right. Apart from their methodological differences, existing studies differ especially with regard to the assumed underlying dimension of party competition. This article tests the impact of three frequently discussed variables in the political opportunity structure of ERPs (mainstream party convergence, position of the established right and party system polarisation) on the vote share of ERPs in Western Europe. In addition to examining previous studies in this field, it focuses on the interplay between the economic and the cultural dimensions as part of the political opportunity structure. The authors show that a decrease in polarisation with regard to economic questions is accompanied by a growing salience of ERPs' core issues, leading in the end to an increase in ERPs' vote share.
The Karaburun Peninsula, which is considered part of the Anatolide-Tauride Block of Turkey, contains clastic and carbonate sequences deposited on the northern margin of Gondwana. The Palaeozoic clastic sequence, which is intruded by the Early Triassic granitoid and tectonically overlies a Mesozoic melange sequence, can be divided into three subunits: a lower clastic subunit consisting of a sandstone-shale alternation, an upper clastic subunit consisting of black chert-bearing shales, sandstone and conglomerate, and a Permo-Carboniferous carbonate subunit. The lower Triassic Karaburun I-type granitoid has a high initial Sr-87/Sr-86 ratio (0.709021-0.709168), and low Nd-143/Nd-144 ratio (0.512004-0.512023) and epsilon Nd (-5.34 to -5.70) isotopic values. Geochronological data indicate a crystallization (intrusion) age of 247.1 +/- 2.0 Ma (Scythian). Geochemically, the acidic magmatism reflects a subduction-related continental-arc basin tectonic setting, which can be linked to the opening of the northern branch of Neo-Tethys as a continental back-arc rifting basin on the northern margin of Gondwana. This can be related to the closure through southward subduction of the Palaeotethys Ocean beneath Gondwana.
Cross-coupling reactions, such as Buchwald-Hartwig arylamination and direct intramolecular biaryl coupling by C-H activation, were carried out using various Palladium-N-heterocyclic carbenes (Pd-NHC) as catalysts. The yields were good to excellent. The latter strategy was adopted to transform two dibenzylbutane lignans, isolated from the leaves of Ocotea macrophylla (Lauraceae), into the corresponding dibenzocyclooctane lignans in good overall yields. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications (R) to view the free supplemental file.
Random matrix theory (RMT) is well suited to describing the emergent properties of systems with complex interactions amongst their constituents through their eigenvalue spectrums. Some RMT results are applied to the problem of clustering high dimensional biological data with complex dependence structure amongst the variables. It will be shown that a gene relevance or correlation network can be constructed by choosing a correlation threshold in a principled way, such that it corresponds to a block diagonal structure in the correlation matrix, if such a structure exists. The structure is then found using community detection algorithms, but with parameter choice guided by RMT predictions. The resulting clustering is compared to a variety of hierarchical clustering outputs and is found to the most generalised result, in that it captures all the features found by the other considered methods.
Phase behaviour and the mesoscopic structure of zwitanionic surfactant mixtures based on the zwitterionic tetradecyldimethylamine oxide (TDMAO) and anionic lithium perfluoroalkyl carboxylates have been investigated for various chain lengths of the perfluoro surfactant with an emphasis on spontaneously forming vesicles. These mixtures were studied at a constant total concentration of 50 mM and characterised by means of dynamic light scattering (DLS), electric conductivity, small-angle neutron scattering (SANS), viscosity, and cryo-scanning electron microscopy (Cryo-SEM). No vesicles are formed for relatively short perfluoro surfactants. The extension of the vesicle phase becomes substantially larger with increasing chain length of the perfluoro surfactant, while at the same time the size of these vesicles increases. Head group interactions in these systems play a central role in the ability to form vesicles, as already protonating 10 mol% of the TDMAO largely enhances the propensity for vesicle formation. The range of vesicle formation in the phase diagram is not only substantially enlarged but also extends to shorter perfluoro surfactants, where without protonation no vesicles would be formed. The size and polydispersity of the vesicles are related to the chain length of the perfluoro surfactant, the vesicles becoming smaller and more monodisperse with increasing perfluoro surfactant chain length. The ability of the mixed systems to form well-defined unilamellar vesicles accordingly can be controlled by the length of the alkyl chain of the perfluorinated surfactant and depends strongly on the charge conditions, which can be tuned easily by pH-variation.
Diffusion in a series of ionic liquids is investigated by a combination of Broadband Dielectric Spectroscopy (BDS) and Pulsed Field Gradient Nuclear Magnetic Resonance (PFG NMR). It is demonstrated that the mean jump lengths increase with the molecular volumes determined from quantum-chemical calculations. This provides a direct means-via Einstein-Smoluchowski relation-to determine the diffusion coefficient by BDS over more than 8 decades unambiguously and in quantitative agreement with PFG NMR measurements. New possibilities in the study of charge transport and dynamic glass transition in ionic liquids are thus opened.
A set of double thermoresponsive diblock copolymers poly(N-n-propylacrylamide)-block-poly(N-ethylacrylamide) (PNPAM-b-PNEAM) was synthesised by sequential reversible addition-fragmentation chain transfer (RAFT) polymerisations. Using a twofold trimethylsilyl (TMS)-labeled RAFT-agent, the relative size of the two blocks was varied. While soluble as unimers below 15 degrees C, all copolymers exhibited thermally induced two-step self-assembly in water, due to distinct lower critical solution temperature (LCST) phase transitions of PNPAM (around 20 degrees C) and PNEAM (around 70 degrees C). Their temperature-dependent self-organisation in dilute aqueous solution was studied by turbidimetry, dynamic light scattering, transmission electron microscopy, and (1)H NMR spectroscopy. The copolymers show distinct, two-step self-organisation behaviour with respect to transition temperatures, aggregate type and size, which can be correlated to the relative lengths of the low and high LCST blocks. For polymers having short blocks with low LCST, the first thermal transition induces the formation of individual micelles. Further heating above the second thermal transition results reversibly either in a shrink of the micelle size or in aggregation of the micelles, with hydrodynamic diameters below 250 nm. In contrast in the case of polymers having a long block with low LCST, the first thermal transition already leads to clusters of micelles, while the second thermal transition makes the clusters shrink. Noteworthy, the twofold TMS-labeled end groups report not only on the molar masses of the polymers, but can simultaneously serve as NMR-probes for the self-assembly process. The signal of the TMS-aryl end group displays a reversible temperature dependent, two-step splitting that is indicative of the self-organisation of the block copolymers.
Soft, physically crosslinking, block copolymer elastomers were filled with surface-treated nanoparticles, in order to evaluate the possibility for improvement of their properties when used as soft dielectric actuators. The nanoparticles led to improvements in dielectric properties, however they also reinforced the elastomer matrix. Comparing dielectric spectra of composites with untreated and surface-treated particles showed a measurable influence of the surface on the dielectric loss behaviour for high filler amounts, strongly indicating an improved host-guest interaction for the surface-treated particles. Breakdown strength was measured using a test bench and was found to be in good agreement with the results from the actuation measurements. Actuation responses predicted by a model for prestrained actuators agreed well with measurements up to a filler amount of 20%(vol). Strong improvements in actuation behaviour were observed, with an optimum near 15%(vol) nanoparticles, corresponding to a reduction in electrical field of 27% for identical actuation strains. The use of physically crosslinking elastomer ensured the mechanical properties of the matrix elastomer were unchanged by nanoparticles effecting the crosslinking reaction, contrary to similar experiments performed with chemically crosslinking elastomers. This allows for a firm conclusion about the positive effects of surface-treated nanoparticles on actuation behavior.
Self-assembly phenomena in block copolymer systems are attracting considerable interest from the scientific community and industry alike. Particularly interesting is the behavior of amphiphilic copolymers, which can self-organize into nanoscale-sized objects such as micelles, vesicles, or tubes in solution, and which form well-defined assemblies at interfaces such as air-liquid, air-solid, or liquid-solid. Depending on the polymer chemistry and architecture, various types of organization at interfaces can be expected, and further exploited for applications in nanotechnology, electronics, and biomedical sciences.
In this article, we discuss the formation and characterization of Langmuir monolayers from various amphiphilic block copolymers, including chargeable and thus pH-responsivematerials. Solid-supported polymer films are reviewed in the context of alteration of surface properties by ultrathin polymer layers and the possibilities for application in tissue engineering, sensors and biomaterials. Finally, we focus on how organic and polymer monolayers influence the growth of inorganic materials. This is a truly biomimetic approach since Nature uses soft interfaces to control the nucleation, growth, and morphology of biominerals such as calcium phosphate, calcium carbonate, and silica.
The formation of secondary Ln(III) solid phases (e.g. Nd(OH)CO3 and Sm(OH)CO3) has been studied as a function of the humic acid (HA) concentration in 0.1 M NaClO4 aqueous solution and their solubility has been investigated in the neutral pH range (6.5-8) under normal atmospheric conditions. Nd(III) and Sm(III) were selected as analogues for trivalent lanthanide and actinide ions. The solid phases under investigation have been prepared by alkaline precipitation and characterized by TGA, ATR-FTIR, XRD, TRLFS, DR-UV-Vis and Raman spectroscopy, and solubility measurements. The spectroscopic data obtained indicate that Nd(OH)CO3 and Sm(OH)CO3 are stable and remain the solubility limiting solid phases even in the presence of increased HA concentration (0.5 g/L) in solution. Upon base addition in the Ln(III)-HA system decomplexation of the previously formed Ln(III)-humate complexes and precipitation of two distinct phases occurs, the inorganic (Ln(OH)CO3) and the organic phase (HA), which is adsorbed on the particle surface of the former. Nevertheless, HA affects the particle size of the solid phases. Increasing HA concentration results in decreasing crystallite size of the Nd(OH)CO3 and increasing crystallite size of the Sm(OH)CO3 solid phase, and affects inversely the solubility of the solid phases. However, this impact on the solid phase properties is expected to be of minor relevance regarding the chemical behavior and migration of trivalent lanthanides and actinides in the geosphere.
A sediment core from a closed basin lake (Lake Kuhai) from the semi-arid northeastern Tibetan Plateau was analysed for its pollen record to infer Lateglacial and post glacial vegetation and climatic change. At Lake Kuhai five major vegetation and climate shifts could be identified: (1) a change from cold and dry to relatively warmer and more moist conditions at 14.8 cal ka BP: (2) a shift to conditions of higher effective moisture and a stepwise warmer climate at 13.6 cal ka BP; (3) a further shift with increased moisture but colder conditions at 7.0 cal ka BP; (4) a return to a significantly colder and drier phase at 6.3 cal ka BP; (5) and a change back to relatively moist conditions at 2.2 cal ka BP. To investigate the response of lake ecosystems to climatic changes, statistical comparisons were made between the lake Kuhai pollen record and a formerly published ostracod and sedimentary record from the same sediment core. Furthermore, the pollen and lacustrine proxies from lake Kuhai were compared to a previously published pollen and lacustrine record from the nearby Lake Koucha. Statistical comparisons were done using non-metric multidimensional scaling and Procrustes rotation. Differences between lacustrine and pollen responses within one site could be identified, suggesting that lacustrine proxies are partly influenced by in-lake or local catchment processes, whereas the terrestrial (pollen) proxy shows a regional climate signal. Furthermore, we found regional differences in proxy response between lake Kuhai and Lake Koucha. Both pollen records reacted in similar ways to major environmental changes, with minor differences in the timing and magnitude of these changes. The lacustrine records were very similar in their timing and magnitude of response to environmental changes; however, the nature of change was at times very distinct. To place the current study in the context of Holocene moisture evolution across the Tibetan Plateau, we applied a five-scale moisture index and average link clustering to all available continuous palaeo-climate records from the Tibetan Plateau to possibly find general patterns of moisture evolution on the Plateau. However, no common regional pattern of moisture evolution during the Holocene could be detected. We assign this to complex responses of different proxies to environmental and atmospheric changes in an already very heterogeneous mountain landscape where minor differences in elevation can cause strong variation in microenvironments.
Can you see me in the snow? - action simulation aids the detection of visually degraded human motion
(2011)
Using a novel paradigm, we demonstrate that action simulation can directly facilitate ongoing perception of people's movements. Point-light actors (PLAs) representing common human motions were shown embedded in a visual noise reminiscent of "TV snow". At first, the PLAs were perceived clearly, then occluded from view for a short duration, during which it was hypothesized that a real-time action simulation was generated tracking the motion's course. The PLA then reappeared in motion at variable visibility against the noise, whilst detection thresholds for the reappearance were measured. In the crucial manipulation, the test motion was either temporally congruent with the motion as it would have continued during occlusion, and thus temporally matching the simulation, or temporally incongruent. Detection thresholds were lower for congruent than for incongruent reappearing motions, suggesting that reappearing motion that temporally matched the internal action simulation was more likely to be detected.
The lexical database dlexDB supplies in form of an online database frequency-based norms of numerous process-related word properties for psychological and linguistic research. These values include well known variables such as printed frequency of word form and lemma as documented also in CELEX (Baayen, Piepenbrock und Gulikers, 1995). In addition, we compute new values like frequencies based on syllables, and morphemes as well as frequencies of character chains, and multiple word combinations. The statistics are based on the Kernkorpus des Digitalen Wrterbuchs der deutschen Sprache (DWDS) with over 100 million running words. We illustrate the validity of these norms with new results about fixation durations in sentence reading.
The present study investigates diagnostic skills of German teachers in estimating basic reading capacities of sixth graders and the way they relate to achievement heterogeneity of the judged student group and to students' language background.
The data were obtained from a sample of 39 German teachers and their classes in the context of the Berlin Longitudinal Reading Study. Judgements on different levels were analysed (achievement of sixth graders in general and of individual students). Diagnostic skills were investigated using different indicators: the personal judgement error and tendency and the accuracy in identifying achievement differences between individual students (rank component). The accuracy in estimating reading capacities of students with and without a different language background was investigated by means of achievement level matched pairs.
The outcomes indicated, among others, an overestimation of students' general achievement level and on average an acceptable accuracy in identifying achievement differences between individual students. They showed equal difficulties in judging performances of students with and without a different language background.
Yeast hexokinase isoenzyme ScHxk2 stability of a two-domain protein with discontinuous domains
(2011)
The hexokinase isoenzyme 2 of Saccharomyces cerevisiae (ScHxk2) represents an archetype of a two-domain protein with the active site located in a cleft between the two domains. Binding of the substrate glucose results in a rigid body movement of the two domains leading to a cleft closure of the active site. Both domains of this enzyme are composed of discontinuous peptide sequences. This structural feature is reflected in the stability and folding of the ScHxk2 protein. Structural transitions induced by urea treatment resulted in the population of a thermodynamically stable folding intermediate, which, however, does not correspond to a molecule with one domain folded and the other unfolded. As demonstrated by different spectroscopic techniques, both domains are structurally affected by the partial denaturation. The intermediate possesses only 40% of the native secondary structural content and a substantial increase in the Stokes radius as judged by circular dichroism and dynamic light scattering analyses. One-dimensional H-1 NMR data prove that all tryptophan residues are in a non-native environment in the intermediate, indicating substantial changes in the tertiary structure. Still, the intermediate possesses quite a high stability for a transition intermediate of about Delta G = -22 kJ mol(-1).
Efficacy of Psychotherapy with Children and Adolescents
Psychotherapeutic interventions require empirical as well as scientific assessment. Specifically, the proven efficacy of psychotherapy for children and adolescents is essential. Thus, studies examining treatment efficacy and meta-analyses are necessary to compare effect sizes of individual therapeutic interventions between treatment groups and waiting control groups. Assessment of 138 primary studies from 1993-2009 documented the efficacy of psychotherapy for children and adolescents. Furthermore, behavioural therapy outperformed non-behavioural interventions, as 90 % of behavioural interventions showed larger effect sizes compared to non-behavioural psychotherapy. Analysis of moderator variables demonstrated an improved treatment efficacy for individual therapy, inclusion of the family, treatment of internalised disorders, and in clinical samples. Stability of psychotherapeutic treatment effects over time was demonstrated.
As part of the POPS study (Potsdam prevention of eating disorders) 300 adolescents aged between 10 and 13 years completed questionnaires measuring satisfaction with weight and muscles, body change strategies and disturbed eating behavior. More than half of the girls and a third of the boys are dissatisfied with their weight. Nearly 70% of the male participants were unhappy with their muscles. Both forms of body dissatisfaction are influenced by similar sociocultural and psychological factors. While weight dissatisfaction leads to weight reduction strategies and disturbed eating, muscle dissatisfaction results in muscle enhancement methods. Potential harmful consequences of excessive muscle building techniques are discussed. The data emphasize the need for a sex-specific investigation of body dissatisfaction and its consequences. Body image aspects relevant to boys should be added to intervention and prevention approaches.