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Background: Neuroenhancement (NE), the use of psychoactive substances in order to enhance a healthy individual's cognitive functioning from a proficient to an even higher level, is prevalent in student populations. According to the strength model of self-control, people fail to self-regulate and fall back on their dominant behavioral response when finite self-control resources are depleted. An experiment was conducted to test the hypothesis that ego-depletion will prevent students who are unfamiliar with NE from trying it.
Findings: 130 undergraduates, who denied having tried NE before (43% female, mean age = 22.76 +/- 4.15 years old), were randomly assigned to either an ego-depletion or a control condition. The dependent variable was taking an "energy-stick" (a legal nutritional supplement, containing low doses of caffeine, taurine and vitamin B), offered as a potential means of enhancing performance on the bogus concentration task that followed. Logistic regression analysis showed that ego-depleted participants were three times less likely to take the substance, OR = 0.37, p = .01.
Conclusion: This experiment found that trying NE for the first time was more likely if an individual's cognitive capacities were not depleted. This means that mental exhaustion is not predictive for NE in students for whom NE is not the dominant response. Trying NE for the first time is therefore more likely to occur as a thoughtful attempt at self-regulation than as an automatic behavioral response in stressful situations. We therefore recommend targeting interventions at this inter-individual difference. Students without previous reinforcing NE experience should be provided with information about the possible negative health outcomes of NE. Reconfiguring structural aspects in the academic environment (e.g. lessening workloads) might help to deter current users.
Background: Short lived, iteroparous animals in seasonal environments experience variable social and environmental conditions over their lifetime. Animals can be divided into those with a "young-of-the-year" life history (YY, reproducing and dying in the summer of birth) and an "overwinter" life history (OW, overwintering in a subadult state before reproducing next spring).
We investigated how behavioural patterns across the population were affected by season and sex, and whether variation in behaviour reflects the variation in life history patterns of each season. Applications of pace-of-life (POL) theory would suggest that long-lived OW animals are shyer in order to increase survival, and YY are bolder in order to increase reproduction. Therefore, we expected that in winter and spring samples, when only OW can be sampled, the animals should be shyer than in summer and autumn, when both OW and YY animals can be sampled. We studied common vole (Microtus arvalis) populations, which express typical, intra-annual density fluctuation. We captured a total of 492 voles at different months over 3 years and examined boldness and activity level with two standardised behavioural experiments.
Results: Behavioural variables of the two tests were correlated with each other. Boldness, measured as short latencies in both tests, was extremely high in spring compared to other seasons. Activity level was highest in spring and summer, and higher in males than in females.
Conclusion: Being bold in laboratory tests may translate into higher risk-taking in nature by being more mobile while seeking out partners or valuable territories. Possible explanations include asset-protection, with OW animals being rather old with low residual reproductive value in spring. Therefore, OW may take higher risks during this season. Offspring born in spring encounter a lower population density and may have higher reproductive value than offspring of later cohorts. A constant connection between life history and animal personality, as suggested by the POL theory, however, was not found. Nevertheless, correlations of traits suggest the existence of animal personalities. In conclusion, complex patterns of population dynamics, seasonal variation in life histories, and variability of behaviour due to asset-protection may cause complex seasonal behavioural dynamics in a population.
Background: Adaptive behavioural strategies promoting co-occurrence of competing species are known to result from a sympatric evolutionary past. Strategies should be different for indirect resource competition (exploitation, e.g., foraging and avoidance behaviour) than for direct interspecific interference (e.g., aggression, vigilance, and nest guarding). We studied the effects of resource competition and nest predation in sympatric small mammal species using semi-fossorial voles and shrews, which prey on vole offspring during their sensitive nestling phase. Experiments were conducted in caged outdoor enclosures. Focus common vole mothers (Microtus arvalis) were either caged with a greater white-toothed shrew (Crocidura russula) as a potential nest predator, with an herbivorous field vole (Microtus agrestis) as a heterospecific resource competitor, or with a conspecific resource competitor.
Results: We studied behavioural adaptations of vole mothers during pregnancy, parturition, and early lactation, specifically modifications of the burrow architecture and activity at burrow entrances. Further, we measured pre- and postpartum faecal corticosterone metabolites (FCMs) of mothers to test for elevated stress hormone levels. Only in the presence of the nest predator were prepartum FCMs elevated, but we found no loss of vole nestlings and no differences in nestling body weight in the presence of the nest predator or the heterospecific resource competitor. Although the presence of both the shrew and the field vole induced prepartum modifications to the burrow architecture, only nest predators caused an increase in vigilance time at burrow entrances during the sensitive nestling phase.
Conclusion: Voles displayed an adequate behavioural response for both resource competitors and nest predators. They modified burrow architecture to improve nest guarding and increased their vigilance at burrow entrances to enhance offspring survival chances. Our study revealed differential behavioural adaptations to resource competitors and nest predators.
Movement of organisms is one of the key mechanisms shaping biodiversity, e.g. the distribution of genes, individuals and species in space and time. Recent technological and conceptual advances have improved our ability to assess the causes and consequences of individual movement, and led to the emergence of the new field of ‘movement ecology’. Here, we outline how movement ecology can contribute to the broad field of biodiversity research, i.e. the study of processes and patterns of life among and across different scales, from genes to ecosystems, and we propose a conceptual framework linking these hitherto largely separated fields of research. Our framework builds on the concept of movement ecology for individuals, and demonstrates its importance for linking individual organismal movement with biodiversity. First, organismal movements can provide ‘mobile links’ between habitats or ecosystems, thereby connecting resources, genes, and processes among otherwise separate locations. Understanding these mobile links and their impact on biodiversity will be facilitated by movement ecology, because mobile links can be created by different modes of movement (i.e., foraging, dispersal, migration) that relate to different spatiotemporal scales and have differential effects on biodiversity. Second, organismal movements can also mediate coexistence in communities, through ‘equalizing’ and ‘stabilizing’ mechanisms. This novel integrated framework provides a conceptual starting point for a better understanding of biodiversity dynamics in light of individual movement and space-use behavior across spatiotemporal scales. By illustrating this framework with examples, we argue that the integration of movement ecology and biodiversity research will also enhance our ability to conserve diversity at the genetic, species, and ecosystem levels.
Background
Appearance-related social pressure plays an important role in the development of a negative body image and self-esteem as well as severe mental disorders during adolescence (e.g. eating disorders, depression). Identifying who is particularly affected by social pressure can improve targeted prevention and intervention, but findings have either been lacking or controversial. Thus the aim of this study is to provide a detailed picture of gender, weight, and age-related variations in the perception of appearance-related social pressure by peers and parents.
Methods
1112 German students between grades 7 and 9 (mean age: M = 13.38, SD = .81) filled in the Appearance-Related Social Pressure Questionnaire (German: FASD), which considers different sources (peers, parents) as well as various kinds of social pressure (e.g. teasing, modeling, encouragement).
Results
Girls were more affected by peer pressure, while gender differences in parental pressure seemed negligible. Main effects of grade-level suggested a particular increase in indirect peer pressure (e.g. appearance-related school and class norms) from early to middle adolescence. Boys and girls with higher BMI were particularly affected by peer teasing and exclusion as well as by parental encouragement to control weight and shape.
Conclusion
The results suggest that preventive efforts targeting body concerns and disordered eating should bring up the topic of appearance pressure in a school-based context and should strengthen those adolescents who are particularly at risk - in our study, girls and adolescents with higher weight status. Early adolescence and school transition appear to be crucial periods for these efforts. Moreover, the comprehensive assessment of appearance-related social pressure appears to be a fruitful way to further explore social risk-factors in the development of a negative body image.
Background: The use of psychoactive substances to neuroenhance cognitive performance is prevalent. Neuroenhancement (NE) in everyday life and doping in sport might rest on similar attitudinal representations, and both behaviors can be theoretically modeled by comparable means-to-end relations (substance-performance). A behavioral (not substance-based) definition of NE is proposed, with assumed functionality as its core component. It is empirically tested whether different NE variants (lifestyle drug, prescription drug, and illicit substance) can be regressed to school stressors.
Findings: Participants were 519 students (25.8 +/- 8.4 years old, 73.1% female). Logistic regressions indicate that a modified doping attitude scale can predict all three NE variants. Multiple NE substance abuse was frequent. Overwhelming demands in school were associated with lifestyle and prescription drug NE.
Conclusions: Researchers should be sensitive for probable structural similarities between enhancement in everyday life and sport and systematically explore where findings from one domain can be adapted for the other. Policy makers should be aware that students might misperceive NE as an acceptable means of coping with stress in school, and help to form societal sensitivity for the topic of NE among our younger ones in general.
Background
Natural accessions of Arabidopsis thaliana are a well-known system to measure levels of intraspecific genetic variation. Leaf starch content correlates negatively with biomass. Starch is synthesized by the coordinated action of many (iso)enzymes. Quantitatively dominant is the repetitive transfer of glucosyl residues to the non-reducing ends of α-glucans as mediated by starch synthases. In the genome of A. thaliana, there are five classes of starch synthases, designated as soluble starch synthases (SSI, SSII, SSIII, and SSIV) and granule-bound synthase (GBSS). Each class is represented by a single gene. The five genes are homologous in functional domains due to their common origin, but have evolved individual features as well. Here, we analyze the extent of genetic variation in these fundamental protein classes as well as possible functional implications on transcript and protein levels.
Findings
Intraspecific sequence variation of the five starch synthases was determined by sequencing the entire loci including promoter regions from 30 worldwide distributed accessions of A. thaliana. In all genes, a considerable number of nucleotide polymorphisms was observed, both in non-coding and coding regions, and several amino acid substitutions were identified in functional domains. Furthermore, promoters possess numerous polymorphisms in potentially regulatory cis-acting regions. By realtime experiments performed with selected accessions, we demonstrate that DNA sequence divergence correlates with significant differences in transcript levels.
Conclusions
Except for AtSSII, all starch synthase classes clustered into two or three groups of haplotypes, respectively. Significant difference in transcript levels among haplotype clusters in AtSSIV provides evidence for cis-regulation. By contrast, no such correlation was found for AtSSI, AtSSII, AtSSIII, and AtGBSS, suggesting trans-regulation. The expression data presented here point to a regulation by common trans-regulatory transcription factors which ensures a coordinated action of the products of these four genes during starch granule biosynthesis. The apparent cis-regulation of AtSSIV might be related to its role in the initiation of de novo biosynthesis of granules.
Introduction: We examined patterns of genetic divergence in 26 Mediterranean populations of the semi-terrestrial beachflea Orchestia montagui using mitochondrial (cytochrome oxidase subunit I), microsatellite (eight loci) and allozymic data. The species typically forms large populations within heaps of dead seagrass leaves stranded on beaches at the waterfront. We adopted a hierarchical geographic sampling to unravel population structure in a species living at the sea-land transition and, hence, likely subjected to dramatically contrasting forces.
Results: Mitochondrial DNA showed historical phylogeographic breaks among Adriatic, Ionian and the remaining basins (Tyrrhenian, Western and Eastern Mediterranean Sea) likely caused by the geological and climatic changes of the Pleistocene. Microsatellites (and to a lesser extent allozymes) detected a further subdivision between and within the Western Mediterranean and the Tyrrhenian Sea due to present-day processes. A pattern of isolation by distance was not detected in any of the analyzed data set.
Conclusions: We conclude that the population structure of O. montagui is the result of the interplay of two contrasting forces that act on the species population genetic structure. On one hand, the species semi-terrestrial life style would tend to determine the onset of local differences. On the other hand, these differences are partially counter-balanced by passive movements of migrants via rafting on heaps of dead seagrass leaves across sites by sea surface currents. Approximate Bayesian Computations support dispersal at sea as prevalent over terrestrial regionalism.
Biological age
(2013)
Leuchtkäfer & Orgelkoralle
(2013)
Leuchtende Käfer und Medusen, phosphoreszierende Meereswellen oder zu Stein erstarrende Korallen faszinierten den bisher vornehmlich als Dichter portraitierten Naturforscher Adelbert von Chamisso (1781–1838). Intensiver noch als den zoologischen und geologischen Phänomenen, widmete er sich der Scientia amabilis – der liebenswerten Wissenschaft von den Pflanzen. Der vielseitig Talentierte verfasste seine Reise um die Welt (1836), die bis heute als eine der stilistisch anspruchvollsten und lesenswertesten Reisebeschreibungen gilt. Diese Studie widmet sich dezidiert den naturkundlichen Studien Chamissos im Kontext der dreijährigen Rurik-Expedition sowie den zugehörigen Textproduktionen. Mit einem umfassenden Text- und Materialkorpus werden literatur- und kulturwissenschaftliche sowie wissenschaftshistorische Fragestellungen an das Werk gelegt und ertragreich beantwortet. Für die Reiseliteraturforschung wird bisher unbeachtetes Quellenmaterial ans Licht gebracht, gängige Thesen werden widerlegt, Quellen anderer Besatzungsmitglieder vergleichend betrachtet. Die Studie stellt den Naturforscher Chamisso in den Fokus, ohne den Dichter auszublenden, und widmet sich Fragen der Generierung, Vernetzung und Darstellung naturkundlichen Wissens in Texten, Illustrationen und Materialien zur Expedition – sie ist insgesamt für die Literatur- und Geschichtswissenschaft ebenso innovativ wie für die interdisziplinäre Geschichte des Wissens.
Dieser Band beschäftigt sich mit den theoretischen Grundlagen und der praktischen Umsetzung von Krafttraining mit Kindern und Jugendlichen. Ausgehend von der Kennzeichnung der körperlichen Situation und der Kraftentwicklung im Kindes- und Jugendalter werden die Effekte von Krafttraining bei Kindern und Jugendlichen aufgezeigt. Hierzu zählen neben Verbesserungen der Kraftausdauer, der Maximal- und Schnellkraft, die Förderung elementarer und sportartspezifischer Fertigkeiten sowie die günstige Beeinflussung gesundheitsrelevanter Faktoren (u.a. Verletzungshäufigkeit, Knochenstatus, kardio-vaskuläre und psycho-soziale Kennwerte).
Im Anschluss werden neuronale und muskuläre Mechanismen zur Erklärung der trainingsbedingten Anpassungen beschrieben. Das Kernstück des Buches bildet die Darstellung und Beschreibung vielfältiger Übungsbeispiele für ein Krafttraining an Maschinen, mit Freihanteln, Zusatzgeräten, dem eigenen Körpergewicht und ein Sprungkrafttraining. Hierbei wurden insbesondere Übungen ausgewählt, die sich für den Einsatz im Schul- und Vereinssport eignen. Dieses Buch dient somit Lehrern, Übungsleitern und Trainern, ein zielgerichtetes Krafttraining mit Kindern und Jugendlichen wirkungsvoll und sicher durchzuführen.
Global commons form a comparatively new part of international law, since the term appeared in international discussions and codifications only in the second half of the 20th century. The Common Heritage of Mankind is the corresponding legal principle that can establish an international regime to determine the legal status of non-sovereign territories and to allocate exploitation rights. Its main aim is to balance competing national claims by emphasising mankind’s common interest in the preservation and controlled exploitation of natural re-
sources. Against this background, the chapter sheds a critical light on attempts to transfer the institute of the Common Heritage of Mankind to the sphere of communication. Taking debates revolving around the New World Information and Communication Order in the framework of UNESCO since the late 1970s as a starting point, the author analyses the pitfalls and limits of attempts to establish governance structures for a global information order, including recent attempts to govern the internet.
Die Arbeit befasst sich mit der Schilderung von Paris im Erzählwerk von Delphine de Vigan, unter besonderer Berücksichtigung von zwei Romanen, No et moi (2007) und Les heures souterraines (2009), in denen der Großstadthintergrund einen zentralen Stellenwert erhält. Die Fragestellung richtet sich auf die Aspekte der Stadtdarstellung und auf die Rolle, die unterirdischen Durchgangsräumen dabei zugesprochen wird. Mögliche autoreflexive Deutungen der Stadt-Inszenierung in Bezug auf Sprache und Text, sowie Spuren einer mythisch-realistischen Charakterisierung der Stadt als Projektionsoberfläche des Imaginären
werden zum Schluss betrachtet.
Consciousness for fair consumption : conceptualization, scale development and empirical validation
(2013)
Sustainable consumption means that consumers act in an environmentally and socially responsible manner. Compared with the vast amount of studies concerning environmentally conscious consumer behaviour, relatively little is known about socially conscious consumption. The present paper focuses on fair consumption as an important aspect of social consumption. In our study, consciousness for fair consumption (CFC) is defined as a latent disposition of consumers to prefer products that are produced and traded in compliance with fair labour and business practices. A scale to measure CFC was conceptualized and tested in three independent empirical studies. Two studies were conducted at European universities (2010 and 2012) and used 352 and 362 undergraduate business students respectively. The third study, conducted in 2011, used 141 employees at a European university. The results confirmed the reliability and validity of the new CFC scale across samples. While being moderately related to other aspects of sustainable consumption such as ecological concern and moral reasoning, CFC was significantly distinct from those concepts. Most importantly, it was established that the CFC, as measured by the new CFC scale, is a strong determinant of consumption of fair trade products that has been neglected in existing research.
The “triple bottom line” concept (planet, people, and profit) represents an important guideline for the sustainable, hence future-oriented, development of societies and for the behaviors of all societal members. For institutions promoting societal change, as well as for companies being confronted with growing expectations regarding compelling contributions to sustainable changes, it is of great importance to know if, and to what extent, consumers have already internalized the idea of sustainability. Against the background of existing research gaps regarding a comprehensive measurement of the consciousness for sustainable consumption (CSC), the authors present the result of a scale development. Consciousness was operationalized by weighting personal beliefs with the importance attached by consumers to sustainability dimensions. Four separate tests of the CSC scale indicated an appropriate psychometric quality of the scale and provided support for this new measurement approach that incorporates the environmental, social and economic dimensions of sustainability.
Der Staat im Recht – getragen vom und gebunden durch das Recht, orientiert an Gemeinwohl und Individualrechten gleichermaßen – ist Gegenstand und Ziel des wissenschaftlichen Wirkens von Eckart Klein.
Eckart Klein, dessen 70. Geburtstag Anlass zu dieser Festschrift ist, hat sich als Rechtswissenschaftler dem Öffentlichen Recht in seiner ganzen Bandbreite gewidmet, wobei die Tätigkeit am Heidelberger Max-Planck-Institut für ausländisches öffentliches Recht und Völkerrecht und die Zeit als wissenschaftlicher Mitarbeiter am Bundesverfassungsgericht seine Interessen nachhaltig geprägt und fokussiert haben. Wichtige Themen seiner Publikationstätigkeit während seiner gesamten wissenschaftlichen Laufbahn sind dementsprechend das Verfassungsprozessrecht, das allgemeine Völkerrecht, das Recht der internationalen Organisationen und der internationale Menschenrechtsschutz.
Nach einer Station an der Johannes Gutenberg-Universität in Mainz wechselte er an die Universität Potsdam. Hier gründete er auch das MenschenRechtsZentrum der Universität Potsdam, dem er als Direktor vorstand. Der Jurist ergänzte seine Tätigkeit als Hochschullehrer durch die Wahrnehmung von Richterämtern an den Oberverwaltungsgerichten in Koblenz und Frankfurt (Oder) sowie am Staatsgerichtshof in Bremen. Außerdem war er Mitglied des Menschenrechtsausschusses der Vereinten Nationen und wirkte mehrfach als deutscher Ad-hoc-Richter an Verfahren vor dem Europäischen Gerichtshof für Menschenrechte mit. Dass bei alldem die akademische Lehre nicht zu kurz kam, war für Eckart Klein oberstes Gebot.
Schüler und Weggefährten haben in dieser Festschrift Beiträge aus den Bereichen des Völkerrechts, des Europarechts und des nationalen Rechts versammelt, um die Position des Staates im Recht aus unterschiedlichen Blickwinkeln auszuloten, Grenzen staatlichen Handelns zu markieren und nach Maßstäben für hoheitliche Entscheidungen zu fragen.
Les représentants du relativisme linguistique du XXème siècle qui se réclament de l’histoire de leur théorie mentionnent normalement Guillaume de Humboldt comme initiateur de l’idée que la manière particulière de penser d’un peuple dépendrait de sa langue. La théorie de Humboldt s’avère, cependant, difficilement maniable dans la recherche linguistique. Malgré une similitude évidente dans certaines positions, comme par exemple les concepts d’‘articulation’ et de ‘valeur’, le renouvellement de la linguistique sur une base saussurienne, au début du XXème siècle, se passait des idées de Humboldt. Il n’y avait que quelques philologues ‘idéalistes’ qui poursuivaient ce type de recherche. Ainsi, Karl Vossler constatait un parallélisme entre la langue et la culture et les considérait comme résultats de la création humaine. Le mécontentement quant à la description des langues selon le paradigme positiviste des néogrammairiens s’articulait nettement.
Le concept d’une vision linguistique du monde fut développé dans la théorie des néohumboldtiens (Weisgerber, Trier et autres) qui affirmaient que l’individu s’approprie le monde à travers la langue. Des différences entre des langues influeraient considérablement sur les facultés cognitives des hommes et sur leur comportement. L’idée humboldtienne de l’energeia se trouvait exclue de ces théories qui aspiraient à un renouvellement de la langue maternelle dans le sens d’une ‘grammaire à partir du contenu’ (inhaltbezogene Grammatik). Ce type de réflexion linguistique se prêtait aussi à une utilisation politique sous le national-socialisme. La théorie de Weisgerber, déclarée comme antiraciste et anti-national-socialiste par l’auteur lui-même, fut considérée comme « mother-tongue fascism » par Christopher Hutton. La relation entre le relativisme linguistique et la doctrine nationale-socialiste est évidente dans les écrits de plusieurs auteurs, par exemple dans « notre langue maternelle comme arme et instrument de la pensée allemande » de Georg Schmidt-Rohr. Il y eut des implications racistes de la théorie de quelques indo-germanistes bien avant 1933.
L’influence des néohumboldtiens s’est poursuivie jusqu’aux années 60, époque où ils durent faire place à des linguistes structuralistes et générativistes. On trouve dans quelques vérifications plus récentes du relativisme linguistique des références à des textes antérieurs à Humboldt. Par exemple, Gumperz et Levison (1996) citent le concours de l’Académie de Berlin sur la question suivante : Quelle est l'influence réciproque des opinions du peuple sur le langage et du langage sur les opinions? Est-ce que cet élargissement de l’horizon de rétrospection a quelque chose à voir avec la conscience d’une portée sociale possible de cette théorie ?