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Chemical and population genetic analysis show no evidence of ecotype formation in a European population of the parasitoid wasp Nasonia vitripennis
No full textEcotypes, subpopulations or strains of a single species locally adapted to divergent ecological conditions within the same habitat are often considered to be the first steps in sympatric speciation. It has been suggested that two ecotypes are distinguishable in 'Nasonia vitripennis', a prominent model organism for parasitic Hymenoptera, with one ecotype parasitizing fly pupae in bird nests, and the other one parasitizing fly pupae on carrion. This differentiation into two ecotypes has been hypothesized to indicate incipient sympatric speciation in populations of this globally distributed species. In the present study, we investigated the differentiation into these two distinct ecotypes focusing on chemical profiles and the population genetic divergence in a wild 'N. vitripennis' population from the Netherlands. Isofemale lines were obtained from bird nest boxes and from deer carrion, respectively, representing both microhabitats. To test for phenotypic differentiation, we determined the surface cuticular hydrocarbon (CHC) profiles from wasps of both host patches. Using a panel of 14 microsatellites, we concordantly determined the population genetic structure and tested for genetic differentiation between foundresses obtained from both microhabitats. Both the phenotypic as well as the genetic datasets show no evidence for any kind of separation based on the postulated two ecotypes, but rather suggest free interbreeding with no gene flow interruption between the two distinct host patches. Our findings challenge previous assumptions on clearly distinguishable ecotypes in 'N. vitripennis', and demonstrate how a chemical ecological assessment coupled with population genetics can be instrumental in re-evaluating the potential of ecological differentiation and incipient speciation mechanisms in parasitoid wasps
Crystal structure of bis(diisopropylamino)fluoroborane
No full textThe predominantly planar structure of a fluoro-substituted bis(dialkylamino)borane, C12H28BFN2, was obtained from the reaction of boron trifluoride diethyl etherate with lithium diisopropylamide and its structure is presented here. While the B—F bond length is in the typical range of single B—F bonds, the B—N bond length indicates a partial double-bond character. The sterically demanding isopropyl groups on both amides increase the N—B—N angle and enable intermolecular van der Waals interactions
Die Soziale Plastik von Joseph Beuys als Grundlage einer konstruktiven Sozialisation. Die sozialen Aspekte des erweiterten Kunstbegriffes
No full textDie Arbeit untersucht die Soziale Plastik von Joseph Beuys unter dem Aspekt einer Logik des Sozialen und fragt nach einer spezifischen Sichtweise der Sozialisation bei Beuys. Im Fokus stehen hier auch die allgemeinen Aspekte, die jeder Sozialisation zugrunde liegen und inwiefern sie der Gemeinschaft dienlich sind. Hauptthemen: Vergangenheitsbewältigung, Aufarbeitung von Traumata wie auch die Hinwendung zu religiösen Thematiken, die ebenso die Sichtweise des Philosophischen, Ethischen mit jener Sichtweise der Kunst und der Kunstgeschichte vergleichen. Die Arbeiten der Soziologen Durkheim, Mead, Parsons, Bourdieu, Grundmann sind ebenso Eckpunkte wie auch die Werke der Philosophen Schleiermacher, Fichte, Wittgenstein, Nietzsche und Rudolf Steiner. Damit zeigt sich die Dissertation in ihrer Ausrichtung interdisziplinär.The work investigates social sculpture by Joseph Beuys under aspect of social logic and asks, whether a specific view of the social exists in the work of Beuys. The focus here is also on the general aspects which underlie every socialization and asks in what way they serve the community. The main themes are: Coming to terms with the past, the working through trauma, as well as the turn to religious themes, which also compare the view of the philosophical, the view of the ethical with that view of art and art history. In this dissertation the works of the sociologists Durkheim, Mead, Parsons, Bourdieu, Grundmann are just as important as the works of the philosophers Schleiermacher, Fichte, Wittgenstein, Nietzsche and Rudolf Steiner. This shows that the dissertation is an interdisciplinary work
Digitalisierungen in Schule und Bildung als gesamtgesellschaftliche Herausforderung:Perspektiven zwischen Wissenschaft, Praxis und Recht
No full textDigitalisierung ist ohne Zweifel eines der bestimmenden Zukunftsthemen der frühen 2020er-Jahre und als solches sowohl gesamtgesellschaftlich als auch für die am Bildungswesen beteiligten Akteur*innen von hoher praktischer Relevanz. Der Sammelband verbindet Beiträge aus Erziehungswissenschaft und Bildungsforschung, Schulpraxis, Recht und Bildungspolitik. Ziel ist es, eine Orientierung zu Fragen der Digitalisierung(en) sowie deren Implikationen im schulischen Kontext anhand der schulgestalterischen Bereiche Organisationsentwicklung, Unterrichtsentwicklung und Personalentwicklung zu geben. Dabei zeigen wissenschaftliche Beiträge aktuelle Diskurs- und Forschungslinien auf; Fokusbeiträge werfen kaleidoskopartige Schlaglichter auf virulente Themenfelder jenseits des Diskurses (wie z. B. ethische Fragen im Umgang mit Algorithmen)
Donor Proteinuria and Allograft Function in Kidney Transplantation: Short- and Long-Term Results From a Retrospective Cohort Study
No full textDonor proteinuria (DP) is a common but rarely evaluated aspect of today’s kidney transplant allocation process. While proteinuria after kidney transplantation is a risk factor for impaired graft function and survival, the long-term effects of DP in kidney transplantation have not yet been evaluated. Therefore, this study aims to investigate the impact of DP on the long-term outcome after kidney transplantation. A total of 587 patients were found to be eligible and were stratified into two groups: (1) those receiving a graft from a donor without proteinuria (DP−) and (2) those receiving a graft from a donor with proteinuria (DP+). At 36 months, there was no difference in the primary composite endpoint including graft loss and patient survival (log-rank test, p = 0.377). However, the analysis of DP+ subgroups showed a significant decrease in overall patient survival in the group with high DP (p = 0.017). DP did not adversely affect patient or graft survival over 36 months. Nevertheless, this work revealed a trend towards decreased overall survival of patients with severe proteinuria in the subgroup analysis. Therefore, the underlying results suggest caution in allocating kidneys from donors with high levels of proteinuria
Educational robotics in higher education for promoting pre-service primary school teachers:A study on expanding computational thinking
No full textDieses Kapitel präsentiert die Ergebnisse einer quantitativen Längsschnittstudie, die die Selbsteinschätzung der professionellen digitalen Kompetenz angehender Grundschullehrkräfte untersucht. Die Studie befasst sich mit der Frage, wie ein Interventionsseminar diese Einschätzungen beeinflusst. Der Schwerpunkt liegt auf der Förderung der Kompetenz angehender Grundschullehrkräfte im Bereich des Computational Thinking und ihrer Kompetenz, Schüler:innen dieses zu vermitteln. Denn angehende Grundschullehrkräfte stehen bereits vor der Herausforderung, Schüler:innen digitale Kompetenzen zu vermitteln, sie auf zukünftige Entwicklungen in der Digitalisierung vorzubereiten und sie für die Auswirkungen auf Lernprozesse, Unterrichtsmethoden und den Alltag zu sensibilisieren. Im universitären Seminar werden Lehr-Lern-Szenarien mit Bildungsrobotern eingesetzt, durch die angehende Grundschullehrkräfte ihre Kompetenz im Computational Thinking erweitern und ihre Vermittlungsfähigkeiten trainieren. (Übers.)This chapter presents the results of a quantitative longitudinal study that examines the assessment of the professional digital competence of pre-service primary school teachers. The study explores the question of how an intervention seminar influences these assessments. The focus is on promoting pre-service primary school teachers’ competence in computational thinking and their competence in teaching computational thinking to pupils. This is because pre-service primary school teachers are already challenged to teach pupils digital skills, prepare them for future developments in digitalization, and sensitize them to the effects on learning processes, teaching methods, and everyday life. Educational robotics teaching-learning settings are used in university teaching, by which pre-service primary school teachers expand their competence in computational thinking and train their mediation skills
Higher spin representations of maximal compact subalgebras of simply laced Kac–Moody algebras
No full textGiven the maximal compact subalgebra k(A) of a split-real Kac–Moody algebra g(A) of type A, we study certain finite-dimensional representations of k(A) that do not lift to the maximal compact subgroup K(A) of the minimal Kac–Moody group G(A) associated to g(A) but only to its spin cover Spin(A) described in [11]. Currently, four elementary of these so-called spin representations are known. We study their (ir)reducibility, semisimplicity, and lift to the group level. The interaction of these representations with the spin-extended Weyl group is used to derive a partial parametrization result of the representation matrices by the real roots of g(A)