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Immunoproteasome Inhibition Impairs Differentiation but Not Survival of T Helper 17 Cells
No full textAutoimmune and inflammatory diseases are characterized by aberrant immune responses. The immunoproteasome was proposed as a target for such Th cell-mediated diseases due to its role in the activation, differentiation and function of T cells. Even though many studies demonstrated reductions in Th17 cells upon immunoproteasome inhibition, it is still unclear if the differentiation or survival of these cells is affected. Therefore, this study used DSS-induced colitis and house dust mite airway inflammation mouse models to investigate the effect of immunoproteasome inhibition on Th17 cells and Tregs at different time points. Th17 cells were almost abolished when immunoproteasome inhibition was applied continuously in DSS-induced colitis. In contrast, immunoproteasome inhibition did not decrease levels of already differentiated Th17 cells and did not enhance Treg induction. Dendritic cells were barely affected by immunoproteasome inhibition. Moreover, immunoproteasome inhibition reduced T cell activation in vitro and in vivo, suggesting impaired activation as the underlying mechanism for reduced Th17 differentiation. In conclusion, immunoproteasome inhibition reduces Th17 differentiation by impairing the activation of naïve T cells, but it does not affect the survival of already-differentiated Th17 cells and Tregs.publishe
Maxitive functions with respect to general orders
No full textIn decision-making, maxitive functions are used for worst-case and best-case evaluations. Maxitivity gives rise to a rich structure that is well-studied in the context of the pointwise order. In this article, we investigate maxitivity with respect to general preorders and provide a representation theorem for such functions. The results are illustrated for different stochastic orders in the literature, including the usual stochastic order, the increasing convex/concave order, and the dispersive order.publishe
The Promise of Board Gender Diversity : State of the Art and Conclusions
No full textIn the field of organizational behaviour, the effects of board gender diversity on corporate performance have been discussed controversially. This chapter summarizes theoretical arguments and empirical evidence for both the business and the moral justice cases for gender diversity in corporate boards. In addition, boundary conditions are considered under which beneficial effects of board gender diversity are more likely to occur (i.e., gender parity, gender quotas, and CEO leadership style). Further, the relevance of international research on board gender diversity for the German-speaking countries is discussed.publishe
Synthesis and X-ray structure analysis of cytotoxic 2-picolylamino-type Hf<sup>IV</sup>-bis-chelated complexes
No full textpublishe
Emergence of a Resource Acquisition Trade-off at the Community Scale during Environmental Change
No full textBiomass-weighted mean traits of a community's constituent species are a useful tool to assess environmental filtering in community function in response to environmental change. We show that annually averaged phytoplankton community function, expressed by the community mean traits phosphate and light affinity, responded strongly and reversibly to long-term changes in nutrient supply over a 42-year period of eutrophication and re-oligotrophication of Lake Constance. Within the lake's species pool, phosphate and light affinities were weakly negatively correlated, suggesting a weak physiological trade-off. Yet, a strong trade-off between these traits emerged when species were weighted by their biomass, suggesting species sorting along the trade-off line across years of shifting nutrient status. Emergent trade-offs, that is, trade-offs that become apparent first when trait combinations are weighted by the contributions of the trait-bearing organisms to community biomass, may be a useful, novel concept in trait-based ecology of potentially similar importance as commonly considered physiological trade-offs.publishe
Variation Diminution and Intervals of Sign Regular Matrices
No full textA sign regular matrix is a matrix having the property that its non-zero minors of all orders have for each order an identical sign. Such matrices appear in a wide range of applications. In this paper, intervals of real matrices with respect to the usual entry-wise partial ordering are considered. Using variation diminution, it is shown that all matrices in such an interval are sign-regular with the same signature of their minors if a specified finite set of element matrices in the interval has this property.publishe
Relational hyperevent models for the coevolution of coauthoring and citation networks
No full textThe development of appropriate statistical models has lagged behind the ambitions of empirical studies analysing large scientific networks—systems of publications connected by citations and authorship. Extant research typically focuses on either paper citation networks or author collaboration networks. However, these networks involve both direct relationships, as well as broader dependencies between references linked by multiple citation paths. In this work, we extend recently developed relational hyperevent models to analyse networks characterized by complex dependencies across multiple network modes. We introduce new covariates to represent theoretically relevant and empirically plausible mixed-mode network configurations. This model specification allows testing hypotheses that recognize the polyadic nature of publication data, while accounting for multiple dependencies linking authors and references of current and prior papers. We implement the model using open-source software to analyse publicly available data on a large scientific network. Our findings reveal a tendency for subsets of papers to be cocited, indicating that the impact of these papers may be partly due to endogenous network processes. More broadly, the analysis shows that models accounting for both the hyperedge structure of publication events and the interconnections between authors and references significantly enhance our understanding of the mechanisms driving scientific production and impact.publishe
Full spectrum of novelties in time-dependent urn models
No full textSystems driven by innovation, a pivotal force in human society, present various intriguing statistical regularities, from the Heaps' law to logarithmic scaling or somewhat different patterns for the innovation rates. The urn model with triggering (UMT) has been instrumental in modeling these innovation dynamics. Yet a generalization is needed to capture the richer empirical phenomenology. Here we introduce a time-dependent urn model with triggering (TUMT), a generalization of the UMT that crucially integrates time-dependent parameters for reinforcement and triggering to offer a broader framework for modeling innovation in nonstationary systems. Through analytical computation and numerical simulations, we show that the TUMT reconciles various behaviors observed in a broad spectrum of systems from patenting activity to the analysis of gene mutations. We highlight how the TUMT features a “critical” region where both Heaps' and Zipf's laws coexist, for which we compute the exponents.publishe
Prepared for the Multilingual Classroom? : Pre-Service Teachers' Beliefs with Respect to Multilingualism
No full textTeachers’ beliefs on issues of multilingualism shape their classroom practices, which in turn affect their multilingual students’ learning opportunities and academic achievement. Examining these beliefs is therefore crucial for teacher educators who strive to equip pre- and in-service teachers with the appropriate mindset that is necessary in the context of an educational landscape characterized by linguistic diversity. In this study, we examine German pre-service teachers’ knowledge of and beliefs toward multilingualism and their perceived preparedness for a multilingual classroom. We use a questionnaire that includes an internationally recognized scale to measure beliefs toward multilingualism Additionally, we investigate how a semester-long lecture on German as a second language (GSL) and language-sensitive teaching influences pre-service teachers’ beliefs. The results indicate that while German pre-service teachers demonstrate knowledge and awareness of multilingualism, there remains potential for fostering a more open belief system—one that is essential for effectively engaging with diverse student groups and should be systematically addressed during university education. Pre-service teachers who participated in the semester-long lecture showed slightly more multilingual beliefs. These findings provide a basis for discussing curricular opportunities aimed at promoting multilingualism and supporting language learning in educational settings.publishe
Insights into the genetic basis of bilateral head asymmetry in a scale-eating cichlid fish
No full textAlmost all animals are bilaterally symmetrical, and only rarely is this universality broken and maintained as a stable polymorphism. One such case is Perissodus microlepis, a scale-eating cichlid fish endemic to Lake Tanganyika. This species is polymorphic with left- or right-headed morphs, each specialized for scraping scales from the opposite side of their prey. This polymorphism is stably maintained around a 50:50 ratio and is likely driven by negative frequency–dependent selection, a classic form of balancing selection. Using a genome-wide dataset, including a de novo haplotype-resolved reference genome, whole-genome sequences, and microcomputed tomography scans of 102 individuals, we identified 72 genetic loci linked to head asymmetry. Nearby genes are enriched for roles in symmetry establishment, facial morphology, and nervous system function, with evidence suggesting that balancing selection maintains this diversity. Our study expands our understanding of the genetic basis of head asymmetry and provides candidate genes for further research.publishe