University of Konstanz
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Who is willing to play skill-adapted exergames? : Influences of sociodemographic factors and social comparison processes
No full textPhysical inactivity bears risks for physical and mental health. Theoretically grounded, novel intervention approaches are needed that encourage a positive affective reaction. Exergames may provide this opportunity, especially if different skill levels of players are automatically adapted. Drawing from two pre-registered within-subjects online experiments (total N = 1931) where participants were presented with two scenarios (joining exergame as most versus least skilled player), we report on the willingness of adults to engage in (skill-adapted) exergames. We also describe individual differences in willingness based on sociodemographic characteristics and social comparison processes. Willingness was higher when joining as the most versus the least skilled player among younger (rs = −0.28) and more highly educated (rs 0.07 and 0.12) participants, and among those who owned gaming consoles (vs. not; ds 0.28 and 0.45) and had prior exergame experience (vs. not; ds −0.42 and −0.51). Men were more willing to join exergames as the least skilled player than women (d = −0.16). Social comparison orientation was positively associated with willingness (rs 0.08 to 0.22), as were tendencies to engage in upward identification (rs 0.18 and 0.21) and downward contrast (rs 0.12 and 0.17). Tailoring exergames to sociodemographic and psychological characteristics is likely to maximise their effectiveness for health promotion.publishe
Genomic signatures of adaptation to stress reveal shared evolutionary trends between Tetrahymena utriculariae and its algal endosymbiont, Micractinium tetrahymenae
No full textThe evolution of intracellular endosymbiosis marks a major transition in the biology of the host and endosymbiont. Yet, how adaptation manifests in the genomes of the participants remains relatively understudied. We investigated this question by sequencing the genomes of Tetrahymena utriculariae, a commensal of the aquatic carnivorous bladderwort Utricularia reflexa, and its intracellular algae, Micractinium tetrahymenae. We discovered an expansion in copy number and negative selection in a TLD domain-bearing gene family in the genome of T. utriculariae, identifying it as a candidate for being an adaptive response to oxidative stress resulting from the physiology of its endosymbionts. We found that the M. tetrahymenae genome is larger than those of other Micractinium and Chlorella and contains a greater number of rapidly expanding orthogroups. These were enriched for Gene Ontology terms relevant to the regulation of intracellular signal transduction and cellular responses to stress and stimulus. Single-exon tandem repeats were overrepresented in paralogs belonging to these rapidly expanding orthogroups, which implicates long terminal repeat retrotransposons (LTRs) as potential agents of adaptation. We additionally performed a comparative transcriptomic analysis of M. tetrahymenae in a free-living state and in endosymbiosis with T. utriculariae and discovered that the genes that are differentially expressed were enriched for pathways that evidence shifts in energy generation and storage and in cellular protection strategies. Together, our results elucidate the axes along which the participants must adapt in this young endosymbiosis and highlight evolutionary responses to stress as a shared trend.publishe
MIBiG 4.0 : advancing biosynthetic gene cluster curation through global collaboration
No full textSpecialized or secondary metabolites are small molecules of biological origin, often showing potent biological activities with applications in agriculture, engineering and medicine. Usually, the biosynthesis of these natural products is governed by sets of co-regulated and physically clustered genes known as biosynthetic gene clusters (BGCs). To share information about BGCs in a standardized and machine-readable way, the Minimum Information about a Biosynthetic Gene cluster (MIBiG) data standard and repository was initiated in 2015. Since its conception, MIBiG has been regularly updated to expand data coverage and remain up to date with innovations in natural product research. Here, we describe MIBiG version 4.0, an extensive update to the data repository and the underlying data standard. In a massive community annotation effort, 267 contributors performed 8304 edits, creating 557 new entries and modifying 590 existing entries, resulting in a new total of 3059 curated entries in MIBiG. Particular attention was paid to ensuring high data quality, with automated data validation using a newly developed custom submission portal prototype, paired with a novel peer-reviewing model. MIBiG 4.0 also takes steps towards a rolling release model and a broader involvement of the scientific community. MIBiG 4.0 is accessible online at https://mibig.secondarymetabolites.org/.publishe
Indexical utility : another rationalization of exponential discounting
No full textThis paper is about time preferences, the phenomenon that the very same things are usually considered the less valuable the farther in the future they are obtained. The utilities of those things are discounted at a certain rate. The paper presents a novel normative argument for exponential discount rates, whatever their empirical adequacy. It proposes to take indexical utility seriously, i.e. utilities referring to indexical propositions (that speak of ‘I’, ‘now’, etc.) as opposed to non-indexical propositions. Economic focus is only on the latter, while the former are neglected. The potential ignorance of when is now generates a difference between indexical and non-indexical utility that can be exploited for a novel argument in favour of exponential discount rates.publishe
Deciphering the significance of p53 mutant proteins
No full textMutations in the p53 gene compromise its role as guardian of genomic integrity, yielding predominantly missense p53 mutant proteins. The gain-of-function hypothesis has long suggested that these mutant proteins acquire new oncogenic properties; however, recent studies challenge this notion, indicating that targeting these mutants may not impact the fitness of cancer cells. Mounting evidence indicates that tumorigenesis involves a cooperative interplay between driver mutations and cellular state, influenced by developmental stage, external insults, and tissue damage. Consistently, the behavior and properties of p53 mutants are altered by the context. This article aims to provide a balanced summary of the evolving evidence regarding the contribution of p53 mutants in the biology of cancer while contemplating alternative frameworks to decipher the complexity of p53 mutants within their physiological contexts.publishe
Künstliche Intelligenz (KI) im Studienalltag : Einschätzungen von Studierenden zum Einsatz von KI an deutschen Hochschulen
No full textMit dem Aufkommen leicht verfügbarer KI-Tools wie ChatGPT im Jahr 2023 hat auch unter Studierenden deutscher Universitäten die Nutzung von künstlicher Intelligenz im Studienalltag stark zugenommen. In dem vorliegenden Bericht werden Ergebnisse einer Rapid-Response-Studie vorgestellt, bei der zu Beginn des Wintersemesters 2024/2025 bundesweit Studierende aller Fächergruppen und Hochschularten zu ihrem Nutzungsverhalen und zu ihren Einschätzungen zum Gebrauch von KI im Studienalltag vorgestellt. Untersucht werden dabei nicht nur die Häufigkeit der KI-Nutzung durch Studierende, die Anwendungsgebiete und die wahrgenommenen Vor- und Nachteile, sondern auch, wie die Hochschulen die KI-Nutzung aus Sicht der Studierenden unterstützen und regulieren.publishe
Tetratic phase in 2D crystals of squares
No full textMelting in two-dimensional (2D) systems is described by the celebrated Kosterlitz–Thouless–Halperin–Nelson–Young (KTHNY) theory, which explains how the unbinding of two types of topological defects destroys translational and orientational order at distinct temperatures. The intermediate hexatic phase, a fluid with six-fold quasi-long-ranged orientational order, has been observed in 2D colloidal monolayers of isotropic particles. In this study, we investigate the melting of a quadratic crystal with four-fold symmetry, composed of square particles of approximately 4 × 4 μm in size. These anisotropic particles were fabricated from photoresist using 3D nanoprinting. In an aqueous solution, the particles sediment onto a cover slide, forming a monolayer. The adjustable curvature of the cover slide precisely controls the monolayer density. At low densities, the particles exhibit free diffusion, forming a 2D fluid, while at high densities, they assemble into a quadratic crystal. Using a four-fold bond-order correlation function, we identify the tetratic phase with quasi-long ranged orientational order in close analogy to the hexatic phase in systems with six-fold symmetry.publishe
The interplay of trophic interactions and game dynamics gives rise to life-history trade-offs, consistent personalities, and predator–prey and aggression power laws
No full textEcological processes and evolutionary change are increasingly recognized as intimately linked. Here, we introduce an eco-evolutionary model of trophic interactions between predators and prey and show that the flow of resources in the ecosystem results in the scale-invariant spatial and temporal structure of ecosystems. In contrast to conventional approaches that rely on fitness-based selection, evolution in our eco-evolutionary framework is a direct consequence of ecological interactions. To illustrate this, we combine trophic interactions with evolutionary games by allowing individuals to play a game within the population where they can adopt aggressive or non-aggressive strategies. We show that individuals develop consistent personalities and their life-history trade-offs become intertwined with the scale-invariant ecological dynamics. Aggressive individuals tend to live faster, more reproduction-focused lives, whereas nonaggressive individuals favor slower, longer-lived strategies. These patterns emerge naturally, rather than being imposed as model assumptions. Furthermore, we demonstrate that the nonequilibrium dynamics of resource flow play a decisive role in driving the evolution of consistent personalities within and across populations. We identify a new class of aggression scaling laws arising from the interplay of ecological and evolutionary processes. The model relates predator–prey scaling laws with food web control and shows that small offspring size, high relative prey mobility, low predator conversion efficiency, predator competition, and prey competition all favor prey control over the food web. Our findings illuminate how large-scale ecological patterns—including power laws in predator–prey biomass and avalanche-like resource pulses—can relate to evolutionary outcomes such as consistent personalities, life-history trade-offs, and density-dependent growth. This perspective strengthens the emerging view that ecology and evolution are two faces of the same coin, each shaping the other in a self-organized, energy-driven system.publishe
The behavioral mechanisms governing collective motion in swarming locusts
No full textCollective motion, which is ubiquitous in nature, has traditionally been explained by “self-propelled particle” models from theoretical physics. Here we show, through field, lab, and virtual reality experimentation, that classical models of collective behavior cannot account for how collective motion emerges in marching desert locusts, whose swarms affect the livelihood of millions. In contrast to assumptions made by these models, locusts do not explicitly align with neighbors. While individuals respond to moving-dot stimuli through the optomotor response, this innate behavior does not mediate social response to neighbors. Instead, locust marching behavior, across scales, can be explained by a minimal cognitive framework, which incorporates individuals’ neural representation of bearings to neighbors and internal consensus dynamics for making directional choices. Our findings challenge long-held beliefs about how order can emerge from disorder in animal collectives.publishe