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Statistical analysis of EBSD data confirms pronounced classical and non-classical pervasive crystallographic twinning in rotaliid foraminiferal calcite
No full textWe describe a quantitative statistical and geometric analysis of classical and non-classical modes of twinning in the calcite produced by biomineralization in the shell of the rotaliid foraminifer species Amphistegina lessonii. Foraminifera are responsible for about a quarter of the marine production of CaCO3 and thus play a major role in the natural CO2 sequestration into marine carbonate sediments. The shell calcite of rotaliid foraminifera is nano-twinned and thus quite distinct from inorganic calcite and from biogenic calcite produced by other groups of organisms. Previous work showed that foraminiferal calcite contains a high spatial density of twin walls of the classical 60°| = m.{001} twin, but there was another peak in the range between 75° and 80° in the misorientation statistics of electron backscatter diffraction (EBSD) maps of the same specimen. We checked the significance of all maxima in misorientation by in-depth statistical analysis, thus confirmed the 60°| penetration twinning and found that the 75°–80° maxima are related to new, non-classical, but systematically reoccurring oriented associations of calcite crystals with orientation relationships 78.2°| and 76.6°|. If the nano-twinning provides an evolutionary advantage, it may increase the strength and toughness of the feeble mineralized chamber walls of the organisms.publishe
Flexible working time arrangements and work-life conflict : The role of gender and housework
No full textObjective: This paper studies how the relationship between flexible working time arrangements and self-reported work-to-life and life-to-work conflict is moderated by an (un)equal domestic labor distribution within heterosexual couples.
Background: Flexible working arrangements can give employees more autonomy in balancing paid employment with private life. However, studies have shown that this flexibility is used in gender-specific ways: while women devote more time to household chores, men increase their paid working hours. This article builds on these findings by exploring how the heterogeneity in the division of domestic labor within couples moderates the relationship between flexible working time arrangements and work–life conflict.
Method: Analyses are based on the German Family Panel (pairfam), Wave 12 (2019-2020) and include 2,032 partnered working individuals (1,162 women and 870 men). We applied linear regression models.
Results: Company-defined and autonomous work schedules were associated with a greater work-to-life conflict, especially for men, while women with complete control over their schedule experienced less conflict. The level of life-to-work conflict was similar across different schedules, except for women with flexitime, who reported higher conflict. Housework responsibilities also played a role, as women handling most household tasks faced greater life-to-work conflict with flexible schedules, and men with company-defined schedules experienced higher conflict in both directions when they shared housework equally with their partner.
Conclusion: Access to flexible working time arrangements alone may not reduce work-to-life and life-to-work conflict, as the impact depends on both gender and how housework is divided within a couple.publishe
Testing Strategies for Metabolite-Mediated Neurotoxicity
No full textCompounds, which rely on metabolism to exhibit toxicity, pose a challenge for next-generation risk assessment (NGRA). Since many of the currently available non-animal new approach methods (NAMs) lack metabolic activity, their use may lead to an underestimation of the true hazard to humans (false negative predictions). We explored here strategies to deal with metabolite-mediated toxicity in assays for developmental neurotoxicity. First, we present an overview of substances that may serve as potential positive controls for metabolite-related neurotoxicity. Then, we demonstrate, using the MitoMet (UKN4b) assay, which assesses the adverse effects of chemicals on neurites of human neurons, that some metabolites have a higher toxic potency than their parent compound. Next, we designed a strategy to integrate elements of xenobiotic metabolism into assays used for (developmental) neurotoxicity testing. In the first step of this approach, hepatic post-mitochondrial fractions (S9) were used to generate metabolite mixtures (“metabolisation module”). In the second step, these were applied to a NAM (exemplified by the UKN4b assay) to identify metabolite-mediated toxicity. We demonstrate the applicability and transferability of these approaches to other assays, by an exemplary study on the basis of the cMINC (UKN2) assay, another NAM of the developmental neurotoxicity in vitro battery. Based on the experience gained from these experiments, we discuss key issues to be addressed if this approach is to be used more broadly for NAM in the NGRA context.publishe
Behavioral sequences across multiple animal species in the wild share common structural features
No full textAnimal behavior can be decomposed into a sequence of discrete activity bouts over time. Analyzing the statistical structure of such behavioral sequences can provide insights into the drivers of behavioral decisions. Laboratory studies, predominantly in invertebrates, have suggested that behavioral sequences exhibit multiple timescales and long-range memory, but whether these results can be generalized to other taxa and to animals in natural settings remains unclear. By analyzing accelerometer-inferred predictions of behavioral states in three species of social mammals (meerkats, white-nosed coatis, and spotted hyenas) in the wild, we found surprisingly consistent structuring of behavioral sequences across all behavioral states, all individuals, and all study species. Behavioral bouts were characterized by decreasing hazard functions, wherein the longer a behavioral bout had progressed, the less likely it was to end within the next instant. The predictability of an animal’s future behavioral state as a function of its present state always decreased as a truncated power-law for predictions made farther into the future, with very similar estimates for the power law exponent across all species. Finally, the distributions of bout durations were also heavy-tailed. Why such shared structural principles emerge remains unknown, and we explore multiple plausible explanations, including environmental nonstationarity, behavioral self-reinforcement, and the hierarchical nature of behavior. The existence of highly consistent patterns in behavioral sequences across our study species suggests that these phenomena could be widespread in nature, and points to the existence of fundamental properties of behavioral dynamics that could drive such convergent patterns.publishe
Penguins exploit tidal currents for efficient navigation and opportunistic foraging
No full textAnimals navigating in fluid environments often face forces from wind or water currents that challenge travel efficiency and route accuracy. We investigated how 27 Magellanic penguins (Spheniscus magellanicus) adapt their navigation strategies to return to their colony amid regional tidal ocean currents. Using GPS-enhanced dead-reckoning loggers and high-resolution ocean current data, we reconstructed penguin travel vectors during foraging trips to assess their responses to variable currents during their colony-bound movements. By integrating estimates of energy costs and prey pursuits, we found that birds balanced direct navigation with current-driven drift: in calm currents, they maintained precise line-of-sight headings to their colony. In stronger currents, they aligned their return with lateral flows, which increased travel distance, but at reduced energy costs, and provided them with increased foraging opportunities. Since the lateral tidal currents always reversed direction over the course of return paths, the penguins’ return paths were consistently S-shaped but still resulted in the birds returning efficiently to their colonies. These findings suggest that Magellanic penguins can sense current drift and use it to enhance energy efficiency by maintaining overall directional accuracy while capitalizing on foraging opportunities.publishe
Parametric instability landscape of coupled Kerr parametric oscillators
No full textNetworks of coupled Kerr parametric oscillators (KPOs) hold promise for the realization of neuromorphic and quantum computation. Yet, their rich bifurcation structure remains poorly understood. Here, we employ secular perturbation theory to map the stability regions of these networks and identify the regime where the system can be mapped to an Ising model. Starting with two coupled KPOs, we show how the bifurcations arise from the competition between the global parametric drive and linear coupling between the KPOs. We then extend this framework to larger networks with all-to-all equal coupling, deriving analytical expressions for the full cascade of bifurcation transitions. In the thermodynamic limit, we find that these transitions become uniformly spaced, leading to a highly regular structure. Our results reveal the precise bounds under which KPO networks have an Ising-like solution space, and thus provide crucial guidance for their experimental implementation.publishe
Competing Principals in a Multinational State : Legislative Behavior in Imperial Austria, 1907–1914
No full textThis article examines legislative behavior in the lower house of the Imperial Austrian Reichsrat, a historical legislature representing a multinational society. The coincidence of economic and center‐periphery cleavages in that democratizing state presents an excellent opportunity to examine the influence of multiple competing principals on representatives' legislative behavior. Drawing on an original dataset, we test under which conditions representatives voted against their parliamentary party group between 1907 and 1914. We find relatively high levels of unity, especially for the transnational Social Democrats. Where deviations occur, they are associated with the ethno‐national and economic composition of representatives' electoral districts and initially with membership in parliamentary professional associations. The findings highlight the importance of the center‐periphery (respectively transnational) cleavage as an additional driver of legislative behavior in parliaments, like the European Parliament or the parliaments of Spain or the United Kingdom, that represent multiple nations.publishe
Training effects of affordance judgments in four different settings : towards developing a training battery for affordance judgments
No full textTraining affordance judgments (AJs) across different settings, such as judging whether an object is within reach or an obstacle conquerable, could be meaningful to older adults and neurological patients with diminished judgment behaviors.
The long-term aim is to develop a comprehensive training battery with different types of AJ tasks. The present study used a between-subjects design to evaluate trainability in four different settings. Judgment behavior of 52 healthy young adults was trained (80 trials) in one out of four settings (per trained task N = 13): 1. Reaching horizontally forward for an object, 2. Fitting one hand horizontally into an aperture, 3. Fitting upright under a horizontal barrier, and 4. Stepping over a hurdle. Participants’ judgment performance was assessed pre- versus post-training. Additionally, to assess whether other AJ-based tasks as potential distractors may override training effects, the other three non-trained tasks were presented, and subsequently, judgment performance in the trained task was assessed once more. Accuracy, judgment tendency, and perceptual sensitivity served as dependent variables.
A Friedman Test revealed a main effect of time point in all three variables. Post hoc analyses showed significant improvements in the trained task even after exposure to other AJ tasks.
The results suggest that in young healthy adults, AJs can be trained effectively within different AJ settings, and improvements within one setting can last, even when AJs in other settings are solved in between. Our study provides proof of principle and an important step towards developing a training battery for AJs.publishe
Indikation von Uferstrukturbelastungen durch Makrophyten und Makrozoobenthos an Seen in Brandenburg : Teil 1: Datenbestand und Datenprüfung : Bericht der ARGE „Team Seeufer MMM“ für das Landesamt für Umwelt Brandenburg, Ref. W26, Projekt SuBoLakes (Az. 35825/01), AP 5 der Deutschen Bundesstiftung Umwelt (DBU)
No full textpublishe