University of Konstanz
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Exact Versus Conceptual Replication : Internet-based Research Investigating the Replicability of Cognitive Effects
No full textIn recent years, the need for replication efforts has grown. Replication science faces key challenges, including achieving generalizability across heterogeneous samples and environments while streamlining the theory-experiment cycle to facilitate research efforts. Systematic replication projects using Internet-based methodologies address these challenges by facilitating access to diverse samples, employing rigorous testing, reducing costs, and ensuring materials are readily available. Standards for Internet-based experimenting provides transparency and reproducibility. We present three remote experiments, including one exact replication (N: 410) and two conceptual replications (N: 270; N: 365), which test the mental accounting effect based on Kahneman and Tversky’s classic paradigm. The remote version of the exact replication maintained the same experimental design, instructions, and procedure as the original paradigm. In the two conceptual replications, we adapted the original price to the current value of money: Ticket price and the monetary loss were changed from 10$ to 40€. In the first conceptual replication, we varied the original experimental design: the mental account variable was manipulated within-subjects. In the second conceptual replication, we varied the price stimulus while retaining the mental account manipulation in a between-subjects design. The exact replication replicated the original findings with an effect of small size, while the two conceptual replications replicated the results with an effect of increased size that is more comparable to the original findings. The results highlight the importance of adapting experimental paradigms to the current times, and the advantages of conducting remote replication projects step-by-step.publishe
Captivity alters behaviour but not seasonal brain size change in semi-naturally housed shrews
No full textCaptivity, frequently used in animal research, can profoundly alter brain size, cognitive abilities and activity levels. Critically, persistent exposure to stressors in captive environments can lead to chronic stress and subsequently to a range of health issues. However, the direct implications of captivity on research outcomes have not been thoroughly investigated. We examined the effects of captivity on the common shrew, Sorex araneus, a species that exhibits a profound seasonal reversible change in brain and body size. We compared wild shrews during summer and winter to assess seasonal changes in brain size and behaviour and then contrasted these findings with shrews kept in captivity for six months. Using repeated in vivo magnitic resonance imaging, we determined that the extent of seasonal brain size change was not affected by the semi-natural captive conditions. However, captivity led to increased activity levels and reduced learning motivation in the shrews, indicative of chronic stress. These results suggest that even semi-natural conditions can significantly alter the outcome of studies and these effects need to be quantified before experimentation.publishe
Processed food intake assortativity in the personal networks of older adults
No full textExisting research indicates that dietary habits spread through social networks, yet the impact on populations in Eastern Europe, particularly in rural areas, is less understood. We examine the influence of personal networks on the consumption of high-salt processed foods among individuals in rural Romania, with a specific focus on older adults. Using a personal network analysis, we analyze data from 83 participants of varying ages and their social contacts through multi-level regression models. The inclusion of participants across a wider age range allows us to capture the broader dynamics of social networks, reflecting the intergenerational nature of rural communities. Our findings reveal assortativity in dietary habits, indicating that individuals cluster with others who share similar food consumption patterns. Our results underscore the need for public health interventions that account for the influence of social networks on dietary behavior, as addressing high salt intake and its associated health risks may require considering the broader social context beyond older adults. The study contributes to understanding the social determinants of dietary behaviors and highlights the role of personal networks in shaping food choices in vulnerable populations.publishe
One-Step Aerosol Synthesis of Thiocyanate Passivated Hybrid Perovskite Microcrystals : Impact of (Pseudo-)Halide Additives on Crystallization and Access to a Novel Binary Model
No full textHybrid Perovskite materials have gone through an astonishing development due to their unique optoelectronic behavior, leading to the creation of a wide range of synthetic strategies. As the materials’ surface is found to play a crucial role with respect to the properties, e.g. hydration, stability and carrier mobilities, considerable efforts have been made to optimize the surface through various approaches. Especially the passivation of the perovskite surface attracted a lot of attention in this field, often resulting in more complex, multi-step synthetic processes. In this study, a simple one-step aerosol-assisted synthetic approach is presented to obtain thiocyanate (SCN) passivated single-crystal MAPbBr3 microcrystals. To elucidate the role of the additive in the crystallization process, mixed (pseudo-)halide precursors are systematically investigated. The as processed, passivated microcrystals exhibit enhanced stability and charge carrier lifetimes. Additionally, a decrease in surface photovoltage, attributed to the presence of the SCN additive, is observed. Furthermore, the aerosol process is further developed resulting in a novel binary system containing MAPbBr3-SCN perovskite microcrystals and Au nanostructures. This system serves as a promising model for further investigations into potential interactions between plasmonic and semiconducting materials, with initial results indicating prolonged charge carrier lifetimes.publishe
Effects of competence-based sustainable entrepreneurship education on secondary school students' sustainable entrepreneurial intention
No full textSustainable entrepreneurship is crucial for promoting economic growth while addressing environmental and social challenges to advance sustainable development. Sustainable entrepreneurs are driven by their intention to solve these sustainability challenges through entrepreneurial means. In higher education, sustainable entrepreneurship education is recognized as a driver of sustainable entrepreneurial intention and related antecedents, such as the attitude toward sustainable entrepreneurship.
Based on the theory of planned behavior, this study aims to examine the impact of competence-based sustainable entrepreneurship education on secondary students’ sustainable entrepreneurial intention and its antecedents. Additionally, the effect of the commonly studied background factors ‘gender’ and ‘exposure to sustainable entrepreneurial role models’ is explored. A controlled pre-post research design was employed between April and May 2023 to assess changes in dependent variables. Data were collected via a questionnaire from 169 students participating in sustainable entrepreneurship interventions in Southern Germany.
The findings indicate that sustainable entrepreneurship education has a significant positive effect on secondary school students’ sustainable entrepreneurial intention, attitude, subjective norm, and perceived behavioral control. The effect of the intervention on sustainable entrepreneurial intention, attitude, and perceived behavioral control is consistent across participants’ genders. Sustainable entrepreneurial role models did not significantly influence the measured constructs.
These results support the implementation of sustainable entrepreneurship education already into secondary school curricula, demonstrating its potential to enhance students' sustainable entrepreneurial intention and related antecedents. This study contributes to the theoretical understanding of sustainable entrepreneurial intention formation and offers insights for educators and policymakers aiming to foster sustainable entrepreneurial intention among youth.publishe
Studying collective animal behaviour with drones and computer vision
No full text1. Drones are increasingly popular for collecting behaviour data of group‐living animals, offering inexpensive and minimally disruptive observation methods. Imagery collected by drones can be rapidly analysed using computer vision techniques to extract information, including behaviour classification, habitat analysis and identification of individual animals. While computer vision techniques can rapidly analyse drone‐collected data, the success of these analyses often depends on careful mission planning that considers downstream computational requirements—a critical factor frequently overlooked in current studies.
2. We present a comprehensive summary of research in the growing AI‐driven animal ecology (ADAE) field, which integrates data collection with automated computational analysis focused on aerial imagery for collective animal behaviour studies. We systematically analyse current methodologies, technical challenges and emerging solutions in this field, from drone mission planning to behavioural inference. We illustrate computer vision pipelines that infer behaviour from drone imagery and present the computer vision tasks used for each step. We map specific computational tasks to their ecological applications, providing a framework for future research design.
3. Our analysis reveals AI‐driven animal ecology studies for collective animal behaviour using drone imagery focus on detection and classification computer vision tasks. While convolutional neural networks (CNNs) remain dominant for detection and classification tasks, newer architectures like transformer‐based models and specialized video analysis networks (e.g. X3D, I3D, SlowFast) designed for temporal pattern recognition are gaining traction for pose estimation and behaviour inference. However, reported model accuracy varies widely by computer vision task, species, habitats and evaluation metrics, complicating meaningful comparisons between studies.
4. Based on current trends, we conclude semi‐autonomous drone missions will be increasingly used to study collective animal behaviour. While manual drone operation remains prevalent, autonomous drone manoeuvrers, powered by edge AI, can scale and standardise collective animal behavioural studies while reducing the risk of disturbance and improving data quality. We propose guidelines for AI‐driven animal ecology drone studies adaptable to various computer vision tasks, species and habitats. This approach aims to collect high‐quality behaviour data while minimising disruption to the ecosystem.publishe
Programmable synthetic magnetism and chiral edge states in nano-optomechanical quantum Hall networks
No full textArtificial magnetic fields break time-reversal symmetry in engineered materials—also known as metamaterials, enabling robust, topological transport of neutral excitations, much like edge channels facilitate electronic conduction in the integer quantum Hall effect. We experimentally demonstrate the emergence of quantum-Hall-like chiral edge states in optomechanical resonator networks. Synthetic magnetic fields for phononic excitations are induced through laser drives, while cavity optomechanical control allows full reconfigurability of the effective metamaterial response of the networks, including programming of magnetic fluxes in multiple resonator plaquettes. By tuning the interplay between network connectivity and magnetic fields, we demonstrate both flux-sensitive and flux-insensitive localized mechanical states. Scaling up the system creates spectral features that are precursors to Hofstadter butterfly spectra. Site-resolved spectroscopy reveals edge-bulk separation, with stationary phononic distributions signaling chiral edge modes. We directly probe those edge modes in transport measurements to demonstrate a unidirectional acoustic channel. This work unlocks new ways of controlling topological phononic phases at the nanoscale with applications in noise management and information processing.publishe
Using Saliency for Semantic Image Abstractions in Robotic Painting
No full textWe present an adaptive, semantics‐based abstraction approach that balances aesthetic quality and structural coherence within the practical constraints of robotic painting. We apply panoptic segmentation with color‐based over‐segmentation to partition images into meaningful regions aligned with semantic objects, while providing flexible abstraction levels. Automatic parameter selection for region merging is enabled by semantic saliency maps, derived from Out‐of‐Distribution segmentation techniques in combination with machine learning methods for feature detection. This preserves the boundaries of salient objects while simplifying less prominent regions. A graph‐based community detection step further refines the abstraction by grouping regions according to local connectivity and semantic coherence. The runtime of our method outperforms optimization‐based image vectorization methods, enabling the efficient generation of multiple abstraction levels that can serve as hierarchical layers for robotic painting. We demonstrate the quality of our method by showing abstraction results, robotic paintings with the e‐David robot, and a comparison to other abstraction methods.publishe
Absolutely continuous representing measures of moment functionals : the general truncated case
No full textpublishe
Coalitionary intra-group aggression by wild female bonobos
No full textIn humans and non-human primates, male aggression and physical violence are common strategies in the struggle over power and are efficient in exerting control over individuals and groups. In contrast, our close relative, the bonobo (Pan paniscus) is often described as an exceptionally peaceful primate due to the lack of lethal aggression or infanticide and the tendency for individuals to reconcile after conflicts. Nonetheless, rates of male aggression are high1, but, atypically for primates, bonobo females are observed to confront males without support from others. Despite female exogamy, forming coalitions of unrelated females in response to male aggression appears to be a common strategy, mostly involving charging or chasing and, in some cases, escalating to physical attacks2,3,4. Here, we report on a violent coalitionary attack by resident females against an adult male in a well-studied group of wild bonobos habituated to observation, detailing participants’ violent actions and the victim’s responses. The assault involved a fraction of the group, while almost everybody was present, and bystanders, including some close maternal kin, did not support the victim. Our observations detail a rare behavior that is not easy to reconcile with the assumed peaceful nature of bonobo society, but which contributes to evolutionary models of aggression5.publishe