University of Konstanz
  • Konstanz, Germany
Recent publications
In this essay, we work over the imageries of exoplanetary exploration in digital games, observing their connections with concepts from media theories and science fiction studies. This articulation aims to comprehend how, in a philosofictional manner, games fictionally extrapolate the conditions of possibility for astronomical observation, allegorizing a series of contemporary themes regarding the technoscientific knowledge of space and planetary systems. As an analytical procedure, we observe game assets, images, and design dynamics, articulating them theoretically in three axes: technoscientific paraphernalia, compared planetology, and oblique orbits. With this, we understand how games can creatively approach (and, in the light of science fiction, extrapolate) contemporary relationships between science, technology, and society.
Magnesium silicate (MS) cement, which uses magnesium silicate hydrate (M-S-H) as its primary binding phase, is a promising low-carbon alternative to Portland cement. However, the slow dissolution of MgO limits the release of Mg ions, which is critical for the formation of M-S-H. To address this issue, solubilizers that complex Mg²⁺ and promote MgO dissolution have been proposed, provided that they do not significantly hinder M-S-H formation. This study systematically examined the effects of four anionic additives—acetate, citrate, orthophosphate, and carbonate—on M-S-H nucleation and early growth, developing a highly reproducible crystallization scenario. The observed reduction in supersaturation at the nucleation point for specific additive concentrations suggests that Mg-anion complexes may play an active role in M-S-H nucleation, potentially allowing M-S-H to form at lower supersaturation levels, which could be beneficial for MS cement applications. However, as shown here, additives such as citrate, while not inhibiting nucleation, can significantly slow the growth of M-S-H, potentially compromising the strength development of MS cement. Among the additives studied, moderate concentrations of phosphate and carbonate show the most promise, as they have minimal effects on the formation process while potentially reducing the supersaturation for M-S-H nucleation. Although further research is necessary to fully understand the effects of these anions, this study provides valuable insights into their impact on M-S-H nucleation and early growth.
Steep declines in Arctic skua populations in the southern extent of their breeding range have been reported during the last half of the 20th century. We used 24 yr of ringing and reencounter data from the Faroe Islands, North Atlantic, to investigate if patterns in survival probabilities can be explained by large-scale climatic events. Having first determined the migratory phenology and wintering regions, we estimated the effects of the North Atlantic Oscillation (NAO) index on survival during breeding and the Oceanic Niño index (ONI) during the non-breeding period within a capture–mark–recapture framework. Temporal trends along with direct and time-lagged effects of the environment on annual survival were modelled. We found support for a substantial decrease in adult annual survival, from ca. 0.93 in 1985 to ca. 0.77 in 2008, and weak support for a decrease in young (first year) survival over the duration of the study period. Furthermore, models indicated increased young survival following an El Niño winter. We suggest this time-lagged effect reflects downstream propagation of environmental conditions, particularly food availability, or a potential carry-over effect of El Niño conditions positively impacting the performance of the parents in the subsequent breeding season, leading to improved young survival prospects. While adult mortality cannot be attributed to the oceanic climate oscillations tested here, the negative trend in survival may account for the substantial population declines observed over the last decades.
Zusammenfassung Trotz laufender Gerichtsverfahren und der Einstufung durch zahlreiche Verfassungsschutzämter als gesichert rechtsextrem konnte die AfD bei der vergangenen Europawahl erhebliche Zugewinne erzielen. Auch wenn die Partei mit 15,9 % das bislang höchste Ergebnis einer rechtsradikalen Partei bei einer bundesweiten Wahl erzielt hat, ist der elektorale Nährboden des Rechtsradikalismus in Deutschland historisch verwurzelt. Schon in den 1990er- und 2000er-Jahren bildete ein räumlich verwurzeltes rechtsautoritäres und nativistisches Wählerreservoir Grundlage für Wahlerfolge von rechtsradikalen und rechtsextremen Parteien wie DVU, NPD und Republikanern. Wir gehen in diesem Beitrag der Frage nach, inwiefern sich der geografisch variierende Wahlerfolg der AfD auch bei der Europawahl 2024 durch die frühere Unterstützung dieser Parteien erklären lässt. Neben einer Analyse auf Ebene der 400 Landkreise und kreisfreien Städte blicken wir gesondert kleinräumlich auf Sachsen und Baden-Württemberg. Die Ergebnisse zeigen, dass die AfD dort eine deutlich höhere Unterstützung erhält, wo in früheren Zeitperioden rechtsradikale Parteien überdurchschnittlich gut abschnitten. Allerdings erreicht die AfD in diesen Regionen anders als bei früheren Wahlen kaum signifikante Zugewinne. Dies könnte darauf hindeuten, dass die AfD ihr rechtsautoritäres und nativistisches Wählerreservoir inzwischen ausgeschöpft hat. Darüber hinaus deuten die Ergebnisse darauf hin, dass die AfD insbesondere in Gegenden mit größerem Anteil an Beschäftigten ohne akademischen Abschluss hohe Stimmengewinne einfahren konnte.
In the present study, we investigate whether negation interacts with the set of alternatives that are elicited by why-questions. More precisely, we examine whether negation modifies the so-called contrast-class (set of alternatives) in the same way as negation interacts with other constructions, such as focal elements in declarative sentences. To this end, we conducted a multiple forced-choice experiment on Italian and German why-questions in which we examined this interaction in broad and narrow focus conditions in the presence and absence of negation. The results indicate that in both languages, the presence of a narrow focus changes the set of alternatives of a why-question in comparison to a broad focus interpretation, even in the presence of negation. These findings show that focus guides the creation of alternatives. They further imply that the effect of negation on the set of alternatives is pragmatic because negation does not modify the truth-conditional value of the alternatives and it remains the same in the presence or absence of the narrow focus. The addition of negation turns a set of false contrasting propositions into a set of true contrasting propositions.
Manually coding behaviours from videos is essential to study animal behaviour but it is labour‐intensive and susceptible to inter‐rater bias and reliability issues. Recent developments of computer vision tools enable the automatic quantification of behaviours, supplementing or even replacing manual annotation. However, widespread adoption of these methods is still limited, due to the lack of annotated training datasets and domain‐specific knowledge required to optimize these models for animal research. Here, we present YOLO‐Behaviour, a flexible framework for identifying visually distinct behaviours from video recordings. The framework is robust, easy to implement, and requires minimal manual annotations as training data. We demonstrate the flexibility of the framework with case studies for event‐wise detection in house sparrow nestling provisioning, Siberian jay feeding, human eating behaviours and frame‐wise detections of various behaviours in pigeons, zebras and giraffes. Our results show that the framework reliably detects behaviours accurately and retrieve comparable accuracy metrics to manual annotation. However, metrics extracted for event‐wise detection were less correlated with manual annotation, and potential reasons for the discrepancy between manual annotation and automatic detection are discussed. To mitigate this problem, the framework can be used as a hybrid approach of first detecting events using the pipeline and then manually confirming the detections, saving annotation time. We provide detailed documentation and guidelines on how to implement the YOLO‐Behaviour framework, for researchers to readily train and deploy new models on their own study systems. We anticipate the framework can be another step towards lowering the barrier of entry for applying computer vision methods in animal behaviour.
Despite the recognized need to address the prevention of sexual violence against adolescents in Nigeria, significant research gaps persist in understanding the patterns, determinants, and impacts of such violence, particularly regarding regional variations and the specific developmental needs of adolescents across different stages. This study provides Nigerian regional prevalence estimates disaggregated by gender, rural/urban, and in/out-of-school populations, while also identifying socio-demographic and cultural determinants related to increased vulnerability. A cross-sectional survey was conducted in South-West Nigeria with a sample of 961 adolescents, targeting in- and out-of-school adolescents aged 13–17 years. Descriptive statistics and logistic regression analyses were performed.The prevalence of any form of SV since age 12 was 69.4%, with higher rates among out-of-school adolescents and boys. Non-contact abuse (63.2%), passive contact abuse (41.9%), and active contact abuse (28.7%) were the most common forms reported. Peers were the dominant perpetrators (77.1%), followed by other adults (27.9%). Being male (OR 2.033), older (OR 1.214 per year), involved in a romantic relationship (OR 2.731), and experiencing SV before age 12 (OR 4.622) were significant risk factors. Higher household wealth (OR 0.902 per asset) and emotional support from both parents (OR 0.413) were protective factors.This study highlights the high burden of SV against adolescents in Nigeria, with concerning patterns of male victimization and peer perpetration. The findings emphasize the need for comprehensive, evidence-based strategies addressing emotional support, social norms, power dynamics, and economic vulnerabilities to prevent and respond to this problem effectively.
The accelerating growth of scientific literature overwhelms our capacity to manually distil complex phenomena like molecular networks linked to diseases. Moreover, biases in biomedical research and database annotation limit our interpretation of facts and generation of hypotheses. ENQUIRE (Expanding Networks by Querying Unexpectedly Inter-Related Entities) offers a time- and resource-efficient alternative to manual literature curation and database mining. ENQUIRE reconstructs and expands co-occurrence networks of genes and biomedical ontologies from user-selected input corpora and network-inferred PubMed queries. Its modest resource usage and the integration of text mining, automatic querying, and network-based statistics mitigating literature biases makes ENQUIRE unique in its broad-scope applications. For example, ENQUIRE can generate co-occurrence gene networks that reflect high-confidence, functional networks. When tested on case studies spanning cancer, cell differentiation and immunity, ENQUIRE identified interlinked genes and enriched pathways unique to each topic, thereby preserving their underlying context specificity. ENQUIRE supports biomedical researchers by easing literature annotation, boosting hypothesis formulation, and facilitating the identification of molecular targets for subsequent experimentation.
A receding horizon control framework is coupled with a Luenberger observer to construct an output-based control input stabilizing parabolic equations. The actuators and sensors are indicator functions of small subdomains, representing localized actuation and localized measurements. It is shown that, for a class of explicitly given sets of actuators and sensors, we can guarantee the stabilizing property of the constructed input. Results of numerical simulations are presented validating the theoretical findings.
Functional imaging studies indicate that both the assessment of a person as untrustworthy as well as the assumption that a person has a sexually transmitted infection are associated with activation in regions of the salience network. However, studies are missing that combine these aspects and investigate the perceived trustworthiness of individuals previously assessed with high or low probability of a sexually transmitted infection. During fMRI measurements, 25 participants viewed photographs of people pre-classified as having high or low HIV probability and judged their trustworthiness. In a post-rating, stimuli were rated for trustworthiness, attractiveness and HIV probability. Persons pre-classified as HIV- in contrast to those pre-classified as HIV+ were rated more trustworthy and with lower HIV probability. Activation in medial orbitofrontal cortex was higher for those rated and pre-classified as HIV- than HIV+. Based on the individual ratings, but not the pre-classification, there was significantly higher activation in Insula, amygdala, anterior cingulate cortex and Nucleus accumbens in response to untrustworthy than to trustworthy faces. Activation of the salience network occurred when a person was judged as untrustworthy, but not according to a pre-classification. Activation in the medial orbitofrontal cortex, a structure associated with reward was enhanced when a person was perceived as trustworthy, and also when a person was pre-classified with low HIV probability. Our findings suggest that trustworthiness and HIV- perception have consistency across samples, while the perception of risk and associated activation of the salience network has restricted cross-sample consistency. Significance Statement Whether a person is trustworthy or might pose a risk to one’s own health must be decided in a few moments and based on limited characteristics. The salience network as an “alarm system” should be involved in these evaluative processes. This paper reports the results of neural activation in trustworthiness judgments of naturalistic stimuli of persons pre-categorized as HIV+ or HIV-. We find activation in medial orbitofrontal cortex for people evaluated as trustworthy and for people pre-categorized as HIV-. For people judged as untrustworthy, activation in insula, amygdala, anterior cingulate cortex and Nucleus accumbens is revealed. These findings suggest a safety signal in the medial orbitofrontal cortex and an involvement of the salience network in risk detection.
Narrative Exposure Therapy (NET) is a trauma-memory-focused psychotherapeutic intervention that is effective in treating PTSD and other forms of trauma-spectrum disorders across different cultural contexts. KIDNET is a safe and robust treatment variant of NET specifically tailored for children and adolescents as young as 7 years of age. It can be delivered in schools, communities, outpatient clinics, private practices, or even refugee camps and is scalable also in low-resource contexts. It has been shown to be feasible and acceptable for gender diverse and intersectional groups.
This study presents a numerical simulation approach to investigate singlet–triplet interconversion effects in organic materials with rigid molecular structures that facilitate the photogeneration of charge-separated (CS) states, such as zwitterions resulting from intramolecular electron transfer. Our approach enables the detailed modeling of electron and nuclear spin-dependent observables, including magnetic field-affected reaction yields (MARY) and chemically induced dynamic nuclear polarization (CIDNP). The equilibrium solution of the stochastic Liouville equation can be obtained with simple algebraic manipulation by noting the relationship between the Laplace transform of the density operator and the time-domain representation of the same operator. Experimental MARY and CIDNP data are modeled as functions of key external and internal system parameters, such as magnetic field strength, hyperfine interactions, and exchange couplings. This allows for exploring processes that are otherwise experimentally inaccessible, providing deeper insights into the spin dynamics of the photoinduced CS state. Understanding these interconversion processes is not only essential for the fundamental photochemistry studies but also for the rational design and development of novel organic materials for photovoltaics and photocatalysis. Our results demonstrate the significant impact of singlet–triplet interconversion on the overall efficiency of charge separation and recombination processes, highlighting the importance of spin dynamics in the design of next-generation organic photovoltaic materials.
Am I still able to climb the ladder? Aging accompanies changes in physical constitution and a higher risk of injuries. At the same time, the judgment of action opportunities needs to be highly adaptive to the given task setting. We examined older adults’ (n = 40) judgment tendencies in four different tasks by use of a detection theory approach. The tasks’ setting differed in their boundaries’ proximity to the actor with either proximal (e.g., judging one’s hand fit into an opening) or distal boundaries (e.g., judging the reachability of a distant object). The older participants showed significantly more liberal judgments in tasks with distal boundaries. Body awareness and alertness were associated with the extent of judgment disparity between setting types. Subsequently, we compared a gender- and education-matched subsample of the group (n = 24) to a younger sample (n = 24). Older participants’ judgment tendencies were significantly more extreme, with stronger under- or overestimations depending on the type of setting. We discuss potential links between more extreme judgments in older adults and higher reliance on learned patterns. Future research is needed to further unravel these setting-dependent behavioral differences and the factors contributing to more extreme judgment tendencies with growing age.
Oncogenic types of human papillomaviruses (HPVs) are major human carcinogens. The formation of a trimeric complex between the HPV E6 oncoprotein, the cellular ubiquitin ligase E6AP and the p53 tumor suppressor protein leads to proteolytic p53 degradation and plays a central role for HPV-induced cell transformation. We here uncover that E6AP silencing in HPV-positive cancer cells ultimately leads to efficient induction of cellular senescence, revealing that E6AP acts as a potent anti-senescent factor in these cells. Thus, although the downregulation of either E6 or E6AP expression also acts partially pro-apoptotic, HPV-positive cancer cells surviving E6 repression proliferate further, whereas they become irreversibly growth-arrested upon E6AP repression. We moreover show that the senescence induction following E6AP downregulation is mechanistically highly dependent on induction of the p53/p21 axis, other than the known pro-senescent response of HPV-positive cancer cells following combined downregulation of the viral E6 and E7 oncoproteins. Of further note, repression of E6AP allows senescence induction in the presence of the anti-senescent HPV E7 protein. Yet, despite these mechanistic differences, the pathways underlying the pro-senescent effects of E6AP or E6/E7 repression ultimately converge by being both dependent on the cellular pocket proteins pRb and p130. Taken together, our results uncover a hitherto unrecognized and potent anti-senescent function of the E6AP protein in HPV-positive cancer cells, which is essential for their sustained proliferation. Our results further indicate that interfering with E6AP expression or function could result in therapeutically desired effects in HPV-positive cancer cells by efficiently inducing an irreversible growth arrest. Since the critical role of the E6/E6AP/p53 complex for viral transformation is conserved between different oncogenic HPV types, this approach could provide a therapeutic strategy, which is not HPV type-specific.
We report on the emissive properties of two related bismuth complexes, LBiBr2 and LBi, with a monoanionic 2,6-diiminophenyl N,C,N pincer ligand L. The Bi(III) complex phosphoresces at 77 K, while...
The interconnecting links between individuals in an animal social network are often defined by discrete, directed behaviours, but where these are difficult to observe, a network link (edge) may instead be defined by individuals sharing a space at the same time, which can then be used to infer a social association. The method by which these associations are defined should be informed by the biological significance of edges, and therefore often vary between studies. Identifying an appropriate measure of association remains a challenge to behavioural ecologists. Here, we use automatically recorded feeder visit data from four bird systems to compare three methods to identify a social association: (1) strict time-window, (2) co-occurrence in a group, and (3) arrival-time. We tested the similarity of the resulting networks by comparing the repeatability and sensitivity of individuals’ social traits (network degree, strength, betweenness). We found that networks constructed using different methods but applying similar, ecologically relevant definitions of associations based on individuals’ spatio-temporal co-occurrence, showed similar characteristics. Our findings suggest that the different methods to construct animal social networks are comparable, but result in subtle differences driven by species biology and feeder design. We urge researchers to carefully evaluate the ecological context of their study systems when making methodological decisions. Specifically, researchers in ecology and evolution should carefully consider the biological relevance of an edge in animal social networks, and the implications of adopting different definitions.
Recent evidence shows that US politicians’ conception of honesty has undergone a bifurcation, with authentic but evidence-free “belief-speaking” becoming more prominent and differentiated from evidence-based “fact-speaking”. Here we examine the downstream consequences of those two ways of conceiving honesty by investigating user engagement with fact-speaking and belief-speaking texts by members of the US Congress on Twitter (now X). We measure the conceptions of honesty of a sample of tweets and replies using computational text processing, and check whether the conceptions of honesty in the tweets align with those in their replies. We find that the conceptions of honesty used in replies align with those of the tweets, suggesting a “contagion”. Notably, this contagion replicates under controlled experimental conditions. Our study highlights the crucial role of political leaders in setting the tone of the conversation on social media.
Aim Plant invasions are a global problem that requires studying plants and their environmental associations across native and introduced ranges. Location 2000 km transects in China, Europe and North America. Time Period June 2019–July 2020. Major Taxa Studied Japanese knotweed ( Reynoutria japonica ). Methods We surveyed 150 populations of Japanese knotweed, a noxious invader of the temperate zone, along 2000 km transects in native China and the introduced ranges of Europe and North America. Results We found that larger plants and denser populations in the introduced ranges were associated with shifts in leaf economy and chemical defences. Introduced knotweed populations had higher SLA but reduced leaf chlorophyll, lignin, C:N ratio and leaf toughness along with altered leaf tannins, flavonoids and alkaloids. We found three distinct multivariate knotweed phenotypes primarily in the introduced ranges, and two multivariate knotweed phenotypes mainly in native populations. Main Conclusions Decreased herbivore and pathogen impacts in introduced populations and changes in environmental associations indicate that enemy release and novel habitat conditions might have driven the emergence of novel ecological strategies in this global plant invader.
Melting 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...
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Abdoallah Sharaf
  • Department of Biology
Christoph Kleineidam
  • Department of Biology
Bernd Genser
  • Department of Economics
Susumu Shikano
  • Department of Politics and Public Administration
Gereon Wolters
  • Department of Philosophy
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Konstanz, Germany