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De-Emphasise, Aggregate, and Hide : A Study of Interactive Visual Transformations for Group Structures in Network Visualisations
No full textAnalysts often have to work with and make sense of large complex networks. One possible solution is to make visualisations interactive, providing users with a way to control visual clutter. Although several interactive methods have been proposed, there may be situations where some of them are too specific to be directly applicable. We have therefore identified several underlying low-level visual transformations, steered by group structures in the networks, and investigated their individual effects on user performance. This may both facilitate the development of further methods and support the generation of new hypotheses. We conducted an exploratory online experiment with 300 participants, involving five tasks, one control condition, and five group-based visual transformations: de-emphasising groups by opacity, position or size, aggregating groups, and hiding groups. The results for the three tasks that were specifically referring to groups show a high usage of the visual transformations by participants and several positive effects of the latter on accuracy, completion time, and mental effort spent. On the other hand, the two tasks that were not directly referring to groups show a lower usage of the visual transformations and the results regarding effects are rather mixedpublishe
Modern Times : A construction manual
No full textThis ‘construction manual’ tries to deal with the paradoxes inherent in so many attempts to define modernity: the try to construct themselves a foundation as a starting point of their own development, just to identify this base as void in retrospect. The solution to this paradox suggested here, however, does not call for the abandonment of modernity as a term or concept altogether, but for a revised conception of modernity: an understanding that does not define modernity as a starting or end point of development, but (only) as the respective present. In other words: we need a new form of history. The alternative advocated here is to understand historical time as a network of ‘chronoferences’, i.e. a history that is not about chronologically consistent development, but about temporal relations between present and absent times that are kept present by actors and practices. This could constitute a non-chronocentric form of history.publishe
Liegeplatzspezifischer Flächenverbrauch ausgewählter Bootsstationierungsanlagen an brandenburgischen Seen und Flussseen : Bericht der Arbeitsgruppe Umweltphysik am Limnologischen Institut der Universität Konstanz für das SuBoLakes-Projekt der Deutschen Bundesstiftung Umwelt (DBU), Az. 35825/01
No full textpublishe
Hamlet’s travels to postcolonial stages : Femi Osofisan’s Wẹ̀sóo, Hamlet! or the Resurrection of Hamlet and the Royal Shakespeare Company’s 2016 Hamlet
No full textEver since the putative performance of Hamlet aboard a ship of the British East India company off the coast of Sierra Leone in 1607, the African itineraries of Shakespeare’s play have largely been shaped by colonial, decolonial and postcolonial concerns. In the twenty-first century, William Shakespeare’s Hamlet has become saturated and problematized by its expansive travel histories. Authors, filmmakers and theatremakers can draw on a rich formal repertoire when reimagining Hamlet in today’s globalized, postcolonial contexts. Adopting a new formalist approach that analyses the political affordances of processes of transcultural adaptation, this chapter compares two recent examples that reset Hamlet in Africa: Nigerian playwright Femi Osofisan’s rewriting Wẹ̀sóo, Hamlet! or the Resurrection of Hamlet (2003–2017) and the Royal Shakespeare Company’s 2016 Hamlet production. It offers a case study of how the Shakespearean template has been transformed by its fusion with African ritualistic, theatrical and artistic elements. The productions share some notable similarities in their formal principles of adaptation but differ in their reflections on the political significance of Hamlet as a travelling tragedy in the postcolonial contexts of their production and reception.publishe
Mapping physiology : A systems biology approach for the development of alternative methods in toxicology
No full textChemical safety assessment still heavily relies on animal testing, which is associated with ethical dilemmas and has limited human predictive value. New approach methodologies (NAMs), including in vitro and in silico techniques, offer alternative solutions. In silico toxicology has made progress in predicting chemical effects but frequently lacks biological mechanistic foundations. Recent developments focus on the mechanistic understanding of adverse effects caused by chemicals, as embedded in (quantitative) adverse outcome pathways (AOPs). However, there is a demand for more detailed mechanistic insights at the gene and cell levels, encompassing both pathology and physiology. Drawing inspiration from the Disease Maps Project, this paper introduces physiological maps (PMs) as comprehensive graphical representations of biochemical processes related to specific organ functions. PMs are standardized using Systems Biology Graphical Notation (SBGN) and controlled vocabularies and annotations. Curation guidelines have been developed to ensure reproducibility and usability. We present the methodology used to build PMs, emphasizing the essential collaboration between domain experts and curators. PMs offer user-friendly, standardized visualization for data analysis and educational purposes. Enabling a better understanding of (patho)physiology, they also complement and support the development of AOPs by providing detailed mechanistic information at the gene and cell level. Furthermore, PMs contribute to developing in vitro test batteries and to building (dynamic) in silico models aiming to predict the toxicity of chemicals. Collaborative efforts between the toxicology and systems biology communities are crucial for creating standardized and comprehensive PMs, supporting and accelerating the development of human-relevant NAMs for next-generation risk assessment.publishe
Magnetization-Dependent Critical Current in S-(S/F)-S Junctions : Experimental Realization and Micromagnetic Simulation
No full textThe antagonistic properties of superconductors and ferromagnets open
up an attractive area of research for energy-efficient computing technologies. The remanent magnetization of ferromagnets, in particular,
offers potential for nonvolatile storage solutions. This thesis presents
the fabrication and investigation of ferromagnetically constricted superconducting junctions composed of aluminum and cobalt in an S-(S/F)-S
geometry.
Low-temperature transport measurements reveal that the critical current
of these junctions is strongly dependent on the magnetization state of
the ferromagnet, enabling the realization of a field-trainable, nonvolatile
superconducting switch. The persistence of the controllability in samples
with oxidized S/F interface suggests that the control mechanism is
predominantly mediated by stray fields. The inverse proximity effect,
driven by interfacial diffusion of Cooper pairs, manifests itself in a strong
influence on the critical current amplitude of the junction.
Micromagnetic simulations conducted in this thesis can replicate the
measured phenomenology semi-quantitatively using three-dimensional
micromagnetics and a purely stray-field dependent critical current model.
The simulations provide microscopic insight into the magnetization
dependence of the critical current, successfully replicating critical current
jumps in the experiment caused by Barkhausen jumps in the ferromagnet.
The results also demonstrate that the grain size of the polycrystalline
ferromagnet strongly impacts the observed phenomenology.publishe
Remote Research in Cognition and Perception
No full textA collection of articles on remote research in cognition and perception using the Internet for the Journal of Perceptual Imaging is presented. Four original articles cover the topics of exact versus conceptual replication of cognitive effects (e.g., mental accounting), effects of facial cues on the perception of avatars, cultural influences on perceptual image and video quality assessment, and how Internet habits influence social cognition and social cognitive research. The essentials of these articles are summarized here, and their contributions are embedded within a wider view and historical perspective on remote research in cognition and perception using the Internet.publishe
Heterochronic changes in gene expression underlie placental evolution in the fish family Poeciliidae
No full textPlacentas evolved nine times in the fish family Poeciliidae. Each time, the egg follicle is the maternal contribution to the placenta. In non-placental species, the follicle fully provisions the egg before fertilization. In placental species, provisioning continues throughout development, and the follicle becomes a more elaborate, well-vascularized organ. We generated transcriptomes for follicles from yolking eggs and developing embryos from two pairs of closely related placental and non-placental species that represent independent origins of placentation plus one non-placental outgroup. We identified genes expressed in eggs but not embryos of non-placental species that continue to be expressed during embryonic development in placental species. Their functions include the maternal transfer of nutrients and immunity. We then reconstructed the ancestral state of the non-placental common ancestor of each species pair and identified genes that were either upregulated or downregulated in developing embryos of placental species relative to non-placental species. These include clusters associated with lipid metabolism, immune response and tissue structure. The two placental lineages were convergent in the function of these genes, but few genes were in common between them. Thus, diverse gene regulatory changes converge on shared essential functions in the independent origins of a complex trait.publishe
Spatiotemporal differences in plastic biovectoring among three sympatric waterbirds
No full textAbiotic vectors of plastic and their impact in natural areas have been extensively studied, whereas biotic vectors have received less attention. Recent studies demonstrate that birds can act as powerful agents of plastic transport, moving large quantities of plastic from landfills to natural habitats through a process called biovectoring, causing pollution hotspots. While most studies have focused on single species, the present research broadens this approach. Here we compared the quantity, composition and spatio-temporal variation of plastic biovectoring among three co-existing waterbird species foraging on landfills near a coastal wetland: white storks, yellow-legged gulls, and lesser black-backed gulls in Cádiz Bay Important Bird Area (CBIBA; 152 km2), Spain. We analysed 177 regurgitated pellets (42–74 per species), weighed their plastic content and used FTIR-technology to identify and classify polymer composition. We then characterized each plastic item by shape, size and colour, enabling interspecific comparisons using multiple correspondence analysis. Finally, we combined census, GPS data and the plastic obtained from the pellets to develop a daily plastic loading model for each species. We found that white storks transported the most plastic per pellet (0.14 g by median), compared to 0.034 g for yellow-legged and 0.026 g for lesser black-backed gulls. In general, gulls carried similar types of plastic items, with more film and larger sizes than storks. In total, 531 kg of plastics were estimated to be biovectored into the CBIBA from landfills in 2022, with deposition being higher in winter and lesser black-backed gulls transporting about 54 % of the total, followed by yellow-legged gulls with 30 % and white storks with 16 %. In addition, we also identified major seasonal and spatial differences among species. Our results highlight the importance of using a multi species approach to plastic biovectoring, which is essential to understand and estimate its environmental impact, and to inform management strategies.publishe
Interventions to reduce bureaucratic discrimination: a systematic review of empirical behavioural research
No full texthe reality of street-level discretion can entail discrimination against people based on their identifiable characteristics. However, there has been surprisingly little systematic assessment of empirical evidence about what can be done to tackle the problem. This paper systematically reviews empirical behavioural research studies (N = 53) on the effects of interventions to reduce bureaucratic discrimination. Evidence shows that three types of interventions are reliably effective: outreach to and engagement with clients, anti-bias training, and passive representation. Inclusive practices can also reduce discrimination. These effects are however context-dependent, and causal mechanisms linking interventions with effects remain a ‘black box’.publishe