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Co-fabricating the permanent to enable temporary organizing: Insights from an ethnography of emergency response operations
No full textResearch on temporary organizations such as projects acknowledges the interplay between the temporary and the permanent. However, we still lack deeper understanding of the processes responsible for (re)producing and transforming permanent structures for temporary organizing. We present an ethnography of collaborative emergency response operations in a major German city – a setting providing an example of temporary organizing including more permanent structures drawn from intra- and interorganizational processes. Revealing the recursive interplay between the permanent and temporary across multiple levels, we explore practices of temporary organizing in situations that require both routine and highly situated responses. We also show how more permanent structures are co-fabricated in the process of temporary organizing. Furthermore, our study addresses the intricate interplay between organizing for the temporary and the permanent in relation to the tensions associated with the duality of stability and change. Finally, we outline implications for the effectiveness of emergency management and planning
Role of restraints on hydrogen atoms in Hirshfeld atom refinement: the case of tri-aspartic acid trihydrate
No full textTwo polymorphs of L-Asp-L-Asp-L-Asp (DDD) trihydrate as model compounds for biologically important proton-shuttle reactions were investigated with the quantum-crystallographic refinement technique Hirshfeld atom refinement (HAR). With HAR, hydrogen-atom positions are refined freely against the X-ray diffraction data and yield X—H bond distances close to those from neutron diffraction. However, the X-ray data of DDD trihydrate do not contain sufficient information to refine anisotropic displacement parameters (ADPs) for the hydrogen atoms, although the data quality is comparable to that of typical oligopeptide or protein datasets, including those with disordered fragments. Therefore, the following restraints were tested for the hydrogen-atom ADPs using NoSpherA2/olex2.refine: a restraint that approximates isotropic behaviour (ISOR), a restraint that enforces similar movement in any direction (SIMU), a rigid-bond restraint (DELU) and an advanced rigid-bond restraint (RIGU). Although it was found that there is no significant influence of the restraint weights and corresponding ADP values on the X—H distances, some recommendations on hydrogen-atom ADP restraint weights to be used in HAR are given. For ISOR, the suggested values are 10 times smaller (stricter) than the default values for non-hydrogen atoms in independent atom model (IAM) refinements, whereas those for RIGU are suggested to be less strict
Untersuchungen über die Wirkung der neuen Baldrianpräparate bei Erregungszuständen des Hundes
No full textDigitalisat der Ausgabe von 1920, erschienen 202
Character Varieties for Seifert Groups and Higgs Bundles over Orbifolds
No full textThis PhD thesis investigates Hodge structures on a particular class of complex algebraic varieties known as character varieties. Our objective is to integrate a powerful result stemming
from motivic integration and the proofs of the Weil conjectures, with classical representation-theoretic point-counting techniques. In this work, we develop a hybrid approach combining
arithmetic and geometric methods to compute the Deligne-Hodge polynomials of SL2 (C)-
character varieties associated with the fundamental group of a circle bundle - referred to as
a Seifert group - over an orbifold with a single ramified point. Additionally, using an orbifold
version of the non-abelian Hodge correspondence, we derive certain topological properties of
the moduli space of trace-free Higgs bundles, with fixed determinant, over the same base orbifold
The salty tango of brine composition and UV photochemistry effects on Halobacterium salinarum cell envelope biosignature preservation
No full textHypersaline environments, including brines and brine inclusions of evaporite crystals, are currently of great interest due to their unique preservation properties for the search for terrestrial and potentially extraterrestrial biosignatures of ancient life. However, much is still unclear about the specific effects that dictate the preservation properties of brines. Here we present the first insights into the preservation of cell envelope fragments in brines, characterizing the relative contributions of brine composition, UV photochemistry, and cellular macromolecules on biosignature preservation. Cell envelopes from the model halophile Halobacterium salinarum were used to simulate dead microbial cellular remains in hypersaline environments based on life as we currently know it. Using different Early Earth and Mars analogue brines, we show that acidic and NaCl-dominated brine compositions are more predisposed to preserving complex biosignatures from UV degradation, but that the composition of the biological material also influences this preservation. Furthermore, a combinatory effect between chaotropicity and photochemistry occurs, with the relative importance of each being brine-specific. These results provide an experimental framework for biosignature detection in hypersaline environments, emphasizing the need for laboratory simulations to evaluate preservation properties of each potential brine environment, on Earth and elsewhere in the solar system
ADA: A decoding algorithm for temporally-variable brain responses
No full textDecoding mental contents from brain activity is a long-standing goal in theoretical neuroscience and neural engineering. While current methods perform well in tasks with externally timed events, such as perception or motor execution, decoding covert cognitive processes like imagery or memory recall remains challenging due to uncertainty in the timing of underlying neural dynamics. In these settings, neurophysiological responses are not reliably linked to observable behaviour and likely vary in latency across trials. This complicates the use of time-locked analysis techniques, which perform decoding time point by time point across trials, thus assuming consistent signal timing. This problem corresponds to an understudied class of supervised learning where input features may be effectively mislabelled and need to be aligned across cases. To address this, we present the Adaptive Decoding Algorithm (ADA), a nonparametric method based on a two-level prediction. First, we estimate, for each trial, the temporal window most likely to reflect task-relevant signals; second, we decode the test trials based on the selection of informative windows. Using controlled simulations as well as a model of memory recall based on real perception data, we show that ADA outperforms alternative methods that assume fixed temporal structure. These results provide evidence that explicitly accounting for trial-specific timing can substantially improve decoding performance when the timing of relevant neural activity is unknown
Shrinking lakes, growing concerns: exploring perceptions of lake level decline as a prism for understanding socionatural hazards
No full textGroß Glienicker Lake and Sacrower Lake are two lakes in the Berlin-Brandenburg region that are facing significant challenges due to declining water levels associated with climate change. In this paper, we report on a study that employed a mixed-method approach, incorporating ethnographic research, a household survey and stakeholder workshops, to address: (1) public and stakeholder perceptions of these declining lake levels (2) the social structures that interact with these perceptions, (3) the willingness to act and perceptions of responsibility, and (4) the local practices for dealing with these challenges. Our analysis reveals that lake level loss offers a prism through which such a hazard becomes visible and understandable as shaped by the interdependence of natural and social processes. From this understanding, we develop possible paths forward in governing risks adaptively. Such an expanded understanding of lake level loss as a socionatural hazard enables the orchestration of more comprehensive solutions to such phenomena than is possible solely on the basis of technical remedies to such hazards
Pre-stimulation of precision-cut bovine udder slices with zymosan before LPS exposure indicates aspects of trained immunity especially in the absence of FCS
No full textMastitis in cattle poses a significant health challenge and results in substantial economic losses for the dairy industry. This study aimed to extend the existing precision-cut bovine udder slices (PCBUS) model as an in vitro model to explore the potential of inducing trained immunity in the udder with the goal to use the resulting knowledge for potential new treatment strategies. Interestingly, incubation of PCBUS with 10% fetal calf serum (FCS), but no 2% or FCS-free, negatively affected the production of some of the chemokines/cytokines analysed. When trained immunity was induced by zymosan, followed by stimulation with E. coli -derived lipopolysaccharide (LPS), production of interleukin (IL)-1β, IL-6, tumor necrosis factor α and interferon (IFNγ) was downregulated while production of IL-17A and pro-resolving lipid mediators (leukotrienes and prostaglandins) was upregulated. While the current experimental setup did not definitively confirm the induction of trained immunity for all parameters analysed in PCBUS, it validated the utility of PCBUS as a robust in vitro model for studying bovine udder inflammation. This model offers a promising platform for developing innovative mastitis treatments, particularly given the growing concern over antimicrobial resistance, as well as offering alternatives to the use of live animals in experimental studies in line with the 3Rs principles. It also provides a valuable tool for advancing our understanding of immune responses in the bovine udder. By adapting the precision-cut tissue slice technique to bovine udders, this model enables extensive research into new therapeutic approaches and supports basic research efforts to characterise complex pathophysiological processes associated with mastitis. Furthermore, our data highlight the potential limitations of FCS in in vitro studies. Our data should not only stimulate the discussion about FCS in homologues or heterologues species, but should also be kept in mind regarding the need for foetal calves to generate FCS in line with the 3Rs guideline
Komplementbindung beim Rotz durch das Kälteverfahren
No full textDigitalisat der Ausgabe von 1921, erschienen 202
Morality, Language, and Politics: An Analysis of the Relationship Between Political Attitudes and Metaphorical Concepts from the Perspective of Moral-Politics-Theory Based on Focus Group Interviews
No full textMenschliche Kognition wird fundamental durch konzeptuelle Metaphern geprägt. Diese beschreiben die Übertragung von Eigenschaften zwischen Konzepten und lassen sich anhand der Sprache untersuchen. Auch das Denken und Sprechen über Politik wird durch zahlreiche konzeptuelle Metaphern strukturiert. Die Moral-Politics-Theory definiert diese Metaphern und weist sie zwei Modellen zu, die ein konservatives beziehungsweise
progressives Weltbild begründen. Diese Studie untersucht anhand von
Fokusgruppeninterviews, inwiefern sich der von der Moral-Politics-Theory postulierte Zusammenhang von Metapherngebrauch und politischer Einstellung feststellen lässt. Zudem überprüft die Arbeit im Rahmen der Analyse, ob aus den von Fokusgruppenteilnehmer:innen gebrauchten konzeptuellen Metaphern zwei Gruppen hervorgehen, die den Modellen der Moral-Politics-Theory entsprechen. Methodisch wird dies durch eine strukturierende Metaphernanalyse umgesetzt, deren Ergebnisse quantifiziert und ausgewertet werden. Die Auswertung zeigt, dass ein Zusammenhang zwischen politischer Einstellung und Metapherngebrauch besteht, dieser bei konservativen Teilnehmer:innen jedoch stärker und bei progressiven Teilnehmer:innen nicht signifikant ausfällt. Zudem entsprechen die festgestellten Metapherngruppen weitestgehend den Modellen der Theorie. Die Studie bestätigt die Relevanz konzeptueller Metaphern für die politische Kommunikation und macht einige Vorschläge wie bestimmte Aspekte der Moral-Politics-Theory sowie deren Verbindung zu politischer Ideologie spezifiziert und weitergehend untersucht werden könnten.Human cognition is fundamentally shaped by conceptual metaphors. These metaphors describe the transfer of properties between concepts and can be examined through language. Thinking and speaking about politics is likewise structured by numerous conceptual metaphors. Moral Politics Theory defines these metaphors and assigns them to two models that underlie a conservative or progressive worldview.
This study uses focus group interviews to investigate the extent to which the relationship between metaphor use and political orientation, as postulated by Moral Politics Theory, can be observed. In addition, the analysis examines whether the conceptual metaphors used by focus group participants give rise to two groups corresponding to the models proposed by the theory. Methodologically, this is implemented through a structured metaphor analysis whose results are quantified and evaluated.
The findings show that there is a relationship between political orientation and metaphor use, although this relationship is stronger among conservative participants and not significant among progressive participants. Moreover, the identified metaphor groups largely correspond to the theory’s models. The study confirms the relevance of conceptual metaphors for political communication and offers several suggestions for how specific aspects of Moral Politics Theory and its connection to political ideology could be refined and further explored