Defect-mediated turbulence in systems with local deterministic chaos

We show that defect-mediated turbulence can exist in media where the underlying local dynamics is deterministically chaotic. While many of the characteristics of defect-mediated turbulence, such as the exponential decay of correlations and a squared Poissonian distribution for the number of defects, are identical to those seen in oscillatory media, the fluctuations in the number of defects differ significantly. The power spectra suggest the existence of underlying correlations that lead to a different and non-universal scaling structure in chaotic media.Comment: 4 pages, 5 figure

From ballistic to Brownian vortex motion in complex oscillatory media

We show that the breaking of the rotation symmetry of spiral waves in two-dimensional complex (period-doubled or chaotic) oscillatory media by synchronization defect lines (SDL) is accompanied by an intrinsic drift of the pattern. Single vortex motion changes from ballistic flights at a well-defined angle from the SDL to Brownian-like diffusion when the turbulent character of the medium increases. It gives rise, in non-turbulent multi-spiral regimes, to a novel ``vortex liquid''.Comment: 5 pages, 4 figure

Spiral Waves in Chaotic Systems

Spiral waves are investigated in chemical systems whose underlying spatially-homogeneous dynamics is governed by a deterministic chaotic attractor. We show how the local periodic behavior in the vicinity of a spiral defect is transformed to chaotic dynamics far from the defect. The transformation occurs by a type of period doubling as the distance from the defect increases. The change in character of the dynamics is described in terms of the phase space flow on closed curves surrounding the defect.Comment: latex file with three postscript figures to appear in Physical review Letter

The power of shared embodiment: Renegotiating non/belonging and in/exclusion in an ephemeral community of care

In this article, we explore the power of shared embodiment for the constitution of an affective community. More specifically, we examine how people afflicted by long-term, arduous experiences of war, migration, and discrimination sensually articulate and, at least temporarily, renegotiate feelings of non/belonging, care, and in/exclusion. Methodologically, we draw on emplaced ethnography and systematic phenomenological go-alongs with a group of elderly migrants, born and raised in different parts of Vietnam, who had arrived in Germany within different legal–political frameworks and who, during the time of our psychological–anthropological research, frequented the same psychotherapeutic clinic. We apply the notion of “affective communities” (Zink in Affective Societies: Key Concepts. Routledge, New York, 2019) to grasp how the group experienced a sensual place of mutual belonging outside the clinic when moving through different public spaces in Berlin as part of their therapy. Particular attention is paid to the participants’ embodied and emplaced memories that were reactivated during these excursions. Shared sensations and spatiality, we argue, made them feel they belonged to an ephemeral community of care that was otherwise hardly imaginable due to their distinct individual biographies, contrasting political attitudes, and ties to different social collectives. In analyzing this affective community, we highlight how significant spatio-sensorial modes of temporal solidification can be in eliciting embodied knowledge that positively contributes to therapeutic processes

Standardisierbare Verfahren zur präuisen Charakterisierung des Absorptions-, Reflexions- und Tranmissionsgrads optischer Komponenten

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Zerrissene Zugehörigkeiten: Schweigen, Erinnern und Affekte in vietdeutschen Lebenswelten

Gerade in Krisenzeiten ist das Gefühl von Zugehörigkeit wichtig. Aber was, wenn die akute Krise eigentlich Jahrzehnte vergangen, das Gefühlte aber trotzdem so nah ist? Anhand dichter ethnografischer Einblicke stellt Edda Willamowski die Auswirkungen forcierter Migration aus einer Langzeitperspektive dar. Behutsam wird aufgezeigt, wie älter werdende Geflüchtete aus Vietnam, die als sogenannte Boat People ins kollektive Gedächtnis eingingen, sich heute verorten und wie vielschichtig Kriegs- und Nachkriegsvergangenheiten den Alltag durchdringen. Sie erläutert Mobilitätsphänomene als eine anhaltende Aushandlung gefühlter Beheimatung und sensibilisiert für die fundamentale Bedeutung von Schweigen und verkörperten Erinnerungen im gesellschaftlichen Zusammenleben

Bleeding with anticoagulants in emergency medicine

Hintergrund: Die Prävalenz von Erkrankungen, die einer Therapie mit Antikoagulanzien (AK) bedürfen, steigt im Zuge der alternden Gesellschaft, dabei nimmt der Marktanteil der Nicht-Vitamin-K-abhängigen oralen Antikoagulanzien (NOAK) gegenüber den Vitamin-K-Antagonisten (VKA) stetig zu. Daten zu optimaler Therapie und Outcome von Blutungskomplikationen sind rar, stammen aus klinischen Studien oder Analysen spezieller Patientengruppen, während die Notfall-medizin mit allen Ereignissen unabhängig von Indikation, Dosierung oder Art der Blutung kon-frontiert wird. Methodik: Es erfolgte eine retrospektive Analyse aller per automatisierter Abfrage identifizierter Blutungsereignisse unter AK, die in den Jahren 2014 und 2015 über die Notaufnahmen der Charité Campus Virchow Klinikum und Mitte stationär aufgenommen wurden. Ergebnisse: 284 eingeschlossene Fälle verteilten sich auf 166 Blutungen unter VKA, 71 unter NOAK (57 x Rivaroxaban, 9 x Dabigatran, 5 x Apixaban), 33 unter parenteraler (pAK) und 14 unter kombinierter AK (kAK). Die demographischen Daten, Komorbiditäten und Begleitmedikati-on waren relativ homogen. Dosierungsfehler waren häufig, eine adäquate AK zum Aufnahmezeit-punkt bestand in 41,7 % der Fälle (39,0 % VKA, 55,6 % NOAK, 33,3% pAK, 28,6 % kAK, p = 0,067). 47,4 % der NOAK-Blutungen traten unter reduzierten Dosisregimes auf. Es fanden sich 65,5 % Major-Blutungen ohne relevante Unterschiede zwischen den Gruppen (p = 0,642). Gastrointestinale Blutungen waren häufiger unter NOAK (42,3 % vs. 26,5 % VKA, 15,2 % pAK, 14,3% kAK, p = 0,011), intrakranielle Blutungen unter VKA (27,1 % vs. 5,6 % NOAK, 9,1 % pAK, 14,3 % kAK, p < 0,001). Blutprodukte wurden ähnlich oft in allen Gruppen transfundiert, invasive Diagnostik erfolgte in 40,4 % der Fälle, am häufigsten unter NOAK (56,3 %, p = 0,011), Operationen mit 23,6 % unter kAK (50 %, p < 0,001). PPSB (u./o. Vitamin K für VKA) als Antagonisierung wurde überwie-gend unter VKA verabreicht (66,3 % vs. 11,3 % NOAK, 0 % pAK, 28,6 % kAK, p < 0,001). Thromboembolische Komplikationen waren selten (3,2 %, p = 0,559). In 42,0 % kamen die Blu-tungen unter NOAK ohne Maßnahmen zum Stillstand (vs. 14,0 % VKA, 15,2 % pAK, 14,3 % kAK, p < 0,001). Die Krankenhausmortalität lag bei 6,5 % und war am höchsten unter VKA (7,9 % vs. 4,4 % NO-AK, 3,0 % pAK, 7,1 % kAK), ohne statistische Signifikanz zu erreichen (p = 0,613). Eine Entlas-sung in unverändertem Allgemeinzustand erfolgte häufiger nach Blutungen unter pAK und NOAK (60,6 % bzw. 45,6 %) als unter VKA oder kAK (29,9 % bzw. 28,6 %, p = 0,003). Schlussfolgerung: Notfallmedizinisch relevante Blutungen unter NOAK verliefen nicht schwerer oder tödlicher als unter VKA, sie kamen häufiger ohne Maßnahmen zum Stillstand, die Entlassung erfolgte öfter ohne Einschränkungen. Damit werden bisherige Studienergebnisse bestätigt. Sorge vor Blutungen sollte nicht zu Unterdosierung führen. Ob spezifische Antidota das Outcome weiter verbessern, müssen weitere Studien klären.Background: The prevalence of conditions requiring anticoagulation (AC) is increasing with an ageing population and the market share of non-vitamin-K-dependent oral anticoagulants (NOAC) compared to vitamin K antagonists (VKA) is steadily increasing. Data on optimal therapy and out-come of bleeding complications are scarce, originating from clinical trials or analyses of special patient groups, whereas emergency medicine is confronted with all events regardless of indication, dosage or type of bleeding. Methods: We performed a retrospective analysis of all bleeding events identified by automated query among anticoagulated patients who were admitted as inpatients via the emergency depart-ments of Charité Campus Virchow Klinikum and Mitte in 2014 and 2015. Results: 284 cases were distributed among 166 bleeding events with VKA, 71 NOAC (57 x riva-roxaban, 9 x dabigatran, 5 x apixaban), 33 parenteral (pAC) and 14 with combined AK (cAC). Demographics, comorbidities, and concomitant medications were relatively homogeneous. Dosage errors were common, with adequate AC at admission in 41.7% of cases (39.0% VKA, 55.6% NOAC, 33.3% pAC, 28.6% cAC, p = 0.067). 47.4% of NOAC bleeding occurred with reduced dose regimens. There were 65.5% major bleedings with no relevant differences between groups (p = 0.642). Gas-trointestinal bleeding was more frequent in patients treated with NOAC (42.3% vs. 26.5% VKA, 15.2% pAC, 14.3% cAC, p = 0.011), intracranial bleeding with VKA (27.1% vs. 5.6% NOAC, 9.1% pAC, 14.3% cAC, p < 0.001). Transfusion of blood products (red blood cells, platelets, fresh frozen plasma) was comparable between groups, invasive procedures were performed in 40.4% of cases, most frequently with NOAC (56.3%, p = 0.011), surgery in 23.6%, mainly with cAC (50%, p < 0.001). Prothrombin complex concentrates (and/or vitamin K for VKA) were predominantly administered with VKA (66.3 % vs. 11.3 % NOAC, 0 % pAC, 28.6 % cAC, p < 0.001). Thromboembolic complications were rare (3.2%, p = 0.559). Hemostasis was achieved without any intervention in 42.0% of Pa-tients receiving NOAC (vs. 14.0% VKA, 15.2% pAC, 14.3% cAC, p < 0.001). In-hospital mortality was 6.5% and highest with VKA (7.9% vs. 4.4% NOAC, 3.0% pAC, 7.1% cAC) though not reaching statistical significance (p = 0.613). Discharge in unchanged general con-dition was more frequent after bleeding in patients treated with pAC or NOAK (60.6 % and 45.6 %, respectively) than with VKA or cAC (29.9 % and 28.6 %, respectively, p = 0.003). Conclusion: There was no difference in severity nor fatality of bleeding events in patients treated with NOAC versus VKA. Achievement of hemostasis without intervention and unchanged medi-cal condition at discharge as compared to prior bleeding were found significantly more often in the NOAC-group. This confirms previous study results. Fear of bleeding should not lead to underdos-ing. If specific antidotes further improve outcome needs to be clarified in further studies

Lattice Gas Automata for Reactive Systems

Reactive lattice gas automata provide a microscopic approachto the dynamics of spatially-distributed reacting systems. After introducing the subject within the wider framework of lattice gas automata (LGA) as a microscopic approach to the phenomenology of macroscopic systems, we describe the reactive LGA in terms of a simple physical picture to show how an automaton can be constructed to capture the essentials of a reactive molecular dynamics scheme. The statistical mechanical theory of the automaton is then developed for diffusive transport and for reactive processes, and a general algorithm is presented for reactive LGA. The method is illustrated by considering applications to bistable and excitable media, oscillatory behavior in reactive systems, chemical chaos and pattern formation triggered by Turing bifurcations. The reactive lattice gas scheme is contrasted with related cellular automaton methods and the paper concludes with a discussion of future perspectives.Comment: to appear in PHYSICS REPORTS, 81 revtex pages; uuencoded gziped postscript file; figures available from [email protected] or [email protected]