ABSTRACT
Insights on stellar surface large-scale magnetic field topologies are usually drawn by applying Zeeman–Doppler Imaging (ZDI) to the observed spectropolarimetric time series. However, ZDI ...requires experience for reliable results to be reached and is based on a number of prior assumptions that may not be valid, e.g. when the magnetic topology is evolving on time-scales comparable to or shorter than the time span over which observations are collected. In this paper, we present a method based on Principal Component Analysis (PCA) applied to circularly polarized (Stokes V) line profiles of magnetic stars to retrieve the main characteristics of the parent large-scale magnetic topologies, like for instance, the relative strength of the poloidal and toroidal components, and the degree of axisymmetry of the dominant field component and its complexity (dipolar or more complex). We show that this method can also be used to diagnose the temporal variability of the large-scale magnetic field. Performing best for stars with moderate projected equatorial velocities hosting relatively simple magnetic field topologies, this new method is simpler than ZDI, making it convenient to rapidly diagnose the main characteristics of the large-scale fields of non-degenerate stars and to provide insights into the temporal evolution of the field topology.
One of the enduring puzzles in biology and the social sciences is the origin and persistence of intraspecific cooperation and altruism in humans and other species. Hundreds of theoretical models have ...been proposed and there is much confusion about the relationship between these models. To clarify the situation, we developed a synthetic conceptual framework that delineates the conditions necessary for the evolution of altruism and cooperation. We show that at least one of the four following conditions needs to be fulfilled: direct benefits to the focal individual performing a cooperative act; direct or indirect information allowing a better than random guess about whether a given individual will behave cooperatively in repeated reciprocal interactions; preferential interactions between related individuals; and genetic correlation between genes coding for altruism and phenotypic traits that can be identified. When one or more of these conditions are met, altruism or cooperation can evolve if the cost‐to‐benefit ratio of altruistic and cooperative acts is greater than a threshold value. The cost‐to‐benefit ratio can be altered by coercion, punishment and policing which therefore act as mechanisms facilitating the evolution of altruism and cooperation. All the models proposed so far are explicitly or implicitly built on these general principles, allowing us to classify them into four general categories.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Enriched environmental (EE) housing dampens stress-induced alterations in neurobiological systems, promotes adaptability, and extinguishes submissive behavioral traits developed during social defeat ...stress (SD). In the present study, we hypothesized that enrichment before SD can confer stress resiliency and, furthermore, that neuronal activity in the prefrontal cortex (PFC) is requisite for this resiliency. To test these hypotheses, mice were housed in EE, standard (SE), or impoverished (IE) housing and then exposed to SD. EE conferred resilience to SD as measured in several behavioral tasks. EE-housed mice expressed elevated FosB/ΔFosB immunostaining in areas associated with emotional regulation and reward processing, i.e., infralimbic, prelimbic, and anterior cingulate cortices, amygdala, and nucleus accumbens, and this expression was mostly preserved in mice receiving EE followed by SD. In contrast, in SE- or IE-housed animals, SD increased maladaptive behaviors and greatly reduced FosB/ΔFosB staining in the forebrain. We tested the putative involvement of the PFC in mediating resilience by lesioning individual regions of the PFC either before or after EE housing and then exposing the mice to SD. We found that discrete lesions of the infralimbic but not prelimbic or cingulate cortex made before but not after EE abolished the behavioral resiliency to stress afforded by EE and attenuated FosB/ΔFosB expression in the accumbens and amygdala while increasing it in the paraventricular hypothalamic nucleus. These data suggest that pathological ventromedial PFC outputs to downstream limbic targets could predispose an individual to anxiety disorders in stressful situations, whereas enhanced ventromedial PFC outputs could convey stress resilience.
Classical statistical theoryhypothesis testing, estimation, and the design of experiments and sample surveysis mainly the creation of two men: Ronald A. Fisher (1890-1962) and Jerzy Neyman ...(1894-1981). Their contributions sometimes complemented each other, sometimes occurred in parallel, and, particularly at later stages, often were in strong opposition. The two men would not be pleased to see their names linked in this way, since throughout most of their working lives they detested each other. Nevertheless, they worked on the same problems, and through their combined efforts created a new discipline.This new book by E.L. Lehmann, himself a student of Neymans, explores the relationship between Neyman and Fisher, as well as their interactions with other influential statisticians, and the statistical history they helped create together. Lehmann uses direct correspondence and original papers to recreate an historical account of the creation of the Neyman-Pearson Theory as well as Fishers dissent, and other important statistical theories.
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FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We examined whether cells of the adaptive immune system retain the memory of psychosocial stress and thereby alter mood states and CNS function in the host. Lymphocytes from mice undergoing chronic ...social defeat stress or from unstressed control mice were isolated and adoptively transferred into naive lymphopenic Rag2(-/-) mice. Changes in affective behavior, hippocampal cell proliferation, microglial activation states, and blood cytokine levels were examined in reconstituted stress-naive mice. The mice receiving lymphocytes from defeated donors showed less anxiety, more social behavior, and increased hippocampal cell proliferation compared with those receiving no cells or cells from unstressed donors. Mice receiving stressed immune cells had reduced pro-inflammatory cytokine levels in the blood relative to the other groups, an effect opposite to the elevated donor pro-inflammatory cytokine profile. Furthermore, mice receiving stressed immune cells had microglia skewed toward an anti-inflammatory, neuroprotective M2-like phenotype, an effect opposite the stressed donors' M1-like pro-inflammatory profile. However, stress had no effect on lymphocyte surface marker profiles in both donor and recipient mice. The data suggest that chronic stress-induced changes in the adaptive immune system, contrary to conferring anxiety and depressive behavior, protect against the deleterious effects of stress. Improvement in affective behavior is potentially mediated by reduced peripheral pro-inflammatory cytokine load, protective microglial activity, and increased hippocampal cell proliferation. The data identify the peripheral adaptive immune system as putatively involved in the mechanisms underlying stress resilience and a potential basis for developing novel rapid-acting antidepressant therapies.
ABSTRACT
In this paper, we present an analysis of near-infrared spectropolarimetric and velocimetric data of the young M dwarf AU Mic, collected with SPIRou at the Canada–France–Hawaii telescope from ...2019 to 2022, mostly within the SPIRou Legacy Survey. With these data, we study the large- and small-scale magnetic field of AU Mic, detected through the unpolarized and circularly polarized Zeeman signatures of spectral lines. We find that both are modulated with the stellar rotation period (4.86 d), and evolve on a time-scale of months under differential rotation and intrinsic variability. The small-scale field, estimated from the broadening of spectral lines, reaches 2.61 ± 0.05 kG. The large-scale field, inferred with Zeeman–Doppler imaging from Least-Squares Deconvolved profiles of circularly polarized and unpolarized spectral lines, is mostly poloidal and axisymmetric, with an average intensity of 550 ± 30 G. We also find that surface differential rotation, as derived from the large-scale field, is ≃30 per cent weaker than that of the Sun. We detect the radial velocity (RV) signatures of transiting planets b and c, although dwarfed by activity, and put an upper limit on that of candidate planet d, putatively causing the transit-timing variations of b and c. We also report the detection of the RV signature of a new candidate planet (e) orbiting further out with a period of 33.39 ± 0.10 d, i.e. near the 4:1 resonance with b. The RV signature of e is detected at 6.5σ while those of b and c show up at ≃4σ, yielding masses of $10.2^{+3.9}_{-2.7}$ and $14.2^{+4.8}_{-3.5}$ M⊕ for b and c, and a minimum mass of $35.2^{+6.7}_{-5.4}$ M⊕ for e.
Objectif Évaluer l’efficacité et la tolérance de l’association à ratio fixe insuline degludec/liraglutide (IDegLira) chez des patients diabétiques de type 2 (DT2) insuffisamment contrôlés sous ...sulfonylurées (SU) seules ou associées à la metformine. Matériel et méthodes Les patients ont été randomisés pour recevoir IDegLira une fois par jour ou un placebo, en association à un SU ± metformine. Les doses initiales étaient de 10 U d’insuline dégludec + 0,36 mg de liraglutide pour IDegLira avec une titration visant à obtenir une GAJ comprise entre 4,0 et 6,0 mmol/L. Résultats L’HbA1c moyenne a diminué de −1,5 % dans le groupe IDegLira et 0,5 % dans le groupe placebo (différence estimée DE : −1,02 % ; p < 0,001). La glycémie à jeun moyenne a diminué de 9,1 mmol/L (deux bras à l’inclusion) à 6,5 mmol/L dans le bras IDegLira et 8,8 mmol/L dans le bras placebo (DE -2,3 mmol/L ; p < 0,001). La dose moyenne d’IDegLira à S28 était de 28 doses unitaires (28 unités d’IDeg/1,0 mg Lira). Des hypoglycémies confirmées ont été observées chez respectivement 41,7 % et 17,1 % des patients traités par IDegLira et par placebo. La variation moyenne du poids corporel est de + 0,5 kg dans le groupe IDegLira versus −1,0 kg dans le groupe placebo (DE 1,48 kg ; p < 0,001). Discussion IDegLira a permis d’améliorer significativement le contrôle glycémique en association avec des SU. L’incidence des hypoglycémies était plus fréquente en comparaison à d’autres essais menés avec IDegLira, en raison de du maintien du SU.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
8.
Scapulafrakturen Lehmann L-J Prof Dr med; Schmalzl, J
Der Unfallchirurg,
01/2024, Volume:
127, Issue:
1
Journal Article
Peer reviewed
ZusammenfassungSkapulafrakturen stellen selten Verletzungen der oberen Extremität dar und erfordern unterschiedliche Behandlungsstrategien. Nichtdislozierte Frakturen und ein Großteil der ...Scapulablattfrakturen können konservativ versorgt werden; bei dislozierten Frakturen mit Beteiligung des Glenoids ist eine operative Versorgung zu erwägen. Dislozierte Glenoidfrakturen mit entsprechender Größe und intraartikulärer Stufenbildung sollten operativ behandelt werden. Verschiedene Klassifikationssysteme für Scapulafrakturen können die therapeutische Entscheidung unterstützen. Postoperativ und posttraumatisch sollte frühzeitig mobilisiert werden, um ein gutes funktionelles Ergebnis zu erzielen. Eindeutige Behandlungsempfehlungen auf Evidenzniveau liegen nicht vor; Langzeitergebnisse von Scapulafrakturen sind Gegenstand weiterer Untersuchungen. Bisher veröffentlichte Ergebnisse zeigen, je nach Fraktur, gute bis exzellente Resultate nach operativer und konservativer Behandlung. Individuelle Patientenfaktoren sind bei der Versorgung zu berücksichtigen.
A cornerstone result of sociobiology states that limited dispersal can induce kin competition to offset the kin selected benefits of altruism. Several mechanisms have been proposed to circumvent this ...dilemma but all assume that actors and recipients of altruism interact during the same time period. Here, this assumption is relaxed and a model is developed where individuals express an altruistic act, which results in posthumously helping relatives living in the future. The analysis of this model suggests that kin selected benefits can then feedback on the evolution of the trait in a way that promotes altruistic helping at high rates under limited dispersal. The decoupling of kin competition and kin selected benefits results from the fact that by helping relatives living in the future, an actor is helping individuals that are not in direct competition with itself. A direct consequence is that behaviours which actors gain by reducing the common good of present and future generations can be opposed by kin selection. The present model integrates niche‐constructing traits with kin selection theory and delineates demographic and ecological conditions under which altruism can be selected for; and conditions where the ‘tragedy of the commons’ can be reduced.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The medial prefrontal cortex (mPFC) plays a key role in top-down control of the brain's stress axis, and its structure and function are particularly vulnerable to stress effects, which can lead to ...depression in humans and depressive-like states in animals. We tested whether chronic social defeat produces structural alterations in the mPFC in mice. We first performed a microarray analysis of mPFC gene expression changes induced by defeat, and biological pathway analysis revealed a dominant pattern of down-regulation of myelin-associated genes. Indeed, 69% of the most significantly down-regulated genes were myelin-related. The down regulation was confirmed by in situ hybridization histochemistry for two strongly down-regulated genes, myelin oligodendrocyte glycoprotein (Mog) and ermin (Ermn), and by immunohistochemistry for myelin basic protein. To test for stress-induced changes in myelin integrity, aurophosphate (Black Gold) myelin staining was performed on mPFC sections. Quantitative stereologic analysis showed reduced myelinated fiber length and density. Behavioral analysis confirmed that the 14-day social defeat sessions resulted in induction of depressive-like states measured in social interaction and light/dark tests. The combined data suggest that chronic social defeat induces molecular changes that reduce myelination of the prefrontal cortex, which may be an underlying basis for stress-induced depressive states.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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