A Broad Search for Counterrotating Gas and Stars: Evidence for Mergers and Accretion

We measure the frequency of bulk gas-stellar counterrotation in a sample of 67 galaxies drawn from the Nearby Field Galaxy Survey, a broadly representative survey of the local galaxy population down to M_B-15. We detect 4 counterrotators among 17 E/S0's with extended gas emission (24% +8 -6). In contrast, we find no clear examples of bulk counterrotation among 38 Sa-Sbc spirals, although one Sa does show peculiar gas kinematics. This result implies that, at 95% confidence, no more than 8% of Sa-Sbc spirals are bulk counterrotators. Among types Sc and later, we identify only one possible counterrotator, a Magellanic irregular. We use these results together with the physical properties of the counterrotators to constrain possible origins for this phenomenon.Comment: 19 pages, 4 figures, AJ, accepte

Secular evolution versus hierarchical merging: galaxy evolution along the Hubble sequence, in the field and rich environments

In the current galaxy formation scenarios, two physical phenomena are invoked to build disk galaxies: hierarchical mergers and more quiescent external gas accretion, coming from intergalactic filaments. Although both are thought to play a role, their relative importance is not known precisely. Here we consider the constraints on these scenarios brought by the observation-deduced star formation history on the one hand, and observed dynamics of galaxies on the other hand: the high frequency of bars and spirals, the high frequency of perturbations such as lopsidedness, warps, or polar rings. All these observations are not easily reproduced in simulations without important gas accretion. N-body simulations taking into account the mass exchange between stars and gas through star formation and feedback, can reproduce the data, only if galaxies double their mass in about 10 Gyr through gas accretion. Warped and polar ring systems are good tracers of this accretion, which occurs from cold gas which has not been virialised in the system's potential. The relative importance of these phenomena are compared between the field and rich clusters. The respective role of mergers and gas accretion vary considerably with environment.Comment: 18 pages, 8 figures, review paper to "Penetrating Bars through Masks of Cosmic Dust: the Hubble Tuning Fork Strikes a New Note", Pilanesberg, ed. D. Block et al., Kluwe

Linguistic politeness across Austria and Italy: Backing out of an invitation with an instant message

The study compares how native speakers of German from the area of Innsbruck (Austria) and native speakers of Italian from the area of Rome (Italy) perceive the communicative act of backing out of an invitation for dinner at the last minute, in a situation of low social distance. The purpose of the study is twofold: to shed light on the orientation of Austrian German and Italian languages/cultures in terms of linguistic politeness, and to expand empirical cross-cultural research to a less-commonly investigated speech act. Data collected by means of a discourse completion task (DCT) are triangulated with responses to an assessment question and metapragmatic comments, and analyzed following a quantitative approach. The analysis of the DCT findings shows some cross-group differences in the choice of speech act realization strategies and internal modifiers. However, the overall results reveal more similarities than differences between the two populations regarding the informants’ perception of face threat in last-minute cancellations. This seems to disprove the idea that the two groups belong to different cultural frameworks in terms of politeness orientation, at least as far as it concerns the specific speech act under investigation

P5526Reproducibility and spatial accuracy of magnetocardiographic source localization: a phantom study in an unshielded laboratory for interventional electrophysiology

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Metabarcoding Reveals a Potentially Undescribed Columnaris-Causing Bacterium in Peracute Skin Disease of Rainbow Trout (Oncorhynchus mykiss, Walbaum)

Columnaris-causing bacteria (CCB) represent a group of four Flavobacterium species, previously classified under Flavobacterium columnaris, causing a threatening condition in salmonid farming characterised by cutaneous and gill lesions, commonly referred to as ‘saddleback disease’. A peracute skin disease outbreak with high mortality in rainbow trout (Oncorhynchus mykiss) farms in Northern Italy was investigated. The disease presented with skin discoloration and scale lifting without internal organ abnormalities, leading to a weekly cumulative mortality of up to 80%. The disease was successfully managed with Oxytetracycline treatment, with no relapses observed. Conventional investigation methods produced inconsistent results, prompting additional analyses. Metagenomic sequencing of the 16S rRNA identified Flavobacterium species differing from the classical CCB based on the alignment of the V3 and V4 regions, with best matches to Flavobacterium bernardetii, Flavobacterium aquicola, and Flavobacterium hiemivividum. Histopathology and SEM confirmed epidermal necrosis and bacterial infiltration in the dermis, with filamentous bacteria resembling Flavobacterium morphology yet differing from classical CCB lesions. These findings point to a previously undescribed Flavobacterium-related skin disease with significant economic implications, supporting the value of metagenomic in investigating microbial dynamics in aquaculture diseases, especially in sites exposed to external environments. Further research is required to clarify the pathogenic mechanisms and guide effective management strategies for future outbreaks

The importance of the cellular stress response in the pathogenesis and treatment of type 2 diabetes

Organisms have evolved to survive rigorous environments and are not prepared to thrive in a world of caloric excess and sedentary behavior. A realization that physical exercise (or lack of it) plays a pivotal role in both the pathogenesis and therapy of type 2 diabetes mellitus (t2DM) has led to the provocative concept of therapeutic exercise mimetics. A decade ago, we attempted to simulate the beneficial effects of exercise by treating t2DM patients with 3 weeks of daily hyperthermia, induced by hot tub immersion. The short-term intervention had remarkable success, with a 1 % drop in HbA1, a trend toward weight loss, and improvement in diabetic neuropathic symptoms. An explanation for the beneficial effects of exercise and hyperthermia centers upon their ability to induce the cellular stress response (the heat shock response) and restore cellular homeostasis. Impaired stress response precedes major metabolic defects associated with t2DM and may be a near seminal event in the pathogenesis of the disease, tipping the balance from health into disease. Heat shock protein inducers share metabolic pathways associated with exercise with activation of AMPK, PGC1-a, and sirtuins. Diabetic therapies that induce the stress response, whether via heat, bioactive compounds, or genetic manipulation, improve or prevent all of the morbidities and comorbidities associated with the disease. The agents reduce insulin resistance, inflammatory cytokines, visceral adiposity, and body weight while increasing mitochondrial activity, normalizing membrane structure and lipid composition, and preserving organ function. Therapies restoring the stress response can re-tip the balance from disease into health and address the multifaceted defects associated with the disease

Magnetocardiographic evaluation of nonarrhythmogenic flecainide-induced electrocardiographic T-wave inversion

No abstract availabl

Depicting conformational ensembles of \u3b1-synuclein by single molecule force spectroscopy and native mass spectroscopy

Description of heterogeneous molecular ensembles, such as intrinsically disordered proteins, represents a challenge in structural biology and an urgent question posed by biochemistry to interpret many physiologically important, regulatory mechanisms. Single-molecule techniques can provide a unique contribution to this field. This work applies single molecule force spectroscopy to probe conformational properties of \u3b1-synuclein in solution and its conformational changes induced by ligand binding. The goal is to compare data from such an approach with those obtained by native mass spectrometry. These two orthogonal, biophysical methods are found to deliver a complex picture, in which monomeric \u3b1-synuclein in solution spontaneously populates compact and partially compacted states, which are differently stabilized by binding to aggregation inhibitors, such as dopamine and epigallocatechin-3-gallate. Analyses by circular dichroism and Fourier-transform infrared spectroscopy show that these transitions do not involve formation of secondary structure. This comparative analysis provides support to structural interpretation of charge-state distributions obtained by native mass spectrometry and helps, in turn, defining the conformational components detected by single molecule force spectroscopy