Miracle-dz/UniFAR-FTUs huggingface dataset:
Influence de la rétroaction des étoiles sur la structure du milieu interstellaire à l'échelle galactique

La formation des etoiles, processus fondamental en astrophysique, resiste toujours a la comprehension. En effet, de nombreux phenomenes interagissent durant les differentes etapes, et ce sur une large gamme d’echelles. Il est donc primordial de comprendre la dynamique du milieu interstellaire, dans lequel les etoiles se forment. En particulier, il est maintenant bien etabli que la structure du milieu interstellaire est fortement impactee par des processus de retroaction de la part des etoiles qui s’y forment. D’une part cette retroaction limite le taux de formation de nouvelles etoiles, et d’autre part elle est l’un des contributeurs a la morphologie et la dynamique des galaxies : taille du disque, ejection de matiere, etc. Ce travail de these propose d’etudier numeriquement la dynamique du milieu interstellaire, de maniere a mettre en evidence l’impact des processus de retroaction. Le processus principal qui sera etudie est les supernovae, figurant parmi les evenements les plus energetiques dans le milieu interstellaire. Apres l’etude et la modelisation en detail de l’explosion d’une unique supernova dans nuage moleculaire, un modele numerique incluant formation d’etoiles et retroaction par supernovae sera presente et mis en œuvre dans des simulations d’un disque galactique stratifie a l’echelle du kiloparsec. Une extension de ce modele pour tenir compte du rayonnement ionisant sera proposee. Il est effectivement possible de reguler la formation d’etoiles a l’aide de modeles de retroaction par les supernovae, mais les resultats precis dependent de maniere significative des details du schema mis en œuvre. En utilisant la variante apparaissant comme la plus realiste, des simulations a haute resolution du milieu interstellaire sont presentees et etudiees. En particulier, il est possible de mettre en evidence des proprietes de la turbulence compressible et magnetisee a l’echelle galactique : variation des spectres de puissance en fonction de l’altitude, alignement spontane de la vitesse et du champ magnetique, effet antagoniste de la retroaction sur cet alignement et formation de structures.
Regional muscle loss after short duration spaceflight.

BACKGROUND Muscle strength and limb girth measurements during Skylab and Apollo missions suggested that loss of muscle mass may occur as a result of spaceflight. Extended duration spaceflight is important for the economical and practical use of space. The loss of muscle mass during spaceflight is a medical concern for long duration flights to the planets or extended stays aboard space stations. Understanding the extent and temporal relationships of muscle loss is important for the development of effective spaceflight countermeasures. HYPOTHESIS We hypothesized that significant and measurable changes in muscle volume would occur in Shuttle crewmembers following 8 d of weightlessness. METHODS MRI was used to obtain the muscle volumes of the calf, thigh and lower back before and after the STS-47 Shuttle mission. RESULTS Statistical analyses demonstrated that the soleus-gastrocnemius (-6.3%), anterior calf (-3.9%), hamstrings (-8.3%), quadriceps (-6.0%) and intrinsic back (-10.3%) muscles were decreased, p < 0.05, compared to baseline, 24 h after landing. At 2 weeks post recovery, the hamstrings and intrinsic lower back muscles were still below baseline, p < 0.05. CONCLUSIONS These results demonstrate that even short duration spaceflight can result in significant muscle atrophy.
Dynamics of yeast prion aggregates in single living cells

Prions are propagating proteins that are ordered protein aggregates, in which the phenotypic trait is retained in the altered protein conformers. To understand the dynamics of the prion aggregates in living cells, we directly monitored the fate of the aggregates using an on‐chip single‐cell cultivation system as well as fluorescence correlation spectroscopy (FCS). Single‐cell imaging revealed that the visible foci of yeast prion Sup35 fused with GFP are dispersed throughout the cytoplasm during cell growth, but retain the prion phenotype. FCS showed that [PSI+] cells, irrespective of the presence of foci, contain diffuse oligomers, which are transmitted to their daughter cells. Single‐cell observations of the oligomer‐based transmission provide a link between previous in vivo and in vitro analyses of the prion and shed light on the relationship between the protein conformation and the phenotype.
Algebraic properties of singular systems subject to decentralized output feedback

This paper investigates algebraic properties of decentralized singular systems (DSSs) under local static output feedback. New concepts of the geometric multiplicity (GM) of the finite decentralized fixed mode (DFM), the decentralized output feedback variable polynomial (DVP), and the finite decentralized output feedback cycle index (DCI) of the DSS are defined. The formulas for determining the GM and the DCI are given in terms of the DFM and the system matrices. It is shown that almost any decentralized output feedback can make the zeros of the DVP (i.e., the closed-loop poles that are variable) distinct and away from any given finite set in the complex plane. It is also shown that the finite DFM of the DSS are those uncontrollable and/or observable finite modes of the closed-loop DSS through any single channel. Finally, the minimal number of the inputs and outputs that guarantee the finite modes of the closed-loop DSS controllable and observable is shown to be the finite DCI of the DSS. An illustrative example is provided.
The Involvement of Endotoxin in Halothane‐associated Liver Injury

Since endotoxin, lipopolysaccharides (LPS), have been implicated as a causative factor in the development of hepatic necrosis in rats exposed to hepatotoxic levels of several chemical agents, the role of LPS in the halothane–hypoxia (HH) model of hepatic damage in male Sprague–Dawley rats was investigated. When injected intravenously immediately after halothane anesthesia, a subnecrotic dose of LPS (0.5 mg/kg; Escherichia coli 026:B6) was found to markedly potentiate HH-induced hepatic necrosis. Pretreatment of the animals with the antiendotoxin agent, lactulose, prior to exposure to halothane reduced the hepatic damage normally seen from HH. A possible mechanism of LPS-induced potentiation was indicated by changes in hepatic calcium levels at 24 h after treatment. Endogenous LPS may play a role in HH-induced hepatic necrosis, and the mechanism of LPS-induced potentiation may be due to an LPS-related membrane dysfunction.
Face and Eye-ware Classification using Geometric Features for a Data-driven Eye-ware Recommendation System

In this work we present an automatic shape extraction and classification method for face and eye-ware shapes. Our novel eye-ware shape extraction algorithm can extract the polygonal shape of eyeware accurately and reliably even for reflective sun-glasses and thin metal frames. Additionally, we identify key geometric features that can differentiate reliably the shape classes and we integrate them into a supervised learning technique for face and eye-ware shape classification. Finally, we incorporate the shape extraction and classification algorithms into a practical data-driven eye-ware recommendation system that we validate empirically with a user study.
Modelling thin-film storage channels

A straightforward method for modeling nonlinearity and data-dependent (transition-dependent) media noise in a thin-film storage channel is presented. The least-squares approach for measuring the channel linear pulse response is described, and this FIR (finite impulse response) channel model is contrasted with a nonlinear moving average modeling technique described in terms of a random-access memory used as a finite state machine (FSM). It is shown that the channel nonlinearity is largely trailing in time, and performance figures of modeling accuracy for the channel FSM are presented. The nonlinear distortion increased dramatically at higher data rates for the thin-film disk examined. In addition, the variation of the channel noise power according to the flux transition density is described. A jitter noise effect is identified. A FSM modeling technique for identifying this noise power variation as a function of the channel input data pattern is given. Finally, it is shown how to combine these two modeling techniques to create arbitrarily long, representative read signals for the thin-film disk. By using these compact channel models, one can easily test new coding or equalization techniques. >
Determination of the sequence of spaE and identification of a promoter in the subtilin (spa) operon in Bacillus subtilis

An 851-residue open reading frame (ORF) called SpaE has been discovered in the subtilin (spa) operon. Interruption of this ORF with a chloramphenicol acetyltransferase gene destroys the ability of Bacillus subtilis LH45 delta c (a derivative of B. subtilis 168) to produce subtilin, which is an antimicrobial peptide belonging to the class of ribosomally synthesized peptide antibiotics called lantibiotics. SpaE shows strong homology to NisB, which is in the nisin (nis) operon in Lactococcus lactis ATCC 11454. Despite the strong sequence homology between SpaE and NisB, the spaE and nisB genes occupy very different locations in their respective operons, indicating that they have been evolving separately for a long time. Primer extension analysis was employed to identify a promoter upstream from the spaE gene, which appears to define the 5' end of the spa operon, which contains four other ORFs (Y. J. Chung, M. T. Steen, and J. N. Hansen, J. Bacteriol. 174:1417-1422, 1992).
D‐Lactate production as a function of glucose metabolism in Saccharomyces cerevisiae

Methylglyoxal, a reactive, toxic dicarbonyl, is generated by the spontaneous degradation of glycolytic intermediates. Methylglyoxal can form covalent adducts with cellular macromolecules, potentially disrupting cellular function. We performed experiments using the model organism Saccharomyces cerevisiae, grown in media containing low, moderate and high glucose concentrations, to determine the relationship between glucose consumption and methylglyoxal metabolism. Normal growth experiments and glutathione depletion experiments showed that metabolism of methylglyoxal by log‐phase yeast cultured aerobically occurred primarily through the glyoxalase pathway. Growth in high‐glucose media resulted in increased generation of the methylglyoxal metabolite d‐lactate and overall lower efficiency of glucose utilization as measured by growth rates. Cells grown in high‐glucose media maintained higher glucose uptake flux than cells grown in moderate‐glucose or low‐glucose media. Computational modelling showed that increased glucose consumption may impair catabolism of triose phosphates as a result of an altered NAD+:NADH ratio. Copyright © 2013 John Wiley & Sons, Ltd.
Emotional labor and burnout: Comparing two perspectives of "people work"

Abstract Although it has often been presumed that jobs involving “people work” (e.g., nurses, service workers) are emotionally taxing (Maslach & Jackson, 1982), seldom is the emotional component of these jobs explicitly studied. The current study compared two perspectives of emotional labor as predictors of burnout beyond the effects of negative affectivity: job-focused emotional labor (work demands regarding emotion expression) and employee-focused emotional labor (regulation of feelings and emotional expression). Significant differences existed in the emotional demands reported by five occupational groupings. The use of surface-level emotional labor, or faking, predicted depersonalization beyond the work demands. Perceiving the demand to display positive emotions and using deep-level regulation were associated with a heightened sense of personal accomplishment, suggesting positive benefits to this aspect of work. These findings suggest new antecedents of employee burnout and clarify the emotional labor literature by comparing different conceptualizations of this concept.
Initial experience with intraoperative PTH determinations in the surgical management of 130 consecutive cases of primary hyperparathyroidism.

BACKGROUND Successful surgical management of primary hyperparathyroidism (1 degree HPT) historically has required bilateral neck exploration. The intraoperative parathyroid hormone (IO-PTH) assay allows a more limited procedure by confirming complete removal of hypersecreting tissue. METHODS Plasma samples were obtained from 130 consecutive patients both before (preincision and preexcision baselines) and at approximately 5 and 10 minutes (and additional times) after removal of abnormal parathyroid tissue. Samples were assayed for IO-PTH by a rapid, two-site immunochemiluminescent assay (ICMA) with a 7-minute incubation at 45 degrees C. RESULTS Plasma IO-PTH decreased by at least 50% in 126 of 130 cases; however, three of these cases were false positives. The four cases in which IO-PTH fell < 50% were classified as two true negatives and two false negatives. A single adenoma was removed in 125 cases, and two or three hyperplastic glands were removed in five cases. CONCLUSIONS IO-PTH predicted the postoperative outcome in 125 of 130 cases (96.2%), including two of five cases in which multiple hyperplastic glands were removed, and 1 degree HPT was successfully treated in 97.7% (127/130) of the cases. The IO-PTH procedure can provide valuable confirmation to the endocrine surgeon; however, other sources of information must also be used to ensure that all hyperplastic glands are identified.
Nerve Growth Factor Regulates Transforming Growth Factor‐β1 Gene Expression by Both Transcriptional and Posttranscriptional Mechanisms in PC12 Cells

Abstract: PC12 cells express two transforming growth factor (TGF)‐β1 transcripts, 1.7 and 2.5 kb in size. Other TGF‐βs are expressed at much lower levels. Incubation with nerve growth factor (NGF) produced a time‐ and dose‐dependent increase in content of TGF‐β1 transcripts. The level of the smaller mRNA increased little, whereas that of the 2.5‐kb transcript increased more, with the latter becoming the predominant TGF‐β1 message. NGF differentially regulated the stability of both mRNAs. The half‐life of the 2.5‐kb transcript was not altered by NGF; however, the half‐life of the 1.7‐kb mRNA was ∼6 h and increased to >30 h on incubation with NGF. In addition, induction of the 2.5‐kb TGF‐β1 mRNA by NGF required de novo protein synthesis, whereas induction of the 1.7‐kb TGF‐β1 mRNA was independent of protein synthesis. The NGF effect was independent of protein kinase C activation, which also preferentially induced the larger transcript. PC12 cells release a significant amount of TGF‐β1, and incubation with NGF further increases TGF‐β1 production. This factor is released in a latent form. These results indicate that an increase in expression and secretion of TGF‐β1 accompanies neuronal differentiation in PC12 cells. Regulation of TGF‐β1 gene expression by NGF is complex, involving both increased transcription of the TGF‐β1 gene and stabilization of the smaller TGF‐β1 transcript.
Study and characterization of intestinal yeasts of mullet (Mugil spp.) for potential probiotic use

Intestinal yeasts were isolated from 39 fish belonging to five different species of the Mugil genus. Among 42 isolates, 38 different strains belonging to 15 genera and 25 species were identified and characterized for adhesion to epitelial fish mucus, antagonistic properties against bacterial pathogens, production of enzymatic activity and biochemical properties.A great variability was found in the yeast population, and no particular prevalent yeast genera or species were detected in each single Mugil species. The genus Candida was generally well represented but also Metschnikowia, Sporidiobolus, Clavispora and Sporobolomyces were frequently found. Microbial adhesion of yeasts to the fish mucus was studied. Ten yeast strains showed a significant and specific adhering activity to mullet mucus. However, it is important to stress that some aspecific adhesion activity on glass slides was detected. Only in 3 cases the difference between glass and mucus adhesiveness was statistically significant. The inhibiting activity of yeasts was tested against various Gram-positive and Gram-negative bacterial strains, including some fish pathogens; at least 20 strains were able to antagonize the growth of the fish pathogen Aeromonas hydrophila in some culture media. The inhibitory activity was strongly influenced by the type of medium used and the sugars present in it. Most strains examined produced amylase, but not protease or lipase activity. This study, which has for the first time explored the species of yeasts present in the mullet gut, together with the adhesivity and antagonistic properties of yeast strains on mullet mucus, could be of great value for finding potential probiotic strains to be used in mullet aquaculture.
Clotrimazole as a Potent Agent for Treating the Oomycete Fish Pathogen Saprolegnia parasitica through Inhibition of Sterol 14α-Demethylase (CYP51)

ABSTRACT A candidate CYP51 gene encoding sterol 14α-demethylase from the fish oomycete pathogen Saprolegnia parasitica (SpCYP51) was identified based on conserved CYP51 residues among CYPs in the genome. It was heterologously expressed in Escherichia coli, purified, and characterized. Lanosterol, eburicol, and obtusifoliol bound to purified SpCYP51 with similar binding affinities (Ks , 3 to 5 μM). Eight pharmaceutical and six agricultural azole antifungal agents bound tightly to SpCYP51, with posaconazole displaying the highest apparent affinity (Kd , ≤3 nM) and prothioconazole-desthio the lowest (K d, ∼51 nM). The efficaciousness of azole antifungals as SpCYP51 inhibitors was confirmed by 50% inhibitory concentrations (IC50s) of 0.17 to 2.27 μM using CYP51 reconstitution assays. However, most azole antifungal agents were less effective at inhibiting S. parasitica, Saprolegnia diclina, and Saprolegnia ferax growth. Epoxiconazole, fluconazole, itraconazole, and posaconazole failed to inhibit Saprolegnia growth (MIC100, >256 μg ml−1). The remaining azoles inhibited Saprolegnia growth only at elevated concentrations (MIC100 [the lowest antifungal concentration at which growth remained completely inhibited after 72 h at 20°C], 16 to 64 μg ml−1) with the exception of clotrimazole, which was as potent as malachite green (MIC100, ∼1 μg ml−1). Sterol profiles of azole-treated Saprolegnia species confirmed that endogenous CYP51 enzymes were being inhibited with the accumulation of lanosterol in the sterol fraction. The effectiveness of clotrimazole against SpCYP51 activity (IC50, ∼1 μM) and the concentration inhibiting the growth of Saprolegnia species in vitro (MIC100, ∼1 to 2 μg ml−1) suggest that clotrimazole could be used against Saprolegnia infections, including as a preventative measure by pretreatment of fish eggs, and for freshwater-farmed fish as well as in leisure activities.
Characterization of a Grapevine R2R3-MYB Transcription Factor That Regulates the Phenylpropanoid Pathway1[W]

The ripening of grape (Vitis vinifera) berry is characterized by dramatic changes in gene expression, enzymatic activities, and metabolism that lead to the production of compounds essential for berry quality. The phenylpropanoid metabolic pathway is one of the components involved in these changes. In this study, we describe the cloning and functional characterization of VvMYB5a, a cDNA isolated from a grape L. cv Cabernet Sauvignon berry library. VvMYB5a encodes a protein belonging to a small subfamily of R2R3-MYB transcription factors. Expression studies in grapevine indicate that the VvMYB5a gene is mainly expressed during the early steps of berry development in skin, flesh, and seeds. Overexpression of VvMYB5a in tobacco (Nicotiana tabacum) affects the expression of structural genes controlling the synthesis of phenylpropanoid and impacts on the metabolism of anthocyanins, flavonols, tannins, and lignins. Overexpressing VvMYB5a induces a strong accumulation of several phenolic compounds, including keracyanin (cyanidin-3-rhamnoglucoside) and quercetin-3-rhamnoglucoside, which are the main anthocyanin and flavonol compounds in tobacco. In addition, VvMYB5a overexpression increases the biosynthesis of condensed tannins and alters lignin metabolism. These findings suggest that VvMYB5a may be involved in the control of different branches of the phenylpropanoid pathway in grapevine.
Correlation between invasive mammary carcinoma grade and size in ultrasound‐guided core needle biopsy and subsequent surgical excision

The purpose of this study was to correlate the histologic grade, mitotic rate and size of invasive mammary carcinomas (IMC) on ultrasound (US) core needle biopsy (CNB) and the follow‐up excision (FUE). The underestimation and overestimation of the grades by CNB were 11% and 8%. CNBs were more specific for grade 3 tumors. Tumors >10 mm by US examination showed greater concordance in grades. The size in the FUE was the best determinant of pT followed by US examination. The extent of IMC on CNB was larger than FUE in 8% resulting in pT upstaging in 3% of cases.
The partition system of multidrug resistance plasmid TP228 includes a novel protein that epitomizes an evolutionarily distinct subgroup of the ParA superfamily

The segregational stability of bacterial, low‐copy‐number plasmids is promoted primarily by active partition. The plasmid‐specified components of the prototypical P1 plasmid partition system consist of two proteins, ParA (44.3 kDa) and ParB (38.5 kDa), which, in conjunction with integration host factor, form a nucleoprotein complex at the plasmid partition site, parS. This complex is the probable substrate for the directed temporal and spatial intracellular movement of plasmids before cell division. The genetic organization of the partition cassette of the multidrug resistance plasmid TP228 differs markedly from that of the P1 paradigm. The TP228 system includes a novel member (ParF; 22.0 kDa) of the ParA superfamily of ATPases, of which the P1 ParA protein is the archetype. However, the ParF protein and its immediate relatives form a discrete subgroup of the ParA superfamily, which evolutionarily is more related to the MinD subgroup of cell division proteins than to ParA of P1. The TP228 and P1 partition modules differ further in that the former does not include a parB homologue, but does specify a protein (ParG; 8.6 kDa) unrelated to ParB. Homologues of the parF gene are widely disseminated on eubacterial genomes, suggesting that ParF‐mediated partition may be a common mechanism by which plasmid segregational stability is achieved.