331 research outputs found
Runaway electrons from a ‘beam-bulk’ model of streamer: application to TGFs
International audienc
Propylthiocyclopentadiene: A new synthetic route to complexes of iron and group 4 transition metals. Molecular structure of (C5H4SCH2CH2CH3)(2)ZrCl2
The use of the propylthio-substituted cyclopentadienylsodium salt leads to 1,1'-bis(propylthio) ferrocene and dichlorobis(propylthiocyclopentadienyl)zirconium, titanium or hafnium(IV). The structure of (C5H4SCH2CH2CH3)(2)ZrCl2 has been established by X-ray analysis (orthorhombic, Pbcn, a = 11.943(1) Angstrom, b = 6.883(2) Angstrom, c = 22.412(2) Angstrom, V = 1842.4(2) Angstrom(3), Z = 4, R(F) = 0.027). The complexes have been characterized by H-1 and C-13 NMR and electrochemical studies. The physico chemical properties of 1,1'-bis(propylthio) ferrocene are discussed by a molecular approach at the extended Huckel level
Diffusion géométrique pour le masquage d'erreurs de quantification et de transmission sur des images JPEG couleur
Nous proposons ici une méthode de masquage d'erreurs de transmission basée contenue. Contrairement aux schémas classiques de correction d'erreurs de type FEQ/ARQ, notre méthode ne nécessite pas l'ajout de données de contrôle, et exploite directement la redondance spatiale de l'image source. Elle consiste en effet à interpoler les zones valides de l'image reçue dans les zones corrompues, à l'aide d'un processus de diffusion sous contraintes géométriques couplé à une approche multi-résolution. Outre les erreurs de transmission, ce modèle de diffusion nous permet de masquer également les erreurs de quantification (artefacts de compression)
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Randomized Controlled Trial of Parent Therapeutic Education on Antibiotics to Improve Parent Satisfaction and Attitudes in a Pediatric Emergency Department
Objective: To evaluate therapeutic education delivered in a pediatric emergency department to improve parents’ satisfaction and attitudes about judicious antibiotic use. Methods: In an emergency department of a tertiary pediatric hospital, children aged 1 month to 6 years and discharged with an oral antibiotic prescription for an acute respiratory or urinary tract infection were randomized to a patient therapeutic education on antibiotic use (intervention group) or fever control (control group) delivered to the parents (in the presence of the children) by a pharmacist trained in therapeutic education. Education consisted in a 30-minute face-to-face session with four components: educational diagnosis, educational contract, education, and evaluation. The main outcome measure was parent satisfaction about information on antibiotics received at the hospital, as assessed by a telephone interview on day 14. The secondary outcome was attitudes about antibiotic use evaluated on day 14 and at month 6. Results: Of the 300 randomized children, 150 per arm, 259 were evaluated on day 14. Parent satisfaction with information on antibiotics was higher in the intervention group (125/129, 96.9%, versus 108/130, 83.0%; P=0.002, exact Fisher test). Intervention Group parents had higher proportions of correct answers on day 14 to questions on attitudes about judicious antibiotic use than did control-group parents (P=0.017, Mann-Whitney U test). Conclusion: Therapeutic education delivered by a clinical pharmacist in the pediatric emergency department holds promise for improving the use of antibiotics prescribed to pediatric outpatients. Trial Registration ClinicalTrials.gov NCT00948779 http://clinicaltrials.gov/show/NCT0094877
The nonstructural NS1 protein of influenza viruses modulates TP53 splicing through host factor CPSF4
International audienceInfluenza A viruses (IAV) are known to modulate and "hijack" several cellular host mechanisms, including gene splicing and RNA maturation machineries. These modulations alter host cellular responses and enable an optimal expression of viral products throughout infection. The interplay between the host protein p53 and IAV, in particular through the viral nonstructural protein NS1, has been shown to be supportive for IAV replication. However, it remains unknown whether alternatively spliced isoforms of p53, known to modulate p53 transcriptional activity, are affected by IAV infection and contribute to IAV replication. Using a TP53 minigene, which mimics intron 9 alternative splicing, we have shown here that the NS1 protein of IAV changes the expression pattern of p53 isoforms. Our results demonstrate that CPSF4 (cellular protein cleavage and polyadenylation specificity factor 4) independently and the interaction between NS1 and CPSF4 modulate the alternative splicing of TP53 transcripts, which may result in the differential activation of p53-responsive genes. Finally, we report that CPSF4 and most likely beta and gamma spliced p53 isoforms affect both viral replication and IAV-associated type I interferon secretion. All together, our data show that cellular p53 and CPSF4 factors, both interacting with viral NS1, have a crucial role during IAV replication that allows IAV to interact with and alter the expression of alternatively spliced p53 isoforms in order to regulate the cellular innate response, especially via type I interferon secretion, and perform efficient viral replication
Il y a une vie après MARC
Interventions à la journée d\u27étude organisée en hommage à Pierre-Yves-Duchemin : Bibliothécaires et normalisation documentaire : de l\u27implication individuelle au travail dans le cadre d\u27une association ou d\u27une institution (F. Bourdon, BnF) ; L\u27évolution des règles de catalogage : ISBD consolidé et RDA (F. Leresche, BnF) ; L\u27information bibliographique enrichie et la concertation entre bibliothécaires et fournisseurs de systèmes et de données (D. Lahary, BDP du Val d\u27Oise) ; Le Département des Cartes et Plans de la Bibliothèque nationale de France, ses collections et leur traitement. (O. Loiseaux, BnF) ; Le projet BN Richelieu avec notamment l’informatisation et la base PIXML (M.-Cl. Thompson, BnF) ; De MARC à XML : les nouveaux formats (T. Clavel, Enssib) ; EAD, un standard d\u27encodage pour les descriptions de manuscrits et d\u27archives (C. Sibille, DAF) ; TEI : Text Encoding Initiative (J.-L. Benoit, ATILF)
Heat shock factor-1 modulates p53 activity in the transcriptional response to DNA damage
Here we define an important role for heat shock factor 1 (HSF1) in the cellular response to genotoxic agents. We demonstrate for the first time that HSF1 can complex with nuclear p53 and that both proteins are co-operatively recruited to p53-responsive genes such as p21. Analysis of natural and synthetic cis elements demonstrates that HSF1 can enhance p53-mediated transcription, whilst depletion of HSF1 reduces the expression of p53-responsive transcripts. We find that HSF1 is required for optimal p21 expression and p53-mediated cell-cycle arrest in response to genotoxins while loss of HSF1 attenuates apoptosis in response to these agents. To explain these novel properties of HSF1 we show that HSF1 can complex with DNA damage kinases ATR and Chk1 to effect p53 phosphorylation in response to DNA damage. Our data reveal HSF1 as a key transcriptional regulator in response to genotoxic compounds widely used in the clinical setting, and suggest that HSF1 will contribute to the efficacy of these agents
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