A liquid cooled Nd:Phosphate split-disk amplifier, operating at 1053nm and one shot/min, was designed and built. Good wavefront quality is obtained, in agreement with multi-physics modeling and with ...performance needs on high power laser systems.
PETAL is an additional PW beamline to the LMJ. The kJ shots in the amplifier section, the compressor alignment and the 1.15 PW @ 850 J operations are detailed. Damage issues encountered are also ...addressed.
Dédié à l’étude des plasmas denses et chauds au sein du programme de Simulation du CEA DAM, le laser Mégajoule est actuellement l’un des lasers les plus énergétiques du monde. Après la mise en route ...d’une première chaîne laser en 2014, il comprend aujourd’hui 11 chaines lasers (soit 88 faisceaux lasers) délivrant quotidiennement jusqu’à 330 kJ d’énergie sur cible à la longueur d’onde de 351 nm. Nous décrivons le système laser LMJ, les performances atteintes dans sa configuration actuelle, ainsi que les campagnes lasers conduites pour amener l’installation à une énergie de 1.3 MJ, une fois les 22 chaines lasers montées et qualifiées.
Bien qu’assez ancien, le débat sur la restitution des patrimoines acquis de manière illégitime durant la colonisation a connu une réactualisation certaine depuis 2017. Dans le sillage de ce ...renouveau, une redéfinition du modèle de gestion des collections publiques semble apparaître entre amendement au principe d’inaliénabilité des collections, études de provenance et émergence d’un patrimoine commun et circulant. Ayant pourtant vocation à exercer un magistère sur l’administration des collections, les conservateurs du patrimoine semblent demeurer extérieurs aux discussions dans la mesure où ceux-ci ont été déplacés des musées vers l’arène parlementaire dans un contexte du juridicisation de la question. Face à une telle éviction, comment les conservateurs réagissent-ils ? Connaissent-ils les termes du débat et souhaitent-ils davantage y être associés ? Cet article a pour objectif de présenter quelques éléments de réponse à ces interrogations en revenant sur les résultats d’une enquête par questionnaire au sujet de l’appréhension du sujet des restitutions par le corps des conservateurs.
Background:
Few data are available on the effects of a psychiatric label on medical residents’ attitudes towards an individual.
Aims:
To investigate the effect of a psychiatric label on the attitudes ...of medical residents towards an individual.
Methods:
Medical residents were randomly assigned to one of two vignettes describing the same apparently healthy person, differing only in the presence of a psychiatric label for one of them. Participants (N = 322) reported their attitudes towards the described individual and their willingness to treat this person.
Results:
Residents allocated to the psychiatric-diagnostic label group reported being less at ease with becoming the individual’s nextdoor neighbour, working in the same place, sharing a house, having him look after their children, having a member of their family date him, having their finances run by the individual, less willing to become friends with the described individual and more uneasy having to examine him the next time he visits the emergency room.
Conclusion:
Implementing effective programmes to combat stigma in the curriculum of medical residents appears to be needed.
We present the experimental demonstration of a subaperture compression scheme achieved in the PETAL (PETawatt Aquitaine Laser) facility. We evidence that by dividing the beam into small subapertures ...fitting the available grating size, the sub-beam can be individually compressed below 1 ps, synchronized below 50 fs and then coherently added thanks to a segmented mirror.
T2D4, a T-cell hybrid, spontaneously secretes suppressive immunoglobulin factor(s); when incubated with purified monoclonal mouse immunoglobulins, this hybrid produces high levels of ...immunoglobulin-binding factors specific for the subclass of the inducing immunoglobulin. Thus, we were able to induce the production of IgG1- or IgG2-specific inhibitory factors by the same T2D4 T-cell hybrid. These subclass-specific suppressive factors bind selectively to the IgG1 or IgG2 subclasses and inhibit specifically the secretion of antibodies of the corresponding subclass. Our results favor a model of negative regulation of isotype expression in which a given isotype triggers suppressor mechanism(s) specifically inhibiting its production.
Les procédés de fabrication de composants optiques ont un impact sur leur capacité à soutenir de forts flux laser. Nous présentons les travaux menés sur les procédés de polissage et l'optique ...diffractive pour en comprendre et améliorer les performances.
Poly A RNA has been isolated from a murine T cell hybridoma ( T2D4 ) that spontaneously secretes suppressive immunoglobulin G-binding factor ( IgGBF ). Translation products, obtained from a rabbit ...reticulocyte lysate translation system and after injection into Xenopus laevis oocytes, contain material with the biologic activity, the affinity, and the m.w. of murine IgGBF ; it suppresses secondary in vitro IgG antibody production in a dose-dependent fashion. The suppressive factor binds to IgG but not to IgM immunoadsorbents and, after mild NaDodSO4 treatment, dissociates in NaDodSO4 polyacrylamide gels into two peaks at 78 and 40 kD. Translation products from two non- IgGBF -secreting cell lines (BW-5147, a T lymphoma line, and A9, a fibroblast cell line) fail to exert any suppressive activity. On sucrose gradients, the RNA responsible for the biologic activity was found in one major peak located at 11S. IgGBF synthesized in a cellfree translation system by using poly A RNA and sucrose gradient fractions was also characterized by immunoprecipitation with Fc fragments of 35Smethionine-labeled proteins. On NaDodSO4 polyacrylamide gels, it migrates in one peak located at 37 kD. We conclude that IgGBF is coded for by 11S poly A RNA and that no post-translational modifications (other than proteolytic cleavage) are necessary to obtain a biologically active factor with Ig-binding properties.
Abstract
A subpopulation of activated murine T cells (25%) were found to bear Fc receptors for mouse, rabbit, and human IgG. Studies, by rosette inhibition and indirect immunofluorescence, of their ...specificity for human IgG subclasses have shown that these receptors bound nonaggregated IgG1, IgG2, and IgG3 in a comparable fashion, but did not bind IgG4. The binding site has been localized exclusively to the Fc region and the binding capacity of this fragment was not affected by mild reduction. Binding of the Fc fragment of IgG4 could not be demonstrated. Using isolated Cγ2 and Cγ3 (pFc′) domains from IgG1 and a Cγ3-derived fragment (Fc′), a major binding site was localized to the Cγ3 domain between residues Gln342 and His433. A 10-fold molar excess of Cγ3 dimer over native Fc was, however, required to show comparable activity. The monomeric Cγ2 domain was 10-fold less active than the Cγ3 fragment. Human urine β2-microglobulin was not cytophilic. These data are discussed and it is suggested that the Cγ2 and Cγ3 domains may contribute to the formation of a cooperative binding site through quaternary interdomain interactions.
By redistribution experiments, it was demonstrated that the three human IgG subclasses shown to be cytophilic share common or linked receptors, which were not associated with the H-2 alloantigens.
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