129 research outputs found

    Anharmonicity and asymmetry of Landau levels for a two-dimensional electron gas

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    We calculate the density of states of a two dimensional electron gas located at the interface of a GaAlAs/GaAs heterojunction. The disorder potential which is generally created by a single doping layer behind a spacer, is here enhanced by the presence of a second delta doped layer of scatterers which can be repulsive or attractive impurities. We have calculated the density of states by means of the Klauder's approximation, in the presence of a magnetic field of arbitrary strength. At low field either band tails or impurity bands are observed for attractive potentials, depending on the impurity concentration. At higher field, impurity bands are observed for both repulsive and attractive potentials. We discuss the effect of such an asymmetrical density of states on the transport properties in the quantum Hall effect regime.Comment: 22 pages, 12 figures. submitted to Phys. Rev.

    In silico-in vitro screening of protein-protein interactions: towards the next generation of therapeutics.

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    International audienceProtein-protein interactions (PPIs) have a pivotal role in many biological processes suggesting that targeting macromolecular complexes will open new avenues for the design of the next generation of therapeutics. A wide range of "in silico methods" can be used to facilitate the design of protein-protein modulators. Among these methods, virtual ligand screening, protein-protein docking, structural predictions and druggable pocket predictions have become established techniques for hit discovery and optimization. In this review, we first summarize some key data about protein-protein interfaces and introduce some recently reported computer methods pertaining to the field. URLs for several recent free packages or servers are also provided. Then, we discuss four studies aiming at developing PPI modulators through the combination of in silico and in vitro screening experiments

    EVI1 overexpression in t(3;17) positive myeloid malignancies results from juxtaposition of EVI1 to the MSI2 locus at 17q22

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    Chromosomal translocations involving the EVI1 locus are a recurrent finding in myeloid leukemia and are associated with poor prognosis. In this study, we performed a detailed molecular characterization of the recurrent translocation t(3;17)(q26;q22) in 13 hematologic malignancies. The EVI1 gene locus was rearranged in all 13 patients and was associated with EVI1 overexpression. In 9 out of 13 patients, the 17q breakpoints clustered in a 250 kb region on band 17q22 encompassing the MSI2 (musashi homologue 2) gene. Expression analyses failed to demonstrate ectopic MSI2 expression or the presence of an MSI2/EVI1 fusion gene. In conclusion, we show for the first time that the t(3;17) is indeed a recurrent chromosomal aberration in myeloid malignancies. In keeping with findings in other recurrent 3q26 rearrangements, overexpression of the EVI1 gene appears to be the major contributor to leukemogenesis in patients with a t(3; 17)

    Evaluation de la stratégie de lutte contre le cancer en Suisse, Phase 2, 2002 : document de synthÚse

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    [Table des matiĂšres] 1. Introduction. 2. MĂ©thode. 3. Conclusions et recommandations gĂ©nĂ©rales. 3.1. StratĂ©gie. 3.2. Conclusions et recommandations concernant la stratĂ©gie, les structures et le fonctionnement, la collaboration avec l'extĂ©rieur. 3.3. Les 4 programmes nationaux. 3.4. Conclusions et recommandations pour les 4 programmes nationaux. 3.5. Bilan de l'expĂ©rience de la mise en place du dĂ©pistage du sein. 3.6. Conclusions et recommandations pour la mise en place du dĂ©pistage du sein. 3.7. Les donnĂ©es Ă  disposition pour le suivi et l'Ă©valuation de la stratĂ©gie nationale de lutte contre le cancer. 3.8. Conclusions et recommandations pour le suivi et l'Ă©valuation de la stratĂ©gie nationale de lutte contre le cancer. 4. Annexes: RĂ©sumĂ©s des Ă©tudes 1 Ă  7. Etude 1: Suivi du dĂ©veloppement de la stratĂ©gie nationale. Studie 2: Prozessevaluation und Prozessdokumentation. Studie 3: Mammographie-Screening in der Schweiz : eine retrospektive Analyse zur Umsetzung. Studie 4: SekundĂ€re Analyse der verfĂŒgbaren Indikatoren zur Messung der Ergebnisse des nationalen KrebsbekĂ€mpfungsprogrammes. Etude 5: Quel ancrage local des actions de la Ligue suisse contre le cancer ? : l'exemple de la prĂ©vention du mĂ©lanome. Studie 6: Begleitevaluation der Pilotphase des Aktionsmonats Brustkrebs. Etude 7: Accompagnement psychosocial des personnes ayant un diagnostic de cancer : Ă©tude de deux cantons

    TMT DMs final design and advanced prototyping results at Cilas

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    In order to prepare for the construction phase of the two Deformable Mirrors (DMs), which will be used in the Thirty Meter Telescope (TMT) first light Adaptive Optics (AO) system, Cilas has advanced the design of these two large size piezo DMs and has manufactured and tested a scaled demonstration prototype. The work done allowed significant reduction of the risks related to the demanding specifications of the TMT DMs; the main issues were: (i) Large pupil (up to 370 mm) and high order (up to 74x74); (ii) Relatively low operational temperature (DMs working at -30°C); (iii) New piezo material. It is important to develop such a prototype to take into account these three specifications all together (dimension, low temperature and new piezo material). The new prototype is a 6x60 actuators and has the same characteristics as the future TMT DMs. In this paper, we give the conclusions of the work through the presentation of the following items: (i) Design and finite element analysis of the two DMs and prototype; (ii) Test results obtained with the prototype with validation of the finite element analysis and compliance with the TMT AO specifications; (iii) Special focus on thermal behavior, actuator reliability and shape at rest stability

    Imidazole propionate is increased in diabetes and associated with dietary patterns and altered microbial ecology

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    Microbiota-host-diet interactions contribute to the development of metabolic diseases. Imidazole propionate is a novel microbially produced metabolite from histidine, which impairs glucose metabolism. Here, we show that subjects with prediabetes and diabetes in the MetaCardis cohort from three European countries have elevated serum imidazole propionate levels. Furthermore, imidazole propionate levels were increased in subjects with low bacterial gene richness and Bacteroides 2 enterotype, which have previously been associated with obesity. The Bacteroides 2 enterotype was also associated with increased abundance of the genes involved in imidazole propionate biosynthesis from dietary histidine. Since patients and controls did not differ in their histidine dietary intake, the elevated levels of imidazole propionate in type 2 diabetes likely reflects altered microbial metabolism of histidine, rather than histidine intake per se. Thus the microbiota may contribute to type 2 diabetes by generating imidazole propionate that can modulate host inflammation and metabolism

    Autoantibodies against type I IFNs in patients with critical influenza pneumonia

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    In an international cohort of 279 patients with hypoxemic influenza pneumonia, we identified 13 patients (4.6%) with autoantibodies neutralizing IFN-alpha and/or -omega, which were previously reported to underlie 15% cases of life-threatening COVID-19 pneumonia and one third of severe adverse reactions to live-attenuated yellow fever vaccine. Autoantibodies neutralizing type I interferons (IFNs) can underlie critical COVID-19 pneumonia and yellow fever vaccine disease. We report here on 13 patients harboring autoantibodies neutralizing IFN-alpha 2 alone (five patients) or with IFN-omega (eight patients) from a cohort of 279 patients (4.7%) aged 6-73 yr with critical influenza pneumonia. Nine and four patients had antibodies neutralizing high and low concentrations, respectively, of IFN-alpha 2, and six and two patients had antibodies neutralizing high and low concentrations, respectively, of IFN-omega. The patients' autoantibodies increased influenza A virus replication in both A549 cells and reconstituted human airway epithelia. The prevalence of these antibodies was significantly higher than that in the general population for patients 70 yr of age (3.1 vs. 4.4%, P = 0.68). The risk of critical influenza was highest in patients with antibodies neutralizing high concentrations of both IFN-alpha 2 and IFN-omega (OR = 11.7, P = 1.3 x 10(-5)), especially those <70 yr old (OR = 139.9, P = 3.1 x 10(-10)). We also identified 10 patients in additional influenza patient cohorts. Autoantibodies neutralizing type I IFNs account for similar to 5% of cases of life-threatening influenza pneumonia in patients <70 yr old

    Vaccine breakthrough hypoxemic COVID-19 pneumonia in patients with auto-Abs neutralizing type I IFNs

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    Life-threatening `breakthrough' cases of critical COVID-19 are attributed to poor or waning antibody response to the SARS- CoV-2 vaccine in individuals already at risk. Pre-existing autoantibodies (auto-Abs) neutralizing type I IFNs underlie at least 15% of critical COVID-19 pneumonia cases in unvaccinated individuals; however, their contribution to hypoxemic breakthrough cases in vaccinated people remains unknown. Here, we studied a cohort of 48 individuals ( age 20-86 years) who received 2 doses of an mRNA vaccine and developed a breakthrough infection with hypoxemic COVID-19 pneumonia 2 weeks to 4 months later. Antibody levels to the vaccine, neutralization of the virus, and auto- Abs to type I IFNs were measured in the plasma. Forty-two individuals had no known deficiency of B cell immunity and a normal antibody response to the vaccine. Among them, ten (24%) had auto-Abs neutralizing type I IFNs (aged 43-86 years). Eight of these ten patients had auto-Abs neutralizing both IFN-a2 and IFN-., while two neutralized IFN-omega only. No patient neutralized IFN-ss. Seven neutralized 10 ng/mL of type I IFNs, and three 100 pg/mL only. Seven patients neutralized SARS-CoV-2 D614G and the Delta variant (B.1.617.2) efficiently, while one patient neutralized Delta slightly less efficiently. Two of the three patients neutralizing only 100 pg/mL of type I IFNs neutralized both D61G and Delta less efficiently. Despite two mRNA vaccine inoculations and the presence of circulating antibodies capable of neutralizing SARS-CoV-2, auto-Abs neutralizing type I IFNs may underlie a significant proportion of hypoxemic COVID-19 pneumonia cases, highlighting the importance of this particularly vulnerable population

    Jean-Pierre Royer, La Société judiciaire depuis le XVÚme siÚcle, 1979 ; Christian Hennion, Yves Lemoine, «Juges et procureurs, histoire d'une perversion» «Recherches », n° 40, mars 1980 ; Monique Pauti, Les Magistrats de l'ordre judiciaire, 1979

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    Bastard Benoit. Jean-Pierre Royer, La SociĂ©tĂ© judiciaire depuis le XVĂšme siĂšcle, 1979 ; Christian Hennion, Yves Lemoine, «Juges et procureurs, histoire d'une perversion» «Recherches », n° 40, mars 1980 ; Monique Pauti, Les Magistrats de l'ordre judiciaire, 1979. In: Sociologie du travail, 23ᔉ annĂ©e n°3, Juillet-septembre 1981. pp. 352-355

    Quelle contribution des avocats à la justice sociale ?

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    S’il ne fait pas de doute que les avocats contribuent Ă  l’accĂšs Ă  la justice, contribuent-ils Ă©galement Ă  la justice sociale ? La profession d’avocat a connu des changements considĂ©rables dans les derniĂšres dĂ©cennies, mais les clivages qui la traversent sont restĂ©s intacts. La lutte contre les discriminations revient pour l’essentiel aux avocats judiciaires, qui reprĂ©sentent, au civil et au pĂ©nal les justiciables dĂ©munis ou en difficultĂ©. D’autres segments du barreau se trouvent peu concernĂ©s par l’action en justice et concentrent davantage de ressources. Pourtant, la profession prĂ©sente un front uni et maintient sa position malgrĂ© ces clivages, ce qui donne tout son intĂ©rĂȘt Ă  l’étude de ses instances dirigeantes. En prenant appui sur une recherche portant sur le rĂŽle que joue l’Ordre des avocats, notamment en matiĂšre de discipline et dans le dĂ©veloppement du numĂ©rique, cette confĂ©rence questionne l’impact des transformations rĂ©centes sur la vie judiciaire et la maniĂšre dont les avocats participent Ă  l’exercice de la justice
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