We report on a search for elementary particles with charges much smaller than the electron charge using a data sample of proton-proton collisions provided by the CERN Large Hadron Collider in 2018, ...corresponding to an integrated luminosity of 37.5 fb−1 at a center-of-mass energy of 13 TeV. A prototype scintillator-based detector is deployed to conduct the first search at a hadron collider sensitive to particles with charges ≤ 0.1 e . The existence of new particles with masses between 20 and 4700 MeV is excluded at 95% confidence level for charges between 0.006 e and 0.3 e , depending on their mass. New sensitivity is achieved for masses larger than 700 MeV.
Phys. Rev. D 102, 032002 (2020) We report on a search for elementary particles with charges much smaller than
the electron charge using a data sample of proton-proton collisions provided by
the CERN ...Large Hadron Collider in 2018, corresponding to an integrated
luminosity of 37.5 fb$^{-1}$ at a center-of-mass energy of 13 TeV. A prototype
scintillator-based detector is deployed to conduct the first search at a hadron
collider sensitive to particles with charges ${\leq}0.1e$. The existence of new
particles with masses between 20 and 4700 MeV is excluded at 95% confidence
level for charges between $0.006e$ and $0.3e$, depending on their mass. New
sensitivity is achieved for masses larger than $700$ MeV.
We report on a search for elementary particles with charges much smaller than the electron charge using a data sample of proton-proton collisions provided by the CERN Large Hadron Collider in 2018, ...corresponding to an integrated luminosity of 37.5 fb\(^{-1}\) at a center-of-mass energy of 13 TeV. A prototype scintillator-based detector is deployed to conduct the first search at a hadron collider sensitive to particles with charges \({\leq}0.1e\). The existence of new particles with masses between 20 and 4700 MeV is excluded at 95% confidence level for charges between \(0.006e\) and \(0.3e\), depending on their mass. New sensitivity is achieved for masses larger than \(700\) MeV.
Summary
The aim of our study was to evaluate the performance of different durations of active pre‐operative skin‐surface warming (pre‐warming) to prevent peri‐operative hypothermia and postoperative ...shivering. We randomly assigned 200 patients, scheduled for surgery of 30–90 min under general anaesthesia, to receive passive insulation or forced‐air skin surface warming for 10, 20 or 30 min. Body temperature was measured at the tympanic membrane. Shivering was graded by visual inspection. There were significant differences in changes of core temperature between the non‐pre‐warmed group and all the pre‐warmed groups (p < 0.00001), but none between the three pre‐warmed groups (p = 0.54). Without pre‐warming, 38/55 (69%) patients became hypothermic (< 36 °C) at the end of anaesthesia, whereas only 7/52 (13%), 3/43 (7%) and 3/50 (6%) patients following 10, 20 or 30 min pre‐warming, respectively, became hypothermic (p < 0.001 vs no pre‐warming). Shivering was observed in 10 patients without, and in three, three and one patients with pre‐warming in the respective groups (p = 0.02). Pre‐warming of patients for only 10 or 20 min before general anaesthesia mostly prevents hypothermia and reduces shivering.
Our understanding of the conformational and electrostatic determinants that underlie targeting of human leukocyte antigens (HLA) by anti-HLA alloantibodies is principally based upon in silico ...modelling. Here we provide a biochemical/biophysical and functional characterization of a human monoclonal alloantibody specific for a common HLA type, HLA-A*11:01. We present a 2.4 Å resolution map of the binding interface of this antibody on HLA-A*11:01 and compare the structural determinants with those utilized by T-cell receptor (TCR), killer-cell immunoglobulin-like receptor (KIR) and CD8 on the same molecule. These data provide a mechanistic insight into the paratope-epitope relationship between an alloantibody and its target HLA molecule in a biological context where other immune receptors are concomitantly engaged. This has important implications for our interpretation of serologic binding patterns of anti-HLA antibodies in sensitized individuals and thus, for the biology of human alloresponses.
Illegal U-turns on freeways and toll roads are risky maneuvers that sometimes result in the turning vehicles causing various types of collisions or disturbances to approaching traffic. These illegal ...U-turn maneuvers can occur at traversable grass medians and emergency crossovers. Limited literature was found regarding the impact of illegal U-turns on these facilities. Therefore, to understand the roadway and median characteristics that could influence drivers’ propensity to commit illegal U-turns, a sequential modeling methodology was adopted. This methodology combined a Poisson regression model with a Least Absolute Shrinkage and Selection Operator (LASSO) regression procedure to predict the cited violations at traversable median segments. Additionally, a logistic regression model was developed to predict the probability of a cited violation at official use only emergency crossovers. These models included illegal U-turn citations and crashes for the Orlando and Miami metropolitan areas in Florida from 2011 to 2016. The findings indicated that the average distance between access points, median width, speed limit, segment length, and distance to nearest segment were significant in predicting cited violations at traversable medians. Furthermore, the distance to the nearest interchange, distance to the nearest adjacent crossover, and median width were significant in predicting the probability of a cited violation occurring at an emergency crossover. This study helps agencies to predict the locations of illegal U-turn violations and to prioritize roadways for possible treatment to minimize the potential risk of head-on or other collisions due to illegal U-turn events.
The design of future multi-standard systems is very challenging. Flexible architectures exploiting processing commonalities of the different set of standards cohabiting in the device offer promising ...solutions. In this paper, graph theory aspects are introduced with the stress on the notion of directed hypergraphs which will help in showing how the graph structure of the multi-standard system can be viewed as a theoretical directed hypergraph. This graph description provides all the alternatives capable of implementing the design. However, a cost function needs to be defined to calculate the cost of each possible option chosen. Thus, we explain the sound concept of the computation process of a cost function introduced in previous papers, before transforming it into a formal expression with the aid of various definitions and notations of directed hypergraphs.
Agrobacterium tumefaciens est une bactérie du sol responsable de la galle du collet chez les plantes lorsqu'elle possède le plasmide Ti (Tumor inducing) dit de virulence (pTi). La bactérie transfère ...un morceau d’ADN du pTi dans le génome de la plante qui code d'une part la production d’hormones de plantes, à l’origine de la formation de tumeurs colonisées par les bactéries et d'autre part la production de petites molécules (opines) qui servent de nutriment à A. tumefaciens. L'opine, agrocinopine A induit la production de signaux quorum sensing à l’origine de la dissémination du plasmide de virulence vers des bactéries non pathogènes. Agrobacterium radiobacter K84, une bactérie non pathogène, produit de l’agrocine 84, un antibiotique qui tue A. tumefaciens.L’import et le catabolisme de l’agrocinopine A sont réalisés par l’opéron acc présent sur le pTi. La protéine périplasmique (PBP) AccA associée à un transporteur ABC importe l’opine dans le cytoplasme qui est ensuite dégradée par AccF et AccG. AccR régule l’expression de l’opéron acc et celle du facteur de transcription TraR, central dans la signalisation quorum sensing. AccA importe l’agrocine 84 qui est activée par AccF. Mon travail de doctorat a permis par des études structure-fonction de caractériser la spécificité d'AccA et d’AccF et d’initier l’étude du facteur de transcription AccR. L’étude structurale de la PBP en complexe avec l’agrocinopine A, l’agrocine 84 et des dérivés de ces molécules a révélé que seul le motif pyranose-2-phosphate commun aux 2 molécules était reconnu par AccA. Cela a été confirmé par microcalorimétrie et autofluorescence. Le motif pyranose-2-phosphate permettrait donc l’entrée de toute molécule qui le possède à une extrémité. La structure de l’enzyme AccF a montré que là encore seul le groupement pyranose-2-phosphate est reconnu. A partir de la structure obtenue et de modélisation du substrat dans le site actif, un mécanisme enzymatique original pour l’hydrolyse de la liaison phosphodiester est proposé. Les mesures d’affinité par microcalorimétrie montrent que seuls l’arabinose-2-phosphate et le glucose-2-phosphate sont capables de fixer AccR. Des expériences in cellulo ont confirmé qu'ils régulent bien l'expression du QS.Mes travaux apportent un éclairage nouveau sur l’import et l'utilisation de l’agrocinopine chez A. tumefaciens. La spécificité de reconnaissance de la PBP pour une partie de la molécule importée est observée chez d’autres PBP, et ouvre la voie à la conception de molécules antibiotiques qui, à l’image de l’agrocine 84, utilisent une stratégie de type « cheval de Troie ».
Agrobacterium tumefaciens is a soil bacterium responsible of the crown gall in plants when it possesses the Tumor inducing plasmid (pTi) which is also the virulence plasmid. The bacterium transfers a piece of DNA from the pTi into the plant genome. The transferred DNA codes for plant hormone synthesis, leading to the formation of tumors which are colonized by bacteria, on one hand, and on the other hand, for the synthesis of small molecules (opines) that are used as nutrients by A. tumefaciens. The opine agrocinopine A induces the production of quorum sensing signals responsible for the spread of the virulence plasmid from pathogenic to nonpathogenic bacterium. Agrobacterium radiobacter K84, a nonpathogenic bacterium, produces the agrocin 84, an antibiotic that kills A. tumefaciens.Import and catabolism of agrocinopine A are operated by acc operon, present on the pTi. The periplasmic binding protein AccA (PBP AccA) associated with the ABC transporter imports the opine into the periplasm where it is degraded by AccF and AccG. AccR regulates the expression of the acc operon and that of the transcription factor TraR, central in quorum sensing signaling. AccA also imports agrocin 84, which is activated by AccF. My PhD work focused on AccA and AccF specificity through structure-function studies and I initiated the study of the transcription factor AccR. The structural study of AccA in complex with agrocinopine A, agrocin 84 and derivatives from these molecules revealed that only the pyranose-2-phosphate motif, common in these two molecules, was recognized. Microcalorimetry and autofluorescence measurements confirmed this conclusion. The pyranose-2-phosphate motif would allow any compound possessing this motif at one end to be transported. The structure of the enzyme AccF showed that again only the pyranose-2-phosphate group is recognized. From the structure and molecular modelling of the substrate in the active site, an original mechanism of the phosphodiester bond cleavage is proposed. Microcalorimetry affinity measures showed that only the arabinose-2-phosphate and glucose-2-phosphate are capable of interacting with AccR. In cellulo experiments confirm that both compounds regulate the expression of quorum sensing.My work sheds light on import and use of agrocinopine in A. tumefaciens. Recognition specificity of the PBP AccA for a part of the imported molecule is observed in other PBPs and opens new ways for rational design of antibiotic compounds that, similarly to agrocin 84, would use the “Trojan horse” strategy.
Etude portant sur la retenue du barrage Al Massira qui a fait l' objet d' un programme de recherche ayant pour objectif la modelisation de la qualite des eaux de cette retenue en vue d' etudier le ...probleme d' eutrophisation.
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