68 research outputs found
Connected Lie groups and property RD
For a locally compact group, property RD gives a control on the convolution
norm of any compactly supported measure in terms of the -norm of its
density and the diameter of its support. We give a complete classification of
those Lie groups with property RD.Comment: 29 page
RĂ©cupĂ©ration du liant bitumineux provenant dâextraction Mise en application et adaptation de la nouvelle norme europĂ©enne vis Ă vis des expĂ©riences suisses
LâapprĂ©ciation du taux de vieillissement des enrobĂ©s par la caractĂ©risation du liant rĂ©cupĂ©rĂ© est de plus en plus utilisĂ© en technique routiĂšre. Les mandats de recherches prĂ©cĂ©dents, (FA 7/75 [1], FA 7/77 [2] et FA 16/88 [3]) ont permis de dĂ©finir, en Suisse, une mĂ©thodologie qui donne satisfaction autant pour ce qui concerne la prĂ©cision des rĂ©sultats obtenus (rĂ©pĂ©tabilitĂ© et reproductibilitĂ©) que la simplicitĂ© et la rapiditĂ© de rĂ©alisation. Ces Ă©tudes ont permis dâĂ©laborer la norme SN 671 860 "Liants bitumineux, prescriptions dâessai â RĂ©cupĂ©ration du liant rĂ©siduel provenant dâextractions" [4]. La prĂ©-norme europĂ©enne 12697-3 [5] de mars 1998 proposait lâutilisation dâun solvant unique, le dichloromĂ©thane (chlorure de mĂ©thylĂšne) avec des conditions dâessais plus larges que la norme suisse (dĂ©pression, tempĂ©rature, masse de liant). Lâintervention de plusieurs partenaires europĂ©ens dont la Suisse a permis dâinclure lâutilisation dâautres solvants dans la version dĂ©finitive EN 12697-3 dâoctobre 2000 [6]. Ce travail de recherche dont le but est de faciliter la mise en application de la norme europĂ©enne a permis de tester dâune part la mĂ©thode issue de la norme EN avec des conditions basĂ©es sur lâutilisation de dichloromĂ©thane et dâautre part la mĂ©thode SN qui propose lâutilisation de toluĂšne. Ce travail a aussi mis en Ă©vidence lâimprĂ©cision de la norme europĂ©enne. Les rĂ©sultats obtenus lors des essais dâinvestigations ont mis en Ă©vidence la problĂ©matique dâutilisation du toluĂšne avec les conditions dĂ©finies dans la norme EN qui sont spĂ©cifiques au dichloromĂ©thane. Ces rĂ©sultats montrent que lâapplication des paramĂštres dans des conditions extrĂȘmes fixĂ©s par la norme EN peuvent mener Ă des diffĂ©rences de rĂ©sultats significatifs. La comparaison des mĂ©thodes des deux normes (EN et SN), avec des masses de bitume rĂ©cupĂ©rĂ©s semblables de 150 g, a mis en Ă©vidence une parfaite corrĂ©lation sur une gamme de bitumes purs et dâenrobĂ©s trĂšs diffĂ©rents (bitumes purs et Bmp). Les essais comparatifs entre les 2 laboratoires ont montrĂ© une trĂšs bonne corrĂ©lation. Ces rĂ©sultats ont pu ĂȘtre obtenus par lâharmonisation des mĂ©thodes de prĂ©paration des Ă©chantillons et des mĂ©thodes dâessais. Plusieurs essais rĂ©alisĂ©s Ă des pĂ©riodes diffĂ©rentes sur des produits stockĂ©s Ă lâabri de la lumiĂšre et Ă une tempĂ©rature stable ont permis de mettre en Ă©vidence lâeffet du vieillissement dans le temps. La caractĂ©risation des liants aprĂšs rĂ©cupĂ©ration a montrĂ© quâil fallait ĂȘtre trĂšs prudent en ce qui concerne le phĂ©nomĂšne de restructuration du liant aprĂšs essai. Un dĂ©lai de repos de plusieurs heures (environ 6 heures) paraĂźt nĂ©cessaire pour obtenir des valeurs de pĂ©nĂ©tration stabilisĂ©es, en particulier pour le bitume B 80/100 semi-soufflĂ© de Cressier
Agreement among Health Care Professionals in Diagnosing Case Vignette-Based Surgical Site Infections
OBJECTIVE: To assess agreement in diagnosing surgical site infection (SSI) among healthcare professionals involved in SSI surveillance. METHODS: Case-vignette study done in 2009 in 140 healthcare professionals from seven specialties (20 in each specialty, Anesthesiologists, Surgeons, Public health specialists, Infection control physicians, Infection control nurses, Infectious diseases specialists, Microbiologists) in 29 University and 36 non-University hospitals in France. We developed 40 case-vignettes based on cardiac and gastrointestinal surgery patients with suspected SSI. Each participant scored six randomly assigned case-vignettes before and after reading the SSI definition on an online secure relational database. The intraclass correlation coefficient (ICC) was used to assess agreement regarding SSI diagnosis on a seven-point Likert scale and the kappa coefficient to assess agreement for superficial or deep SSI on a three-point scale. RESULTS: Based on a consensus, SSI was present in 21 of 40 vignettes (52.5%). Intraspecialty agreement for SSI diagnosis ranged across specialties from 0.15 (95% confidence interval, 0.00-0.59) (anesthesiologists and infection control nurses) to 0.73 (0.32-0.90) (infectious diseases specialists). Reading the SSI definition improved agreement in the specialties with poor initial agreement. Intraspecialty agreement for superficial or deep SSI ranged from 0.10 (-0.19-0.38) to 0.54 (0.25-0.83) (surgeons) and increased after reading the SSI definition only among the infection control nurses from 0.10 (-0.19-0.38) to 0.41 (-0.09-0.72). Interspecialty agreement for SSI diagnosis was 0.36 (0.22-0.54) and increased to 0.47 (0.31-0.64) after reading the SSI definition. CONCLUSION: Among healthcare professionals evaluating case-vignettes for possible surgical site infection, there was large disagreement in diagnosis that varied both between and within specialties
Synthetic RGDS peptide attenuates lipopolysaccharide-induced pulmonary inflammation by inhibiting integrin signaled MAP kinase pathways
<p>Abstract</p> <p>Background</p> <p>Synthetic peptides containing the RGD sequence inhibit integrin-related functions in different cell systems. Here, we investigated the effects of synthetic Arg-Gly-Asp-Ser (RGDS) peptide on key inflammatory responses to intratracheal (<it>i.t.</it>) lipopolysaccharide (LPS) treatment and on the integrin signaled mitogen-activated protein (MAP) kinase pathway during the development of acute lung injury.</p> <p>Methods</p> <p>Saline or LPS (1.5 mg/kg) was administered <it>i.t. </it>with or without a single dose of RGDS (1, 2.5, or 5 mg/kg, i.p.), anti-α<sub>v </sub>or anti-ÎČ<sub>3 </sub>mAb (5 mg/kg, i.p.). Mice were sacrificed 4 or 24 h post-LPS.</p> <p>Results</p> <p>A pretreatment with RGDS inhibited LPS-induced increases in neutrophil and macrophage numbers, total protein levels and TNF-α and MIP-2 levels, and matrix metalloproteinase-9 activity in bronchoalveolar lavage (BAL) fluid at 4 or 24 h post-LPS treatment. RGDS inhibited LPS-induced phosphorylation of focal adhesion kinase and MAP kinases, including ERK, JNK, and p38 MAP kinase, in lung tissue. Importantly, the inhibition of the inflammatory responses and the kinase pathways were still evident when this peptide was administered 2 h after LPS treatment. Similarly, a blocking antibody against integrin α<sub>v </sub>significantly inhibited LPS-induced inflammatory cell migration into the lung, protein accumulation and proinflammatory mediator production in BAL fluid, at 4 or 24 h post-LPS. Anti-ÎČ<sub>3 </sub>also inhibited all LPS-induced inflammatory responses, except the accumulation of BAL protein at 24 h post-LPS.</p> <p>Conclusion</p> <p>These results suggest that RGDS with high specificity for α<sub>v</sub>integrins attenuates inflammatory cascade during LPS-induced development of acute lung injury.</p
Extracellular Superoxide Dismutase Protects Histoplasma Yeast Cells from Host-Derived Oxidative Stress
In order to establish infections within the mammalian host, pathogens must protect themselves against toxic reactive oxygen species produced by phagocytes of the immune system. The fungal pathogen Histoplasma capsulatum infects both neutrophils and macrophages but the mechanisms enabling Histoplasma yeasts to survive in these phagocytes have not been fully elucidated. We show that Histoplasma yeasts produce a superoxide dismutase (Sod3) and direct it to the extracellular environment via N-terminal and C-terminal signals which promote its secretion and association with the yeast cell surface. This localization permits Sod3 to protect yeasts specifically from exogenous superoxide whereas amelioration of endogenous reactive oxygen depends on intracellular dismutases such as Sod1. While infection of resting macrophages by Histoplasma does not stimulate the phagocyte oxidative burst, interaction with polymorphonuclear leukocytes (PMNs) and cytokine-activated macrophages triggers production of reactive oxygen species (ROS). Histoplasma yeasts producing Sod3 survive co-incubation with these phagocytes but yeasts lacking Sod3 are rapidly eliminated through oxidative killing similar to the effect of phagocytes on Candida albicans yeasts. The protection provided by Sod3 against host-derived ROS extends in vivo. Without Sod3, Histoplasma yeasts are attenuated in their ability to establish respiratory infections and are rapidly cleared with the onset of adaptive immunity. The virulence of Sod3-deficient yeasts is restored in murine hosts unable to produce superoxide due to loss of the NADPH-oxidase function. These results demonstrate that phagocyte-produced ROS contributes to the immune response to Histoplasma and that Sod3 facilitates Histoplasma pathogenesis by detoxifying host-derived reactive oxygen thereby enabling Histoplasma survival
Mathematical Modelling as a Proof of Concept for MPNs as a Human Inflammation Model for Cancer Development
<p><b>Left:</b> Typical development in stem cells (top panel A) and mature cells (bottom panel B). Healthy hematopoietic cells (full blue curves) dominate in the early phase where the number of malignant cells (stipulated red curves) are few. The total number of cells is also shown (dotted green curves). When a stem cell mutates without repairing mechanisms, a slowly increasing exponential growth starts. At a certain stage, the malignant cells become dominant, and the healthy hematopoietic cells begin to show a visible decline. Finally, the composition between the cell types results in a takeover by the malignant cells, leading to an exponential decline in hematopoietic cells and ultimately their extinction. The development is driven by an approximately exponential increase in the MPN stem cells, and the development is closely followed by the mature MPN cells. <b>Right:</b> B)The corresponding allele burden (7%, 33% and 67% corresponding to ET, PV, and PMF, respectively) defined as the ratio of MPN mature cells to the total number of mature cells.</p
Institutional shared resources and translational cancer research
The development and maintenance of adequate shared infrastructures is considered a major goal for academic centers promoting translational research programs. Among infrastructures favoring translational research, centralized facilities characterized by shared, multidisciplinary use of expensive laboratory instrumentation, or by complex computer hardware and software and/or by high professional skills are necessary to maintain or improve institutional scientific competitiveness. The success or failure of a shared resource program also depends on the choice of appropriate institutional policies and requires an effective institutional governance regarding decisions on staffing, existence and composition of advisory committees, policies and of defined mechanisms of reporting, budgeting and financial support of each resource. Shared Resources represent a widely diffused model to sustain cancer research; in fact, web sites from an impressive number of research Institutes and Universities in the U.S. contain pages dedicated to the SR that have been established in each Center, making a complete view of the situation impossible. However, a nation-wide overview of how Cancer Centers develop SR programs is available on the web site for NCI-designated Cancer Centers in the U.S., while in Europe, information is available for individual Cancer centers. This article will briefly summarize the institutional policies, the organizational needs, the characteristics, scientific aims, and future developments of SRs necessary to develop effective translational research programs in oncology
The Compact Linear Collider (CLIC) - 2018 Summary Report
The Compact Linear Collider (CLIC) is a TeV-scale high-luminosity linear collider under development at CERN. Following the CLIC conceptual design published in 2012, this report provides an overview of the CLIC project, its current status, and future developments. It presents the CLIC physics potential and reports on design, technology, and implementation aspects of the accelerator and the detector. CLIC is foreseen to be built and operated in stages, at centre-of-mass energies of 380 GeV, 1.5 TeV and 3 TeV, respectively. CLIC uses a two-beam acceleration scheme, in which 12 GHz accelerating structures are powered via a high-current drive beam. For the first stage, an alternative with X-band klystron powering is also considered. CLIC accelerator optimisation, technical developments and system tests have resulted in an increased energy efficiency (power around 170 MW) for the 380 GeV stage, together with a reduced cost estimate at the level of 6 billion CHF. The detector concept has been refined using improved software tools. Significant progress has been made on detector technology developments for the tracking and calorimetry systems. A wide range of CLIC physics studies has been conducted, both through full detector simulations and parametric studies, together providing a broad overview of the CLIC physics potential. Each of the three energy stages adds cornerstones of the full CLIC physics programme, such as Higgs width and couplings, top-quark properties, Higgs self-coupling, direct searches, and many precision electroweak measurements. The interpretation of the combined results gives crucial and accurate insight into new physics, largely complementary to LHC and HL-LHC. The construction of the first CLIC energy stage could start by 2026. First beams would be available by 2035, marking the beginning of a broad CLIC physics programme spanning 25-30 years
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