A Comparative Numerical Study on GEM, MHSP and MSGC

In this work, we have tried to develop a detailed understanding of the physical processes occurring in those variants of Micro Pattern Gas Detectors (MPGDs) that share micro hole and micro strip geometry, like GEM, MHSP and MSGC etc. Some of the important and fundamental characteristics of these detectors such as gain, transparency, efficiency and their operational dependence on different device parameters have been estimated following detailed numerical simulation of the detector dynamics. We have used a relatively new simulation framework developed especially for the MPGDs that combines packages such as GARFIELD, neBEM, MAGBOLTZ and HEED. The results compare closely with the available experimental data. This suggests the efficacy of the framework to model the intricacies of these micro-structured detectors in addition to providing insight into their inherent complex dynamical processes

Increased expression of interleukin-22 in patients with giant cell arteritis

GCA is characterized by arterial remodelling driven by inflammation. IL-22 is an attractive cytokine which acts at the crosstalk between immune and stromal cells. We hypothesized that IL-22 might be induced in GCA and might be involved in disease pathogenesis

Ectopic expression of CXCL13, BAFF, APRIL and LT-ß is associated with artery tertiary lymphoid organs in giant cell arteritis

Objectives To investigate whether artery tertiary lymphoid organs (ATLOs) are present in giant cell arteritis (GCA) and that their formation is associated with the ectopic expression of constitutive lymphoid tissue-homing chemokines. Methods Reverse transcriptase PCR, immunohistochemical and immunofluorescence analysis were used to determine the presence of ectopic ATLOs in GCA and the expression of chemokines/chemokine receptors and cytokines involved in lymphoneogenesis in the temporal artery samples obtained from 50 patients with GCA and 30 controls. The presence of lymphatic conduits, of follicular dendritic cells (FDCs) precursors and lymphoid tissue inducer cells was also investigated. Finally, expression of CXCL13, B cell activating factor (BAFF), a proliferation-inducing ligand (APRIL) and CCL21 by isolated myofibroblasts was evaluated before and after stimulation with Toll-like receptors (TLRs) agonists and cytokines. Results ATLOs were observed in the media layer of 60% of patients with GCA in close proximity to high endothelial venules and independently by the age of patients and the presence of atherosclerosis. ATLO formation was also accompanied by the expression of CXCL13, BAFF, a proliferation-inducing ligand (APRIL), lymphotoxin (LT)-ß, interleukin (IL)-17 and IL-7, the presence of FDC precursors and of lymphoid conduits. Stimulation of myofibroblasts with TLR agonists and cytokines resulted in the upregulation of BAFF and CXCL13. Conclusions ATLOs occur in the inflamed arteries of patients with GCA possibly representing the immune sites where immune responses towards unknown arterial wall-derived antigens may be organised

Nurse-like cells control the activity of chronic lymphocytic leukemia b cells via galectin-1

Accumulation of neoplastic cells in chronic lymphocytic leukemia (CLL) is conditioned by a variety of signals delivered by accompanying cells in lymphoid tissues. Here we examined the relevance of galectin-1 (Gal-1), a glycan-binding protein with immunoregulatory activity, within the CLL microenvironment. We found that monocytes in peripheral blood and stromal and myeloid cells in bone marrow biopsies are the main source of Gal1. Knocking down Gal1 in adherent nurse-like cells differentiated in vitro decreased the expression of activation markers (CD80, CD86, CD25) and mRNA levels of IL10 and CCL3 in CLL cells. The concentration of Gal1 in plasma was increased in CLL patients compared to healthy subjects. Likewise, we found a higher expression of Gal1 in bone marrow biopsies from patients with progressive disease. These results provide the first evidence of a role for Gal-1 in CLL cell differentiation and its expression in accompanying myeloid cells.Fil: Croci Russo, Diego Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); ArgentinaFil: Morande, Pablo Elías. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental; ArgentinaFil: Dergan Dylon, Leonardo Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); ArgentinaFil: Borge, Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental; ArgentinaFil: Toscano, Marta Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); ArgentinaFil: Stupirski, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); ArgentinaFil: Bezares, R. F.. Hospital General de Agudos "Dr T. Alvarez"; ArgentinaFil: Avalos, J. S.. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Narbaitz, M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental; ArgentinaFil: Gamberale, Romina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental; ArgentinaFil: Rabinovich, Gabriel Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); ArgentinaFil: Giordano, Mirta Nilda. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental; Argentin

An overview of the design, construction and performance of large area triple-GEM prototypes for future upgrades of the CMS forward muon system

GEM detectors are used in high energy physics experiments given their good spatial resolution, high rate capability and radiation hardness. An international collaboration is investigating the possibility of covering the 1.6 < vertical bar eta vertical bar < 2.4 region of the CMS muon endcaps with large-area triple-GEM detectors. The CMS high-eta area is actually not fully instrumented, only Cathode Strip Chamber (CSC) are installed. The vacant area presents an opportunity for a detector technology able to to cope with the harsh radiation environment; these micropattern gas detectors are an appealing option to simultaneously enhance muon tracking and triggering capabilities in a future upgrade of the CMS detector. A general overview of this feasibility study is presented. Design and construction of small (10cm x 10cm) and full-size trapezoidal (1m x 0.5m) triple-GEM prototypes is described. Results from measurements with x-rays and from test beam campaigns at the CERN SPS is shown for the small and large prototypes. Preliminary simulation studies on the expected muon reconstruction and trigger performances of this proposed upgraded muon system are reported

Multi-output multilevel best linear unbiased estimators via semidefinite programming

Multifidelity forward uncertainty quantification (UQ) problems often involve multiple quantities of interest and heterogeneous models (e.g., different grids, equations, dimensions, physics, surrogate and reduced-order models). While computational efficiency is key in this context, multi-output strategies in multilevel/multifidelity methods are either sub-optimal or non-existent. In this paper we extend multilevel best linear unbiased estimators (MLBLUE) to multi-output forward UQ problems and we present new semidefinite programming formulations for their optimal setup. Not only do these formulations yield the optimal number of samples required, but also the optimal selection of low-fidelity models to use. While existing MLBLUE approaches are single-output only and require a non-trivial nonlinear optimization procedure, the new multi-output formulations can be solved reliably and efficiently. We demonstrate the efficacy of the new methods and formulations in practical UQ problems with model heterogeneity.Comment: 22 pages, 5 figures, 3 table

Attached cavitation in a laminar separation bubble

International audienceThe present study aims at studying the inception, the growth and the potential unsteady dynamics of attached vapour cavities in large laminar separation bubbles. A viscous silicon oil has been used in a venturi geometry in order to explore the flow for Reynolds numbers ranging from Re = 800 to Re = 2000. The results show that at low Reynolds number the attached sheets that are attributed to cavitation do not have any obvious dynamics and abruptly transit to supercavitation when lowering the cavitation number. For Re 1200, cavitating vortices are intermittently observed in the wake of the attached cavity with no clear period. Finally, a periodic shedding/shrinking of the main cavity is first observed for Re 1400, in a narrow range of cavitation numbers, together with a slower growth of the cavities when lowering the cavitation number. This regime is then present at higher Reynolds numbers, in a wider range of cavitation numbers

Dietary Strategies for Management of Metabolic Syndrome: Role of Gut Microbiota Metabolites

Metabolic syndrome (MetS) is a complex pathophysiological state with incidence similar to that of a global epidemic and represents a risk factor for the onset of chronic non-communicable degenerative diseases (NCDDs), including cardiovascular disease (CVD), type 2 diabetes mellitus, chronic kidney disease, and some types of cancer. A plethora of literature data suggest the potential role of gut microbiota in interfering with the host metabolism, thus influencing several MetS risk factors. Perturbation of the gut microbiota's composition and activity, a condition known as dysbiosis, is involved in the etiopathogenesis of multiple chronic diseases. Recent studies have shown that some micro-organism-derived metabolites (including trimethylamine N-oxide (TMAO), lipopolysaccharide (LPS) of Gram-negative bacteria, indoxyl sulfate and p-cresol sulfate) induce subclinical inflammatory processes involved in MetS. Gut microbiota's taxonomic species or abundance are modified by many factors, including diet, lifestyle and medications. The main purpose of this review is to highlight the correlation between different dietary strategies and changes in gut microbiota metabolites. We mainly focus on the validity/inadequacy of specific dietary patterns to reduce inflammatory processes, including leaky gut and subsequent endotoxemia. We also describe the chance of probiotic supplementation to interact with the immune system and limit negative consequences associated with MetS

Preventive conservation plan for a group of bronze sculptures from the Gori Art Collection

This paper deals with a multi-analytical and long-term in-situ monitoring campaign for evaluating the state of conservation of some outdoor contemporary bronze sculptures of the environmental Gori Collection, at the Fattoria di Celle, located in the municipality of Santomato, Pistoia, Italy. Digital 3D models of the Cavaliere and of one of the thirty-three figures of Katharsis have been made by means of photogrammetry in order to characterize the artworks. On the same sculptures, the chemical composition of the corrosion patinas has been determined by Raman spectroscopy. Moreover, the protective effectiveness of the corrosion products layer has been assessed by means of electrochemical impedance spectroscopy (EIS). The analytical data obtained in the monitoring campaign, still in progress, are discussed as a function of the exposure time and conditions to outdoor environment of the works of art