Abstract
After the Phase-2 high-luminosity upgrade to the Large Hadron Collider (LHC), the collision rate and therefore the background rate will significantly increase, particularly in the high η ...region. To improve both the tracking and triggering of muons, the Compact Muon Solenoid (CMS) Collaboration plans to install triple-layer Gas Electron Multiplier (GEM) detectors in the CMS muon endcaps. Demonstrator GEM detectors were installed in CMS during 2017 to gain operational experience and perform a preliminary investigation of detector performance. We present the results of triple-GEM detector performance studies performed in situ during normal CMS and LHC operations in 2018. The distribution of cluster size and the efficiency to reconstruct high
p
T
muons in proton-proton collisions are presented as well as the measurement of the environmental background
rate to produce hits in the GEM detector.
The CMS muon system in the region with 2.03<|η|<2.82 is characterized by a very harsh radiation environment which can generate hit rates up to 144 kHz/cm2 and an integrated charge of 8 C/cm2 over ten ...years of operation. In order to increase the detector performance and acceptance for physics events including muons, a new muon station (ME0) has been proposed for installation in that region. The technology proposed is Triple—Gas Electron Multiplier (Triple-GEM), which has already been qualified for the operation in the CMS muon system. However, an additional set of studies focused on the discharge probability is necessary for the ME0 station, because of the large radiation environment mentioned above. A test was carried out in 2017 at the Cern High energy AcceleRator Mixed (CHARM) facility, with the aim of giving an estimation of the discharge probability of Triple-GEM detectors in a very intense radiation field environment, similar to the one of the CMS muon system. A dedicated standalone Geant4 simulation was performed simultaneously, to evaluate the behavior expected in the detector exposed to the CHARM field. The geometry of the detector has been carefully reproduced, as well as the background field present in the facility. This paper presents the results obtained from the Geant4 simulation, in terms of sensitivity of the detector to the CHARM environment, together with the analysis of the energy deposited in the gaps and of the processes developed inside the detector. The discharge probability test performed at CHARM will be presented, with a complete discussion of the results obtained, which turn out to be consistent with measurements performed by other groups.
A temperature monitoring system based on fibre Bragg grating (FBG) fibre optic sensors has been developed for the gas electron multiplier (GEM) chambers of the Compact Muon Solenoid (CMS) detector. ...The monitoring system was tested in prototype chambers undergoing a general test of the various technological solutions adopted for their construction. The test lasted about two years and was conducted with the chambers being installed in the CMS detector and operated during regular experimental running. In this paper, we present test results that address the choice of materials and procedures for the production and installation of the FBG temperature monitoring system in the final GEM chambers.
Gas Electron Multiplier (GEM) technology, in particular triple-GEM, was selected for the upgrade of the CMS endcap muon system following several years of intense effort on R&D. The triple-GEM ...chambers (GE1/1) are being installed at station 1 during the second long shutdown with the goal of reducing the Level-1 muon trigger rate and improving the tracking performance in the harsh radiation environment foreseen in the future LHC operation 1. A first installation of a demonstrator system started at the beginning of 2017: 10 triple-GEM detectors were installed in the CMS muon system with the aim of gaining operational experience and demonstrating the integration of the GE1/1 system into the trigger. In this context, a dedicated Detector Control System (DCS) has been developed, to control and monitor the detectors installed and integrating them into the CMS operation. This paper presents the slice test DCS, describing in detail the different parts of the system and their implementation.
The spinal cord is one of the sites where non-steroidal anti-inflammatory drugs (NSAIDs) act to produce analgesia and antinociception. Expression of cyclooxygenase(COX)-1 and COX-2 in the spinal cord ...and primary afferents suggests that NSAIDs act here by inhibiting the synthesis of prostaglandins (PGs). Basal release of PGD sub(2), PGE sub(2), PGF sub(2 alpha ) and PGI sub(2) occurs in the spinal cord and dorsal root ganglia. Prostaglandins then bind to G-protein-coupled receptors located in intrinsic spinal neurons (receptor types DP and EP2) and primary afferent neurons (EP1, EP3, EP4 and IP). Acute and chronic peripheral inflammation, interleukins and spinal cord injury increase the expression of COX-2 and release of PGE sub(2) and PGI sub(2). By activating the cAMP and protein kinase A pathway, PGs enhance tetrodotoxin-resistant sodium currents, inhibit voltage-dependent potassium currents and increase voltage-dependent calcium inflow in nociceptive afferents. This decreases firing threshold, increases firing rate and induces release of excitatory amino acids, substance P, calcitonin gene-related peptide (CGRP) and nitric oxide. Conversely, glutamate, substance P and CGRP increase PG release. Prostaglandins also facilitate membrane currents and release of substance P and CGRP induced by low pH, bradykinin and capsaicin. All this should enhance elicitation and synaptic transfer of pain signals in the spinal cord. Direct administration of PGs to the spinal cord causes hyperalgesia and allodynia, and some studies have shown an association between induction of COX-2, increased PG release and enhanced nociception. NSAIDs diminish both basal and enhanced PG release in the spinal cord. Correspondingly, spinal application of NSAIDs generally diminishes neuronal and behavioral responses to acute nociceptive stimulation, and always attenuates behavioral responses to persistent nociception. Spinal application of specific COX-2 inhibitors sometimes diminishes behavioral responses to persistent nociception.
Murine erythroleukemia (MEL) cells undergo erythroid differentiation in vitro when treated with hexamethylene bisacetamide (HMBA). To identify genes involved in the commitment of MEL cells to ...differentiate, we screened a cDNA library constructed from HMBA-induced cells by differential hybridization and isolated GTPase
Ran as a down-regulated gene. We observed that
Ran was expressed in a biphasic mode. Following a decrease in mRNA level during the initial hours of induction,
Ran re-expressed at 24–48
h, and gradually declined again. To investigate the role of
Ran during MEL differentiation we constructed MEL transfectants capable to express or block
Ran mRNA production constitutively. No effects were observed on cell growth and proliferation. Blockage of Ran, however, interfered with MEL cell differentiation resulting in a decrease of cell survival in the committed population.
El presente artículo contiene los resultados del diagnóstico de los Programas Educación en Consumo Sostenible y Mercados Verdes de la Estrategia Promoción al Consumo Sostenible de la Política de ...Producción Sostenible del Distrito Capital (1) para el Sector empresarial. El diagnóstico permitió evidenciar que desde las acciones priorizadas propuestas en el Plan de acción 2004 de la Política de Producción Sostenible del Distrito Capital hubo cumplimiento del Programa de Educación en Consumo Sostenible pero no para el Programa de Mercados Verdes, a pesar que hay otras acciones que permiten la identificación de resultados relacionados. A su vez, se sugiere el desarrollo de indicadores a mediano y largo plazo de los programas, dar a conocer la Política de Producción Sostenible del Distrito Capital desde el Programa de Gestión Ambiental Empresarial (2), y el fomento de la cultura del Consumo Sostenible y los Mercados Verdes.
El presente artículo contiene los resultados del diagnóstico de los Programas Educación en Consumo Sostenible y Mercados Verdes de la Estrategia Promoción al Consumo Sostenible de la Política de ...Producción Sostenible del Distrito Capital (1) para el Sector empresarial.
Abstract This article contains the results of Diagnosis of Education Programs in Sustainable Consumption and Green Marketing Promotion Strategy for Sustainable Consumption Policy Sustainable ...Production Capital District 1 for the corporate sector was developed. The diagnosis allowed noting from the priority actions proposed in the Action Plan 2004 Policy for Sustainable Production Capital District was compliance with the Education Program Sustainable consumption but not for Green Markets Programme, although there are other actions that enable identification of related results. In turn, the development of indicators in the medium and long term programs to publicize the Policy on Sustainable Production from the Capital District Environmental Business Management Program 2, and the promotion of the culture of the Sustainable Consumption and Markets suggests greens.
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