4,317 research outputs found

    A study of gas contaminants and interaction with materials in RPC closed loop systems

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    Resistive Plate Counters (RPC) detectors at the Large Hadron Collider (LHC) experiments use gas recirculation systems to cope with large gas mixture volumes and costs. In this paper a long-term systematic study about gas purifiers, gas contaminants and detector performance is discussed. The study aims at measuring the lifetime of purifiers with unused and used cartridge material along with contaminants release in the gas system. During the data-taking the response of several RPC double-gap detectors was monitored in order to characterize the correlation between dark currents, filter status and gas contaminants

    CMS endcap RPC gas gap production for upgrade

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    The CMS experiment will install a RE4 layer of 144 new Resistive Plate Chambers (RPCs) on the existing york YE3 at both endcap regions to trigger high momentum muons from the proton-proton interaction. In this paper, we present the detailed procedures used in the production of new RPC gas gaps adopted in the CMS upgrade. Quality assurance is enforced as ways to maintain the same quality of RPC gas gaps as the existing 432 endcap RPC chambers that have been operational since the beginning of the LHC operation

    Sustainable and green persulfate-based chemiluminescent method for on-site estimation of chemical oxygen demand in waters

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    The standard method for estimating the chemical oxygen demand (COD) of water bodies uses dichromate as the main oxidant, a chemical agent whose use has been restricted in the European Union since 2017. This method is hazardous, time-consuming, and burdensome to adapt to on-site measurements. As an alternative and following the current trends of sustainable and green chemistry, a method using the less toxic reagent sodium persulfate as the oxidizing agent has been developed. In this method an excess of persulfate, activated through heating in an alkaline solution, oxidizes the chemically degradable organic fraction through a 2-step radical mechanism. The remaining persulfate is evaluated by chemiluminescence (CL) using luminol and a portable charge-coupled device (CCD) camera. The method provided quantitative recoveries and a sample throughput of >60 samples h. It was validated in river water samples by comparison of COD estimations with the standard dichromate method (R = 0.973, p < 0.05) and with a UV–Vis permanganate-based method (R = 0.9998, p < 0.05), the latter being also used for drinking waters. The proposed method is a sustainable and green alternative to the previous used methods. Overall, the method using activated persulfate is suitable for use as COD quantitation/screening tool in surface waters. Considering that its main components are portable, it can be ultimately adapted for in situ analysis at the point of need

    Performance of the Gas Gain Monitoring system of the CMS RPC muon detector and effective working point fine tuning

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    The Gas Gain Monitoring (GGM) system of the Resistive Plate Chamber (RPC) muon detector in the Compact Muon Solenoid (CMS) experiment provides fast and accurate determination of the stability in the working point conditions due to gas mixture changes in the closed loop recirculation system. In 2011 the GGM began to operate using a feedback algorithm to control the applied voltage, in order to keep the GGM response insensitive to environmental temperature and atmospheric pressure variations. Recent results are presented on the feedback method used and on alternative algorithms

    EFFECT OF HIGH INTENSITY TRAINING AND ISOINERTIAL TRAINING ON INTERMUSCULAR ADIPOSE TISSUE IN OLDER ADULTS

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    Introduction Recent findings suggest that, in elderly, Intermuscular Adipose Tissue (IMAT) may be associated with inactivity and that exercise training may be able to mitigate the content of IMAT (Murphy et al., 2012; Santanasto et al., 2011). The purpose was to determine how IMAT can be influenced by exercise and if a greater reduction in IMAT occurs with concurrent aerobic High Intensity Training (HIT) and Isoinertial Resistance Training (IRT). Methods 12 moderately active older adults (age: 69.4±4.3 yy; weight: 78.5±10.5 kg; height: 171.2±5.3 cm; BMI: 22.9±2.7 kg/m2; V'O2max: 29.5±4.1 mL/kg/min) were exposed to 8 weeks of: i) HIT training with 7 two-minute cycling repetitions at 90% of V'O2max, 3 times/week and, after 4 months, ii) IRT performed with an isoinertial leg press (YoYo Technology AB) comprised 4×7 maximal concentric-eccentric knee extensions, 3 times/week. MRI of the mid-thigh was examined to determine changes in muscle composition (Cross Sectional Area (CSA) and IMAT) after exercise intervention using SliceOmatic image analysis software (Rossi et al., 2010). IMAT was defined as adipose tissue area visible between quadriceps muscle groups. Results Quadriceps CSA increased significantly after HIT and after IRT by 6% (P<0.05) and 7% (P<0.05) respectively. IMAT decreased after HIT and IRT by 31% (P<0.05) and 41% (P<0.05) respectively. Net thigh lean mass increased significantly after both training by 10% (P<0.05). Discussion Our data, in contrast with Jacobs (2014) and Goodpaster (2008) but in agreement with other previous studies (Murphy et al., 2012; Santanasto et al., 2011), show that IMAT decrease after a 8 weeks exercise intervention in older adults both after HIT and IRT. Preliminary data show that exercise training performed at high intensity in older adults may contrast skeletal muscle fat infiltration. Our study is non-randomized, not-counterbalanced and limited by small sample size: additional studies are needed to determine the most effective exercise (type, intensity, modalities) able to decrease IMAT and how this decrease may positively affect health in elderly

    Smartphone biosensor for point-of-need chemiluminescence detection of ochratoxin A in wine and coffee

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    Exposure to mycotoxins, which may contaminate food and feed commodities, represents a serious health risk for consumers. Ochratoxin A (OTA) is one of the most abundant and toxic mycotoxins, thus specific regulations for fixing its maximum admissible levels in foodstuff have been established. Lateral Flow ImmunoAssay (LFIA)-based devices have been proposed as screening tools to avoid OTA contamination along the whole food chain. We report a portable, user-friendly smartphone-based biosensor for the detection and quantification of OTA in wine and instant coffee, which combines the LFIA approach with chemiluminescence (CL) detection. The device employs the smartphone camera as a light detector and uses low-cost, disposable analytical cartridges containing the LFIA strip and all the necessary reagents. The analysis can be carried out at the point of need by non-specialized operators through simple manual operations. The biosensor allows OTA quantitative detection in wine and coffee samples up to 25 μg L−1 and with limits of detection of 0.3 and 0.1 μg L−1, respectively, which are below the European law-fixed limits. These results demonstrate that the developed device can be used for routine monitoring of OTA contamination, enabling rapid and reliable identification of positive samples requiring confirmatory analysis

    Respostas fisiológicas de bovinos Nelore, Senepol x Nelore e Angus x Nelore submetidos a teste de tolerância ao calor. I

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    a cadeia produtiva pecuária brasileira tem vivenciado aumento na introdução de raças taurinas (adaptadas e não adaptadas) e no uso de cruzamento industrial, todavia, pouco se sabe sobre a adaptabilidade desses grupos genéticos e dos produtos de seus cruzamentos às condições brasileiras. Assim sendo, o objetivo neste estudo é avaliar as respostas fisiológicas relacionadas à adaptabilidade de bovinos Nelore (NE) e cruzados Angus x Nelore (TA) e Senepol x Nelore (SN) submetidos a um teste de tolerância ao calor. O estudo foi executado na Embrapa Pecuária Sudeste, em São Carlos, SP, utilizando 15 fêmeas de cada grupo genético, com aproximadamente 14 meses de idade. Os animais foram avaliados em dias quentes de verão, sendo realizadas medidas de temperatura retal, de freqüência respiratória e de taxa de sudação. Nos dias do teste, a média do índice de temperatura e umidade (ITU), às 13 horas, foi de 78,9. Os animais cruzados Angus x Nelore apresentaram maior freqüência respiratória que os animais dos outros grupos genéticos e alta taxa de sudação, não diferindo do grupo Nelore. Os animais do grupo Senepol x Nelore apresentaram valores de taxa de sudação inferiores ao dos outros dois grupos (P<0,05). Esses resultados mostram que os animais Senepol x Nelore foram mais eficientes para manter a homeostase corporal, apresentando menores valores de freqüência respiratória e de taxa de sudação. Todavia os três grupos genéticos apresentaram valores semelhantes de temperatura corporal no teste de tolerância ao calor

    A real-world study on unmet medical needs in triptan-treated migraine: Prevalence, preventive therapies and triptan use modification from a large Italian population along two years

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    Although migraine is a disabling neurological condition that causes important disability, it remains an area of underdiagnosis and undertreatment worldwide. The aim of this study was to depict the burden of the unmet medical needs in migraine treated with triptans in a large Italian population

    Green Infrastructure Assessment Tools for Varying Scales in Coastal South Carolina

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    2010 S.C. water Resources Conference - Science and Policy Challenges for a Sustainable Futur

    The Upgrade of the CMS RPC System during the First LHC Long Shutdown

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    The CMS muon system includes in both the barrel and endcap region Resistive Plate Chambers (RPC). They mainly serve as trigger detectors and also improve the reconstruction of muon parameters. Over the years, the instantaneous luminosity of the Large Hadron Collider gradually increases. During the LHC Phase 1 (~first 10 years of operation) an ultimate luminosity is expected above its design value of 10^34/cm^2/s at 14 TeV. To prepare the machine and also the experiments for this, two long shutdown periods are scheduled for 2013-2014 and 2018-2019. The CMS Collaboration is planning several detector upgrades during these long shutdowns. In particular, the muon detection system should be able to maintain a low-pT threshold for an efficient Level-1 Muon Trigger at high particle rates. One of the measures to ensure this, is to extend the present RPC system with the addition of a 4th layer in both endcap regions. During the first long shutdown, these two new stations will be equipped in the region |eta|<1.6 with 144 High Pressure Laminate (HPL) double-gap RPCs operating in avalanche mode, with a similar design as the existing CMS endcap chambers. Here, we present the upgrade plans for the CMS RPC system for the fist long shutdown, including trigger simulation studies for the extended system, and details on the new HPL production, the chamber assembly and the quality control procedures.Comment: 9 pages, 6 figures, presented by M.Tytgat at the XI workshop on Resistive Plate Chambers and Related Detectors (RPC2012), INFN - Laboratori Nazionali di Frascati, February 5-10, 201
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