189 research outputs found

    What do we learn from Resonance Production in Heavy Ion Collisions?

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    Resonances with their short life time and strong coupling to the dense and hot medium are suggested as a signature of the early stage of the fireball created in a heavy ion collision \cite{rap00,lut01,lut02}. The comparison of resonances with different lifetimes and quark contents may give information about time evolution and density and temperature of during the expanding of fireball medium. Resonances in elementary reactions have been measured since 1960. Resonance production in elementary collisions compared with heavy ion collisions where we expect to create a hot and dense medium may show the direct of influence of the medium on the resonances. This paper shows a selection of the recent resonance measurements from SPS and RHIC heavy ion colliders.Comment: 10 pages, 8 figures, HotQuarks 2004 conference proceeding

    Resonance production in heavy ion collisions

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    Recent results of resonance production from RHIC at sNN=\sqrt{s_{\rm NN}} = 200 GeV and SPS at sNN=\sqrt{s_{\rm NN}} = 17 GeV are presented and discussed in terms of the evolution and freeze-out conditions of a hot and dense fireball medium. Yields and spectra are compared with thermal model predictions at chemical freeze-out. Deviations in the low transverse momentum region of the resonance spectrum of the hadronic decay channel, suggest a strongly interaction hadronic phase between chemical and kinetic freeze-out. Microscopic models including resonance rescattering and regeneration are able to describe the trend of the data. The magnitude of the regeneration cross sections for different inverse decay channels are discussed. Model calculations which include elastic hadronic interactions between chemical freeze-out and thermal freeze-out based on the K(892)/K and Λ\Lambda(1520)/Λ\Lambda ratios suggest a time between two freeze-outs surfaces of Δτ>\Delta \tau> 4 fm/c. The difference in momentum distributions and yields for the ϕ\phi(1020) resonance reconstructed from the leptonic and hadronic decay channels at SPS energy are discussed taking into account the impact of a hadronic phase and possible medium modifications.Comment: 8 pages, 4 figures, conference proceedings (SQM2004

    Anålise da estrutura e composição de uma floresta em processo de restauração no município de IgarapÊ-Açu, Parå.

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    Após fortes distúrbios, uma årea degradada perde os seus meios bióticos de regeneração, necessitando de forte intervenção antrópica para que seja possível o retorno de sua vegetação à condição prÊ-existente. O objetivo deste estudo foi analisar a estrutura e composição de uma floresta em processo de restauração, implantada hå dezoito anos, em årea da empresa Fattoria Piave, no município de IgarapÊ-Açu, Parå, afim de observar o processo de sucessão florestal na região, estabelecendo diretrizes para dinamizar a recomposição da flora local. Foram avaliados indivíduos a partir de 5 cm de DAP em 100 delimitaçþes de 10 m x 10 m. Após a coleta dos dados em campo, foi avaliada a distribuição das espÊcies por família botânica, a distribuição diamÊtrica dos indivíduos e calculado o índice de valor de importância (IVI) das espÊcies. Com base no inventårio, foram encontrados 1323 indivíduos arbustivos-arbóreos com DAP ? 5 cm, distribuídos em 32 espÊcies e 20 famílias botânicas. A família Meliaceae foi, quantitativamente, a mais representativa com cinco espÊcies. A estrutura da floresta apresentou o padrão usual de florestas tropicais inequiâneas (J-invertido). As espÊcies Jacaranda copaia e Acacia mangium somaram mais de 50% do total de indivíduos encontrados na årea de restauração

    Anålise da estrutura e composição de uma floresta em processo de restauração no município de IgarapÊ-Açu, Parå.

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    Após fortes distúrbios, uma årea degradada perde os seus meios bióticos de regeneração, necessitando de forte intervenção antrópica para que seja possível o retorno de sua vegetação à condição prÊ-existente. O objetivo deste estudo foi analisar a estrutura e composição de uma floresta em processo de restauração, implantada hå dezoito anos, em årea da empresa Fattoria Piave, no município de IgarapÊ-Açu, Parå, afim de observar o processo de sucessão florestal na região, estabelecendo diretrizes para dinamizar a recomposição da flora local. Foram avaliados indivíduos a partir de 5 cm de DAP em 100 delimitaçþes de 10 m x 10 m. Após a coleta dos dados em campo, foi avaliada a distribuição das espÊcies por família botânica, a distribuição diamÊtrica dos indivíduos e calculado o índice de valor de importância (IVI) das espÊcies. Com base no inventårio, foram encontrados 1323 indivíduos arbustivos-arbóreos com DAP ? 5 cm, distribuídos em 32 espÊcies e 20 famílias botânicas. A família Meliaceae foi, quantitativamente, a mais representativa com cinco espÊcies. A estrutura da floresta apresentou o padrão usual de florestas tropicais inequiâneas (J-invertido). As espÊcies Jacaranda copaia e Acacia mangium somaram mais de 50% do total de indivíduos encontrados na årea de restauração

    Performance of the CMS Cathode Strip Chambers with Cosmic Rays

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    The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

    Performance and Operation of the CMS Electromagnetic Calorimeter

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    The operation and general performance of the CMS electromagnetic calorimeter using cosmic-ray muons are described. These muons were recorded after the closure of the CMS detector in late 2008. The calorimeter is made of lead tungstate crystals and the overall status of the 75848 channels corresponding to the barrel and endcap detectors is reported. The stability of crucial operational parameters, such as high voltage, temperature and electronic noise, is summarised and the performance of the light monitoring system is presented

    Enzyme replacement therapy with galsulfase in 34 children younger than five years of age with MPS VI

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    Background: Mucopolysaccharidosis type VI (MPS VI) is a progressive, chronic and multisystem lysosomal storage disease with a wide disease spectrum. Clinical and biochemical improvements have been reported for MPS VI patients on enzyme replacement therapy (ERT) with rhASB (recombinant human arylsulfatase B; galsulfase, Naglazyme (R), BioMarin Pharmaceutical Inc.), making early diagnosis and intervention imperative for optimal patient outcomes. Few studies have included children younger than five years of age. This report describes 34 MPS VI patients that started treatment with galsulfase before five years of age.Methods: Data from patients who initiated treatment at <5 years of age were collected from patients' medical records. Baseline and follow-up assessments of common symptoms that led to diagnosis and that were used to evaluate disease progression and treatment efficacy were evaluated.Results: A significant negative correlation was seen with treatment with ERT and urinary GAG levels. of those with baseline and follow-up growth data, 47% remained on their pre-treatment growth curve or moved to a higher percentile after treatment. of the 9 patients with baseline and follow-up sleep studies, 5 remained unaffected and 1 patient initially with mild sleep apnea showed improvement. Data regarding cardiac, ophthalmic, central nervous system, hearing, surgical interventions and development are also reported. No patient discontinued treatment due to an adverse event and all that were treatment-emergent resolved.Conclusions: the prescribed dosage of 1 mg/kg IV weekly with galsulfase ERT is shown to be safe and effective in slowing and/or improving certain aspects of the disease, although patients should be closely monitored for complications associated with the natural history of the disease, especially cardiac valve involvement and spinal cord compression. A long-term follow-up investigation of this group of children will provide further information on the benefits of early treatment as well as disease progression and treatment efficacy and safety in this young patient population. (C) 2013 Elsevier Inc. All rights reserved.BioMarin Pharmaceutical Inc.ShireGenzymeBioMarinFiocruz MS, Inst Nacl Saude Mulher Crianca & Adolescente Fern, Ctr Genet Med, BR-22250020 Rio de Janeiro, RJ, BrazilUniv Fed Bahia, Serv Genet Med, Salvador, BA, BrazilHosp Albert Sabin, Fortaleza, Ceara, BrazilUniv Fed Mato Grosso do Sul, Fac Med, Campo Grande, MS USAUniv SĂŁo Paulo, Inst Crianca, SĂŁo Paulo, BrazilHosp Barao de Lucena, Recife, PE, BrazilUniv Fed Parana, Hosp Clin, BR-80060000 Curitiba, Parana, BrazilCtr Reabilitacao Infantil, Natal, RN, BrazilHosp Univ Maranhao, Sao Luis, MA, BrazilUniversidade Federal de SĂŁo Paulo, Ctr Referencia Erros Inatos Metab, SĂŁo Paulo, SP, BrazilHosp SĂŁo Paulo, Enzyme Replacement Therapy Serv, Hosp & Maternidade Celso Pierro, SĂŁo Paulo, BrazilUniv Fed Rio Grande do Norte, HOSPED, Hosp Pediat Prof Heriberto Ferreira Bezerra, Natal, RN, BrazilUniv Fortaleza, Fortaleza, Ceara, BrazilUniv Fed Rio Grande do Norte, BR-59072970 Natal, RN, BrazilUniv Fed Triangulo Mineiro, Uberaba, MG, BrazilHosp Clin Acre, Rio Branco, AC, BrazilUniv Fed Espirito Santo, HUCAM, Vitoria, ES, BrazilUniversidade Federal de SĂŁo Paulo, Ctr Referencia Erros Inatos Metab, SĂŁo Paulo, SP, BrazilHosp SĂŁo Paulo, Enzyme Replacement Therapy Serv, Hosp & Maternidade Celso Pierro, SĂŁo Paulo, BrazilWeb of Scienc

    Calibration of the CMS Drift Tube Chambers and Measurement of the Drift Velocity with Cosmic Rays

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    Alignment of the CMS silicon tracker during commissioning with cosmic rays

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    The CMS silicon tracker, consisting of 1440 silicon pixel and 15 148 silicon strip detector modules, has been aligned using more than three million cosmic ray charged particles, with additional information from optical surveys. The positions of the modules were determined with respect to cosmic ray trajectories to an average precision of 3-4 microns RMS in the barrel and 3-14 microns RMS in the endcap in the most sensitive coordinate. The results have been validated by several studies, including laser beam cross-checks, track fit self-consistency, track residuals in overlapping module regions, and track parameter resolution, and are compared with predictions obtained from simulation. Correlated systematic effects have been investigated. The track parameter resolutions obtained with this alignment are close to the design performance

    Commissioning and performance of the CMS silicon strip tracker with cosmic ray muons

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    This is the Pre-print version of the Article. The official published version of the Paper can be accessed from the link below - Copyright @ 2010 IOPDuring autumn 2008, the Silicon Strip Tracker was operated with the full CMS experiment in a comprehensive test, in the presence of the 3.8 T magnetic field produced by the CMS superconducting solenoid. Cosmic ray muons were detected in the muon chambers and used to trigger the readout of all CMS sub-detectors. About 15 million events with a muon in the tracker were collected. The efficiency of hit and track reconstruction were measured to be higher than 99% and consistent with expectations from Monte Carlo simulation. This article details the commissioning and performance of the Silicon Strip Tracker with cosmic ray muons.This work is supported by FMSR (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); Academy of Sciences and NICPB (Estonia); Academy of Finland, ME, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLP-FAI (Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST and MAE (Russia); MSTDS (Serbia); MICINN and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK (Turkey); STFC (United Kingdom); DOE and NSF (USA)
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