4,370 research outputs found

    Z0 Boson Measurement with the ALICE Central Barrel in pp collisions at 14 TeV

    Get PDF
    The possibility to detect the Z0 in the ALICE central barrel is studied via the electronic decay channel Z0->e+e-. The signal and the background are simulated with the leading order event generator PYTHIA 6. The total cross-sections are taken from NLO calculations. Based on test beam data, the electron identification performance of the Transition Radiation Detector is extrapolated to high momenta. The expected yields for minimum-bias pp collisions at 14 TeV are presented. An isolation cut on the single electron, together with a minimum transverse momentum cut, allows to obtain a clear signal. The expected background is of the order of 1 % with the main contribution coming from misidentified pions from jets.Comment: 4 pages, 3 figures, QM2008 proceeding

    Direct determination of Al and Pb in waste printed circuit boards (PCB) by laser-induced breakdown spectroscopy (LIBS): Evaluation of calibration strategies and economic - environmental questions

    Get PDF
    Matrix-matching calibration (MMC), two-point calibration transfer (TP CT), one-point and multi-line calibration (OP MLC), single-sample calibration (SSC) and calibration free (CF) were evaluated in order to overcome matrix effects in laser-induced breakdown spectroscopy (LIBS). These calibration strategies were evaluated for direct determination of Al and Pb in waste printed circuit boards (PCB) using direct solids analysis by LIBS. Each strategy has limitations and advantages of its implementation, for the correction of matrix effects, so that it allows elementary determination with adequate accuracy. The MMC and CF proved to be excellent calibration strategies for the determination of strategic (Al) and toxic (Pb) elements by LIBS, with good recoveries (ranging from 80–120%) and low relative standard deviation (RSD%) values. A detailed discussion of the advantages and limitations of each of these five calibration strategies evaluated for LIBS is presented in this study. Lead concentrations in waste PCB samples are 5–12 times higher than established by Directive 2011/65/EU, and the samples analyzed contain between 3 and 55 g kg-1 Al, being an interesting economic and recycling source for this metal

    Heavy-flavour production in Pb-Pb collisions at the LHC, measured with the ALICE detector

    Full text link
    We present the first results from the ALICE experiment on the nuclear modification factors for heavy-flavour hadron production in Pb-Pb collisions at sqrt{s_NN}=2.76 TeV. Using proton-proton and lead-lead collision samples at sqrt{s}=7 TeV and sqrt{s_NN}=2.76 TeV, respectively, nuclear modification factors R_AA(pt) were measured for D mesons at central rapidity (via displaced decay vertex reconstruction), and for electrons and muons, at central and forward rapidity, respectively.Comment: 8 pages, 5 figures, plenary talk at Quark Matter 2011, Annecy, Franc

    D meson nuclear modification factors in Pb-Pb collisions at {\surd}sNN = 2.76 TeV, measured with the ALICE detector

    Full text link
    The ALICE experiment has measured the D meson production in pp and Pb-Pb collisions at the LHC at {\surd}s = 7 and 2.76 TeV and {\surd}sNN = 2.76 TeV respectively, via the exclusive reconstruction of hadronic decay channels. The analyses of the D0{\to}K-pi+ and D+{\to}K-pi+pi+ channels will be described and the preliminary results for the D0 and D+ nuclear modification factor will be presented.Comment: Proceedings of Quark Matter 2011 conference. 4 pages, 4 figures. The slides of the talk can be found at the link: http://indico.cern.ch/materialDisplay.py?contribId=591&sessionId=53&materialId=slides&confId=3024

    Beneficial effects of manually assisted chiropractic adjusting instrument in a rabbit model of osteoarthritis.

    Get PDF
    Osteoarthritis (OA) is a degenerative disease characterized by injury of all joint tissues. Our previous study showed that in experimental osteoporosis, chiropractic manipulation (CM) exerts protective effects on bone. We here assessed whether CM might ameliorate OA by improving subchondral bone sclerosis, cartilage integrity and synovitis. Male New-Zealand rabbits underwent knee surgery to induce OA by anterior cruciate ligament injury. CM was performed using the chiropractic instrument ActivatorV 3 times/week for 8 weeks as follows: force 2 setting was applied to the tibial tubercle of the rabbit right hind limb (TM-OA), whereas the corresponding left hind limb received a false manipulation (FM-OA) consisting of ActivatorV firing in the air and slightly touching the tibial tubercle. After sacrifice, subchondral bone integrity was assessed in the tibiae by microCT and histology. Cartilage damage and synovitis were estimated by Mankin's and Krenn's scores, respectively, and histological techniques. Bone mineral density and content in both cortical and trabecular compartments of subchondral bone decreased in OA rabbits compared to controls, but partially reversed in the TM-OA group. Trabecular bone parameters in the latter group also showed a significant improvement compared to FM-OA group. Moreover RANKL, OPG, ALP and TRAP protein expression in subchondral bone significantly decreased in TM-OA rabbits with respect to FM-OA group. CM was associated with lower Mankin's and Krenn's scores and macrophage infiltrate together with a decreased protein expression of pro-inflammatory, fibrotic and angiogenic factors, in TM-OA rabbits with respect to FM-OA. Our results suggest that CM may mitigate OA progression by improving subchondral bone as well as cartilage and synovial membrane status.AODM was supported by grants from the Spanish Chiropractic Association (AEQ). AM was supported by grants from Spanish Ministry of Economy and Competitiveness and Carlos III Institute of Health (CP15/00053 and PI16/00991). We thank Dr. Carlos Guillén-Viejo (School of Pharmacy, Universidad Complutense de Madrid) for his help in advising in molecular biology methods. The authors are also grateful to Mark S. Davis for his assistance with editing and proofreading the article.S

    Heavy-flavour and quarkonium production in the LHC era: from proton-proton to heavy-ion collisions

    Get PDF
    This report reviews the study of open heavy-flavour and quarkonium production in high-energy hadronic collisions, as tools to investigate fundamental aspects of Quantum Chromodynamics, from the proton and nucleus structure at high energy to deconfinement and the properties of the Quark-Gluon Plasma. Emphasis is given to the lessons learnt from LHC Run 1 results, which are reviewed in a global picture with the results from SPS and RHIC at lower energies, as well as to the questions to be addressed in the future. The report covers heavy flavour and quarkonium production in proton-proton, proton-nucleus and nucleus-nucleus collisions. This includes discussion of the effects of hot and cold strongly interacting matter, quarkonium photo-production in nucleus-nucleus collisions and perspectives on the study of heavy flavour and quarkonium with upgrades of existing experiments and new experiments. The report results from the activity of the SaporeGravis network of the I3 Hadron Physics programme of the European Union 7th Framework Programme

    Efectos de la supresión del riego durante la postcosecha de nectarinos extra-tempranos en la acumulación de reservas nutricionales, producción y calidad del fruto. Póster

    Get PDF
    En nectarinos extra-tempranos cultivados en condiciones mediterráneas, se evaluó la idoneidad del largo periodo de postcosecha (mayo-octubre) para desarrollar estrategias de riego deficitario controlado. Para ello, se establecieron 4 tratamientos de riego: (i) Control (T‐CTL): regado al 100% ETc durante todo el año; (ii) Estrés 1 (T‐E1): supresión del riego en la postcosecha temprana (junio y julio); (iii) Estrés 2 (T‐E2): supresión del riego en la postcosecha tardía (agosto y septiembre), y iv) Estrés 3 (T‐E3): supresión del riego durante todo el período postcosecha (junio‐septiembre). Salvo en las fases de estrés, todos los tratamientos recibieron idénticas dosis de riego que T‐CTL. La producción total y el número de frutos por árbol fue mayor en T-CTL y T-E1, que en el resto de tratamientos de estrés. Además, el tratamiento T-E2 registró el mayor porcentaje de frutos agrietados. El análisis de reservas en raíz mostró valores significativamente más altos de arginina y fósforo en los árboles del tratamiento T‐E1 seguido de T‐CTL. No se observaron diferencias significativas entre tratamientos en los parámetros de calidad físico-química estudiados. Estos resultados sugieren que el periodo de postcosecha tardía (agosto‐septiembre), es más sensible que el de postcosecha temprana (junio-julio) al déficit hídrico severo, pues disminuye la acumulación de reservas nutricionales, afectando al rendimiento del cultivo

    Physics of the Muon Spectrometer of the ALICE Experiment

    Full text link
    The main goal of the Muon spectrometer of the ALICE experiment at LHC is the measurement of heavy quark production in p+p, p+A and A+A collisions at LHC energies, via the muonic channel. Physics motivations and expected performances have been presented in this talk.Comment: 10 pages and 4 figures. Talk presented in the ICPAQGP Conference, February 8-12, 2005, Salt Lake City, Kolkata, India. Web page of the conference : http://www.veccal.ernet.in/~icpaqgp
    corecore