4,206 research outputs found

    Modélisation des écoulements issus de la fonte du glacier 15 de l'Antizana en Equateur

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    A Novel Scheme to Search for Fractional Charge Particles in Low Energy Accelerator Experiments

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    In the Standard Model of particle physics, the quarks and anti-quarks have fractional charge equal to ±1/3\pm1/3 or ±2/3\pm2/3 of the electron's charge. There has been a large number of experiments searching for fractional charge, isolatable, elementary particles using a variety of methods, including e+ee^+e^- collisions using dE/dx ionization energy loss measurements, but no evidence has been found to confirm existence of free fractional charge particles, which leads to the quark confinement theory. In this paper, a proposal to search for this kind particles is presented, which is based on the conservation law of four-momentum. Thanks to the CLEOc and BESIII detectors' large coverage, good particle identification, precision measurements of tracks' momenta and their large recorded data samples, these features make the scheme feasible in practice. The advantage of the scheme is independent of any theoretical models and sensitive for a small fraction of the quarks transitioning to the unconfinement phase from the confinement phase.Comment: 9 page

    First determination of the CPCP content of Dπ+ππ+πD \to \pi^+\pi^-\pi^+\pi^- and updated determination of the CPCP contents of Dπ+ππ0D \to \pi^+\pi^-\pi^0 and DK+Kπ0D \to K^+K^-\pi^0

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    Quantum-correlated ψ(3770)DDˉ\psi(3770) \to D\bar{D} decays collected by the CLEO-c experiment are used to perform a first measurement of F+4πF_+^{4\pi}, the fractional CPCP-even content of the self-conjugate decay Dπ+ππ+πD \to \pi^+\pi^-\pi^+\pi^-, obtaining a value of 0.737±0.0280.737 \pm 0.028. An important input to the measurement comes from the use of DKS0π+πD \to K^0_{\rm S}\pi^+\pi^- and DKL0π+πD \to K^0_{\rm L}\pi^+\pi^- decays to tag the signal mode. This same technique is applied to the channels Dπ+ππ0D \to\pi^+\pi^-\pi^0 and DK+Kπ0D \to K^+K^-\pi^0, yielding F+πππ0=1.014±0.045±0.022F_+^{\pi\pi\pi^0} = 1.014 \pm 0.045 \pm 0.022 and F+KKπ0=0.734±0.106±0.054F_+^{KK\pi^0} = 0.734 \pm 0.106 \pm 0.054, where the first uncertainty is statistical and the second systematic. These measurements are consistent with those of an earlier analysis, based on CPCP-eigenstate tags, and can be combined to give values of F+πππ0=0.973±0.017F_+^{\pi\pi\pi^0} = 0.973 \pm 0.017 and F+KKπ0=0.732±0.055F_+^{KK\pi^0} = 0.732 \pm 0.055. The results will enable the three modes to be included in a model-independent manner in measurements of the unitarity triangle angle γ\gamma using BDKB^\mp \to DK^\mp decays, and in time-dependent studies of CPCP violation and mixing in the DDˉD\bar{D} system.Comment: Minor revisions following journal acceptanc

    Joint density-functional theory for electronic structure of solvated systems

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    We introduce a new form of density functional theory for the {\em ab initio} description of electronic systems in contact with a molecular liquid environment. This theory rigorously joins an electron density-functional for the electrons of a solute with a classical density-functional theory for the liquid into a single variational principle for the free energy of the combined system. A simple approximate functional predicts, without any fitting of parameters to solvation data, solvation energies as well as state-of-the-art quantum-chemical cavity approaches, which require such fitting.Comment: Fixed typos and minor updates to tex

    Exclusive Lambda_b -> Lambda l^+ l^- decay in two Higgs doublet model

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    Rare Lambda_b -> Lambda l^+ l^- decay is investigated in framework of general two Higgs doublet model, in which a new source of CP violation exists (model III). The polarization parameter, CP asymmetry and decay width are calculated. It is shown that CP asymmetry is a very sensitive tool for establishing model III.Comment: 16 pages, 3 figures, LaTeX formatte

    Use of MenACWY-CRM vaccine in children aged 2 through 23 months at increased risk for meningococcal disease: recommendations of the Advisory Committee on Immunization Practices, 2013

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    During its October 2013 meeting, the Advisory Committee on Immunization Practices (ACIP) recommended use of a third meningococcal conjugate vaccine, MenACWY-CRM (Menveo, Novartis), as an additional option for vaccinating infants aged 2 through 23 months at increased risk for meningococcal disease. MenACWY-CRM is the first quadrivalent meningococcal conjugate vaccine licensed for use in children aged 2 through 8 months. MenACWY-D (Menactra, Sanofi Pasteur) is recommended for use in children aged 9 through 23 months who are at increased risk for meningococcal disease, and Hib-MenCY-TT (MenHibrix, GlaxoSmithKline) is recommended for use in children aged 6 weeks through 18 months at increased risk. This report summarizes information on MenACWY-CRM administration in infants and provides recommendations for vaccine use in infants aged 2 through 23 months who are at increased risk for meningococcal disease. Because the burden of meningococcal disease in infants is low in the United States and the majority of cases that do occur are caused by serogroup B, which is not included in any vaccine licensed in the United States, only those infants who are at increased risk for meningococcal disease are recommended to receive a meningococcal vaccine

    Sexual exploitation in children: Nature, prevalence and distinguishing characteristics reported in young adulthood

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    The aim of this study was to explore the nature and extent of sexual exploitation in a university student sample, whilst being clear that sexual exploitation is sexual abuse. Overall, 47% of participants (96 out of 204) reported having been approached by an adult in a sexual manner when they were under the age of 16. The study predicted that a number of individual characteristics would increase a young person’s vulnerability for sexual exploitation. These included low self-esteem, external locus of control, social loneliness and insecure attachment. Results indicated lower levels of self-esteem among those who had been approached sexually, although it is not clear in terms of causality. There were no differences in scores for locus of control or loneliness. Relationship anxiety was significantly linked with children having engaged in sexual behaviours with an adult. The implications of these findings are discussed in terms of emerging individual characteristics relating to a risk of sexual exploitation

    The remittances behaviour of the second generation in Europe: altruism or self-interest?

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    Whereas most research on remittances focuses on first-generation migrants, the aim of this paper is to investigate the remitting behaviour of the host country-born children of migrants - the second generation - in various European cities. Some important studies found that migrant transnationalism is not only a phenomenon for the first generation, but also apply to the second and higher generations, through, among other things, family visits, elder care, and remittances. At the same time, the maintenance of a strong ethnic identity in the ‘host’ society does not necessarily mean that second-generation migrants have strong transnational ties to their ‘home’ country. The data used in this paper is from “The Integration of the European Second Generation” (TIES) project. The survey collected information on approximately 6,250 individuals aged 18-35 with at least one migrant parent from Morocco, Turkey or former Yugoslavia, in 15 European cities, regrouped in 8 ‘countries’. For the purpose of this paper, only analyses for Austria (Linz and Vienna); Switzerland (Basle and Zurich); Germany (Berlin and Frankfurt); France (Paris and Strasbourg); the Netherlands (Amsterdam and Rotterdam); Spain (Barcelona and Madrid); and Sweden (Stockholm) will be presented.

    Temporal trends in the incidence, treatment patterns, and outcomes of coronary artery disease and peripheral artery disease in the UK, 2006–2015

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    Aims Most reports estimating national incidence rates of coronary (CAD) and peripheral arterial disease (PAD) have focused on stable outpatients or acute or elective hospital admissions, but not on the overall burden of disease. In this study, we report the changing trends in the population-level incidence of CAD and PAD, respectively from 2006 to 2015, statin utilization for secondary prevention and survival outcomes using multiple nationally representative data sources from the UK (primary care encounters, hospital admissions, and procedure-level data). Methods and results A nationally representative study of linked primary and secondary care electronic health records of 4.6 million individuals from the UK. We calculated crude and standardized annual incidence rates separately for CAD and PAD. Statin use for secondary prevention, trends in annual major vascular event rates, and mortality between 2006 and 2015, were estimated for CAD and PAD, respectively. We identified 160 376 and 70 753 patients with incident CAD and PAD, respectively. The age- and sex-standardized incidence of CAD was similar in 2006 (443 per 100 000 person-years) and 2015 [436 per 100 000 person-years; adjusted incidence rate ratio (IRR) 0.98, 95% confidence interval (CI) 0.96–1.00]. In contrast, there was a 15% decline in the standardized incidence of PAD (236 per 100 000 person-years in 2006 to 202 per 100 000 person-years in 2015; adjusted IRR 0.85, 95% CI 0.82–0.88). The proportion of incident CAD and PAD patients prescribed long-term statins, was only 66% and 55%, respectively and was less common amongst women, patients aged >70 years, with heart failure, chronic lung disease, or depression. Cardiovascular mortality declined by 43% for incident CAD (adjusted IRR 0.57, 95% CI 0.50–0.64) between 2006 and 2015 but did not decline for incident PAD (adjusted IRR 0.84, 95% CI 0.70–1.00). Conclusion and relevance In the UK, the standardized incidence of CAD appears stable but mortality rates are falling, whereas the standardized incidence of PAD is falling but mortality rates are not
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