75 research outputs found

    Multiple locus VNTR analysis highlights that geographical clustering and distribution of Dichelobacter nodosus, the causal agent of footrot in sheep, correlates with inter-country movements

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    Dichelobacter nodosus is a Gram-negative, anaerobic bacterium and the causal agent of footrot in sheep. Multiple locus variable number tandem repeat (VNTR) analysis (MLVA) is a portable technique that involves the identification and enumeration of polymorphic tandem repeats across the genome. The aims of this study were to develop an MLVA scheme for D. nodosus suitable for use as a molecular typing tool, and to apply it to a global collection of isolates. Seventy-seven isolates selected from regions with a long history of footrot (GB, Australia) and regions where footrot has recently been reported (India, Scandinavia), were characterised. From an initial 61 potential VNTR regions, four loci were identified as usable and in combination had the attributes required of a typing method for use in bacterial epidemiology: high discriminatory power (D > 0.95), typeability and reproducibility. Results from the analysis indicate that D. nodosus appears to have evolved via recombinational exchanges and clonal diversification. This has resulted in some clonal complexes that contain isolates from multiple countries and continents; and others that contain isolates from a single geographic location (country or region). The distribution of alleles between countries matches historical accounts of sheep movements, suggesting that the MLVA technique is sufficiently specific and sensitive for an epidemiological investigation of the global distribution of D. nodosus

    The data acquisition system of the CHORUS experiment

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    In the years 1994--1998 the CHORUS Collaboration has recorded data in the CERN WA95 experiment. Here we describe the data acquisition system that has been used, featuring concurrent hierarchical state machines, a remote operating system, a buffer manager, a dispatcher, a control panel and a supervisor

    Experimental search for muonic photons

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    We report new limits on the production of muonic photons in the CERN neutrino beam. The results are based on the analysis of neutrino production of dimuons in the CHARM II detector. A 90%90\% CL limit on the coupling constant of muonic photons, αΌ/α<(1.5Ă·3.2)×10−6\alpha_{\mu} / \alpha < (1.5 \div 3.2) \times10^{-6} is derived for a muon neutrino mass in the range mΜΌ=(10−20Ă·105)m_{\nu_{\mu}} = (10^{-20} \div 10^5) eV. This improves the limit obtained from a precision measurement of the anomalous magnetic moment of the muon (g−2)ÎŒ(g-2)_\mu by a factor from 8 to 4

    Leading-order QCD Analysis of Neutrino-Induced Dimuon Events

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    The results of a leading-order QCD analysis of neutrino-induced charm production are presented. They are based on a sample of 4111 \numu- and 871 \anumu-induced opposite-sign dimuon events with EÎŒ1,EÎŒ2>6 GeVE_{\mu 1},E_{\mu 2} > 6~{\rm GeV}, 355.5 GeV235 5.5\,{\rm GeV^2}, observed in the CHARM~II detector exposed to the CERN wideband neutrino and antineutrino beams. The analysis yields the value of \linebreak the charm quark mass mc=1.79±0.38 GeV/c2m_c=1.79\pm0.38\,{\rm GeV}/c^2 and the Cabibbo--Kobayashi--Maskawa matrix element ∣Vcd∣=0.219±0.016|V_{cd}|=0.219\pm0.016. The strange quark content of the nucleon is found to be suppressed with respect to non-strange sea quarks by a factor Îș=0.39±0.09\kappa =0.39\pm0.09

    Observation of weak neutral current neutrino production of J/ψJ/\psi

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    Observation of \jpsi production by neutrinos in the calorimeter of the CHORUS detector exposed to the CERN SPS wide-band \numu beam is reported. A spectrum-averaged cross-section σJ/ψ\sigma^{\mathrm{J/\psi}} = (6.3 ±\pm 3.0) ×10−41 cm2\times \mathrm{10^{-41}~cm^{2}} is obtained for 20 GeV ≀EΜ≀\leq E_{\nu} \leq 200 GeV. The data are compared with the theoretical model based on the QCD Z-gluon fusion mechanism

    The CHORUS neutrino oscillation search experiment

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    The CHORUS experiment has successfully finished run I (320~000 recorded \numu\ CC in 94/95) and performed half of run II (225~000 \numu\ CC in 96). The analysis chain was exercised on a small data sample for the muonic \tdecay\ search using for the first time fully automatic emulsion scanning. This pilot analysis, resulting in a limit \sintth \leq 3 \cdot 10^{-2}, confirms that the CHORUS proposal sensitivity (\sintth \leq 3 \cdot 10^{-4}) is within reach in two years

    A united statement of the global chiropractic research community against the pseudoscientific claim that chiropractic care boosts immunity.

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    BACKGROUND: In the midst of the coronavirus pandemic, the International Chiropractors Association (ICA) posted reports claiming that chiropractic care can impact the immune system. These claims clash with recommendations from the World Health Organization and World Federation of Chiropractic. We discuss the scientific validity of the claims made in these ICA reports. MAIN BODY: We reviewed the two reports posted by the ICA on their website on March 20 and March 28, 2020. We explored the method used to develop the claim that chiropractic adjustments impact the immune system and discuss the scientific merit of that claim. We provide a response to the ICA reports and explain why this claim lacks scientific credibility and is dangerous to the public. More than 150 researchers from 11 countries reviewed and endorsed our response. CONCLUSION: In their reports, the ICA provided no valid clinical scientific evidence that chiropractic care can impact the immune system. We call on regulatory authorities and professional leaders to take robust political and regulatory action against those claiming that chiropractic adjustments have a clinical impact on the immune system
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