53 research outputs found

    Right-handed Neutrinos in Low-Energy Neutrino-Electron Scattering

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    In this paper a scenario admitting the participation of the exotic scalar coupling of the right-handed neutrinos in addition to the standard vector and axial couplings of the left-handed neutrinos in the weak interactions is considered. The research is based on the low-energy (νμe−)(\nu_{\mu} e^{-}) and (νee−)(\nu_{e} e^{-}) scattering processes. The main goal is to show how the presence of the right-handed neutrinos in the above processes changes the laboratory differential cross section in relation to the Standard Model prediction. Both processes are studied at the level of the four-fermion point interaction. Neutrinos are assumed to be polarized Dirac fermions and to be massive. In the laboratory differential cross section, the new interference term between the standard vector coupling of the left-handed neutrinos and exotic scalar coupling of the right-handed neutrinos appears which does not vanish in the limit of massless neutrino. This additional contribution, including information about the transverse components of neutrino polarization, generates the azimuthal asymmetry in the angular distribution of the recoil electrons. This regularity would be a signature of the participation of the right-handed neutrinos in the neutrino-electron scattering. The future low-energy high-precision neutrino-electron scattering experiments using the strong and polarized artificial neutrino source would allow to search for the exotic effects coming from the R-handed neutrinos.Comment: REVTeX, 9 pages, 5 eps figures; published in Phys. Lett. B 555, 215-226 (2003

    Anticoagulant selection in relation to the SAMe-TT2R2 score in patients with atrial fibrillation. the GLORIA-AF registry

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    Aim: The SAMe-TT2R2 score helps identify patients with atrial fibrillation (AF) likely to have poor anticoagulation control during anticoagulation with vitamin K antagonists (VKA) and those with scores >2 might be better managed with a target-specific oral anticoagulant (NOAC). We hypothesized that in clinical practice, VKAs may be prescribed less frequently to patients with AF and SAMe-TT2R2 scores >2 than to patients with lower scores. Methods and results: We analyzed the Phase III dataset of the Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation (GLORIA-AF), a large, global, prospective global registry of patients with newly diagnosed AF and ≥1 stroke risk factor. We compared baseline clinical characteristics and antithrombotic prescriptions to determine the probability of the VKA prescription among anticoagulated patients with the baseline SAMe-TT2R2 score >2 and ≤ 2. Among 17,465 anticoagulated patients with AF, 4,828 (27.6%) patients were prescribed VKA and 12,637 (72.4%) patients an NOAC: 11,884 (68.0%) patients had SAMe-TT2R2 scores 0-2 and 5,581 (32.0%) patients had scores >2. The proportion of patients prescribed VKA was 28.0% among patients with SAMe-TT2R2 scores >2 and 27.5% in those with scores ≤2. Conclusions: The lack of a clear association between the SAMe-TT2R2 score and anticoagulant selection may be attributed to the relative efficacy and safety profiles between NOACs and VKAs as well as to the absence of trial evidence that an SAMe-TT2R2-guided strategy for the selection of the type of anticoagulation in NVAF patients has an impact on clinical outcomes of efficacy and safety. The latter hypothesis is currently being tested in a randomized controlled trial. Clinical trial registration: URL: https://www.clinicaltrials.gov//Unique identifier: NCT01937377, NCT01468701, and NCT01671007
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