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We report the direct observation of muon neutrino interactions with the SND@LHC detector at the Large Hadron Collider. A dataset of proton-proton collisions at sqrt[s]=13.6 TeV collected by SND@LHC in 2022 is used, corresponding to an integrated luminosity of 36.8 fb^{-1}. The search is based on information from the active electronic components of the SND@LHC detector, which covers the pseudorapidity region of 7.2<η<8.4, inaccessible to the other experiments at the collider. Muon neutrino candidates are identified through their charged-current interaction topology, with a track propagating through the entire length of the muon detector. After selection cuts, 8 ν_{µ} interaction candidate events remain with an estimated background of 0.086 events, yielding a significance of about 7 standard deviations for the observed ν_{µ} signal.
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The OPERA experiment was designed to discover the vτ appearance in a vµ beam, due to neutrino oscillations. The detector, located in the underground Gran Sasso Laboratory, consisted of a nuclear photographic emulsion/lead target with a mass of about 1.25 kt, complemented by electronic detectors. It was exposed from 2008 to 2012 to the CNGS beam: an almost pure vµ beam with a baseline of 730 km, collecting a total of 1.8·1020 protons on target. The OPERA Collaboration eventually assessed the discovery of vµâvτ oscillations with a statistical significance of 6.1 σ by observing ten vτ CC interaction candidates. These events have been published on the Open Data Portal at CERN. This paper provides a detailed description of the vτ data sample to make it usable by the whole community.
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OBJECTIVE: To analyze hospital and long-term results of stenting of the V1 segment of the vertebral artery (VA) in the first hours after acute cerebral hemopoiesis/transient ischemic attack (stroke/TIA) in the vertebrobasilar territory (VT). MATERIAL AND METHODS: The current retrospective study from 2012 to 2019 included 169 patients with hemodynamically significant stenosis of the V1 segment of the VA, who underwent emergency stenting in the first hours after the onset of stroke. The mean time between the development of stroke and correction was 368.5±129.8 minutes. The average time between admission to the medical institution and submission to the X-ray operating room was 89.2±10.7 minutes. VA stenting was performed through the transfemoral approach. In 118 cases (69.8%) a drug eluting stent was implanted, in 51 (30.2%) a bare metal stent was implanted. 90% of VA segment V1 stenosis was diagnosed in 48 patients before the onset of stroke. Of these, 33 received conservative therapy for vertebrobasilar insufficiency (VBI) for 2.5±1.0 months in anticipation of regression of the disease. The remaining 15 did not have VBI symptoms and did not need active drug treatment. Ultimately, within this sample, the time interval between the visualization of stenosis and the onset of stroke was 3.0±1.0 months. In 17 patients, stroke/TIA in VT became recurrent. The period between two neurological events was 1.5±0.5 months. Nine patients did not wait for the planned intervention due to the development of an adverse neurological event before the appointed date of hospitalization. The other 8 did not appear for the interventional correction on time due to subjective reasons and were again admitted to the medical facility on an urgent basis. RESULTS: During the hospital follow-up period, no adverse cardiovascular events were recorded. When assessing the dynamics in the neurological status, there was a significant regression of the deficit by the time of discharge from the hospital. In the long-term follow-up period (38.2±20.4 months), a fatal outcome was recorded in 2.4% of cases (n=4). Non-fatal myocardial infaction was diagnosed in 5 patients (2.9%). Restenosis of the stent in the VA was visualized in 56 patients (33.1%). In 17 cases, it became symptomatic (10.0%). All patients underwent repeated stenting with a successful result of the procedure. CONCLUSION: Emergency stenting of hemodynamically significant stenosis of the V1 segment of the VA in the acute period of stroke in VT is a safe and effective method of revascularization characterized by the absence of adverse cardiovascular events at the hospital stage of observation.
Assuntos
Isquemia Encefálica , Stents Farmacológicos , AVC Isquêmico , Acidente Vascular Cerebral , Insuficiência Vertebrobasilar , Isquemia Encefálica/etiologia , Seguimentos , Humanos , Estudos Retrospectivos , Stents , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento , Insuficiência Vertebrobasilar/diagnóstico por imagem , Insuficiência Vertebrobasilar/cirurgiaRESUMO
The OPERA experiment was designed to study ν_{µ}âν_{τ} oscillations in the appearance mode in the CERN to Gran Sasso Neutrino beam (CNGS). In this Letter, we report the final analysis of the full data sample collected between 2008 and 2012, corresponding to 17.97×10^{19} protons on target. Selection criteria looser than in previous analyses have produced ten ν_{τ} candidate events, thus reducing the statistical uncertainty in the measurement of the oscillation parameters and of ν_{τ} properties. A multivariate approach for event identification has been applied to the candidate events and the discovery of ν_{τ} appearance is confirmed with an improved significance level of 6.1σ. |Δm_{32}^{2}| has been measured, in appearance mode, with an accuracy of 20%. The measurement of the ν_{τ} charged-current cross section, for the first time with a negligible contamination from ν[over ¯]_{τ}, and the first direct evidence for the ν_{τ} lepton number are also reported.
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AIM: to assess effect of thromboendarterectomy from pulmonary artery branches on clinical functional state of patients with chronic thromboembolic pulmonary hypertension (CTEPH) in dependence on degree of pulmonary hypertension and disease duration. MATERIAL: Patients (n=152) were divided into 3 groups: (1) with systolic pulmonary artery pressure (SPAP) less or equal 50 mm Hg (n=20), (2) with SPAP>50- less or equal 80mm Hg (n=46), (3) with SPAP >80mm Hg (n=86). METHODS: Examination included registration of dynamics of general clinical state and character of complaints, six-minute walk test, transthoracic echocardiography with measurement of SPAP and right ventricular ejection fraction, pulmonary perfusion scintigraphy with calculation of index of perfusion deficit. RESULTS AND CONCLUSION: Pulmonary thromboendarterectomy from pulmonary artery branches was associated with stable improvement of clinical functional state of patients with CTEPH and regression of symptoms irrespective of preoperative level of pulmonary hypertension.