16 research outputs found
Helium identification with LHCb
The identification of helium nuclei at LHCb is achieved using a method based on measurements of ionisation losses in the silicon sensors and timing measurements in the Outer Tracker drift tubes. The background from photon conversions is reduced using the RICH detectors and an isolation requirement. The method is developed using pp collision data at √(s) = 13 TeV recorded by the LHCb experiment in the years 2016 to 2018, corresponding to an integrated luminosity of 5.5 fb-1. A total of around 105 helium and antihelium candidates are identified with negligible background contamination. The helium identification efficiency is estimated to be approximately 50% with a corresponding background rejection rate of up to O(10^12). These results demonstrate the feasibility of a rich programme of measurements of QCD and astrophysics interest involving light nuclei
Momentum scale calibration of the LHCb spectrometer
For accurate determination of particle masses accurate knowledge of the momentum scale of the detectors is crucial. The procedure used to calibrate the momentum scale of the LHCb spectrometer is described and illustrated using the performance obtained with an integrated luminosity of 1.6 fb-1 collected during 2016 in pp running. The procedure uses large samples of J/ψ → μ + μ - and B+ → J/ψ K + decays and leads to a relative accuracy of 3 × 10-4 on the momentum scale
Curvature-bias corrections using a pseudomass method
Momentum measurements for very high momentum charged particles, such as muons from electroweak vector boson decays, are particularly susceptible to charge-dependent curvature biases that arise from misalignments of tracking detectors. Low momentum charged particles used in alignment procedures have limited sensitivity to coherent displacements of such detectors, and therefore are unable to fully constrain these misalignments to the precision necessary for studies of electroweak physics. Additional approaches are therefore required to understand and correct for these effects. In this paper the curvature biases present at the LHCb detector are studied using the pseudomass method in proton-proton collision data recorded at centre of mass energy √(s)=13 TeV during 2016, 2017 and 2018. The biases are determined using Z→μ + μ - decays in intervals defined by the data-taking period, magnet polarity and muon direction. Correcting for these biases, which are typically at the 10-4 GeV-1 level, improves the Z→μ + μ - mass resolution by roughly 18% and eliminates several pathological trends in the kinematic-dependence of the mean dimuon invariant mass
Approaches to diagnosis social and economic potential of regions as the basis for effective management strategies
The aim of article. The aim of article is development and justification of the directions of an effective strategy of regional development based on quantitative evaluation and analysis of the socio-economic potential of the region.
The results of the analysis. In the article the methods of quantitative evaluation and analysis of the socio-economic potential of the region (in terms of regional resources), resulting in a set that is still no unified system of regional development and general methods of combining these indicators into one integrated quantitative index. All this creates problems when assessing and managing the development of the region. Based on the concept of socio-economic potential of the region, proposed the evaluation of regional resources to carry out the following blocks: human resources, property potential social potential.
Summarizing the analysis of views of scientists on the possible assessment of the level of socio-economic potential of the region, we note that despite the constant improvement of definitions and study the factors that influence its components (human resources, property potential social potential) scorecard is imperfect and methodical approach to determine the integral index of socio-economic potential – incomplete or representative.
The value of the proposed approach is the ability to explore and comprehensively assess the current level of social and economic potential of the region at any given time. The proposed system of indicators to assess regional resources will solve the problem of lack of unity in the evaluation of selected indicators and provide an opportunity to determine the main direction of improvement of regional development based on the results. The main directions of effective strategy of regional development based on the results of quantitative assessment and analysis of the socio-economic potential of the region should increase national wealth by optimizing the use of resources in the region.
Conclusions and directions for further research. Given the common goal of social and economic development and the need to determine the direction of development of the region for the long term, the prospects for future research aimed at developing new approaches to the study of regional resources in terms of their ability to provide current and future needs of the population
Empirical therapy for vulvovaginitis in reproductive-aged women in routine clinical practice
Objective. To evaluate the efficiency of empirical therapy with tergynan in reproductive-aged women in routine clinical practice. Subjects and methods. The TERRA multicenter post-registration observational study enrolled 430 reproductive-aged patients diagnosed with acute vulvovaginitis. Based on their complaints, clinical symptoms, and objective examination, the patients received empirical therapy with the combination antimicrobial drug Tergynan as a single vaginal tablet once daily for 10 days. Gynecological examination, pH-metry, and bacterioscopic and bacteriological examinations of discharge (Femoflor-16) were performed, and the time course of changes in clinical symptoms evaluated. Results. There was less vaginal discharge, a complete disappearance of unpleasant odor, and a feeling of vaginal itching and burning (74.5 and 67.1%, respectively). There were increases in the detection rate of Lactobacillus spp. by 2 times with a dissemination level of 106-107 CFU/ml, in the suppression of obligate anaerobic representatives (associations of Gardnerella vaginalis + Prevotella bivia + Porphyromonas spp., as well as Eubacterium spp.) by 5 times, facultative anaerobic bacteria (Enterobacteriaceae and Streptococcus spp.) by 3 times, and yeast-like fungi of the genus Candida by 2 times. Conclusion. This investigation demonstrated the high clinical (96.5%) and microbiological (97.3%) efficiency of empirical therapy with tergynan in 430 reproductive-aged women with acute nonspecific vulvovaginitis. © 2020, Bionika Media Ltd. All rights reserved
The electrical birefringence of cellulose carbanilate solutions as a function of molecular weight
Influence of melting conditions of aluminum alloys on the properties and quality of castings obtained by lost foam casting
Non-immunogenic recombinant staphylokinase versus alteplase for patients with acute ischaemic stroke 4·5 h after symptom onset in Russia (FRIDA): a randomised, open label, multicentre, parallel-group, non-inferiority trial
Background: Non-immunogenic staphylokinase is modified recombinant staphylokinase with low immunogenicity, high thrombolytic activity, and selectivity to fibrin. We aimed to assess the safety and efficacy of a single intravenous bolus of non-immunogenic staphylokinase compared with alteplase in patients with acute ischaemic stroke within 4·5 h after symptom onset. Methods: We did a randomised, open-label, multicentre, parallel-group, non-inferiority trial in 18 clinical sites in Russia. We included patients aged 18 years and older with a diagnosis of acute ischaemic stroke (up to 25 points on the National Institutes of Health Stroke Scale). The study drug had to be administered within 4·5 h after the onset of symptoms. Patients were randomly assigned to receive either non-immunogenic staphylokinase (10 mg) or alteplase (0·9 mg/kg, maximum 90 mg), both administered intravenously. The randomisation sequence was created by an independent biostatistician using computer-generated random numbers. 84 blocks (block size of four) of opaque sealed envelopes were numbered sequentially from 1 to 336 and were opened in numerical order. Patients were unaware of their assigned treatment and were assessed by the study investigators who were also unaware of the treatment assignment on all trial days. Emergency department staff, who administered the assigned drug and opened the envelopes, were not masked to treatment. The primary efficacy endpoint was a favourable outcome, defined as a modified Rankin scale (mRS) score of 0–1 on day 90. The margin of non-inferiority was established as 16% for the difference in mRS score of 0–1 on day 90. Non-inferiority was tested using Welch's t-test for the primary outcome only. Endpoints were analysed in the per-protocol population, which comprised all randomly assigned patients who completed treatment without any protocol violations; this population was identical to the intention-to-treat population. This trial is completed and registered at ClinicalTrials.gov, NCT03151993. Findings: Of 385 patients recruited from March 18, 2017, to March 23, 2019, 336 (87%) were included in the trial. 168 (50%) patients were randomly assigned to receive non-immunogenic staphylokinase and 168 (50%) to receive alteplase. The median duration of follow-up was 89 days (IQR 89–89). 84 (50%) of 168 patients in the non-immunogenic staphylokinase group had a favourable outcome at day 90 compared with 68 (40%) of 168 patients in the alteplase group (odds ratio [OR] 1·47, 95% CI 0·93 to 2·32; p=0·10). The difference in the rate of favourable outcome at day 90 was 9·5% (95% CI –1·7 to 20·7) and the lower limit did not cross the margin of non-inferiority (pnon-inferiority <0·0001). Symptomatic intracranial haemorrhage occurred in five (3%) patients in the non-immunogenic staphylokinase group and in 13 (8%) patients in the alteplase group (p=0·087). On day 90, 17 (10%) patients in the non-immunogenic staphylokinase group and 24 (14%) patients in the alteplase group had died (p=0·32). 22 (13%) patients in the non-immunogenic staphylokinase group had serious adverse events, compared with 37 (22%) patients in the alteplase group (p=0·044). Interpretation: Non-immunogenic staphylokinase was non-inferior to alteplase for patients with acute ischaemic stroke. Mortality, symptomatic intracranial haemorrhage, and serious adverse events did not differ significantly between groups. Future studies are needed to continue to assess the safety and efficacy of non-immunogenic staphylokinase in patients with acute ischaemic stroke within the 4·5 h time window, and to assess the drug in patients with acute ischaemic stroke outside this time window with reperfusion CT or magnetic resonance angiography followed by thrombectomy if necessary. Funding: The Russian Academy of Sciences. © 2021 Elsevier Lt