11 research outputs found
The calculation technique for accelerating channel of the structure with the space-uniform RFQ focusing
Calculations were carried out for the initial part of the heavy ion accelerator with the large mass-to-charge ratio (a/q = 46). The process of calculation is divided in four stages. At the first stage the average aperture radius and the field strength are determined according to the initial data. At the second stage the optimization of the accelerating tract is performed. To the purpose, the structure is divided in 6 sections: a funnel (a cone), a bunch former, a pre-buncher, an adiabatic buncher, a booster, an accelerating section. At the third stage the obtained data are re-calculated in the values of the modulation depth and lengths of the accelerating periods with taking into account the real fields. At the fourth stage the beam parameters at the accelerator output are determined for the tract built with taking into account the space charge forces and the input beam parameters
Features of formation and the structure, composition, and properties of electrospark coatings on the ZhS6U nickel alloy with the use of the KhTN-61 SHS-Ts alloy
The study of agronomical traits determining the productivity of the Triticum aestivum/Triticum timopheevii introgression lines with resistance to fungal diseases
Geological characterization of the three high-priority landing sites for the Luna-Glob mission
Mineralogy and Formation Conditions of Novoshirokinsky Base Metal–Gold Deposit, Eastern Transbaikal Region, Russia
Clinical risk factors of adverse outcomes among women with COVID-19 in the pregnancy and postpartum period: A sequential, prospective meta-analysis.
This sequential, prospective meta-analysis (sPMA) sought to identify risk factors among pregnant and postpartum women with COVID-19 for adverse outcomes related to: disease severity, maternal morbidities, neonatal mortality and morbidity, adverse birth outcomes.
We prospectively invited study investigators to join the sPMA via professional research networks beginning in March 2020.
Eligible studies included those recruiting at least 25 consecutive cases of COVID-19 in pregnancy within a defined catchment area.
We included individual patient data from 21 participating studies. Data quality was assessed, and harmonized variables for risk factors and outcomes were constructed. Duplicate cases were removed. Pooled estimates for the absolute and relative risk of adverse outcomes comparing those with and without each risk factor were generated using a two-stage meta-analysis.
We collected data from 33 countries and territories, including 21,977 cases of SARS-CoV-2 infection in pregnancy or postpartum. We found that women with comorbidities (pre-existing diabetes, hypertension, cardiovascular disease) versus those without were at higher risk for COVID-19 severity and pregnancy health outcomes (fetal death, preterm birth, low birthweight). Participants with COVID-19 and HIV were 1.74 times (95% CI: 1.12, 2.71) more likely to be admitted to the ICU. Pregnant women who were underweight before pregnancy were at higher risk of ICU admission (RR 5.53, 95% CI: 2.27, 13.44), ventilation (RR 9.36, 95% CI: 3.87, 22.63), and pregnancy-related death (RR 14.10, 95% CI: 2.83, 70.36). Pre-pregnancy obesity was also a risk factor for severe COVID-19 outcomes including ICU admission (RR 1.81, 95% CI: 1.26,2.60), ventilation (RR 2.05, 95% CI: 1.20,3.51), any critical care (RR 1.89, 95% CI: 1.28,2.77), and pneumonia (RR 1.66, 95% CI: 1.18,2.33). Anemic pregnant women with COVID-19 also had increased risk of ICU admission (RR 1.63, 95% CI: 1.25, 2.11) and death (RR 2.36, 95% CI: 1.15, 4.81).
We found that pregnant women with comorbidities including diabetes, hypertension, and cardiovascular disease were at increased risk for severe COVID-19-related outcomes, maternal morbidities, and adverse birth outcomes. We also identified several less commonly-known risk factors, including HIV infection, pre-pregnancy underweight, and anemia. Although pregnant women are already considered a high-risk population, special priority for prevention and treatment should be given to pregnant women with these additional risk factors
The Use of Combustion Reactions for Processing Mineral Raw Materials: Metallothermy and Self-propagating High-temperature Synthesis (Review)
Search for gravitational-wave signals associated with gamma-ray bursts during the second observing run of Advanced LIGO and Advanced Virgo
We present the results of targeted searches for gravitational-wave transients associated with gamma-ray bursts during the second observing run of Advanced LIGO and Advanced Virgo, which took place from 2016 November to 2017 August. We have analyzed 98 gamma-ray bursts using an unmodeled search method that searches for generic transient gravitational waves and 42 with a modeled search method that targets compact-binary mergers as progenitors of short gamma-ray bursts. Both methods clearly detect the previously reported binary merger signal GW170817, with p-values of <9.38 × 10−6 (modeled) and 3.1 × 10−4 (unmodeled). We do not find any significant evidence for gravitational-wave signals associated with the other gamma-ray bursts analyzed, and therefore we report lower bounds on the distance to each of these, assuming various source types and signal morphologies. Using our final modeled search results, short gamma-ray burst observations, and assuming binary neutron star progenitors, we place bounds on the rate of short gamma-ray bursts as a function of redshift for z ≤ 1. We estimate 0.07–1.80 joint detections with Fermi-GBM per year for the 2019–20 LIGO-Virgo observing run and 0.15–3.90 per year when current gravitational-wave detectors are operating at their design sensitivities