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BACKGROUND. There is enough evidence of the negative impact of excess weight on the formation and progression of res piratory pathology. Given the continuing SARS-CoV-2 pandemic, it is relevant to determine the relationship between body mass index (BMI) and the clinical features of the novel coronavirus infection (NCI).AIM. To study the effect of BMI on the course of the acute SARS-COV-2 infection and the post-covid period.MATERIALS AND METHODS. AKTIV and AKTIV 2 are multicenter non-interventional real-world registers. The АКТИВ registry (n=6396) includes non-overlapping outpatient and inpatient arms with 6 visits in each. The АКТИВ 2 registry (n=2968) collected the data of hospitalized patients and included 3 visits. All subjects were divided into 3 groups: not overweight (n=2139), overweight (n=2931) and obese (n=2666).RESULTS. A higher BMI was significantly associated with a more severe course of the infection in the form of acute kidney injury (p=0.018), cytokine storm (pCONCLUSION. Overweight and/or obesity is a significant risk factor for severe course of the new coronavirus infection and the associated cardiovascular and kidney damage Overweight people and patients with the 1st and 2nd degree obesity tend to have a high risk of death of SARS-CoV-2 infection in both acute and post-covid periods. On top of that, in case of morbid obesity patients this tendency is statistically significant. Normalization of body weight is a strategic objective of modern medicine and can contribute to prevention of respiratory conditions, severe course and complications of the new coronavirus infection.

Aim. To analyze newly diagnosed diseases and features of the post-COVID course in patients after a coronavirus disease 2019 (COVID-19) within 12-month follow-up.Material and methods. A total of 9364 consecutively hospitalized patients were included in the ACTIV registry. Enrollment of patients began on June 29, 2020, and was completed on March 30, 2021, corresponding to the first and second waves of the pandemic. Demographic, clinical, and laboratory data, computed tomography (CT) results, information about inhospital clinical course and complications of COVID-19 during hospitalization were extracted from electronic health records using a standardized data collection form. The design included follow-up telephone interviews with a standard questionnaire at 3, 6, and 12 months to examine the course of post-COVID period.Results. According to the ACTIV registry, 18,1% of patients after COVID-19 had newly diagnosed diseases (NDDs) over the next 12 months. Hypertension (HTN), type 2 diabetes and coronary artery disease (CAD) prevailed in the NDD structure. Comparison of the age-standardized incidence of NDDs (HTN, CAD, diabetes) in the post-COVID period in the ACTIV registry with NDD incidence in 2019 according to Rosstat and the expected incidence of NDDs according to the EPOHA study revealed that HTN, diabetes, CAD in patients after COVID-19 were registered more often as follows: HTN by 7,0 and 4,4 times, diabetes by 7,3 and 8,8 times, CAD by 2,3 and 2,9 times, respectively. NDDs most often developed in patients aged 47 to 70 years. Comparison of the actual and expected number of cases of newly diagnosed HTN, CAD and diabetes depending on age showed that the actual number of cases in the population of patients in the ACTIV register is significantly higher than expected for patients aged 45-69 years and for patients with hypertension or diabetes and aged Conclusion. Available evidence suggests that a strategy for managing COVID-19 survivors should include mandatory screening for early detection of cardiovascular disease and diabetes, which will be key to reducing the risk of further COVID-19 consequences.

Purpose of the study. To assess the quality of diagnosis cerebrovascular accident (CA) at the pre-hospital stage in patients brought to the regional vascular center. Material and methods. 2708 case histories of the emergency department and accompanying sheets of first aid in patients with a guiding diagnosis of CA and 973 medical records of impatient in the regional vascular center were analyzed. Results and conclusion. Of the 2708 patients admitted with a diagnosis of CA, 973 people were hospitalized. Among hospitalized patients, the diagnosis of stroke was confirmed in 96.5% of cases. The most frequent diseases that were mistakenly diagnosed as a stroke turned out to be: diabetes, traumatic brain injury and brain neoplasms, etc. Confirmation of the guiding diagnosis during self-circulation was 36.6%, when delivered by ambulance crews — 39.8%, air ambulance — 86.7% and by sanitary transport — 16.5% of cases.

Aim To study the effect of regular drug therapy for cardiovascular and other diseases preceding the COVID-19 infection on severity and outcome of COVID-19 based on data of the ACTIVE (Analysis of dynamics of Comorbidities in paTIents who surVived SARS-CoV-2 infEction) registry.Material and methods The ACTIVE registry was created at the initiative of the Eurasian Association of Therapists. The registry includes 5 808 male and female patients diagnosed with COVID-19 treated in a hospital or at home with a due protection of patients’ privacy (data of nasal and throat smears; antibody titer; typical CT imaging features). The register territory included 7 countries: the Russian Federation, the Republic of Armenia, the Republic of Belarus, the Republic of Kazakhstan, the Kyrgyz Republic, the Republic of Moldova, and the Republic of Uzbekistan. The registry design: a closed, multicenter registry with two nonoverlapping arms (outpatient arm and in-patient arm). The registry scheduled 6 visits, 3 in-person visits during the acute period and 3 virtual visits (telephone calls) at 3, 6, and 12 mos. Patient enrollment started on June 29, 2020 and was completed on October 29, 2020. The registry completion is scheduled for October 29, 2022. The registry ID: ClinicalTrials.gov: NCT04492384. In this fragment of the study of registry data, the work group analyzed the effect of therapy for comorbidities at baseline on severity and outcomes of the novel coronavirus infection. The study population included only the patients who took their medicines on a regular basis while the comparison population consisted of noncompliant patients (irregular drug intake or not taking drugs at all despite indications for the treatment).ResultsThe analysis of the ACTIVE registry database included 5808 patients. The vast majority of patients with COVID-19 had comorbidities with prevalence of cardiovascular diseases. Medicines used for the treatment of COVID-19 comorbidities influenced the course of the infectious disease in different ways. A lower risk of fatal outcome was associated with the statin treatment in patients with ischemic heart disease (IHD); with angiotensin-converting enzyme inhibitors (ACEI)/angiotensin receptor antagonists and with beta-blockers in patients with IHD, arterial hypertension, chronic heart failure (CHF), and atrial fibrillation; with oral anticoagulants (OAC), primarily direct OAC, clopidogrel/prasugrel/ticagrelor in patients with IHD; with oral antihyperglycemic therapy in patients with type 2 diabetes mellitus (DM); and with long-acting insulins in patients with type 1 DM. A higher risk of fatal outcome was associated with the spironolactone treatment in patients with CHF and with inhaled corticosteroids (iCS) in patients with chronic obstructive pulmonary disease (COPD).Conclusion In the epoch of COVID-19 pandemic, a lower risk of severe course of the coronavirus infection was observed for patients with chronic noninfectious comorbidities highly compliant with the base treatment of the comorbidity.

The cathodoluminescence spectra of polycrystalline CVD ZnSxSe1−x alloy layers grown with the Zn excess are investigated. The dependence E g(x) is refined taking into account the location of exciton bands at 300 K. It is confirmed that the spectra are reconstructed on dissolving oxygen in the lattice under the effect of high pressures and temperatures of the gas-static treatment. The dependence of the self-activated emission on the alloy composition is observed for the accepted conditions of the gas-static treatment. For the compositions close to ZnSe (x 0.7), which is also most typical of the compounds themselves. These specific features are interpreted based on the calculations of the equilibrium of intrinsic point defects, which affect the location of the Fermi level under the deviation of ZnSe and ZnS from stoichiometry. The spectral regions, in which the bands of oxygen-containing SA and SAL complexes in the ZnSxSe1-x alloy can be observed, are evaluated. These regions depend on x and the oxygen concentration at the lattice sites. The behavior of exciton bands and infrared radiation emerging in the Cu (3d 9) ions is investigated after the gas-static treatment. It is shown that the variation in the ensemble of intrinsic point defects during the gas-static treatment is determined by an increase in the number of defects with a smaller volume, specifically, the SSe antisite defects. The spectra are interpreted based on the theory of nonoverlapping bands, which are induced by the isoelectronic impurity.

Experimental data indicating that the band gap of Zn-O-S solid solutions decreases appreciably in accordance with the theory of noncrossing energy bands are reported for the first time. It is shown that this effect is mainly characteristic of ZnS with an excess of Zn. The concentration of dissolved oxygen [OS] has been determined from data taken using precision X-ray structure analysis and chemical phase analysis. The decrease in the band gap determined from the cathodoluminescence spectra is equal to 75 meV for sphalerite ZnS (s) and 90 meV for wurtzite ZnS (w) per 1 mol % and depends virtually linearly on the oxygen concentration [OS]. An increase in [OS], in addition to an intensification and shift of the free-exciton (FE) band, is also conducive to the formation of SA oxygen-containing complexes in ZnS. These complexes are responsible for emission in the visible region of the spectrum and for the band I1 of excitons bound to these complexes. The binding energy is equal to ∼61 and ∼104 meV for ZnS (s) and ZnS (w), respectively. The band I1 shifts as [OS] varies, similarly to the shift of the FE band. The obtained dependences define the position of the FE band in oxygen-free ZnS and make it possible to assess the oxygen concentration in the compound from the shift of the FE band.

The pressure (100–200 MPa) and temperature (900–1100°C) effects on the equilibria of native point defects and background impurities in Zn-enriched ZnS are studied using cathodoluminescence and transmission spectra. The optimal conditions are found under which high pressures and temperatures accelerate migration of defects and impurities. The associated structural and compositional changes are studied by scanning electron microscopy. The increase in the concentration of dissolved oxygen at high pressures and temperatures is accompanied by a reduction in the band gap of ZnS, growth and blue shift (to 395–400 nm) of the shorter wavelength component of the SA blue emission in ZnS, and quenching of the longer wavelength component (445 nm). In addition, at 300 K a free-exciton bandI 1 emerges at 342 nm. It is shown that the data available in the literature can be used to evaluate the concentration of dissolved oxygen in ZnS · O from its band gap. The effects of different oxygen species on the transmission of ZnS are studied in the range 3.5–15 μm.

The cathodoluminescence and optical-transmission spectra of ZnS were analyzed to study the effect of a high hydrostatic gas pressure (1500 atm at 1000°C) on the equilibrium between intrinsic point defects in zinc sulfide grown by chemical vapor deposition (CVD) with an excess of zinc. The cathodoluminescence spectra were measured at 80–300 K and excitation levels of 1022 and 1026 cm−3 s−1; the optical-transmission spectra were measured at 300 K in the wavelength range 4–12 µm. It is found that exposure to a high hydrostatic gas pressure transforms the self-activated emission in the cathodoluminescence spectrum: (i) a new short-wave-length band appears at 415 nm with its intensity increasing by one to three orders of magnitude; and (ii) the long-wavelength band that peaks at 445 nm and is observed in as-grown crystals becomes quenched. Simultaneously, the cathodoluminescence band peaked at 850 nm and related to vacancies VS is no longer observed after high-pressure treatment. These effects are attributed to a partial escape of excess zinc (Zni) from crystals and additional incorporation of oxygen into lattice sites (OS). A doublet band I1, which peaked at ∼331–332 nm at 80 K and at ∼342–343 nm at 300 K and is related to excitons bound to acceptor levels of oxygen centers, was observed. This band is found to be dominant in the cathodoluminescence spectrum at an excitation level of 1026 cm−3 s−1. Traces of the ZnO phase are apparent after the high-pressure treatment in both the cathodolumi-nescence spectra (the bands at 730 and 370 nm) and the transmission spectra (narrow bands in the region of 6–7 µm).

ZnSe was doped with Cu via thermal diffusion from Cu foil in the course of chemical vapor deposition. The Cu distribution over the deposit was studied, and the Cu solubility in ZnSe was determined as a function of temperature. Copper was shown to prevent oxygen incorporation from the gas phase. The microstructure and homogeneity of ZnSe were studied by scanning electron microscopy. The cathodoluminescence (CL) spectra were measured on fracture surfaces in order to elucidate the origin of the Cu-related emission centers. Heavy doping with Cu was shown to gives rise to a long-wavelength CL band, which shifts from 525 to 550 nm as the temperature is raised from 80 to 300 K. The associated changes in oxygen-related self-activated luminescence were correlated with the Cu and O concentrations. To gain more detailed insight into the origin of the green Cu-related emission in p-type ZnSe, we examined its photoexcitation spectrum, temperature-dependent peak position, quenching, and variation with excitation intensity. The conclusion is drawn that the longer wavelength CL bands are due to electron transitions from the Zni·· donor level to the impurity band. The CL spectrum of heavily doped ZnSe shows no emissions between 800 and 1400 nm, related to the VSe and VZn vacancies.

The results of studying the poorly understood 700-to 2000-nm spectral region in ZnSe cathodoluminescence of condensates deposited from the vapor phase with deviations from stoichiometry and Cu and O introduction into a pure matrix are reported. The nature of cathodoluminescence in the region of 1300–1400 nm is refined: the conclusion is drawn that the emission is caused by isolated V Zn () vacancies. The behavior of V Se-related luminescence bands at 830 and 960 nm, when the matrix composition changes, is considered.

The effect of oxygen doping (0.9 and 4.3 vol % O2in the gas phase) on the transmission and cathodoluminescence of CVD ZnSe was studied. The incorporation of oxygen was found to reduce the transmission in the spectral range 700–1900 cm–1. Examination by scanning electron microscopy shows that Se excesses and high O2concentrations lead to tabular growth. ZnO precipitation at structural defects during cooling was observed only in the end portion of the deposit. The dimensions of microinhomogeneities are shown to have a significant effect on the transmission of ZnSe. The oxygen-containing species present in the deposits were identified using cathodoluminescence spectra. The CL spectrum of Se-enriched p-type ZnSe is dominated by the band at 490 nm (SAL) at 80 K and the band at 640 nm (SA) at 300 K. The 640-nm band is attributed to recharging of the SALcenters upon a variation of the Fermi energy with temperature. Decreasing the Se excess leads to the quenching of the SALemission and appearance of the shorter wavelength component of the SAband at 600 nm (80–300 K), characteristic of slightly Zn-enriched ZnSe. The intensity of the self-activated bands is shown to increase as the concentration of dissolved oxygen increases.

The effects of deviation from stoichiometry and the copper and oxygen concentrations on cathodoluminescence spectra were studied in ZnSe condensates obtained by chemical vapor deposition and doped with Cu during growth. The results were supplemented with the study of the microstructure and microcomposition using scanning electron microscopy, measurements of electrical conductivity, and calculations of the equilibrium between the native point defects. It is shown that three types of Cu-related centers are always accompanied with self-activated centers that include oxygen at the Se lattice site (OSe). The paired centers SA(I)-Cu(I), SAL(II)-Cu(II), and III-Cu(III) are typical of all II-VI compounds. All observed I-III Cu-containing centers are associative. Models of emission centers are suggested. A change of the emission type I-III is related to the recharging of the same group of defects that include OSe, Zn(Cu), and V Zn. New phenomena that occurred in the region of I-III bands and were related to the profound purification of the material were observed.

An investigation is made of the cathodoluminescence, electrical properties, and structural features of crystals of Cd1−xZnxTe solid solutions with composition x ranging from 0.02 to 0.20 mole fraction as compared with CdTe and ZnTe. The main bands of the cathodoluminescence spectra are identified within the range 500–2700 nm. The role of oxygen in Cd1−xZnxTe cathodoluminescence is shown.

Coordinated investigations of cathodoluminescence spectra, microstructure, specific resistance and presence of oxygen in Cd 12x Zn x Te crystals are used to identify how the electrical properties and degree of perfection of the crystal lattice of these materials are affected by the form in which oxygen is present as an intrinsic point defect. It is found that oxygen, which is the main background impurity in Cd12xZnxTe, forms different types of point defects at different positions in the lattice, depending on the ratio @Cd#/@Zn#. The optimum composition for making detectors of ionizing radiation, for which the crystal resistance is highest, is Cd0.77Zn0.23Te. © 1999 American Institute of Physics.@S1063-7826~99!00905-9#

1. Results of stress relaxation tests by two different procedures (compensation and static) for rolled sheet single-crystal molybdenum at room temperature and with initial stresses σ0 < 0.4σ0.2 are close in value. Stress relaxation curves calculated taking account of the change in distribution of bending stresses over the specimen cross section in this region of initial stresses almost coincide with experimental curves. 2. Values of stress relaxation limit on reaching residual strain of 0.001 and 0.005% on a base of 500 h, and also the stress relaxation limit σ nom o = 70 ± 10 MPa below which relaxation does not occur, have been determined in specimens of rolled sheet single-crystal molybdenum. 3. In specimens of rolled single-crystal molybdenum tested with initial stresses of σ0 0.4σ0.2 for 500 h, 90% of the residual strain accumulates in the first 25 h.

A study is made of the cathode luminescence of zinc sulfide of various modifications and structural forms in the temperature range 80–400°K. Laws and temperature coefficients of the shift of the resonance and edge luminescence bands are obtained for perfect specimens and for specimens with stacking defects.

Fine structure in the spectral response in the 300–340 nm range is reported for polycrystalline films at 90 ° and 293 ° K. The response spectrum is compared with the absorption and reflection spectra; peaks in absorption correspond to minima in the photocurrent. The detailed spectrum is dependent on the modification and on the structure defects.

The results presented are of an investigation into the photoelectric properties of polycrystalline cadmium sulfide layers obtained by thermal evaporation in vacuum. In producing the layers the substrate temperature was varied over the range 80 °–500 ° C, and in addition the layers were heated in air. It was found that the spectral distribution of the photocurrent, the absolute and relative phbtosensitivity, and the relaxation time depend to a marked extent on the substrate temperature. These differences are connected with a change in the degree of defectiveness and phase compositions of the polycrystalline cadmium sulfide layers.