Cosmic ray modulation in a random anisotropic magnetic field

Inhomogeneities of the interplanetary magnetic field can be divided into small scale and large scale ones as may be required by the character of the problem of cosmic ray (CR) propagation. CR propagation in stochastic magnetic fields is of diffusion character. The main contribution into the scattering of CR particles is made by their interaction with inhomogeneities of the magnetic field H which have characteristic dimensions 1 of the order of Larmor radius R=cp/eH of particle (p is the absolute value of particle momentum, e is particle charge, c is velocity of light). Scattering of particles on such inhomogeneities leads to their diffusion mostly along a magnetic field with characteristic dimensions of variation in space exceeding the mean free path

Assessment of Nutritive Status in Patients with Symptoms of Heart Failure

Aim of the research. To study the parameters of nutritional status of patients with acute and chronic coronary syndromes and symptoms of heart failure in conjunction with clinical, anthropometric, laboratory parameters, structural and functional characteristics of the heart. Materials and methods. A cross-sectional study of 106 patients with acute and chronic coronary syndromes and symptoms of heart failure. All subjects underwent an integrated assessment of the nutritional status (anthropometric, caliperometric (caliper metric) indicators, CONUT scale (lymphocytes, total cholesterol, albumin), hormonal indicators (N-terminal brain natriuretic propeptide), structural changes in the myocardium using echocardiography, exercise tolerance by 6-minute walk test. Results. Nutritional deficiency, according to CONUT scale, was found in 81.1 % of cases (86 patients). In the group of patients with the presence of malnutrition, there were significantly high level of fibrinogen and N-terminal brain natriuretic propeptide. The interpretation of changes in body composition showed a significant upward trend in the prognostic index of hypotrophy and a decrease in lean body mass as heart failure progresses. The dependence of nutritive insufficiency on the CONUT scale with laboratory parameters (creatinine, fibrinogen, brain natriuretic propeptide), structural and functional characteristics of the heart (diastolic and systolic dimensions of the left ventricle, ejection fraction, left ventricular myocardial mass index), a functional indicator of tolerance to the physical load (6-minute walk test) was determined. Conclusion. An integrated analysis of nutritional status indicators of patients with heart failure revealed an increase of malnutrition signs with an increase of the severity of HF. Pathological effects of nutritional deficiency are associated with impaired left ventricular systolic function, reduced exercise tolerance

Визначення залежності характеристик компресійної піни

One of the promising ways to combat forest fires is considered. The authors suggest using compression foam as an extinguishing agent instead of ordinary water, which has several advantages. Unlike conventional foam, it has special properties that are not characteristic of the ordinary foam, such as increased stability, enhanced adhesion and fire extinguishing ability while reducing the flow of water and foaming agent. In order to increase the effective use of this extinguishing medium, we performed the theoretical substantiation of the dependence of operational characteristics of the compression foam depending on the geometric dimensions and homogeneity of the bubbles it is made up if. The notion of conditional relative strength of the bubble as a value of the ratio of the area of ​​the central transverse section of the bubble to its bubble mass is introduced and the formulas for its deduction are given. The experimental dependences of the operational characteristics of the compression foam on the geometrical sizes and the homogeneity of the bubbles forming it, which will allow creating effective systems for the formation of a compressive foam, and controlling the processes of foaming and fire extinguishing, are presented. The results of the studies confirm that the values ​​of the diameters of the bubbles of the compression foam and their homogeneity, characterized by the polydispersity of the foam, determine its multiplicity, which in turn determines the stability and adhesion properties of the foam. With an increase in the frequency of foam, the polydispersity decreases, i.e., homogeneity increases. It has been proved that there is a direct relationship between the operational characteristics of the compression foam such as the foam stability, the adhesive property of the foam, the fire-extinguishing ability of the foam and its geometric characteristics – the size of the bubbles and their homogeneity, in which the size of the bubbles and their homogeneity (polydispersity) are the determining parameters of compression foam for its performance. Technological solutions aimed at reducing the size of foam bubbles and enhancing their uniformity will lead to improved performance of the compression foam in order to increase the fire-extinguishing capabilities of the compression foam in the fight against forest fires.Проведено теоретичне обґрунтування залежності експлуатаційних характеристик компресійної піни залежно від геометричних розмірів та однорідності бульбашок, що її утворюють. Введено поняття умовної відносної міцності бульбашки як величину відношення площі центрального поперечного перетину бульбашки до її маси бульбашки та наведено формули для його вирахування. Наведено експериментальні залежності експлуатаційних характеристик компресійної піни від геометричних розмірів та гомогенності міхурів, що її утворюють, що дає змогу створювати ефективні системи з утворення КП та здійснювати управління процесами піноутворення та пожежогасіння. Результати досліджень підтверджують, що величини діаметрів міхурів КП та їхня гомогенність, що характеризується полідисперсністю піни, визначають її кратність, яка визначає стійкість та адгезійні властивості піни. У разі збільшення кратності піни, полідисперсність зменшується, тобто гомогенність зростає. Доведено, що існує прямий зв'язок між експлуатаційними характеристиками компресійної піни, такими як: стійкість піни, адгезійна властивість піни, вогнегасна здатність піни та її геометричними характеристиками – розмірами бульбашок та їхня гомогенністю, при чому розміри міхурів та їх гомогенність (полідисперсність) є визначальними параметрами компресійної піни щодо її експлуатаційних характеристик. Технологічні рішення, спрямовані на зменшення розміру бульбашок піни та підвищення її однорідності призведуть до покращення експлуатаційних характеристик компресійної піни та її подальшого впровадження для підвищення ефективності гасіння лісних пожеж

Electron spin resonance detection and identification of nitrogen centers in nanodiamonds

Individual nitrogen centers N0 and nitrogen pairs N 2 + have been detected and identified in natural diamond nanocrystals by means of the high-frequency electron spin resonance method. The N0 nitrogen centers have been observed in synthetic diamond nanocrystallites with a size of less than 10 nm produced by high-temperature high-pressure sintering of detonation nanodiamonds. Thus, the possibility of the stable state of impurity nitrogen atoms in diamond nanoparticles has been demonstrated. © 2009 Pleiades Publishing, Ltd

Efficacy of Angio-Seal Device for Primary And Complicated Haemostasis: a Multicentre Retrospective Assay

Background. Femoral approach in endovascular surgery remains relevant being, however, associated with the risk of fatal and non­fatal complications. Modern techniques for instrumental haemostasis achieved with the Angio­Seal device (Terumo Corporation, Japan) provide an opportunity to reduce the number of fatal and non­fatal complications. Aim. A multicentre assay of the efficacy and safety of instrumental puncture closure using Angio­Seal devices (Terumo Corporation, Japan) in various settings and clinical situations.Materials and methods. A multicentre retrospective analysis of 1088 use cases of the Angio­Seal device  (Terumo Corporation, Japan) for “primary” and “complicated” instrumental haemostasis after femoral access  has been conducted for the years 2018–2020. The mean patient age was 62.3 ± 11.6 years, including 845 men (78.0%) and 243 women (22.0%). Five centres for routine and emergency endovascular radiology participated in the study.Results. The Angio­Seal device (Terumo Corporation, Japan) demonstrated a high method efficiency, with a  97.0% success rate of “primary” instrumental haemostasis (1055 of 1088 total successful haemostatic  procedures) in various clinical settings. Arterial thrombosis at the approach side had a 3.0% complication rate  (5 of 33 observations), all other complication types associated with haemorrhagic events (8 cases) or device malfunction and damage (20 cases).Discussion. The assay conducted suggests that the incidence of “complicated” instrumental haemostasis  relates to technical drawbacks of the device application that required advance planning. The key identified  prerequisites for a successful Angio­Seal application (Terumo Corporation, Japan) are the alignment of anchor tube­delivery through soft tissue into the vessel lumen and its positioning inside the vessel.Conclusion. The constructive features and instrumental haemostatic technique realised in the Angio­Seal  device (Terumo Corporation, Japan) enable an effective and safe primary sealing of arterial puncture site in 97% cases

Detection and identification of nitrogen centers in nanodiamond: EPR studies

Electron paramagnetic resonance (EPR) and electron spin echo (ESE) at X-band and at high-frequency W-band (95 GHz) have been used to study natural diamond nanocrystals, detonation nanodiamond (ND) with a size of ∼ 4.5 nm and detonation ND after high-temperature, high-pressure sintering with a size of ∼ 8.5 nm. Isolated nitrogen centers N 0 and nitrogen pairs N2+ have been detected and identified, and their structure has been unambiguously determined by means of the high frequency EPR and ESE in natural diamond nanocrystals. In detonation ND and detonation ND after sintering, isolated nitrogen centers N 0 have been discovered in nanodiamond core. In addition EPR signals of multivacancy centers with spin 3/2 seem to be observed in nanodiamond core of detonation ND. Copyright © Taylor & Francis Group, LLC

Mechanisms of charge transfer and electronic properties of Cu2ZnGeS4 from investigations of the high field magnetotransport

Recent development of the thin film solar cells, based on quaternary compounds, has been focused on the Ge contain compounds and their solid solutions. However, for effective utilization of Cu2ZnGeS4, deeper investigations of its transport properties are required. In the present manuscript, we investigate resistivity, amp; 961; T , magnetoresistance and Hall effect in p type Cu2ZnGeS4 single crystals in pulsed magnetic fields up to 20 T. The dependence of amp; 961; T in zero magnetic field is described by the Mott type of the variable range hopping VRH charge transfer mechanism within a broad temperature interval of 100 200 K. Magnetoresistance contains the positive and negative components, which are interpreted by the common reasons of doped semiconductors. On the other hand, a joint analysis of the resistivity and magnetoresistance data has yielded series of important electronic parameters and permitted specification of the Cu2ZnGeS4 conductivity mechanisms outside the temperature intervals of the Mott VRH conduction. The Hall coefficient is negative, exhibiting an exponential dependence on temperature, which is quite close to that of amp; 961; T . This is typical of the Hall effect in the domain of the VRH charge transfer

Detection and identification of nitrogen defects in nanodiamond as studied by EPR

Electron paramagnetic resonance (EPR) and electron spin echo (ESE) at X-band and at high-frequency W-band (95 GHz) have been used to study defects in natural diamond nanocrystals, detonation nanodiamond (ND) with a size of ∼4.5 nm and detonation ND after high-temperature, high-pressure sintering with a size of ∼8.5 nm. Atomic nitrogen centers N0 and nitrogen pairs N2 + have been detected and identified and their structure has been unambiguously determined by means of the high frequency EPR and ESE in natural diamond nanocrystals. In detonation ND and detonation ND after sintering atomic nitrogen centers N0 have been discovered in nanodiamond core. In addition EPR signal of multi-vacancy centers with spin 3/2 seems to be observed in diamond core of detonation ND. © 2009 Elsevier B.V. All rights reserved

Nitrogen centers in nanodiamonds: EPR studies

Electron paramagnetic resonance (EPR) and electron spin echo (ESE) at X-band (9.4 GHz) and W-band (94 GHz) have been used to study defects in natural diamond nanocrystals, detonation nanodiamond (ND) with a size of ∼ 4.5 nm and detonation ND after high-pressure hightemperature (HTHP) sintering with a size of ∼ 8.5 nm. Based on identification of atomic nitrogen centers N0 and nitrogen pairs N2 + detected by means of the high frequency EPR and ESE in natural diamond nanocrystals, atomic nitrogen centers N0 have been discovered in nanodiamond core in detonation ND and detonation ND after sintering. In addition EPR signal of multi-vacancy centers with spin 3/2 seems to be observed in diamond core of detonation ND. © (2010) Trans Tech Publications