43 research outputs found
The main peculiarities of the processes of the deformation and destruction of lunar soil
The main results of study of the physical and mechanical properties of lunar soil, obtained by laboratory study of samples returned from the moon by Luna 16 and Luna 20, as well as by operation of the self-propelled Lunokhod 1 and Lunokhod 2 on the surface of the moon, are analyzed in the report. All studies were carried out by single methods and by means of unified instruments, allowing a confident comparison of the results obtained. The investigations conducted allowed the following values of the main physical-mechanical properties of lunar soil to be determined: in the natural condition the solid density corresponds to the porosity of 0.8; the modal value of the carrying capacity is 0.4 kg/square cm; adhesion is 0.04 to 0.06 kg/square cm; and the internal angle of friction is 20 to 25 degree. The main mechanisms of deformation and destruction of the soil are analyzed in the report, and the relationships between the mechanical properties and physical parameters of the soil are presented
РАСЧЕТ ДЛИНЫ И ШИРИНЫ РАСКРЫТИЯ ТРЕЩИНЫ, РАЗВИВАЮЩЕЙСЯ ВО ВРЕМЕНИ
The executed investigations make it possible to calculate crack’s length and opening development in the concrete elements.Выполненные исследования дают возможность проводить расчет длины и ширины раскрытия трещины в железобетонных элементах
ФИЗИКО-ХИМИЧЕСКИЕ ОСНОВЫ ТЕХНОЛОГИИ РЕМОНТА ЖЕЛЕЗОБЕТОННЫХ КОНСТРУКЦИЙ
The paper presents a brief review of new methods for repair of concrete and reinforced concrete products, structures etc. The review demonstrates that the usage of diffusion processes proceeding in the porous materials makes it possible to obtain positive effects while performing repair works. Представлен краткий обзор новых подходов к ремонту бетонных и железобетонных изделий, конструкций и т. д., из которого следует, что использование диффузионных процессов, протекающих в пористых материалах, позволяет достичь положительных эффектов при проведении ремонтных рабо
The MHD nature of ionospheric wave packets excited by the solar terminator
We obtained the first experimental evidence for the magnetohydrodynamic (MHD)
nature of ionospheric medium-scale travelling wave packets (MSTWP). We used
data on total electron content (TEC) measurements obtained at the dense
Japanese network GPS/GEONET (1220 stations) in 2008-2009. We found that the
diurnal, seasonal and spectral MSTWP characteristics are specified by the solar
terminator (ST) dynamics. MSTWPs are the chains of narrow-band TEC oscillations
with single packet's duration of about 1-2 hours and oscillation periods of
10-20 minutes. Their total duration is about 4--6 hours. The MSTWP spatial
structure is characterized by a high degree of anisotropy and coherence at the
distance of more than 10 wavelengths. The MSTWP direction of travelling is
characterized by a high directivity regardless of seasons. Occurrence rate of
daytime MSTWPs is high in winter and during equinoxes. Occurrence rate of
nighttime MSTIDs has its peak in summer. These features are consistent with
previous MS travelling ionosphere disturbance (TID) statistics obtained from
630-nm airglow imaging observations in Japan. In winter, MSTWPs in the northern
hemisphere are observed 3-4 hours after the morning ST passage. In summer,
MSTWPs are detected 1.5-2 hours before the evening ST occurrence at the point
of observations, at the moment of the evening ST passage in the
magneto-conjugate point. Both the high Q-factor of oscillatory system and
synchronization of MSTWP occurrence with the solar terminator passage at the
point of observations and in the magneto-conjugate area testify the MHD nature
of ST-excited MSTWP generation. The obtained results are the first experimental
evidence for the hypothesis of the ST-generated ion sound waves.Comment: 12 pages, 3 figure
The study of the dynamics of clinical and laboratory-instrumental parameters in hypertensive patients with obesity who underwent COVID-19-associated pneumonia
BACKGROUND: According to the results of the ESSE-RF study, the frequency of obesity in the population reached 29.7%. Obesity is one of the main risk factors for the development of cardiovascular diseases. Features of the course of COVID-19 in patients with obesity is a very urgent problem.AIM: The aim of the study was a comparative investigation of clinical and laboratory-instrumental parameters in AH patients with or without obesity who had COVID-19 associated pneumonia, to identify the role of obesity as a potential predictor of post-COVID cardiovascular complications 3 months after discharge from the hospital.MATERIALS AND METHODS: Materials and methods. The study included 174 patients with COVID-19-associated pneumonia. Group 1 included 78 patients with AH without obesity, group 2 — 96 patients with AH and obesity. All patients were tested with a blood sample at the time of admission and 3 months after discharge from the hospital. We assessed parameters of general blood test, biochemistry, hemostasis, inflammation biomarkers — concentration of C-reactive protein (CRP), highly sensitive CRP (hs-CRP), homocysteine, IL-6, etc. All patients initially underwent computed tomography of the chest. In both groups, 24-hour blood pressure monitoring was performed using BPLaB device, according to the standard protocol; echocardiography using an expert class ultrasound diagnostic system Vivid S70. The study is registered with the Clinical Trials.gov database Identifier: NCT04501822.RESULTS: Results. The biomarker that significantly distinguished the both groups of patients, as well as subgroups according to the degree of obesity was the concentration of maxCRP and hs-CRP, which was significantly higher in group 2. In addition, the registered maximum values of MPO, NT-proBNP, IL-1,6, TNA-α and NRL parameters in group 2 of patients with 2–3 degrees of obesity, may indicate the highest probability of developing delayed adverse cardiovascular complications in this group of patients. Mean systolic blood pressure, variability of systolic and diastolic blood pressure, and heart rate at night were significantly higher in AH patients with obesity. Numerous correlations of obesity with laboratory and instrumental parameters have been registered, which may indicate an increased likelihood of delayed unwanted cardiovascular complications in this particular group of patients. Multiple regression showed that obesity is an independent predictor of an increase in LDH, hs-CRP and right atrium.CONCLUSION: Dynamic control of the studied parameters in patients with AH and OB registered an increased concentration of CRP at the initial stage and 3 months after treatment, with a general trend towards a decrease in the increased initial structural parameters of ECHO CG. The logistic regression method showed that the presence of OB in patients with AH is an independent factor causing increased levels of immune inflammation (CRP), a marker of tissue destruction (LDH), and load on the right atrium
Опыт лечения гангрены Фурнье, осложненной развитием перитонита
Fournier’s gangrene (FG) is a rare but rather formidable disease that has been occurring more and more often in surgical hospitals of the country in the last decade. Such situation, in our opinion, is explained by an increase in the number of immunocompromised patients. A number of concomitant diseases is a predisposing factor for the development of FG: diabetes mellitus, obesity, cirrhosis, malignant tumors, alcoholism, drug addiction, glucocorticoids, condition after chemotherapy, nutritional deficiency. The course of the disease is accompanied by a high mortality rate – up to 88.0 %, and among the surviving patients, about 30.0 % need constant care after discharge from the hospital and more than 50.0 % – in repeated reconstructive and plastic surgeries on the genitals and perineum. Annually in our clinic, up to 5–6 people are hospitalized with this diagnosis. In this article, we present a rare clinical observation of the treatment a patient with FG, complicated by the development of peritonitis with a favorable outcome.Гангрена Фурнье (ГФ) – редкое, но довольно грозное заболевание, которое в последнее десятилетие встречается в хирургических стационарах страны все чаще. Такая ситуация, на наш взгляд, объясняется увеличением количества иммунокомпрометированных пациентов. Ряд сопутствующих заболеваний является предрасполагающим фактором для развития ГФ: сахарный диабет, ожирение, цирроз печени, злокачественные опухоли, алкоголизм, наркомания, прием глюкокортикостероидов, состояние после химиотерапии, алиментарная недостаточность. Течение заболевания сопровождается высокой летальностью – до 88,0 %, а среди выживших пациентов около 30,0 % нуждаются в постоянном уходе после выписки из стационара и более 50,0 % – в повторных реконструктивных и пластических операциях на наружных гениталиях и промежности. Ежегодно в нашу клинику госпитализируется до 5–6 человек с данным диагнозом. В этой статье мы приводим редкое клиническое наблюдение лечения пациента с ГФ, осложнившейся развитием перитонита, с благоприятным исходом.Конфликт интересов. Авторы заявляют об отсутствии конфликта интересов.Финансирование. Исследование не имело спонсорской поддержки