Analysis of model for assessing the road train movement stability

In this paper, we conduct a mathematical analysis of the model of ensuring the road trains movement stability by changing the design of coupling devices to determine the critical characteristic parameters of the road trains, which result in the loss of en-route directional stability under external action. The concept of the model was to separate the process of yawing of the road trains and its elements (due to external perturbing action) on the highway into several typical stages. The main parameters of the stages (the displacement amplitude and rotation angle of the road trains elements in relation to the driving direction) were determined based on the initial conditions of the road trains movement, the force and duration of the external action. The most dangerous areas of external action application to the road trains were determined in this paper. The maximum permissible exposure limit should not exceed 0.5-1.0% of the road trains trailer momentum, with duration having the greater effect than the amount of impact. The results obtained can be used in mechanical engineering to improve the road trains performance. © Published under licence by IOP Publishing Ltd

Model for assessing the road train stability movement

Road trains (RT) are the main transport in agriculture. However, their accident rate is quite high. In the vehicles movement research their design characteristics and operating modes are mainly improved. The main way to reduce the accident rate remains the speed limit. The authors proposed methods (confirmed by the issued patents) for ensuring the stability of the RT movement by changing the design of trailer devices. The purpose of this work is to form a mathematical model for assessing the stability of the RT movement in the presence of side effects (modeling of sharp turns, impacts). Methods of analysis and synthesis, mathematical analysis, and vector geometry were applied. The process of RT yawing on the highway is split into a number of stages, for which the laws of changing its geometry and kinematics are formulated. Side effect leads to increase in the RT impulse (lateral oscillations increase the speed), or to a violation of stability (the movement amplitude goes beyond the highway or tipping). This model can be used to analyze the stability of the RT movement and evaluate methods to influence it in order to reduce the probability of accidents. © 2020 Published under licence by IOP Publishing Ltd

Superlattices Consisting of "Lines" of Adsorbed Hydrogen Atom Pairs on Graphene

The structures and electron properties of new superlattices formed on graphene by adsorbed hydrogen molecules are theoretically described. It has been shown that superlattices of the (n, 0) zigzag type with linearly arranged pairs of H atoms have band structures similar to the spectra of (n, 0) carbon nanotubes. At the same time, superlattices of the (n, n) type with a "staircase" of adsorbed pairs of H atoms are substantially metallic with a high density of electronic states at the Fermi level and this property distinguishes their spectra from the spectra of the corresponding (n, n) nanotubes. The features of the spectra have the Van Hove form, which is characteristic of each individual superlattice. The possibility of using such planar structures with nanometer thickness is discussed.Comment: 5 pages, 4 figure

Лечение острых отравлений парацетамолом

BACKGROUND Currently, despite the optimization of diagnostic methods in order to predict the development of liver damage, improvement of treatment protocols, paracetamol poisoning is a serious problem in medicine, being the most common cause of acute liver failure worldwide.AIM OF STUDY To determine the indications for the use of acetylcysteine in paracetamol poisoning and evaluate the effectiveness of the 21-hour protocol for its administration.MATERIAL AND METHODS We examined 20 patients with acute paracetamol poisoning (15 women and 5 men), the median age was 21.5 (19.8–32.3) years. ALT and AST were assessed during the entire period of stay in the hospital, the time period from the moment of taking paracetamol to hospitalization and the beginning of the administration of ACC, the concentration of paracetamol in the blood, and mortality. According to the level of ALT and AST in the blood, the patients were divided into 2 groups: Group I consisted of 14 patients, in whom the concentration of ALT and AST during the entire observation period did not exceed 50 U/L; in Group II (6 patients), an increase in the level of ALT and AST in the blood of more than 50 U/L was observed. To assess the risk of liver lesion, the Rumack-Matthew nomogram was used. To compare the concentrations of paracetamol in the blood of patients, the paracetamol index was used.RESULTS It was found that in 10 patients with a high risk of liver damage, who were treated with a 21-hour regimen of ACC administration, no hepatotoxic effect was found. The use of ACC according to a 21-hour protocol in patients with initially elevated ALT and AST levels of more than 50 U/L (n = 4) (25%) led to a rapid positive dynamics of laboratory and clinical parameters. It was found that in 2 patients, despite the introduction of ACC, the development of liver damage was observed. At the same time, the level of paracetamol in their blood was 6.6 and 10.6 fold higher than the “therapeutic” line of the nomogram, and the time from the moment of taking the drug to the beginning of the administration of ACC was 8 and 20 hours. High risk factors for the development of hepatotoxic effect in case of paracetamol poisoning are the time range from the moment of taking the drug to the beginning of the administration of ACC and the value of the paracetamol index.CONCLUSION Indications for the use of acetylcysteine in acute poisoning with paracetamol is a high risk of liver damage. Its criteria are high doses, increased concentrations of ALT and AST when patients are admitted to the hospital; if it is possible to determine the concentration of paracetamol in the blood, an increase in the value of the paracetamol index is more than 1. The use of a 21-hour protocol of intravenous administration of acetylcysteine is effective in case of paracetamol poisoning and its early use in the complex of treatment almost always prevents the development of acute liver failure.ВВЕДЕНИЕ В настоящее время, несмотря на оптимизацию методов диагностики с целью прогноза развития поражения печени и совершенствование протоколов лечения, отравление парацетамолом представляет серьезную проблему в медицине, являясь наиболее частой причиной острой печеночной недостаточности во всем мире.ЦЕЛЬ Определить показания к применению ацетилцистеина (АЦЦ) при отравлениях парацетамолом и оценить эффективность 21-часового протокола его введения.МАТЕРИАЛ И МЕТОДЫ Обследованы 20 пациентов с острым отравлением парацетамолом (15 женщин и 5 мужчин), медиана возраста — 21,5 (19,8–32,3) года. Была проведена оценка уровня аланин- (АЛТ) и аспар­татаминотрансфераз (АСТ) в крови на протяжении всего периода нахождения в стационаре, временного диапазона от момента приема парацетамола до госпитализации в стационар и начала введения ацетилцистеина (АЦЦ), концентрации парацетамола в крови и летальности. По уровню АЛТ и АСТ в крови пациенты были разделены на две группы: I группу составили 14 больных, у которых концентрация АЛТ и АСТ в течение всего периода наблюдения не превышала 50 Ед/л; у пациентов II группы (6 больных) отмечали увеличение уровня АЛТ и АСТ в крови более 50 Ед/л. Для оценки риска поражения печени использовали номограмму Рамэка–Мэтью 150. Для сравнения концентрации парацетамола в крови больных был рассчитан индекс парацетамола.РЕЗУЛЬТАТЫ Выявлено, что у 10 пациентов с высоким риском поражения печени, которым в комплекс лечения входило применение 21-часовой схемы введения АЦЦ, гепатотоксический эффект отсутствовал. Использование АЦЦ по 21-часовому протоколу при исходно повышенных уровнях АЛТ и АСТ более 50 Ед/л (n=4) (25%) привело к быстрой положительной динамике лабораторных и клинических показателей. У 2 пациентов, несмотря на введение АЦЦ, наблюдали развитие поражения печени. При этом уровень парацетамола в крови у них был в 6,6 и 10,6 раза выше «лечебной» линии номограммы, а время от момента приема препарата до начала введения АЦЦ составило соответственно 8 и 20 часов. Факторами высокого риска развития гепатотоксического эффекта при отравлении парацетамолом являются: временной диапазон от момента приема препарата до начала введения АЦЦ и величина индекса парацетамола.ЗАКЛЮЧЕНИЕ Показанием к применению ацетилцистеина при острых отравлениях парацетамолом является высокий риск поражения печени. Его критериями служат высокие дозы принятого парацетамола, повышенные концентрации АЛТ и АСТ при поступлении больных в стационар, при наличии возможности определения концентрации парацетамола в крови — увеличение величины индекса парацетамола более 1. Применение 21-часового протокола внутривенного введения ацетилцистеина эффективно при отравлении парацетамолом и раннее его использование в комплексе лечения практически всегда предотвращает развитие острой печеночной недостаточности

АПОПТОЗ КЛЕТОК КРОВИ У ГЕРОНТОЛОГИЧЕСКИХ БОЛЬНЫХ С ОСТРЫМИ ОТРАВЛЕНИЯМИ ПСИХОФАРМАКОЛОГИЧЕСКИМИ ПРЕПАРАТАМИ

We studied apoptosis of peripheral blood cells in 47 patients older than 60 years with varying course and outcome of acute poisoning with psychopharmacological drugs. It is shown that a control group of volunteers of the same age should be formed for an objective assessment of these disturbances. We revealed deviation of apoptotic parameters from the control group values. However, we failed to specify its information value for the prognosis and disease outcomeУ 47 больных старше 60 лет с различным течением и исходом острых отравлений психофарма- кологическими препаратами изучен апоптоз клеток периферической крови. Показано, что для объективной оценки нарушений следует формировать контрольную группу из добровольцев та- кого же возраста. Выявлены отклонения показателей апоптоза от значений контрольной группы. Однако не удалось установить их информативность для прогноза течения и исхода заболевания

Novel facultative Methylocella strains are active methane consumers at terrestrial natural gas seeps

Natural gas seeps contribute to global climate change by releasing substantial amounts of the potent greenhouse gas methane and other climate-active gases including ethane and propane to the atmosphere. However, methanotrophs, bacteria capable of utilising methane as the sole source of carbon and energy, play a significant role in reducing the emissions of methane from many environments. Methylocella-like facultative methanotrophs are a unique group of bacteria that grow on other components of natural gas (i.e. ethane and propane) in addition to methane but a little is known about the distribution and activity of Methylocella in the environment. The purposes of this study were to identify bacteria involved in cycling methane emitted from natural gas seeps and, most importantly, to investigate if Methylocella-like facultative methanotrophs were active utilisers of natural gas at seep sites

A DNA Sequence Directed Mutual Transcription Regulation of HSF1 and NFIX Involves Novel Heat Sensitive Protein Interactions

BACKGROUND: Though the Nuclear factor 1 family member NFIX has been strongly implicated in PDGFB-induced glioblastoma, its molecular mechanisms of action remain unknown. HSF1, a heat shock-related transcription factor is also a powerful modifier of carcinogenesis by several factors, including PDGFB. How HSF1 transcription is controlled has remained largely elusive. METHODOLOGY/PRINCIPAL FINDINGS: By combining microarray expression profiling and a yeast-two-hybrid screen, we identified that NFIX and its interactions with CGGBP1 and HMGN1 regulate expression of HSF1. We found that CGGBP1 organizes a bifunctional transcriptional complex at small CGG repeats in the HSF1 promoter. Under chronic heat shock, NFIX uses CGGBP1 and HMGN1 to get recruited to this promoter and in turn affects their binding to DNA. Results show that the interactions of NFIX with CGGBP1 and HMGN1 in the soluble fraction are heat shock sensitive due to preferential localization of CGGBP1 to heterochromatin after heat shock. HSF1 in turn was found to bind to the NFIX promoter and repress its expression in a heat shock sensitive manner. CONCLUSIONS/SIGNIFICANCE: NFIX and HSF1 exert a mutual transcriptional repressive effect on each other which requires CGG repeat in HSF1 promoter and HSF1 binding site in NFIX promoter. We unravel a unique mechanism of heat shock sensitive DNA sequence-directed reciprocal transcriptional regulation between NFIX and HSF1. Our findings provide new insights into mechanisms of transcription regulation under stress

Heart Rate Variability Dynamics for the Prognosis of Cardiovascular Risk

Statistical, spectral, multi-resolution and non-linear methods were applied to heart rate variability (HRV) series linked with classification schemes for the prognosis of cardiovascular risk. A total of 90 HRV records were analyzed: 45 from healthy subjects and 45 from cardiovascular risk patients. A total of 52 features from all the analysis methods were evaluated using standard two-sample Kolmogorov-Smirnov test (KS-test). The results of the statistical procedure provided input to multi-layer perceptron (MLP) neural networks, radial basis function (RBF) neural networks and support vector machines (SVM) for data classification. These schemes showed high performances with both training and test sets and many combinations of features (with a maximum accuracy of 96.67%). Additionally, there was a strong consideration for breathing frequency as a relevant feature in the HRV analysis

Heart Rate Variability Dynamics for the Prognosis of Cardiovascular Risk

Statistical, spectral, multi-resolution and non-linear methods were applied to heart rate variability (HRV) series linked with classification schemes for the prognosis of cardiovascular risk. A total of 90 HRV records were analyzed: 45 from healthy subjects and 45 from cardiovascular risk patients. A total of 52 features from all the analysis methods were evaluated using standard two-sample Kolmogorov-Smirnov test (KS-test). The results of the statistical procedure provided input to multi-layer perceptron (MLP) neural networks, radial basis function (RBF) neural networks and support vector machines (SVM) for data classification. These schemes showed high performances with both training and test sets and many combinations of features (with a maximum accuracy of 96.67%). Additionally, there was a strong consideration for breathing frequency as a relevant feature in the HRV analysis