The novel idea of alloying,which is based on the utilization of multiple principal elements in high concentrations,has created a novel class of promising materials called high entropy alloys(HEAs).So far,several HEAs ...The novel idea of alloying,which is based on the utilization of multiple principal elements in high concentrations,has created a novel class of promising materials called high entropy alloys(HEAs).So far,several HEAs with outstanding properties beyond those of conventional alloys have been discovered,and new superior high-entropy alloys are still expected to be developed in the future.However,the fabrication process of HEAs through conventional manufacturing techniques suffers from significant limitations due to the intrinsic requirements of HEAs.Additive manufacturing(AM),on the other hand,has provided new opportunities for fabricating geometrically complex HEAs with the possibility of in situ tailoring of their microstructure features.Considering the growing interest in AM of HEAs during most recent years,this review article aims at providing the state of the art in AM of HEAs.It describes the feedstock requirements for laser based AM techniques.Thereafter,a comprehensive picture of the current state of nearly all HEAs processed by laser metal deposition(LMD),selective laser melting(SLM)and selective electron beam melting(SEBM)is presented.Special attention is paid to the features of AM derived microstructures along with their outstanding properties and underlying mechanisms for various material processing combinations.The AM of interstitial solute hardening HEAs,HEA matrix composites as well as non-beam based AM of HEAs will also be addressed.The post-AM treatments and the strategies to fabricate defect-free HEAs are summarized.Finally,a conclusion of current state and future prospects of additive manufacturing of HEAs will be presented.展开更多
This review describes current approaches to the management of patients with cirrhotic ascites in relation to the severity of its clinical manifestations. The PubMed database, the Google Scholar retrieval system, the C...This review describes current approaches to the management of patients with cirrhotic ascites in relation to the severity of its clinical manifestations. The PubMed database, the Google Scholar retrieval system, the Cochrane Database of Systematic Reviews, and the reference lists from related articles were used to search for relevant publications. Articles corresponding to the aim of the review were selected for 1991-2018 using the keywords:“liver cirrhosis,”“portal hypertension,”“ascites,”“pathogenesis,”“diagnostics,” and “treatment.” Uncomplicated and refractory ascites in patients with cirrhosis were the inclusion criteria. The literature analysis has shown that despite the achievements of modern hepatology, the presence of ascites is associated with poor prognosis and high mortality. The key to successful management of patients with ascites may be the stratification of the risk of an adverse outcome and personalized therapy. Pathogenetically based approach to the choice of pharmacotherapy and optimization of minimally invasive methods of treatment may improve the quality of life and increase the survival rate of this category of patients.展开更多
BACKGROUND Atherosclerotic cardiovascular disease(ASCVD)is the leading cause of mortality in patients with nonalcoholic fatty liver disease(NAFLD).Weight loss is a key factor for successful NAFLD and CVD therapy.Ursod...BACKGROUND Atherosclerotic cardiovascular disease(ASCVD)is the leading cause of mortality in patients with nonalcoholic fatty liver disease(NAFLD).Weight loss is a key factor for successful NAFLD and CVD therapy.Ursodeoxycholic acid(UDCA),which is one of the first-line therapeutic agents for treatment of NAFLD,is reported to have a beneficial effect on dyslipidemia and ASCVD risk because of antioxidant properties.AIM To evaluate the effects of 6 mo of UDCA treatment on hepatic function tests,lipid profile,hepatic steatosis and fibrosis,atherogenesis,and ASCVD risk in men and women with NAFLD,as well as to assess the impact of>5%weight reduction on these parameters.METHODS An open-label,multicenter,international noncomparative trial was carried out at primary health care settings and included 174 patients with ultrasound-diagnosed NAFLD who received 15 mg/kg/d UDCA for 6 mo and were prescribed lifestyle modification with diet and exercise.The efficacy criteria were liver enzymes,lipid profile,fatty liver index(FLI),noninvasive liver fibrosis tests(nonalcoholic fatty liver disease fibrosis score and liver fibrosis index),carotid intima-media thickness(CIMT),and ASCVD risk score.To test statistical hypotheses,the Wilcoxon test,paired t-test,Fisher’s exact test,and Pearson's chi-squared test were used.RESULTS The alanine aminotransferase(ALT)level changed by-14.1 U/L(-31.0;-5.3)from baseline to 3 mo and by-6.5 U/L(-14.0;0.1)from 3 to 6 mo.The magnitude of ALT,aspartate transaminase,and glutamyltransferase decrease was greater during the first 3 mo of treatment compared to the subsequent 3 mo(P<0.001,P<0.01,P<0.001,respectively).At 6 mo,in the total sample,we observed a statistically significant decrease in body weight and levels of FLI:84.9±10.4 vs 72.3±17.6,P<0.001,total cholesterol:6.03±1.36 vs 5.76±1.21,Р<0.001,lowdensity lipoprotein:3.86±1.01 vs 3.66±0.91,Р<0.001,and triglyceride:3.18(2.00;4.29)vs 2.04(1.40;3.16),Р<0.001.No effect on nonalcoholic fatty liver disease fibrosis score or liver fibrosis ind展开更多
The high entropy alloys(HEAs)are the newly developed high-performance materials that have gained significant importance in defence,nuclear and aerospace sector due to their superior mechanical properties,heat resistan...The high entropy alloys(HEAs)are the newly developed high-performance materials that have gained significant importance in defence,nuclear and aerospace sector due to their superior mechanical properties,heat resistance,high temperature strength and corrosion resistance.These alloys are manufactured by the equal mixing or larger proportions of five or more alloying elements.HEAs exhibit superior mechanical performance compared to traditional engineering alloys because of the extensive alloying composition and higher entropy of mixing.Solid state welding(SSW)techniques such as friction stir welding(FSW),rotary friction welding(RFW),diffusion bonding(DB)and explosive welding(EW)have been efficiently deployed for improving the microstructural integrity and mechanical properties of welded HEA joints.The HEA interlayers revealed greater potential in supressing the formation of deleterious intermetallic phases and maximizing the mechanical properties of HEAs joints.The similar and dissimilar joining of HEAs has been manifested to be viable for HEA systems which further expands their industrial applications.Thus,the main objective of this review paper is to present a critical review of current state of research,challenges and opportunities and main directions in SSW of HEAs mainly CoCrFeNiMn and Al_xCoCrFeNi alloys.The state of the art of problems,progress and future outlook in SSW of HEAs are critically reviewed by considering the formation of phases,microstructural evolution and mechanical properties of HEAs joints.展开更多
The paper discusses the advancements and applications of neural networks, specifically ChatGPT, in various fields, including chemistry education and research. It examines the benefits of AI and ChatGPT, such as their ...The paper discusses the advancements and applications of neural networks, specifically ChatGPT, in various fields, including chemistry education and research. It examines the benefits of AI and ChatGPT, such as their ability to process and analyze large amounts of data, create personalized training systems, and offer problem-solving recommendations. The paper delves into practical applications, showcasing how ChatGPT can be utilised to augment chemistry learning. It provides examples of using ChatGPT for creating tests, generating multiple-choice questions, and studying chemistry in general. Concerns are voiced about the ethical and societal impact of AI development. In conclusion, it explores the exciting potential of AI to tackle challenges that may exceed human capabilities alone, paving the way for further exploration and collaboration between humans and intelligent machines.展开更多
BACKGROUND An aneurysm of the left atrial appendage is one of the rare but potentially hazardous heart defects.The risk of lethal complications grows with its size.To date,about 150 cases of this defect have been desc...BACKGROUND An aneurysm of the left atrial appendage is one of the rare but potentially hazardous heart defects.The risk of lethal complications grows with its size.To date,about 150 cases of this defect have been described in the literature.We present a case of left atrial appendage aneurysm with the deformation of the mitral valve and the left main coronary and circumflex artery,which required mitral valve annuloplasty and bifurcation stenting.CASE SUMMARY A 58-year-old man presented to our hospital complaining of shortness of breath,general weakness,dizziness during physical exertion,and fatigue.Based on the results of echocardiography,an aneurysm of the left atrium was suspected.A free-breathing real-time cine magnetic resonance imaging with electrocardiograph synchronization confirmed the diagnosis of left atrial appendage aneurysm.The patient underwent an aneurysmectomy via a median sternotomy with cardiopulmonary bypass.Intraoperative transesophageal echocardiography revealed relative mitral insufficiency that was corrected with an annuloplasty ring.Intraoperative coronary angiogram showed impaired blood flow in the left main coronary and circumflex artery and 60%stenosis.For this reason,bifurcation stenting was performed.The patient had an uneventful postoperative clinical course and was discharged from the hospital on the 10th day in a satisfactory condition.CONCLUSION Left atrial appendage aneurysm is a rare and dangerous heart pathology that requires surgery to prevent related complications.展开更多
BACKGROUND Although early abdominal complications after coronary artery bypass grafting(CABG)with cardiopulmonary bypass(CPB)are rare,the associated mortality remains high.AIM To develop a risk score for the predictio...BACKGROUND Although early abdominal complications after coronary artery bypass grafting(CABG)with cardiopulmonary bypass(CPB)are rare,the associated mortality remains high.AIM To develop a risk score for the prediction of early abdominal complications after CABG with CPB.METHODS This retrospective study was performed in the Federal State Budgetary Establishment“Federal Center of Cardiovascular Surgery”of the Ministry of Health of Russia(the city of Chelyabinsk)and included data of 6586 patients who underwent CABG with CPB during 2011-2017.The risk factors taken for evaluation were compared between patients with early abdominal complications(n=73)and without them(n=6513).We identified the most important risk factors and their influence on the development of early abdominal complications after CABG with CPB.RESULTS Gender and the presence of postinfarction cardiosclerosis,chronic kidney disease,or diabetes in the anamnesis did not affect the occurrence of abdominal complications.The leading risk factors of the early abdominal complications after CABG with CPB were multifocal atherosclerosis,extracorporeal membrane oxygenation,intra-aortic balloon pump,atrial fibrillation,perioperative myocardial infarction,and the need for resternotomy in the postoperative period.The average value of the predicted probability was 0.087±0.015 in patients with early abdominal complications after CABG with CPB and 0.0094±0.0003 in patients without these complications.The percentage of correct classification turned out to be 98.9%.After calculating a score for each of the leading risk factors,we counted a total score for each particular patient.The highest risk was noted in patients with a total score of 7 or more.CONCLUSION The developed score predicts the risk of early abdominal complications after CABG with CPB and makes it possible to stratify patients by risk groups.展开更多
The paper presents the key milestones and outcomes of 65-year studies of the carcinogenic consequences of accidental radiation exposure of the population of the Ural region.The radioactive contamination of the Techa R...The paper presents the key milestones and outcomes of 65-year studies of the carcinogenic consequences of accidental radiation exposure of the population of the Ural region.The radioactive contamination of the Techa River and the 1957 accident at the Mayak Production Association were the reasons of the long-term population exposure at a wide dose-range.The most important tasks of the study were the reconstruction of individual doses,follow-up of the solid cancer and leukemia incidence and mortality among cohort members.The research results have shown that chronic human exposure,in comparison to acute exposure,does not reduce the risk of developing malignant tumors and leukemias.The value of the dose-rate factor does not exceed"one".Thus,according to our data,the Publication 103 of the International Commission on Radiological Protection seemed to underestimate the radiation risk of malignant tumors and leukemias in case of low dose-rate exposure of the population by a factor of two.Prospects for further radio-epidemiological studies in the Urals are associated with the analysis of the cohort of Southern Urals Populations Exposed to Radiation,which includes about 63 thousand exposed people and makes it possible to assess the radiation risk of solid cancers of certain localizations,certain types of leukemia,and non-cancer effects.展开更多
Objective To assess the risk of lens opacity depending on the dose in the population exposed to external and internal radiation for a long time,based on a long-term clinical follow-up of the cohorts of people exposed ...Objective To assess the risk of lens opacity depending on the dose in the population exposed to external and internal radiation for a long time,based on a long-term clinical follow-up of the cohorts of people exposed to radiation as a result of two radiation accidents in the South Urals.Methods A layer-by-layer morphological study of the lens of 1,377 exposed individuals was conducted according to a special program in the Clinical Department of the Urals Research Center for Radiation Medicine(URCRM)68 years after the onset of exposure.Lens changes were classified in accordance with the lens opacities classification(LOCS)III and included images of lens.To calculate the doses to lens,the data were taken into account,including the person's residence history in the radioactively contaminated territory,age and sex that affected their lifestyle and diet,radionuclide distribution in organs and tissues.Individualized lens doses were calculated using Techa River Dosimetry System(TRDS)-2016.Case-control method was used for statistical analysis.Results Individual values of absorbed dose to lens ranged from 0 to 600mGy.A dose-dependent increased risk of posterior subcapsular cataract(PSC)(OR1.54,95%CI:1.04–2.27)and nuclear cataract(OR1.84,95%CI:1.14–2.95)was found among chronically exposed individuals by a case-control method.No evidence of dose effect was found for cortical cataracts.Conclusions The results showed that population exposed to long-term chronic low-dose radiation was subjected to an increased risk of PSC and nuclear cataract development.展开更多
The uniaxial compressive strength(UCS)of rock is an essential property of rock material in different relevant applications,such as rock slope,tunnel construction,and foundation.It takes enormous time and effort to obt...The uniaxial compressive strength(UCS)of rock is an essential property of rock material in different relevant applications,such as rock slope,tunnel construction,and foundation.It takes enormous time and effort to obtain the UCS values directly in the laboratory.Accordingly,an indirect determination of UCS through conducting several rock index tests that are easy and fast to carry out is of interest and importance.This study presents powerful boosting trees evaluation framework,i.e.,adaptive boosting machine,extreme gradient boosting machine(XGBoost),and category gradient boosting machine,for estimating the UCS of sandstone.Schmidt hammer rebound number,P-wave velocity,and point load index were chosen as considered factors to forecast UCS values of sandstone samples.Taylor diagrams and five regression metrics,including coefficient of determination(R2),root mean square error,mean absolute error,variance account for,and A-20 index,were used to evaluate and compare the performance of these boosting trees.The results showed that the proposed boosting trees are able to provide a high level of prediction capacity for the prepared database.In particular,itwas worth noting that XGBoost is the best model to predict sandstone strength and it achieved 0.999 training R^(2) and 0.958 testing R^(2).The proposed model had more outstanding capability than neural network with optimization techniques during training and testing phases.The performed variable importance analysis reveals that the point load index has a significant influence on predicting UCS of sandstone.展开更多
In this paper,we report on the crystal structure and magnetic properties of the nano structured Baordered phases of rare-earth manganites obtained from the optimally doped solid solutions Ln0.70Ba0.30MnO3(Ln=Pr,Nd).Th...In this paper,we report on the crystal structure and magnetic properties of the nano structured Baordered phases of rare-earth manganites obtained from the optimally doped solid solutions Ln0.70Ba0.30MnO3(Ln=Pr,Nd).The materials were studied by X-ray diffraction,scanning electron microscopy,energy dispersive spectroscopy and SQUID-magnetometry techniques.It is found that states with different degrees of cation ordering in the A-sublattice of the ABO3 perovskite can be obtained by employing special conditions of chemical treatment.In particular,reduction of the parent compounds results in the formation of a nanocomposite containing ferrimagnetic anion-deficient ordered phase LnBaMn2O5.Oxidation of the composite does not change an average size of the nanocrystallites,but drastically alters their phase composition to stabilize ferromagnetic stoichiometric ordered phase LnBaMn2O6 and ferromagnetic superstoichiometric disordered phase Ln0.90Ba0.10MnO3+δ.It is shown that the magnetic properties of the materials are determined by the joint action of chemical(cation ordering)and external(surface tension)pressures.展开更多
The article presents the results of the experimental study that was devoted to determining the blocking influence of the solar microwave radiation on the process of biofilm formation in Gram-positive and Gram-negative...The article presents the results of the experimental study that was devoted to determining the blocking influence of the solar microwave radiation on the process of biofilm formation in Gram-positive and Gram-negative microorganisms. The microwave generator that allows simulating microwave “splashes” of the Sun in the frequency range (4.0 - 4.3 GHz) with the controlled intensity of radiation (from 50 μW/sm2 to 500 μW/sm2) was used for conducting this research. It is found out that the simulated solar radiation of the microwave range blocks the formation of the extracellular matrix by the opportunistic microorganisms. The results of this study confirm the hypothesis of the evolutionary nature of the leading role of the microwave radiation of the Sun in the life processes of organisms. The technology of the exposure on the microorganisms that was used in the experiment opens up the real prospects for reducing the persistent potential of microorganisms and improving the efficiency of the bacterial infections treatment.展开更多
We have compared 142 adult men and women of various ages, grouped by professional occupation, all the occupations involving local muscular performance. We studied heart reactions and central nervous system reactions t...We have compared 142 adult men and women of various ages, grouped by professional occupation, all the occupations involving local muscular performance. We studied heart reactions and central nervous system reactions to local muscular performance done until fatigue set in. The results suggested that adaptive body changes had a number of shared signs, namely, tachycardia, hypertension, and increased statistical figures of the heart rhythm, which were indicative of tension in central regulatory mechanisms of the heart.展开更多
Some experiments on radiation of hydrocarbons and the alloys including Bismuth and Lead by power nanosecond electromagnetic pulses are described. The list of the used equipment and technique of experiments are given. ...Some experiments on radiation of hydrocarbons and the alloys including Bismuth and Lead by power nanosecond electromagnetic pulses are described. The list of the used equipment and technique of experiments are given. The result of these experiences is change of a chemical composition of the irradiated samples in comparison with the initial ones. Conversion of part of Bismuth to Lead is observed. The hypothesis of such changes is made.展开更多
The paper highlights the problem of training of interpreters in the system of continuing education in Russia. The theoretical analysis of the essence and structure of the information competency of an interpreter in co...The paper highlights the problem of training of interpreters in the system of continuing education in Russia. The theoretical analysis of the essence and structure of the information competency of an interpreter in continuing education as subjects is proposed. The research techniques were document analysis, interviews, participant observation, work process analysis, and focus groups. This paper presents a brief overview of the information competency of an interpreter. The importance of the information competency in the structure of professional competency of an interpreter is acknowledged by the majority of modern experts. But there still exists the problem of determining the set of skills which present the information competency of an interpreter. This paper introduces the author＇s view on the problem of defining the essence and structure of the information competency of an interpreter.展开更多
The properties of synthetic graphite materials, widely used in advanced fields, are determined by their structure, which is formed in the process of high-temperature (~2500<span style="white-space:normal;"...The properties of synthetic graphite materials, widely used in advanced fields, are determined by their structure, which is formed in the process of high-temperature (~2500<span style="white-space:normal;"><span style="white-space:nowrap;">°</span></span><span style="white-space:normal;"></span>C) heat treatment. The fine structure of a graphitizing carbon material based on petroleum coke containing 1.3 wt% S at various stages of graphitization was studied by X-ray diffraction analysis. Some of the samples contained the addition of dispersed Fe<sub>2</sub>O<sub>3</sub>. It is shown that the heat-treated material in the range 1200<span style="white-space:normal;"><span style="white-space:nowrap;">°</span></span><span style="white-space:normal;"></span>C - 2600<span style="white-space:normal;"><span style="white-space:nowrap;">°</span></span><span style="white-space:normal;"></span>C is heterogeneous, its component composition is determined by the processing temperature and the presence of Fe<sub>2</sub>O<sub>3</sub> additive. The observed dependence of the component composition on the heat treatment temperature suggests that the process of graphitization of the carbon material, apparently, develops through a number of metastable states.展开更多
The influence of two-stage isothermal treatment on the change in the linear dimensions of the fiber, the average sizes of the coherent scattering regions, the texture and phase composition of the polyacrylonitrile fib...The influence of two-stage isothermal treatment on the change in the linear dimensions of the fiber, the average sizes of the coherent scattering regions, the texture and phase composition of the polyacrylonitrile fiber in the process of isothermal thermal stabilization is considered by the methods of dilatometry and X-ray diffraction analysis. It is shown that preliminary short-term heat treatment at a lower temperature affects the process of structural transformations of the polyacrylonitrile fiber material and the formation of a new highly dispersed phase of the thermally stabilized fiber.展开更多
In the present article, we give a variant of the theory of gravity, which distinguishes between particles and antiparticles. In this theory that called two-signed gravity, in contrast to Einstein’s gravity, contribut...In the present article, we give a variant of the theory of gravity, which distinguishes between particles and antiparticles. In this theory that called two-signed gravity, in contrast to Einstein’s gravity, contributions from particles and antiparticles in the tensor, which are the source of the gravitational field are taken with different signs. In two-sign gravity, antiattraction exists between particles and antiparticles. In the framework of two-signed gravitation, it is naturally assume that Universe is not only electroneutral, but also gravitationally neutral too. In present paper, we suggest model of homogeneous, isotropic, uniformly expanding Universe. It is shown, what within framework of that model, which does not contain any free parameters, well explained observed dynamics of the Universe.展开更多
In the framework of the theory of the gravitational field, which distinguishes between particles and antiparticles, it is shown that even in the Early Universe its disintegration occurred into areas consisting of bary...In the framework of the theory of the gravitational field, which distinguishes between particles and antiparticles, it is shown that even in the Early Universe its disintegration occurred into areas consisting of baryons (worlds), and areas consisting of antibaryons (antiworlds). It is hypothesized that astronomers have observed worlds and antiworlds for fifteen years. They are, according to the authors, objects that can be seen as relatively bright spots against the almost uniform background of cosmic microwave radiation, having a characteristic angular size of quarter degree.展开更多
基金the Ministry of Science and Higher Education of the Russian Federation as part of the Project(No.FENU-2020-0020)。
文摘The novel idea of alloying,which is based on the utilization of multiple principal elements in high concentrations,has created a novel class of promising materials called high entropy alloys(HEAs).So far,several HEAs with outstanding properties beyond those of conventional alloys have been discovered,and new superior high-entropy alloys are still expected to be developed in the future.However,the fabrication process of HEAs through conventional manufacturing techniques suffers from significant limitations due to the intrinsic requirements of HEAs.Additive manufacturing(AM),on the other hand,has provided new opportunities for fabricating geometrically complex HEAs with the possibility of in situ tailoring of their microstructure features.Considering the growing interest in AM of HEAs during most recent years,this review article aims at providing the state of the art in AM of HEAs.It describes the feedstock requirements for laser based AM techniques.Thereafter,a comprehensive picture of the current state of nearly all HEAs processed by laser metal deposition(LMD),selective laser melting(SLM)and selective electron beam melting(SEBM)is presented.Special attention is paid to the features of AM derived microstructures along with their outstanding properties and underlying mechanisms for various material processing combinations.The AM of interstitial solute hardening HEAs,HEA matrix composites as well as non-beam based AM of HEAs will also be addressed.The post-AM treatments and the strategies to fabricate defect-free HEAs are summarized.Finally,a conclusion of current state and future prospects of additive manufacturing of HEAs will be presented.
文摘This review describes current approaches to the management of patients with cirrhotic ascites in relation to the severity of its clinical manifestations. The PubMed database, the Google Scholar retrieval system, the Cochrane Database of Systematic Reviews, and the reference lists from related articles were used to search for relevant publications. Articles corresponding to the aim of the review were selected for 1991-2018 using the keywords:“liver cirrhosis,”“portal hypertension,”“ascites,”“pathogenesis,”“diagnostics,” and “treatment.” Uncomplicated and refractory ascites in patients with cirrhosis were the inclusion criteria. The literature analysis has shown that despite the achievements of modern hepatology, the presence of ascites is associated with poor prognosis and high mortality. The key to successful management of patients with ascites may be the stratification of the risk of an adverse outcome and personalized therapy. Pathogenetically based approach to the choice of pharmacotherapy and optimization of minimally invasive methods of treatment may improve the quality of life and increase the survival rate of this category of patients.
文摘BACKGROUND Atherosclerotic cardiovascular disease(ASCVD)is the leading cause of mortality in patients with nonalcoholic fatty liver disease(NAFLD).Weight loss is a key factor for successful NAFLD and CVD therapy.Ursodeoxycholic acid(UDCA),which is one of the first-line therapeutic agents for treatment of NAFLD,is reported to have a beneficial effect on dyslipidemia and ASCVD risk because of antioxidant properties.AIM To evaluate the effects of 6 mo of UDCA treatment on hepatic function tests,lipid profile,hepatic steatosis and fibrosis,atherogenesis,and ASCVD risk in men and women with NAFLD,as well as to assess the impact of>5%weight reduction on these parameters.METHODS An open-label,multicenter,international noncomparative trial was carried out at primary health care settings and included 174 patients with ultrasound-diagnosed NAFLD who received 15 mg/kg/d UDCA for 6 mo and were prescribed lifestyle modification with diet and exercise.The efficacy criteria were liver enzymes,lipid profile,fatty liver index(FLI),noninvasive liver fibrosis tests(nonalcoholic fatty liver disease fibrosis score and liver fibrosis index),carotid intima-media thickness(CIMT),and ASCVD risk score.To test statistical hypotheses,the Wilcoxon test,paired t-test,Fisher’s exact test,and Pearson's chi-squared test were used.RESULTS The alanine aminotransferase(ALT)level changed by-14.1 U/L(-31.0;-5.3)from baseline to 3 mo and by-6.5 U/L(-14.0;0.1)from 3 to 6 mo.The magnitude of ALT,aspartate transaminase,and glutamyltransferase decrease was greater during the first 3 mo of treatment compared to the subsequent 3 mo(P<0.001,P<0.01,P<0.001,respectively).At 6 mo,in the total sample,we observed a statistically significant decrease in body weight and levels of FLI:84.9±10.4 vs 72.3±17.6,P<0.001,total cholesterol:6.03±1.36 vs 5.76±1.21,Р<0.001,lowdensity lipoprotein:3.86±1.01 vs 3.66±0.91,Р<0.001,and triglyceride:3.18(2.00;4.29)vs 2.04(1.40;3.16),Р<0.001.No effect on nonalcoholic fatty liver disease fibrosis score or liver fibrosis ind
基金financially supported by Ministry of Science and Higher Education of the Russian Federation(Grant No.FENU-2023-0013)。
文摘The high entropy alloys(HEAs)are the newly developed high-performance materials that have gained significant importance in defence,nuclear and aerospace sector due to their superior mechanical properties,heat resistance,high temperature strength and corrosion resistance.These alloys are manufactured by the equal mixing or larger proportions of five or more alloying elements.HEAs exhibit superior mechanical performance compared to traditional engineering alloys because of the extensive alloying composition and higher entropy of mixing.Solid state welding(SSW)techniques such as friction stir welding(FSW),rotary friction welding(RFW),diffusion bonding(DB)and explosive welding(EW)have been efficiently deployed for improving the microstructural integrity and mechanical properties of welded HEA joints.The HEA interlayers revealed greater potential in supressing the formation of deleterious intermetallic phases and maximizing the mechanical properties of HEAs joints.The similar and dissimilar joining of HEAs has been manifested to be viable for HEA systems which further expands their industrial applications.Thus,the main objective of this review paper is to present a critical review of current state of research,challenges and opportunities and main directions in SSW of HEAs mainly CoCrFeNiMn and Al_xCoCrFeNi alloys.The state of the art of problems,progress and future outlook in SSW of HEAs are critically reviewed by considering the formation of phases,microstructural evolution and mechanical properties of HEAs joints.
文摘The paper discusses the advancements and applications of neural networks, specifically ChatGPT, in various fields, including chemistry education and research. It examines the benefits of AI and ChatGPT, such as their ability to process and analyze large amounts of data, create personalized training systems, and offer problem-solving recommendations. The paper delves into practical applications, showcasing how ChatGPT can be utilised to augment chemistry learning. It provides examples of using ChatGPT for creating tests, generating multiple-choice questions, and studying chemistry in general. Concerns are voiced about the ethical and societal impact of AI development. In conclusion, it explores the exciting potential of AI to tackle challenges that may exceed human capabilities alone, paving the way for further exploration and collaboration between humans and intelligent machines.
文摘BACKGROUND An aneurysm of the left atrial appendage is one of the rare but potentially hazardous heart defects.The risk of lethal complications grows with its size.To date,about 150 cases of this defect have been described in the literature.We present a case of left atrial appendage aneurysm with the deformation of the mitral valve and the left main coronary and circumflex artery,which required mitral valve annuloplasty and bifurcation stenting.CASE SUMMARY A 58-year-old man presented to our hospital complaining of shortness of breath,general weakness,dizziness during physical exertion,and fatigue.Based on the results of echocardiography,an aneurysm of the left atrium was suspected.A free-breathing real-time cine magnetic resonance imaging with electrocardiograph synchronization confirmed the diagnosis of left atrial appendage aneurysm.The patient underwent an aneurysmectomy via a median sternotomy with cardiopulmonary bypass.Intraoperative transesophageal echocardiography revealed relative mitral insufficiency that was corrected with an annuloplasty ring.Intraoperative coronary angiogram showed impaired blood flow in the left main coronary and circumflex artery and 60%stenosis.For this reason,bifurcation stenting was performed.The patient had an uneventful postoperative clinical course and was discharged from the hospital on the 10th day in a satisfactory condition.CONCLUSION Left atrial appendage aneurysm is a rare and dangerous heart pathology that requires surgery to prevent related complications.
文摘BACKGROUND Although early abdominal complications after coronary artery bypass grafting(CABG)with cardiopulmonary bypass(CPB)are rare,the associated mortality remains high.AIM To develop a risk score for the prediction of early abdominal complications after CABG with CPB.METHODS This retrospective study was performed in the Federal State Budgetary Establishment“Federal Center of Cardiovascular Surgery”of the Ministry of Health of Russia(the city of Chelyabinsk)and included data of 6586 patients who underwent CABG with CPB during 2011-2017.The risk factors taken for evaluation were compared between patients with early abdominal complications(n=73)and without them(n=6513).We identified the most important risk factors and their influence on the development of early abdominal complications after CABG with CPB.RESULTS Gender and the presence of postinfarction cardiosclerosis,chronic kidney disease,or diabetes in the anamnesis did not affect the occurrence of abdominal complications.The leading risk factors of the early abdominal complications after CABG with CPB were multifocal atherosclerosis,extracorporeal membrane oxygenation,intra-aortic balloon pump,atrial fibrillation,perioperative myocardial infarction,and the need for resternotomy in the postoperative period.The average value of the predicted probability was 0.087±0.015 in patients with early abdominal complications after CABG with CPB and 0.0094±0.0003 in patients without these complications.The percentage of correct classification turned out to be 98.9%.After calculating a score for each of the leading risk factors,we counted a total score for each particular patient.The highest risk was noted in patients with a total score of 7 or more.CONCLUSION The developed score predicts the risk of early abdominal complications after CABG with CPB and makes it possible to stratify patients by risk groups.
文摘The paper presents the key milestones and outcomes of 65-year studies of the carcinogenic consequences of accidental radiation exposure of the population of the Ural region.The radioactive contamination of the Techa River and the 1957 accident at the Mayak Production Association were the reasons of the long-term population exposure at a wide dose-range.The most important tasks of the study were the reconstruction of individual doses,follow-up of the solid cancer and leukemia incidence and mortality among cohort members.The research results have shown that chronic human exposure,in comparison to acute exposure,does not reduce the risk of developing malignant tumors and leukemias.The value of the dose-rate factor does not exceed"one".Thus,according to our data,the Publication 103 of the International Commission on Radiological Protection seemed to underestimate the radiation risk of malignant tumors and leukemias in case of low dose-rate exposure of the population by a factor of two.Prospects for further radio-epidemiological studies in the Urals are associated with the analysis of the cohort of Southern Urals Populations Exposed to Radiation,which includes about 63 thousand exposed people and makes it possible to assess the radiation risk of solid cancers of certain localizations,certain types of leukemia,and non-cancer effects.
基金The performed studies have been supported by the Federal Medical Biological Agency.
文摘Objective To assess the risk of lens opacity depending on the dose in the population exposed to external and internal radiation for a long time,based on a long-term clinical follow-up of the cohorts of people exposed to radiation as a result of two radiation accidents in the South Urals.Methods A layer-by-layer morphological study of the lens of 1,377 exposed individuals was conducted according to a special program in the Clinical Department of the Urals Research Center for Radiation Medicine(URCRM)68 years after the onset of exposure.Lens changes were classified in accordance with the lens opacities classification(LOCS)III and included images of lens.To calculate the doses to lens,the data were taken into account,including the person's residence history in the radioactively contaminated territory,age and sex that affected their lifestyle and diet,radionuclide distribution in organs and tissues.Individualized lens doses were calculated using Techa River Dosimetry System(TRDS)-2016.Case-control method was used for statistical analysis.Results Individual values of absorbed dose to lens ranged from 0 to 600mGy.A dose-dependent increased risk of posterior subcapsular cataract(PSC)(OR1.54,95%CI:1.04–2.27)and nuclear cataract(OR1.84,95%CI:1.14–2.95)was found among chronically exposed individuals by a case-control method.No evidence of dose effect was found for cortical cataracts.Conclusions The results showed that population exposed to long-term chronic low-dose radiation was subjected to an increased risk of PSC and nuclear cataract development.
基金funded by Act 211 Government of the Russian Federation,Contract No.02.A03.21.0011.
文摘The uniaxial compressive strength(UCS)of rock is an essential property of rock material in different relevant applications,such as rock slope,tunnel construction,and foundation.It takes enormous time and effort to obtain the UCS values directly in the laboratory.Accordingly,an indirect determination of UCS through conducting several rock index tests that are easy and fast to carry out is of interest and importance.This study presents powerful boosting trees evaluation framework,i.e.,adaptive boosting machine,extreme gradient boosting machine(XGBoost),and category gradient boosting machine,for estimating the UCS of sandstone.Schmidt hammer rebound number,P-wave velocity,and point load index were chosen as considered factors to forecast UCS values of sandstone samples.Taylor diagrams and five regression metrics,including coefficient of determination(R2),root mean square error,mean absolute error,variance account for,and A-20 index,were used to evaluate and compare the performance of these boosting trees.The results showed that the proposed boosting trees are able to provide a high level of prediction capacity for the prepared database.In particular,itwas worth noting that XGBoost is the best model to predict sandstone strength and it achieved 0.999 training R^(2) and 0.958 testing R^(2).The proposed model had more outstanding capability than neural network with optimization techniques during training and testing phases.The performed variable importance analysis reveals that the point load index has a significant influence on predicting UCS of sandstone.
基金Project supported by the European Union’s Horizon 2020Research and Innovation Programme under the Marie Sklodowska-Curie grant agreement(778070)
文摘In this paper,we report on the crystal structure and magnetic properties of the nano structured Baordered phases of rare-earth manganites obtained from the optimally doped solid solutions Ln0.70Ba0.30MnO3(Ln=Pr,Nd).The materials were studied by X-ray diffraction,scanning electron microscopy,energy dispersive spectroscopy and SQUID-magnetometry techniques.It is found that states with different degrees of cation ordering in the A-sublattice of the ABO3 perovskite can be obtained by employing special conditions of chemical treatment.In particular,reduction of the parent compounds results in the formation of a nanocomposite containing ferrimagnetic anion-deficient ordered phase LnBaMn2O5.Oxidation of the composite does not change an average size of the nanocrystallites,but drastically alters their phase composition to stabilize ferromagnetic stoichiometric ordered phase LnBaMn2O6 and ferromagnetic superstoichiometric disordered phase Ln0.90Ba0.10MnO3+δ.It is shown that the magnetic properties of the materials are determined by the joint action of chemical(cation ordering)and external(surface tension)pressures.
文摘The article presents the results of the experimental study that was devoted to determining the blocking influence of the solar microwave radiation on the process of biofilm formation in Gram-positive and Gram-negative microorganisms. The microwave generator that allows simulating microwave “splashes” of the Sun in the frequency range (4.0 - 4.3 GHz) with the controlled intensity of radiation (from 50 μW/sm2 to 500 μW/sm2) was used for conducting this research. It is found out that the simulated solar radiation of the microwave range blocks the formation of the extracellular matrix by the opportunistic microorganisms. The results of this study confirm the hypothesis of the evolutionary nature of the leading role of the microwave radiation of the Sun in the life processes of organisms. The technology of the exposure on the microorganisms that was used in the experiment opens up the real prospects for reducing the persistent potential of microorganisms and improving the efficiency of the bacterial infections treatment.
文摘We have compared 142 adult men and women of various ages, grouped by professional occupation, all the occupations involving local muscular performance. We studied heart reactions and central nervous system reactions to local muscular performance done until fatigue set in. The results suggested that adaptive body changes had a number of shared signs, namely, tachycardia, hypertension, and increased statistical figures of the heart rhythm, which were indicative of tension in central regulatory mechanisms of the heart.
文摘Some experiments on radiation of hydrocarbons and the alloys including Bismuth and Lead by power nanosecond electromagnetic pulses are described. The list of the used equipment and technique of experiments are given. The result of these experiences is change of a chemical composition of the irradiated samples in comparison with the initial ones. Conversion of part of Bismuth to Lead is observed. The hypothesis of such changes is made.
文摘The paper highlights the problem of training of interpreters in the system of continuing education in Russia. The theoretical analysis of the essence and structure of the information competency of an interpreter in continuing education as subjects is proposed. The research techniques were document analysis, interviews, participant observation, work process analysis, and focus groups. This paper presents a brief overview of the information competency of an interpreter. The importance of the information competency in the structure of professional competency of an interpreter is acknowledged by the majority of modern experts. But there still exists the problem of determining the set of skills which present the information competency of an interpreter. This paper introduces the author＇s view on the problem of defining the essence and structure of the information competency of an interpreter.
文摘The properties of synthetic graphite materials, widely used in advanced fields, are determined by their structure, which is formed in the process of high-temperature (~2500<span style="white-space:normal;"><span style="white-space:nowrap;">°</span></span><span style="white-space:normal;"></span>C) heat treatment. The fine structure of a graphitizing carbon material based on petroleum coke containing 1.3 wt% S at various stages of graphitization was studied by X-ray diffraction analysis. Some of the samples contained the addition of dispersed Fe<sub>2</sub>O<sub>3</sub>. It is shown that the heat-treated material in the range 1200<span style="white-space:normal;"><span style="white-space:nowrap;">°</span></span><span style="white-space:normal;"></span>C - 2600<span style="white-space:normal;"><span style="white-space:nowrap;">°</span></span><span style="white-space:normal;"></span>C is heterogeneous, its component composition is determined by the processing temperature and the presence of Fe<sub>2</sub>O<sub>3</sub> additive. The observed dependence of the component composition on the heat treatment temperature suggests that the process of graphitization of the carbon material, apparently, develops through a number of metastable states.
文摘The influence of two-stage isothermal treatment on the change in the linear dimensions of the fiber, the average sizes of the coherent scattering regions, the texture and phase composition of the polyacrylonitrile fiber in the process of isothermal thermal stabilization is considered by the methods of dilatometry and X-ray diffraction analysis. It is shown that preliminary short-term heat treatment at a lower temperature affects the process of structural transformations of the polyacrylonitrile fiber material and the formation of a new highly dispersed phase of the thermally stabilized fiber.
文摘In the present article, we give a variant of the theory of gravity, which distinguishes between particles and antiparticles. In this theory that called two-signed gravity, in contrast to Einstein’s gravity, contributions from particles and antiparticles in the tensor, which are the source of the gravitational field are taken with different signs. In two-sign gravity, antiattraction exists between particles and antiparticles. In the framework of two-signed gravitation, it is naturally assume that Universe is not only electroneutral, but also gravitationally neutral too. In present paper, we suggest model of homogeneous, isotropic, uniformly expanding Universe. It is shown, what within framework of that model, which does not contain any free parameters, well explained observed dynamics of the Universe.
文摘In the framework of the theory of the gravitational field, which distinguishes between particles and antiparticles, it is shown that even in the Early Universe its disintegration occurred into areas consisting of baryons (worlds), and areas consisting of antibaryons (antiworlds). It is hypothesized that astronomers have observed worlds and antiworlds for fifteen years. They are, according to the authors, objects that can be seen as relatively bright spots against the almost uniform background of cosmic microwave radiation, having a characteristic angular size of quarter degree.
