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Chronic hepatitis C virus infection:Prevalence of extrahepatic manifestations and association with cryoglobulinemia in Bulgarian patients

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World Journal of Gastroenterology 2007年第48期13卷 6518-6528页

作者： Diana V Stefanova-Petrova Anelia H Tzvetanska Elisaveta J Naumova Anastasia P Mihailova evgenii a hadjiev Rumiana P Dikova Mircho I Vukov Konstantin G Tchernev Department of Internal Diseases and Gastroenterology University Hospital Alexandrovska Viral Laboratory University Pediatric Hospital Central Laboratory of Immunology University Hospital Alexandrovska Department of Hematology University Hospital Alexandrovska Department of Pathology University Hospital Alexandrovka National Centre for Health Information

AIM: To assess the prevalence of extrahepatic manifestations in Bulgarian patients with chronic hepatitis C virus (HCV) infection and identify the clinical and biological manifestations associated with cryoglobulinemia. METHODS: The medical records of 136 chronically infected HCV patients were reviewed to assess the prevalence of extrahepatic manifestations. Association between cryoglobulin-positivity and other manifestations were identified using χ2 and Fisher’s exact test. Risk factors for the presence of extrahepatic manifestations were assessed by logistic regression analysis. RESULTS: Seventy six percent (104/136) of the patients had at least one extrahepatic manifestation. Clinical manifestations included fatigue (59.6%), kidney impairment (25.0%), type 2 diabetes (22.8%), paresthesia (19.9%), arthralgia (18.4%), palpable purpura (17.6%), lymphadenopathy (16.2%), pulmonary fi brosis (15.4%), thyroid dysfunction (14.7%), Raynaud’s phenomenon (11.8%), B-cell lymphoma (8.8%), sicca syndrome (6.6%), and lichen planus (5.9%). The biological manifestations included cryoglobulinproduction (37.5%), thrombocytopenia (31.6%), and autoantibodies: anti-nuclear (18.4%), anti-smooth muscle (16.9%), anti-neutrophil cytoplasm (13.2%) and anti-cardiolipin (8.8%). All extrahepatic manifestations showed an association with cryoglobulin-positivity, with the exception of thyroid dysfunction, sicca syndrome, and lichen planus. Risks factors for the presence of extrahepatic manifestations (univariate analysis) were: age ≥ 60 years, female gender, virus transmission by blood transfusions, longstanding infection (≥ 20 years), and extensive liver fi brosis. The most signifi cant risks factors (multivariate analysis) were longstanding infection and extensive liver fi brosis. CONCLUSION: We observed a high prevalence of extrahepatic manifestations in patients with chronic HCV infection. Most of these manifestations were associated with impaired lymphoproliferation and cryoglobulin produc

关键词： Hepatitis C Liver cirrhosis Extrahepatic manifestations

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Boosting propane dehydrogenation by gallium hydride species formed in situ

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Science China Chemistry 2024年第6期67卷 1753-1755页

作者： evgenii V.Kondratenko Leibniz-Institut für Katalyse e.V. Albert-Einstein-Str.29aRostock18059Germany

An inspiring paper recently published in Nature Chemistry[1]by the group of *** Gong at Tianjin University is the motivation for this highlight *** reported results show that the understanding of reaction-induced restructuring of heterogeneous catalysts is of great importance for their targeted development because usually unstable compounds can be formed and stabilized under reaction conditions.

关键词： conditions hydride stabilized

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Light olefins synthesis from C1-C2 paraffins via oxychlorination processes

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Frontiers of Chemical Science and Engineering 2013年第3期7卷 279-288页

作者： Anton SHALYGIN evgenii PAUKSHTIS evgenii KOVALYOV Bair BAL'ZHINIMAEV Boreskov Institute of Catalysis Novosibirsk 630090 Russia

A two-step process was employed to convert methane or ethane to light olefins via the formation of an intermediate monoalkyl halide. A novel K4RuOCll0/TiO2 catalyst was tested for the oxidative chlorination of methane and ethane. The catalyst had high selectivity for methyl and ethyl chlorides, 80% and 90%, respectively. During the oxychlorination of ethane at T〉~250~C, the formation of ethylene as a reaction product along with ethyl chloride was observed. In situ Fourier transform infrared studies showed that the key intermediate for monoalkyl chloride and ethylene formation is the alkoxy group. The reaction mechanism for the oxidative chlorina- tion of methane and ethane over the Ru-oxychloride catalyst was proposed. The novel fiber glass catalyst was also tested for the dehydrochlorination of alkyl chlorides to ethylene and propylene. Very high selectivities （up to 94%-98%） for ethylene and propylene formation as well as high stability were demonstrated.

关键词： oxychlorination methane ethane light olefins ruthenium catalyst

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Nonlinear Young’s Modulus of New Red Sandstone:Experimental Studies

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Acta Mechanica Solida Sinica 2021年第6期34卷 989-999页

作者： evgenii Riabokon Vladimir Poplygin Mikhail Turbakov evgenii Kozhevnikov Dmitrii Kobiakov Mikhail Guzev Marian Wiercigroch Centre for Applied Dynamics Research School of EngineeringUniversity of AberdeenAberdeenUK Department of Oil and Gas Technologies Perm National Research Polytechnic UniversityPermRussia Institute of Applied Mathematics Far Eastern Branch of the Russian Academy of SciencesVladivostokRussia

Young’s modulus of New Red Sandstone was investigated experimentally to gain insight into its nonlinear nature.A large experimental programme was carried out by applying a controllable quasi-static and dynamic uniaxial loading to 286 dry sandstone samples of four different *** static and dynamic tests,similar to those aiming at determining the uniaxial compressive strength,were conducted using the state-of-the-art experimental facilities at the University of Aberdeen including a custom-built small experimental rig for inducing a dynamic uniaxial compressive load via a piezoelectric *** obtained results have confirmed a complex nature of Young’s modulus of ***,under a harmonic dynamic loading,it shows strongly nonlinear behaviour,which is hardening and softening with respect to frequency and amplitude of the dynamic loading,respectively.

关键词： Sandstone Young’s modulus Static and dynamic loading Experiments Stress and strain Nonlinearity

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Assessment of the Elastic-Wave Well Treatment in Oil-Bearing Clastic and Carbonate Reservoirs

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Fluid Dynamics & Materials Processing 2023年第6期19卷 1495-1505页

作者： Vladimir Poplygin Chengzhi Qi Mikhail Guzev evgenii Kozhevnikov Artem Kunitskikh evgenii Riabokon Mikhail Turbakov Perm National Research Polytechnic University Perm614990Russian Beijing University of Civil Engineering and Architecture Beijing100049China Institute for Applied Mathematics FEB RAS Vladivostok690041Russian

A set of techniques for well treatment aimed to enhance oil recovery are considered in the present *** are based on the application of elastic waves of various types(dilation-wave,vibro-wave,or other acoustically induced effects).In such a context,a new technique is proposed to predict the effectiveness of the elastic-wave well treatment using the rank distribution according to Zipf’s *** is revealed that,when the results of elastic wave well treatments are analyzed,groups of wells exploiting various geological deposits can differ in terms of their slope coefficients and free *** the slope coefficient increases,the average increase in the well oil production rate(after the well treatment)becomes *** equation is obtained accordingly for estimating the slope coefficient in the Zipf’s equation from the frequency of the elastic *** obtained results demonstrate the applicability of the Zipf’s law in the analysis of the technological efficiency of elastic-wave well treatment methods.

关键词： Elastic wave well treatment oil well rate Zipf’s law rank distribution slope coefficient

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Machine learning for deep elastic strain engineering of semiconductor electronic band structure and effective mass

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npj Computational Materials 2021年第1期7卷 694-703页

作者： evgenii Tsymbalov Zhe Shi Ming Dao Subra Suresh Ju Li Alexander Shapeev Skolkovo Institute of Science and Technology MoscowRussia Department of Materials Science and Engineering and Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyCambridgeMAUSA Nanyang Technological University SingaporeRepublic of Singapore

The controlled introduction of elastic strains is an appealing strategy for modulating the physical properties of semiconductor *** the recent discovery of large elastic deformation in nanoscale specimens as diverse as silicon and diamond,employing this strategy to improve device performance necessitates first-principles computations of the fundamental electronic band structure and target figures-of-merit,through the design of an optimal straining *** simulations,however,call for approaches that combine deep learning algorithms and physics of deformation with band structure calculations to custom-design electronic and optical *** by this challenge,we present here details of a machine learning framework involving convolutional neural networks to represent the topology and curvature of band structures in *** calculations enable us to identify ways in which the physical properties can be altered through“deep”elastic strain engineering up to a large fraction of the ideal *** capable of active learning and informed by the underlying physics were presented here for predicting the bandgap and the band *** training a surrogate model with ab initio computational data,our method can identify the most efficient strain energy pathway to realize physical property *** power of this method is further demonstrated with results from the prediction of strain states that influence the effective electron *** illustrate the applications of the method with specific results for diamonds,although the general deep learning technique presented here is potentially useful for optimizing the physical properties of a wide variety of semiconductor materials。

关键词： strain deformation electronic

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三元Hf-C-N体系的空位有序结构及其力学性质和电子性质的第一性原理研究

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物理学报 2021年第21期70卷 229-239页

作者：彭军辉 Tikhonov evgenii 西北工业大学材料学院材料发现国际中心西安710072 太原工业学院材料工程系太原030008

采用第一性原理方法,研究了三元Hf-C-N体系的空位有序结构及其力学性质和电子性质.首先采用第一性原理和进化算法,预测得到8种可能存在的热力学稳定的Hf-C-N空位有序结构;这些结构都具有岩盐结构,与实验发现的无序固溶体的结构类型一致... 详细信息

采用第一性原理方法,研究了三元Hf-C-N体系的空位有序结构及其力学性质和电子性质.首先采用第一性原理和进化算法,预测得到8种可能存在的热力学稳定的Hf-C-N空位有序结构;这些结构都具有岩盐结构,与实验发现的无序固溶体的结构类型一致.本文的预测结果证明了Hf-C-N空位化合物能够以有序结构形式存在,空位与C,N原子都位于[Hf6]八面体间隙,这一结构特点与Hf C_x的相同.然后采用第一性原理方法,计算了Hf-C-N空位有序结构的力学性质,发现除C∶N=1∶4外,相同C/N下,随着空位浓度的增大,Hf-C-N的体模量、剪切模量、弹性模量、Pugh比、维氏硬度等降低;而Hf6CN4(空位浓度为1/6)的维氏硬度高于Hf_5CN_4(无空位),表现出空位硬化现象.最后,计算了Hf-C-N空位有序结构的态密度和晶体轨道哈密顿分布,发现其具有强共价性和金属性;且随着空位浓度增大,总体键强减弱,因而模量减小.

关键词： Hf-C-N空位有序结构空位维氏硬度第一性原理方法

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空位对Hf-Ta-C体系的结构、力学性质及电子性质影响的第一性原理研究

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无机材料学报 2022年第1期37卷 51-57页

作者：彭军辉 TIKHONOV evgenii 西北工业大学材料学院材料发现国际中心西安710072 太原工业学院材料工程系太原030008

本研究理论预测了三元Hf-Ta-C空位有序结构以及空位对力学性质的影响。采用第一性原理进化晶体结构预测软件USPEX,预测得到了5种热力学稳定和3种亚稳的(Hf,Ta)C_(1-x)空位有序结构,这些结构都属于岩盐结构。采用第一性原理方法,计算了(H... 详细信息

本研究理论预测了三元Hf-Ta-C空位有序结构以及空位对力学性质的影响。采用第一性原理进化晶体结构预测软件USPEX,预测得到了5种热力学稳定和3种亚稳的(Hf,Ta)C_(1-x)空位有序结构,这些结构都属于岩盐结构。采用第一性原理方法,计算了(Hf,Ta)C_(1-x)空位有序结构的力学性质,并分析了力学性质随空位浓度的变化。(Hf,Ta)C_(1-x)都具有较高的体模量、剪切模量、杨氏模量和维氏硬度;各(Hf,Ta)C_(1-x)的Hf/Ta比相同时,其模量、硬度等随空位浓度增大而减小。最后,计算了(Hf,Ta)C_(1-x)的电子态密度,发现其均具有强共价性和弱金属性。本研究结果对于了解Hf-Ta-C体系的空位结构及其力学性质和应用,具有重要参考价值。

关键词： Hf-Ta-C体系空位有序结构维氏硬度第一性原理方法

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Studying the direction of hydraulic fracture in carbonate reservoirs:Using machine learning to determine reservoir pressure

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Petroleum Research 2023年第2期8卷 226-233页

作者： Dmitriy A.Martyushev Inna N.Ponomareva evgenii V.Filippov Department of Oil and Gas Technologies Perm National Research Polytechnic UniversityPerm614990Russia Department of Oil and Gas Fields Development LLC《LUKOIL-PERM》Perm614068Russia

Hydraulic fracturing(HF)is an effective way to intensify oil production,which is currently widely used in various conditions,including complex carbonate *** the conditions of the field under consideration,the hydraulic fracturing leads to a significant differentiation of technological efficiency indicators,which makes it expedient to study the patterns of crack formation in *** were carried out for all wells,which were considered as the objects of impact,to assess the spatial orientation of the cracks *** developed indirect method was used for this purpose,the reliability of which was confirmed by geophysical *** the analysis,it was found that in all cases,the crack is oriented in the direction of the section of the development system element characterized by the maximum reservoir *** the same time,the reservoir pressure values for all wells were determined at one point in time(at the beginning of HF)using machine learning *** reliability of the machine learning methods used is confirmed by the high convergence with the actual(historical)reservoir pressures obtained during hydrodynamic studies of *** obtained conclusion about the influence of the reservoir pressure on the patterns of fracture formation should be taken into account when planning hydraulic fracturing under the conditions studied.

关键词： Hydraulic fracturing direction Machine learning Actual field data Correlation coefficient Well flow rate Well geophysical studies Carbonate reservoir

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Subnanosecond high-voltage breakdown initiated in high-pressure nitrogen by a runaway electron beam

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High Voltage 2017年第2期2卷 56-59页

作者： Alexander G.Burachenko Victor F.Tarasenko evgenii Kh.Baksht Institute of High Current Electronics SB RAS Tomsk 634055Russia National Research Tomsk State University Tomsk 634050Russia National Research Tomsk Polytechnic University Tomsk 634050Russia

This study reports on subnanosecond breakdowns initiated on high pressure nitrogen by a runaway electron beam in an inhomogeneous electric *** is shown that a diffuse discharge with a duration of≥1 ns is formed in the gas *** are reported for the first time on collector measurements of a supershort avalanche electron beam downstream of an anode foil at a nitrogen pressure of 0.5–1.2 *** beam pulsewidth at these pressures is∼90 *** a nitrogen pressure of 1.2 MPa,the number of electrons with an energy>70 keV recorded by the collector is 4×10^(6)/cm^(2).

关键词： field initiated beam

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