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Daily high-dose aspirin does not lower APRI in the Aspirin-Myocardial Infarction Study

The Journal of Biomedical Research 2020年第2期34卷 139-142页

作者： Shilpa Tiwari-Heckler ZGordon Jiang Yury popov Kenneth J.Mukamal Division of Gastroenterology and Hepatology Department of MedicineHarvard Medical SchoolBostonMA 02115USA Division of General Medicine Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMA 02115USA

Antiplatelet agents reduce liver fibrosis by inhibiting platelet activation and platelet-derived growth factor production. Previous cross-sectional epidemiological studies suggest that the use of aspirin is related to reduced liver fibrosis. The Aspirin-Myocardial Infarction Study(AMIS) aims to examine this relationship in a multicenter,randomized, double-blind and placebo-controlled trial. The existing clinical trial of aspirin was conducted to study the benefit of one gram aspirin daily among 4 524 individuals who had experienced at least one documented myocardial infarction. The aspartate aminotransferase(AST)-to-Platelet Ratio Index(APRI) was calculated at baseline and annually from the platelet count and AST levels. Participants in the AMIS trial had a mean baseline APRI of 0.34±0.36, and only 1% individuals had APRI scores higher than 1.0, a common cutoff for cirrhosis. The daily use of aspirin was associated with an increase, rather than a reduction of APRI, by 0.007 per year(95% CI0.002-0.015, P=0.12). The use of aspirin did not significantly affect platelet counts. In a sensitivity analysis of individuals with probable significant fibrosis at baseline(APRI≥0.7), the aspirin group had a sustained reduction in APRI over time, although this change was not significant compared to that in the placebo group. In the AMIS trial, the daily use of high-dose aspirin did not significantly affect APRI, a surrogate index of liver fibrosis. This study highlights the need for de novo clinical trials to investigate the potential benefit of antiplatelet agents on liver fibrosis.

关键词： liver fibrosis aspirin APRI antiplatelet AMIS

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Raman spectra of fine-grained materials from first principles

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npj Computational Materials 2020年第1期6卷 616-622页

作者： Maxim N.popov Jürgen Spitaler Vignaswaran K.Veerapandiyan Eric Bousquet Jiri Hlinka Marco Deluca Materials Center Leoben(MCL)Forschung GmbH Roseggerstrasse 12A-8700 LeobenAustria Physique Théorique des Matériaux QMATCESAMUniversite de LiègeB-4000 Sart-TilmanBelgium Institute of Physics Academy of Sciences of the Czech RepublicNa Slovance 218221 PragueCzech Republic

Raman spectroscopy is an advantageous method for studying the local structure of materials,but the interpretation of measured spectra is complicated by the presence of oblique phonons in polycrystals of polar *** group theory considerations and standard ab initio calculations are helpful,they are often valid only for single *** this paper,we introduce a method for computing Raman spectra of polycrystalline materials from first principles.

关键词： materials spectra principles

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Exploring in-situ combustion effects on reservoir properties of heavy oil carbonate reservoir

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Petroleum Science 2024年第5期21卷 3363-3378页

作者： Aliya Mukhametdinova Tagir Karamov Strahinja Markovic Andrey Morkovkin Aleksander Burukhin Evgeny popov Zi-Qi Sun Ren-Bao Zhao Alexey Cheremisin Skolkovo Institute of Science and Technology(Skoltech) Sikorskogo 11Moscow121205Russia State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Laboratory modeling of in-situ combustion is crucial for understanding the potential success of field trials in thermal enhanced oil recovery(EOR) and is a vital precursor to scaling the technology for field applications. The high combustion temperatures, reaching up to 480℃, induce significant petrophysical alterations of the rock, an often overlooked aspect in thermal EOR projects. Quantifying these changes is essential for potentially repurposing thermally treated, depleted reservoirs for CO_(2) *** this study, we depart from conventional combustion experiments that use crushed core, opting instead to analyze the thermal effects on reservoir properties of carbonate rocks using consolidated samples. This technique maintains the intrinsic porosity and permeability, revealing combustion's impact on porosity and mineralogical alterations, with a comparative analysis of these properties pre-and post-combustion. We characterize porosity and pore geometry evolution using low-field nuclear magnetic resonance, X-ray micro-computed tomography, and low-temperature nitrogen adsorption. Mineral composition of the rock and grain-pore scale alterations are analyzed by scanning electron microscopy and X-ray *** analysis shows a significant increase in carbonate rocks' porosity, pore size and mineral alterations, and a transition from mixed-wet to a strongly water-wet state. Total porosity of rock samples increased in average for 15%-20%, and formation of new pores is registered at the scale of 1-30 μm ***-temperature exposure results in the calcite and dolomite decomposition, calcite dissolution and formation of new minerals—anhydrite and fluorite. Increased microporosity and the shift to strongly water-wet rock state improve the prospects for capillary and residual CO_(2) trapping with greater ***, these findings highlight the importance of laboratory in-situ combustion modeling on consolidated rock over tests that use crushed core, an

关键词： In-situ combustion Thermal EOR Carbonates Porosity and pore size MicroCT NMR SEM CO_(2)storage

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Inverse Problems in Solid Mechanics and Ultrasonic

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Journal of Mechanics Engineering and Automation 2017年第6期7卷 307-311页

作者： Aleksandar popov Department of Solid Mechanics Institute of Mechanics-Bulgarian Academy of Science Sofia 1113 Bulgaria

The IP （inverse problem） in solid mechanics have emerged through the 20th century and measured. Nowadays has accept the classification of inverse problems in solid mechanics [1]： retrospective IP, boundary IP, coefficient IP, geometric IP. The IPs in theory of elasticity, theory of plasticity, theory of strengthening, fatigue theory, fracture theory micro-structural of polycrystalline materials are formulated and solved. The method of high frequency theory of ultrasonic waves is used. The results which are obtained here show, that all coefficients and geometrical characteristics of imperfections in the material are functions only of longitudinal and transversal velocities and attenuation of ultrasonic waves, which are measured, according ASTM E 494： 2015. The received relationships from this article could be used for NDE （non-destructive evaluation） of the coefficients and the geometrical characteristics of imperfections in polycrystalline materials.

关键词： IP solid mechanics ultrasonic

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腐殖质生理活性及其与化学组成关系的研究进展

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农业资源与环境学报 2021年第4期38卷 598-610页

作者：宋鸽 popov Alexander Ivanovich 石峰黑龙江大学中俄学院哈尔滨150080 俄罗斯圣彼得堡国立大学地球科学研究所圣彼得堡199034 黑龙江大学生命科学学院哈尔滨150080

腐殖质(HS)是生物体外具备生物学活性的最稳定有机物形式之一。本文综述了HS的化学组成、结构特征和生理活性,依据HS化学组成、结构特征和生理活性的相互关系探讨了HS具有生理活性的内在机制。HS化学组成具有不确定性,超分子结构假设目... 详细信息

腐殖质(HS)是生物体外具备生物学活性的最稳定有机物形式之一。本文综述了HS的化学组成、结构特征和生理活性,依据HS化学组成、结构特征和生理活性的相互关系探讨了HS具有生理活性的内在机制。HS化学组成具有不确定性,超分子结构假设目前被普遍接受。HS通过促进根毛形成和侧根发育、激活质膜H+-ATP酶产生有利的电化学梯度以及自身酸性官能团的螯合作用等促进植物对矿质元素的吸收利用;HS具有类激素活性,植物根际促生细菌(PGPR)分泌物或HS自体组分吲哚-3-乙酸(IAA)能够激活细胞质膜H+-ATPase,HS还能够增加内源植物激素水平,促进植物生长发育;HS通过介导信使NO激活细胞质膜H+-ATPase,清除HS与细胞作用产生的活性氧(ROS),HS通过NO和抗氧化酶调节细胞内ROS稳态,介导根系发育和形态结构。本文还着重探讨了HS生理活性与化学组成的相关性,其中官能团—COOH和—OH活性位点的作用、醌基的电子传递,以及HS亲水疏水平衡与HS生理活性密切相关。未来HS研究工作的重点在于深入研究HS分子结构、明确具备生理活性的“共性结构原件”、阐明HS诱导胞内信号传导通路之间的交叉反馈机制、揭示HS对细胞内物质和能量代谢相关基因表达的调节机制。

关键词：腐殖质 H+-ATPase 类激素活性信使NO 羧基羟基醌基亲水疏水平衡

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V2551 Cyg:a pulsating star with enigmatic peculiarities

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Research in Astronomy and Astrophysics 2017年第7期17卷 57-66页

作者： Diana P.Kjurkchieva Velimir A.popov Dragomir V.Marchev Kenneth T.Menzies Nikola I.Petrov Department of Physics Shumen University IRIDA Observatory Rozhen NAO Tigh Speuran Observatory Institute of Astronomy and NAO Bulgarian Academy of Sciences

Intensive photometric and spectral observations of the variable star V2551 Cyg are *** light curve shape reveals that the target is a pulsating star, contrary to its previous classification as an eclipsing binary. The period and amplitude of the light curve, the amplitudes of color changes and the radial velocity curve of V2551 Cyg are similar to those of a high-amplitude δ Scuti variable. The target seems to pulsate with the fundamental mode. However, V2551 Cyg exhibits several important peculiarities：（i） the decreasing branch of its light curve is steeper than the increasing one;（ii） the radial velocity curve has a flat section in the phase range 0.7-1.2 and short increase of the negative radial velocity at phase 0.7;（iii） the rotational velocity is quite big for a HADS star;（iv） the Fourier coefficients of V2551 Cyg are quite different from those of HADS stars. The target classification is difficult due to these peculiarities.

关键词： stars variables delta Scuti - stars variables RR Lyrae - stars individual (V2551 Cyg)

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Subchronic Oral Cadmium Exposure Exerts both Stimulatory and Suppressive Effects on Pulmonary Inflammation/Immune Reactivity in Rats

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Biomedical and Environmental Sciences 2019年第7期32卷 508-519页

作者： KULAS Jelena NINKOV Marina TUCOVIC Dina popov Aleksandrov Aleksandra UKROPINA Mirela CAKIC MILOSEVIC Maja MUTIC Jelena KATARANOVSKI Milena MIKROV Ivana Immunotoxicology group Department of Ecology Institute for Biological Research 'Sinisa Stankovic ' University of Belgrade 142 Bulevar despota Stefana Belgrade 11000 Serbia Institute of Zoology Faculty of Biology University of Belgrade 16 Studentskitrg Belgrade 11000 Serbia Innovation center of the Faculty of Chemistry University of Belgrade 12-16 Studentskitrg 11000 Belgrade Serbia Institute of Physiology and Biochemistry Faculty of Biology University of Belgrade 16 Studentskitrg Belgrade 11000 Serbia

Objective The aim of this study is to investigate the effects of oral cadmium(Cd) ingestion on the pulmonary immune response. Methods Determination of Cd content in lungs and histopathological evaluation of the tissue was performed in rats following 30-day oral Cd administration(5 and 50 mg/L). Antioxidant enzyme defense(superoxide dismutase and catalase), cell infiltration, and production of tumor necrosis factor(TNF) and interferon(IFN)-γ, as well as the activity of myeloperoxidase(MPO), nitric oxide(NO), and various cytokines [interleukin(IL)-1β, IL-6, IL-10, and IL-17] were investigated. Results Cd caused tissue damage and cell infiltration in the lungs, and this damage was more pronounced at higher doses. Cd deposition resulted in lung inflammation characterized by a dose-dependent IL-1β increase in lung homogenates, increased TNF levels at both doses, and IL-6 stimulation at low doses with inhibition observed at higher doses. Cd exerted differential effects on lung leukocytes isolated by enzyme digestion, and these effects were characterized by a lack of change in the production of reactive oxygen and nitrogen species, an inhibition of IL-1β and TNF, and stimulation of MPO and IFN-γ. The higher capacity of Cd-exposed lung cells to respond to the opportunistic pathogen Staphylococcus epidermidis was demonstrated in vitro. Conclusion The potential of ingested Cd to exert both proinflammatory and immunosuppressive effects on pulmonary tissue inflammation and immune reactivity highlights the complex immunomodulatory actions of this metal.

关键词： Rats Oral cadmium administration Lungs Cytokine response

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Recent Russian remote sensing investigations in Antarctica within the framework of scientific traverses

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Advances in Polar Science 2015年第2期26卷 113-121页

作者： Sergey V.popov Polar Marine Geosurvey Expedition (PMGE) 24 Pobeda Str.St.-PetersburgLomonosov198412Russia

This paper includes a short historical review of Russian and Soviet scientific traverses to study the Antarctic inland. The first traverse left on April 2, 1956. It resulted in the opening of the first Russian inland research station named Pionerskaya and provided the first geophysical and glaciological data on regions inland of the Antarctic coast. By 1965, a number of regional inland scientific traverses had been completed and. the first Atlas of Antarctica was published in 1966. The atlas presented the main achievements of that time. After the discovery of Lake Vostok, Russian scientists commenced remote sensing investigations to study this unique natural phenomenon. The propagation of acoustic and electromagnetic waves in the glacier near Vostok Station were measured to provide important geophysical data. Radio-echo sounding data showed that Lake Vostok is isolated and separated from the rest of the Antarctic subglacial hydrosphere. The total area of the lake is 15 790 km2, excluding 365 km^2 occupied by 11 islands. Reflection seismic soundings of Lake Vostok estimated a total volume of about 6 100 km^3, an average depth of about 400 m, and a maximum depth of 1 200 m. Since 2008, there have been a number of scientific traverses between Mirny and Vostok stations and between Progress and Vostok stations. The data collected during the traverses have provided new insights into sub-ice topography and ice sheet structure, and have led to the discovery of subglacial lakes near Komsomolskaya Station and under Pionerskaya Station.

关键词： Russian scientific traverses Lake Vostok Antarctica remote sensing radio-echo sounding seismic

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Shannon information entropies for position-dependent mass Schrdinger problem with a hyperbolic well

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Chinese Physics B 2015年第10期24卷 45-52页

作者： Sun Guo-Hua Duan popov Oscar Camacho-Nieto Dong Shi-Hai Catedra CONACyT Centro de Investigation en ComputationInstitute Politecnico NacionalUPALM Politehnica University Timisoara Department of Physical Foundations of EngineeringBd.V.Parvan No.2 300223 TimisoaraRomania CIDETEC Instituto Politecnico NacionalUPALM

The Shannon information entropy for the Schrodinger equation with a nonuniform solitonic mass is evaluated for a hyperbolic-type potential. The number of nodes of the wave functions in the transformed space z are broken when recovered to original space x. The position Sx and momentum S p information entropies for six low-lying states are calculated. We notice that the Sx decreases with the increasing mass barrier width a and becomes negative beyond a particular width a,while the Sp first increases with a and then decreases with it. The negative Sx exists for the probability densities that are highly localized. We find that the probability density ρ（x） for n = 1, 3, 5 are greater than 1 at position x = 0. Some interesting features of the information entropy densities ρs（x） and ρs（p） are demonstrated. The Bialynicki-Birula-Mycielski（BBM）inequality is also tested for these states and found to hold.

关键词： position-dependent mass Shannon information entropy hyperbolic potential Fourier transform

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Evaluation of Constants in Fracture Mechanics by Means Non-destructive Testing of Al+3.5%Mg Alloys

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材料科学与工程（中英文B版） 2018年第5期8卷 204-207页

作者： Alexander popov Georgy Dobrev Department of Solid Mechanics Institute of Mechanics-Bulgarian Academy of SciencesSofia 1113Bulgaria Institute of Metal Science Eqipmentand Technologies-BASSofia 1574Bulgaria

The constants in fracture mechanics are fracture toughness(for plane strain),critical value of J—integral,critical value of crack tip opening *** testing under certain conditions to determine them is *** are complicated,long and expensive *** practice,it is interesting to determine the constant in fracture mechanics for elements of constructions by means of non-destructive testing(NDT)(non-destructive evaluations,NDE)from Al+3.5%Mg alloys(according EN 1706).

关键词： Constant in fracture mechanics Al+3.5%Mg alloys ultrasonic hardness

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