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Visible light optical coherence tomography measures retinal oxygen metabolic response to systemic oxygenation

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Light(Science & Applications) 2015年第1期4卷 197-206页

作者： Ji Yi Wenzhong Liu Siyu Chen vadim Backman Nader Sheibani Christine M.Sorenson Amani A.Fawzi Robert A.Linsenmeier Hao F.Zhang Department of Biomedical Engineering Northwestern UniversityEvanstonIL 60208USA McPherson Eye Research Institute University of WisconsinMadisonWI 53705USA Department of Ophthalmology Northwestern UniversityChicago Illinois 60611USA Department of Neurobiology Northwestern UniversityEvanstonIL 60208USA

The lack of capability to quantify oxygen metabolism noninvasively impedes both fundamental investigation and clinical diagnosis of a wide spectrum of diseases including all the major blinding diseases such as age-related macular degeneration,diabetic retinopathy,and *** visible light optical coherence tomography(vis-OCT),we demonstrated accurate and robust measurement of retinal oxygen metabolic rate(rMRO2)noninvasively in rat *** continuously monitored the regulatory response of oxygen consumption to a progressive hypoxic *** found that both oxygen delivery,and rMRO2 increased from the highly regulated retinal circulation(RC)under hypoxia,by 0.2860.08 μL min(^-1)(p,0.001),and 0.2060.04 μL min(^-1)(p,0.001)per 100 mmHg systemic pO2 reduction,*** increased oxygen extraction compensated for the deficient oxygen supply from the poorly regulated choroidal *** from an oxygen diffusion model based on previous oxygen electrode measurements corroborated our in vivo *** believe that vis-OCT has the potential to reveal the fundamental role of oxygen metabolism in various retinal diseases.

关键词： oxygen metabolism retinal circulation visible light optical coherence tomography

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Efficacy and safety of COVID-19 vaccination in patients with cirrhosis

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World Journal of Hepatology 2022年第7期14卷 1470-1479页

作者： Vladimir Ivashkin Albina Ismailova Ksenia Dmitrieva Roman Maslennikov Maria Zharkova Salekh Aliev Vyacheslav Bakhitov vadim Marcinkevich Department of Internal Medicine Gastroenterology and HepatologySechenov UniversityMoscow 119435Russia Department of Internal Diseases Consultative and Diagnostic Center№2 of Department of HealthMoscow 107764Russia Administration Consultative and Diagnostic Center№2 of Department of HealthMoscow 107764Russia The First Hospital Surgery Department Pirogov Russian National Research Medical UniversityMoscow 117997Russia

BACKGROUND The clinical efficacy and safety of vaccination against novel coronavirus disease 2019(COVID-19)in patients with cirrhosis have not been evaluated *** To evaluate the clinical efficacy and safety of vaccination against COVID-19 in patients with *** This was a retrospective cohort study of patients with *** first cohort included patients vaccinated with Gam-COVID-Vac(Sputnik V);the second one consisted of unvaccinated *** The study included 89 vaccinated patients and 148 unvaccinated *** were 4 cases of COVID-19 in the vaccinated group and 24 cases in the unvaccinated group(P=0.035).No severe cases of COVID-19 were revealed in the vaccinated group,while there were 12 ones in the unvaccinated group(P=0.012)with 10 deaths detected(P=0.012).The vaccine efficacy was 69.5%(95%confidence interval[CI]:18.5%-94.4%)against symptomatic cases of COVID-19,100%(95%CI:25.1%-100.0%)against severe cases,and 100%(95%CI:1.6%-100.0%)against death associated with *** efficacy of full vaccination with revaccination against symptomatic cases of COVID-19 was 88.3%(95%CI:48.0%-99.6%).The overall mortality rate was higher in the unvaccinated group than in the vaccinated group(17.1%vs 3.0%;P=0.001).Higher Child-Turcotte-Pugh class cirrhosis(hazard ratio[HR]=4.13,95%CI:1.82-9.35)and higher age(HR=1.08,95%CI:1.04-1.15)were independent predictors of overall mortality,while vaccination had a protective effect(HR=0.09,95%CI:0.01-0.76).There was no significant difference in liver-related mortality(P=0.135)or the incidence of liver decompensation(P=0.077),bleeding esophageal varices(P=0.397),and vascular events(P=0.651)between the two groups of *** Vaccination against COVID-19 in patients with cirrhosis is effective and safe.

关键词： Coronavirus Vaccination Revaccination Booster SARS-CoV-2 Sputnik V

社会支持、自我效能感、人际沟通对留学生的心理调适水平影响作用研究

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社会支持、自我效能感、人际沟通对留学生的心理调适水平影响作用...

作者： Bessonov vadim 上海交通大学

学位级别：硕士

当代商业环境迅速变得越来越国际化。随着越来越多的员工工作国际化,员工如何适应国际化的工作环境和新的文化环境,已成为一个重要的商业问题。事实上,一些外籍人士能够比其他人更快速、轻松地适应新环境,另一些人则步履艰难,这之间为... 详细信息

当代商业环境迅速变得越来越国际化。随着越来越多的员工工作国际化,员工如何适应国际化的工作环境和新的文化环境,已成为一个重要的商业问题。事实上,一些外籍人士能够比其他人更快速、轻松地适应新环境,另一些人则步履艰难,这之间为什么存在差异的问题并没有得到明确解答。随着全球化的扩展和中国经济的快速发展,来华留学的外国学生数量也在不断增加。因此,他们的文化适应问题同样非常重要。本研究力图回答以下研究问题:在新的文化环境下,哪些因素影响留学生的心理调试水平?为回答这一问题,研究探讨了留学生感知到的社会支持、自我效能感与心理调适之间的关系。并提出,留学生感知到的社会支持与其在新的文化情境中的心理调适水平具有正向关系,自我效能感中介了这一关系。同时,本研究提出,在文化适应过程中,留学生与来自母国的人群、当地人群、国际化人群的沟通频度是一个重要的调节因子。为了验证以上假设,本研究设计、开展了两轮调查问卷,在上海四所大学收集了来自41个国家的125名留学生的调查数据。所有参加者均为全日制大学本科、硕士或博士学位的留学生或就读于语言课程的外国学生。参加者学的专业包括了管理,国际业务,建筑,金融,经济,生物医学工程、中文等专业。数据分析结果表明,领悟社会支持、一般自我效能感与心理调适三个主要研究变量之间的关系与上述假设一致。研究结果还表明,与母国人群的沟通频次负向调节了自我效能感和心理调适之间的关系,即,与母国人群较高的沟通频次弱化了自我效能感和心理调适的关系。与国际人群的沟通频次则正向调节了自我效能和心理调适之间的关系,即,与国际人群较高的沟通频次增强了自我效能感和心理调适水平之间的正向关系。关于留学生和本地人群沟通频次的调节作用,在本研究中没有得到支持。论文讨论了数据分析的结果与意义,最后指出了研究的局限性和未来研究的方向。

关键词：文化适应心理调适领悟社会支持一般自我效能感留学生人际沟通

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Hidden Mass Boson

Journal of Modern Physics 2012年第8期3卷 686-693页

作者： Ivanov Mikhail Jakovlevich Mamaev vadim Konstantinovich Central Institute of Aviation Motors Moscow Russia

The evidences of the hidden mass boson existence are presented following the fruitful ideas of M. Planck and A. Einstein and using empirical data of modern physics. Within this article main parameters of this mass particle are predicted and its possible structure is analyzed. Moreover, the close system of nonlinear conservative equations and the spread system of Maxwell linear equations are written in the frame of phenomenological description of the hidden mass continuous medium. The displacement current, the Umov-Pointing vector and the physical vacuum polarization have been described adequately in our paper. We discuss some applications of our methodology for simulations of nature and technical device processes. In particular, numerical solutions for cosmic jets and air breathing engines are shown.

关键词： Vacuum Mathematical Physics Hidden Mass Boson Electromagnetic Equations Conservation Laws Vacuum Polarization Displacement Currents Cosmic Jets Air Breathing Engines

Surface bioactivation of PEEK by neutral atom beam technology

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Bioactive Materials 2019年第1期4卷 132-141页

作者： Joseph Khoury Irina Selezneva Sergei Pestov vadim Tarassov Artem Ermakov Andrey Mikheev Mikhail Lazov Sean R.Kirkpatrick Dmitry Shashkov Alexandre Smolkov Exogenesis Corporation BillericaMAUSA Institute of Theoretical and Experimental Biophysics Russian Academy of SciencesPushchinoMoscow RegionRussia MIREA–Russian Technological University MoscowRussia OAO Technotransservice Engineering MoscowRussia

Polyetheretherketone(PEEK)is an alternative to metallic implants and a material of choice in many applications,including orthopedic,spinal,trauma,and *** titanium(Ti)and Ti-alloys are widely used in many intraosseous implants due to its biocompatibility and ability to osseointegrate,negatives include stiffness which contributes to shear stress,radio-opacity,and *** surgeons prefer to use PEEK due to its biocompatibility,similar elasticity to bone,and radiolucency,however,due to its inert properties,it fails to fully integrate with *** Neutral Atom Beam(ANAB)technology has been successfully employed to demonstrate enhanced bioactivity of PEEK both in vitro and in *** this study,we further characterize surfaces of PEEK modified by ANAB as well as elucidate attachment and genetic effects of dental pulp stem cells(DPSC)exposed to these *** modification resulted in decreased contact angle at 72.9±4.5°as compared to 92.4±8.5°for control(p<0.01)and a decreased average surface roughness,however with a nano-textured surface *** treatment also increased the ability of DPSC attachment and proliferation with considerable genetic differences showing earlier progression towards osteogenic *** surface modification is achieved without adding a coating or changing the chemical composition of the PEEK *** together,we show that ANAB processing of PEEK surface enhances the bioactivity of implantable medical devices without an additive or a coating.

关键词： PEEK neutral activation

Electrical triggering of earthquakes:results of laboratory experiments at spring-block models

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Earthquake Science 2017年第4期30卷 167-172页

作者： Victor A.Novikov Vladimir I.Okunev vadim N.Klyuchkin Jing Liu Yuri Ya.Ruzhin Xuhui Shen Joint Institute for High Temperatures of Russian Academy of Sciences MoscowRussia Institute of Earthquake Science China Earthquake AdministrationBeijingChina Pushkov Institute of Terrestrial Magnetism and Radio Wave Propagation TroitskMoscow RegionRussia Institute of Crustal Dynamics China Earthquake AdministrationBeijingChina

Recently published results of field and laboratory experiments on the seismic/acoustic response to injection of direct current （DC） pulses into the Earth crust or stressed rock samples raised a question on a possibility of electrical earthquake triggering. A physical mechanism of the considered phenomenon is not clear yet in view of the very low current density （10-7-10-s A/m^2） generated by the pulsed power systems at the epicenter depth （5-10 km） of local earthquakes occurred just after the current injection. The paper describes results of laboratory ＂earthquake＂ triggering by DC pulses under conditions of a spring-block model simulated the seismogenic fault. It is experimentally shown that the electric triggering of the laboratory ＂earthquake＂（sharp slip of a movable block of the spring-block system） is possible only within a range of subcritical state of the system, when the shear stress between the movable and fixed blocks obtains 0.98-0.99 of its critical value. The threshold of electric triggering action is about 20 A/m^2 that is 7-8 orders of magnitude higher than estimated electric current density for Bishkek test site （Northern Tien Shan, Kirghizia） where the seismic response to the man-made electric action was observed. In this connection, the electric triggering phenomena may be explained by contraction of electric current in the narrow conductive areas of the faults and the corresponding increase in current density or by involving the secondary triggering mechanisms like electromagnetic stimulation of conductive fluid migration into the fault area resulted in decrease in the fault strength properties.

关键词： Earthquake simulation Spring-block model Electric pulse Triggering threshold

Is the existence of a J/ψJ/ψbound state plausible?

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Science Bulletin 2021年第24期66卷 2462-2470,M0003页

作者： Xiang-Kun Dong vadim Baru Feng-Kun Guo Christoph Hanhart Alexey Nefediev Bing-Song Zou CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Institut für Theoretische Physik Ⅱ Ruhr-Universität BochumBochum D-44780Germany Institute for Theoretical and Experimental Physics NRC“Kurchatov Institute” Moscow 117218Russia Institute for Advanced Simulation Institut für Kernphysik and Jülich Center for Hadron PhysicsForschungszentrum JülichJülich D-52425Germany P.N.Lebedev Physical Institute of the Russian Academy of Sciences Moscow 119991Russia Moscow Institute of Physics and Technology Moscow 141700Russia School of Physics Central South UniversityChangsha 410083China

In a recent measurement LHCb reported pronounced structures in the J/ψJ/ψ*** of the various possible explanations of those is that they emerge from non-perturbative interactions of vector *** is thus important to understand whether it is possible to form a bound state of two charmonia interacting through the exchange of gluons,which hadronise into two pions at the longest *** this paper,we demonstrate that,given our current understanding of hadron-hadron interactions,the exchange of correlated light mesons(pions and kaons)is able to provide sizeable attraction to the di-J/ψsystem,and it is possible for two J/ψmesons to form a bound *** a side result we find from an analysis of the data for theψ/(2 S)J/ψππtransition including bothππand KK final state interactions an improved value for theψ(2 S)→J/ψtransition chromo-electric polarisability:|αψ(2 S)J/ψ|=(1.8±0.1)GeV-3,where the uncertainty also includes the one induced by the final state interactions.

关键词： Fully-charm tetraquark Hadronic molecule Exotic hadron Dispersion relation

Thz Radiation under Tunneling in Asymmetric Double Quatum Wells

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Journal of Electromagnetic Analysis and Applications 2011年第7期3卷 271-276页

作者： Menberu Mengesha Svetlana Koshvaya vadim Mal’nev 不详

The asymmetric parabolic double quantum wells (DQWs) with resonant levels (the ground state energy in one well co-incides with the first excited state energy in another well) is analyzed. The splitting of these levels and the tunneling times are calculated. If the typical life time of the excited state is much smaller than the tunneling time between wells, the charged particle can radiate as a result of the quantum transition from the excited state to the ground state. In the opposite case, the asymmetric DQWs can be treated as a metastable excited nanosystem regardless of that the dipole transition from the excited state to ground state is permitted. The lifetime of this metastable state can be considerably reduced by putting it into a resonant cavity. The possibility of coherent radiation of an ensemble of asymmetric DQWS is discussed.

关键词： Double Quantum Well Energy Splitting Tunneling Quantum Transitions

Cervical dystonia associated with cavernous angioma of the frontal lobe

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Case Reports in Clinical Medicine 2013年第4期2卷 239-241页

作者： Belenky vadim Victorovich Voitsitsky Anatolii Nikolaevich Neurology Clinic of Dr. Voitsitsky St. Petersburg Russia Neurology Clinic of Dr. Voitsitsky St. Petersburg Russia

Structural lesions of CNS, reported to be associated with torticollis, are mostly restricted to cerebellum, brain stem and basal ganglia. In fact, we know only about two documented frontal lobe mass lesions—meningiomas, associated with torticollis. Our observation of frontal lobe cavernous angioma associated with clinical picture of torticollis confirms the role this area could play in the pathophysiology of involuntary movements. We report a case of patient with torticollis associated with cavernous angioma of the right frontal lobe and presuppose causative role of angioma in the development of our patient’s torticollis.

关键词： Cervical Dystonia Cavernous Angioma Meningioma