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System Design for the Event Horizon Imaging Experiment Using the PECMEO Concept

空间科学学报 2019年第2期39卷 250-266页

作者： KUDRIASHOV volodymyr MARTIN-NEIRA Manuel BARAT Itziar MARTIN IGLESIAS Pertonilo DAGANZO-EUSEBIO Elena ALAGHA Nader VALENTA Vaclav European Space Research and Technology Centre the European Space Agency

The concept for space interferometry from Polar or Equatorial Circular Medium Earth Orbits(the PECMEO concept) is a promising way to acquire the image of the"shadow"of the event horizon of Sagittarius A*with an angular resolution of circa 5 microarcseconds. The concept is intended to decrease the size of the main reflector of the instrument to about 3 m using a precise orbit reconstruction based on Global Navigation Satellite System (GNSS) navigation, inter-satellite range and range-rate measurements, and data from the Attitude and Orbit Determination System (AODS). The paper provides the current progress on the definition of the subsystems required for the concept on the basis of simulations, radio regulations, and available technology. The paper proposes the requirement for the localization of the phase centre of the main reflector. The paper provides information about the visibility of GNSS satellites and the needed accuracies of the AODS. The paper proposes the frequency plan for the instrument and its Inter-Satellite Links (ISLs).The concepts for measurement of range and range-rate using ISLs (as well as for the data exchange at these ISLs) are presented. The block diagram of the interferometer is described and its sensitivity is estimated. The link budget for both ISLs is given as well as their critical components. The calculated measurement quality factors are given. The paper shows the expected performance of the sub-systems of the interferometer. The requirements for the localization of the main reflectors and the information about the availability of the GNSS satellites are based on the simulations results. The frequency plan is obtained according to the PECMEO concept and taking into account the radio regulations. The existing technology defines the accuracies of the AODS, both the link budgets and the fundamental measurement accuracies for ISLs, and the sensitivity of the instrument. The paper provides input information for the development of the orbit r

关键词： Instrumentation Telescope High angular resolution Interferometer Space VLBI

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New insights into the pathogenesis of Peyronie’s disease:A narrative review

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Chronic Diseases and Translational Medicine 2020年第3期6卷 165-181页

作者： Denis V.Krakhotkin volodymyr A.Chernylovskyi Alexandre Mottrie Francesco Greco Ruslan A.Bugaev Outpatient Department Central District HospitalKamenolomniRostov Region.Russia Department of Urology 1 City Clinical Hospital No-4DniproUkraine Department of Urology Onze Li eve Vrouw HospitalAalstBelgium ORSI Academy Me lieBelgium Department of Urology Humanitas GcivazzeniBergamoItaly

Peyronie’s disease(PD)is a benign,progressive fibrotic disorder characterized by scar or plaques within the tunica albuginea(TA)of the *** study provides new insights into the pathogenesis of PD based on data from different studies regarding the roles of cytokines,cell signaling pathways,biochemical mechanisms,genetic factors responsible for fibrogenesis.A growing body of literature has shown that PD is a chronically impaired,localized,wound healing process within the TA and the Smith *** is caused by the influence of different pathological stimuli,most often the effects of mechanical stress during sexual intercourse in genetically sensitive individuals with unusual anatomical TA features,imbalanced matrix metalloproteinase/tissue inhibitor of metalloproteinase(MMP/TIMP),and suppressed antioxidant systems during chronic *** intracellular signal cascades are activated during fibrosis along with low expression levels of their negative regulators and transforming growth factor-β1 *** development of multikinase agents with minimal side effects that can block several signal cell pathways would significantly improve fibrosis in PD tissues by acting on common downstream mediators.

关键词： Peyronie’s disease Cell signal pathway Penile curvature Myofibroblast Extracellular matrix

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Early gestation chorionic villi-derived stromal cells for fetal tissue engineering

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World Journal of Stem Cells 2015年第1期7卷 195-207页

作者： Lee Lankford Taryn Selby James Becker volodymyr Ryzhuk Connor Long Diana Farmer Aijun Wang Department of Surgery University of California Davis Health System Sacramento CA 95817 United States

AIM: To investigate the potential for early gestation placenta-derived mesenchymal stromal cells(PMSCs) for fetal tissue ***: PMSCs were isolated from early gestation chorionic villus tissue by explant culture. Chorionic villus sampling(CVS)-size tissue samples(mean = 35.93 mg)were used to test the feasibility of obtaining large cell numbers from CVS within a clinically relevant timeframe. We characterized PMSCs isolated from 6 donor placentas by flow cytometry immunophenotyping, multipotency assays, and through immunofluorescent staining. Protein secretion from PMSCs was examined using two cytokine array assays capable of probing for over 70 factors in total. Delivery vehicle compatibility of PMSCs was determined using three common scaffold systems: fibrin glue, collagen hydrogel, and biodegradable nanofibrous scaffolds made from a combination of polylactic acid(PLA) and poly(lactic-co-glycolic acid)(PLGA). Viral transduction of PMSCs was performed using a Luciferase-GFPcontaining lentiviral vector and efficiency of transduction was tested by fluorescent microscopy and flow cytometry ***: We determined that an average of 2.09 × 106(SD ± 8.59 × 105) PMSCs could be obtained from CVS-size tissue samples within 30 d(mean = 27 d, SD ± 2.28), indicating that therapeutic numbers of cells can be rapidly expanded from very limited masses of tissue. Immunophenotyping by flow cytometry demonstrated that PMSCs were positive for MSC markers CD105, CD90, CD73, CD44, and CD29, and were negative for hematopoietic and endothelial markers CD45, CD34, and CD31. PMSCs displayed trilineage differentiation capability, and were found to express developmental transcription factors Sox10 and Sox17 as well as neuralrelated structural proteins NFM, Nestin, and S100 β. Cytokine arrays revealed a robust and extensive profile of PMSC-secreted cytokines and growth factors, and detected 34 factors with spot density values exceeding 103. Detected factors had widely div

关键词： Placenta Mesenchymal stromal cells Chorionicvillus Fetal surgery Tissue engineering

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管道不可压缩流动压力脉动(伪声)的数值研究

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振动与冲击 2021年第14期40卷 10-17页

作者：蔡建程谢新俊 MOCHALIN Ievgen BRAZHENKO volodymyr 鄂世举浙江师范大学工学院浙江金华321004 浙江省城市轨道交通智能运维技术与装备重点实验室浙江金华321005

以直管和90°弯管为对象,研究管道不可压缩流动的水动力压力脉动(伪声)特性。分析了不可压缩流动中压力脉动的Poisson方程,并与波动方程进行了比较;在管道进口处设置随时间正弦变化的压力脉动,使用SST k-ω湍流模型,通过数值求解不可压... 详细信息

以直管和90°弯管为对象,研究管道不可压缩流动的水动力压力脉动(伪声)特性。分析了不可压缩流动中压力脉动的Poisson方程,并与波动方程进行了比较;在管道进口处设置随时间正弦变化的压力脉动,使用SST k-ω湍流模型,通过数值求解不可压缩流动的Navier-Stokes方程得到直管和弯管内的脉动流动;比较分析了直管和弯管内的时均流场及脉动流动。结果表明:沿管道流动方向流场压力脉动线性衰减,压力脉动传播整体上呈一维形式,而速度脉动形式紊乱;90°弯头对局部流动影响明显,导致压力和速度脉动均有提高;流场脉动以基频及低次谐波为主,90°弯头导致宽频脉动分量有所提高;归因于压力脉动的椭圆型Poisson方程,扰动的传播速度为无穷大,管道各处压力脉动信号无相位差。

关键词：压力脉动伪声不可压缩流动管道流动数值研究

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Contribution of genotype and ethnicity to bone mineral density variation in Caucasians and Chinese: a test for five candidate genes for bone mass

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Chinese Medical Journal 2005年第15期118卷 1235-1244页

作者： volodymyr Dvornyk LIU Peng-yuan LONG Ji-rong ZHANG Yuan-yuan LEI Shu-feng Robert R Recker DENG Hong-wen Laboratory of Molecular and Statistical Genetics College of Life Sciences Hunan Normal University Changsha 410081 China Osteoporosis Research Center and Department of Biomedical Sciences Creighton University Medical centre Omaha NE 68131 USA

Background Ethnicity is shown to be one of important factors affacting bone mineral density （BMD）. The present study was performed to compare the association of six markers for five candidate genes with BMD variation in two populations of different ethnicity, Caucasian and Chinese, and the contribution of genotype and ethnicity to this variation in the populations. Methods The studied restriction fragment length polymorphisms were BsaH Ⅰ of the calcium-sensing receptor gene, Sac Ⅰ of the α2HS-glycoprotein （AHSG） gene, Pvu Ⅱ and Xba Ⅰ of the oestrogen receptor α gene, Apa Ⅰ of the vitamin D receptor （VDR） gene and BstB Ⅰ of the parathyroid hormone gene. The association of these markers with BMD was analysed by one-way and two-way ANOVA with adjustment for covariates. Results Two polymorphisms, AHSG-Sac Ⅰ and VDR-Apa Ⅰ , showed no association with BMD, while the others were associated with BMD variation at some skeletal sites in either males or females. The polymorphisms indicated clear distinctions between the associations depending on ethnicity, gender and skeletal site. Similar patterns were observed in their contribution to the total population BMD variation. Ethnicity appears to have a larger effect on the total population BMD variation in females than in males. It may account, on the average, for about 2% total population BMD variation at the spine of females and about 1% at the hip of males and females. Conclusion The results of the present study suggest that significant interethnic differentiation at some loci may contribute to the significant interethnic difference in BMD. However, this contribution apparently is not large.

关键词： bone mineral density genotype ethnicity association osteoporosis

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The bactericidal spectrum and virucidal effects of silver nanoparticles against the pathogens in sericulture

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Open Journal of Animal Sciences 2013年第3期3卷 169-173页

作者： Wenchu Li Kapalunenko volodymyr Yeyuan Wang Dimchev volodymyr Department of Sericulture Science College of Animal Science South China Agricultural University Guangzhou China Ukrainian State Scientific Research Institute of Nanobiotechnologies and Resource Reservation Kylv Ukraine

Silver nanoparticles have mainly been studied for their antimicrobial potential against bacteria, but have also proven to be active against several types of viruses, even against pebrine as well. Methods: Petri dishes and transmission electronic microscope were applied to observe silver nanoparticles against bacteria strains and nuclear polyhedral viruses (NPV) and cytoplasmic polyhedral viruses (CPV). For biological test, 108 CFU/mL NPV with strong pathogenicity, and the NPV samples treated with 1:100 ratio of “Sumerian Silver” for 8 hrs were sprayed on the mulberry leaves, respectively, for silkworm rearing. Conclusion: Silver nanoparticle solution showed a strong bactericidal effect against both G+ and G﹣bacterial pathogenic strains from Bombyx mori and mulberry. Under transmission electronic microscope (TEM), Bacillus sp. Samples showed light particles in the cells when treated with silver nanoparticles, in contrast, untreated samples showed homogeneity contents. Further, NPV particles showed no significant differences between treated and untreated samples, but CPV showed strong effects that almost all CPV were collapsed. For biological test, “Sumerian Silver” treated NPV showed no diseased silkworm but nearly all silkworms were dead with no treatment. It seems like that silver nanoparticles were proved to be more effective against CPV than that of NPV. The significant differences between two antivirus or virucidal mechanism should be greatly aroused the scientific interest.

关键词： Silver Nanoparticles Bactericidal and Virucidal Agent Sericulture Pathogens

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强吸气旋转圆筒壁面湍流边界层建模及计算

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力学学报 2020年第5期52卷 1323-1333,I0003页

作者： Ievgen Mochalin 林静雯蔡建程 volodymyr Brazhenko 鄂世举浙江师范大学工学院浙江金华321004 浙江省城市轨道交通智能运维技术与装备重点实验室浙江金华321005

提出了湍流边界层的一种简单、快速计算方法,用以求解强吸气作用下旋转圆筒表面边界层流动.首先,理论分析了同心圆筒间的旋转流体运动,外筒静止、内筒旋转且为多孔吸气条件.强吸气情况下旋转流动主要表现为内筒壁面附近的边界层流动,基... 详细信息

提出了湍流边界层的一种简单、快速计算方法,用以求解强吸气作用下旋转圆筒表面边界层流动.首先,理论分析了同心圆筒间的旋转流体运动,外筒静止、内筒旋转且为多孔吸气条件.强吸气情况下旋转流动主要表现为内筒壁面附近的边界层流动,基于这一事实得到了周向速度分布的解析表达式.其次,通过引入新参数扩展Cebeci-Smith代数湍流模型,使其能考虑流线曲率、壁面吸气、低Reynolds数效应等因素.针对这些因素的综合影响,采用解析修正和经验参数对模型进行调整.同时,基于Reynolds应力湍流模型的仿真结果,校准代数湍流模型中的经验参数.最后,给出基于广义Cebeci-Smith湍流模型的旋转壁面边界层流动的迭代算法,该算法适用于需要特殊迭代过程的轴向及周向流动均匀情况.计算了不同旋转速度和吸气强度组合工况下的边界层流动,其周向速度和湍流强度分布与基于Reynolds应力湍流模型的计算结果非常接近.并且表明,当Reynolds应力湍流模型数值模拟预测内筒边界层为稳定层流时,该方法也再现了相同初始条件下的层流边界层.

关键词：湍流边界层旋转同心圆筒壁面吸气 Cebeci-Smith代数湍流模型

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Beam dynamics studies on the 100 MeV/100 kW electron linear accelerator for NSC KIPT neutron source

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Chinese Physics C 2012年第7期36卷 653-660页

作者：裴士伦池云龙王书鸿裴国玺周祖圣侯汨 Mykola Ayzatskiy Ivan Karnaukhov volodymyr Kushnir Viktor Mytrochenko Andrey Zelinsky Institute of High Energy Physics Chinese Academy of Sciences Kharkov Institute of Physics and Technology National Science Center

We designed a 100 MeV/100 kW electron linear accelerator for NSC KIPT, which will be used to drive a neutron source on the basis of subcritical assembly. Beam dynamics studies have been conducted to reach the design requirements （E=100 MeV, P=100 kW, dE/E 〈1% for 99% particles）. In this paper, we will present the progress of the design and the dynamic simulation results. For high intensity and long beam pulse linear accelerators, the BBU effect is one big issue; special care has been taken in the accelerating structure design. To satisfy the energy spread requirement at the linac exit, the particles with large energy difference from the synchronous particle should be eliminated at a low energy stage to ease the design of the collimation system and radiation shielding. A dispersion free chicane with 4 bending magnets is introduced downstream of the 1st accelerating section; the unwanted particles will be collimated there.

关键词： beam dynamics linear accelerator BBU collimation system neutron source

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Modeling of Sectional and Multi-stage Thermoelectric Modules as Waste Heat Recuperators

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Journal of Electrical Engineering 2014年第3期2卷 124-131页

作者： Tetiana Manyk volodymyr Bilynskyj-Slotylo Department of Computer Science Bukovyna State University of Finance and Economics Chernivtsi 58000 Ukraine Department of Physics of Semiconductors and Nanostructures Chernivtsi National University Chernivtsi 58012 Ukraine Department of Thermogenerators Institute of Thermoeleetricity Chernivtsi 58029 Ukraine

The results of computer simulation of segmented and cascaded thermoelectric generator modules are presented. That use of Bi 2 Te 3 -based materials as cold sections and PbTe-based materials as hot sections for two-section modules in the temperature range 303-773 K, allows to multiply their efficiency by 1.28 as compared to single-section ones. Cascade structures are characterized by better efficiency and lesser output power compared with the sectional, although construction investigated modules are designed to the equal areas.

关键词：电气控制控制理论电气测量集中参数

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Numerical Simulations of Nonlinear Interaction of Space Charge Waves in Microwave and Millimeter Wave Range in n-InN Films Using Negative Differential Conductivity

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Modeling and Numerical Simulation of Material Science 2014年第3期4卷 136-142页

作者： Abel Garcia-Barrientos volodymyr Grimalsky CIICAp Autonomous University of Morelos State (UAEM) Morelos México Electronics and Computer Science Department Research Center on Information Technology and Systems Autonomous University of Hidalgo State (UAEH) Hidalgo México

Numerical simulations of nonlinear interaction of space charge waves in microwave and millimeter wave range in n-InN films have been carried out. A micro- and millimeter-waves frequency conversion using the negative differential conductivity phenomenon is carried out when the harmonics of the input signal are generated. An increment in the amplification is observed in n-InN films at essentially at high-frequencies f < 450 GHz, when compared with n-GaAs films f < 44 GHz. This work provides a way to achieve a frequency conversion and amplification of micro- and millimeter-waves.

关键词： Space Charge Waves InN Film Negative Differential Conductivity

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