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Journal of Geriatric Cardiology 2017年第9期14卷 541-546页

作者： Evgeny N Mikhaylov Tamas Szili-Torok dmitry S Lebedev Arrhythmia Department Almazov National Medical Research Centre Saint-Petersburg Russia Neuromodulation Laboratory Almazov National Medical Research Centre Saint-Petersburg Russia Electrophysiology Unit Cardiology Department Erasmus Medical Center Rotterdam the Netherlands

Heart rhythm disturbances become of special importancewhen patients reach a senior age. Atrial fibrillation （AF） isthe most prevalent arrhythmia among the old age groups,and its impact on morbidity and mortality becomes of para-mount significance. In this population, AF is responsible forsignificant amount of thromboembolic cerebrovascularevents, especially for disabling and fatal strokes, Follow-ing announcement of the special issue of the Journal of Geri-atric Cardiology devoted to heart rhythm disorders in theelderly, a number of submissions have been received withAF as the major topic of authors＇ researches.

关键词： Atrial fibrillation Ablation Efficacy Left atrial appendage Occlusion Safety The elderly

Biofuels and food security

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Frontiers of Agricultural Science and Engineering 2015年第1期2卷 1-12页

作者： dmitry S.STREBKOV All-Russian Research Institute for Electri fi cation of Agriculture (VIESH) 1-st. Veshnyakovsky proezd 2 Moscow 109456 Russia

The major source of energy comes from fossil *** current situation in the fi eld of fuel and energy is becoming more problematic as world population continues to grow because of the limitation of fossil fuels reserve and its pressure on *** review aims to fi nd economic,reliable,renewable and non-polluting energy sources to reduce high energy tariffs in Russian *** is fuel derived directly from plants,or indirectly from agricultural,commercial,domestic,and/or industrial *** alternative energy sources including solar energy and electric power generation are also *** 100 Mt of biomass available for energy purposes is produced every year in *** of the downsides of biomass energy is its potential threatens to food security and forage *** innovative approach proved that multicomponent fuel(80%diesel oil content for motor and 64%for in stove fuel)can remarkably reduce the *** paper proposed that the most promising energy model for future is based on direct solar energy conversion and transcontinental terawatt power transmission with the use of resonant wave-guide technology.

关键词： fossil fuels biofuels food security electric power solar energy

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GaN功率放大器非线性对无线通信系统的影响研究

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GaN功率放大器非线性对无线通信系统的影响研究

Innovation:A state-of-the-art review and typology

2024年全国微波毫米波会议（中国微波年会）

作者：杜宏宇宋章磊万发雨 Vladimir Mordachev Eugene Sinkevich dmitry Viktorovich Kholodnyak 南京信息工程大学圣彼得堡电工大学

本文研究了3.5GHz Ga N功率放大器的非线性特性及其对无线通信系统性能的影响。首先设计了一款S波段Ga N功率放大器,通过实验测试和分析,得到了3.5GHz Ga N功率放大器线性增益45.5d B,饱和功率40.5d Bm,饱和效率26.9%,1d B压缩点34.6d ... 详细信息

本文研究了3.5GHz Ga N功率放大器的非线性特性及其对无线通信系统性能的影响。首先设计了一款S波段Ga N功率放大器,通过实验测试和分析,得到了3.5GHz Ga N功率放大器线性增益45.5d B,饱和功率40.5d Bm,饱和效率26.9%,1d B压缩点34.6d Bm,该输出功率下三阶交调抑制大于24.5d Bc等射频特性。接着在通信系统性能测试中,对功率放大器非线性在QPSK调制方式下对系统误差向量幅度(EVM)和信噪比(SNR)的影响进行了分析。结果表明,在高功率输入条件下,非线性失真显著降低了通信系统的性能。

关键词： GaN功率放大器非线性特性无线通信系统

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International Journal of Innovation Studies 2023年第4期7卷 281-290页

作者： dmitry M.Kochetkov Centre for Science and Technology Studies Leiden UniversityLeidenthe Netherlands Peoples'Friendship University of Russia(RUDN University) MoscowRussia

Innovation is often an object of study in economics and ***,the social and behavioral aspects of innovation acceptance are as important as the economics of product development.A significant portion of the literature considers innovation as a change in the way social actions are conducted,entailing a wide range of social,economic,behavioral,and institutional *** approaches have given rise to the need for a ***(1998)divided innovation into three groups depending on the aspects of the phenomenon:theory of entrepreneurship,technological and social aspects,and strategic *** Sundbo's conceptual framework,this study supplemented and developed it based on recent literature that appeared after ***,this study added new directions at the second level of decomposition and the relationships between different aspects of *** particular,this study analyzed phenomena such as open innovation,agile innovation,and“helix”***,this study developed a novel typology of innovation that expands the theoretical knowledge in this *** on these findings,this study proposed promising areas for future innovation studies.

关键词： Innovation Entrepreneurship Typology Triple helix

A Semi-Implicit Fractional Step Method Immersed Boundary Method for the Numerical Simulation of Natural Convection Non-Boussinesq Flows

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Communications in Computational Physics 2022年第8期32卷 737-778页

作者： dmitry Zviaga Ido Silverman Alexander Gelfgat Yuri Feldman Department of Mechanical Engineering Ben-Gurion University of the NegevP.O.Box 653Beer-Sheva 84105Israel Soreq Nuclear Research Center 81000 YavneIsrael School of Mechanical Engineering Tel Aviv UniversityTel Aviv 6997801Israel

The paper presents a novel pressure-corrected formulation of the immersed boundary method(IBM)for the simulation of fully compressible non-Boussinesq natural convection *** formulation incorporated into the pressure-based fractional step approach facilitates simulation of the flows in the presence of an immersed body characterized by a complex ***,we first present extensive grid independence and verification studies addressing incompressible pressure-driven flow in an extended channel and non-Boussinesq natural convection flow in a differentially heated ***,the steady-state non-Boussinesq natural convection flow developing in the presence of hot cylinders of various diameters placed within a cold square cavity is thoroughly *** obtained results are presented and analyzed in terms of the spatial distribution of path lines and temperature fields and of heat flux values typical of the hot cylinder and the cold cavity *** characteristics of multiple steady-state solutions discovered for several configurations are presented and discussed in detail.

关键词： Natural convection non-Boussinesq flows pressure-corrected immersed boundary method multiple steady state solutions

Medical images classification for skin cancer using quantitative image features with optical coherence tomography

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Journal of Innovative Optical Health Sciences 2016年第2期9卷 8-16页

作者： Wei Gao Valery P.Zakharov Oleg O.Myakinin Ivan A.Bratchenko dmitry N.Artemyev dmitry V.Kornilin Department of Laser and Biotechnical Systems Samara State Aerospace University

Optical coherence tomography(OCT)is employed in the diagnosis of skin ***,quantitative image features extracted from OCT images might be used as indicators to classify the skin *** the present paper,we investigated intensity-based,texture-based and fractalbased features for automatically classifying the melanomas,basal cell carcinomas and pigment *** estimating equations were used to test for differences between the skin tumors.A modified p value of<0.001 was considered statistically *** increase of mean and median of intensity and significant decrease of mean and median of absolute gradient were observed in basal cell carcinomas and pigment nevi as compared with *** decrease of contrast,entropy and fractal dimension was also observed in basal cell carcinomas and pigment nevi as compared with *** results suggest that the selected quantitative image features of OCT images could provide useful information to differentiate basal cell carcinomas and pigment nevi from the *** research is warranted to determine how this approach may be used to improve the classification of skin tumors.

关键词： Optical coherence tomography skin tumor texture analysis fractal analysis differentiate box counting

Discrimination of ventricular tachycardia and localization of its exit site using surface electrocardiography

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Journal of Geriatric Cardiology 2019年第4期16卷 362-377页

作者： Heber Ivan Condori Leandro dmitry S Lebedev Evgeny N Mikhaylov Lang G.F. department of Internal Medicine Pavlov First Saint Petersburg State Medical UniversitySaint-PetersburgRussia Almazov National Medical Research Centre Saint-PetersburgRussia Department of Medical and Biotechnology Systems First Electrotechnical UniversitySaint-PetersburgRussia

Differential diagnosis of supraventricular tachycardia (SVT) and ventricular tachycardia (VT) is of paramount importance for appropriate patient management. Several diagnostic algorithms for discrimination of VT and SVT based on surface electrocardiogram (ECG) analysis have been proposed. Following established diagnosis of VT,a specific origination tachycardia site can be supposed according to QRS complex characteristics. This review aims to cover comprehensive and comparative description of the main VT diagnostic algorithms and to present ECG characteristics which permit to suggest the most common VT origination sites.

关键词： Arrhythmias Electrocardiogram Supraventricular Tachycardia Ventricular

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Human bone graft cytocompatibility with mesenchymal stromal cells is comparable after thermal sterilization and washing followed byγ-irradiation:an in vitro study

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Regenerative Biomaterials 2018年第2期5卷 85-92页

作者： dmitry Labutin Konstantin Vorobyov Svetlana Bozhkova Ekaterina Polyakova Tatyana Vodopyanova Division of Wound Infection Treatment and Prevention Vreden Russian Research Institute of Traumatology and OrthopedicsSt.PetersburgRussian Federation

Human bone allografts present a better alternative to autografts in terms of minimization of the harvesting procedure *** to the use in clinical applications,they require sterilization which aims to reduce *** often comes at the expense of their biological properties as carriers of *** this study,we evaluated the cytocompatibility of human bone allografts processed and sterilized by three different methods withmesenchymal stromal *** morphology,biological and biochemical properties of the extracted bone-conditionedmedium and viability of cells were *** found that chemical sterilization had a strong negative effect on cell viability,whereas thermal sterilization and washing with subsequentγ-irradiation both resulted in a bone graft compatible with the progenitor ***,washing of the bone prior to sterilization allowed solid removal of cell debris and other bone marrow *** together,our findings demonstrate the importance of a proper choice of the bone graft processing method for the production of the biomaterial suitable for tissue engineering.

关键词： bone grafts bone sterilization mesenchymal stromal cells biocompatibility testing

Notes on the family Brassicaceae in China

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Journal of Systematics and Evolution 2009年第3期47卷 202-219页

作者： dmitry A GERMAN Altai State University

A critical revision of the collections of Brassicaceae in some Chinese (PE, XJA, XJBI, XJFA, XJNM, XJU) and foreign (LE, P) herbaria is made. One genus, Neurotropis (DC.) F. K. Mey., and 11 species, Alyssum szarabiacum Nyár., Barbarea stricta Andrz., Erysimum czernjajevii N. Busch, Erysimum kotuchovii D. German, Erysimum mongolicum D. German, Lepidium karelinianum Al-Shehbaz, Matthiola superba Conti, Neurotropis platycarpa (Fisch. & Mey.) F. K. Mey., Ptilotrichum dahuricum Peschkova, Sisymbrium subspinescens Bunge, and Smelowskia micrantha (Botsch. & Vved.) Al-Shehbaz & S. I. Warwick, are reported from China for the first time. Six species, Aphragmus involucratus (Bunge) O. E. Schulz, Dontostemon perennis C. A. Mey., Goldbachia torulosa DC., Lepidium amplexicaule Willd., Neotorularia brevipes (Kar. & Kir.) Hedge & J. Léonard, and Parrya stenocarpa Kar. & Kir., are confirmed to occurr in China. Five species, Dontostemon integrifolius (L.) C. A. Mey., Draba zangbeiensis L. L. Lou, Lepidium alashanicum H. L. Yang, Sinapis arvensis L., and Strigosella brevipes (Bunge) Botsch., are reported as novelties for some provinces in China, and Strigosella hispida (Litv.) Botsch. occurs in Xinjiang, China. However, the occurrence of one genus, Pseudoarabidopsis Al-Shehbaz, O’Kane & Price, and four species, Draba huetii Boiss., Eutrema halophilum (C. A. Mey.) Al-Shehbaz & S. I. Warwick, Galitzkya spathulata (Steph. ex Willd.) V. Bocz., and Pseudoarabidopsis toxophylla (Bieb.) Al-Shehbaz, O’Kane & Price, could not be confirmed in China. The occurrence of six species, Aphragmus bouffordii Al-Shehbaz, Barbarea orthoceras Ledeb., Lepidium latifolium L., Ptilotrichum canescens (DC.) C. A. Mey., Strigosella hispida (Litv.) Botsch., and Strigosella scorpioides (Bunge) Botsch., is not confirmed in certain provinces of China. All names follow the latest taxonomic treatment for relevant groups; detailed morphological descriptions of the newly recorded taxa are provided; and distinguishing c

关键词： Brassicaceae China Cruciferae distribution new record.

西西伯利亚盆地北极油气区侏罗系-白垩系储集层气-水系统平衡模拟

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石油勘探与开发 2022年第2期49卷 319-329页

作者： NOVIKOV dmitry Anatolievich 俄罗斯科学院西伯利亚分校Trofimuk石油地质和地球物理研究所新西伯利亚630900俄罗斯俄罗斯新西伯利亚国立大学新西伯利亚630900俄罗斯

为揭示盐水含量较高的含油气盆地中油气和地下水之间的相平衡,采用新的气-水平衡模拟软件对西西伯利亚盆地北极含油气区进行模拟。研究发现,该区域地层水的含气饱和度(Sg)变化较大,饱和系数(Cs)为0.2~1.0,其数值随深度及地层水总含气饱... 详细信息

为揭示盐水含量较高的含油气盆地中油气和地下水之间的相平衡,采用新的气-水平衡模拟软件对西西伯利亚盆地北极含油气区进行模拟。研究发现,该区域地层水的含气饱和度(Sg)变化较大,饱和系数(Cs)为0.2~1.0,其数值随深度及地层水总含气饱和度的增加而增大。地层水Sg大于1.8 L/L的情况下,气体饱和系数(Cs)均达到临界值1.0,为油气成藏创造了有利条件;而欠饱和水可溶解现有油气藏中的天然气。地层水气体饱和系数与储集层流体类型有关,凝析油气田的气体饱和系数主要为0.8~1.0,而在常规油藏中却相对较低。复杂的气水交换模式表明研究区侏罗系—白垩系储集层中天然气来源具有多样性。

关键词：气-水系统油气聚集侏罗系—白垩系油藏西西伯利亚北极油气区

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