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Impact of Climate and Grazing on Biomass Components of Eastern Russia Typical Steppe

Journal of Integrative Agriculture 2014年第6期13卷 1183-1192页

作者： ubugunov leonid Rupyshev Yuriy ubugunov Vasiliy HOU Xiang-yang Vishnyakova Oxana Lavrentieva Irina ubugunova Vera REN Wei-bo DING Yong Institute of General and Experimental Biology Siberian Branch of Russian Academy of Sciences Grassland Research Institute Chinese Academy of Agricultural Sciences

Spatial and structural characteristics of plant communities in the steppe ecosystems of the Baikal region, Russian Federation have been researched in connection with climate change and grazing. The present study, based on a total of 15 typical steppe sampling plots, investigated above-ground biomass （AGB）, below-ground biomass （BGB）, total biomass （TB） and root：shoot ratios （R：S） and their relationships with climatic factors and grazing. All biomass components varied widely depending on the climatic parameters and the degree of grazing affected transformation. A strong negative correlation between mean annual temperature （MAT） and total plant biomass was revealed for all study area. Mean annual precipitation （MAP） signiifcantly affected communities productivity increasing only in the south of the region. Due to the large and mountainous territory, the inlfuence of latitude and elevation （mountain） factors on the components of the biomass were studied. Although all studied plant steppe communities were transformed by uncontrolled grazing, their productivity is signiifcantly reduced only at plots with maximum digression. Vegetation shift is an indicator of climate change, as well as providing a diagnostic tool to build predictive models. Based on the complex index of effective precipitation, it was revealed that at the end of last century in the steppes of the Baikal region the structural and production processes will be affected by an arid climate trend.

关键词： steppe productivity climate grazing transformation Baikal region

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A new method for precise optical measurements of the sub-micron height of levitation of droplet clusters

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Particuology 2024年第4期87卷 173-178页

作者： Alexander A.Fedorets Eduard E.Kolmakov leonid A.Dombrovsky University of Tyumen 6 Volodarskogo StTyumen625003Russia Engineering Faculty Ariel UniversityP0.B.3407000ArielIsrael Joint Institute for High Temperatures 17A Krasnokazarmennaya StMoscow111116Russia

Droplet clusters levitating over the locally heated water surface are considered a very promising phe-nomenon of microfluidics for the potential use of the droplets as unique microreactors for microbio-logical experiments.A new optical method is suggested for precise measurements of the sub-micron levitation height of single droplets.The method is based on the analysis of variable colors of the inter-ference halo around the droplet.For the first time,it is possible to measure the extremely low downward velocity of droplets,which grow due to steam condensation.This velocity was found to be 5-8 nm/s.The height of the levitation of various droplets just before their coalescence with a layer of water was also determined.Such measurements might be used for the verification of sophisticated models for the droplet levitation to be developed for a very thin layer of humid air under the droplet when the Knudsen effect should be taken into account.

关键词： Precise measurements Interferometric method Droplet cluster Levitation height

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Centroid Hom-associative Algebras and Centroid Hom-Lie Algebras

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Acta Mathematica Sinica,English Series 2024年第4期40卷 935-961页

作者： Yu Xiu BAI leonid A.BOKUT Yu Qun CHEN Ze Rui ZHANG Department of Mathematics Teaching Guangzhou Civil Aviation CollegeGuangzhou 510403P.R.China Sobolev Institute of Mathematics Novosibirsk 630090Russia Novosibirsk State University Novosibirsk 630090Russia School of Mathematical Sciences South China Normal UniversityGuangzhou 510631P.R.China

In this article,we construct free centroid hom-associative algebras and free centroid hom-Lie algebras.We also construct some other relatively free centroid hom-associative algebras by applying the Gr?bner-Shirshov basis theory for(unital)centroid hom-associative algebras.Finally,we prove that the"Poincaré-Birkhoff-Witt theorem"holds for certain type of centroid hom-Lie algebras over a field of characteristic 0,namely,every centroid hom-Lie algebra such that the eigenvectors of the mapβlinearly generates the whole algebra can be embedded into its universal enveloping centroid hom-associative algebra,and the linear basis of the universal enveloping algebra does not depend on the multiplication table of the centroid hom-Lie algebra under consideration.

关键词： Centroid hom-Lie algebra centroid hom-associative algebra Gr?bner-Shirshov basis

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A systematic review of cytoreductive prostatectomy outcomes and complications in oligometastatic disease

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Asian Journal of Urology 2024年第2期11卷 208-220页

作者： Andrey Morozov leonid Chuvalov Mark Taratkin Mikhail Enikeev leonid Rapoport Nirmish Singla Eric Barret Elena Poddubskaya Maria Borodina Georg Salomon Juan Gomez Rivas Dmitry Enikeev Institute for Urology and Reproductive Health Sechenov UniversityMoscowRussia Young Academic Urologists EAUthe Netherlands Department of Urology James Buchanan Brady Urological InstituteThe Johns Hopkins University School of MedicineBaltimoreUSA Department of Urology Institut Mutualiste MontsourisParisFrance Sechenov University MoscowRussia Hertsen Moscow Oncology Research InstituteMoscowRussia Hertsen Moscow Oncology Research Institute MoscowRussia Martini Clinic University Medical Center Hamburg-EppendorfHamburgGermany Department of Urology Clinico San Carlos University HospitalMadridSpain Department of Urology Medical University of ViennaViennaAustria

Objective: To analyze outcomes and complications of cytoreductive prostatectomy (CRP) for oligometastatic prostate cancer (PCa) in order to elucidate its role in this space.Methods: We performed a systematic literature search using three databases (Medline, Scopus, and Web of Science). The primary endpoints were oncologic outcomes. The secondary endpoints were complication rates and functional results.Results: In all studies, overall survival was better or at least comparable variable in the groups with CRP compared to no local treatment. The greatest benefit from CRP in 5-year overall survival in one study was 67.4% for CRP versus 22.5% for no local treatment. Cancer-specific survival (CSS) showed the same trend. Several authors found significant benefits from CSS in the CRP group: from 79% vs. 46% to 100% vs. 61%. CRP was a predictor of better CSS (hazard ratio 0.264, p=0.004). Positive surgical margin rates differed widely from 28.6% to 100.0%. Urinary continence in CRP versus RP for localized PCa was significantly lower (57.4% vs. 90.8%, p<0.0001). Severe incontinence occurred seldom (2.5%-18.6%). Total complication rates after CRP differed widely, from 7.0% to 43.6%. Rates of grades 1 and 2 events prevailed. Patients on ADT alone also showed a considerable number of complications varying from 5.9% to 57.7%.Conclusion: CRP improves medium-term cancer control in patients with oligometastatic PCa. The morbidity and complication rates of this surgery are comparable with other approaches, but postoperative incontinence rate is higher compared with RP for localized disease.

关键词： Systematicreview Prostatecancer Oligometastatic Bone metastases Cytoreductive prostatectomy

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Pulsed THz radiation under ultrafast optical discharge of vacuum photodiode

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Frontiers of Optoelectronics 2024年第2期17卷 99-112页

作者： Aleksandr Ushakov Kseniia Mamaeva leonid Seleznev Georgy Rizaev Vladimir Bukin Timophey Dolmatov Pavel Chizhov Vladimir Bagdasarov Sergey Garnov Prokhorov General Physics Institute of the Russian Academy of Sciences Moscow 119991Russia Physical Institute Russian Academy of SciencesMoscow 119991Russia Moscow Institute of Physics and Technology Dolgoprudny 141700Russia Russian Institute for Scientific and Technical Information Moscow 125190Russia

In this paper,we first present an experimental demonstration of terahertz radiation pulse generation with energy up to 5 pJ under the electron emission during ultrafast optical discharge of a vacuum photodiode.We use a femtosecond optical excitation of metallic copper photocathode for the generation of ultrashort electron bunch and up to 45 kV/cm external electric field for the photo-emitted electron acceleration.Measurements of terahertz pulses energy as a function of emitted charge density,incidence angle of optical radiation and applied electric field have been provided.Spectral and polarization characteristics of generated terahertz pulses have also been studied.The proposed semi-analytical model and simulations in COMSOL Multiphysics prove the experimental data and allow for the optimization of experimental conditions aimed at flexible control of radiation parameters.

关键词： Electron emission Vacuum photodiode Ultrafast excitation Terahertz

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气候变化背景下草原生态系统研究热点探讨

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中国草地学报 2013年第5期35卷 124-132页

作者：丁勇侯向阳吴新宏 leonid ubugunov 任卫波萨茹拉孙小龙刘朋涛中国农业科学院草原研究所/中国农业科学院欧亚温带草原研究中心内蒙古呼和浩特010010 俄罗斯科学院西伯利亚分院普通与实验生物学研究所布里亚特共和国乌兰乌德670047 内蒙古自治区生态与农业气象中心内蒙古呼和浩特010051

回顾了近年来关于气候变化与人类活动对草原生态系统的影响与系统响应及适应的研究前沿,并从自然系统维度指出,应该重视气候变化下草原生态系统,尤其是水分胁迫对生态系统的影响及植物生产层适应机制的研究,这将有助于破解草原退化的本... 详细信息

回顾了近年来关于气候变化与人类活动对草原生态系统的影响与系统响应及适应的研究前沿,并从自然系统维度指出,应该重视气候变化下草原生态系统,尤其是水分胁迫对生态系统的影响及植物生产层适应机制的研究,这将有助于破解草原退化的本质与趋势,以挖掘其适应气候变化的潜能;从人类干扰与管理的维度指出,研究人类活动与气候变化两大主要因素共同作用对生态系统的影响,是最符合现实状态的研究,在一个较短的时期内,人类无法阻止和控制气候变化,放牧利用作为主要人类活动是一高度人为可控的管理手段,通过建立放牧制度、放牧强度和放牧时间的多维调控网络,将承担起草原应对气候变化、促进退化草原恢复的重要责任。最后,将以上主要观点进行归纳,提出气候变化背景下草原生态系统研究的5个热点方向及需要突破的相关问题。

关键词：气候变化人类活动草原生态系统响应和适应研究热点

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气候变化对家庭牧场复合系统的影响及其牧民适应

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草业学报 2013年第1期22卷 148-156页

作者：李西良侯向阳 leonid ubugunov 丁勇丁文强尹燕亭运向军张勇中国农业科学院草原研究所内蒙古呼和浩特010010 俄罗斯科学院西伯利亚分院生物公共实验研究所兰州大学草地农业科技学院甘肃兰州730020

家庭牧场土-草-畜-人复合生态系统是北方草原应对气候变化的基本单元,研究其适应性是促进牧区可持续发展的科学基础之一。以草业系统论构建家庭牧场气候变化适应性的研究方法,基于问卷调查研究了内蒙古草原10个旗县599个家庭牧场对气候... 详细信息

家庭牧场土-草-畜-人复合生态系统是北方草原应对气候变化的基本单元,研究其适应性是促进牧区可持续发展的科学基础之一。以草业系统论构建家庭牧场气候变化适应性的研究方法,基于问卷调查研究了内蒙古草原10个旗县599个家庭牧场对气候变化的响应过程。结果表明,1)放牧地、打草场、饲料地、购草作为家庭牧场草料供给途径存在明显的区域分异,饲料地、购草之间具有替代效应;2)以干旱为主的极端气候是气候变化影响家庭牧场的关键因子,雪灾、沙尘暴、大风的影响在内蒙古各地呈现分异格局;3)牲畜、草场是气候变化作用于家庭牧场经营的主要介质,而通过土壤、人群、设施等要素对家庭牧场影响相对较小;4)购草、卖畜是牧户应对极端气候的主要适应行为,分别为保畜与减畜策略,比较而言,保畜策略更为常见。研究认为,家庭牧场复合系统对气候变化的响应发生于草畜-经营界面,草、畜2因子是反馈过程的关键节点。

关键词：家庭牧场气候变化牧民适应响应策略

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温带草原区气候变化及其对植被影响的研究进展

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中国农学通报 2012年第17期28卷 310-316页

作者：丁勇侯向阳 leonid ubugunov 吴新宏尹燕亭李西良运向军中国农业科学院草原研究所呼和浩特010010 俄罗斯科学院西伯利亚分院生物公共实验研究所乌兰乌德670047 兰州大学草地农业科技学院兰州730020

为了深入研究温带草原区气候变化及其对自然-社会-经济系统的影响、系统响应及适应,回顾了温带草原区气候主要要素(如温度、降雨)与旱灾的变化及未来区域气候趋势预测等方面的研究进展,重点总结了气候变化对温带草原植被影响的最新研究... 详细信息

为了深入研究温带草原区气候变化及其对自然-社会-经济系统的影响、系统响应及适应,回顾了温带草原区气候主要要素(如温度、降雨)与旱灾的变化及未来区域气候趋势预测等方面的研究进展,重点总结了气候变化对温带草原植被影响的最新研究成果。研究发现:温带草原区呈现总体气温明显升高,降水区域差异显著,干旱年份增多、旱灾增加的变化趋势。受此影响,植物物候、生理特征、生产力、覆盖度等发生明显的变化。最后指出,在气候变化核心要素预测、研究的时空尺度等方面还不完善,今后应重视开展大尺度气候变化的时空格局,微地形下气候变化的时空异质性等方面研究,同时加强气候变化对草原植被的影响与生态系统响应以及气候变化适应等方面的研究。

关键词：气候变化草原植被温带草原

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Spherically Symmetric Problem of General Relativity for a Fluid Sphere

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Journal of Modern Physics 2024年第4期15卷 401-415页

作者： Valery V. Vasiliev leonid V. Fedorov Institute of Applied Mechanics of Russian Academy of Sciences Moscow Russia

The paper is devoted to a spherically symmetric problem of General Relativity (GR) for a fluid sphere. The problem is solved within the framework of a special geometry of the Riemannian space induced by gravitation. According to this geometry, the four-dimensional Riemannian space is assumed to be Euclidean with respect to the space coordinates and Riemannian with respect to the time coordinate. Such interpretation of the Riemannian space allows us to obtain complete set of GR equations for the external empty space and the internal spaces for incompressible and compressible perfect fluids. The obtained analytical solution for an incompressible fluid is compared with the Schwarzchild solution. For a sphere consisting of compressible fluid or gas, a numerical solution is presented and discussed.

关键词： General Relativity Spherically Symmetric Problem Fluid Sphere

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酿酒酵母中基于CRISPR/Cas9工具的基因编辑与代谢调控研究进展

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微生物学杂志 2024年第2期44卷 1-18页

作者：安迎锋梁瑶崑高嵩 leonid N Valentovich 沈阳农业大学生物科学技术学院辽宁沈阳110161 National Academy of Sciences of Belarus Institute of MicrobiologyBelarus Minsk 220084

CRISPR/Cas9系统已广泛用于各种生物体的基因编辑和代谢工程。本文综述了CRISPR/Cas9在酿酒酵母中的基本原理和实际应用。首先总结了CRISPR/Cas9技术的发展历史、酿酒酵母基因组中基因缺失和多DNA片段插入的成功案例。这一先进的系统减... 详细信息

CRISPR/Cas9系统已广泛用于各种生物体的基因编辑和代谢工程。本文综述了CRISPR/Cas9在酿酒酵母中的基本原理和实际应用。首先总结了CRISPR/Cas9技术的发展历史、酿酒酵母基因组中基因缺失和多DNA片段插入的成功案例。这一先进的系统减少了劳动力,增强了对分子遗传学的理解,加速了微生物工程的发展。其次总结了基于CRISPR/Cas9的系统在生产高附加值化学品和提高酿酒酵母耐应激性方面的研究进展。该综述对酿酒酵母的遗传和合成生物学研究具有重要的参考价值。

关键词：次生代谢产物代谢工程合成生物学抗逆性酿酒酵母

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