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1煤型稀有金属矿床:成因类型、赋存状态和利用评价显示文摘煤和含煤岩系中稀有金属元素的研究,是当今煤地质学研究的热点问题之一。煤和含煤岩系中高度富集并可以开发利用的稀有金属元素包括锂、钪、钛、钒、镓、锗、硒、锆、铌、铪、钽、铀、稀土元素(包括镧系元素和钇)、贵金属元素等。以煤-锗、煤-镓、煤-铀、煤-铌、煤-稀土元素等煤型稀有金属矿床为例,论述了这些矿床的地质成因、赋存状态和利用评价方法。煤型稀有金属矿床的研究,不仅对研究煤层的地质成因、煤层对比、含煤盆地形成与后期改造、区域地质历史演化和突发地质事件可以提供重要的煤地球化学和煤矿物学证据,而且对煤炭经济循环发展、煤炭利用过程中环境保护,以及对国家稀有金属资源安全也具有重要的现实和社会意义。代世峰 任徳贻 周义平 Vladimir VSeredin 李大华 张名泉 James C Hower Colin R Ward 王西勃 赵蕾 宋晓林 2014煤炭学报2014,39,8:111
2美国国立神经疾病和卒中研究所-加拿大卒中网血管性认知障碍统一标准显示文摘背景和目的:1/3的个体会罹患卒中和(或)痴呆,而且,除卒中或痴呆外,2倍于此数的人会出现认知障碍。常用的卒中量表并不能评价认知功能,而痴呆的诊断标准则集中在认知障碍的晚期阶段,且在很大程度上偏向Alzheimer病(AD)的诊断。尚缺乏普遍公认的标准用于识别和描述存在认知障碍的个体,尤其是在早期阶段,而且特别是与血管因素有关的认知障碍或血管性认知障碍。方法:美国国立神经疾病和卒中研究所(MINDS)与加拿大卒中网(CSN)召集临床诊断、流行病学、神经心理学、脑影像学、神经病理学、试验模型、生物标记物、遗传学和临床试验方面的研究人员,为血管性认知障碍的描述和研究推荐一些最低限度的常用的临床和研究标准。结果:将这些讨论的结果发表于此。结论:一个统一标准的制定代表着使用、确认和改进过程中的第一步。使用相同的标准将有助于在认知障碍的早期阶段识别患者,使不同的研究具有可比性,并且通过整合知识来加速研究进展的步伐。Vladimir Hachinski Costantino Iadecola Ron C.Petersen Monique M.Breteler David L.Nyenhuis Sandra E.Black William J.Powers Charles DeCarli Jose G.Merino Raj N.Kalaria Harry V.Vinters David M.Holtzman Gary A.Rosenberg Martin Dichgans John R.Marler Gabrielle G.Leblanc 李焰生(译) 俞羚(译) 高枚春(译) 张静芳(译) 熊昕丽(译) 邹静(译) 林岩(译) 潘元美(译) 2007国际脑血管病杂志2007,15,1:63
3山羊豆种质资源形态多样性分析显示文摘采用15个形态性状对43份山羊豆种质资源进行遗传多样性分析,结果表明,山羊豆种质资源遗传变异丰富,多样性指数为1.863,其中俄罗斯南部地区可能是山羊豆形态多样性的分布中心。基于形态性状的聚类分析把43份材料聚为5类,其中第1类15份资源的株高和主茎分枝数明显高于其他类,且叶量丰富,营养性状表现良好;结实性状中荚果长和百粒重较大,综合性状表现较好,可以从中筛选合适的材料作为引种驯化和育种的试验材料。王俊娥 王赞 王运琦 高洪文 Vladimir Chapurin 2008植物遗传资源学报2008,9,2:29
4单晶炉导流筒、热屏及炭毡对单晶硅生长影响的优化模拟显示文摘在CZ法生长太阳能级单晶硅中,单晶炉的导流筒、热屏和炭毡对晶体生长有很大影响。通过对上述三个部件进行改进优化,并通过数值模拟对优化前后晶体和熔体的热场、热屏外表面与石英坩埚内壁面之间的氩气流场以及晶体中的热应力进行分析,得出以下结论:石墨导流筒的引入减少了炉体上部的氩气流动涡胞,进而减少了S iO在单晶炉上部的沉积;优化后的热屏减少了加热器对晶体的烘烤,使结晶速率加快;优化后的侧壁炭毡阻止了加热器向上部的热损失。优化后在加热器功耗不变时,结晶速率至少可提高35%,而不增加宏观位错的发生概率。苏文佳 左然 Vladimir Kalaev 2010人工晶体学报2010,39,2:22
5花青素抗氧化损伤及细胞凋亡的作用研究显示文摘目的:探索花青素对H2O2引起的Huh7细胞氧化应激、细胞凋亡的作用及其机制。方法:对H2O2和花青素干预培养的Huh7细胞,应用MTT法检测细胞活力,荧光探针DCFH-DA测定细胞内活性氧(ROS)生成量,免疫印迹测定Akt、磷酸化激活的c-Jun蛋白水平。结果:H2O20.8mmol/L孵育1小时可显著诱导Huh7细胞损伤,细胞活力下降到(49.27±3.2)%,ROS生成量是未处理细胞的3.56倍。细胞经花青素50μmol/L与H2O2共孵育后,细胞存活率提高到(81.2±2.34)%;花青素能显著抑制H2O2引起的Huh7细胞ROS生成,ROS生成下降74%(P<0.01)。花青素抑制H2O2引起Huh7细胞死亡和ROS生成的效应随剂量增加而加强。花青素抑制H2O2激发Huh7细胞磷酸化c-Jun表达,提高细胞Akt水平。结论:花青素抑制H2O2引起的Huh7细胞氧化应激损伤所导致的细胞死亡,其作用机制在于减少细胞内活性氧生成,抑制H2O2激活磷酸化c-Jun,提高细胞Akt水平。余晶 鲍中英 徐玉敏 Vladimir Khaoustov Boris Yoffe 2009中西医结合肝病杂志2009,19,1:21
6水稻土施硅对土壤-水稻系统中镉的降低效果显示文摘水稻中镉的积累造成人类健康的风险,增加水稻硅素能减轻镉中毒症状,降低稻米镉积累,但是硅对重金属的作用机理尚不清楚。主要研究了在中度和高度镉污染的土壤中,通过施用固态和液态的富硅物质对土壤-水稻系统中镉的吸收和转运的影响,探明决定镉和硅在根与芽的质外体和共质体中的作用机理。试验结果表明:(1)在中度和高度污染的土壤中,镉在土壤-作物系统中的转移和积累情况是不同的,可以通过富硅物质中的单硅酸与镉离子的相互作用,增加镉在硅物质表面的吸附来减少镉在土壤中的流动;(2)富硅物质可以降低水稻根和芽中镉的积累,在高度镉污染的情况下,施用硅可以使镉大量积累在水稻根及其共质体中,并降低根及其共质体中镉的转换和积累;(3)新鲜土壤中水萃取态的单硅酸含量与镉在土壤-作物系统中的流动性、转运以及积累等主要参数密切相关。魏晓 张鹏博 赵丹丹 Elena Bocharnikova Vladimir Matichenkov Demin Dmitry 2018生态学报2018,38,5:21
7基于改进YOLOv3算法的公路车道线检测方法显示文摘针对YOLOv3算法在检测公路车道线时存在准确率低和漏检概率高的问题,提出一种改进YOLOv3网络结构的公路车道线检测方法.该方法首先将图像划分为多个网格,利用K-means++聚类算法,根据公路车道线宽高固有特点,确定目标先验框数量和对应宽高值;其次根据聚类结果优化网络Anchor参数,使训练网络在车道线检测方面具有一定的针对性;最后将经过Darknet-53网络提取的特征进行拼接,改进YOLOv3算法卷积层结构,使用GPU进行多尺度训练得到最优的权重模型,从而对图像中的车道线目标进行检测,并选取置信度最高的边界框进行标记.使用Caltech Lanes数据库中的图像信息进行对比试验,实验结果表明,改进的YOLOv3算法在公路车道线检测中平均准确率(Mean average precision, mAP)为95%,检测速度可达50帧/s,较YOLOv3原始算法mAP值提升了11%,且明显高于其他车道线检测方法.崔文靓 王玉静 康守强 谢金宝 王庆岩 MIKULOVICH Vladimir Ivanovich 2022自动化学报2022,48,6:20
8Ultra-thin, planar, Babinet-inverted plasmonic metalenses显示文摘We experimentally demonstrate the focusing of visible light with ultra-thin,planar metasurfaces made of concentrically perforated,30-nm-thick gold films.The perforated nano-voids—Babinet-inverted(complementary)nano-antennas—create discrete phase shifts and form a desired wavefront of cross-polarized,scattered light.The signal-to-noise ratio in our complementary nano-antenna design is at least one order of magnitude higher than in previous metallic nano-antenna designs.We first study our proof-of-concept‘metalens’with extremely strong focusing ability:focusing at a distance of only 2.5 mm is achieved experimentally with a 4-mm-diameter lens for light at a wavelength of 676 nm.We then extend our work with one of these‘metalenses’and achieve a wavelength-controllable focal length.Optical characterization of the lens confirms that switching the incident wavelength from 676 to 476 nm changes the focal length from 7 to 10 mm,which opens up new opportunities for tuning and spatially separating light at different wavelengths within small,micrometer-scale areas.All the proposed designs can be embedded on-chip or at the end of an optical fiber.The designs also all work for two orthogonal,linear polarizations of incident light.Xingjie Ni Satoshi Ishii Alexander V Kildishev Vladimir M Shalaev 2013Light(Science & Applications)2013,2,1:20
9皮质下小血管病诊断的共识声明显示文摘血管性认知损害是用于描述一组涉及大血管和小血管的散发性和遗传性异质性疾病的诊断术语。皮质下小血管病可导致腔隙性梗死和进行性白质损害。被称为宾斯旺格病(Binswanger's disease, BD)的进行性白质损害患者构成了从单纯血管性疾病到合并神经变性病变的疾病谱。BD患者是一个相对同质性的亚组,存在缺氧缺血、腔隙性梗死和炎症,它们协同作用破坏血脑屏障和髓鞘。通过临床、脑脊液、神经心理学和影像学检查获得的多模式疾病标记物能促进该亚组患者的鉴别。本共识声明确定了一系列基于基础病理学改变的潜在生物学标记物,这将有助于诊断以及将来协作性治疗试验的患者选择。Gary A Rosenberg Anders Wallin Joanna M Wardlaw Hugh S Markus Joan Montaner Leslie Wolfson Costantino Iadecola Berislav V Zlokovic Anne Joutel Martin Dichgans Marco Duering Reinhold Schmidt Amos D Korczyn Lea T Grinberg Helena C Chui Vladimir Hachinski 王训师 张劼 陈涵丰 俞娅美 徐子奇 罗本燕 2016国际脑血管病杂志2016,24,6:18
10陕西秦岭平河梁自然保护区小型兽类的组成与分布显示文摘2005年9月利用铗日法辅以陷阱法对位于秦岭山脉南坡东段的平河梁自然保护区及牛背梁自然保护区小型兽类进行了调查,共设置采集点10个;2460铗日中共捕获小型兽类689只,隶属于3目6科19属27种(另有两种鼢鼠和一种鼯鼠系其他手段捕获),平均捕获率28.01%。对捕获的27种小型兽类生态和垂直分布进行分析结果表明:平河梁保护区3个群落的Shannon-Weiner多样性指数在2.9288-3.3639之间,Pielou均匀性指数在0.7669-0.8602之间。在上述调查的基础上,结合前人对邻近地区的调查,据一些物种的分布特点,订出平河梁自然保护区小型兽类的名录,计48种,结果显示秦岭南坡东段小型兽类的物种多样性和丰富度要高于秦岭其他地区。另在考察中采集到白尾鼹(Parascaptor leucura)、小纹背鼩鼱(Sorex bedfordiae)、斯氏鼢鼠(Myospalaxsmithii)、川西白腹鼠(Niviventer excelsior),在秦岭山区尚属首次记录。还整理了秦岭南坡小型兽类名录,认为秦岭南坡有小型兽类55种,在动物地理区划上应属于西南区。秦岭 孟祥明 Alexei Kryukov Vladimir Korablev Marina Pavlenko 杨兴中 王应祥 蒋学龙 2007Zoological Research2007,28,3:17
11ICD-11精神与行为障碍(草案)关于物质使用障碍与成瘾行为障碍诊断标准的进展显示文摘精神活性物质使用在全球范围内已经成为严重的公共卫生问题和社会问题。据联合国毒品与犯罪办公室估计,全球非法药物滥用者达3.5%-7.0%,对个人健康和社会发展带来严重危害。与其他精神疾病相比,精神活性物质所致精神障碍具有症状表现丰富、病情复杂多变、共病情况明显等特点,因此在疾病的诊治方面均存在一定的难度。目前国际上精神疾病的诊断体系主要有美国精神障碍诊断与统计手册(Diagnostic and Statistical Manual of Mental Disorders,DSM)和国际疾病分类(International Classification of Diseases,ICD)两大体系,在临床上也已得到广泛应用。但是随着临床工作经验的积累以及医学研究的迅速发展,原有体系中的部分内容已经不再适用。杜江 钟娜 Vladimir Poznyak 郝伟 赵敏 2018中华精神科杂志2018,51,2:15
12Metal-containing nanomaterials as lubricant additives: State-of-the-art and future development显示文摘This review focuses on the effect of metal-containing nanomaterials on tribological performance in oil lubrication. The basic data on nanolubricants based on nanoparticles of metals, metal oxides, metal sulfides, nanocomposities, and rare-earth compounds are generalized. The influence of nanoparticle size, morphology, surface functionalization, and concentration on friction and wear is analyzed. The lubrication mechanisms of nanolubricants are discussed. The problems and prospects for the development of metal-containing nanomaterials as lubricant additives are considered. The bibliography includes articles published during the last five years.Igor E.UFLYAND Vladimir A.ZHINZHILO Victoria E.BURLAKOVA 2019Friction2019,7,2:15
13Circulating tumor cells in pancreatic cancer patients:Enrichment and cultivation显示文摘AIM:To investigate the feasibility of separation and cultivation of circulating tumor cells(CTCs)in pancreatic cancer(Pa C)using a filtration device.METHODS:In total,24 Pa C patients who were candidates for surgical treatment were enrolled into the study.Peripheral blood samples were collected before an indicated surgery.For each patient,approximately8 m L of venous blood was drawn from the antecubitalveins.A new size-based separation Meta Cell?technology was used for enrichment and cultivation of CTCs in vitro.(Separated CTCs were cultured on a membrane in FBS enriched RPMI media and observed by inverted microscope.The cultured cells were analyzed by means of histochemistry and immunohistochemistry using the specific antibodies to identify the cell origin.RESULTS:CTCs were detected in 16 patients(66.7%)of the 24 evaluable patients.The CTC positivity did not reflect the disease stage,tumor size,or lymph node involvement.The same percentage of CTC positivity was observed in the metastatic and non-metastatic patients(66.7%vs 66.7%).We report a successful isolation of CTCs in Pa C patients capturing proliferating cells.The cells were captured by a capillary action driven size-based filtration approach that enabled cells cultures from the viable CTCs to be unaffected by any antibodies or lysing solutions.The captured cancer cells displayed plasticity which enabled some cells to invade the separating membrane.Further,the cancer cells in the'bottom fraction',may represent a more invasive CTC-fraction.The CTCs were cultured in vitro for further downstream applications.CONCLUSION:The presented size-based filtration method enables culture of CTCs in vitro for possible downstream applications.Vladimir Bobek Robert Gurlich Petra Eliasova Katarina Kolostova 2014World Journal of Gastroenterology2014,20,45:15
14Russian Nuclear Rocket Engine Design for Mars Exploration显示文摘This paper is to promote investigation into the nuclear rocket engine (NRE) propulsion option that is considered as a key technology for manned Mars exploration. Russian NRE developed since the 1950s in the former Soviet Union to a full-cale prototype by the 1990s is viewed as advantageous and the most suit-able starting point concept for manned Mars mission application study. The main features of Russian het-erogeneous core NRE design are described and the most valuable experimental performance results are summarized. These results have demonstrated the significant specific impulse performance advantage of the NRE over conventional liquid rocket engine (LRE) propulsion technologies. Based on past experience, the recent developments in the field of high-temperature nuclear fuels, and the latest conceptual studies, the developed NRE concept is suggested to be upgraded to the nuclear power and propulsion system (NPPS), more suitable for future manned Mars missions. Although the NRE still needs development for space appli-cation, the problems are solvable with additional effort and funding.Vadim Zakirov Vladimir Pavshook 2007Tsinghua Science and Technology2007,12,3:14
15Capecitabine and cisplatin with or without cetuximab for patients with previously untreated advanced gastric cancer (EXPAND): a randomised, open-label phase 3 trial显示文摘Florian Lordick Yoon-Koo Kang Hyun-Cheol Chung Pamela Salman Sang Cheul Oh Gy?rgy Bodoky Galina Kurteva Constantin Volovat Vladimir M Moiseyenko Vera Gorbunova Joon Oh Park Akira Sawaki Ilhan Celik Heiko G?tte Helena Melezínková Markus Moehler 2013Lancet Oncology2013,,6:14
16电力系统主动解列的可行解列时窗研究显示文摘解列时刻是决定解列是否成功的关键因素。常规解列研究基于解列前的静态潮流信息,对动态过程中的稳定性问题利用强假设进行规避,忽略解列时刻的研究。本文首次对主动解列的解列时刻问题展开系统性分析,利用暂态能量函数量化解列动态过程中孤岛的稳定性,利用孤岛失稳的临界能量确定暂态稳定意义下的可行解列时窗,以保证解列后孤岛的暂态稳定性。研究表明,因扰动背景不同,孤岛的可行解列时窗呈现出:任何时刻均可解列、小于某个临界时刻、大于某个临界时刻、呈现断续的时窗特征以及可行解列时窗为空等五种不同的情况。本文首次从机理上解释和刻画主动解列的解列时刻特征,为进一步研究主动解列问题提供了新的思路和支撑。丁磊 郭一忱 陈青 Vladimir Terzija 2015电工技术学报2015,30,12:14
17Distribution and changes of active layer thickness(ALT) and soil temperature(TTOP) in the source area of the Yellow River using the GIPL model显示文摘Active layer thickness(ALT) is critical to the understanding of the surface energy balance, hydrological cycles, plant growth, and cold region engineering projects in permafrost regions. The temperature at the bottom of the active layer, a boundary layer between the equilibrium thermal state(in permafrost below) and transient thermal state(in the atmosphere and surface canopies above), is an important parameter to reflect the existence and thermal stability of permafrost. In this study, the Geophysical Institute Permafrost Model(GIPL) was used to model the spatial distribution of and changes in ALT and soil temperature in the Source Area of the Yellow River(SAYR), where continuous, discontinuous, and sporadic permafrost coexists with seasonally frozen ground. Monthly air temperatures downscaled from the CRU TS3.0 datasets, monthly snow depth derived from the passive microwave remote-sensing data SMMR and SSM/I, and vegetation patterns and soil properties at scale of 1:1000000 were used as input data after modified with GIS techniques. The model validation was carried out carefully with in-situ ALT in the SAYR interpolated from the field-measured soil temperature data. The results of the model indicate that the average ALT in the SAYR has significantly increased from 1.8 m in 1980 to 2.4 m in 2006 at an average rate of 2.2 cm yr–1. The mean annual temperature at the bottom of the active layer, or temperature at the top of permafrost(TTOP) rose substantially from –1.1℃ in 1980 to –0.6℃ in 2006 at an average rate of 0.018℃ yr–1. The increasing rate of the ALT and TTOP has accelerated since 2000. Regional warming and degradation of permafrost has also occurred, and the changes in the areal extent of regions with a sub-zero TTOP shrank from 2.4×104 to 2.2×104 km2 at an average rate of 74 km2 yr–1. Changes of ALT and temperature have adversely affected the environmental stability in the SAYR.LUO DongLiang JIN HuiJun Sergei MARCHENKO Vladimir ROMANOVSKY 2014Science China Earth Sciences2014,57,8:14
18Cell-free circulating tumor DNA in cancer显示文摘Cancer is a common cause of death worldwide.Despite significant advances in cancer treatments,the morbidity and mortality are still enormous.Tumor heterogeneity,especially intratumoral heterogeneity,is a significant reason underlying difficulties in tumor treatment and failure of a number of current therapeutic modalities,even of molecularly targeted therapies.The development of a virtually noninvasive 'liquid biopsy' from the blood has been attempted to characterize tumor heterogeneity.This review focuses on cell-free circulating tumor DNA(ctDNA) in the bloodstream as a versatile biomarker.ctDNA analysis is an evolving field with many new methods being developed and optimized to be able to successfully extract and analyze ctDNA,which has vast clinical applications.ctDNA has the potential to accurately genotype the tumor and identify personalized genetic and epigenetic alterations of the entire tumor.In addition,ctDNA has the potential to accurately monitor tumor burden and treatment response,while also being able to monitor minimal residual disease,reducing the need for harmful adjuvant chemotherapy and allowing more rapid detection of relapse.There are still many challenges that need to be overcome prior to this biomarker getting wide adoption in the clinical world,including optimization,standardization,and large multicenter trials.Zhen Qin Vladimir A.Ljubimov Cuiqi Zhou Yunguang Tong Jimin Liang 2016Chinese Journal of Cancer2016,35,5:14
19电力系统频率动态行为衍变与分析方法需求综述显示文摘低惯量可再生能源发展导致电力系统运行形态发生变化,频率动态行为愈加复杂,频率安全稳定面临新的挑战。阐述频率动态响应过程,综述频率动态行为量化特征和分析方法,强调基于人工智能分析方法的优势和前景。从可再生能源发电强波动、电源非同步并网低惯量及大功率缺额与连锁故障高风险三个角度,分析电力系统运行形态变化,探讨对频率分析与控制的新要求。剖析可再生能源快速发展背景下电力系统等效惯量的内涵,综述可再生能源虚拟惯量控制方法,强调多类型虚拟惯量协调控制的优势和前景。总结频率分析与控制领域中亟待研究的重点内容,给出后续研究建议。张恒旭 曹永吉 张怡 李常刚 阮佳程 VLADIMIR Terzija 2021山东大学学报(工学版)2021,51,5:14
20Support-Vector Networks显示文摘Corinna Cortes Vladimir Vapnik 1995Machine Learning1995,,3:13
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