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Estradiol promotes sudden cardiac death in transgenic long QT type 2 rabbits while progesterone is protective

HEART RHYTHM 2012年第5期9卷 823-832页

作者： Odening, Katja E. Choi, Bum-Rak liu, Gong Xin Hartmann, Kathryn Ziv, Ohad Chaves, Leonard Schofield, Lorraine Centracchio, Jason Zehender, Manfred Peng, xuwen Brunner, Michael Koren, Gideon Brown Univ Rhode Isl Hosp Div Cardiol Cardiovasc Res CtrAlpert Med Sch Providence RI 02903 USA Univ Hosp Freiburg Dept Cardiol Freiburg Germany Penn State Univ Coll Med Dept Comparat Med Hershey PA USA

BACKGROUND Postpubertal women with inherited long QT syndrome type 2 (LQT2) are at increased risk for polymorphic ventricular tachycardia (pVT) and sudden cardiac death (SCD), particularly during the postpartum period. OBJECTIVE To investigate whether sex hormones directly modulate the arrhythmogenic risk in LQTS. METHODS Prepubertal ovariectomized transgenic LQT2 rabbits were treated with estradiol (EST), progesterone (PROG), dihydrotestosterone (DHT), or placebo (OVX). RESULTS During 8 weeks of treatment, major cardiac events-spontaneous pVT or SCD-occurred in 5 of the 7 EST rabbits and in 2 of the 9 OVX rabbits (P < .05);in contrast, no events occurred in 9 PROG rabbits and 6 DHT rabbits (P < .01 vs PROG;P < .05 vs DHT). Moreover, EST increased the incidence of pVT (P < .05 vs OVX), while PROG reduced premature ventricular contractions, bigeminy, couplets, triplets, and pVT (P < .01 vs OVX;P < .001 vs EST). In vivo electrocardiographic monitoring, in vivo electrophysiological studies, and ex vivo optical mapping studies revealed that EST promoted SCD by steepening the QT/RR slope (P < .05), by prolonging cardiac refractoriness (P < .05), and by altering the spatial pattern of action potential duration dispersion. Isoproterenol-induced Ca2+ oscillations resulted in early afterdepolarizations in EST-treated hearts (4 of 4), while PROG prevented SCD by eliminating this early afterdepolarization formation in 4 of the 7 hearts (P = .058 vs EST;P < .05 vs OVX). Analyses of ion currents demonstrated that EST increased the density of I-Ca,I-L as compared with OVX (P < .05) while PROG decreased it (P < .05). CONCLUSION This study reveals the proarrhythmic effect of EST and the antiarrhythmic effect of PROG in LQT2 in vivo, outlining a new potential antiarrhythmic therapy for LQTS. KEYWORDS Long QT syndrome;Sex hormones;Arrhythmogenesis;Sudden cardiac death;Transgenic LQT2 rabbit model;Cardiac ion currents;Early afterdepolarization;In vivo electrophysiological study

关键词： Long QT syndrome Sex hormones Arrhythmogenesis Sudden cardiac death Transgenic LQT2 rabbit model Cardiac ion currents Early afterdepolarization In vivo electrophysiological study

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脑脊液IFN-γ IL-4在结核性脑膜炎病程中的动态变化

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中国实用神经疾病杂志 2013年第20期16卷 7-9页

作者：宋孚霞孙旭文王晓彤佴玉刘竹丽刘宏赵裕君山东烟台毓璜顶医院神经内科烟台264000

目的应用间接酶联免疫吸附试验(enzyme-linked immunol sorbance assay,ELISA)检测脑脊液中炎症因子IFN-γ、IL-4的动态变化,探讨其在诊断结核性脑膜炎(结脑)中的意义及与预后的关系。方法测定发病2周内结脑组及对照组脑脊液中IFN-γ、I... 详细信息

目的应用间接酶联免疫吸附试验(enzyme-linked immunol sorbance assay,ELISA)检测脑脊液中炎症因子IFN-γ、IL-4的动态变化,探讨其在诊断结核性脑膜炎(结脑)中的意义及与预后的关系。方法测定发病2周内结脑组及对照组脑脊液中IFN-γ、IL-4含量及结脑组经抗结核治疗8周后脑脊液IFN-γ、IL-4含量。结果结脑组早期脑脊液IFN-γ、IL-4含量较对照组明显升高,经过抗结核治疗8周后47例明显下降,3例无下降者均为重症患者,2例合并脑梗死,1例合并脊髓损害肠梗阻。结论急性期脑脊液中IFN-γ、IL-4含量升高有助于结脑的诊断,其动态变化有助于判断结脑预后。

关键词：结核性脑膜炎脑脊液 IFN-γ、IL-4 诊断

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Mercury Content in Near-surface Ambient Air upon Typical Underground Coal Fire Zone and Spontaneous-ignited Gangue Hill

Mercury Content in Near-surface Ambient Air upon Typical Und...

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Environmental Pollution and Public Health(EPPH 2012)

作者： Handong Liang Yanci Liang xuwen He Shan Li Shanshan liu State Key Laboratory of Coal Resources and Safe Mining School of Chemical&Environmental Engineering China University of Mining and Technology Beijing School of Chemical & Environmental Engineering China University of Mining and Technology Beijing

To study the emission and diffusion pattern of mercury released from underground coal fire and spontaneous-ignited gangue hill, measurements were applied on the ambient air samples with 1.2m height to ground surface in the peripheral area of a typical underground coal fire zone in central Inner Mongolia in north China (central coordinates: 39°30′44″ N/106°37′05″E , altitude:1246.82m, total peripheral area: 25000m2) in a 10mx10m grid and at the vicinity of a spontaneous-ignited gangue hill (central coordinates: 39°34′16 ″ N/106°38′ 06″ E , area: 12000m2) 6.7km apart. Both measurements gave a prevalent mercury concentration of 40- 50ng/m3. The ground vapor measured in the drilling hole-0.4m to the surface in the vicinity of the gangue hill also provided mercury concentration at the same level. The result indicates mild mercury pollution in the near-surface ambient air in the studied mining area, which may be ascribed to long-term accumulation of low-dosed gaseous mercury emission from the underground coal fire and spontaneous-ignited gangue hill other than acute real-time mercury emission. The consistency in the mercury concentration of ambient air at two studied area 6.7km apart may bring new issue on the range of mercury diffusion at a concentration 30 times higher than atmospheric background level (1.6-1.8ng/m3) and its potential regional environmental, ecological and public health threat.

关键词： mercury emission underground coal fire gangue hill near surface air pollution Inner Mongolia

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A RETRIEVAL MODEL FOR QUESTION IN COMMUNITY QUESTION ANSWERING SYSTEM

A RETRIEVAL MODEL FOR QUESTION IN COMMUNITY QUESTION ANSWERI...

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2012 IEEE 2nd International Conference on Cloud Computing and Intelligence Systems

作者： Yueping Sun Xiaojie Wang Song liu Caixia Yuan xuwen Wang Center for Intelligence Science and Technology Research Beijing University of Posts and Telecommunications

Studies of Community-based question and answer services (cQA) have grown to be one of the emerging trends in Web information services. And one of the main tasks is to retrieve similar questions. To identify the fact that some questions with different expressions though may indeed have the same, or very similar, meaning, the similar questions are defined in syntactic, semantic and pragmatic aspects according to user retrieval intention. Five models including Language Model, Translation-based Language Model, Parser-based model, LDA and WordNet source-based model are selected as baselines. Integrated models which linearly combine WordNet, Stanford Parser and Language Model and further weighted by syntactic feature are proposed to integrate features of the three aspects. Experiment results show that our integrated models perform better than the basic models, especially when the linear combination of the WordNet model and the Stanford Parser model is weighted by syntactic information with proper noun phrases as representative. The integrated models are further verified by logistic analysis.

关键词： Community question answering system WordNet Language model Stanford parser Proper noun phrase

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Behavior of HVOF WC-10Co4Cr Coatings with Different Carbide Size in Fine and Coarse Particle Abrasion

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JOURNAL OF THERMAL SPRAY TECHNOLOGY 2010年第1-2期19卷 368-377页

作者： Ghabchi, Arash Varis, Tommi Turunen, Erja Suhonen, Tomi liu, xuwen Hannula, S. -P. Tech Res Ctr Finland VTT Espoo Finland Aalto Univ Dept Mat Sci & Engn FIN-02150 Espoo Finland SUNY Stony Brook Dept Mat Sci & Engn Ctr Thermal Spray Res Stony Brook NY USA

A modified ASTM G 65 rubber wheel test was employed in wet and dry conditions using 220 nm titania particles and 368 mu m sand particles, respectively. Both tests were conducted on WC-CoCr coatings produced with two powders with different carbide grain sizes (conventional and sub-micron) to address the effect of carbide size and abrasive medium characteristics on the wear performance. The same spot before and after the wet abrasion wear testing was analyzed in detail using SEM to visualize wear mechanisms. It was shown that the wear mechanism depends on the relative size of the carbide and abrasive particles. Wear mechanisms in dry sand abrasion were studied by analyzing the single scratches formed by individual abrasive particles. Interaction of surface open porosity with moving abrasive particles causes formation of single scratches. By tailoring the carbide size, the wear performance can be improved.

关键词： HVOF rubber wheel abrasion test WC-CoCr wear mechanism

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Behavior of HVOF WC-10Co4Cr Coatings with Different Carbide Size in Fine and Coarse Particle Abrasion

Behavior of HVOF WC-10Co4Cr Coatings with Different Carbide ...

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International Thermal Spray Conference (ITSC 2009)

关键词： HVOF rubber wheel abrasion test WC-CoCr wear mechanism

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水力负荷对潜流湿地去除污水处理厂二级出水中氮磷的影响

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水处理技术 2012年第8期38卷 118-121页

作者：王昊曹国凭何绪文杨永刘晓河北联合大学建筑工程学院河北唐山063009 中国矿业大学(北京)化学与环境工程学院北京100083

采用水平-石灰石、水平-沸石、垂直-沸石、垂直-改性沸石等4种潜流湿地对污水处理厂二级出水进行深度处理研究,探讨各系统稳定运行条件下,不同水力负荷对4种潜流湿地脱氮除磷效果的影响,以及4种湿地的去除污染物效果的差异性。结果表明... 详细信息

采用水平-石灰石、水平-沸石、垂直-沸石、垂直-改性沸石等4种潜流湿地对污水处理厂二级出水进行深度处理研究,探讨各系统稳定运行条件下,不同水力负荷对4种潜流湿地脱氮除磷效果的影响,以及4种湿地的去除污染物效果的差异性。结果表明,当进水水质为污水处理厂二级排放标准时,在一定的运行条件下,与垂直潜流湿地相比,水平潜流湿地对氮素的去除效果受水力负荷影响更大。其中,水平-沸石潜流湿地对NH3-N的去除率最高达到(96.5±2.58)%,而水平-石灰石潜流湿地最低仅为(78.7±3.64)%;水平-沸石潜流湿地对TN的去除率最高达到(94.5±2.58)%,最低仅为(66.1±2.02)%。另外,与水平流湿地相比,垂直流湿地对污水中磷素的去除效果较好,同时,垂直-沸石湿地表现出了对磷素最佳的去除效果,其对PO43--P的去除率最高达到(72.1±2.29)%,而对TP的去除率最高最高达到(73.8±3.25)%。此外,当水力负荷为0.093 m3/(m2.d)时,上述4种湿地对磷素均表现出了最佳的去除效果。

关键词：潜流湿地水力负荷污水处理厂二级出水氮磷

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抗虫棉与早熟陆地棉品种间产量及纤维品质性状的配合力分析

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西北农业学报 2012年第2期21卷 64-67页

作者：王娟刘丽孔宪辉王旭文余渝新疆农垦科学院棉花研究所农业部西北内陆区棉花生物学与遗传育种重点实验室新疆石河子832000

用5个早熟陆地棉品种作母本,3个抗虫棉品种作父本,按照不完全双列杂交设计(NCⅡ设计)组配15个杂交组合。对亲本及杂交组合的产量和纤维品质共11个性状进行配合力分析。结果表明,单株铃数、衣分、纤维长度、比强度、马克隆值和纤维伸长... 详细信息

用5个早熟陆地棉品种作母本,3个抗虫棉品种作父本,按照不完全双列杂交设计(NCⅡ设计)组配15个杂交组合。对亲本及杂交组合的产量和纤维品质共11个性状进行配合力分析。结果表明,单株铃数、衣分、纤维长度、比强度、马克隆值和纤维伸长率主要受基因加性效应控制,籽棉产量和皮棉产量主要受基因非加性效应影响。新陆早45号是突出的高衣分丰产亲本,新陆早48号是结铃性较好的丰产亲本,72-72是优良的抗虫棉亲本,组合新陆早48号×111-43和新陆早42号×N78在综合农艺性状上优势明显,但纤维品质相对而言没有明显改良。

关键词：抗虫棉不完全双列杂交农艺性状配合力

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9个早熟陆地棉新不育系主要性状配合力分析

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西北农业学报 2012年第11期21卷 90-95页

作者：刘丽孔宪辉王旭文王娟相吉山余渝新疆农垦科学院棉花研究所农业部西北内陆区棉花生物学与遗传育种重点实验室国家棉花改良中心新疆生产建设兵团分中心新疆石河子832000 新疆农垦科学院作物研究所谷物品质与遗传改良兵团重点实验室新疆石河子832000

为了进一步利用棉花杂种优势,促进三系杂交棉的选育,以哈克尼西棉、三裂棉(D8)和海岛棉(05-53A)3种胞质雄性不育系为母本,以新疆早熟陆地棉新陆早33号、新陆早36号和系9为回交亲本,连续回交4代,获得9(3×3)个新不育系(A1～A9);用3... 详细信息

为了进一步利用棉花杂种优势,促进三系杂交棉的选育,以哈克尼西棉、三裂棉(D8)和海岛棉(05-53A)3种胞质雄性不育系为母本,以新疆早熟陆地棉新陆早33号、新陆早36号和系9为回交亲本,连续回交4代,获得9(3×3)个新不育系(A1～A9);用3个恢复系(R1～R3)与新不育系进行杂交,获得27(9×3)个杂交组合。通过对8个性状配合力分析可知,A3、A4、A6和A9的籽棉产量,A3和A9的单株铃数,A2、A3和A9的铃质量,以及A4和A7的百粒质量的GCA效应值较高;A3×R1组合单株铃数、铃质量和A2×R1组合籽棉产量的SCA效应值最高;这些性状主要受亲本一般配合力和特殊配合力的共同影响,但一般配合力效应较特殊配合力的略大。对9个新不育系和3个恢复系进行亲本利用价值评价发现,A3、A9和R3有较大的利用价值。

关键词：细胞质雄性不育系配合力回交转育陆地棉

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Recent development of the magnetic shape memory materials research in Finland

Recent development of the magnetic shape memory materials re...

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作者： Söderberg, Outi Aaltio, Ilkka Ge, Yanling Soroka, Alexandr Niemi, Raisa liu, xuwen Hannula, Simo-Pekka Department of Materials Science and Engineering Helsinki University of Technology POB 6200 FI-02015 TKK Espoo Finland AdaptaMat Ltd. Yrityspiha 5 FI-00390 Helsinki Finland

ISBN: (纸本)9781617822018

Ni-Mn-Ga based magnetic shape memory (MSM) materials have been studied since 1998 in Finland at the Helsinki University of Technology (TKK, previously HUT). The large HUT-MSM-project resulted in MSM-alloys with high service temperature, 10 % field-induced-strain, as well as circumstances when and how a Ni-Mn-Ga alloy exhibits this phenomenon. The understanding of the structure and behavior of twin boundaries, and their role, for example, in the vibration damping and long-term actuation has been enhanced in the recent projects. Twin boundaries have been studied by XRD, by high-resolution transmission electron microscopy (HRTEM), and by in-situ straining in TEM, the last one in co-operation with the Institute of Physics in Prague (ASCR-IP), Czech Republic. The results obtained by neutron diffraction in co-operation with Hahn-Meitner-Institut Berlin, Institute for Metal Physics (IMP), Kiev, and Institut Laue-Langevin (ILL), Grenoble, have given new crystallographic information. Damping of Ni-Mn-Ga polymer composites has been proved to be excellent at high stiffness levels with the loss factor δ = 0.6 at E ≈ 1 GPa. This research was carried out in co-operation with the University of California Los Angeles (UCLA), USA. In the long-term actuation, a fatigue life of 2 × 109 has been recorded for a five-layered modulated Ni-Mn-Ga structure in mechanical cycling. The evolution of the MSM parameters during the long-term use is recorded and used as an input data for the models developed in the European MAFESMA co-operation. The search for alloys with wide stable thermal property range showing MSM effect has continued and alloys that are stable down to 4 K have been established. Modeling based on Ginsburg-Landau theory has been applied to evaluate aging and thermal fluctuations in the modulated Ni-Mn-Ga structures. As a commercial target, AdaptaMat Ltd. develops technology to produce Ni-Mn-Ga magnetic shape memory material with improved quality, lower twinning stress, longer fa

关键词： Damping

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