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Risk factors for mortality after coronary artery bypass grafting in patients with low left ventricular ejection fraction

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Chinese Medical Journal 2007年第4期120卷 317-322页

作者： WANG Jin xiao feng ren Jian LI Yan ZHANG Ming-li Department of Cardiac Surgery Peking University First Hospital Beijing 100034 China

Background We managed to assess and confirm the risk factors for mortality after coronary artery bypass grafting （CABG） operations so as to map out the proper guidance of surgical strategy especially in patients with low left ventncular ejection fraction （LVEF） in domestic polyclinic like ours. Methods Five hundred and forty-eight consecutive patients underwent CABG from December 1999 through August 2005 were analyzed retrospectively. Eighty-nine cases had an LVEF of 40% or less. All together twenty-two candidate factors were evaluated for their association with perioperative death using univariate and multivariate stepwise Logistic analysis. Results When data from all the patients who had undergone CABG were taken into account, LVEF, left ventricular end diastolic diameter （LVEDD）, mitral regurgitation, aneurysm of the heart wall, mitral repair/replacement, resection of aneurysm, concomitant aortic valve replacement, and perioperative intra-aortic balloon counter-pulsation （IABP）, left ventricular assist device （LVAD） and cardiopulmonary bypass （CPB） all showed an association with perioperative death in univariate analysis, while an LVEF of 〉40%, on the other hand, appeared to be a protective factor. In multivariate analysis, moderate to severe mitral regurgitation, aneurysm of the heart wall, repair of septal perforation and aortic regurgitation were proved to be risk factors. When the analysis was restricted to patients with an LVEF of 40% or less, such variables as age, LVEDD, mitral regurgitation, mitral repair/replacement, IABP, and CPB were qualified as risk factors in a univariate analysis. Age, moderate mitral regurgitation, aneurysm of the heart wall, CPB, left main coronary artery disease and female were associated with pefioperative death in a multivariate logistic regression analysis. Conclusions Concerning the prognosis, patients who undergo CABG would have different risk factors when data from all the enrolled patients or data from patients with

关键词： ventricular dysfunction, left coronary artery bypass risk factors

High summer background O_(3)levels in the desert of northwest China

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Journal of Environmental Sciences 2025年第5期151卷 516-528页

作者： Xinbing ren Fang Wang Bayi Wu Shaoting Zhang Lei Zhang Xingjun Zhou Yuanzhe ren Yongjing Ma feng Hao Yongli Tian Jinyuan Xin Key Laboratory of Atmospheric Environment and Extreme Meteorology Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Inner Mongolia Environmental Monitoring Center Alashan Substation 750300China Inner Mongolia Environmental Monitoring Center Hohhot 010011China Laboratory for Supervision and Evaluation of Pollution Reduction and Carbon Reduction in Arid and Semi-Arid Regions Inner Mongolia Environmental Monitoring CenterHohhot 010011China

Generally speaking,the precursors of ozone(O_(3)),nitrogen oxides and volatile organic compounds are very low in desert areas due to the lack of anthropogenic emissions and natural emissions,and thus O_(3)concentrations are relatively ***,high summer background concentrations of about 100μg/m^(3)or 60 ppb were found in the Alxa Desert in the highland of northwest China based on continuous summer observations from 2019 to 2021,which was higher than the most of natural background areas or clean areas in world for summer O_(3)background *** high O_(3)background concentrations were related to surface features and ***-intensity anthropogenic activity areas in desert areas can cause increased O_(3)concentrations or pollution,but also generated O_(3)depleting substances such as nitrous oxide,which eventually reduced the regional O_(3)baseline *** dioxide(NO2)also had a dual effect on O_(3)generation,showing promotion at low concentrations and inhibition at high *** addition,sand-dust weather reduced O_(3)clearly,but O_(3)eventually stabilized around the background concentration values and did not vary with sand-dust particulate matter.

关键词： Alxa Desert O_(3)background concentration Anthropogenic effect Sand-dust weather Northwest China

Carbody sway behaviour of railway vehicles due to track irregularity from rail alternate side wear

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Railway Engineering Science 2025年第1期33卷 27-42页

作者： Lai Wei Jing Zeng ren Luo feng Gan Jijun Gong Jun Jiang State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China China Railway Materials Operation and Maintenance Technology Co.Ltd. Beijing 100071China

Track irregularity from rail alternate side wear is manifested as uneven rail wear waveforms alternating in the left and right rails with equal intervals,which will cause carbody sway behaviour of railway vehicles and greatly influences the passenger *** this work,the carbody sway behaviour and mechanism due to track irregularity from rail alternate side wear and possible solutions to this issue were studied by the field testing and numerical calculation ***,the carbody sway of an urban rail transit train is introduced with full-scale field tests,through which the rail alternate side wear is characterized and the formatted track irregularity are ***,multibody vehicle dynamic models are developed to reproduce the carbody sway behaviour induced by the track irregularity from the rail alternate side *** creep forces acting on the wheel and rail are preliminarily discussed to study the influence of the carbody sway on the wear of the wheel flange and the rail ***,some potential solutions,*** the damping ratio of carbody rigid mode and rail grinding,are proposed to relieve this *** is concluded that an increased damping ratio of the carbody mode can alleviate the carbody sway and wheel–rail interactions,while properly maintaining track conditions can improve the vehicle performance.

关键词： Carbody sway Track irregularity Rail wear Creep force Carbody mode

Effect of graphene addition on activation and kinetic properties of La-Mg-Ni-based hydrogen storage alloys

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Journal of Iron and Steel Research International 2025年第1期32卷 227-238页

作者： Dian-chen feng Chun-ling Zheng Zhi-yuan Zhao Dong-sheng Zhou Hui-ping ren Yang-huan Zhang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou014010Inner MongoliaChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou014010Inner MongoliaChina Department of Functional Material Research China Iron and Steel Research Institute GroupBeijing100081China

The La_(1.7)Pr_(0.3)Mg_(16)Ni hydrogen storage alloy was prepared by medium-frequency induction melting,and then the composite hydrogen storage alloy powder of La_(1.7)Pr_(0.3)Mg_(16)Ni+x wt.%(x=0,2,4,and 6)graphene was prepared by ball milling for 10 *** effect of the addition of graphene on the activation and hydrogen de/absorption properties of La_(1.7)Pr_(0.3)Mg_(16)Ni alloy was *** result demonstrated that these composite alloys were composed of La_(2)Mg_(17),La_(2)Ni_(3),and Mg_(2)Ni *** saturated hydrogen absorption,it was composed of LaH_(3),Mg_(2)NiH_(4),and MgH_(2)phases,while during the dehydrogenation process,it was composed of LaH_(3),Mg,and Mg_(2)Ni *** addition of graphene can help get a more homogeneous granule after ball milling and accelerate the first activation of dehydrogenation/hydrogen *** hydrogen release activation energy of the alloys first decreases and then increases as the graphene content increases from x=0 wt.%to x=6 wt.%.The minimum activation energy of the composite hydrogen storage alloy is 51.22 kJ mol^(-1) when x=4 wt.%.

关键词： La-Mg-Ni alloy Graphene Mechanical ball milling Activation property Dynamic performance

Dual roles of the sacrificial agent in efficient solar-to-chemical production by nonphotosynthetic Moorella thermoacetica

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Science China Chemistry 2025年

作者： Rui Bai Junpeng Li Wei Chen Yi He Xudong Zhou xiaochun Tian Chongyuan ren Liqi Chen Yong xiao feng Zhao CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban Environment Chinese Academy of Sciences University of Chinese Academy of Sciences College of Chemistry and Chemical Engineering Xiamen University

The integration of microorganisms and photosensitizers presents a promising approach to chemical production utilizing solar energy. However, the current system construction process remains complex. Herein, we introduce a straightforward and efficient solar-to-chemical conversion system that combines the dissolved photosensitizer Eosin Y with the non-photosynthetic bacterium Moorella thermoacetica. Under light radiation, acetate production increased to 5.1 μM h-1μM-1catalyst, exceeding the previously reported maximum by 5.9-fold, with a quantum efficiency of 17.6%. The soluble photosensitizer EY can penetrate the cell and directly engage in intracellular energy metabolism, significantly enhancing intracellular ATP and NADPH/NADP+levels. Within this biohybrid system, sacrificial agent triethanolamine played a dual role:（1） providing continuous photoelectron generation by Eosin Y, enhancing intracellular reducing power, and facilitating carbon fixation via the Wood-Ljungdahl pathway; and（2） its oxidation product, formaldehyde, served as a critical intermediate and a direct precursor for methylenetetrahydrofolate in the Wood-Ljungdahl pathway, consequently simplifying reaction steps and markedly boosting acetate *** study provides a simple microorganism-photosensitizer biohybrid system to produce acetate and light on the multifaceted roles of sacrificial agents, paving the development of efficient solar energy conversion with nonphotosynthetic bacteria.

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Curcumin attenuates ochratoxin A and hypoxia co‑induced liver injury in grass carp(Ctenopharyngodon idella)by dual targeting endoplasmic reticulum stress and apoptosis via reducing ROS content

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Journal of Animal Science and Biotechnology 2025年第1期16卷 408-423页

作者： Liangqin Wu Piao Zhao Pei Wu Weidan Jiang Yang Liu Hongmei ren xiaowan Jin xiaoqiu Zhou Lin feng Animal Nutrition Institute Sichuan Agricultural UniversityChengdu 611130China Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province Sichuan Agricultural UniversityChengdu 611130China Key Laboratory of Animal Disease-Resistance Nutrition Ministry of EducationMinistry of Agriculture and Rural AffairsKey Laboratory of Sichuan ProvinceChengduSichuan 611130China

Background Ochratoxin A(OTA)is a toxin widely found in aquafeed ingredients,and hypoxia is a common prob-lem in fish *** practice,aquatic animals tend to be more sensitive to hypoxia while feeds are contaminated with OTA,but no studies exist in this *** research investigated the multiple biotoxicities of OTA and hypoxia combined on the liver of grass carp and explored the mitigating effect of curcumin(CUR).Methods A total of 720 healthy juvenile grass carp(11.06±0.05 g)were selected and assigned randomly to 4 experi-mental groups:control group(without OTA and CUR),1.2 mg/kg OTA group,400 mg/kg CUR group,and 1.2 mg/kg OTA+400 mg/kg CUR group with three replicates each for 60 ***,32 fish were selected,divided into nor-moxia(18 fish)and hypoxia(18 fish)groups,and subjected to hypoxia stress for 96 *** CUR can attenuate histopathological damage caused by coming to OTA and hypoxia by reducing vacu-olation and nuclear *** alleviation of this damage was associated with the attenuation of apoptosis in the mitochondrial pathway by decreasing the expression of the pro-apoptotic proteins Caspase 3,8,9,Bax,and Apaf1 while increasing the expression of the anti-apoptotic protein Bcl-2,and attenuation of endoplasmic reticulum stress(ERS)by reducing Grp78 expression and chop *** may be attributed to the fact that the addi-tion of CUR increased the levels of catalase(CAT)and glutathione reductase(GSH),increased antioxidant capacity,and ensured the proper functioning of respiratory chain complexes I and II,which in turn reduced the high produc-tion of reactive oxygen species(ROS),thus alleviating apoptosis and *** In conclusion,our data demonstrate the effectiveness of CUR in attenuating liver injury caused by the combination of OTA and *** study confirms the feasibility and efficacy of adding natural products to mitigate toxic damage to aquatic animals.

关键词： Apoptosis Curcumin Endoplasmic reticulum stress Grass carp Hypoxia Ochratoxin A Oxidative damage

Petrogenesis of late Cretaceous high Ba-Sr granodiorites,SE Lhasa block,China:implications for the reworking of juvenile crust and continental growth

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Acta Geochimica 2025年第1期44卷 86-111页

作者： Li-Hang Lin ren-Zhi Zhu Shao-Cong Lai Jiang-feng Qin Yu Zhu Shao-Wei Zhao Min Liu State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China Ministry of Education Key Laboratory of Western China’s Mineral Resources and Geological Engineering School of Earth Science and ResourcesChang’an UniversityXi’an 710054China

The high Ba-Sr rocks can provide significant clues about the evolution of the continent lithosphere,but their petrogenesis remains *** the Late Cretaceous high Ba–Sr granodiorites in the SE Lhasa Block could potentially provide valuable insights into the continent evolution of the Qinghai-Tibet *** U–Pb ages suggest that the granodiorites were emplaced at 87.32±0.43 ***,the high Ba–Sr granodiorites are characterized by elevated K_(2)O+Na_(2)O contents(8.18-8.73 wt%)and K_(2)O/Na_(2)O ratios(0.99-1.25,mostly>1),and belong to high-K calc-alkaline to shoshonitic *** Yonglaga granodiorites show notably high Sr(653-783 ppm)and Ba(1346-1531 ppm)contents,plus high Sr/Y(30.92-38.18)and(La/Yb)_(N)(27.7-34.7)ratios,but low Y(20.0-22.8 ppm)and Yb(1.92-2.19 ppm)contents with absence of negative Eu anomalies(δEu=0.83-0.88),all similar to typical high Ba–Sr *** variable zirconεHf(t)values of-4.58 to+12.97,elevated initial^(87)Sr/^(86)Sr isotopic ratios of 0.707254 to 0.707322 and lowεNd(t)values of-2.8 to-3.6 with decoupling from the Hf system suggest that a metasomatized mantle source included significant recycled ancient *** occurrence of such high Ba–Sr intrusions indicates previous contributions of metasomatized mantle-derived juvenile material to the continents,which imply the growth of continental crust during the Late Cretaceous in the SE *** with regional data,we infer that the underplated mafic magma provides a significant amount of heat,which leads to partial melting of the juvenile *** melting of the metasomatized mantle could produce a juvenile mafic lower crust,from which the high Ba–Sr granitoids were derived from reworking of previous mafic crust during the Late Cretaceous(ca.100-80 Ma)in the SE Lhasa.

关键词： Late Cretaceous High Ba-Sr granodiorites SE Lhasa Growth of continental crust Juvenile crust

基于GWR模型的陕西秦巴山区TRMM降水数据降尺度研究

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干旱区地理 2017年第1期40卷 26-36页

作者：曾昭昭王晓峰任亮陕西师范大学旅游与环境学院陕西西安710119

应用TRMM降水数据,进行国内典型区域降尺度相关研究,可弥补应用气象站点数据研究带来的局限。以陕西秦巴山区为研究区,基于TRMM降水数据和NDVI数据,应用GWR模型和比例指数,获得GWR年、月降尺度数据并进行检验,最后分析地形对降尺度结果... 详细信息

应用TRMM降水数据,进行国内典型区域降尺度相关研究,可弥补应用气象站点数据研究带来的局限。以陕西秦巴山区为研究区,基于TRMM降水数据和NDVI数据,应用GWR模型和比例指数,获得GWR年、月降尺度数据并进行检验,最后分析地形对降尺度结果的影响。结果表明:获得的1 km分辨率的GWR降尺度降水数据,具有较强的细节表现能力;降尺度数据与实测降水数据年尺度上相关系数为0.88,月为0.93,相关性较好;与TRMM原始数据对比,降尺度结果降水值略小,整体低估降水;区内秦岭山地GWR降尺度结果精度变化幅度最小,相似地形条件下,海拔越高,GWR降尺度结果表现越好;采用GWR模型进行秦巴山区TRMM降水数据的降尺度研究,具有较强的适用性。

关键词： TRMM降水数据 NDVI GWR模型降尺度陕西秦巴山区

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偶然、连续与模糊:纪录短片三题

宁波大学学报（人文科学版） 2023年第2期36卷 126-132页

作者：肖稔丰肖平南京航空航天大学艺术学院江苏南京210016

一分钟纪录短片即巴赞所倡导的镜头—段落和景深镜头,强调依赖摄影机镜头本身,而不是剪辑;倾向于景深镜头,追求长镜头的作用。纪录短片具有3个特征:即未经搬演的偶然事物、时间的连续性和含义模糊的多义性。纪录短片首先具有复制一切可... 详细信息

一分钟纪录短片即巴赞所倡导的镜头—段落和景深镜头,强调依赖摄影机镜头本身,而不是剪辑;倾向于景深镜头,追求长镜头的作用。纪录短片具有3个特征:即未经搬演的偶然事物、时间的连续性和含义模糊的多义性。纪录短片首先具有复制一切可见事物的能力,并且偏爱未经搬演的现实事物;第二,偶然的事物对于纪录短片来说,是一个特有的构成元素,意外事件要多于预先设置的事件,强调选择对象的真实;第三,时间的连续性,保证事件的时间进程得以呈现,强调时间空间的真实。事物意义含糊性和解释的不明确性,保留了未经加工的物质现实的多种含义,强调叙事结构的真实。纪录短片本质上是由那些未经搬演,偶然遭遇的具有某种因果联系的含义模糊的事物构成的,多义的场域是物质现实的本性,也体现在一分钟纪录短片中。纪录短片信守真实生活原貌中的暧昧与丰富,是一种镜头表达方式,也是一个事件,同时又是观看事件的反应与态度。

关键词：一分钟纪录短片偶然性连续性多义性