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Spatio-temporal variations of vegetation carbon use efficiency and potential driving meteorological factors in the Yangtze River Basin

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Journal of Mountain Science 2020年第8期17卷 1959-1973页

作者： ye xu-chun LIU Fu-hong ZHANG Zeng-xin xu Chong-yu LIU Jia Chongqing Key Laboratory of Karst Environment&School of Geographical Sciences of Southwest University Chongqing 400715China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Department of Geosciences University of Oslo N-0316Norway State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin Institute of Water Resources and Hydropower ResearchBeijing 100038China

Understanding of the vegetation dynamics is essential for addressing the potential threats of terrestrial *** recent years,the vegetation coverage of the Yangtze River Basin(YRB)has increased significantly,yet the spatio-temporal variations and potential driving meteorological factors of carbon use efficiency(CUE)under the context of global warming are still not *** this study,MODIS-based public-domain data during 2000–2015 was used to analyze these aspects in the YRB,a large river basin with powerful ecological functions in ***-temporal variations of CUE in different sub-basins and land cover types were investigated and the correlations with potential driving meteorological factors were *** revealed that CUE in the YRB had strong spatiotemporal variability and varied remarkably in different land cover *** the whole YRB,the average CUE of vegetated land was 0.519,while the long-term change trend of CUE was *** the rising altitude,CUE generally showed an increasing trend until the altitude of 3900 m and then followed by a decreasing *** of grasslands was generally higher than that of croplands,and then forest *** inter-annual variation of CUE in the YRB is likely to be driven by precipitation as a strong positive partial correlation between the inter-annual variability of CUE and precipitation was observed in most of sub-basins and land cover types in the *** influence of temperature and relative humidity is also outstanding in certain regions and land cover *** findings are useful from the view point of carbon cycle and reasonable land cover management under the context of global warming.

关键词： Carbon use efficiency Climate variability MODIS Altitude Land cover type Precipitation

A new class of HIV-1 inhibitors and the target identification via proteomic profiling

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Science China Chemistry 2018年第11期61卷 1430-1439页

作者： Ying-Zi Ge Bin Zhou Ruo-xuan Xiao Xiao-Jing Yuan Hu Zhou ye-chun xu Mark A.Wainberg Ying-Shan Han Jian-Min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Chinese Academy of Sciences McGill University AIDS Centre Lady Davis Institute for Medical Research Jewish General Hospital

Anti-HIV screening with the MT-4/MTT assay on a focused library of structurally diverse natural products has led to the discovery of a group of steroids with potent activities, which include four new ergostane-type steroids, named amotsterols A-D （1-4）, together with two known analogs. Among them, the most potent amotsterol D （4） exhibited anti-HIV activity against wild- type and some clinically relevant multidrug resistant HIV-I strains. Subsequent studies on its target identification through a proteomic approach found that compound 4 might target PKM2, a rate limiting enzyme ofglycolysis, in host cells to restrict HIV replication. The docking model of compound 4 to PKM2 showed that the two hydroxyl groups of 4 form hydrogen bonds with the two parallel Y390 in each subunit of PKM2 separately, and the ring C of 4 is sandwiched between the two parallel aromatic rings ofF26. The identified hit compound may have the potential to be further developed as a novel anti-HIVagent. These results demonstrated that an integrated approach, which combines new chemical structures and phenotypic screening with a proteomic approach, could not only identify novel HIV-1 inhibitors, but also elucidate the unknown targets of compound interactions in antiviral drug discovery.

关键词： ergostane-type steroids anti-HIV target identification PKM2

网格大小选择对大尺度分布式水文模型水文过程模拟的影响

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水土保持通报 2010年第3期30卷 112-116,127页

作者：叶许春张奇中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室中国科学院研究生院北京100049

以鄱阳湖信江流域为研究区,分析了网格大小选择对大尺度分布式水文模型水文过程模拟的影响。研究结果显示,在同样参数条件下,1,2和4km这3种不同尺寸网格对模拟的总径流量影响较小,但网格大小显著地改变着模拟水流在地表径流和地下径流... 详细信息

以鄱阳湖信江流域为研究区,分析了网格大小选择对大尺度分布式水文模型水文过程模拟的影响。研究结果显示,在同样参数条件下,1,2和4km这3种不同尺寸网格对模拟的总径流量影响较小,但网格大小显著地改变着模拟水流在地表径流和地下径流间的分配;不同网格的模型计算的实际蒸发量的差别不显著;大网格的模型计算的地下水补给量大。经过率定后的3种不同网格的模型均能较好地模拟流域的径流过程,但2km网格模型模拟的总体效果要好于1km网格模型和4km网格模型。研究表明,对于分布式水文模型,网格的精细并不一定提高模型的模拟效果,一定精度空间数据的输入条件下,分布式水文模型存在一个合适的网格大小使得模型的模拟效果最佳。在流域水文模型的具体应用中,应考虑流域本身的尺度以及模拟的目的和精度要求,选择合适的网格大小,同时应结合模型机理,解释模拟结果。

关键词：分布式水文模型网格大小径流实际蒸散发地下水补给鄱阳湖流域

The burden of upper motor neuron involvement is correlated with the bilateral limb involvement interval in patients with amyotrophic lateral sclerosis:a retrospective observational study

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Neural Regeneration Research 2025年第5期20卷 1505-1512页

作者： Jieying Wu Shan ye Xiangyi Liu Yingsheng xu Dongsheng Fan Department of Neurology Peking University Third HospitalBeijingChina Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases BeijingChina Key Laboratory for Neuroscience National Health Commission/Ministry of EducationPeking UniversityBeijingChina

Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor *** bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to ***,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is *** address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral *** used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis *** factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb *** results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis *** findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis.

关键词： amyotrophic lateral sclerosis bilateral limb involvement Cox proportional hazards regression model horizontal spread restricted cubic spline analysis time interval upper motor neuron vertical spread

土地利用变化对流域水文过程时空分异的影响——以赣江流域为例

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长江流域资源与环境 2020年第12期29卷 2747-2759页

作者：郭强叶许春刘佳刘福红西南大学地理科学学院重庆400715 中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100038

土地利用变化引起的水文分量时空变化对认识流域产汇流过程,优化流域土地利用结构和水资源规划具有重要意义。基于SWAT模型,本研究以赣江流域为例,结合1980、2000、2015年3期土地利用数据从水文响应单元的角度,系统分析了单纯土地利用... 详细信息

土地利用变化引起的水文分量时空变化对认识流域产汇流过程,优化流域土地利用结构和水资源规划具有重要意义。基于SWAT模型,本研究以赣江流域为例,结合1980、2000、2015年3期土地利用数据从水文响应单元的角度,系统分析了单纯土地利用变化对流域产流、蒸发、入渗以及径流等主要水文过程时空分布的影响。结果表明:1980~2015年间,流域内的土地利用变化主要表现为耕地和林地的减少,城乡建设用地的增加;林地的减少和城乡建设用地的增加是产流增加,蒸发和入渗减少的主要原因;总体上,土地利用变化对局部地区水文过程影响较大,但因土地利用类型之间的相互转化和其影响的叠加,流域尺度上的综合水文效应明显降低;土地利用变化导致整个赣江流域平均径流量增加了2.33×108m3,相比较近年来赣江径流的减小幅度其影响十分有限。近年来,赣江入湖径流量的下降主要是由气候变化和其他人类活动作用特别是流域工农业用水的大幅增长所致。流域水文过程模拟应充分考虑土地利用变化水文效应的时空分异,注重天然和社会水循环的耦合,才能更为真实的反映流域水文过程,更好的为流域土地利用结构优化和水资源的高效管理提供科学依据。

关键词：土地利用变化 SWAT模型水文过程时空分异赣江流域

老年痴呆相关蛋白靶标结构与功能关系的分子动力学模拟(英文)

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中国科学院研究生院学报 2009年第2期26卷 280-287页

作者：许叶春蒋华良中国科学院上海药物研究所药物发现与设计中心上海201203

主要运用常规和拉伸分子动力学模拟方法,研究β-淀粉样多肽的构象变化过程、乙酰胆碱酯酶和其抑制剂石杉碱甲的结合与解离过程,以及烟碱乙酰胆碱受体的离子门控构象变化过程,从而为老年痴呆症的病变机理,阐述和设计发现新的抗老年痴呆... 详细信息

主要运用常规和拉伸分子动力学模拟方法,研究β-淀粉样多肽的构象变化过程、乙酰胆碱酯酶和其抑制剂石杉碱甲的结合与解离过程,以及烟碱乙酰胆碱受体的离子门控构象变化过程,从而为老年痴呆症的病变机理,阐述和设计发现新的抗老年痴呆药物提供线索.

关键词：老年痴呆症分子动力学模拟 β-淀粉样多肽乙酰胆碱酯酶/石杉碱甲烟碱乙酰胆碱受体

鄱阳湖洪泛系统水位-面积迟滞关系的形成机制及演变

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长江流域资源与环境 2022年第10期31卷 2155-2165页

作者：吴娟张奇李云良叶许春西南大学地理科学学院重庆400715 中国科学院南京地理与湖泊研究所江苏南京210008 河海大学长江保护与绿色发展研究院江苏南京210024

鄱阳湖是连接长江的吞吐型湖泊,洪泛特征明显,湖泊水位和淹没面积的季节变化和空间差异悬殊,表现出高度的非线性特征。基于2000~2018年鄱阳湖区多源遥感数据和实测湖泊水位数据,采用ESTARFM (Enhanced Spatial and Temporal Adaptire Re... 详细信息

鄱阳湖是连接长江的吞吐型湖泊,洪泛特征明显,湖泊水位和淹没面积的季节变化和空间差异悬殊,表现出高度的非线性特征。基于2000~2018年鄱阳湖区多源遥感数据和实测湖泊水位数据,采用ESTARFM (Enhanced Spatial and Temporal Adaptire Reflectance Fusion Model)融合模型重构高时空分辨率淹水数据的方法,研究分析了鄱阳湖水位-面积迟滞关系形成机制与演变规律。结果表明:鄱阳湖水位-面积迟滞关系空间差异显著,同时存在逆时针和顺时针两种迟滞形式,其形成机制主要归因于湖泊上、下游表现出的河、湖相洪泛特征以及汇、排水过程的差异;鄱阳湖洪泛区广泛存在的碟形湖对增大鄱阳湖区上游站点迟滞度,减小下游迟滞度具有重要影响;近年来,受区域气候变化、湖区采砂活动以及三峡工程建成运行等造成的湖泊本身泄流能力和流域来水变化的影响,鄱阳湖区不同站点的水位-面积迟滞关系发生了显著变化。三峡工程多阶段实验性蓄水前后,以湖口、星子和都昌站为代表的北部湖区水位-面积关系迟滞度在2000~2003、2004~2009和2010~2018年分别呈现出先增大后减小的过程,而棠荫和康山站为代表的南部湖区则呈现出先减小后增大的过程。研究结果对于深化通江湖泊洪泛系统水文复杂性的认识、促进湖泊生态系统的管理实践具有重要的科学意义。

关键词：鄱阳湖水位-面积关系迟滞度 ESTARFM模型碟形湖

Perfluoropentane-based oxygen-loaded nanodroplets reduce microglial activation through metabolic reprogramming

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Neural Regeneration Research 2025年第4期20卷 1178-1191页

作者： Wanxian Luo Chuanhui xu Linxi Li Yunxiang Ji yezhong Wang Yingjia Li Yongyi ye Department of Medicine Ultrasonics Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina Institute of Neuroscience Department of NeurosurgeryThe Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina

Microglia,the primary immune cells within the brain,have gained recognition as a promising therapeutic target for managing neurodegenerative diseases within the central nervous system,including Parkinson’s *** perfluorocarbon droplets have been reported to not only possess a high oxygen-carrying capacity,but also exhibit remarkable anti-inflammatory ***,the role of perfluoropentane in microglia-mediated central inflammatory reactions remains poorly *** this study,we developed perfluoropentane-based oxygen-loaded nanodroplets(PFP-OLNDs)and found that pretreatment with these droplets suppressed the lipopolysaccharide-induced activation of M1-type microglia in vitro and in vivo,and suppressed microglial activation in a mouse model of Parkinson’s *** suppression led to a reduction in the inflammatory response,oxidative stress,and cell migration capacity in ***,the neurotoxic effects were mitigated,which alleviated neuronal ***,ultrahigh-performance liquid chromatography–tandem mass spectrometry showed that the anti-inflammatory effects of PFP-OLNDs mainly resulted from the modulation of microglial metabolic *** further showed that PFP-OLNDs regulated microglial metabolic reprogramming through the AKT-mTOR-HIF-1α***,our findings suggest that the novel PFP-OLNDs constructed in this study alleviate microglia-mediated central inflammatory reactions through metabolic reprogramming.

关键词： metabolic reprogramming microglia microglial migration nanotherapy neurodegenerative diseases neuroinflammation oxygen-loaded nanodroplets Parkinson’s disease perfluoropentane ultra-performance liquid chromatography–mass spectrometry

人-机任务情境下ICU护士工作体验的质性研究

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护理学报 2022年第16期29卷 6-10页

作者：闫妍叶旭春中国人民解放军海军军医大学护理系基础护理学教研室上海200433

目的深入了解ICU护士执行人-机任务时的工作体验,为促进新技术与护理专业发展深度融合提供参考。方法采用描述性现象学研究法,于2019年12月—2020年10月,对上海市4所三级甲等医院的14名ICU护士进行半结构式深入访谈,并运用Colaizzi 7步... 详细信息

目的深入了解ICU护士执行人-机任务时的工作体验,为促进新技术与护理专业发展深度融合提供参考。方法采用描述性现象学研究法,于2019年12月—2020年10月,对上海市4所三级甲等医院的14名ICU护士进行半结构式深入访谈,并运用Colaizzi 7步分析法对访谈资料进行分析。结果共提炼出4个主题:初始尝试时的抗拒与好奇;熟练掌握后的优势认可;非预期事件的烦躁慌乱;人机交互中的有效应对。结论护士普遍认可人-机任务普及的优势,但需关注非预期事件中的情绪反应,采取积极有效的应对方式。

关键词：人-机任务 ICU 护士工作体验质性研究