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Enantioseparation of Aminoglutethimide by High-speed Countercurrent Chromatography Using Carboxymethly-β-cyclodextrin as Chiral Selector

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Chinese Chemical Letters 2006年第6期17卷 787-790页

作者： Ping AI Jia Chuan liu Min ZI zhi hua DENG zhi Hong YAN Li Ming YUAN Department of Chemistry Yunnan Normal University Kunming 650092

Enantioseparation of aminoglutethimide was performed by high-speed counter-current chromatography with a two-phase system composed of ethyl acetate： methanol： water = 10： 1： 9. The lower phase contained 20 mmol/L of carboxymethly-β-cyclodextrin as chiral selector. The enantiomers were separated in 1.2 h and identified by chiral HPLC. This method was very efficient for the chiral preparative separation.

关键词： High speed countercurrent chromatography enantioseparation aminoglutethimide,carboxymethly-β-cyclodextrin.

Revealing climatic impacts on the temporal and spatial variation in vegetation activity across China:Sensitivity and contribution

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Advances in Climate Change Research 2021年第3期12卷 409-420页

作者： JIAO Ke-Wei GAO Jiang-Bo liu zhi-hua WU Shao-Hong Tamara L.FLETCHER Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang110016China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China

Relative weakness in sensitivity and contribution integration,especially lack of specific indicators at spatial and temporal scales,may hinder the formation of systematic knowledge for climate change impact on vegetation *** the interannual variability and periods difference,we investigated the ecosystem sensitivity to hydrothermal conditions and the contribution of individual climatic factors to vegetation activity on spatiotemporal scales during the period of 1980s—2013 in *** ran simulations of the Common Land Model(CoLM)to obtain the photosynthetic rate,and used the satellite-derived Normalized Difference Vegetation Index(NDVI),to which we applied a temporal sensitivity analysis,the slope change ratio of accumulative quantity(SCRAQ),and geographical *** show that the discrepancy between warming and precipitation variation contributed to vegetation activity was more notable than the ecosystem sensitivity to hydrothermal conditions,regardless of which temporal and spatial scale was *** sensitivity of vegetation activity to hydrothermal variation in most parts of northeastern and western China was higher than elsewhere,and the contribution of warming to vegetation dynamics was relatively high in the Inner Mongolian Plateau and Tibetan Plateau(>60%),where the contribution of warming to the vegetation distribution was also greater than elsewhere in ***,the contribution of precipitation variation to vegetation dynamics was comparatively greater in northwestern China and subtropical and tropical regions(>55%).The spatiotemporal contribution of precipitation variation to vegetation activity differed between regions,especially on the Tibetan Plateau and in subtropical and tropical ***,both the temporal and spatial sensitivities to climate change were weak in the subtropical and tropical regions,where the contribution of climatic factors to vegetation distribution was also ***,temperature sensit

关键词： Vegetation activity Climate change Sensitivity Contribution Spatial-temporal scales China

Concentration difference of auxin involved in stem development in soybean

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Journal of Integrative Agriculture 2020年第4期19卷 953-964页

作者： JIANG Zhen-feng liu Dan-dan WANG Tian-qiong LIANG Xi-long CUI Yu-hai liu zhi-hua LI Wen-bin Key Laboratory of Soybean Biology Ministry of Education/Soybean Research InstituteNortheast Agricultural UniversityHarbin 150030P.R.China College of Agronomy Heilongjiang Bayi Agricultural UniversityDaqing 163311P.R.China London Research and Development Center Agriculture and Agri-food CanadaLondon N5V 4T3Canada College of Resources and Environment Northeast Agricultural UniversityHarbin 150030P.R.China

Auxin regulates cell division and elongation of the primordial cells through its concentration and then shaped the plant architecture. Cell division and elongation form the internode of soybean and result in different plant heights and lodging resistance. Yet the mechanisms behind are unclear in soybean. To elucidate the mechanism of the concentration difference of auxin related to stem development in soybean, samples of apical shoot, elongation zone, and mature zone from the developing stems of soybean seedlings, Charleston, were harvested and measured for auxin concentration distributions and metabolites to identify the common underlying mechanisms responsible for concentration difference of auxin. Distribution of indole-3-acetic acid(IAA), indole-3-butyric acid(IBA), and methylindole-3-acetic acid(Me-IAA) were determined and auxin concentration distributions were found to have a complex regulation mechanism. The concentrations of IAA and Me-IAA in apical shoot were significantly different between elongation zone and mature zone resulting in an IAA gradient. Tryptophan dependent pathway from tryptamine directly to IAA or through indole-3-acetonitrile to IAA and from indole-3-propionic acid(IPA) to IAA were three primary IAA synthesis pathways. Moreover, some plant metabolites from flavonoid and phenylpropanoid synthesis pathways showed similar or reverse gradient and should involve in auxin homeostasis and concentration difference. All the data give the first insight in the concentration difference and homeostasis of auxin in soybean seedlings and facilitate a deeper understanding of the molecular mechanism of stem development and growth. The gathered information also helps to elucidate how plant height is formed in soybean and what strategy should be adopted to regulate the lodging resistance in soybean.

关键词： soybean concentration difference of auxin stem development metabolites

Potential impact of epidural labor analgesia on the outcomes of neonates and children

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Chinese Medical Journal 2020年第19期133卷 2353-2358页

作者： zhi-hua liu Dong-Xin Wang Department of Anesthesiology and Critical Care Medicine Peking University First HospitalBeijing 100034China.

This review summarizes recent evidences regarding the potential influences of epidural labor analgesia(ELA)on the outcomes of neonates and *** and relevant words including“ELA,”“ELA and neonatal outcomes,”“ELA and children’s development,”and“ELA and children’s neurocognitive development”were used to search articles published in PubMed database up to October *** articles and reviews regarding potential influences of ELA on neonates and children were *** references of the selected articles were also *** anesthetics used during ELA can be absorbed,enter the fetus,and produce neonatal depression;however,these effects are less severe than those during systematic opioid *** impact of anesthetic exposure during ELA on children’s neurodevelopment has not been fully studied,but would be mild if *** increases the risk of intrapartum maternal fever;the latter may be harmful to neonatal *** use of ELA may increase birth injury by increasing instrumental delivery,although long-term adverse events are *** the other hand,ELA may reduce maternal depression and,thus,produce favorable effects on neurocognitive development in childhood;but evidences are still lacking in this *** may produce both favorable and unfavorable effects on neonates and *** effects should be discussed with parturient women before making *** potential harmful effects should be carefully *** overall impacts of ELA on neonatal and children’s outcomes need to be studied further.

关键词： Epidural labor analgesia Neonates Children Outcomes

Effect of metoprolol on sarcoplasmic reticulum Ca^2＋ leak in a rabbit model of heart failure

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Chinese Medical Journal 2012年第5期000卷 815-822页

作者： ZHANG Shi-jie liu zhi-hua ZOU Cao WANG Lei Department of Laboratory MedicineFirst Affiliated Hospital of ZhengzhouUniversity Zhengzhou Henan 450052 China Department ofEmergency First Affiliated Hospital of ZhengzhouUniversity Zhengzhou Henan 450052 China Department of Cardiology First Affiliated Hospital of SoochowUniversity Suzhou Jiangsu 215006 China

Background Studies have shown that B-blockers can improve cardiac performance in heart failure （HF） by reversing protein kinase A （PKA）-mediated sarcoplasmic reticulum （SR） Ca^2＋ leak. However, it is being strongly questioned as to whether the PKA-mediated ryanodine receptor （RyR2） hyper-phosphorylation is a critical regulator of SR Ca^2＋ leak. In this study, we used a rabbit HF model to investigate whether β-blockers affect SR Ca^2＋ leak by other potential mechanisms.

关键词： β-blocker heart failure Ca^2+ leak ryanodine receptor phosphorylation

WSN中局部采样滤波的新颜色移动节点定位法

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电子与信息学报 2014年第10期36卷 2385-2392页

作者：刘志华张双河北师范大学信息技术学院石家庄050024

针对无线传感器网络(WSN)移动节点定位技术中的定位不精和实时性差的问题,该文提出一种局部采样、借助RGB差值序列滤波的新颜色移动定位LSF-CDL(Local Sampling and Filtering-Color Dynamic Localization)法。该算法利用收集的信号,在... 详细信息

针对无线传感器网络(WSN)移动节点定位技术中的定位不精和实时性差的问题,该文提出一种局部采样、借助RGB差值序列滤波的新颜色移动定位LSF-CDL(Local Sampling and Filtering-Color Dynamic Localization)法。该算法利用收集的信号,在与移动节点能直接通信的信标节点的信号交叠区域内局部采样;引入距离比例因子,对平均跳距权值化,优化了CDL中跳距的计算公式;借助RGB差值序列对样本点滤波并将差值序列绝对值作为加权标准计算移动节点的坐标。仿真结果表明与E-CDL(Efficient-Color-theory based Dynamic Localization),MCL(Monte Carlo Localization)等经典的移动节点定位算法比较,新算法定位误差减少了33%以上,具有较好的定位效果。

关键词：无线传感器网络移动节点定位颜色定位法局部采样 RGB差值序列

局部等厚度的共翼型舵对潜艇尾流场优化效果研究

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推进技术 2020年第7期41卷 1660-1669页

作者：翟朔刘志华海军工程大学舰船与海洋学院湖北武汉430033

潜艇桨盘面伴流的不均匀性是影响螺旋桨在工作时产生振动和噪声的关键因素,潜艇指挥台围壳和尾舵产生的马蹄涡是导致桨盘面伴流不均匀性的重要原因。为了抑制尾舵处形成的马蹄涡,设计了一种局部等厚度的共翼型舵,通过数值模拟研究了其... 详细信息

潜艇桨盘面伴流的不均匀性是影响螺旋桨在工作时产生振动和噪声的关键因素,潜艇指挥台围壳和尾舵产生的马蹄涡是导致桨盘面伴流不均匀性的重要原因。为了抑制尾舵处形成的马蹄涡,设计了一种局部等厚度的共翼型舵,通过数值模拟研究了其对尾流场不均匀性的改善效果。结果表明,局部等厚舵可以使尾流场相比非共翼型舵不均匀度下降40%以上,并且在相同舵角下舵力显著增大;安装局部等厚舵的同时在围壳处安装消涡片可以使不均匀度下降60%以上;减小局部等厚舵的最大厚度和增大首部曲率都可以进一步改善尾流场,且舵力不受损失。局部等厚舵形式简单,对尾流场和舵力改善效果显著。

关键词：潜艇舵尾流马蹄涡数值模拟

消涡整流片对潜艇马蹄涡的控制及其与辅翼效果的比较

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船舶力学 2011年第10期15卷 1102-1109页

作者：刘志华熊鹰海军工程大学船舶与动力学院武汉430033

潜艇桨盘面伴流是潜艇螺旋桨的进流,其周向均匀性与螺旋桨的振动与噪声直接相关。文章在阐明潜艇主附体结合部马蹄涡对潜艇伴流影响和消涡整流片的作用原理的基础上,针对SUBOFF模型的几何特点,设计了一套消涡整流片,运用分离涡方法计算... 详细信息

潜艇桨盘面伴流是潜艇螺旋桨的进流,其周向均匀性与螺旋桨的振动与噪声直接相关。文章在阐明潜艇主附体结合部马蹄涡对潜艇伴流影响和消涡整流片的作用原理的基础上,针对SUBOFF模型的几何特点,设计了一套消涡整流片,运用分离涡方法计算了消涡整流片对桨盘面速度分量周向不均匀性的抑制作用,并与辅翼的整流作用进行了比较,结果表明,消涡整流片效果相对较好,可使周向不均匀性下降50%～80%,且整流片的整流效果具有较好的稳定性。

关键词：消涡整流片潜艇马蹄涡辅翼尾流不均匀性

ZIC2 is downregulated and represses tumor growth via the regulation of STAT3 in breast cancer

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ZIC2 is downregulated and represses tumor growth via the reg...