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Assessment of drought and its impact on winter wheat yield in the Chinese Loess Plateau

Journal of Arid Land 2022年第7期14卷 771-786页

作者： WANG fengjiao FU Bojie LIANG Wei JIN Zhao ZHANG Liwei YAN Jianwu FU Shuyi gou fen School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China National Demonstration Center for Experimental Geography Education Shaanxi Normal UniversityXi'an 710119China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F UniversityYangling 712100China School of Geography and Planning Sun Yat-Sen UniversityGuangzhou 510275China

Drought has pronounced and immediate impacts on agricultural production,especially in semi-arid and arid rainfed agricultural regions.Quantification of drought and its impact on crop yield is essential to agricultural water resource management and food security.We investigated drought and its impact on winter wheat(Triticum aestivum L.)yield in the Chinese Loess Plateau from 2001 to 2015.Specifically,we performed a varimax rotated principal component analysis on drought severity index(DSI)separately for four winter wheat growth periods:pre-sowing growth period(PG),early growth period(EG),middle growth period(MG),and late growth period(LG),resulting in three major subregional DSI dynamics for each growth period.The county-level projections of these major dynamics were then used to evaluate the growth period-specific impacts of DSI on winter wheat yields by using multiple linear regression analysis.Our results showed that the growth period-specific subregions had different major DSI dynamics.During PG,the northwestern area exhibited a rapid wetting trend,while small areas in the south showed a slight drying trend.The remaining subregions fluctuated between dryness and wetness.During EG,the northeastern and western areas exhibited a mild wetting trend.The remaining subregions did not display clear wetting or drying trends.During MG,the eastern and southwestern areas showed slight drying and wetting trends,respectively.The subregions scattered in the north and south had a significant wetting trend.During LG,large areas in the east and west exhibited wetting trends,whereas small parts in south-central area had a slight drying trend.Most counties in the north showed significant and slight wetting trends during PG,EG,and LG,whereas a few southwestern counties exhibited significant drying trends during PG and MG.Our analysis identified close and positive relationships between yields and DSI during LG,and revealed that almost all of the counties were vulnerable to drought.Similar but less strong relationships existed for

关键词： drought severity index winter wheat crop yield principal component analysis Loess Plateau

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Identification of Dominant Climate Variables on Spatiotemporal Variation in Reference Evapotranspiration on the Loess Plateau,China

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Chinese Geographical Science 2022年第4期32卷 620-642页

作者： LI Xiaofei LIANG Wei JIAO Lei YAN Jianwu ZHANG Weibin WANG fengjiao gou fen WANG Chengxi SHAO Quanqin School of Geography and Tourism Shaanxi Normal UniversityXi’an 710119China National Demonstration Center for Experimental Geography Education Shaanxi Normal UniversityXi’an 710119China Xi’an Gu Bo Electronic Intelligent Technology Co. LtdXi’anChina Key Laboratory of Terrestrial Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Reference evapotranspiration(ET_(0))is a vital component in hydrometeorological research and is widely applied to various aspects,such as water resource management,hydrological modeling,irrigation deployment,and understanding and predicting the influence of hydrologic cycle variations on future climate and land use changes.Quantifying the influence of various meteorological variables on ET_(0) is not only helpful for predicting actual evapotranspiration but also has important implications for understanding the impact of global climate change on regional water resources.Based on daily data from 69 meteorological stations,the present study analyzed the spatiotemporal pattern of ET_(0) and major contributing meteorological variables to ET_(0) from 1960 to 2017 by the segmented re-gression model,Mann-Kendall test,wavelet analysis,generalized linear model,and detrending method.The results showed that the annual ET_(0) declined slightly because of the combined effects of the reduction in solar radiation and wind speed and the increase in vapor pressure deficit(VPD)and average air temperature in the Loess Plateau(LP)during the past 58 yr.Four change points were detected in 1972,1990,1999,and 2010,and the annual ET_(0) showed a zigzag change trend of‘increasing-decreasing-increasing-decreasing-increasing’.Wind speed and VPD played a leading role in the ET_(0) changes from 1960 to 1990 and from 1991 to 2017,respectively.This study confirms that the dominant meteorological factors affecting ET_(0) had undergone significant changes due to global climate change and vegetation greening in the past 58 years,and VPD had become the major factor controlling the ET_(0) changes on the LP.The data presented herein will contribute to increasing the accuracy of predictions on future changes in ET_(0).

关键词： reference evapotranspiration(ET0) change points generalized linear model dominant factors vapor pressure deficit(VPD) Loess Plateau(LP)

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Assessing the impacts of natural conditions and human activities on terrestrial water storage in Loess Plateau,China

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Journal of Mountain Science 2023年第7期20卷 1921-1939页

作者： WANG Cheng-xi YAN Jian-wu LIANG Wei SUN Shao-bo gou fen LI Xiao-fei LUO Yuan-yuan WANG feng-jiao School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China National Demonstration Center for Experimental Geography Education Shaanxi Normal UniversityXi'an 710119China Institute of Surface-Earth System Science Tianjin UniversityTianjin 300072China

The gravity recovery and climate experiment(GRACE)has emerged as a crucial source of land water storage information in hydrological analysis and research.Numerous factors contribute to regional terrestrial water storage(TWS),resulting in a complex mechanism.In the Loess Plateau region,the continuous alteration of natural conditions and profound impact of human activities have posed a serious threat to the natural ecosystem,leading to an escalating trend of TWS reduction.Addressing the specific analysis of how natural conditions and human activities affect TWS represents a pressing issue.This study employed the residual analysis method to discern the contribution rates of natural conditions and human activities,elucidated the spatial and temporal changes associated with each factor,and ascertained their individual influence.The findings indicated that TWS on the Loess Plateau exhibited a downward trend of-4.89 mm·a^(-1)from 2003 to 2017.The combined effects of climate change and human activities accounted for alterations in water resource reserves across most areas of the Loess Plateau,with human activities predominantly driving these changes.Precipitation emerged as the primary natural factor influencing TWS variations,and NDVI demonstrated a positive feedback effect on TWS at approximately 30%.Substantial spatial disparities in TWS existed within the Loess Plateau,with human activities identified as the primary cause for the decreasing trend.Vegetation restoration plays a positive role in saving water resources in the Loess Plateau to some extent,and vegetation growth exceeding the regional load will lead to water shortage.

关键词： Terrestrial water storage Residual analysis Human activity the Loess Plateau

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乙烯利催熟对机采棉铃重和纤维品质的影响

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作物学报 2024年第1期50卷 209-218页

作者：刘韬奋罗单张启鹏孙圆圆李培松田景山张旺锋向导张亚黎杨明凤勾玲石河子大学农学院/新疆生产建设兵团绿洲生态农业重点实验室新疆石河子832003 石河子气象局乌兰乌苏农业气象试验站新疆石河子832003

催熟剂乙烯利的使用可实现机采棉提前吐絮和集中吐絮。本研究选择催熟剂敏感性和棉铃形态差异较大的18个棉花品种(材料),在棉铃发育不同阶段一次性喷施乙烯利,分析棉铃铃期缩短对棉花铃重和纤维品质的影响及其关系。结果表明,当棉铃铃期... 详细信息

催熟剂乙烯利的使用可实现机采棉提前吐絮和集中吐絮。本研究选择催熟剂敏感性和棉铃形态差异较大的18个棉花品种(材料),在棉铃发育不同阶段一次性喷施乙烯利,分析棉铃铃期缩短对棉花铃重和纤维品质的影响及其关系。结果表明,当棉铃铃期为47~69 d时,在棉铃铃龄40.5~49.7 d喷施乙烯利可使棉铃提前3.5~5.7 d吐絮。在乙烯利催熟下纤维完全发育成熟需64.1~69.7 d,棉籽则需54.8~60.5 d。棉铃吐絮时间提前1.5~6.2 d,铃重与纤维品质均降低的概率高达58.0%~76.5%。生产中可选择在棉铃铃龄34.8~44.1 d喷施乙烯利,此时棉株顶部棉铃铃重损失5%(损伤量<0.26g)、纤维品质损失1%(长度损伤量<0.28mm、断裂比强度损伤量<0.30cNtex–1),这是实现棉铃提前吐絮可接受的代价。此外,部分品种经催熟剂处理后棉铃铃期缩短但其铃重、纤维长度和断裂比强度均增加,此类情况的概率为9.5%~23.5%,说明部分机采棉品种适时使用乙烯利能够实现机采棉棉铃铃期缩短与提高铃重和纤维品质的协同。

关键词：棉花催熟单铃重纤维品质集中吐絮

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A review for cell-based screening methods in drug discovery

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Biophysics Reports 2021年第6期7卷 504-516页

作者： fen Wei Sicen Wang Xilan gou Health Science Center School of Pharmacy Xi’an Jiaotong University

With the biological relevance of the whole cells, low cost compared with animal experiments, a wide variety of cell-based screening platforms(cell-based assay, cell-based microfluidics, cell-based biosensor, cell-based chromatography) have been developed to address the challenges of drug discovery.In this review, we conclude the current advances in cell-based screening and summary the pros and cons of the platforms for different applications. Challenges and improvement strategies associated with cell-based methods are also discussed.

关键词： Cell-based screening Drug candidate Microfluidics Biosensor Affinity chromatography

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Micro RNA profiles and potential regulatory pattern during the early stage of spermatogenesis in mice

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Science China(Life Sciences) 2015年第11期58卷 442-450页

作者： LUO MengMeng HAO LiLi HU fen DONG YaNan gou LiXia ZHANG WenDian WANG Xin ZHAO YuHui JIA MengChun HU SongNian ZHANG XiuJun College of Life Sciences College of Psychology Hebei United University CAS Key Laboratory of Genome Sciences and Information Beijing Institute of Genomics Chinese Academy of Sciences Hebei Normal University for Nationalities Department of Reproductive Endocrinology National Research Institute for Family Planning

Spermatogenesis is a complicated and poorly understood process that relies on the precise regulation of the self-renewal and differentiation of spermatogonia. In many organisms, micro RNAs(mi RNAs) are involved in multiple developmental processes as critical regulators of transcriptional and post-transcriptional gene silencing. This study investigated the expression pattern of mi RNAs in type B spermatogonia cells(BSc) and primary spermatocytes(PSc) of mice, using a high-throughput small RNA sequencing system. The results revealed that the expression levels of Let-7 family mi RNAs were remarkably high in both cell types. Furthermore, the expression levels of mi R-21, mi R-140-3p, mi R-103, mi R-30 a, mi R-101 b and mi R-99 b were decreased during the transformation from BSc to PSc. These mi RNAs target vital genes that participate in apoptosis, cell proliferation and differentiation, junction assembly and cell cycle regulation. These results highlight the indispensable role of mi RNAs in spermatogenesis.

关键词：微小RNA 精子发生监管模式小鼠转录后基因沉默 miRNA 早期初级精母细胞

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Tree ring based streamflow reconstruction for the Upper Yellow River over the past 1234 years

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Chinese Science Bulletin 2010年第36期55卷 4179-4186页

作者： gou XiaoHua DENG Yang CHEN FaHu YANG MeiXue FANG KeYan GAO LinLin YANG Tao ZHANG fen Key Laboratory of Western China's Environmental Systems (MOE) Lanzhou University Lanzhou 730000 China State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

We established a Juniperus przewalski tree ring width chronology, based on tree ring cores collected from the A’nyêmaqên Mountains. Statistical analysis showed that the chronology was highly correlated with instrumental streamflow records from previous August to current July from the Tangnaihai Station in the upper reaches of the Yellow River, with a correlation coefficient of 0.656. Streamflow for the upper reaches of the Yellow River was reconstructed for the past 1234 years. Low flow periods for the 11-year averaged streamflow reconstruction were definite as lower than mean plus 1 standard deviation, and high flow periods were higher than mean minus 1 standard deviation. Over the past 1234 years, high flows occurred 18 times, and low flows occurred 12 times. The main low flow periods were identified as AD 1140–1156, AD 1295–1309, AD 1473–1500, and AD 1820–1847, and the main high flow periods were identified as AD 846–873, and AD 1375–1400. Extremely low streamflow over the reconstruction period was seen during the late 15th century, coinciding with a widespread drought phenomenon, which took place in the northeastern Tibetan Plateau over the same period. Reconstructed streamflow shows significant low-frequency variability, which is in line with drought variability of neighboring regions, as inferred from tree rings and other proxies. Multi-taper spectral analysis suggests the existence of significant periods of 2–5, 22, 35–38, 55–62, and 114–227 years, particularly significant for cyclic variations of years 159 and 36.

关键词：黄河上游径流量树木年轮干旱现象阿尼玛卿山低流量年轮宽度普氏原羚

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基于软件定义的WSNs非均匀分簇QoS路由算法

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计算机工程与科学 2022年第2期44卷 227-236页

作者：苟平章原晨张芬西北师范大学计算机科学与工程学院甘肃兰州730070

针对传统无线传感器网络非均匀分簇QoS路由中节点资源受限,无法动态管理等问题,提出一种基于软件定义的无线传感器网络非均匀分簇QoS路由算法(SDNUCQS)。控制器考虑节点能量、节点间距离和QoS指标,采用熵权法竞选出高质量簇头,并对网络... 详细信息

针对传统无线传感器网络非均匀分簇QoS路由中节点资源受限,无法动态管理等问题,提出一种基于软件定义的无线传感器网络非均匀分簇QoS路由算法(SDNUCQS)。控制器考虑节点能量、节点间距离和QoS指标,采用熵权法竞选出高质量簇头,并对网络进行非均匀分簇。利用交叉分类法将所要传输的数据通过时延和丢失率分成不同类型。在簇间路由中,控制器以链路QoS指标和节点负载度为参数,采用集中式方式分别计算QoS数据和普通数据传输的最佳路径。仿真实验结果表明,SDNUCQS算法能显著降低网络时延和丢失率,与LEACH、EEUC、CRIPSO和tPSOEB算法比较,能降低簇头能耗且延长了网络生命周期。

关键词：软件定义无线传感器网络非均匀分簇服务质量熵权法交叉分类

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美国贸易政策不确定性与跨境银行资本网络

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管理科学学报 2022年第9期25卷 108-126页

作者：李兴申谭小芬苟琴首都经济贸易大学经济学院北京100070 中央财经大学金融学院北京100081

在跨境银行资本流动网络视角下实证研究美国贸易政策不确定性对各国或地区之间跨境银行资本流动往来的影响,并考察宏观审慎政策的缓冲效果.基于2000年~2016年的103个经济体的季度面板数据回归,本文主要发现:第一,美国贸易政策不确定性... 详细信息

在跨境银行资本流动网络视角下实证研究美国贸易政策不确定性对各国或地区之间跨境银行资本流动往来的影响,并考察宏观审慎政策的缓冲效果.基于2000年~2016年的103个经济体的季度面板数据回归,本文主要发现:第一,美国贸易政策不确定性上升对跨境银行资本流动网络造成负向冲击,显著降低网络中各国资本流动的入度、加权入度、加权出度和加权度;第二,宏观审慎政策能够显著降低美国贸易政策不确定性带来的负向冲击;第三,贸易联系渠道和外汇风险暴露渠道是美国贸易政策不确定性影响跨境银行资本流动网络的重要渠道.本文还进一步从中美贸易摩擦事件、美国贸易政策不确定性的长期影响、不同类型宏观审慎政策的效果以及美国贸易政策不确定性的间接外溢影响角度,拓展了对美国贸易政策不确定性的分析.加深了对外部贸易政策不确定性冲击产生的潜在金融风险的理解,也为各国或地区防范和应对外部贸易政策不确定性风险冲击提供了理论依据.

关键词：美国贸易政策不确定性跨境银行资本流动宏观审慎政策网络模型

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Role of LM23 in cell proliferation and apoptosis and its expression during the testis development

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Asian Journal of Andrology 2013年第4期15卷 539-544,I0010页

作者： Qing Liu Ya-Juan Song Li-Jun Meng fen Hu Li-Xia gou Chang-Hong Jia Hong-Mei Tang Wei Jie Wang Mi Li Xiu-Jun Zhang Meng-Chun Jia College of Life Sciences Hebei United University Tangshan 063000 China Department of Clinical Laboratory Handan Central Hospital Handan 056002 China Department of Environment & Chemical Engineering Tangshan College Tangshan 063000 China and Department of Reproductive Endocrinology National Research Institute for Family Planning Beijing 100081 China

LM23, a gene expressed specifically in the testis in a stage-specific manner, has a diverse range of functions that are important in both the life and death of spermatogenic cells. The aim of this study was to further investigate the expression of LM23 in the developing rat testis and the biological function of LM23 in proliferation and antiapoptosis in vitro. Semiquantitative reverse transcription （RT）-PCR and real-time PCR were used to examine the expression of LM23 in testis at different developmental stages. The results suggested that LM23 mRNA levels in the testis increased progressively after birth. The role of LM23 in proliferation was analyzed with cell counting kit-8 （CCK8）, colony-forming efficiency （CFE） and flow cytometry assays. The results indicated that ectopic expression of LM23 in 293T cells significantly promoted cell proliferation by increasing cell numbers in S phase. Several methods were used, including CCK8, annexin V and propidium iodide staining and western blotting, to determine the role of LM23 in apoptosis. The results showed that LM23 played a protective role in H202-induced apoptosis of 293T cells, mediated at least in part through the Akt/PI3K signal pathway. Taken together, these results provide new insights into the role of LM23 in the development of the testes andspermatogenesis.

关键词： apoptosis LM23 proliferation rat testis

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