滴灌技术结合节水灌溉制度可显著提高作物水分利用效率,但针对滴灌条件下冬小麦节水灌溉制度的优化研究相对较少,利用作物模型优化节水灌溉制度可以弥补田间试验的不足,对于作物精确灌溉具有重要的指导意义。本研究利用胶东冬小麦滴灌...滴灌技术结合节水灌溉制度可显著提高作物水分利用效率,但针对滴灌条件下冬小麦节水灌溉制度的优化研究相对较少,利用作物模型优化节水灌溉制度可以弥补田间试验的不足,对于作物精确灌溉具有重要的指导意义。本研究利用胶东冬小麦滴灌节水试验数据(2016—2019年)评价了根区水质模型(RZWQM-CERES)的适应性,并模拟评价了不同节水滴灌制度对冬小麦产量和水分利用效率的影响,以筛选最佳节水滴灌制度。结果表明RZWQM-CERES可以较好地模拟土壤水分、冬小麦生长和产量对不同滴灌处理和季节的响应,其中模拟0~90 cm土壤贮水量的均方根误差(RMSE)为22.7~32.3 mm、相对均方根误差(NRMSE)为11.9%~16.3%、决定系数(R2)为0.52~0.69,模拟收获期生物量的RMSE为1184~1904 kg hm-2、NRMSE为9.9%~16.8%、R2为0.67,模拟产量的RMSE为361~491 kg hm^(–2)、NRMSE为5.7%~7.8%、R2为0.75。长期模拟结果表明该地区冬小麦需水关键期为孕穗期(丰水年和平水年)或拔节期(枯水年)。针对不同降水年型冬小麦产量和水分利用效率对灌溉量的响应差异,筛选滴灌条件下冬小麦最佳灌溉制度为:丰水年在拔节期和开花期各灌水45mm;平水年(或枯水年)在拔节期、孕穗期及开花期各灌水35mm(或45 mm)。本研究结果扩展了RZWQM-CERES优化冬小麦滴灌制度的应用潜力,为实施冬小麦精确灌溉提供了重要的技术支持。展开更多
为了实时监控路网上移动对象(车辆)的运动,各移动对象不断向中心服务器汇报其位置,中心服务器存储数据以响应用户的各种查询。此类方法不仅通信开销巨大,增加服务器负载,而且不能同时满足群体态势感知和个体移动对象位置追踪的需求。因...为了实时监控路网上移动对象(车辆)的运动,各移动对象不断向中心服务器汇报其位置,中心服务器存储数据以响应用户的各种查询。此类方法不仅通信开销巨大,增加服务器负载,而且不能同时满足群体态势感知和个体移动对象位置追踪的需求。因此,提出一种基于时空锚点的双粒度移动感知(Double-granularity Movement Detection Based on Spatial-temporal Anchors,DMDSA)框架,将移动对象嵌入时空网格,其经过时空锚点时向服务器汇报其运动模式,实现对群体运动的感知和个体移动的追踪。离线阶段,服务器从历史轨迹中挖掘运动模式;移动对象运动时,服务器结合挖掘的运动模式,在线计算聚合模式表征群体运动,并采用最大似然估计确定目标的运动模式,实现群体态势感知;进一步,采用锚点独立策略和锚点序列策略识别最可能的运动序列,实时追踪个体对象的运动。在模拟数据集和实际数据集上的实验表明,所提方法在大幅度减小位置汇报代价的前提下,不仅能够准确地监控区域的群体运动态势,并且能够有效地追踪和预测个体移动对象的位置,有助于智慧城市的建设。展开更多
The sheep genome harbours approximately 20 copies of endogenous beta-retroviruses （enJSRVs）, and circumstantial evidence suggests that enJSRVs might play a role in mammalian reproduction, particularly placental morp...The sheep genome harbours approximately 20 copies of endogenous beta-retroviruses （enJSRVs）, and circumstantial evidence suggests that enJSRVs might play a role in mammalian reproduction, particularly placental morphogenesis. This study was aimed to assess the expression of mRNAs of an enJSRV and its receptor, HYAL2, in the uterus and conceptuses of Mongolian ewes throughout gestation, using real-time reverse transcription polymerase chain reaction and in situ hybridization analysis. The results showed that enJSRV and HYAL2 mRNAs were found to be expressed throughout gestation in the endometrium, chorion, placenta, and conceptus. The enJSRV mRNA was most abundant in the placenta on day 90 of pregnancy, in the endometrium on day 30 and 50, and in the chorion on day 70 and 110. However, HYAL2 mRNA was most abundant in the endometrium on day 30. These differences were all significantly different from each other （P〈0.01）. In situ hybridization showed that enJSRV and HYAL2 mRNAs were specifically expressed in endometrial luminal epithelium and glandular epithelium, trophoblastic giant binucleated cells （BNCs）, endometrial caruncles, placental cotyledons, stroma, trophectoderm, as well as multinucleated syncytia of the placenta and blood vessel endothelial cells. Collectively, little is known about the molecular mechanisms by which trophoblastic differentiation and multinucleated syncytia formation are regulated by enJSRVs. However, the temporal and spatial distributions of enJSRV expression in the uterus and conceptus indicate that differentiation of BNCs and the formation of a multinucleated syncytiotrophoblast involve enJSRV and possibly its cellular receptor, HYAL2. Therefore, enJSRV and HYAL2 appear to play important roles in the female reproductive physiology in this breed of sheep.展开更多
森林土器官的 N 用 N 小锚 X 光检查 absorptionnear 边结构(XANES ) 被调查在数量获得卓见进在 N 种形成和它的转变之间的关系。土壤样品在中央台湾从云杉，铁杉和松森林被收集。结果证明各种各样的器官的 N 类型能被 XANES 系列揭示...森林土器官的 N 用 N 小锚 X 光检查 absorptionnear 边结构(XANES ) 被调查在数量获得卓见进在 N 种形成和它的转变之间的关系。土壤样品在中央台湾从云杉，铁杉和松森林被收集。结果证明各种各样的器官的 N 类型能被 XANES 系列揭示。酰胺和 pyrrolic N 是在腐殖的物质，可溶的有机氮和原来的土壤的作文的主要部分。N 种形成的相对分发在处理和植被样品不同。云杉在可溶的有机氮(儿子) 从铁杉有重要差别在 402.3 eV 精力的系列达到顶点。在 A 地平线土壤，相对数量 ofpyridinic N 在 O 地平线土壤比那高得多，显示在在矿物质地平线的数量的 N 转变在器官的地平线与那不同，它可能在森林生态系统骑车的 N 起一个重要作用。展开更多
文摘滴灌技术结合节水灌溉制度可显著提高作物水分利用效率,但针对滴灌条件下冬小麦节水灌溉制度的优化研究相对较少,利用作物模型优化节水灌溉制度可以弥补田间试验的不足,对于作物精确灌溉具有重要的指导意义。本研究利用胶东冬小麦滴灌节水试验数据(2016—2019年)评价了根区水质模型(RZWQM-CERES)的适应性,并模拟评价了不同节水滴灌制度对冬小麦产量和水分利用效率的影响,以筛选最佳节水滴灌制度。结果表明RZWQM-CERES可以较好地模拟土壤水分、冬小麦生长和产量对不同滴灌处理和季节的响应,其中模拟0~90 cm土壤贮水量的均方根误差(RMSE)为22.7~32.3 mm、相对均方根误差(NRMSE)为11.9%~16.3%、决定系数(R2)为0.52~0.69,模拟收获期生物量的RMSE为1184~1904 kg hm-2、NRMSE为9.9%~16.8%、R2为0.67,模拟产量的RMSE为361~491 kg hm^(–2)、NRMSE为5.7%~7.8%、R2为0.75。长期模拟结果表明该地区冬小麦需水关键期为孕穗期(丰水年和平水年)或拔节期(枯水年)。针对不同降水年型冬小麦产量和水分利用效率对灌溉量的响应差异,筛选滴灌条件下冬小麦最佳灌溉制度为:丰水年在拔节期和开花期各灌水45mm;平水年(或枯水年)在拔节期、孕穗期及开花期各灌水35mm(或45 mm)。本研究结果扩展了RZWQM-CERES优化冬小麦滴灌制度的应用潜力,为实施冬小麦精确灌溉提供了重要的技术支持。
文摘为了实时监控路网上移动对象(车辆)的运动,各移动对象不断向中心服务器汇报其位置,中心服务器存储数据以响应用户的各种查询。此类方法不仅通信开销巨大,增加服务器负载,而且不能同时满足群体态势感知和个体移动对象位置追踪的需求。因此,提出一种基于时空锚点的双粒度移动感知(Double-granularity Movement Detection Based on Spatial-temporal Anchors,DMDSA)框架,将移动对象嵌入时空网格,其经过时空锚点时向服务器汇报其运动模式,实现对群体运动的感知和个体移动的追踪。离线阶段,服务器从历史轨迹中挖掘运动模式;移动对象运动时,服务器结合挖掘的运动模式,在线计算聚合模式表征群体运动,并采用最大似然估计确定目标的运动模式,实现群体态势感知;进一步,采用锚点独立策略和锚点序列策略识别最可能的运动序列,实时追踪个体对象的运动。在模拟数据集和实际数据集上的实验表明,所提方法在大幅度减小位置汇报代价的前提下,不仅能够准确地监控区域的群体运动态势,并且能够有效地追踪和预测个体移动对象的位置,有助于智慧城市的建设。
基金funded by the National Natural Science Foundation of China (30960271 and 31160493)the doctor fund project of Ministry of Education of China(20111515110008)
文摘The sheep genome harbours approximately 20 copies of endogenous beta-retroviruses （enJSRVs）, and circumstantial evidence suggests that enJSRVs might play a role in mammalian reproduction, particularly placental morphogenesis. This study was aimed to assess the expression of mRNAs of an enJSRV and its receptor, HYAL2, in the uterus and conceptuses of Mongolian ewes throughout gestation, using real-time reverse transcription polymerase chain reaction and in situ hybridization analysis. The results showed that enJSRV and HYAL2 mRNAs were found to be expressed throughout gestation in the endometrium, chorion, placenta, and conceptus. The enJSRV mRNA was most abundant in the placenta on day 90 of pregnancy, in the endometrium on day 30 and 50, and in the chorion on day 70 and 110. However, HYAL2 mRNA was most abundant in the endometrium on day 30. These differences were all significantly different from each other （P〈0.01）. In situ hybridization showed that enJSRV and HYAL2 mRNAs were specifically expressed in endometrial luminal epithelium and glandular epithelium, trophoblastic giant binucleated cells （BNCs）, endometrial caruncles, placental cotyledons, stroma, trophectoderm, as well as multinucleated syncytia of the placenta and blood vessel endothelial cells. Collectively, little is known about the molecular mechanisms by which trophoblastic differentiation and multinucleated syncytia formation are regulated by enJSRVs. However, the temporal and spatial distributions of enJSRV expression in the uterus and conceptus indicate that differentiation of BNCs and the formation of a multinucleated syncytiotrophoblast involve enJSRV and possibly its cellular receptor, HYAL2. Therefore, enJSRV and HYAL2 appear to play important roles in the female reproductive physiology in this breed of sheep.
基金This paper was supported by Front Project of Knowl-edge Innovation Program, Chinese Academy of Sciences (ISSASIP0205)
文摘森林土器官的 N 用 N 小锚 X 光检查 absorptionnear 边结构(XANES ) 被调查在数量获得卓见进在 N 种形成和它的转变之间的关系。土壤样品在中央台湾从云杉，铁杉和松森林被收集。结果证明各种各样的器官的 N 类型能被 XANES 系列揭示。酰胺和 pyrrolic N 是在腐殖的物质，可溶的有机氮和原来的土壤的作文的主要部分。N 种形成的相对分发在处理和植被样品不同。云杉在可溶的有机氮(儿子) 从铁杉有重要差别在 402.3 eV 精力的系列达到顶点。在 A 地平线土壤，相对数量 ofpyridinic N 在 O 地平线土壤比那高得多，显示在在矿物质地平线的数量的 N 转变在器官的地平线与那不同，它可能在森林生态系统骑车的 N 起一个重要作用。
