2021年7月17—22日河南省发生了一次历史罕见的持续性强降水,造成了巨大的经济损失。目前极端降水预报仍是次季节气候预测研究的热点和难点。区域气候模式有着比全球模式更精细的空间分辨率和更为完善的物理过程参数化方案,为进一步提...2021年7月17—22日河南省发生了一次历史罕见的持续性强降水,造成了巨大的经济损失。目前极端降水预报仍是次季节气候预测研究的热点和难点。区域气候模式有着比全球模式更精细的空间分辨率和更为完善的物理过程参数化方案,为进一步提高中国次季节降水预报能力提供了新途径。使用区域气候模式CWRF(regional Climate-Weather Research and Forecasting model)对中国气象局全球气候模式次季节预测系统CMA_CPSv3(China Meteorological Administration Climate Prediction System version 3)的预报结果进行中国区域动力降尺度,分析了CWRF和CMA_CPSv3模式对河南省2021年7月17—22日持续性强降水的预测效果。结果表明,区域模式和全球模式预报的降水空间分布和量级存在明显差异。尽管两个模式都低估了此次强降水过程的降水量,但总体上CWRF模式预报的降水量更大且更好地捕捉到了降水的空间分布。CWRF模式自6月26和29日起报的降水预报明显好于同一起报日CMA_CPSv3模式的预报结果。与CMA_CPSv3预报相比,CWRF显著地改善了东亚低空风场和低空急流的预报。CWRF对低空急流和水汽通量输送方向的改善尤为明显,预报的水汽在山脉的迎风坡辐合,为降水提供了有利的水汽条件。同时CWRF更好地预报了郑州上空的垂直上升运动,这些改善都有利于CWRF模式对降水有更高的预报技巧。展开更多
The diarylpyrimidine(DAPY) compounds are important in the nonnucleoside reverse enzyme inhibitors. The present study is aimed at studying the three-dimensional quantitative structure-activity relationship(3D-QSAR) of ...The diarylpyrimidine(DAPY) compounds are important in the nonnucleoside reverse enzyme inhibitors. The present study is aimed at studying the three-dimensional quantitative structure-activity relationship(3D-QSAR) of DAPY inhibitors and their binding mode. We build a 3D-QSAR model involving 24 training DAPY inhibitors based on Topomer CoMFA, and 8 molecules are employed to validate the external predictive power of the model obtained. The multiple correlation coefficients of fitting, cross-validation and external validation were 0.979, 0.597 and 0.756, respectively. Topomer Search was employed as a tool for virtual screening in drug-like compounds of ZINC database(2012). Finally, we successfully design 30 new molecules with higher activity than that of all training and test inhibitors. The results indicated that Topomer CoMFA model had both favorable estimation stability and good predictive capability. Topomer Search technology could be effectively used to screen and design new compound, and had good predictive capability to guide the design of new Anti-HIV drugs. The molecular docking method was also used to study the interactions of these drugs by docking the ligands into HIV-1 reverse transcriptase active site, which revealed the likely bioactive conformations. This study showed extensive interactions between the DAPY derivatives and MET230, TRP229, PHE227, TYR318, TYR183, PRO95, GLY99, ILE100,TYR188, VAL106, TYR181, GLY190, GLU138, VAL179, THR139, ASN103 and LYS101 residues in the active site of HIV-1 reverse transcriptase. These results provide useful insights for the design of potent new inhibitors of HIV-1 reverse transcriptase.展开更多
在美国举办的游戏开发者大会上，微软发布了最新版的XNA Game Studio 4．0游戏开发工具。新版工具增加了对Windows Phone7 Series的支持。特别是新系统手机基于3DAPI的硬件加速和跨平台延续进度功能让Windows phone7开始引起手机玩家的...在美国举办的游戏开发者大会上，微软发布了最新版的XNA Game Studio 4．0游戏开发工具。新版工具增加了对Windows Phone7 Series的支持。特别是新系统手机基于3DAPI的硬件加速和跨平台延续进度功能让Windows phone7开始引起手机玩家的关注。展开更多
为探讨杂交三倍体泥鳅Misgurnus anguillicaudatus配子染色体组的构成,以杂交三倍体泥鳅(3n)与二倍体泥鳅(2n)为研究对象,配制2n♀×3n♂和3n♀×2n♂杂交组合,对杂交后代的胚胎染色体进行银染(Ag-NORs)、CMA_3/DA/DAPI三重荧...为探讨杂交三倍体泥鳅Misgurnus anguillicaudatus配子染色体组的构成,以杂交三倍体泥鳅(3n)与二倍体泥鳅(2n)为研究对象,配制2n♀×3n♂和3n♀×2n♂杂交组合,对杂交后代的胚胎染色体进行银染(Ag-NORs)、CMA_3/DA/DAPI三重荧光染色和染色体荧光原位杂交(Fluorescence in situ hybridization,FISH)等方面的研究。结果表明:两个杂交组合的杂交后代胚胎染色体有丝分裂中期分裂相中最高银染点数均为3个,位于中部着丝粒染色体(M1)的端部区域;在2n♀×3n♂和3n♀×2n♂杂交后代胚胎染色体有丝分裂中CMA3阳性部位有3个,位于中部着丝粒染色体(M1)的端部区域;将核糖体5.8S+28S r DNA定位在杂交后代胚胎染色体上,两种杂交组合均可检测到3簇杂交信号,位于中部着丝粒染色体(M1)的端部区域。研究表明,杂交三倍体泥鳅无论雌雄与二倍体泥鳅杂交所产生的后代染色体组构成均为3套染色体组,进而可推测,杂交三倍体泥鳅无论雌雄均可产生(1.5~2)n的配子,该结果为三倍体泥鳅配子染色体组成提供了细胞遗传学证据。展开更多
文摘2021年7月17—22日河南省发生了一次历史罕见的持续性强降水,造成了巨大的经济损失。目前极端降水预报仍是次季节气候预测研究的热点和难点。区域气候模式有着比全球模式更精细的空间分辨率和更为完善的物理过程参数化方案,为进一步提高中国次季节降水预报能力提供了新途径。使用区域气候模式CWRF(regional Climate-Weather Research and Forecasting model)对中国气象局全球气候模式次季节预测系统CMA_CPSv3(China Meteorological Administration Climate Prediction System version 3)的预报结果进行中国区域动力降尺度,分析了CWRF和CMA_CPSv3模式对河南省2021年7月17—22日持续性强降水的预测效果。结果表明,区域模式和全球模式预报的降水空间分布和量级存在明显差异。尽管两个模式都低估了此次强降水过程的降水量,但总体上CWRF模式预报的降水量更大且更好地捕捉到了降水的空间分布。CWRF模式自6月26和29日起报的降水预报明显好于同一起报日CMA_CPSv3模式的预报结果。与CMA_CPSv3预报相比,CWRF显著地改善了东亚低空风场和低空急流的预报。CWRF对低空急流和水汽通量输送方向的改善尤为明显,预报的水汽在山脉的迎风坡辐合,为降水提供了有利的水汽条件。同时CWRF更好地预报了郑州上空的垂直上升运动,这些改善都有利于CWRF模式对降水有更高的预报技巧。
基金supported by the National Natural Science Foundation of China(21475081,21275094)the Graduate Innovation Fund of Shaanxi University of Science and Technology
文摘The diarylpyrimidine(DAPY) compounds are important in the nonnucleoside reverse enzyme inhibitors. The present study is aimed at studying the three-dimensional quantitative structure-activity relationship(3D-QSAR) of DAPY inhibitors and their binding mode. We build a 3D-QSAR model involving 24 training DAPY inhibitors based on Topomer CoMFA, and 8 molecules are employed to validate the external predictive power of the model obtained. The multiple correlation coefficients of fitting, cross-validation and external validation were 0.979, 0.597 and 0.756, respectively. Topomer Search was employed as a tool for virtual screening in drug-like compounds of ZINC database(2012). Finally, we successfully design 30 new molecules with higher activity than that of all training and test inhibitors. The results indicated that Topomer CoMFA model had both favorable estimation stability and good predictive capability. Topomer Search technology could be effectively used to screen and design new compound, and had good predictive capability to guide the design of new Anti-HIV drugs. The molecular docking method was also used to study the interactions of these drugs by docking the ligands into HIV-1 reverse transcriptase active site, which revealed the likely bioactive conformations. This study showed extensive interactions between the DAPY derivatives and MET230, TRP229, PHE227, TYR318, TYR183, PRO95, GLY99, ILE100,TYR188, VAL106, TYR181, GLY190, GLU138, VAL179, THR139, ASN103 and LYS101 residues in the active site of HIV-1 reverse transcriptase. These results provide useful insights for the design of potent new inhibitors of HIV-1 reverse transcriptase.
文摘为探讨杂交三倍体泥鳅Misgurnus anguillicaudatus配子染色体组的构成,以杂交三倍体泥鳅(3n)与二倍体泥鳅(2n)为研究对象,配制2n♀×3n♂和3n♀×2n♂杂交组合,对杂交后代的胚胎染色体进行银染(Ag-NORs)、CMA_3/DA/DAPI三重荧光染色和染色体荧光原位杂交(Fluorescence in situ hybridization,FISH)等方面的研究。结果表明:两个杂交组合的杂交后代胚胎染色体有丝分裂中期分裂相中最高银染点数均为3个,位于中部着丝粒染色体(M1)的端部区域;在2n♀×3n♂和3n♀×2n♂杂交后代胚胎染色体有丝分裂中CMA3阳性部位有3个,位于中部着丝粒染色体(M1)的端部区域;将核糖体5.8S+28S r DNA定位在杂交后代胚胎染色体上,两种杂交组合均可检测到3簇杂交信号,位于中部着丝粒染色体(M1)的端部区域。研究表明,杂交三倍体泥鳅无论雌雄与二倍体泥鳅杂交所产生的后代染色体组构成均为3套染色体组,进而可推测,杂交三倍体泥鳅无论雌雄均可产生(1.5~2)n的配子,该结果为三倍体泥鳅配子染色体组成提供了细胞遗传学证据。
