9-intersection model is the most popular framework used for formalizing the spatial relations between two spatial objectsA andB. It transforms the topological relationships between two simple spatial objectsA andB int...9-intersection model is the most popular framework used for formalizing the spatial relations between two spatial objectsA andB. It transforms the topological relationships between two simple spatial objectsA andB into point-set topology problem in terms of the intersections ofA’s boundary (?A), interior (A 0) and (A ?) withB’s boundary (?B), interior (B 0) and exterior (B ?). It is shown in this paper that there exist some limitations of the original 9-intersection model due to its definition of an object’s exterior as its complement, and it is difficult to distinguish different disjoint relations and relations between complex objects with holes, difficult or even impossible to compute the intersections with the two object’s complements (?A∩B ?,A 0∩?B ?,A ?∩?B,A ?∩B 0 andA ?∩B ?)since the complements are infinitive. The authors suggest to re-define the exterior of spatial object by replacing the complement with its Voronoi region. A new Voronoi-based 9-intersection (VNI) is proposed and used for formalizing topological relations between spatial bojects. By improving the 9-intersection model, it is now possible to distinguish disjoint relations and to deal with objects with holes. Also it is possible to compute the exterior-based intersections and manipulate spatial relations with the VNI.展开更多
目的:运用CRISPR/Cas9基因编辑技术构建前蛋白转化酶枯草溶菌素9(PCSK9)点突变家兔模型。方法:根据Pub Med基因蛋白数据对人和兔的PCSK9蛋白功能区进行Blast分析,发现人PCSK9基因的386S(丝氨酸)氨基酸功能区与兔PCSK9基因的485S同源。...目的:运用CRISPR/Cas9基因编辑技术构建前蛋白转化酶枯草溶菌素9(PCSK9)点突变家兔模型。方法:根据Pub Med基因蛋白数据对人和兔的PCSK9蛋白功能区进行Blast分析,发现人PCSK9基因的386S(丝氨酸)氨基酸功能区与兔PCSK9基因的485S同源。根据家兔PCSK9基因的485S对应的碱基替换位置及序列分析结果设计3条单链向导RNA和1条单链寡核苷酸供体模板。将合成的单链向导RNA、Cas9 m RNA和单链寡核苷酸供体共同注射入家兔受精卵细胞质内并将胚胎移植入待孕母兔体内。对获得的F0代兔进行PCR、TA克隆、脱靶检测以鉴定PCSK9S386A是否突变成功。利用获得的PCSK9S386A基因点突变家兔进行繁殖,扩大群体。结果:共获得15只F0代兔,其中1只为PCSK9S386A点突变纯合子,2只为PCSK9S386A点突变杂合子,且该突变可以稳定遗传。结论:利用CRISPR/Cas9技术成功构建了PCSK9S386A点突变家兔模型,为探究PCSK9功能减弱的分子机制,开发可靠、有效的诊断和治疗措施提供了良好的动物模型。展开更多
基金Project supported by the National Natural Science Foundation of China(No.49471059)
文摘9-intersection model is the most popular framework used for formalizing the spatial relations between two spatial objectsA andB. It transforms the topological relationships between two simple spatial objectsA andB into point-set topology problem in terms of the intersections ofA’s boundary (?A), interior (A 0) and (A ?) withB’s boundary (?B), interior (B 0) and exterior (B ?). It is shown in this paper that there exist some limitations of the original 9-intersection model due to its definition of an object’s exterior as its complement, and it is difficult to distinguish different disjoint relations and relations between complex objects with holes, difficult or even impossible to compute the intersections with the two object’s complements (?A∩B ?,A 0∩?B ?,A ?∩?B,A ?∩B 0 andA ?∩B ?)since the complements are infinitive. The authors suggest to re-define the exterior of spatial object by replacing the complement with its Voronoi region. A new Voronoi-based 9-intersection (VNI) is proposed and used for formalizing topological relations between spatial bojects. By improving the 9-intersection model, it is now possible to distinguish disjoint relations and to deal with objects with holes. Also it is possible to compute the exterior-based intersections and manipulate spatial relations with the VNI.
文摘目的:运用CRISPR/Cas9基因编辑技术构建前蛋白转化酶枯草溶菌素9(PCSK9)点突变家兔模型。方法:根据Pub Med基因蛋白数据对人和兔的PCSK9蛋白功能区进行Blast分析,发现人PCSK9基因的386S(丝氨酸)氨基酸功能区与兔PCSK9基因的485S同源。根据家兔PCSK9基因的485S对应的碱基替换位置及序列分析结果设计3条单链向导RNA和1条单链寡核苷酸供体模板。将合成的单链向导RNA、Cas9 m RNA和单链寡核苷酸供体共同注射入家兔受精卵细胞质内并将胚胎移植入待孕母兔体内。对获得的F0代兔进行PCR、TA克隆、脱靶检测以鉴定PCSK9S386A是否突变成功。利用获得的PCSK9S386A基因点突变家兔进行繁殖,扩大群体。结果:共获得15只F0代兔,其中1只为PCSK9S386A点突变纯合子,2只为PCSK9S386A点突变杂合子,且该突变可以稳定遗传。结论:利用CRISPR/Cas9技术成功构建了PCSK9S386A点突变家兔模型,为探究PCSK9功能减弱的分子机制,开发可靠、有效的诊断和治疗措施提供了良好的动物模型。
