目的了解云南省边境民族地区中小学生的心理健康状况及其影响因素,为该地中小学生心理健康教育提供依据。方法采用分层整群随机抽样方法,于2023年8月至12月选取云南省边境8个市(州)的2728名4~9年级学生作为研究对象,使用中学生心理健康...目的了解云南省边境民族地区中小学生的心理健康状况及其影响因素,为该地中小学生心理健康教育提供依据。方法采用分层整群随机抽样方法,于2023年8月至12月选取云南省边境8个市(州)的2728名4~9年级学生作为研究对象,使用中学生心理健康量表(Mental Health Inventory of Middle-school Students,MMHI-60)和儿童多维焦虑量表中文版(Multidimensional Anxiety Scale for Children,MASC-C)对其心理健康状况进行调查。结果云南边境民族地区中小学生MMHI-60总均分阳性检出率为38.27%,其中轻度问题者为30.72%,中度者为6.74%,较重者为0.51%,严重者为0.29%;MASC-C阳性检出率为33.47%,轻度焦虑者占15.14%,中度焦虑者占8.72%,严重焦虑者占9.60%。分层分析表明,不同性别、民族、年级、户口类型、年龄、是否是独生子女和父母学历在学生心理问题检出率上的差异有统计学意义(P<0.05)。二元Logistic回归分析结果显示,年龄越大,有心理问题的比例越高,性别、傣族、哈尼族、傈僳族、六年级、母亲学历大学及以上均对4~9年级的学生心理健康有影响。结论云南边境民族地区中小学生心理健康水平处于中等水平,与其性别、年龄、年级、民族、户口类型、是否是独生子女、留守儿童、父母学历密切相关,亟待构建网格化心理健康服务管理体系,建立心理健康档案,重点关注离异家庭、留守儿童和边境农村贫苦地区学生的心理健康状况。展开更多
Due to the scale effect, the uniform distribution of reagents in continuous flow reactor becomes bad when the channel is enlarged to tens of millimeters. Microfluidic field strategy was proposed to produce high mixing...Due to the scale effect, the uniform distribution of reagents in continuous flow reactor becomes bad when the channel is enlarged to tens of millimeters. Microfluidic field strategy was proposed to produce high mixing efficiency in large-scale channel. A 3D spiral baffle structure(3SBS) was designed and optimized to form microfluidic field disturbed by continuous secondary flow in millimeter scale Y-shaped tube mixer(YSTM). Enhancement effect of the 3SBS in liquid-liquid homogeneous chemical processes was verified and evaluated through the combination of simulation and experiment. Compared with 1 mm YSTM, 10 mm YSTM with 3SBS increased the treatment capacity by 100 times, shortened the basic complete mixing time by 0.85 times, which proves the potential of microfluidic field strategy in enhancement and scale-up of liquid-liquid homogeneous chemical process.展开更多
An orientation of a graph G with even number of vertices is Pfaffian if every even cycle C such that G-V(C) has a perfect matching has an odd number of edges directed in either direction of the cycle. The significance...An orientation of a graph G with even number of vertices is Pfaffian if every even cycle C such that G-V(C) has a perfect matching has an odd number of edges directed in either direction of the cycle. The significance of Pfaffian orientations stems from the fact that if a graph G has one, then the number of perfect matchings of G can be computed in polynomial time. There is a classical result of Kasteleyn that every planar graph has a Pfaffian orientation. Little proved an elegant characterization of bipartite graphs that admit a Pfaffian orientation. Robertson, Seymour and Thomas (1999) gave a polynomial-time recognition algorithm to test whether a bipartite graph is Pfaffian by a structural description of bipartite graphs. In this paper, we consider the Pfaffian property of graphs embedding on the orientable surface with genus one (i.e., the torus). Some sufficient conditions for Pfaffian graphs on the torus are obtained. Furthermore, we show that all quadrilateral tilings on the torus are Pfaffian if and only if they are not bipartite graphs.展开更多
In this paper, we give the ordering of single-corner hexagonal chains with respect to Merrifield-Simmons index. At the same time, the hexagonal chain with the second largest Merrifield-Simmons index is also determined.
文摘目的了解云南省边境民族地区中小学生的心理健康状况及其影响因素,为该地中小学生心理健康教育提供依据。方法采用分层整群随机抽样方法,于2023年8月至12月选取云南省边境8个市(州)的2728名4~9年级学生作为研究对象,使用中学生心理健康量表(Mental Health Inventory of Middle-school Students,MMHI-60)和儿童多维焦虑量表中文版(Multidimensional Anxiety Scale for Children,MASC-C)对其心理健康状况进行调查。结果云南边境民族地区中小学生MMHI-60总均分阳性检出率为38.27%,其中轻度问题者为30.72%,中度者为6.74%,较重者为0.51%,严重者为0.29%;MASC-C阳性检出率为33.47%,轻度焦虑者占15.14%,中度焦虑者占8.72%,严重焦虑者占9.60%。分层分析表明,不同性别、民族、年级、户口类型、年龄、是否是独生子女和父母学历在学生心理问题检出率上的差异有统计学意义(P<0.05)。二元Logistic回归分析结果显示,年龄越大,有心理问题的比例越高,性别、傣族、哈尼族、傈僳族、六年级、母亲学历大学及以上均对4~9年级的学生心理健康有影响。结论云南边境民族地区中小学生心理健康水平处于中等水平,与其性别、年龄、年级、民族、户口类型、是否是独生子女、留守儿童、父母学历密切相关,亟待构建网格化心理健康服务管理体系,建立心理健康档案,重点关注离异家庭、留守儿童和边境农村贫苦地区学生的心理健康状况。
基金supported by the National Key Research and Development Program of China (2021YFC2101900 and 2019YFA0905000)National Natural Science Foundation of China (21908094, 21776130 and 22078150)+1 种基金Nanjing International Joint Research and Development Project (202002037)Top-notch Academic Programs Project of Jiangsu Higher Education Institutions。
文摘Due to the scale effect, the uniform distribution of reagents in continuous flow reactor becomes bad when the channel is enlarged to tens of millimeters. Microfluidic field strategy was proposed to produce high mixing efficiency in large-scale channel. A 3D spiral baffle structure(3SBS) was designed and optimized to form microfluidic field disturbed by continuous secondary flow in millimeter scale Y-shaped tube mixer(YSTM). Enhancement effect of the 3SBS in liquid-liquid homogeneous chemical processes was verified and evaluated through the combination of simulation and experiment. Compared with 1 mm YSTM, 10 mm YSTM with 3SBS increased the treatment capacity by 100 times, shortened the basic complete mixing time by 0.85 times, which proves the potential of microfluidic field strategy in enhancement and scale-up of liquid-liquid homogeneous chemical process.
基金National Natural Science Foundation of China (Grant Nos. 10831001 and 11171279)the Scientific Research Foundation of Zhangzhou Normal University (Grant No. SX1002)
文摘An orientation of a graph G with even number of vertices is Pfaffian if every even cycle C such that G-V(C) has a perfect matching has an odd number of edges directed in either direction of the cycle. The significance of Pfaffian orientations stems from the fact that if a graph G has one, then the number of perfect matchings of G can be computed in polynomial time. There is a classical result of Kasteleyn that every planar graph has a Pfaffian orientation. Little proved an elegant characterization of bipartite graphs that admit a Pfaffian orientation. Robertson, Seymour and Thomas (1999) gave a polynomial-time recognition algorithm to test whether a bipartite graph is Pfaffian by a structural description of bipartite graphs. In this paper, we consider the Pfaffian property of graphs embedding on the orientable surface with genus one (i.e., the torus). Some sufficient conditions for Pfaffian graphs on the torus are obtained. Furthermore, we show that all quadrilateral tilings on the torus are Pfaffian if and only if they are not bipartite graphs.
基金This research was supported by Fujian Education Committee Foundation.
文摘In this paper, we give the ordering of single-corner hexagonal chains with respect to Merrifield-Simmons index. At the same time, the hexagonal chain with the second largest Merrifield-Simmons index is also determined.
