目的了解2023年贵州省从江县人群土源性线虫感染现状,为该县土源性线虫病防控提供科学依据。方法将从江县按不同地理方位划分5个片区,各片区分别随机抽取1个乡(镇)的1个行政村作为调查点,每个调查点随机整群抽取200名近3个月未驱虫的常...目的了解2023年贵州省从江县人群土源性线虫感染现状,为该县土源性线虫病防控提供科学依据。方法将从江县按不同地理方位划分5个片区,各片区分别随机抽取1个乡(镇)的1个行政村作为调查点,每个调查点随机整群抽取200名近3个月未驱虫的常住居民作为调查对象。2023年采集调查对象粪便标本,采用改良加藤厚涂片法(1粪2检)检测虫卵,比较不同特征人群土源性线虫感染状况。根据每克粪便虫卵数(eggs per gram,EPG),将感染状况分为轻、中、重度感染并计算各类感染构成比。此外,采用问卷调查了解调查对象基本情况及家庭无害化厕所建设情况。结果共调查从江县5个调查点1001名调查对象,土源性线虫感染率为19.08%(191/1001);其中蛔虫、钩虫感染率分别为2.30%(23/1001)、1.90%(19/1001),均为轻度感染;蛲虫感染率为0.10%(1/1001);鞭虫感染率为15.78%(158/1001)。各调查村鞭虫感染率差异有统计学意义(χ^(2)=123.345,P<0.001),其中留架村鞭虫感染率最高(39.00%),其次为龙江村(18.00%);各年龄组人群鞭虫感染率差异有统计学意义(χ^(2)=166.050,P<0.001),其中10~19岁组最高(48.19%),其次是70岁以上组(14.53%)和50~59岁组(13.04%);各职业人群鞭虫感染率差异有统计学意义(χ^(2)=74.134,P<0.001),以中学生感染率最高(32.32%),其次是工人(民工)(10.34%)和农民(10.12%);不同文化程度人群鞭虫感染率差异有统计学意义(χ^(2)=28.761,P<0.001),以小学文化程度者最高(21.60%),其次为文盲(12.03%);不同民族人群鞭虫感染率差异有统计学意义(χ^(2)=42.193,P<0.001)。鞭虫轻、中、重度感染者构成比分别为76.58%(121/158)、14.56%(23/158)和3.16%(5/158),重度感染者均为小学生。在123户家庭中发现鞭虫感染者,其中27户(21.95%)家庭中有2名及以上家庭成员感染。问卷调查共收集有效问卷1001份,家中是、否建有无害化厕所者鞭虫感染率分别为14.69%(139/964)、34.55%(19/55),差异有统计学意义(χ^(2)=15.410,P<0.001)。结论2023年贵州省从江县人群土源性线虫感染率较高,其中鞭虫感染尤为严重,应将小学生、中老年农民、民工作为重点人群开展防控工作。展开更多
Electric towers of high voltage transmission lines are more exposed to natural lightning phenomena thanks to their high heights. These lines are crossed by powerful current sources to dissipate in the ground, which ca...Electric towers of high voltage transmission lines are more exposed to natural lightning phenomena thanks to their high heights. These lines are crossed by powerful current sources to dissipate in the ground, which can, at one time or another, create disturbances or other phenomena can be generated. This is why we have set ourselves the objective of studying the FDTD modeling of the influence of direct lightning strikes on the power transmitted by a High-Voltage power line. To do this, we have implemented Kirchhoff’s laws to model the power transmitted by a High-Voltage power line in a steady state. Calculating the electromagnetic field generated by lightning requires the lightning current along the channel and its spatiotemporal distribution, the bi-exponential models and that of engineers were chosen and used to reproduce the physical phenomena best. Several works have been published in the literature and various mathematical models are proposed, to study the filamentous nature of power lines which has led to a more flexible modelling, based on the transmission line model, associated with the field theory developed from Maxwell’s equations, which explain the interaction between a lightning wave and a power transmission line. The resolution of the line equations in the lightning shock regime was the subject of the FDTD method to obtain the results in the spatio-temporal domain. Through this research, we are interested in the study of the spatiotemporal distribution of the lightning current wave to model the radiated electromagnetic field and to examine the influence of the overvoltage induced by the atmospheric discharge on the transportable power of a High Voltage AC Transmission line, for good selective protection to illuminate the parasites. 2D simulations based on proposed models were developed as well as the verification of the consistency of the different models, by comparing the fractal dimensions of the results of our program with those of the figures obtained experimentally. The aspects developed in this article could have direct implications in practical applications in the engineering and design of high-voltage transmission systems.展开更多
文摘目的了解2023年贵州省从江县人群土源性线虫感染现状,为该县土源性线虫病防控提供科学依据。方法将从江县按不同地理方位划分5个片区,各片区分别随机抽取1个乡(镇)的1个行政村作为调查点,每个调查点随机整群抽取200名近3个月未驱虫的常住居民作为调查对象。2023年采集调查对象粪便标本,采用改良加藤厚涂片法(1粪2检)检测虫卵,比较不同特征人群土源性线虫感染状况。根据每克粪便虫卵数(eggs per gram,EPG),将感染状况分为轻、中、重度感染并计算各类感染构成比。此外,采用问卷调查了解调查对象基本情况及家庭无害化厕所建设情况。结果共调查从江县5个调查点1001名调查对象,土源性线虫感染率为19.08%(191/1001);其中蛔虫、钩虫感染率分别为2.30%(23/1001)、1.90%(19/1001),均为轻度感染;蛲虫感染率为0.10%(1/1001);鞭虫感染率为15.78%(158/1001)。各调查村鞭虫感染率差异有统计学意义(χ^(2)=123.345,P<0.001),其中留架村鞭虫感染率最高(39.00%),其次为龙江村(18.00%);各年龄组人群鞭虫感染率差异有统计学意义(χ^(2)=166.050,P<0.001),其中10~19岁组最高(48.19%),其次是70岁以上组(14.53%)和50~59岁组(13.04%);各职业人群鞭虫感染率差异有统计学意义(χ^(2)=74.134,P<0.001),以中学生感染率最高(32.32%),其次是工人(民工)(10.34%)和农民(10.12%);不同文化程度人群鞭虫感染率差异有统计学意义(χ^(2)=28.761,P<0.001),以小学文化程度者最高(21.60%),其次为文盲(12.03%);不同民族人群鞭虫感染率差异有统计学意义(χ^(2)=42.193,P<0.001)。鞭虫轻、中、重度感染者构成比分别为76.58%(121/158)、14.56%(23/158)和3.16%(5/158),重度感染者均为小学生。在123户家庭中发现鞭虫感染者,其中27户(21.95%)家庭中有2名及以上家庭成员感染。问卷调查共收集有效问卷1001份,家中是、否建有无害化厕所者鞭虫感染率分别为14.69%(139/964)、34.55%(19/55),差异有统计学意义(χ^(2)=15.410,P<0.001)。结论2023年贵州省从江县人群土源性线虫感染率较高,其中鞭虫感染尤为严重,应将小学生、中老年农民、民工作为重点人群开展防控工作。
文摘Electric towers of high voltage transmission lines are more exposed to natural lightning phenomena thanks to their high heights. These lines are crossed by powerful current sources to dissipate in the ground, which can, at one time or another, create disturbances or other phenomena can be generated. This is why we have set ourselves the objective of studying the FDTD modeling of the influence of direct lightning strikes on the power transmitted by a High-Voltage power line. To do this, we have implemented Kirchhoff’s laws to model the power transmitted by a High-Voltage power line in a steady state. Calculating the electromagnetic field generated by lightning requires the lightning current along the channel and its spatiotemporal distribution, the bi-exponential models and that of engineers were chosen and used to reproduce the physical phenomena best. Several works have been published in the literature and various mathematical models are proposed, to study the filamentous nature of power lines which has led to a more flexible modelling, based on the transmission line model, associated with the field theory developed from Maxwell’s equations, which explain the interaction between a lightning wave and a power transmission line. The resolution of the line equations in the lightning shock regime was the subject of the FDTD method to obtain the results in the spatio-temporal domain. Through this research, we are interested in the study of the spatiotemporal distribution of the lightning current wave to model the radiated electromagnetic field and to examine the influence of the overvoltage induced by the atmospheric discharge on the transportable power of a High Voltage AC Transmission line, for good selective protection to illuminate the parasites. 2D simulations based on proposed models were developed as well as the verification of the consistency of the different models, by comparing the fractal dimensions of the results of our program with those of the figures obtained experimentally. The aspects developed in this article could have direct implications in practical applications in the engineering and design of high-voltage transmission systems.
