Objective: To explore the current situation of Internet addiction among junior high school students in Inner Mongolia and its associated factors, so as to provide a theoretical basis for the prevention and control of Internet addiction among junior high school students. Methods: In September 2023, 53 755 junior high school students were selected by stratified cluster random sampling method from all the flag counties in Inner Mongolia, and questionnaires were administered according to the "Monitoring and Intervention Program of Common Diseases and Health Influencing Factors of Students, by using the Internet Addiction Inventory and Generalized Anxiety Disorder Scale-7 Item. The Chi test and multiple Logistic regression analysis were used to explore related factors and draw nomograms. Results: The reported rate of Internet addiction among junior high school students in Inner Mongolia was 2.15%. The results of multivariate Logistic regression analyses showed that students were more likely to be in higher grades (grade eight: OR =1.54; grade nine: OR =1.64), being scolded by their parents ( OR =1.06), living in the school ( OR =2.28), being bullied in the school ( OR =1.91), anxiety symptoms ( OR =3.15), and substance abuse (smoking: OR =2.56; drinking alcohol: OR =2.29; inhaling soluble solvents for pleasure: OR =2.17; using cough suppressant except for coughing: OR =1.50; using sedatives without doctor s permission: OR =1.34) were positively correlated with Internet addiction among junior high school students in Inner Mongolia ( P <0.05). The area under the curve was 0.819, and the calibration curve showed that the predicted values were basically consistent with the measured values. Conclusions Internet addiction among junior high school students in Inner Mongolia is related to students living environment and substance abuse behavior. Attention should be paid to the living environment of junior high school students and strengthen the preventive education of substance abuse in order to reduce the occurrence of Internet addiction among junior high school students.

Background The safety of drinking water is closely related to people's health. In recent years, relevant studies have identified some health related problems with drinking water in Inner Mongolia Autonomous Region. The complex and diverse natural environment embraced by the vast jurisdiction of the region may lead to uneven drinking water quality across the region. Objective To evaluate eight chemicals including arsenic, cadmium, chromium (hexavalent), lead, mercury, fluoride, trichloromethane, and carbon tetrachloride in urban drinking water in Inner Mongolia Autonomous Region in 2021, and to provide reference for optimizing urban water supply system and ideas for further developing strategies to promote population health. Methods A total of 1228 monitoring sites were set up in urban areas of Inner Mongolia, and water samples were collected once in dry season (May) and once in wet season (August−September). Eight chemicals of interest in drinking water were detected according to the Standard examination methods for drinking water, and assessed for health risks using the health risk assessment model recommended by the United States Environmental Protection Agency (USEPA) and following the Technical guide for environmental health risk assessment of chemical exposure. Mann-Whitney U test was used to compare the concentrations of eight chemicals in urban drinking water by water seasons and water sample types. Results In 2021, a total of 2381 samples of urban drinking water were tested in the Inner Mongolia Autonomous Region, including 1195 samples in wet season and 1186 samples in dry season; 389 samples of finished water and 1992 samples of tap water. The positive rates of arsenic and fluoride were 26.25% and 96.77%, respectively. The positive rates of cadmium, chromium (hexavalent), lead, mercury, trichloromethane, and carbon tetrachloride were 6.22%, 16.63%, 6.09%, 16.67%, 18.98%, and 8.36%, respectively. The exceeding standard rate of fluoride was 4.87%. Trichloromethane and carbon tetrachloride were qualified in all samples. There were statistical differences in the concentrations of arsenic, cadmium, chromium (hexavalent), lead, and carbon tetrachloride in urban drinking water between water seasons (Z=−3.847, P<0.05; Z=2.464, P=0.014; Z=−3.129, P=0.002; Z=4.341, P<0.05; Z=4.342, P<0.05). Only fluoride concentration was found statistically different among different water sample types (Z=−2.287, P=0.022). The non-carcinogenic risks of ingestion and dermal exposure to each chemical in drinking water by water seasons and water sample types were all less than 1, but the P₉₅ total non-carcinogenic risks of oral exposure were greater than 1. The P₉₅ carcinogenic risks of oral exposure to some chemicals in drinking water by water seasons and water sample types were>10⁻⁴, which suggested carcinogenic risks, while the carcinogenic risks of dermal explore to chemicals were all less than 10⁻⁶. Conclusion In 2021, urban drinking water in Inner Mongolia Autonomous Region is generally safe, but arsenic, cadmium, chromium (hexavalent), lead, mercury, and fluoride still exceed the national limits, posing certain health risks.

0.05).Conclusion The 15 STR loci of Miao ethnic group show the characteristics of high polymorphism and hereditary stability.Therefore,the obtained data can be of applicable value in human population of Guangxi Miao genetics investigation,and forensic application,as well as individual identification and parent checkup.