Study of Aerobics Effects on Female College Students＇ Health

Aerobics includes gymnastics, music, dance and aesthetics, using specialized equipment by hand and holding light equipment to achieve fitness and operation of exercises, it is a bodybuilding methods centering for the purpose of emerging entertainment and ornamental sports, and it is also a strong public artistic gymnastics. It is with superb skill, charming and colorful parade of action, posture which is coordinated with the music to demonstrate the extraordinary artistic charm, thus attracting more and more students to participate in. Because it is different from traditional hand gymnastic exercises, and does not have too high demands for space and equipment. Practicing it just needs fast-paced and lively musical accompaniment, and dynamic movements can make people feel good, so it wins the majority of young people, especially girls. Calisthenics is as one of the means to work out for students; in particular, it develops a lifelong habit of physical exercise and plays an important role for college girls＇ lifelong fitness awareness. The topic is studying female college students on aerobics body shape, function, quality and impact of mental health to promote the development of physical education reform.

The influence that aerobics have on mental health of college students

Aerobics become an indispensable item in college physical education class. The article will talk about the influence of aerobics on mental health of college students aiming at the fact that mass aerobics haven＇ t developed very well. Aerobics expand the traditional pattern of school physical education, in addition to improve and animate sports classroom atmosphere; students can be fully met the physical and mental demand, so as students can be guided to actively participate in physical exercise, making further promotion of students＇ body and function development; students＇ physical fitness involving coordination, softness, power and endurance can also be fully developed. Students can develop good body posture, shape their physical beauty and performance of actions, cultivate sentiments and further demonstrate the beauty and health of themselves.

Soil concentrations and soil-air exchange of organochlorine pesticides along the Aba profile, east of the Tibetan Plateau, western China

Mianzhu--Aba profile, east of the Tibetan Plateau, was selected to study the occurrence of organo- chlorine pesticides （OCPs） along an altitudinal gradient. Dichlorodiphenyltrichloroethanes （DDTs）, hexachlorocy- clohexanes （HCHs） and Aldrin, Dieldrin and Endrin （Drins） in surface soils were detected in winter （March） and summer （July）. Soil concentrations （ng.g-1, dw） in winter and summer ranged as follws： DDTs, 0.37-179.16 and 0.32-42.57; HCHs, 0.14-10.76 and 0.55-32.71; Drins, N.D-3.99 and 0.02-6.93, respectively. Main soil OCPs were p,p＇-DDT, p,p＇-DDE, fl-HCH and Drins, among which Drins were rarely reported in current literature of the Tibetan Plateau. Higher OCP concentra- tions in the profile were attributed close to the agricultural fields of the Sichuan Basin, current lindane and non- dicofol DDTs inputs, and also long-range atmospheric transport from abroad. Soil OCP concentrations underwent obvious seasonal variation, with higher DDTs in winter and higher HCHs and Drins in summer. It may be caused by climatic conditions, summer monsoon type, and physico-chemical properties of such contaminants. Though ＂rest＂ phenomenon occurred in some sampling sites, HCHs and Drins showed an increasing trend with increasing altitude, while DDTs showed an evident decrease with increasing altitude. The altitudinal distribu- tions of OCPs were all consistent with previous findings in other mountainous regions. A primary fugacity analysis on OCPs soil-air exchange indicated that the profile may be secondary sources for HCHs and Endrin. As with Aldrin,Dieldrin, and DDTs, the profile may be both secondary sources and sinks.

Fate of PM2.5-bound PAHs in Xiangyang, central China during 2018 Chinese spring festival: Influence of fireworks burning and air-mass transport

Variations of levels,possible source and air mass transmission were investigated for 16 USEPA priority-controlled PAHs in PM2.5 during 2018 Chinese Spring Festival(CSF)in Xiangyang City,central China which is the North-South pollutant airmass transport channel of China.Totally 37 samples were collected.Mass concentrations of 16 PAHs for the Pre–CSF day(Pre–CSFD),during the CSF day(CSFD)and after the CSF day(Af–CSFD)are 33.78±17.68 ng/m3,22.98±6.49 ng/m3,and 8.99±4.44 ng/m3,respectively.High resolution samples showed that 16 PAHs are higher in the morning(06:00–11:00)or afternoon(11:30–16:30),than those in the evening(17:00–22:00)and at night(22:30–05:30),whereas the result is reversed during the CSFD.Fireworks burning can obviously increase the mass concentration of PAHs.Air mass trajectory indicated that Xiangyang is a sink area of pollutants for northwest and southeast,and the sources of the northeast and southwest.The air mass only can be transmitted out through northeast and southwest.It is effective for improvement of air quality in Wuhan and Hunan to control fireworks emission in Henan and local areas.Fireworks burning was an important source for PAHs during CSFD,biomass,coal combustion,and traffic emission were the main sources of PAHs for Pre–CSFD and Af–CSFD periods.The health risk on the CSFD was higher than the acceptable levels,especially during the intensive fireworks burning,the risk value far exceed 1.0×10^-4,controlling burning fireworks is required.

Organochlorine pesticide residues in surface water from Sichuan Basin to Aba Prefecture profile, east of the Tibetan Plateau

Organochlorine pesticides （OCPs） found in rivers from the Sichuan Basin to Aba Prefectttre profile were analyzed to assess possible health risks to adults and children who use the river as a source of drinking water. OCP concentrations in surface water ranged between 22.29-274.28 ng·L^-1. Compared with other published data around the world, OCP levels in this study were moderate. Among all OCPs, hexachlorobenzene （HCB） and hexa- chlorocyclohexanes （HCHs） were the predominant com- pounds. Higher concentrations of OCPs were attributed close to the agricultural fields of the Sichuan Basin, current OCPs inputs, and long-range atmospheric transport from abroad. Various spatial patterns of OCPs in the profile might be affected by the usage and physicochemical properties of the pesticides, in addition to the adjacent geographical environment. The health risk assessment indicated that most OCPs had little impact on human health according to the acceptable risk level for carcino- gens （10^-6） recommended by the US EPA. However, carcinogenic effects caused by heptachlor, Aldrin, HCB, and a-HCH might occur in drinking water. The risk of negative impacts caused by OCPs is much higher for children than for adults.

Background levels of OCPs,PCBs,and PAHs in soils from the eastern Pamirs,China,an alpine region influenced by westerly atmospheric transport

Long-range atmospheric transport(LRAT)plays a crucial role in the occurrence of persis-tent organic pollutants(POPs)in remote regions.When studying the LRAT of POPs on the Tibetan Plateau,westerly-controlled regions have received insufficient attention compared with regions influenced by the Indian monsoon or air flow from East Asia.We investigated the residual levels of POPs in soils from the eastern Pamirs and used air backward trajectory analysis to elucidate the influence of potential source regions via LRAT.Organochlorine pes-ticides(OCPs,mainly comprising DDTs,HCHs,and HCB),polychlorinated biphenyls(PCBs,mainly comprising penta-and hexa-CBs),and polycyclic aromatic hydrocarbons(PAHs,mainly comprising three-and four-ring)were detected at low concentrations of 40-1000,<MDL-88,and 2100-34,000 pg/g,respectively.We elucidated three major geographical dis-tribution patterns of POPs,which were influenced by(1)the distribution of total organic carbon and black carbon in soil,(2)historical use of pesticides in the Tarim Basin,and(3)continuous emissions.Central Asia and the Tarim Basin were major potential source regions of POPs reaching the eastern Pamirs via LRAT.Historical use of technical HCH or lindane and technical DDT in potential source regions may contribute to the accumulation of HCHs and DDTs in the eastern Pamirs,respectively.Local sources seem to play a more important role in the occurrence of PAHs in the study area.By being under the control of less contaminated westerly air flow,the eastern Pamirs are more pristine than the core of the Tibetan Plateau where the Indian and East Asia monsoons deliver contaminants from highly industrialized areas in East China and India.

Concentrations and classification of HCHs and DDTs in soil from the lower reaches of the Jiulong River, China

Soil is an important source to other environ- mental media and organisms for organochlorine pesticides （OCPs） bioaccumulation. Twenty-four representative sur- face soil samples were collected from the lower reaches of the Jiulong River, China, in 2009. The concentrations of hexachlorocyclohexane isomers （HCHs） ranged from 0.38 to 39.52 ng.g~, with a mean value of 9.51 ng.g-~. The concentrations of dichlorodiphenyltrichloroethanes （DDTs） and their metabolites were within the ranges of 0.94-700.99 ng. gl, with a mean value of 71.17 ng. g-1. The concentrations of HCHs and DDTs in the soil were lower than the first grade level （50 ng. g-a） of the Chinese Environmental Quality Standard （GB 15618-1995）. Hier- archical Cluster Analysis （HCA） and Pearson＇s bivariate Correlations Analysis （PCA） were used to analyse the distribution and contamination levels of OCPs in this region. The results showed that DDTs were the major contaminants and there were no significant correlations between various OCPs concentrations and the total organic carbon （TOC） contents. A significant positive correlation was observed between HCHs and DDTs （p 〈 0.01）, which indicates that HCHs and DDTs may have similar sources and fate in the study area.

Chinese Fetal Growth:A Multicenter Cohort Study Based on Fetal Ultrasound Measurements

Objective:To build a reference fetal growth chart for the Chinese population based on fetal ultrasound measurements.Methods:This was a multicenter,population-based retrospective cohort study.Longitudinal ultrasound measurement data were collected from 24 hospitals in 18 provinces of China from 1st September through 31st October of 2019.The estimated fetal weight(EFW)was calculated based on head circumference,abdominal circumference,and femur length using Hadlock formula 3.Fetal growth curves were estimated using a two-level linear regression model with cubic splines.All participants were divided into two groups:the northern group(n=5829)and the southern group(n=3246)based on the geographical division of China and male fetus group(n=4775)and female fetus group(n=4300)based on fetal gender.The EFW was compared by fetal gender and geographical group.All statistical models were adjusted for maternal sociodemographic characteristics.Results:A total of 9075 participants with 31,700 ultrasound measurement records were included in this study.Male fetuses demonstrated significantly larger EFW compared to female ones starting at 16 weeks of gestation and extending to delivery(global testP<0.01).The overall geographic difference in EFW was significant(global testP=0.03),and week-specific comparisons showed that the northern group had a greater EFW starting at 15 weeks of gestation and extending to 29 weeks of gestation,although this difference did not extend to the time of delivery.TheZ-score of EFW confirmed that our Chinese fetal growth charts differed from previously published standards.Conclusion:This study provides EFW and ultrasound biometric reference measurements for Chinese fetuses and reveals differences from other fetal growth charts.The chart is worth promoting in more regions of China but should be tested prudently before use.