Relationship between physical activity, screen-related sedentary behaviors and anxiety among adolescents in less developed areas of China.

This study aimed to explore the association between physical activity, screen-related sedentary behaviors, and anxiety. The current study used latent profile analysis (LPA) to identify homogenous subtypes of anxiety among adolescents in less-developed areas of China. Data were aggregated from 6 schools in the less-developed areas of China in September 2018. In total, 900 students were evaluated using the 100-item Mental Health Test (MHT) and Youth Risk Behavior Surveillance System (YRBSS) questionnaire. The LPA was conducted to explore the potential classification of anxiety, which makes full use of all the sample data and explore heterogeneous classifications within groups. Logistic regression was used for the multifactor analysis. A P value <.05 was considered statistically significant. The entropy value suggested that the model with 3 latent profile was the best choice. There were 223 adolescents in the severe anxiety group, accounting for 24.78%. Logistics regression analysis of anxiety revealed that the risk of severe anxiety in boys was lower (odds ratio [OR] = 0.317, P < .001) than in girls. Students had a significantly lower probability of suffering from severe anxiety in using cellphones or computers ≤ 2 hours/day than those used cellphones or computers＞2 hours/day (OR = 0.391, P = .004). Decreasing screen-related sedentary behaviors should be a target of community and school-based interventions, because high screen-related sedentary behaviors were associated with higher odds of anxiety among adolescents in less developed area of China.

Effect of empowerment educational program on AIDS prevention and treatment in one university / 中国学校卫生

Objective@#To apply and evaluate the effect of empowerment educational program on AIDS prevention and treatment among freshmen in one university.@*Methods@#The method of two stage stratified sampling was used to select the experimental and control group. The traditional health education was implemented among the control group, and the empowerment education was implemented for the experimental group. The effect of the two groups was compared before and after intervention.@*Results@#For experimental group, the awareness rate of AIDS(65.02%) ( χ 2=61.02， P <0.01) and the overall score of attitude and behavior(16.71± 2.53 )( t =-2.66， P <0.05) were significantly improved after intervention(82.96%，18.58±1.95). For the control group, there was significant difference in awareness rate of AIDS after intervention(67.70% vs 96.02%， χ 2=18.64, P <0.05), while there was no statistical difference in overall score of attitude and behavior after intervention(16.52±1.50 vs 17.16±1.57， t =-1.51, P =0.14). There was no significant difference in awareness rate between the two groups before intervention ( χ 2=0.36, P =0.55), but there was a statistical difference after intervention ( χ 2=20.42, P <0.01). There was statistical difference in attitude and behavior scores between the two groups after intervention ( P <0.05).@*Conclusion@#Empowerment educational program can improve the awareness rate of AIDS among college students, help to establish an objective attitude towards AIDS and infected patients, and to reduce high risk sexual behavior, also it is more effective compared to traditional education method.

Social and Structural Determinants of Health Inequities: Socioeconomic, Transportation-Related, and Provincial-Level Indicators of Cost-Related Forgone Hospital Care in China.

Despite near universal health insurance coverage in China, populations with low incomes may still face barriers in access and utilization of affordable health care. We aimed to identify the likelihood of forgone medical care due to cost by surveying individuals from the community to assess: (1) The percent with forgone medical care due to cost; and (2) Factors associated with forgone medical care due to cost. Surveys conducted (2016-2017) in Mandarin included demographic and medical care utilization-related items. Theoretically-informed, fully-adjusted analyses were employed. Approximately 94% of respondents had health insurance, which is somewhat similar to national estimates. Overall, 24% of respondents resided in rural areas, with 18% having less than a high school education, and 49% being male. More than 36% reported forgone medical care due to cost in the past 12 months. In fully-adjusted analyses, having lower education, generally not being satisfied with the commute to the hospital, and being a resident of a province with a lower density of physicians were associated with forgone medical care. Cost-related disparities in the access and utilization of needed medical care persist, even with near universal health insurance, which may be due to one's satisfaction with travel time to healthcare and other community assets.

Working Hours, Job Burnout, and Subjective Well-Being of Hospital Administrators: An Empirical Study Based on China's Tertiary Public Hospitals.

(1) Purpose: To analyze the role of job burnout in connection with working hours and subjective well-being (SWB) among hospital administrators in China's tertiary public hospitals. (2) Methods: A multi-stage, stratified, cluster random sampling method was used to select 443 hospital administrators in six tertiary public hospitals for study. The data were collected and analyzed using the working hours measuring scale, Maslach burnout, and the subjective well-being schedule. Pearson correlation, structural equation model, and bootstrap tests were conducted to examine the association between job burnout, working hours, and SWB. (3) Results: Among the 443 respondents, 330 worked more than 8 h per day on average (76.2%), 81 had the longest continuous working time more than 16 h (18.7%), and 362 worked overtime on weekends (82.2%). The prevalence of job burnout in hospital administrators was 62.8%, among which, 59.8% have mild burnout and 3.00% have severe burnout. In the dimension of emotional exhaustion, depersonalization, and reduced personal achievement, the proportion of people in high burnout was 21.0% (91/433), 15.0% (65/433), and 45.3% (196/433), respectively. Job burnout has a mediating effect between working hours and SWB, which accounted for 95.5% of the total effect. (4) Conclusion: Plagued by long working hours and severe job burnout, the hospital administrators in China's tertiary public hospitals may have low SWB. Working hours have a negative direct impact on job burnout and SWB, and an indirect impact on SWB through job burnout as a mediator. Targeted strategies should be taken to adjust working hours to promote the physical and mental health of hospital administrators.

Cumulative Exposure to Adverse Childhood Experience: Depressive Symptoms, Suicide Intensions and Suicide Plans among Senior High School Students in Nanchang City of China.

This study tested relationships between different types of adverse childhood experiences (ACE) and depressive symptoms, suicide intensions, suicide plans and examines the cumulative effects of adverse childhood experience on depressive, suicide intentions and suicide plans among senior high school students. We conducted a survey among five senior high schools in Nanchang city, which were selected through stratified random cluster sampling. Among the 884 respondents, 409 were male (46.27%), and 475 were female (53.73%); the age ranged from 14 to 18. During the past 12 months, 199 (22.51%) students presented to depressive symptoms, 125 (14.14%) students had suicide intensions, 55 (6.22%) students had suicide plans. As ACE scores increased, there was an increase in the odds of (1) depressive symptoms-one ACE (adjusted odds ratio, AOR = 2.096, p < 0.001), two ACEs (AOR = 3.155, p < 0.001) and three to five ACEs (AOR = 9.707, p < 0.001); suicide intensions-1 ACE (AOR = 1.831, p = 0.011), two ACEs (AOR = 2.632, p = 0.002) and three to five ACEs (AOR = 10.836, p < 0.001); and (2) suicide plans-one ACE (AOR = 2.599, p < 0.001), two ACEs (AOR = 4.748, p < 0.001) and three to five ACEs (AOR = 22.660, p < 0.001). We should increase the awareness of adolescents who have had adverse childhood experience, especially those with multiple ACEs to prevent depression and suicide among senior high school students.

A Latent Profile Analysis of Anxiety among Junior High School Students in Less Developed Rural Regions of China.

The purpose of this study is to understand the potential types of anxiety among middle school students by analyzing the current situation of middle school students' anxiety and its influencing factor. This study used a multistage stratified cluster random sampling to investigate students in grades 9 to 12. Mplus 7.4 was used for latent profile analysis. A total of 900 junior high school students were investigated. The junior high school students were divided into three subgroups by latent profile analysis. A total of 223 junior high school students experienced severe anxiety, accounting for 24.78%. Multivariate logistic regression analysis revealed that males are more likely to develop moderate and severe anxiety. The development of severe anxiety (OR = 0.562, p < 0.05) is less likely for students in schools with adequate mental health support. Students who were confident with their academic performances were less likely to develop moderate anxiety (OR = 0.377, p < 0.05). Students with extreme academic pressure are more likely to develop moderate anxiety (OR = 6.523, p < 0.05) and severe anxiety (OR = 11.579, p < 0.05). It is recommended that mental health counseling be set up in schools and to provide professional counselors to prevent serious anxiety for students. This paper also demonstrates a need to reduce students' academic pressure.

Research on the Relationships between Psychological Problems and School Bullying and Non-Suicidal Self-Injury among Rural Primary and Middle School Students in Developing Areas of China.

(1) Purpose: To analyze the role of psychological problems in connection with school bullying and non-suicidal self-injury (NSSI) among rural primary and middle school students in developing areas of China. (2) Methods: A multi-stage, stratified, cluster random sampling method was used to select 2284 rural primary and middle school students in Jiangxi Province for study. Questionnaires regarding the health risk behaviors of children in developing areas were left behind at primary and middle schools, and they were later collected and analyzed by using the mental health diagnostic monitoring scale for Chinese primary and middle school students. Pearson correlation, logistic regression, and bootstrap tests were conducted to analyze the association between psychological problems, school bullying, and NSSI. (3) Results: The incidence of NSSI in rural primary and middle school students in Jiangxi Province was 14.84%. Compared with other children with behavioral problems, those who had experienced school bullying and had mild/severe psychological problems were more likely to have engaged in NSSI behaviors (p < 0.001). Psychological problems have a mediating effect between school bullying and NSSI, which accounted for 12.96% of the total effect. (4) Conclusion: Psychological problems are likely an effect modifier in the connection between school bullying and NSSI behaviors. Therefore, effectively targeting psychological problems in rural primary and middle school students in Jiangxi Province may help prevent and control NSSI behaviors in students who have experienced school bullying.

Study on the Utilization of Inpatient Services for Middle-Aged and Elderly Rural Females in Less Developed Regions of China.

The aim of this study is to understand the utilization of inpatient services and its contributing factors among middle-aged and elderly females (MAEF) in less developed rural regions. Five surveys were conducted between 2006 and 2014 with rural residents of Jiangxi by stratified cluster random sampling. Participant females included only those who were aged 45 and above. Complex sampling logistics analysis was performed to analyze the effect of three factors on inpatient service. Complex sampling logistics regression analysis revealed that the probability of hospitalization for the divorced or widowed females was significantly lower than that of married ones (aOR = 0.177, p < 0.05). However, the probability of early discharge was significantly higher among divorced or widowed females than married ones (aOR = 3.237, p < 0.05). In addition, females with chronic diseases were more likely to be hospitalized (aOR = 3.682, p < 0.05). Also, early discharge (aOR = 7.689, p < 0.05) occurred among the participants who should be hospitalized but were not hospitalized occurred (aOR = 3.258, p < 0.05). The continuous improvement of the new rural cooperative medical policy has promoted the utilization of inpatient services for the MAEF. Findings from this study emphasize the need to strengthen the prevention and treatment of chronic diseases among middle-aged and elderly women.

An Observational Assessment of Park-based Physical Activity in Older Adults in Nanchang, China.

Objectives: Parks are more widely used by older adults in East Asia than in the United States. Parks are an important community asset for healthy aging; yet, little is known about park usage and features among older adults in China. Methods: The Community Park Audit Tool and the System for Observing Play and Recreation (SOPARC) were used to assess park features, PA levels and primary activities among 40,469 older adults in Nanchang, China. Results: None of the 8 parks observed had basketball courts or baseball fields and only one had a playground. Results indicated that about half of older adults were active in parks, with women, cooler temperatures, weekdays, and morning hours being related to higher levels of activity. Conclusions: Lessons from the construction of parks in China may be useful in increasing park use in older adults in western countries. Features such as exercise equipment, water features, and small exercise areas were common where western parks are often designed with features for teens and youth including basketball courts, baseball fields, and playgrounds.

Comparative Study of Two Methods of Enteric Virus Detection and Enteric Virus Relationship with Bacterial Indicator in Poyang Lake, Jiangxi, China.

Currently, water contaminated with fecal matter poses a threat to public health and safety. Thus, enteric viruses are tested for as a part of water quality indicator assays; however, enteric viruses have not yet been listed in the criteria. Effective and sensitive methods for detecting enteric viruses are required in order to increase water safety. This study utilized enteric viruses as possible alternative indicators of water quality to examine fresh water in six sites in Poyang Lake, Nanchang, Jiangxi Province. The presence of norovirus geno-groups II (NoV GII), enteroviruses (EoV) and adenoviruses (AdV) were determined using Tianjin's protocol and Hawaii's protocol during a six month period from 2016-2017. The former used an electropositive material method for viral concentration and Taqman-q reverse transcription polymerase chain reaction (RT-PCR) to detect enteric viruses; while the latter used a filtration-based method for viral concentration and RT-PCR for enteric virus detection. There is a statistically significant difference between Tianjin's method and Hawaii's method for the detection of enteric viruses, such as NoV GII, EoV, and AdV (n = 36, p < 0.001). The enteric viruses showed no significant positive correlation with bacteria indicators (n = 36, p > 0.05). These data stress the need for additional indicators when establishing water quality systems, and the possibility of using enteric viruses as water quality indicators. It has become essential to improve shortcomings in order to search for an adequate method to detect enteric viruses in water and to implement such method in water quality monitoring.

Hospitalization Services Utilization Between Permanent and Migrant Females in Underdeveloped Rural Regions and Contributing Factors-A Five-Time Data Collection and Analysis.

The proportion of migrating females has increased, and more often, old females are left in rural regions. Resources are needed to provide suitable hospitalization service to females in underdeveloped rural regions. Using multi-stage hierarchical cluster random sampling method, nine towns from three counties were enrolled in five-time points between 2006 and 2014 in this study. The research subjects of this study were females age 15 and up. Data regarding the utilization of inpatient services were collected and analyzed. Complex sampling logistic regression was conducted to analyze influencing factors. This study reveals that for both permanent females and migrant females, the older their age, the higher their hospitalization rate. The utilization of hospitalization service for permanent females was associated with the occurrence of chronic diseases (adjusted Odds Ratio (aOR) = 5.402). In addition, permanent females suffering from chronic diseases were more likely to avoid hospitalization despite their doctor's advice (aOR = 34.657) or leave the hospital early against medical advice (AMA) (aOR = 10.009). Interventions to combat chronic diseases and adjust compensation schemes for permanent females need to be provided.

Research on Relationships between Sexual Identity, Adverse Childhood Experiences and Non-Suicidal Self-Injury among Rural High School Students in Less Developed Areas of China.

Purpose: The objective of this study was to examine the influence of sexual identity and adverse childhood experiences (ACEs) on non-suicidal self-injury (NSSI) among rural high school students in less developed areas of China. Methods: Behavior risk factors data collected from 1810 students from a high school in Jiangxi province, China. Five measures of childhood abuse and household dysfunction were summarized, and ACE was divided into 0, 1, 2, 3-5 ACEs. Logistic regression analysis was used to explore the influence of sexual identity, adverse childhood experiences, and their interaction with non-suicidal self-injury. Results: Compared with heterosexual students, high school students who identify as lesbian, gay, or bisexual (LGB) have a higher tendency of non-suicidal self-injury (AOR = 3.250, 95% CI = 1.69-6.28, p < 0.01). There was also a graded relationship between cumulative ACEs exposure and non-suicidal self-injury behaviors (AOR = 1.627, 95% CI = 1.02-2.60, p < 0.05). Odds for NSSI are higher among students with both experienced ACEs and identified as LGB (AOR = 2.821, 95% CI = 1.51-5.29, p < 0.05). Conclusions: Non-suicidal self-injury is associated with ACEs exposure and with those who identify as LGB, and the NSSI odds are greater when students identify as LGB and have experienced ACEs. More interventions to reduce non-suicidal self-injury should focus on LGB and ACEs and more attention needs to be paid to those who identify as LGB and have been exposed to ACEs.

Social Capital Associated with Quality of Life among People Living with HIV/AIDS in Nanchang, China.

Background: This study aims to explore the relationship between quality of life (QOL) and social capital factors among "people living with HIV/AIDS" (PLWHA), in order to improve their quality of life and help them to release AIDS discrimination. Methods: A cross-sectional survey with 225 PLWHA was done in Nanchang, China, between January and June of 2015. Questionnaires consisted of a socio-demographic questionnaire, Personal Social Capital Scale and Medical Outcomes Study HIV Health Survey. To identify social capital factors influencing QOL among PLWHA, t-test and multiple linear regression were used as statistical tools. The analysis of data was conducted using SPSS 22.0 with a significant value of p < 0.05. Results: The scores of total social capital, bonding social capital and bridging social capital were 23.68 ± 5.55, 14.11 ± 3.40 and 9.46 ± 3.43 respectively. The scores of Physical Health Summary (PHS) and Mental Health Summary (MHS) were 51.88 ± 7.04 and 49.29 ± 6.60. Multiple linear regression analysis showed that age (B = -0.137, p = 0.020), income (B = 0.2170, p ≤ 0.001), employment (B = 0.112, p = 0.043) and bonding social capital (B = 0.178, p = 0.001) had significant effects on PHS. Bonding social capital was the most important influencing factor for MHS (B = 0.506, p < 0.001). There was no significant relationship between bridging social capital and QOL (p > 0.05). Conclusions: The PLWHA community has low social capital and a poor QOL in Nanchang. Bonding social capital had a positive impact on the QOL of PLWHA. There is an urgent need to build a better social support system based on bonding social capital for PLWHA. It is worth further exploring to identify how to make full use of bridging social capital for improving QOL among PLWHA.

An investigation on health risk behaviors among high school students in Jiangxi province / 中国学校卫生

Objective@#To determine health risk behaviors related to accidental injury of adolescent in Jiangxi province,and to provide a peference for taking targeted measures to prevent the occurence of adolescent’s risk behaviors. @*Methods@#By using the cluster stratified sampling, students of grade one and grade two from 10 classes in 5 middle schools in Nanchang city and from 1 middle school in Wuyuan county were selected. Health risk behaviors were investigated through questionnaire survey and were compared within the two areas.@*Results@#Regarding to safety, the rates of never or rarely wearing a helmet when riding a bicycle during the past 12 months, never or rarely wearing a seat belt, text or Email while driving a vehicle and in a physical fight were very high. In Wuyuan county, 35.2% of the students have ever tried cigarette smoking, 51.5% of the students have had at least one drink of alcohol, 4.0% of the students have ever had sexual intercourse, 32.7% of the students describe their weight as slightly or very overweight, 49.1% of the students trying to lose weight. After standardized, the rate of health risk behaviors in Nanchang city was higher than that in Wuyuan county.@*Conclusion@#here are more healthrisk behaviors found among middle school students in Nanchang than in Wuyuan county.The targeted measures should be taken to develop healthy behavior habits of the students to effectively reduce its occurence.

Daily behavior and self-perceived academic performance among students in Jiangxi Province / 中国学校卫生

Objective@#To analyze the relationship between daily behavior and self-perceived academic performance among students in Jiangxi, and to provide a scientific basis for developing health behavior among adolescents and children.@*Methods@#By using stratified cluster sampling, 12 primary and secondary schools from six counties of Jiangxi Province were selected, and a total of 2 284 students were investigated with questions including breakfast consumption, number of days participating in sports activities (≥45 min) and the average screen time during the past 7 days. Regression analysis was carried out by using ordered multi-classification logistic.@*Results@#Of the 2 284 students surveyed, 1 374(60.16%) perceived their academic performance as very good or good, 613 (26.84%) and 297(13.00%) perceived as moderate or poor. Primary school, having breakfast every day, not playing on mobile or computer during weekday was positively associated with higher self-perceived academic performance (OR=0.50, 0.57 and 0.64, respectively, P<0.05), no sports activities ≥45 min during the past 7 d was associated with poor(OR=1.57, P<0.01). Among the 2 284 students, 67.43% students ate breakfast every day in the past 7 d, 75.39% students did not play mobile phones or computers at school, 40.89% students did not participate in sports activities (≥45 min).@*Conclusion@#Breakfast skipping and insufficient physical exercise shows adverse effects, and no/limited screen time during weekdays shows positive effects on academic performance. Intervention of visky behaviors should to carried out from different perspectives to promote the develpment of the health habits among students.

Investigation on Task Shifting of HIV/AIDS Follow-Up Management Workers in New Launched Areas, China.

Background: This study aimed to understand attitudes of HIV/AIDS follow-up workers regarding task shifting, reveal the current conditions of this implementation, as well as to find out any challenges of early-stage implementation. Methods: Taking Jiangxi Province as an example, a cross-sectional survey with 102 health professionals in CDCs (Centers for Disease Control and Prevention) and 92 health care providers in primary health institutions was conducted from November 2016 to January 2017. This survey includes the demographic backgrounds of participants, their attitudes towards task shifting, and the main difficulties faced in their work, etc. Results: 60.8% of professionals and 77.2% of providers hold positive attitudes towards task shifting. Both health professionals and providers express their concerns about unclear and undefined funds distribution and lack of confidentiality of PLWHA (people living with HIV) in local primary health institutions. Conclusions: The majority of health workers hold positive attitudes towards task shifting. It also highlights some negative reactions in implementation, and reveals the main difficulties that constitute barriers to follow-up. Findings from this study may provide evidence for enhancing future implementation of task shifting.

Impact of the New Cooperative Medical Scheme on the Rural Residents' Hospitalization Medical Expenses: A Five-Year Survey Study for the Jiangxi Province in China.

This survey study was conducted to understand the effect of the New Cooperative Medical Scheme (NCMS) on farmers’ medical expenses through comparing the information from five investigations and to obtain a scientific basis for a more applicable NCMS. The survey was carried out through interviewing farmers in their homes. The multi-phase stratified cluster random sampling was adopted to select 3 counties from all 92 counties of the Jiangxi province, 9 townships from the 3 selected counties, 27 villages from the selected 9 townships, and 60 families from each village between 2006 and 2014, and a longitudinal comparative analysis was conducted. The numbers of households/overall sample for the five years were 1924/8082, 1879/8015, 1885/7506, 1890/7857, and 1896/7811, respectively. We collected family members’ social demographic characteristics, health resources, and peoples’ health and medical expenses and reimbursement of each family member. The adjusted hospitalization expenses per capita of township hospitals and county hospitals were totally on a rising trend. However, the costs of tertiary hospitals were on a decreasing tendency. In addition, the expenses for county hospitalization per admission were on an upward trend in general. Furthermore, the total hospitalization expenses and reimbursement per capita (the insurance paid out for the hospitalization expenses) were also all on an upward trend. The proportion of reimbursement also had a tendency of increasing from 24.41% in 2006 to 41.34% in 2014. The costs paid from farmers’ pockets were fluctuated, but in general all lower than the costs in 2006. Furthermore, the percentage of hospitalization expenses from farmers’ annual incomes gradually decreased each year from 56.38% in 2006 to 26.58% in 2014. NCMS program has had an obvious impact on the hospitalization expenses in the Jiangxi rural area. It reduced the hospitalization expenses of the tertiary hospitals significantly. In addition, the program has also encouraged farmers to get more health care. However, there are still some shortages associated with present construction of the NCMS. Hence, there is a need for local government to continue to take effective countermeasures to control the rising trend of hospitalization expense.

Monitoring of Poyang lake water for sewage contamination using human enteric viruses as an indicator.

BACKGROUND: Recreational water contaminated with fecal pollution poses a great public health concern, as fecal waste may cause serious waterborne illnesses. Current recreational water standards using fecal indicator bacteria (FIB) have their limitations for human protection especially in developing countries such as China. METHODS: To explore the potential use of enteric viruses as a potential indicator of fecal contamination, four viruses: norovirus geno-groups I and II, enteroviruses, and adenoviruses were tested in this study using molecular detection methods and sensitive RT-PC developed in the University of Hawaii. Water samples were also tested for FIB in order to determine their association with enteric virus detection. RESULTS: All sample sites tested positive for four enteric viruses. Human enterovirus (58%) and adenovirus (67%) were more frequently detected from these six sites, followed by norovirus I (50%) and norovirus II (38%). Six sampling sites all met the level-I water quality of GB3838-2002 criteria in microbiological level, but they all tested positive for enteric viruses. CONCLUSION: These findings indicate the current sewage contamination of Poyang Lake and also support the essential need of additional indicator such as human enteric viruses for enhanced monitoring of water quality since the presence of enteric viruses does not always correlate with fecal bacterial indicator detection.

Physical activity and park use of youth in Nanchang, China.

Physical inactivity is a growing issue in Chinese youth, but parks can facilitate traditional and non-traditional forms of physical activity for little to no cost. Despite this opportunity, very little is known regarding park use among Chinese youth. The purpose of this study was to conduct a cross-sectional observational study of park usage and physical activity of youth in municipal parks in Nanchang, China. Data were collected in June of 2014 in eight parks across Nanchang, Jiangxi a large city in southeast China. Physical activity was measured by a modified version of System for Observing Play and Recreation in Communities. Ordered hierarchic generalized linear models were estimated using a logit link function. The influence of the park was estimated using random effects, with fixed effects and park, environmental, and park user characteristics. Youth were most often seen active in the afternoon, on weekends, and during cooler times (≤ 29 °C). Paradoxically, more children were active when air quality was poorer. Older boys were more active than younger boys, but no differences were observed in girls. More children were seen active in unstructured play compared to structured activities. The results suggest parks are an important setting for physical activity among Chinese youth, and that unstructured activities can play an important role in promoting greater youth physical activity.

Development of a novel and highly efficient method of isolating bacteriophages from water.

Bacteriophages are widely used to the treatment of drug-resistant bacteria and the improvement of food safety through bacterial lysis. However, the limited investigations on bacteriophage restrict their further application. In this study, a novel and highly efficient method was developed for isolating bacteriophage from water based on the electropositive silica gel particles (ESPs) method. To optimize the ESPs method, we evaluated the eluent type, flow rate, pH, temperature, and inoculation concentration of bacteriophage using bacteriophage f2. The quantitative detection reported that the recovery of the ESPs method reached over 90%. The qualitative detection demonstrated that the ESPs method effectively isolated 70% of extremely low-concentration bacteriophage (100 PFU/100L). Based on the host bacteria composed of 33 standard strains and 10 isolated strains, the bacteriophages in 18 water samples collected from the three sites in the Tianjin Haihe River Basin were isolated by the ESPs and traditional methods. Results showed that the ESPs method was significantly superior to the traditional method. The ESPs method isolated 32 strains of bacteriophage, whereas the traditional method isolated 15 strains. The sample isolation efficiency and bacteriophage isolation efficiency of the ESPs method were 3.28 and 2.13 times higher than those of the traditional method. The developed ESPs method was characterized by high isolation efficiency, efficient handling of large water sample size and low requirement on water quality.