Decreasing Production and Potential Urban Explosion of Nighttime Nitrate Radicals amid Emission Reduction Efforts.

Nighttime oxidation by nitrate (NO3) radicals has important ramifications on nocturnal aerosol formation and hence the climate and human health. Nitrate radicals are produced by the reaction of NO2 and O3. Despite large decreases in anthropogenic emissions of nitrogen oxides (NOx = NO + NO2), a previous study found significant increases in NO3 production (PNO3) from 2014 to 2019 in China, in contrast to decreasing trends in the U.S. and Europe. Using the summer observations from 2014 to 2022, we analyze the interannual variability of nocturnal PNO3 using a systematic framework, in which PNO3 is diagnosed as a function of odd oxygen (Ox = O3 + NO2) and the NO2/O3 ratio. We did not find an increase of PNO3 from 2014 to 2022 in China due to a continuous decrease in the NO2/O3 ratio, although PNO3 is modulated by the variation in Ox. Using in situ observations obtained in Beijing in 2007, we demonstrate the potential for an upsurge resembling an "explosion" in urban nighttime NO3 radicals amid emission reduction efforts.

Awareness of monkeypox prevention knowledge among inbound personnel / 预防医学

Objective@# To investigate the awareness of monkeypox prevention knowledge and its influencing factors among inbound personnel, so as to provide insights into intensified health education for monkeypox prevention and control.@*Methods@#Inbound personnel at ages of 16 years and older were sampled using a convenient sampling method from centralized medical isolation observation points in Gongshu District, Hangzhou City in November and December 2022. Participants' demographic features, history of travel in countries where monkeypox cases were reported and awareness of monkeypox prevention knowledge were collected through questionnaire surveys, and factors affecting the awareness of monkeypox prevention knowledge were identified using a multivariable logistic regression model. @*Results@#A total of 306 questionnaires were allocated, and 293 valid questionnaires were recovered, with an effective response rate of 95.75%. The respondents included 192 men (65.53%) and 101 women (34.47%), and hand a median (interquartile range) age of 36 (16) years. The overall awareness of monkeypox prevention knowledge was 44.71%, and the awareness rates of preventive measures, source of infection, transmission route, susceptible populations and clinical manifestations were 82.94%, 79.18%, 75.09%, 60.75% and 60.07%, respectively. Multivariable logistic regression analysis showed that workers (OR=0.179, 95%CI: 0.040-0.800), self-employed individuals (OR=0.090, 95%CI: 0.018-0.451), and those with other occupations (OR=0.157, 95%CI: 0.034-0.728) had lower awareness of monkeypox prevention knowledge than students, and individuals who had never heard of monkeypox (OR=0.056, 95%CI: 0.007-0.447) had lower awareness of monkeypox prevention knowledge than those who had heard of it. In addition, individuals who were not concerned about monkeypox epidemics (OR=0.048, 95%CI: 0.004-0.563) had lower awareness than those who were very concerned. @*Conclusions@#Inbound personnel have low awareness of monkeypox prevention knowledge, and occupation, having heard of monkeypox and concern about monkeypox epidemics may affect the awareness of monkeypox prevention knowledge. Intensified health education about monkeypox is required to improve the preventive awareness among inbound personnel.

Pedestrian traffic safety behaviors among primary and secondary school students in Xiacheng District / 预防医学

Objective@#To investigate the pedestrian traffic safety behaviors of primary and secondary school students in Xiacheng District of Hangzhou,and to provide reference for formulating traffic safety strategy. @*Methods@# In October 2015,nine campuses of six schools in Xiacheng District were selected to observe the pedestrian traffic safety behaviors of the primary and secondary school students walking to and from school,such as taking the zebra crossing,observing the traffic condition,running and playing with cellphones when walking across the road.@*Results@#Totally 2 585 students were investigated,and 2 580 students were valid（99.81%）. When walking across the road,1 887 people took the zebra crossing,accounting for 73.14%;71.89% of boys and 74.51% of girls took the zebra crossing,and there was no significant difference（P>0.05）;64.76% and 81.32% of the students took the zebra crossing on the way to school and home,with a significant difference（P<0.05）. When walking across the road,1 683 students people observed the traffic conditions,accounting for 65.23%;63.61% of boys and 67.02% of girls observed the traffic conditions,and there was no significant difference（P>0.05）;64.05% and 66.39% of the students observed the traffic conditions on the way to school and home,with a significant difference（P<0.05）.There were 362 students running across the road, accounting for 14.03%;15.31% of boys and 12.62% of girls ran across the road,and there was no significant difference（P>0.05）;9.26% and 18.68% of the students ran across the road on the way to school and home,with a significant difference（P<0.05）. There were 53 students playing with cellphones when crossing the road,accounting for 2.05%;2.29% of boys and 1.79% of girls played with cellphones,and there was no significant difference（P>0.05）;1.41% and 2.68% of the students played with cellphones on the way to school and home,with a significant difference（P<0.05）. @*Conclusions @#Primary and secondary school students have dangerous behaviors when walking across the road. We should focus on the intervention of not taking the zebra crossing and not observing traffic conditions when crossing the road on the way to school,and playing with cellphones on the way home.

Prevalence of condomless anal intercourse and recent HIV testing and their associated factors among men who have sex with men in Hangzhou, China: A respondent-driven sampling survey.

Men who have sex with men (MSM) are a large high-risk population for HIV infection in recent years in China. A cross-sectional survey was conducted in Hangzhou, China, to determine rates of condomless anal intercourse (CAI), recent HIV testing (in the recent year) and associated factors using respondent-driven sampling. Questionnaires using face-to-face interviews were employed to collect data on sexual risk behaviors and HIV testing. Five hundred eleven MSM were recruited, of which 459 (89.8%) had anal intercourse in the past 6 months. Of these 459 participants, 457 (99.6%) answered whether they had taken an HIV test in the recent year, so only their data were analyzed. Weighted data were analyzed using bivariate and multivariate logistic regression analysis. The CAI rate with male partners in the past 6 months was 43.7% (95% confidence interval [CI], 34.0-51.5%), while the rate of condomless vaginal intercourse (CVI) was 21.6% (95% CI, 15.6-32.3%). The prevalence of recent HIV testing was 56.8% (95% CI, 48.7-66.5%), while the prevalence of HIV and syphilis were 8.8% and 6.5%, respectively. Multivariate analysis indicated that CAI was associated with earlier homosexual debut, suicidal inclinations, childhood sexual abuse, HIV testing in the recent year, and lower estimate of HIV prevalence. Recent HIV testing was associated with homosexual debut age, engaging in CAI with male partners in the past 6 months, having oral sex in the past 6 months, self-perceived higher likelihood of HIV infection, knowing about antiretroviral therapy for HIV/AIDS, receiving AIDS/sexually transmitted infection (STI) interventions in the past year, and syphilis infection. Given high prevalence of HIV and syphilis, high levels of CAI and CVI, and low HIV testing rate, the results indicated high risk of HIV infection and transmission among MSM. HIV prevention interventions should target MSM with early homosexual debut and psychosocial health problems, while HIV/AIDS education among MSM should focus on increasing knowledge of HIV risk, estimated HIV prevalence and antiretroviral therapy, and improving risk perception of HIV acquisition.

[Status of using condoms and its influencing factors of female commercial sex workers in small service places in Hangzhou City].

OBJECTIVE: To understand the status of using condoms and its influencing factors of female commercial sex workers in small service places, providing the basis for AIDS behavior interference. METHODS: All female commercial sex workers from 100 small service places in Hangzhou Xiacheng District were surveyed by behavior surveillance questionnaire of AIDS. The status of using condoms was known when took place commercial sex. The relationship among total 13 factors about age, practice time, marriage, education, AIDS knowledge score, etc and every commercial sex by using condoms, was analyzed with univariate analysis and Multivariate Logistic regression. RESULTS: Average age of 326 female commercial sex workers were (24.89 +/- 5.55) years old, less than 1 year practice time workers accounted for 47.85%, less than middle school accounted for 84.36%. The rates of using condoms in one recent commercial sex and every commercial sex in last month were 85.28% and 53.68%. Multivariate Logistic regression analyze showed that the rate of using condoms in every commercial sex worker about female commercial sex workers who had more than 3 years practice time, had more than 8 about AIDS knowledge score, used condoms for preventing AIDS, used condoms if being gived more money was high relatively, OR value were 1.99 (95% CI: 1.17 - 3.41), 2.01 (95% CI: 1.04 - 3.86), 4.01 (95% CI: 1.18 - 13.61) and 2.95 (95% CI: 1.84 - 4.72) respectively. CONCLUSION: The female commercial sex workers in small service places had not long practice time, low education, low rate of used condoms. Practice time, AIDS knowledge score et al, were primary associated with using condoms.