Human immunodeficiency virus (HIV) testing is confirmed as a preventive strategy for HIV control. However, the testing rate and risk behaviors of HIV-negative men who have sex with men (MSM) remain unclear. We aimed to examine factors associated with HIV testing and high-risk behaviors among HIV-negative MSM. From July 2016 to June 2017, participants were recruited by snowball sampling from WeChat groups, bars, and other venues. HIV testing was performed to exclude HIV-positive MSM. Face-to-face questionnaires regarding HIV testing and high-risk behaviors were conducted; 988 MSM were included, and 57.1% of participants underwent HIV testing in the past year. The proportion of high-risk behaviors was 49.9%. Factors associated with HIV testing were bisexual orientation, substance use to adjust psychiatric disorders, and receiving acquired immune deficiency syndrome (AIDS) interventions. Being married, bisexual orientation, and receiving AIDS interventions were risk factors for high-risk sexual behaviors, while college or higher degree was a protective factor. We determined that HIV transmission factors are widespread, and the rate of HIV testing is relatively low. Attention should be given to marital status, using substances to adjust psychiatric disorders, or bisexual HIV-negative MSM, and AIDS interventions should be strengthened to promote HIV testing and reduce high-risk behaviors.

BackgroundHIV testing and early linkage to care are critical for reducing the risk of HIV transmission. HIV self-testing (HIVST) is an useful tool for increasing HIV testing frequency.This study aimed to investigate HIVST rates among men who have sex with men (MSM), the characteristics of MSM who had HIVST, and factors associated with HIVST uptake among MSM in Ningbo, China. MethodsA cross-sectional study was conducted from April to October 2019 in Ningbo,China. Participants were aged at least 18 years and having had sexual contact with men in the past year. Proportions were used for categorical variables. Adjusted Odds Ratio (AOR) and 95% Confidence Interval (CI) for characteristics associated with HIVST uptake was processed by multiple logistic regression models.ResultsAmong a sample of 699 MSM recruited, 38.2% had reported previous use of an HIV self-test kit. A greater proportion of HIVST Users had a higher frequency of HIV testing(≥2 times: 70.0% versus 41.2%, p<0.001) in the past one year. Factor associated with HIVST uptake was gay apps use(AOR=1.86,CI=1.13-3.05), multiple male sex partners (AOR=1.90,CI=1.29-2.80), frequency of male-male sexual contact ≥1 times per week(AOR=1.86, CI=1.30-2.66), syphilis infection(AOR=5.48, CI=2.53-11.88).ConclusionsFurther HIVST education should be strengthened for school-aged children and teenagers, and free HIVST kits may be provided to low-income high-risk MSM through gay apps and NGOs to achieve the increased HIV testing frequency.

Background HIV testing and early linkage to care are critical for reducing the risk of HIV transmission. HIV self-testing (HIVST) is a useful tool for increasing HIV testing frequency.This study aimed to investigate HIVST rates among men who have sex with men (MSM), the characteristics of MSM who had HIVST, and factors associated with HIVST uptake among MSM in Ningbo, China. Methods A cross-sectional study was conducted from April to October 2019 in Ningbo,China. Participants were aged at least 18 years and having had sexual contact with men in the past year. Proportions were used for categorical variables. Adjusted Odds Ratio (AOR) and 95% Confidence Interval (CI) for characteristics associated with HIVST uptake was processed by multivariable logistic regression models. Results Among a sample of 699 MSM recruited, 38.2% had reported previous use of an HIV self-test kit. A greater proportion of HIVST users had a higher frequency of HIV testing (≥ 2 times: 70.0% versus 41.2%, p < 0.001) in the past 1 year. The odds of older age (30–39 years: AOR = 0.49, CI 0.32–0.76; more than 40 years: AOR = 0.07, CI 0.04–0.14, compared to 18–29 years), bisexual (AOR = 0.49, CI 0.29–0.84) were lower among HIVST users,and were higher among MSM who were higher education level (high school: AOR = 2.82, CI 1.70–4.69, compared to middle school or less), gay apps use (AOR = 1.86, CI 1.13–3.05), multiple male sex partners (AOR = 1.90, CI 1.29–2.80), frequency of male–male sexual contact ≥ 1 times per week (AOR = 1.86, CI 1.30–2.66), syphilis infection (AOR = 5.48, CI 2.53–11.88). Conclusions Further HIVST education should be strengthened for school-aged children and teenagers, and free HIVST kits may be provided to high-risk MSM through gay apps and CBO to achieve the increased HIV testing frequency.

It is difficult to reclose transmission line successfully after tree fault occurs, which is easy to cause line outage. At present, most of the existing research focuses on the diagnosis and disposal of tree faults, while the mechanism of tree faults is relatively rare. Firstly, the formation process of tree faults and the typical discharge characteristics at different tree height stages are analyzed. Then, the process of tree-wire gap discharge at different stages is simulated in laboratory environment. With trees approaching transmission lines, corona discharge, hidden discharge and flashover discharge occur in turn, and the discharge increases from weak to strong, and the amplitude increases, while the frequency of discharge waveform tends to decrease.

Background: The human immunodeficiency virus (HIV) testing had been confirmed as a preventive strategy for HIV control. The testing rate and risk behavior of HIV-negative men who have sex with men (MSM) are still unclear. The aim of this study was to examine the factors associated with HIV testing, and high-risk behavior among HIV-negative MSM in Ningbo, China. Methods: This cross-sectional study was conducted between July 2016 and June 2017. Using snowball sampling to recruit MSM. Participants were recruited from Blued (an app for the gay community), QQ/Wechat groups, voluntary counseling and testing clinics, baths, bars, and other types of venues. Before the interview, all participants had HIV testing. MSM were included if their result of HIV screening test were negative. Face-to-face questionnaires were conducted mainly focused on HIV testing in the past year and high-risk behavior in the past 3 months. Results: In total, 988 MSM were included, 57.1% (564/988) of participants had HIV testing in the past year. The proportion of high-risk sexual behavior was 49.9%. Factors associated with HIV testing were bisexual orientation (adjusted odds ratio [AOR] 0.57, 95% confidence interval [CI] 0.42–0.78), drug use to adjust psychological abnormalities (AOR 1.39, 95 CI 1.04–1.85), and receiving HIV interventions (AOR 4.03, 95 CI 3.00–5.42). Being married (AOR 1.72, 95% CI 1.15–2.58), bisexual orientation (AOR 2.13, 95% CI 1.54–2.95), and receiving HIV interventions (AOR 1.65, 95% CI 1.25–2.20) were risk factors for high-risk sexual behavior, while college degree or above (AOR 0.52, 95% CI 0.35–0.77) were the protective factor. Conclusion: We revealed low rate of HIV testing and high rate of risk sexual behavior among HIV-negative MSM in Ningbo. HIV transmission factors are widespread, but the proportion of 90% diagnosed for HIV are still a huge challenge in this population. Attention should be given to married, using substances or bisexual HIV-negative MSM, and HIV intervention should be strengthened to promote HIV testing and reduce risk behavior.