Characteristics and trend of older men who have sex with men from 2010 to 2014 in Jiangsu province

目的:了解江苏省老年男男性行为(MSM)人群特征及变化趋势,为制定更有效的干预措施提供科学依据。方法:采用横断面调查对2010—2014年老年MSM进行监测,分析高危行为,HIV、梅毒感染状况的变化趋势。结果:共监测2010—2014年老年MSM 1 185例,浴池/桑拿/足疗/按摩等传统MSM活动场所所占比重从70.7%下降到29.3%,艾滋病相关知识知晓率、近6个月同性肛交发生率、同性肛交安全套坚持使用率分别从77.1%、55.4%、20.7%上升到91.2%、72.6%、38.5%,现症梅毒阳性率从21.7%下降到11.8%;性病、HIV阳性率未见明显下降趋势。结论:江苏老年MSM人群性活跃度高,安全套坚持使用率低,HIV阳性率维持高位。对这类人群应加强安全套推广,开展新的综合干预方式。Objective: To understand the characteristics and trend on HIV related high risk behaviors,HIV and syphilis prevalence among old men who have sex with men( MSM) in Jiangsu province from 2010 to 2014,so as to provide information for the development of intervention strategies for old MSM. Methods: Using cross sectional study,we sampled 1 185 old MSM between 2010 and 2014. We analyzed the trend on HIV related risk behaviors,HIV and syphilis prevalence. Results: The proportion of traditional sample sites,such as bath / sauna / massage room,decreased from 70. 7% to 29. 3%. The rate of knowledge,attitude,practice( KAP) related to HIV,anal sex in latest six months,and habitual condom use between old MSM increased from 77. 1%,55. 4%,20. 7% to91. 2%,72. 6%,38. 5% separately. The prevalence of syphilis decreased from 21. 7% to 11. 8%. There was no significant difference on the trend of HIV and sexually transmitted diseases. Conclusions: The rates of sexually activity and HIV prevalence were pretty high,but the rate of habitual condom use was low in old MSM. Based on the results,condom use should be strengthened and new intervention measures should be developed

Prediction of Energy Resolution in the JUNO Experiment

International audienceThis paper presents the energy resolution study in the JUNO experiment, incorporating the latest knowledge acquired during the detector construction phase. The determination of neutrino mass ordering in JUNO requires an exceptional energy resolution better than 3% at 1 MeV. To achieve this ambitious goal, significant efforts have been undertaken in the design and production of the key components of the JUNO detector. Various factors affecting the detection of inverse beta decay signals have an impact on the energy resolution, extending beyond the statistical fluctuations of the detected number of photons, such as the properties of liquid scintillator, performance of photomultiplier tubes, and the energy reconstruction algorithm. To account for these effects, a full JUNO simulation and reconstruction approach is employed. This enables the modeling of all relevant effects and the evaluation of associated inputs to accurately estimate the energy resolution. The study reveals an energy resolution of 2.95% at 1 MeV. Furthermore, the study assesses the contribution of major effects to the overall energy resolution budget. This analysis serves as a reference for interpreting future measurements of energy resolution during JUNO data taking. Moreover, it provides a guideline in comprehending the energy resolution characteristics of liquid scintillator-based detectors