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Film morphology of emissive layers is crucial to the performance and stability of solution-processable organic light-emitting diodes (OLEDs). Compared to the interpenetration of conjugated polymer chain, small molecular emitter with a flexible side chain always presents easily aggregation upon external treatment, and caused π-electronic coupling, which is undesirable for the efficiency and stability of deep-blue OLEDs. Herein, we proposed a side-chain coupling strategy to enhance the film morphological an emission stability of solution-processable small molecular deep-blue emitter. In contrary to “parent” MC8TPA, the crosslinkable styryl and vinyl units were introduced as ended unit at the side-chain of CmTPA and OEYTPA. Interestingly, CmTPA and OEYTPA films present a relatively stable morphology and uniform deep-blue emission after thermal annealing (160 °C) in the atmosphere, different to the discontinuous MC8TPA annealed film. Besides, compared to the CmTPA and OEYTPA ones, serious polaron formation in the MC8TPA annealed film also negative to the deep-blue emission, according to transient absorption analysis. Therefore, both CmTPA and OEYTPA annealed film obtained at 140 °C present an excellent deep-blue ASE behavior with a 445 nm, but absence for MC8TPA ones, associated with the disruption of annealed films. Finally, enhancement of device performance based on CmTPA and OEYTPA film (∼40%) after thermal annealing with a similar performance curves also confirmed the assumption above. Therefore, these results also supported the effectiveness of our side-chain coupling strategy for optoelectronic applications.

Introduction: To control the spread of human immunodeficiency virus (HIV) among sero-discordant couples, we explored the HIV seroconversion and its contributing factors. Methodology: We recruited negative partners in HIV sero-discordant couples to established a prospective cohort between January 2010 and June 2015 from areas with severe HIV epidemic in Xinjiang. Follow up once every 3 months, serological tests and risk behavior surveys every 6 months. Variables were screened by LASSO regression and a Cox proportional hazards model was established. Results: A total of 1162 negative partners of sero-discordant couples were recruited. The seroconversion occurred in 42 negative partners during follow-up period, with a seroconversion rate of 2/100 (95% CI = 1.21-2.27), and the median time for seroconversion was 0.92 years. The Cox model showed that frequency of sexual behavior for nearly six months, consistent condom use, knowledge of the transmission route for HIV, a history of sexually transmitted diseases, recent CD4 + T lymphocyte count were all significant contributing factors to the seroconversion in negative partner of HIV sero-discordant couples. In addition, the Cox model was used to evaluate the risk factors of seroconversion for HIV negative partners. Conclusions: The seroconversion rate of HIV negative partners in Xinjiang was lower. The LASSO Cox model may accurately predict the risk of HIV transmission in sero-discordant couples.

The Xinjiang Uygur Autonomous Region (XUAR) in the northwest was ranked sixth in the numbers of reported cases of (HIV) in China up to the end of December 2017. By that time, HIV had affected 0.23% of the total population (56,588 cases had been reported since 1995), the province with third highest cumulative incidence in China. The HIV epidemic in XUAR has similar features to other provinces where the use of non-sterile injecting equipment by people who inject drugs (PWID) generated the development of the epidemic. These similarities included age and gender distribution. The majority of people living with HIV (PLWH) were 20–39 years of age at diagnosis, and women made up 36.7% of reported cases. Sexual transmission was the major transmission route for both women (85.4%) and men (60%) as of 2017. The scale of sexual transmission for women was a specific feature of the epidemic in XUAR. Interventions have had a positive impact. From 2002 to 2017, there were reductions in the numbers of HIV infection, in all of the sentinel surveillance groups. The most significant reduction was among PWID. In 2002, 52.6% tested positive, while in 2017, only 8.15% tested positive. FSW and clients attending clinics for sexually transmitted infections had low prevalence of HIV infection, less than 1% consistently. Male-male sexual transmission is becoming an important transmission route—7.4% of sexual transmissions for men were from male-male sex, and the annual sero-conversion rate in this group was about 5% by 2017. The major challenges in addressing prevention is targeting and focusing interventions to meet the specific needs of ethnic groups and to further extend interventions into key populations at higher risk.

(See the Editorial Commentary by Sugandhi and Harwell on pages 745–6.) Background. The aim of this study was to describe 3-year mortality rates, associated risk factors, and longterm clinical outcomes of children enrolled in China’s national free pediatric antiretroviral therapy (ART) program. Methods. Records were abstracted from the national human immunodeficiency virus (HIV)/AIDS case reporting and national pediatric ART databases for all HIV-positive children ≤15 years old who initiated ART prior to December 2010. Mortality risk factors over 3 years of follow-up were examined using Cox proportional hazards regression models. Life tables were used to determine survival rate over time. Longitudinal plots of CD4 + T-cell percentage (CD4%), hemoglobin level, weight-for-age z (WAZ) score, and height-for-age z (HAZ) score were created using generalized estimating equation models. Results. Among the 1818 children included in our cohort, 93 deaths were recorded in 4022 child-years (CY) of observed time for an overall mortality rate of 2.31 per 100 CY (95% confidence interval [CI], 1.75–2.78). The strongest factor associated with mortality was baseline WAZ score

Objective To assess the predictors and prevalence of HIV infection among injection drug users in highly endemic regions along major drug trafficking routes in three Chinese provinces. Methods We enrolled participants using community outreach and peer referrals. uestionnaire-based interviews provided demographic, drug use, and sexual behavior information. HIV was tested via ELISA and syphilis by RPR. Results Of the 689 participants, 51.8% were HIV-infected, with persons living in Guangxi having significantly lower prevalence (16.4%) than those from Xinjiang and Yunnan (66.8% and 67.1%, respectively). Syphilis seropositivity was noted in 5.4%. Longer duration of IDU, greater awareness of HIV transmission routes, and living in Xinjiang or Yunnan were associated with HIV seropositivity on multivariable analysis. Independent risk factors differed between sites. In Guangxi, being male and having a longer duration of IDU were independent risk factors for HIV infection; in Xinjiang, older age and sharing needles and/or syringes were independent factors; in Yunnan, more frequent drug injection, greater awareness of HIV transmission routes, and higher income were independent predictors of HIV seropositivity. Conclusion Prevalence rates of HIV among IDUs in China are more than two out of three in some venues. Risk factors include longer duration of IDU and needle sharing. Also associated with HIV were factors that may indicate some success in education in higher risk persons, such as higher knowledge. A systemic community-level intervention with respect to evidenced-based, population-level interventions to stem the spread of HIV from IDU in China should include needle exchange, opiate agonist-based drug treatment, condom distribution along with promotion, and advocacy for community-based VCT with bridges to HIV preventive services and care.

To detect recent infection in injection drug users (IDU) using the HIV-1 subtypes B, E, and D IgG-capture enzyme immunoassay (BED-CEIA) and estimate HIV-1 incidence in the IDU population in three cities of China.HIV-1-positive samples from IDU surveillance sentinel sites were collected for BED-CEIA, including 215 from city C (2001-2006), 433 from city D (2005), and 912 from city E (2000-2003). All 1560 samples were confirmed HIV positive with Western blot or alternative strategy.HIV-1 incidence was calculated with BED-CEIA statistics software.City C: Annualized HIV-1 incidence among IDU of surveillance sentinel sites was 0.57-0.93% from 2000 to 2001, and approximately 1.0% from 2004 to 2006. City D: In IDU surveillance sentinel sites in 2005, the HIV-1 incidence was estimated to be 9.6%, whereas the incidence in all drug users was 2.1%. City E: IDU sentinel surveillance indicated a slight decrease in HIV-1 incidence from 9.2% in 2000 to 7.9% in 2003.The HIV-1 incidence in IDU in city C was stable and relatively low. In contrast, there is a high HIV-1 incidence among IDU in cities D and E. The adjusted BED-CEIA estimated incidence rates indicate clearly that interventions must be strengthened continuously in IDU, especially in two Chinese cities.