Interest in the ‘Test and Treat’ strategy for HIV prevention among men who have sex with men living in Bangkok

Background: The current HIV epidemic in Thailand is primarily driven by new cases among men who have sex with men (MSM). HPTN052 study demonstrated 96% efficacy of immediate antiretroviral therapy (ART) to reduce HIV transmission among serodiscordant heterosexual couples. As a result, universal HIV testing and immediate ART has emerged as a strategy to reduce HIV transmission in certain at-risk populations. The acceptability of this strategy, however, is unknown in MSM. Methods: From August 2011-March 2012, we conducted a cross-sectional study using self-administered questionnaires to assess attitudes towards universal HIV testing and immediate ART among MSM VCT clients in Bangkok. Participants were asked to complete the questionnaires prior to and after knowing their HIV status. The study was approved by the Institutional Review Board of the Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand. Results: Of 342 MSM, the median age (IQR) was 26 (22–31) years, and 34.2% had bachelor's degree or higher. Previous HIV testing was reported by 69.9%, 35.2% of which had HIV testing annually. The most common reasons for previous HIV testing included perceived risk behaviors (63.6%), annual health checkup (26.4%), and partner's request (13.8%). Prior to receiving pre-test counseling, 74.4% expressed interest to get regular HIV testing. Health benefits from testing (59.6%), free testing (36.5%), and speedy service (35.7%) were the most common persuasive reasons to come for regular HIV testing. Longevity (73.1%) and prevention of HIV transmission to others (58.4%) were reasons for interest in immediate ART (if tested positive) program while costs (37.0%) and life-long burden (36.7%) were cited as main barriers. Among MSM who tested HIV-positive (n=45, 13.2%), the interest to participate in immediate ART program was very high both before and after knowing their HIV status (86.7% vs 93.3%, p=0.371). Among HIV-negative MSM, the interest to participate in regular HIV testing program significantly increased after knowing HIV status (83.4% vs 77.0%, p<0.001). Conclusions: MSM in Bangkok showed high level of interest in the “Test and Treat” strategy for HIV prevention. Knowing one's HIV status affected the interest to access regular HIV testing program

Fast Transporting ZnO–TiO₂ Coaxial Photoanodes for Dye-Sensitized Solar Cells Based on ALD-Modified SiO₂ Aerogel Frameworks

A doubly coaxial photoanode architecture based on templated SiO₂ aerogels was fabricated on transparent conducting oxides for use in dye-sensitized solar cells (DSSCs). These templates were coated with ZnO <i>via</i> atomic layer deposition (ALD) to yield an electronically interconnected, low-density, high-surface-area, semiconductor framework. Addition of a thin conformal layer of a second metal oxide (alumina, zirconia, or titania) <i>via</i> ALD was found to suppress the dissolution of ZnO that otherwise occurs when it is soaked in alcohol solutions containing acidic dyes used for sensitization or in acetonitrile solutions containing a pyridine derivative and the iodide/tri-iodide (I^–/I^–₃) redox shuttle. Electron transport in SiO₂–ZnO–TiO₂ photoelectrodes was found to be nearly 2 orders of magnitude faster than in SiO₂–TiO₂ structures, implying that the interior ZnO sheath serves as the primary electron conduit. In contrast, rates of electron interception by the oxidized form of the redox shuttle were observed to decrease when a TiO₂ shell was added to SiO₂–ZnO, with the decreases becoming more significant as the thickness of the titania shell increases. These effects lead to improvements in efficiency for DSSCs that utilize I^–/I^–₃, but much larger improvements for DSSCs utilizing ferrocene/ferrocenium, a notoriously fast redox shuttle. For the former, overall energy conversion efficiencies maximize at 4.0%. From a variety of experiments, the primary factor limiting aerogel-based DSSC performance is light loss due to scattering. Nevertheless, variants of the doubly coaxial structure may prove useful in devising DSSCs that can achieve excellent energy conversion efficiencies even with fast redox shuttles