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Background: Measures to effectively expand tracing and testing to identify undiagnosed HIV infections are significant for the control of HIV/AIDS epidemic among men who have sex with men (MSM). We piloted a choice-based tracing and testing package aimed at improving partner tracing, uptake, and yield of HIV testing for sexual partners of newly diagnosed HIV-positive MSM. Methods: This package was piloted in the cities of Hangzhou and Ningbo, Zhejiang province, China from June 2014 to June 2016. The package adopted four modes: couples' HIV counseling and testing (CHCT), information assisted partner notification (IAPN), assisted HIV self-testing (HIVST) and patient referral. Data regarding sociodemographic factors and sexual behaviors between HIV-positive MSM and their sexual partners, as well as tracing and testing outcomes of each mode, were collected. Results: Among 2,495 newly diagnosed HIV-positive MSM, 446(18%) were enrolled as index cases (ICs) through two rounds of contact tracing. The ICs disclosed a total of 4,716 sexual partners, of whom 548 (12%) were reachable. The pilot study resulted in a testing uptake of 87% (478/548), and a yield of 16% (74/478) among sexual partners. The generalized linear mixed model showed that the odds of a reachable sexual partner enrolled via IAPN taking an HIV test were 290% greater than that of a partner traced via CHCT (95% CI: 1.6, 9.3). Conclusions: A choice-based tracing and testing package can feasibly expand HIV testing uptake and case finding among sexual partners of HIV-positive MSM. IAPN may be an acceptable option to reach sexual partners for whom limited contact information is available. [ABSTRACT FROM AUTHOR]

Rapid urbanization has produced serious heat effects worldwide. However, the literature lacks a detailed study on heat effects based on the directions and types of urban expansion. In this work, a typical city with an extremely hot summer climate, Hangzhou, was selected as a case study to determine the relationships between the urban heat-effect dynamics and spatiotemporal patterns of impervious surface expansion. Based on long-term Landsat imagery, this study characterized the spatiotemporal patterns of urban expansion and normalized surface temperatures in Hangzhou City from 2000 to 2020 using object-based backdating classification and a generalized single-channel algorithm with the help of a land-use transfer matrix, expansion index, and spatial centroids. Relevant policies, industries, and traffic networks were discussed to help explain urban expansion and thermal environment changes. The results demonstrated that in 2020, the area of impervious surfaces covered 1139.29 km2. The majority of the gains were in farmland, water, and forests, and the annual growth rate was 32.12 km2/year beginning in 2000. During the expansion of impervious surfaces, the city warmed at a slower rate, and more thermal contributions came from sub-urban areas. The southeast-oriented expansion of impervious surfaces was the key reason for the spatiotemporal dynamics of the urban heat effects. The dominant urban edge expansion intensified the local heat effects. This research provides a Landsat-based methodology for better understanding the heat effects of urban expansion. [ABSTRACT FROM AUTHOR]