Trends in HIV prevalence and risk behaviours among men who have sex with men from 2013 to 2017 in Nanjing, China: a consecutive cross-sectional survey.

OBJECTIVE:To examine the trends of HIV prevalence, risk behaviours and HIV testing among men who have sex with men (MSM) in Nanjing. DESIGN:Five consecutive cross-sectional surveys. SETTING:Nanjing, China. PRIMARY AND SECONDARY OUTCOME MEASURES:HIV and syphilis prevalence, HIV testing rate and factors associated with HIV infection; demographic characteristics and behaviours. RESULTS:649, 669, 577, 633, 503 MSM were recruited from 2013 to 2017. HIV prevalence was 9.9%, 12.3%, 12.5%, 9.8% and 10.1%, respectively. Syphilis prevalence decreased with a range from 10.6% to 5.6%. Risk behaviours like unprotected anal intercourse (UAI) and unprotected virginal sex in the past 6 months decreased, but multiple sex partners and ever used rush popper rose significantly. MSM tested for HIV in the previous year remained stable from 57.0% to 64.1% (P=0.633). Multivariate analysis showed that tested for HIV in the past year was protective factor against HIV infection. MSM who had UAI in the past 6 months, sex role as receptive and dual, diagnosed with sexually transmitted diseases (STDs) in the past year and currently syphilis infected were risk factors for HIV infection. CONCLUSIONS:We observed stable high HIV prevalence, a steady HIV testing rate, decreasing syphilis prevalence and UAI among MSM in Nanjing. However, rush popper use rose dramatically. The HIV preventive strategies for MSM including condom promotion, HIV testing expansion and reduction of rush popper use, STDs screening and standardised treatment should be strengthened

Poisson (co)homology and isolated singularities

To each polynomial \v\in\F[x,y,z] is associated a Poisson structure on \F^3, a surface and a Poisson structure on this surface. When \v is weight homogeneous with an isolated singularity, we determine the Poisson cohomology and homology of the two Poisson varieties obtained.Comment: 27 page

Great Walls from Mao to Now: A Biographical Perspective on Adult Education Inside Chinese Communist Revolution

From 1921 onwards, adult education was a vital corollary of Chinese Communist revolution. In 1954 Yao Zhongda lived near Mao in the Zhongnanhai and became Chief of the Bureau of Workers’ and Peasants Education. He is now 86 years old. The purpose of this study was to capture his biography and reflect on what it means for 21st century China. Data was secured during a 10-day Beijing interview session. Yao is an outstanding figure in Chinese adult education and today’s scholar-officials could learn a lot from him

Calculation of the spectrum of 12Li by using the multistep shell model method in the complex energy plane

The unbound nucleus $^{12}$Li is evaluated by using the multistep shell model in the complex energy plane assuming that the spectrum is determined by the motion of three neutrons outside the $^9$Li core. It is found that the ground state of this system consists of an antibound $1/2^+$ state and that only this and a $1/2^-$ and a $5/2^+$ excited states are physically meaningful resonances.Comment: 9 pages, 5 tables, 7 figures, printer-friendly versio

Cell contraction induces long-ranged stress stiffening in the extracellular matrix

Animal cells in tissues are supported by biopolymer matrices, which typically exhibit highly nonlinear mechanical properties. While the linear elasticity of the matrix can significantly impact cell mechanics and functionality, it remains largely unknown how cells, in turn, affect the nonlinear mechanics of their surrounding matrix. Here we show that living contractile cells are able to generate a massive stiffness gradient in three distinct 3D extracellular matrix model systems: collagen, fibrin, and Matrigel. We decipher this remarkable behavior by introducing Nonlinear Stress Inference Microscopy (NSIM), a novel technique to infer stress fields in a 3D matrix from nonlinear microrheology measurement with optical tweezers. Using NSIM and simulations, we reveal a long-ranged propagation of cell-generated stresses resulting from local filament buckling. This slow decay of stress gives rise to the large spatial extent of the observed cell-induced matrix stiffness gradient, which could form a mechanism for mechanical communication between cells