An exploratory survey of money boys and HIV transmission risk in Jilin Province, PR China

This report represents the first exploratory study of Chinese men who provide commercial sex services to other men ("money boys") in Jilin Province, People's Republic of China, through a convenience sample drawn from Changchun and Jilin City. A total of 86 active money boy participants (Changchun, n = 49; Jilin City, n = 37) were surveyed concerning background and demographics, basic HIV transmission knowledge, and sexual practices. The survey indicated that while Jilin Province money boy behavior matches other studies concerning propensity to high risk behavior and significant bridging potential, the Jilin money boys, unlike previous studies, exhibited a high level of basic HIV/AIDS transmission knowledge. In spite of this level of knowledge, none of the participants reported always using a condom in their sexual activities. They also exhibited a high level of awareness of voluntary counseling and testing available in the province, yet relatively few had availed themselves of these services. These preliminary findings will be used as a baseline and springboard for continuing study in the Jilin Province money boy community. Even now, however, it is becoming clear that the dynamics of male commercial sex work may vary greatly depending upon local influences, and will necessitate that future interventions are highly tailored to area-specific circumstances

Emerging Trends of HIV Drug Resistance in Chinese HIV-Infected Patients Receiving First-Line Highly Active Antiretroviral Therapy: A Systematic Review and Meta-Analysis

Background. Highly active antiretroviral therapy (HAART) has led to a dramatic decrease in AIDS-related morbidity and mortality through sustained suppression of human immunodeficiency virus (HIV) replication and reconstitution of the immune response. Settings like China that experienced rapid HAART rollout and relatively limited drug selection face considerable challenges in controlling HIV drug resistance (DR)

Millimeter-wave 39 GHz 4x4 Phased Antenna Array with Embedded Near-field Probing Antenna for Performance Enhancement

Beamforming arrays are a vital technology for millimeter-wave (mm-wave) wireless communication systems. A large amount of research and an increasing number of phased array prototypes have been developed which provide high data rates and low latency. However, as sub-6 GHz bands have limited bandwidth and crowded spectrum occupation, mm-wave phased arrays are more desirable for future generation systems. Yet, there are challenges with current phased array technologies that need to be addressed by researchers. Linear power amplifier response, radio frequency front-end calibration, and affordable prototyping costs are the main challenges that must be taken into consideration when designing arrays for mm-wave systems. This thesis presents approaches to these challenges and trade-offs and proposes an optimized design solution. A novel wideband near-field (NF) probing antenna is proposed that can be embedded in mm-wave phased arrays to provide the feedback signal path necessary for carrying out array calibration and digital pre-distortion training. Specifically, the topology and layout of the proposed NF probing antenna have been carefully devised to achieve a coupling to its surrounding antenna elements with flat magnitude and constant group delay. A proof-of-concept 4x4 linear-polarized active phased array prototype with embedded NF probing antennas is designed to operate over 37-41 GHz. Measurements confirm the negligible impact of the NF probing antennas on the antenna array's radiation pattern, and the array prototype was successfully used to train a digital pre-distortion function which enabled the effective isotropic radiated power to be increased from 32 dBm to 34.3 dBm, while maintaining an error vector magnitude below 3.5%, when the array was steered from -50 degrees to +50 degrees

Thermodynamic Analysis of Pyrolusite for Dry Flue Gas Desulfurization

Various approaches to flue gas desulfurization by low-grade manganese and high efficiency desulfurization in sintering enterprises were investigated, and the predominance areas of the Mn/Fe-S-O system were constructed in this paper. Additionally, the areas in different temperatures were established based on the thermodynamic properties achieved from manuals. From the view of thermodynamics, manganese oxides were suitable and feasible for desulfurization at an appropriate temperature range from 393 K to 453 K (120 °C to 180 °C), which means that the SO2 of sintering flue gas could be removed directly without further cooling or heating. The analysis often showed that there was an overlap area of the Mn-S-O and Fe-S-O system, indicating that it would be a coexistence stability region of MnSO4 and Fe2O3, which provided a possibility of desulfurization by selective salvation without the sulfate and sulfide of iron forming. More importantly, the predominance areas of Mn/Fe-S-O would offer an attractive way of determining optimum experimental conditions for dry desulfurization by low-grade manganese resources

Effect of temperature on galvanic corrosion of Al 6061-SS 304 in nitric acid

Nitrogen tetroxide (N2O4) is commonly used as an oxidizer for bipropellant liquid, and galvanic corrosion of its storage tanks was a serious problem. The immersion and electrochemical experiments of Al 6061-SS 304 galvanic pair were carried out in 30% nitric acid at different temperatures. The accelerated galvanic corrosion of Al 6061 and the effect of different temperatures on its corrosion behavior were studied. The surface morphology, number of corrosion pits and electrochemical parameters of Al 6061 before and after corrosion were measured and analyzed by means of SEM, EDS and electrochemical methods. The results show that when Al 6061 was coupled with SS 304 at 10 °C, the driving potential difference between them reached 366 mVSCE, and Al 6061 was used as the corrosion anode. In the SEM images, three kinds of galvanic corrosion phenomena can be seen obviously after coupling. When the temperature is between 10 °C and 30 °C, the corrosion pits are mainly composed of aluminum matrix coupled with second phase particles with positive or negative volt potential relative to it. When the temperature was between 40 °C and 50 °C, the corrosion pits showed mainly intergranular corrosion at the interface of different grains. At the same time, the increase in temperature led to the decrease in galvanic potential and the change in corrosion current. There was no simple linear relationship between galvanic current and temperature, but it satisfied a certain quantitative relationship, and the theoretical ratio was highly consistent with the actual ratio by the K–S test

Research Progress on Resource Treatment and Recycling of Solid Waste Containing Chromium

In recent years, China has paid more and more attention to ecological and environmental protection, and the treatment of solid waste during industrial production has become more important. For example, stainless steel production industry, electroplating industry, chromium salt production industry, etc., will produce a large amount of chromium-containing solid waste. Long-term accumulation will not only occupy land resources but also cause serious harm to the environment. Therefore, it is particularly important to develop more effective methods for recycling and processing chromium-containing solid waste. This article summarizes the current situation of chromium ore resources in China, predicts the demand for chromium ore in the next few years, expounds the current situation and hazards of chromium-containing solid waste, and summarizes the new domestic and foreign chromium-containing solid waste treatment technologies in recent years. Research and progress in the recycling of chromium-containing solid waste, introducing the advantages and disadvantages of different treatment methods, in order to find a better way to recover and treat chromium-containing solid waste in the future

Characterization of Ni3Sn intermetallic nanoparticles fabricated by thermal plasma process and catalytic properties for methanol decomposition

The intermetallic compound Ni3Sn has potential for application in hydrogen production as a catalyst. Herein, we synthesized Ni3Sn nanoparticles through a thermal plasma process. We characterized the nanoparticles by synchrotron radiation X-ray diffraction and transmission electron microscopy analyses, and analyzed their catalytic properties for methanol decomposition in a temperature range of 513 to 793 K. The Ni3Sn nanoparticles showed a higher selectivity to H2 and CO than pure Ni nanoparticles, but a relatively lower catalytic activity for methanol decomposition compared to pure Ni nanoparticles. Density functional theory calculations revealed that the activation energy barrier for CO dissociation on Ni3Sn (001) was 396 kJ/mol, which was higher than that for Ni (111). Moreover, the activation energy barrier for OH formation on Ni3Sn (001) was 229 kJ/mol, which was significantly higher than that for Ni (111). This supported the experimental results and confirmed that the Ni3Sn catalyst suppresses the formation of carbon and H2O, compared to Ni catalyst