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Antiretroviral therapy (ART) has been shown to improve survival of patients with Human Immunodeficiency Virus (HIV) infection and to reduce HIV-1 transmission. Therefore, the Chinese central government initiated a national program to provide ART free of charge to HIV-1 patients. We conducted a cross-sectional survey in Jiangsu province to determine the level of drug resistance (DR) in HIV-1 infected patients and the correlates of DR in virological failures in 2012. Approximately 10.4% of the HIV-1 patients in the study experienced virological failure after one year of ART and were divided into drug sensitive and drug resistant groups based on genotype determination. The viral loads (VLs) in the drug resistant group were significantly lower than the drug sensitive group. There were two independent predictors of virological failure: male gender and increasing duration of treatment. The primary mutations observed in the study were against nucleoside reverse transcriptase inhibitors (NRTIs) which were M184V (79.45%) and K103N (33.70%) in nonnucleoside reverse transcriptase inhibitors (NNRTIs). The overall rate of DR in Jiangsu province is still relatively low among treated patients. However, close monitoring of drug resistance in male patients in the early stages of treatment is vital to maintaining and increasing the benefits of HIV ART achieved to date.

Because loess underground erosion is one of the major engineering geological problems in loess areas of China, foundation loess of the Zichang-Yongping section of West-East Gas Pipelines is taken as the research object. The soil-water characteristic curve (SWCC) and hydraulic conductivity function (HCF) of samples have been obtained by laboratory tests, and on this basis, seepage field numerical simulations of loess foundation with and without the pipelines have been processed by the finite-element method. Critical groundwater seepage velocity of underground erosion and the relationship between groundwater seepage velocity and underground erosion velocity have been tested by self-made instruments. Results of tests and numerical simulation indicate that the pipelines not only change the original seepage field of a loess foundation, but also accelerate the underground erosion of a loess foundation. Loess on the top and upstream groundwater side of pipelines will be eroded first, finally causing the failure of foundation and the exposure of pipelines. The combination of soil solidified material and revegetation is suggested as an effective and durable solution to deal with the underground erosion problem of loess pipeline foundations.

Shear behavior of rock mass greatly depends upon the rock joint roughness which is generally characterized by anisotropy, scale effect and interval effect. A new index enabling to capture all the three features, namely brightness area percentage (BAP), is presented to express the roughness based on synthetic illumination of a digital terrain model derived from terrestrial laser scanner (TLS). Since only tiny planes facing opposite to shear direction make contribution to resistance during shear failure, therefore these planes are recognized through the image processing technique by taking advantage of the fact that they appear brighter than other ones under the same light source. Comparison with existing roughness indexes and two case studies were illustrated to test the performance of BAP description. The results reveal that the rock joint roughness estimated by the presented description has a good match with existing roughness methods and displays a wider applicability.

The coarse particles (defined as particle size between 0.25 mm and 2 mm here) in sliding zones of Huangtupo landslide in Three Gorges Reservoir Area are taken as study objects. Particle size distribution and particle profiles of samples are firstly obtained through sieving tests and digital imaging respectively. Combined with fractal theory, the fractal dimensions of particle size distributions and particle profiles are calculated quantitatively. Scanning electron microscopy and energy disperse spectroscopy are employed to capture the micrograph and test the mineral composition of samples. Tests and analysis results indicate that the particle size distributions and profiles of samples have fractal characteristics, and the fractal dimensions can be used as quantitative analytical index for the evolution of sliding zones. As the continuous development of sliding zones, the particle mass – size fractal dimension increase and the profile fractal dimension decrease. The special surface characteristics of particles can also indirectly reflect the stress and deformation conditions during the failure and evolution of the sliding zones.

Aiming at a femoral entity, a three-dimensional modeling method is presented. Using CT technology to scan the femur, the extraction method and smoothing process method of the inner and outer contour lines are studied. The inner and outer contour lines are fitted to surfaces by NX7.0, and the three-dimensional model of the femur can be obtained by suturing all the curve faces. The studies show that, the contour lines of equal spaced data points are smooth, the sample point spacing and the output gap will affect the size and accuracy of the model, single fitting method can effectively eliminate the phenomenon of wrinkle between curved faces. The three-dimensional modeling method could be used to guide the design of prosthesis and the operation of surgery.

This study aimed to investigate the neural differentiation of human umbilical cord mesenchymal stem cells (hUCMSCs) under the induction of injured neural cells. After in vitro isolation and culture, passage 5 hUCMSCs were used for experimentation. hUCMSCs were co-cultured with normal or Aβ1-40-injured PC12 cells, PC12 cell supernatant or PC12 cell lysate in a Transwell co-culture system. Western blot analysis and flow cytometry results showed that choline acetyltransferase and microtubule-associated protein 2, a specific marker for neural cells, were expressed in hUCMSCs under various culture conditions, and highest expression was observed in the hUCMSCs co-cultured with injured PC12 cells. Choline acetyltransferase and microtubule-associated protein 2 were not expressed in hUCMSCs cultured alone (no treatment). Cell Counting Kit-8 assay results showed that hUCMSCs under co-culture conditions promoted the proliferation of injured PC12 cells. These findings suggest that the microenvironment during neural tissue injury can effectively induce neural cell differentiation of hUCMSCs. These differentiated hUCMSCs likely accelerate the repair of injured neural cells.

Roller shapes play a very critical role in the performance of antibacklash double-roller enveloping hourglass worm (ADEHW) gears; however, their influence is seldom reported in the literature. Based on the theories of differential geometry and gear meshing, this paper presents generic models of meshing characteristics for ADEHW gears, including both the contact curve and the tooth profile. We present different meshing functions and their derivatives with respect to each drive type and their associated roller shapes. We also compare the effects of contact curve, tooth profile, tooth undercutting, lubrication angle, induced normal curvature, and autorotation angle in order to design the most optimal tooth profile for the ADEHW gear. Finite element analysis was also conducted in order to minimize the contact stresses as a function of the roller type. Our results show that a spherical roller has the smallest value among the three available meshing roller shapes but is the most difficult design to procure. A cylindrical roller, however, incurs the greatest contact stress.

PZ-30 excavator is a small tonnage miniature excavator. Due to the need of working condition, this machine should be long-term mount hydraulic breaking hammer. In order to reduce the damage on excavator boom caused by vibration and optimize the design of boom, it is needed to conduct modal analysis of boom. This paper uses the Algor finite element simulation software, combined with the actual working environment of the excavator, to conduct modal analysis of the boom 3D model. In this paper, it calculates five orders resonance and relates main shape of vibration. Thus, it can provide advice for the use of the excavator and theoretical basis for design improvement of the boom.

Arm power assistant system is a typical Man-machine integration system. Whether it has the ability of power assist eventually depends on whether its control system can make fast and accurate response to the information, which is collected by the perceptual system. Therefore, a fuzzy self-adaptive PID control, which combines the fuzzy theory and PID control theory organically, has been applied to the arm power assistant system. Because the new strategy has the ability of real-timely and on line adjusting PID control parameters, it meets the requirements of the complicated controlling process better. Through the simulation analysis in the Simulink, we know fuzzy self-adaptive PID controller is much better than the traditional PID controller. Its response speed is faster, and it can meet the requirements of real-time and on-line adaptive control.

Aimed at numerous joint freedom of humanoid robot and the complex control situation of motor, this paper presents a hierarchical control structure and a modular design project for bottom joint controller. To combine the capability of high-speed data processing of DSP and the predominant control performance of 8-bit MCU, the design chooses TMS320F2812 for coordination layer and P89LPC9201 for execution layer, making the DC motors stable rotation. There are two Event Managers in TMS320F2812, so the DSP could control the joints of two legs at the same time. Coordination layer and execution layer could realize communication through UART. The incremental PID algorithm is used in the control strategy by stages. Simulation result shows that this method is rapid, stable and accurate.

Based on the DSP controlling of TI company kind of design of wheeled mobile robot platform design, the purpose is to make the control system of soccer robber more stable and efficient The design makes full use of the resources of TMS320F2812 event manager constitutes electric machine control module, ultrasonic ranging module, infrared communication module and temperature compensation module. Adopting the PWM channels in event manager controls BLDC motors on the two wheels around .Through the I/O port constitutes ultrasonic ranging and infrared communication module. There are some improvements on the design of ultrasonic ranging structure in this paper, collect data frequently and optimize the data, which strengthen the initiative control ability about the robot dolly itself and improve the sensitivity and accuracy in obstacle avoiding and navigation .The design decreases the outer circuit and reduces the loss of hardware system, while make the system more compact and higher integration. The design also provides a better platform for the further development.

Wireless Audio Sensor Networks (WASNs) can provide event detection, object tracking and audio stream monitoring through cooperative audio sensor nodes. Extensive researches have focused on sound detection and source localization, but little work is on the monitoring and recovery of audio stream. To clearly reconstruct the real-time audio stream from WASNs, both the quantity and quality of samples provided by sensor nodes should be carefully considered. In this work, we propose a novel approach termed "adaptive sampling and diversity reception", which can significantly reduce the energy consumption of network while maintaining high accuracy of audio stream. On one hand, by selectively picking sampling nodes and adaptively adjusting their sampling rates, sufficient samples arrive at the fusion node for high recovering fidelity. On the other hand, through Maximal-Ratio-Combining(MRC)-like signal fusion scheme at the fusion node, the signal-to-noise ratio (SNR) of combined audio is further improved. Meanwhile, we propose a heuristic algorithm of sampling rate assignment which can select a set of optimal sampling nodes and hence minimize the energy consumption on data transmission. Analytically and experimentally, we show that the proposed scheme can improve the signal recovering fidelity tremendously with low energy cost.

Municipal pipeline construction project plays a very important role in the city. The quality of the construction is contacted with urban development and people's daily life. Beginning with the pipeline safety management of construction, the article discusses the safety evaluation system, with the combination of considering relevant designs of project, engineering conditions and construction factors. It aims to provide a reliable methods and evidence for the safety evaluation of the pipeline project.

We study the creep properties of clastic soil in residual state. The intact samples are taken from a reactivated slow-moving landslide in the Three Gorges Reservoir Region, China. Firstly, the patterns of the landslide movement are analysed based on recent monitoring data, which indicate that the soil within the shear zone is undergoing two deformation processes: a creep phase, characterised by different creep rates, and a dormant phase. We then study the creep behaviour of the soil samples through a series of ring shear creep tests under various shear stress conditions. The creep response depends strongly on the ratio of the shear stress to the residual strength, and the normal effective stress, whereas the creep rate decreases due to strength regain. The long-term strength of the clastic soil is close to the residual strength. Therefore, the residual strength obtained from conventional shear test, which is less time consuming than creep test, can be used in long-term stability analyses of creeping landslides.