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BACKGROUND: Sexually transmitted infections (STIs) increase HIV infectivity through local inflammatory processes. Prevalent and incident STIs among people who live with HIV/AIDS (PLWHA) are indicators of high-risk sexual behaviors and imply potential spread of HIV. Little is known about the prevalence and incidence of concurrent syphilis and associated risk behaviors among PLWHA in China. METHODS: A retrospective cohort study was conducted among PLWHA who attended the outpatient clinic of a designated AIDS treatment hospital in Shenyang, China, between March 2009 and May 2013. Physical examinations and syphilis serology were conducted at each visit. A questionnaire on demographic characteristics was also collected. RESULTS: A total of 1010 PLWHA were enrolled, of whom 77.0% were men who have sex with men (MSM). The baseline syphilis prevalence among PLWHA was 19.8% (95% confidence interval [CI]:17.3-22.3%). During follow-up, 78.3% retained in the cohort, and contributed a median follow-up of 9.4 months (interquartile range: 5.9-18.7 months). Syphilis incidence among PLWHA was 18.7 (95% CI: 15.5-21.8) per 100 person years. Mulitvariate logistic analysis showed that receiving antiretroviral therapy (ART) (adjusted OR [aOR] = 0.48), older age (≥40 years vs. ≤24 years, aOR = 2.43), being MSM (aOR = 2.30) and having higher baseline HIV viral load (>100,000 copies/mL vs. ≤100,000 copies/mL, aOR = 1.56) were independent predictors for syphilis infection among PLWHA at enrollment (p < 0.05 for all). Mulivariate Cox regression found that receiving ART (adjusted hazard ratio [aHR] = 1.81), older age (≥40 years vs. ≤24 years, aHR: 5.17) and MSM status (aHR = 2.68) were independent risk factors for syphilis seroconversion (each p < 0.05). CONCLUSIONS: Syphilis prevalence and incidence were high among PLWHA in Shenyang. A campaign focusing on detection and treatment of syphilis among PLWHA is urgently needed, especially one with a focus on MSM who are at a higher risk for syphil

Optoelectronic devices based on layered materials such as graphene have resulted in significant interest due to their unique properties and potential technological applications. The electric and optoelectronic properties of nano GaTe flakes as layered materials are described in this article. The transistor fabricated from multilayer GaTe shows a p-type action with a hole mobility of about 0.2 cm^2 V^(-1) s^(-1). The gate transistor exhibits a high photoresponsivity of 104 A/W, which is greatly better than that of graphene, MoS_2, and other layered compounds. Meanwhile, the response speed of 6 ms is also very fast. Both the high photoresponsivity and the fast response time described in the present study strongly suggest that multilayer GaTe is a promising candidate for future optoelectronic and photosensitive device applications.

Background: Highly active antiretroviral therapy (HAART) has significantly decreased mortality among Chinese HIV patients. However, emerging HIV drug resistance (HIVDR) poses a growing threat to the long-term success and durability of HAART. Methods: Three cross-sectional surveys were conducted across the country from 2004 to 2006, respectively. Patients completed a questionnaire and provided blood for CD4 cell count, HIV viral load (VL), and HIV resistance genotyping. Factors associated with HIVDR were identified by logistic regression. Results: 3667 unique patients were included across the three surveys. Among 2826 treatment-experienced patients, median duration of treatment was 17.4 (IQR 8.6-28.4) months and HIVDR was identified in 543 (19.2%). Factors significantly associated with HIVDR included ART drug distribution location, CD4 cell count, initial HAART regimen, self-reported medication adherence, and province. Conclusions: Virologic failure increased over time on therapy but a significant proportion of patients in failure had no resistance mutations identified, suggesting that treatment adherence is suboptimal and must be emphasized. Due to the significantly higher risk of HIVDR in certain provinces, additional steps to reduce HIVDR should be taken. © 2013 Xing et al.

Aerospace Engineering

Liquid and solid precipitation is abundant in the high elevation, upper reach of the Heihe basin. The development of modern irrigation schemes in the middle reach of the basin is taking up an increasing share of fresh water resources, endangering the oasis and traditional irrigation systems in the lower reach. In this study, the response of vegetation in the Ejina Oasis in the lower reach of the Heihe River to the water yield of the upper catchment was analyzed by time series analysis of monthly observations of precipitation in the upper and lower catchment, river streamflow downstream of the modern irrigation schemes and satellite observations of vegetation index. Firstly, remote sensing data were used to monitor the vegetation dynamic for a long time period. Due to cloud-contamination, atmospheric influence and different solar angles, however, the quality and consistence of time series of remote sensing data is degraded. In this research we used a Fourier Transform method – the Harmonic Analysis of Time Series (HANTS) algorithm – to reconstruct cloud-free NDVI time series data from the Terra-MODIS dataset. Anomalies in precipitation, streamflow, and vegetation index are detected by comparing each year with the average year. The relationship between the anomalies in vegetation growth, the local precipitation and upstream water yield were analyzed. The same approach is used to identify, remove and gap-filling cloud contaminated observations in the satellite data for each year in the dataset. The results showed that: the previous year total runoff had a significant relationship with the vegetation growth in Ejina Oasis and that anomalies in monthly runoff of the Heihe River influenced the phenology of vegetation in the entire oasis during drier years. The time of maximum green-up was uniform throughout the oasis during wetter years, but showed a clear S–N gradient (downstream) during drier years., Remote Sensing, Aerospace Engineering

A supergraph containment search is to retrieve the data graphs contained by a query graph. In this paper, we study the problem of efficiently retrieving all data graphs approximately contained by a query graph, namely similarity search on supergraph containment. We propose a novel and efficient index to boost the efficiency of query processing. We have studied the query processing cost and propose two index construction strategies aimed at optimizing the performance of different types of data graphs: top-down strategy and bottom-up strategy. Moreover, a novel indexing technique is proposed by effectively merging the indexes of individual data graphs; this not only reduces the index size but also further reduces the query processing time. We conduct extensive experiments on real data sets to demonstrate the efficiency and the effectiveness of our techniques. © 2010 IEEE.

Substructure similarity search is to retrieve graphs that approximately contain a given query graph. It has many applications, e.g., detecting similar functions among chemical compounds. The problem is challenging as even testing subgraph containment between two graphs is NP-complete. Hence, existing techniques adopt the filtering-and-verification framework with the focus on developing effective and efficient techniques to remove non-promising graphs. Nevertheless, existing filtering techniques may be still unable to effectively remove many "low" quality candidates. To resolve this, in this paper we propose a novel indexing technique, GrafD-Index, to index graphs according to their "distances" to features. We characterize a tight condition under which the distance-based triangular inequality holds. We then develop lower and upper bounding techniques that exploit the GrafD-Index to (1) prune non-promising graphs and (2) include graphs whose similarities are guaranteed to exceed the given similarity threshold. Considering that the verification phase is not well studied and plays the dominant role in the whole process, we devise efficient algorithms to verify candidates. A comprehensive experiment using real datasets demonstrates that our proposed methods significantly outperform existing methods. © 2010 ACM.

The symposium volume includes a wide range of topics on process control in mining and metallurgical plants and are presented in sections: Expert system, control and performance monitoring (7 papers); Flotation (5 papers); Metallurgical processes, modelling (4 papers); Mining applications (3 papers); and Monitoring, analysis (4 papers). Papers on flotation are as follows: Towards the optimisation of flotation column operation, by Desbiens A., del Villar R., Maldonado M. and Bouchard J., p.99-120, 56 refs.; Model predictive control for flotation plants, by Lundh M., Gaulocher S., Pettersson J., Lindvall H. and Gallestey E., p.121-130, 6 refs.; Model predictive control of SAG mills and flotation circuits, by Forbes M.G. and Gough B., p.131-142, 4 refs.; Online measurement of xanthate in flotation circuits by means of UV spectrophotometry, by Lalla B., Knights B.D.H. and Steenkamp C.J.H., p.143-153, 9 refs.; and Improved flow and flotation monitoring for process efficiency improvements through new technology utilising non-invasive passive arrays, by O'Keefe C.V., Maron R. and Rothman P., p.155-166. Other papers with more general scope include: Best practices for managing control loop performance - roadmap to success, by McNabb C. and Ruel M., p.3-9, 3 refs.; AHEAD (Asset Health Effectiveness and Diagnostics) - a toolkit for intelligent asset performance monitoring, by Narozny J., Wood M., Power Y. and Festa A., p.83-95, 8 refs.; Modelling in metallurgical process development, by Kandep R. and Grovlen A., p.169-175, 1 ref.; High-fidelity dynamic simulation for the mining and metallurgical industry, by Delisle M. and Alamo J., p.199-209, 4 refs.; Remote operation and collaboration in mining applications, by Murray J., Daugherty D. and Smith A., p.225-231, 3 refs.; Long-term sustainability of advanced process control optimisation projects, by Sheehan C.P.L., Chmelyk T., Waite A. and Corovic D., p.233-241; Improving accuracy, transparency and auditability by moving from spr, 2 ind., The symposium volume includes a wide range of topics on process control in mining and metallurgical plants and are presented in sections: Expert system, control and performance monitoring (7 papers); Flotation (5 papers); Metallurgical processes, modelling (4 papers); Mining applications (3 papers); and Monitoring, analysis (4 papers). Papers on flotation are as follows: Towards the optimisation of flotation column operation, by Desbiens A., del Villar R., Maldonado M. and Bouchard J., p.99-120, 56 refs.; Model predictive control for flotation plants, by Lundh M., Gaulocher S., Pettersson J., Lindvall H. and Gallestey E., p.121-130, 6 refs.; Model predictive control of SAG mills and flotation circuits, by Forbes M.G. and Gough B., p.131-142, 4 refs.; Online measurement of xanthate in flotation circuits by means of UV spectrophotometry, by Lalla B., Knights B.D.H. and Steenkamp C.J.H., p.143-153, 9 refs.; and Improved flow and flotation monitoring for process efficiency improvements through new technology utilising non-invasive passive arrays, by O'Keefe C.V., Maron R. and Rothman P., p.155-166. Other papers with more general scope include: Best practices for managing control loop performance - roadmap to success, by McNabb C. and Ruel M., p.3-9, 3 refs.; AHEAD (Asset Health Effectiveness and Diagnostics) - a toolkit for intelligent asset performance monitoring, by Narozny J., Wood M., Power Y. and Festa A., p.83-95, 8 refs.; Modelling in metallurgical process development, by Kandep R. and Grovlen A., p.169-175, 1 ref.; High-fidelity dynamic simulation for the mining and metallurgical industry, by Delisle M. and Alamo J., p.199-209, 4 refs.; Remote operation and collaboration in mining applications, by Murray J., Daugherty D. and Smith A., p.225-231, 3 refs.; Long-term sustainability of advanced process control optimisation projects, by Sheehan C.P.L., Chmelyk T., Waite A. and Corovic D., p.233-241; Improving accuracy, transparency and auditability by moving from spr

The extractable energy value from all sources of heat energy generated underground during the active life of a deep mine is discussed, with particular reference to the recovery of energy from mine waters. Three principal routes by which to consider utilisation of latent energy contained within mine water are reviewed comprising direct extraction; increasing heat content by boosting the temperature further to generate steam and electricity; and indirect extraction as a support medium for developing precursors for alternate energy sources such as the growth of microalgae in on-site lagoons and tailing ponds for producing biodiesel., The extractable energy value from all sources of heat energy generated underground during the active life of a deep mine is discussed, with particular reference to the recovery of energy from mine waters. Three principal routes by which to consider utilisation of latent energy contained within mine water are reviewed comprising direct extraction; increasing heat content by boosting the temperature further to generate steam and electricity; and indirect extraction as a support medium for developing precursors for alternate energy sources such as the growth of microalgae in on-site lagoons and tailing ponds for producing biodiesel.

Dynamic models for an industrial nickel smelter off-gas system, tackling hazardous sulphur dioxide, carbon monoxide and carbon dioxide, are described. The models were developed using mass continuity, the first law of thermodynamics, the ideal gas state equation and momentum conservation laws, using five approximating assumptions. Dynamic modelling equations were developed for the units in the furnace and converter off-gas system whilst taking into account various variables such as the louvre in the furnace off-gas, the fans and blowers and the electrostatic precipitator gas pressure. SO2 leakage to the atmosphere is prevented by controlling the gas pressure to have negative values in the roaster off-gas system. The fan and blower were found to change the gas pressure effectively and quickly but the effects of the manipulated input variables were significantly reduced by the leakage area. Air in-leakage, controlled by a louvre, is intentionally introduced in the furnace off-gas system to cool down the off-gas temperature. Simulation results show that increasing louvre opening has the effect of reducing the louvre gas temperature but has the opposite effect on the freeboard temperature and pressure. Water and air are introduced in the roaster and furnace off-gas systems for cooling the off-gas and comparison of these in terms of operational energy efficiency may be beneficial., Dynamic models for an industrial nickel smelter off-gas system, tackling hazardous sulphur dioxide, carbon monoxide and carbon dioxide, are described. The models were developed using mass continuity, the first law of thermodynamics, the ideal gas state equation and momentum conservation laws, using five approximating assumptions. Dynamic modelling equations were developed for the units in the furnace and converter off-gas system whilst taking into account various variables such as the louvre in the furnace off-gas, the fans and blowers and the electrostatic precipitator gas pressure. SO2 leakage to the atmosphere is prevented by controlling the gas pressure to have negative values in the roaster off-gas system. The fan and blower were found to change the gas pressure effectively and quickly but the effects of the manipulated input variables were significantly reduced by the leakage area. Air in-leakage, controlled by a louvre, is intentionally introduced in the furnace off-gas system to cool down the off-gas temperature. Simulation results show that increasing louvre opening has the effect of reducing the louvre gas temperature but has the opposite effect on the freeboard temperature and pressure. Water and air are introduced in the roaster and furnace off-gas systems for cooling the off-gas and comparison of these in terms of operational energy efficiency may be beneficial.

We present a set of compelling science cases for the ALMA Band 1 receiver suite. For these cases, we assume in tandem the updated nominal Band 1 frequency range of 35-50 GHz with a likely extension up to 52 GHz; together these frequencies optimize the Band 1 science return. The scope of the science cases ranges from nearby stars to the re-ionization edge of the Universe. Two cases provide additional leverage on the present ALMA Level One Science Goals and are seen as particularly powerful motivations for building the Band 1 Receiver suite: (1) detailing the evolution of grains in protoplanetary disks, as a complement to the gas kinematics, requires continuum observations out to ~35 GHz (~9mm); and (2) detecting CO 3-2 line emission from galaxies like the Milky Way during the epoch of re-ionization, i.e., 6 < z < 10, also requires Band 1 receiver coverage. The range of Band 1 science is wide, however, and includes studies of very small dust grains in the ISM, pulsar wind nebulae, radio supernovae, X-ray binaries, the Galactic Center (i.e., Sgr A*), dense cloud cores, complex carbon-chain molecules, masers, magnetic fields in the dense ISM, jets and outflows from young stars, distant galaxies, and galaxy clusters (i.e., the Sunyaev-Zel'dovich Effect). A comparison of ALMA and the Jansky VLA (JVLA) at the same frequencies of Band 1 finds similar sensitivity performance at 40-50 GHz, with a slight edge for ALMA at higher frequencies (e.g., within a factor of 2 for continuum observations). With its larger number of instantaneous baselines, however, ALMA Band 1data will have greater fidelity than those from the JVLA at similar frequencies., Comment: 62 pages, 16 figures

Graphs are widely used to model complicated data semantics in many applications. In this paper, we aim to develop efficient techniques to retrieve graphs, containing a given query graph, from a large set of graphs. Considering the problem of testing subgraph isomorphism is generally NP-hard, most of the existing techniques are based on the framework of filtering-and-verification to reduce the precise computation costs; consequently various novel feature-based indexes have been developed. While the existing techniques work well for small query graphs, the verification phase becomes a bottleneck when the query graph size increases. Motivated by this, in the paper we firstly propose a novel and efficient algorithm for testing subgraph isomorphism, QuickSI. Secondly, we develop a new feature-based index technique to accommodate QuickSI in the filtering phase. Our extensive experiments on real and synthetic data demonstrate the efficiency and scalability of the proposed techniques, which significantly improve the existing techniques. © 2008 VLDB Endowment.