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Guangxi, a province in southwestern China, has the second highest reported number of HIV/AIDS cases in China. This study aimed to develop an accurate and effective model to describe the tendency of HIV and to predict its incidence in Guangxi. HIV incidence data of Guangxi from 2005 to 2016 were obtained from the database of the Chinese Center for Disease Control and Prevention. Long short-term memory (LSTM) neural network models, autoregressive integrated moving average (ARIMA) models, generalised regression neural network (GRNN) models and exponential smoothing (ES) were used to fit the incidence data. Data from 2015 and 2016 were used to validate the most suitable models. The model performances were evaluated by evaluating metrics, including mean square error (MSE), root mean square error, mean absolute error and mean absolute percentage error. The LSTM model had the lowest MSE when the N value (time step) was 12. The most appropriate ARIMA models for incidence in 2015 and 2016 were ARIMA (1, 1, 2) (0, 1, 2)12 and ARIMA (2, 1, 0) (1, 1, 2)12, respectively. The accuracy of GRNN and ES models in forecasting HIV incidence in Guangxi was relatively poor. Four performance metrics of the LSTM model were all lower than the ARIMA, GRNN and ES models. The LSTM model was more effective than other time-series models and is important for the monitoring and control of local HIV epidemics.
There has been a lack of prevalence estimates of DSM-5 mental disorders in child populations at the national level worldwide. This study estimated the lifetime and 6-month prevalence of mental disorders according to the DSM-5 diagnostic criteria in Taiwanese children.
Taiwan's National Epidemiological Study of Child Mental Disorders used the stratified cluster sampling to select 69 schools in Taiwan resulting in a nationally representative sample of 4816 children in grades 3 (n = 1352), 5 (n = 1297) and 7 (n = 2167). All the participants underwent face-to-face psychiatric interviews using the Kiddie-Schedule for Affective Disorders and Schizophrenia-Epidemiological version, modified for the DSM-5, and they and their parents completed questionnaires. The inverse probability censoring weighting (IPCW)-adjusted prevalence was reported to minimise non-response bias.
The IPCW-adjusted prevalence rates of mental disorders decreased by 0.1–0.5% than raw weighted prevalence. The IPCW-adjusted weighted lifetime and 6-month prevalence rates for overall mental disorders were 31.6 and 25.0%, respectively. The most prevalent mental disorders (lifetime, 6-month) were anxiety disorders (15.2, 12.0%) and attention-deficit hyperactivity disorder (10.1, 8.7%), followed by sleep disorders, tic disorders, oppositional defiant disorder and autism spectrum disorder. The prevalence rates of new DSM-5 mental disorders, avoidant/restrictive food intake disorder and disruptive mood dysregulation disorder were low (<1%).
Our findings, similar to the DSM-IV prevalence rates reported in Western countries, indicate that DSM-5 mental disorders are common in the Taiwanese child population and suggest the need for public awareness, early detection and prevention.
Climatic change that affects biological productivity is often argued to be a primary force influencing human activities during the glacial period. To test this assumption, we combine in-site pollen, paleoclimatic, and archaeological data from the Dadiwan site and nearby areas on the western Loess Plateau (WLP) that date to Marine Oxygen Isotope Stage (MIS) 3. Our comparison of multiple datasets suggests that regional human activities increased when the vegetation around the Dadiwan area shifted from forest steppe in the early MIS 3 (59–46.7 ka) to steppe in the middle to late MIS 3 (46.7–29.5 ka). Our results indicate that regional human activities increased again during the late MIS 3 when the amount of precipitation was higher, as indicated by the lower Artemisia proportion. We suggest that increased precipitation on the WLP enhanced the above-ground biomass production and may be responsible for an increase in human activity and population in this region.
This study investigates numerically the performance of applying aerospike nozzle in a hydrogen peroxide mono-propellant propulsion system. A set of governing equations, including continuity, momentum, energy and species conservation equations with extended k-ε turbulence equations, are solved using the finite-volume method. The hydrogen peroxide mono-propellant is assumed to be fully decomposed into water vapor and oxygen after flowing through a catalyst bed before entering the nozzle. The aerospike nozzle is expected to have high performance even in deep throttling cases due to its self-compensating characteristics in a wide range of ambient pressure environments. The results show that the thrust coefficient efficiency (Cf,η) of this work exceeds 90% of the theoretical value with a nozzle pressure ratio (PR) in the range of 20 ~ 45. Many complex gas dynamics phenomena in the aerospike nozzle are found and explained in the paper. In addition, performance of the aerospike nozzle is compared with that of the bell-shape nozzle.
A compact hybrid rocket motor design that incorporates a dual-vortical-flow (DVF) concept is proposed. The oxidizer (nitrous oxide, N2O) is injected circumferentially into various sections of the rocket motor, which are sectored by several solid fuel “rings” (made of hydroxyl-terminated polybutadiene, HTPB) that are installed along the central axis of the motor. The proposed configuration not only increases the residence time of the oxidizer flow, it also implies an inherent “roll control” capability of the motor. Based on a DVF motor geometry with a designed thrust level of 11.6 kN, the characteristics of the turbulent reacting flow within the motor and its rocket performance were analyzed with a comprehensive numerical model that implements both real-fluid properties and finite-rate chemistry. Data indicate that the vacuum specific impulse (Isp) of the DVF motor could reach 278 s. The result from a preliminary ground test of a lab-scale DVF hybrid rocket motor (with a designed thrust level of 3,000 N) also shows promising performance. The proposed DVF concept is expected to partly resolve the issue of scalability, which remains challenging for hybrid rocket motors development.
GJB2 gene mutations are highly prevalent in pre-lingual hearing loss patients from China. Pre-lingual deafness is a sensorineural disorder that can only be treated with cochlear implantation.
The prevalence of GJB2 gene mutations was examined in 330 randomly selected patients treated with cochlear implantation.
Overall, 276 patients (83.64 per cent) carried variations in the GJB2 gene. Seventeen different genotypes were identified, including 10 confirmed pathogenic mutations (c.235delC, c.299delAT, c.176del16, p.E47X, p.T123N, p.V167M, p.C218Y, p.T86R, p.V63L and p.R184Q), 3 polymorphisms (p.V27I, p.E114 G and p.I203 T) and 2 unidentified mutations (p.V37I and c.571 T > C).
A total of 103 patients (31.2 per cent) carried 2 confirmed pathogenic mutations. The frequency of c.235delC was higher than that reported previously in the Jiangsu province. The two novel mutations identified, 69C > G and 501G > A, are likely to be polymorphisms.
Peripheral blood viral load is an important indicator of viral production and clearance. Previous studies have suggested that viral load might predict the rate of decrease in CD4+ cell count and progression to AIDS and death. Here, we conducted a retrospective analysis of the trends in HIV-1 viral load in southeast China. Among inpatients newly diagnosed with HIV infection, we found that viral load has increased over the past decade from 4·20 log10 copies/ml in 2002 to 6·61 log10 copies/ml in 2014, with a mean increase of 0·19 log10 copies/ml each year. However, the CD4+ cell count was stable and insensitive to changes in viral load. Thus, increasing viral load appears to be an emerging trend in newly diagnosed HIV-infected inpatients.
The interferon-inducible transmembrane protein 3 (IFITM3), as one of the key genes involved in the interferon pathway, is critical for defending the host against influenza virus, and the rs12252 T>C variant in IFITM3 might be associated with susceptibility to severe influenza. Owing to contradictory and inconclusive results, we performed a meta-analysis to assess the association between rs12252 T>C polymorphism and severe influenza risk. A comprehensive literature search up to 1 August 2014 was conducted in EMBASE, Pubmed, Web of Science, VIP, Wanfang and CNKI databases. Four eligible studies with a total of 445 influenza patients and 3396 controls were included in this meta-analysis. Overall, our results demonstrated a significant association between the IFITM3 rs12252 T>C polymorphism and influenza risk [C vs. T: odds ratio (OR) 1·68, 95% confidence interval (CI) 1·32–2·13; CC vs. CT+TT: OR 2·38, 95% CI 1·52–3·73; CC+CT vs. TT: OR 1·62, 95% CI 1·18–2·22]. Stratification by ethnicity indicated that the variant C allele was associated with an 88% increased risk of influenza in Asians (C vs. T: OR 1·88, 95% CI 1·34–2·62). Moreover, subjects carrying the variant C allele had an increased risk of developing severe illness upon influenza infection (C vs. T: OR 2·70, 95% CI 1·86–3·94). However, no significant association was observed in patients with mild infection (C vs. T: OR 1·26, 95% CI 0·93–1·71). Our meta-analysis suggests that IFITM3 rs12252 T>C polymorphism is significantly associated with increased risk of severe influenza but not with the chance of initial virus infection.
This is the first report of microsatellite markers (simple sequence repeats, SSR) for fall webworm, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae), an important quarantine pest in some European and Asian countries. Here, we developed 48 microsatellite markers for H. cunea from SSR enrichment libraries. Sequences isolated from libraries were sorted into four categories and analyzed. Our results suggest that sequences classified as Grouped should not be used for microsatellite primer design. The genetic diversity of microsatellite loci was assessed in 72 individuals from three populations. The number of alleles per locus ranged from 2 to 5 with an average of 3. The observed and expected heterozygosities of loci ranged from 0 to 0.958 and 0 to 0.773, respectively. A total of 18 out of 153 locus/population combinations deviated significantly from Hardy–Weinberg equilibrium. Moreover, significant linkage disequilibrium was detected in one pair of loci (1275 pairs in total). In the neutral test, two loci were grouped into the candidate category for positive selection and the remainder into the neutral category. In addition, a complex mutation pattern was observed for these loci, and FST performed better than did RST for the estimation of population differentiation in different mutation patterns. The results of the present study can be used for population genetic studies of H. cunea.
The Critically Endangered Chinese giant salamander Andrias davidianus, the world's largest amphibian, is severely threatened by unsustainable exploitation of wild individuals. However, field data with which to assess the salamander's status, population trends, or exploitation across its geographical range are limited, and recent field surveys using standard ecological field techniques have typically failed to detect wild individuals. We conducted community-based fieldwork in three national nature reserves (Fanjingshan, Leigongshan and Mayanghe) in Guizhou Province, China, to assess whether local ecological knowledge constitutes a useful tool for salamander conservation. We collected a sample of dated salamander sighting records and associated data from these reserves for comparative assessment of the relative status of salamander populations across the region. Although Fanjingshan and Leigongshan are still priority sites for salamander conservation, few recent sightings were recorded in either reserve, and respondents considered that salamanders had declined locally at both reserves. The species may already be functionally extinct at Mayanghe. Although respondent data on threats to salamanders in Guizhou are more difficult to interpret, overharvesting was the most commonly suggested explanation for salamander declines, and it is likely that the growing salamander farming industry is the primary driver of salamander extraction from Guizhou's reserves. Questionnaire-based surveys can collect novel quantitative data that provide unique insights into the local status of salamander populations, and we advocate wide-scale incorporation of this research approach into future salamander field programmes.
We have investigated the photon-energy dependence of nonlinear optical absorption in graphene in the near infrared (NIR) and visible range (1.13 – 3.1 eV). Two nonlinear processes, namely one-photon interband absorption saturation and two-photon absorption (2PA), have been unambiguously determined in high-quality, CVD-grown, multilayer graphene films with using femtosecond Z-scan technique. The absorption saturation is found to have a square dependence on the photon energy. The 2PA spectrum is measured to be close to the theoretical prediction of ω-4 dependence at NIR wavelengths. In the visible range, however, the photon-energy dependence of 2PA is dominated by the excitonic Fano resonance.
Traditional electron microscopy techniques such as bright-field imaging provide poor contrast for organic films and identification of structures in amorphous material can be problematic, particularly in high-performance organic solar cells. By combining energy-filtered corrected transmission electron microscopy, together with electron energy loss and X-ray energy-dispersive hyperspectral imaging, we have imaged PTB7/PC61BM blended polymer optical photovoltaic films, and were able to identify domains ranging in size from several hundred nanometers to several nanometers in extent. This work verifies that microstructural domains exist in bulk heterojunctions in PTB7/PC61BM polymeric solar cells at multiple length scales and expands our understanding of optimal device performance providing insight for the design of even higher performance cells.
In this paper, a novel set of macros with line/space width from 128nm/128nm, 64nm/64nm to 32nm/32nm was designed and installed on 20nm technology-node hardware. The pitch-dependent pad erosion post Cu CMP was studied by atomic-force microscopy (AFM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) quantitatively on these macros. Two methods were investigated to reduce the difference between pitch- and density-induced CMP non-uniformity. The first is using new scheme of partial Cu plating process followed by SiCNH insulator deposition and then CMP. The second is through the selection of slurries and pads. Both results are discussed in this paper.