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The heteroepitaxial growth of vertically aligned gallium nitride (GaN) single-crystalline microrod arrays on silicon substrates was achieved with high reproducibility by using the plasma-enhanced chemical vapor deposition (PECVD) method in the furnace. By reducing the plasma power from 70 to 15 W, the crystal morphology of GaN varied from thin films to microrod arrays with the decreased V/III gas ratio. The growth of GaN crystals occurred in the vertical direction of the substrate and in the lateral direction of the growth axis via the self-catalytic vapor-liquid-solid mechanism (VLS mechanism) and the vapor-solid mechanism (VS mechanism), respectively, contributing to the formation of inverted hexagonal GaN cone microrods. Furthermore, the morphology of inverted hexagonal GaN cone microrods shows extremely small contact areas between the microrods and the substrate, suggesting the potential to solve the problems of stress accumulation and poor crystalline qualities of heteroepitaxy. With the raised growth temperature of GaN from 930 to 980 °C, the material quality was improved and the high crystalline qualities were obtained, owing to the successful surface migration of gallium atoms. However, the density of GaN microrods became lower with the increased growth temperature because the spatial temperature gradient was reduced and the evaporation of gallium was enhanced, leading to fewer gallium atoms precipitating and remaining on the substrate. The growth direction of vertically aligned GaN single-crystalline microrod arrays with the (002) crystal plane is along the [0001] orientation ( c axis) and normal to the substrate surface, which may bring about many device applications in future studies., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Objective: To understand the prevalence of Neisseria gonorrhoeae (NG) infection and related factors in outpatients of sexually transmitted disease (STD) in Shenzhen and provide scientific evidence for targeted intervention. Methods: A cross-sectional study was conducted in STD outpatients who were aged 18-49 years, had had sexual intercourse, had not received antibiotics in the last 2 weeks and sought medical cares in 22 medical institutions in 6 districts of Shenzhen from 15 April, 2018 to 16 May, 2018, their basic information and urine samples were collected, and NG in urine sample was detected by nucleic acid amplification test. Logistic regression analysis was conducted to identify the related factors for NG infection. Results: The information collection and sample collection were completed for 8 324 STD outpatients, among these STD outpatients, 196 were NG positive, with a positive rate of 2.4% (196/8 324). The positive rate of NG in men (5.8%, 148/2 567) was higher than that in women (0.8%, 47/5 742) ( χ (2)=189.43, P <0.05). Aged 24 years or below ( OR =2.11, 95% CI : 1.44-3.09), single/divorced/widowed ( OR =1.98, 95% CI :1.38-2.84), having casual sex in the last 3 months ( OR =1.77, 95% CI :1.29-2.43) were the related factors for NG infection. Conclusions: We found that NG infection rate was high in STD outpatients in Shenzhen. The infection rates in men and in women differed obviously. It is necessary to conduct gonorrhea screening and intervention in STD outpatients with high-risk behaviors, such as extramarital and casual sex behaviors, and standardize the treatment to reduce the incidence and spread of gonorrhea and other STDs.

Chlamydia trachomatis (CT) infection has been a major public health threat globally. Monitoring and prediction of CT epidemic status and trends are important for programme planning, allocating resources and assessing impact; however, such activities are limited in China. In this study, we aimed to apply a seasonal autoregressive integrated moving average (SARIMA) model to predict the incidence of CT infection in Shenzhen city, China. The monthly incidence of CT between January 2008 and June 2019 in Shenzhen was used to fit and validate the SARIMA model. A seasonal fluctuation and a slightly increasing pattern of a long-term trend were revealed in the time series of CT incidence. The monthly CT incidence ranged from 4.80/100 000 to 21.56/100 000. The mean absolute percentage error value of the optimal model was 8.08%. The SARIMA model could be applied to effectively predict the short-term CT incidence in Shenzhen and provide support for the development of interventions for disease control and prevention.

The aim of this study is to assess the HIV/syphilis epidemic among men who have sex with men (MSM) aged <50 years and ≥50 years in Shenzhen, and explore the associated factors of HIV/syphilis co-infections among MSM in Shenzhen, in order to help prevention and intervention programs determine their target sub-group. A serial cross-sectional study was conducted on MSM in Shenzhen city, China from 2009 to 2017. A questionnaire was used to collect demographic characteristics, history of HIV testing, history of blood donation and sexual behaviors. 5 ml of venous blood were collected for syphilis and HIV tests. The overall prevalence of HIV, syphilis, HIV/syphilis co-infection was 9.40%, 18.97%, and 4.91%, respectively. The prevalence of HIV (15.26%), syphilis (27.71%), HIV/syphilis co-infection (9.24%) in aged ≥50 years MSM was significantly higher than aged <50 years MSM (9.15%, 18.59% and 4.72%, respectively). The following factors were found to be significantly associated with HIV/syphilis co-infections (P<0.05): age≥50 years (OR = 1.78, 95% CI = 1.10-2.87), high school or lower (OR = 1.49, 95% CI = 1.10-2.01), monthly income ≤436.2 USD (OR = 1.74, 95% CI = 1.25-2.42), monthly income 436.4-727.2 USD (OR = 1.46, 95% CI = 1.05-2.03), ≥2 anal sex partners in the past 6 months (OR = 1.59, 95% CI = 1.02-2.49), ≥2 oral sex partners in the past 6 months (OR = 1.60, 95% CI = 1.08-2.36), inconsistent condom use during anal sex in the past 6 months (OR = 1.50, 95% CI = 1.11-2.03). We found that aged <50 years and ≥50 years MSM in Shenzhen had a high prevalence of HIV/syphilis infection in a period from 2009 to 2017. Age-specific sexually transmitted diseases education, prevention, and intervention programs for aged ≥50 years MSM should be implemented urgently and integrated interventions of both HIV and syphilis infections on MSM are needed in the future., Competing Interests: The authors have declared that no competing interests exist.

[This corrects the article DOI: 10.1371/journal.pone.0196516.].

Aim: Engagement by medical professionals with social media (SM) is increasing. Variation is noted in engagement between SM platforms and between surgical specialities and geographical regions. We aimed to study SM engagement by colorectal surgeons attending an international conference., Method: Surgeons were identified from the delegate list of the 2017 Annual Meeting of the American Society of Colon and Rectal Surgeons (ASCRS) and Tripartite Meeting (Seattle, Washington, USA). Delegates were searched on Twitter and LinkedIn for the presence of a matching profile. SM presence, activity, gender and geographical region were analysed., Results: Two hundred and seventy (13.2%) surgeons had Twitter accounts and 994 (44.3%) had LinkedIn profiles. UK surgeons were more likely to be on Twitter than surgeons from elsewhere (23.4% vs 12.7%, P = 0.0072). Significant variation in SM membership between each geographical region was noted, with usage rates for Twitter of 18.1% in Europe, 14.4% in North America, 12.9% in South America, 4.3% in Oceania, 3.7% in Asia and 0% in Africa. A similar picture for LinkedIn is seen. The #ASCRS17 meeting saw the highest participation of users to date (979 participants, over 7000 individual tweets and nearly 14 million impressions)., Conclusion: SM engagement by colorectal surgeons continues to increase. Significant geographical variation is noted, suggesting that SM's unique potential for education and networking may not yet be widely appreciated globally. Future work should include further analysis into tweet contents to gain insights and optimize the use of SM as an educational adjunct., (Colorectal Disease © 2018 The Association of Coloproctology of Great Britain and Ireland.)

This study was aimed to estimate the prevalences of chlamydia (CT) and gonococcal (NG) infections and explore risk factors associated with the CT infection among women in Shenzhen, China. We collected socio-demographic and clinical data from women (aged 20-60) and determined positivity of CT or NG by nucleic acid amplification test (NAAT) with self-collected urine specimens. We estimated prevalence of CT and NG and determined risk factors associated with CT infection. Among 9,207 participants, 4.12% (95% confidence interval [CI], 3.71%-4.53%) tested positive for CT and 0.17% (95% CIs, 0.09%-0.25%) for NG. Factors significantly associated with CT infection included being an ethnic minority (ethnicity other than Han China) (Adjusted odds ratio [AOR], 1.9; 95% CI, 1.2-3.0), using methods other than condom for contraception (AOR, 1.5; 95% CI, 1.2-1.8), having a history of adverse pregnancy outcomes (AOR, 1.4; 95% CI, 1.1-1.8), and experiencing reproductive tract symptoms in the past three months (AOR, 1.3; 95% CI, 1.0-1.7). we found that CT infection is prevalent among women in Shenzhen, China and associated with both demographic and behavioral factors. A comprehensive CT screening, surveillance and treatment programme targeting this population is warranted.

Objective: To investigate the factors associated with syphilis/HIV infection among men who have sex with men (MSM) maintaining a single sexual partner in Shenzhen. Methods: Respondent driven sampling and snowball sampling method were used to recruit MSM receiving voluntary counseling and testing in Shenzhen Rainbow clinic from 2011 to 2016., Inclusion Criteria: aged 18 years and above; reported having one or more anal sexual partners in the recent 6 months. A total of 3 109 men who have sex with men (MSM) were involved in the study. Questionnaire-based interviews were conducted on a one-on-one basis. Data were collected including socio-demographic information, human immunodeficiency virus (HIV) testing history, history of blood donation and drug abuse in the recent two years, self-identified sexual orientation, role in homosexual behavior, ever being money boys (MB) and clients of MB, female sexual partners in the recent 6 months. 5 ml blood samples were taken after questionnaires. Syphilis was screened using toluidine red unheated serum test for the antibody of treponema pallidum and then confirmed by treponema pallidum particle assay. The enzyme-linked immunosorbent assay (ELISA) was used for screening HIV and western blot was used to confirm the HIV screening results. The difference of condom use among MSM between female sexual partners and male sexual partners were compared. Multivariate unconditional stepwise logistic regression model was used to analyze factors associated with syphilis infection and HIV positive among MSM. Results: A total of 3 109 eligible participants with mean (SD) age of 31.49 (8.64) years were enrolled in this study. Among them, 565 cases were infected with syphilis (18.17%), 330 cases were infected with HIV (10.61%), and 165 cases (5.31%) were syphilis co-infected with HIV. 791 (25.44%) reported maintaining a single sexual partners in the recent 6 months. Compared to MSM with multiple sexual partners, the prevalence of syphilis and HIV infection among MSM with a single sexual partner were lower, and the OR (95% CI ) were 0.64 (0.51-0.81) and 0.66 (0.49-0.90), respectively. Conclusion: The proportion of fixed single sexual partner was much lower among MSM in Shenzhen. Maintaining a single sexual partners can reduce the risk of syphilis/HIV infection among MSM.

Background: Early screening for syphilis among pregnant women and the effective treatment of maternal syphilis is fundamental to prevent congenital syphilis (CS)., Methods: We obtained data from the Shenzhen Program for Prevention of CS (SPPCS) and estimated incidence rates of CS among infants born to syphilis-seropositive women treated with different regimens or untreated for maternal syphilis., Results: A total of 4746 matched cases of syphilis-seropositive mothers and their infants were included for analyses, and 162 infants were diagnosed with CS, providing an overall incidence of 3.41% (95% confidence interval [CI], 2.91%-3.98%). Among infants born to syphilis-seropositive women who had syphilis and were adequately treated before pregnancy, the incidence was 0.22% (95% CI, .05%-.66%). There were 159 cases of CS occurring in 3519 infants born to women who were syphilis-seropositive during their pregnancies, for an incidence of 4.52% (95% CI, 3.84%-5.28%). The incidence of CS was 1.82%-11.90% lower among infants born to the women treated with early benzathine penicillin G (BPG) compared with those treated with late BPG (adjusted odds ratio [aOR], 8.06 [95% CI, 2.93-22.21]; P < .001), other antibiotics (aOR, 7.71 [95% CI, .86-69.28]; P = .068), or those untreated (aOR, 68.28 [95% CI, 29.64-157.28]; P < .001). The incidence rates were 0.22% (95% CI, .06%-.80%) and 0.59% (95% CI, .35%-1.02%) in infants born to women treated with 2 courses and 1 course of BPG, respectively, corresponding to a risk difference of 0.37% (aOR, 1.74; 95% CI, .37-8.26)., Conclusions: Treatment of syphilis-seropositive pregnant women with 1 course of intramuscular BPG before 28 gestational weeks is critical for prevention of CS., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Objective: To investigate the status and factors associated with commercial sexual behavior among men who have sex with men (MSM) in Shenzhen. Methods: A convenience sampling method was used to recruit MSM in Shenzhen from 2011 to 2015. Questionnaire-based interviews were conducted on a one-on-one basis. Data were collected, including socio-demographic information, HIV testing history, history of blood donation and drug abuse in the last 2 years, self-reported sexual orientation, role in homosexual behavior, and experience serving as a male sex worker and/or as a client of male sex workers. Blood samples (5 ml) were taken and tested for treponema pallidum and HIV antibodies. The rate of MSM serving as male sex workers among different age groups was analyzed using the Cochran-Armitage trend test. Factors associated with commercial sexual behavior were analyzed by univariate logistic regression and multivariate unconditional logistic regression. Results: Among the 3 040 MSM recruited, 341 (11.2%) reported having served as male sex worker. The prevalence rates of syphilis, HIV, and syphilis-HIV co-infection among all recruited MSM were 18.3% (556/3 040), 9.8% (297/3 040), and 5.1% (154/3 040), respectively. The prevalence rates of syphilis, HIV, and syphilis-HIV co-infection among those who served as male sex worker were 27.0% (92/341), 16.4% (56/341), and 8.8% (30/341), respectively, and the prevalence rates among MSM with no experience as male sex worker were 17.2% (464/2 699), 8.9% (241/2 699), and 4.6% (124/2 699), respectively. Compared with non-male sex worker MSM, male sex worker had a significantly higher prevalence rates of syphilis, HIV, and syphilis-HIV co-infection (with χ 2 values of 19.41, 19.28, and 11.12, and P -values of <0.001,<0.001, 0.001, respectively). The results of the multivariate logistic regression analysis indicate tha t> 30-year-old MSM or education level of college or above, reside in Shenzhen for 0.5-3.0 years or the living years above 3.0 years are less likely to serve as male sex worker compared with<30-year-old MSM, education level of high school or below, who reside in Shenzhen for less than 0.5 years; the OR (95% CI ) values were 0.55 (0.42-0.71), 0.10 (0.06-0.14), 0.46 (0.31-0.68), and 0.23 (0.16-0.33), respectively. MSM having a monthly income of >5 000 yuan, drug abuse history, experience as male sex worker clients, and self-reported insertive and receptive anal sex behaviors were more likely to have experience serving as male sex worker compared with those having a monthly income of <3 000 yuan ( OR= 2.57, 95% CI: 1.85-3.57), no drug abuse history ( OR= 3.23, 95% CI: 2.14-4.87), no experience as male sex worker clients ( OR =1.50, 95% CI: 1.04-2.15) and who engage in predominantly insertive anal sex behaviors ( OR= 1.77, 95% CI: 1.34-2.35). Conclusion: Age, education level, duration of residence in Shenzhen, monthly income, history of drug abuse, role in homosexual activity, and had experience commercial sex activity were associated with serving as a male sex worker among MSM. These factors need to be considered when designing syphilis/HIV prevention programs for MSM.

The purpose of this investigation was to assess the effectiveness of an intervention program on mother-to-child transmission (MTCT) of syphilis and investigate determinants of congenital syphilis (CS) and adverse pregnancy outcomes (APOs). The Shenzhen local government initiated an intervention program of MTCT of syphilis in 2001. Based on this program, maternal and paternal factors associated with CS and APOs among syphilitic women were investigated from 2007 to 2012 by a prospective cohort study. From 2002 to 2012, 2,441,237 pregnant women were screened and screening coverage reached 97.2 % in 2012. In the background of continuing growth of CS in China, CS in Shenzhen significantly decreased from 109.3 cases in 2002 to 9.9 cases in 2012 per 100,000 live births. Maternal education (adjusted odds ratio [aOR]CS = 0.65; aORAPOs = 0.79) and history of syphilis (aORCS = 0.28; aORAPOs = 0.61), as well as paternal age (aORCS = 0.62; aORAPOs = 0.86) and education (aORCS = 0.66; aORAPOs = 0.86) were negatively associated with CS and APOs, but maternal unmarried status (aORCS = 1.95; aORAPOs = 2.61), inadequate antenatal care (ANC) (aORCS = 3.61; aORAPOs = 1.79), more sexual partners (aORCS = 1.51; aORAPOs = 1.39), every week of delay in treatment (aORCS = 2.82; aORAPOs = 1.27), higher baseline titers of nontreponemal antibodies (aORCS = 5.65; aORAPOs = 1.47), early syphilis (aORCS = 23.24; aORAPOs = 26.95), and non-penicillin treatment (aORCS = 3.00; aORAPOs = 2.16), as well as paternal history of cocaine use (aORCS = 2.70; aORAPOs = 2.44) and positive (aORCS = 4.14; aORAPOs = 1.50) or unknown (aORCS = 2.37; aORAPOs = 2.06) status of syphilis increased the risk of CS and APOs. Condom use (aOR = 0.70) decreased MTCT of syphilis. A ten-year program consisting of screening and treatment, early ANC, health education, partners tracking, detection, and treatment, follow-up visits, and information management is an effective means to block MTCT of syphilis. Maternal and paternal factors constituted two separate profiles associated with MTCT of syphilis.

Condom use is often equated to safer sex. The prevalence of condom use during sex work among female sex workers (FSW) in China is high. Condom use, however, co-exists with condom failure and improper use and hence risk of HIV transmission. In a cross-sectional study, we interviewed 195 FSW in Shenzhen, China. The prevalence of condom use in the last episode of sex work was 97.4 %, However, respectively 53.8 and 86.2 % had experienced at least one condition of condom failure that may lead to genital contact (wearing condoms after penetration, condom breakage/slippage, condoms removed by clients) and at least one condition of improper condom use (not removing air from the tip of the condom, not pulling it down to the root of penis and not choosing good quality condoms). Factors of individual level (e.g. never choosing high quality condoms for sex work), inter-personal level (e.g. agreement to have unprotected sex if fond of clients or paid more) and environmental/structural level (e.g. non-availability of condoms) were associated with various types of condom failure and improper use. Although HIV prevention interventions have increased prevalence of condom use among FSW, the risk of HIV transmission may still be high as "unsafe" sex due to condom failure and improper use is prevalent. Interventions promoting safer sex need to address such issues and take socio-ecological factors into account. Condom use during sex work is not equivalent to well protected sex as the protective effects could be compromised by frequent condom failure and improper use.

Background: An increasing incidence of anal cancer among men, especially men who have sex with men (MSM) suggests a need to better understand anal human papillomavirus (HPV) infection among this group., Methods: A cross-sectional study was conducted among MSM in Shenzhen, China. Blood was collected for HIV serological testing and syphilis serological screening, and anal swabs were collected for HPV genotyping. Difference of HPV prevalence between HIV seropositive and HIV seronegative MSM was assessed by chi-square test. Factors associated with anal canal HPV infection were assessed by univariate and multivariate logistic regression., Results: A total of 408 MSM were recruited. HIV and HPV prevalence were 6.9% and 36.4%, respectively. HPV was detected in the anal canal in 71.4% of the HIV-positive MSM and in 33.8% of the HIV-negative MSM (P<0.001). Oncogenic types were seen more often in anal specimens of HIV-positive MSM than in specimens of HIV-negative MSM (P = 0.001). The HPV genotypes detected most frequently were HPV06 (8.2%), HPV16 (7.2%), HPV11 (6.4%), HPV18 (4.7%), HPV58 (4.7%), and HPV52 (4.2%)., Conclusions: In this study, HIV positive MSM had a higher burden of HPV infection, especially oncogenic HPV infection. HPV types 52 and 58 were as popular as those types designed for the currently available vaccine (HPV6, 11, 16, 18).

Background: Untreated maternal syphilis can result in the fetuses being infected. Severe adverse pregnancy outcomes include stillbirth, perinatal death, low birth weight, and congenital syphilis (CS). The World Health Organization has already classified global elimination of CS as a priority. However, this preventable disease is still threatening people's health in the world., Methods: A Programme of Prevention of Mother-to-Child Transmission of Syphilis in Shenzhen was launched in 2002. All pregnant women in Shenzhen were screened for syphilis by serological methods at their first prenatal care visit. The infected individuals were treated with 3 weekly injections of 2.4 million units of benzathine penicillin. The babies were followed up until 18 months old to diagnose CS., Results: Up to 2011, the Programme of Prevention of Mother-to-Child Transmission of Syphilis in Shenzhen screened 2,077,362 pregnant women and intervened in 7668 mothers infected with syphilis. The screened rate among pregnant women increased from 89.8% in 2002 to 97.4% in 2011. The proportion of those having adverse pregnant outcomes (including spontaneous abortion, premature delivery, and stillbirth) decreased from 27.3% in 2003 to 8.2% in 2011. The incidence of CS decreased from 115/100,000 in 2002 to 10/100,000 (live births) in 2011., Conclusions: In 2002, in the face of rising CS numbers, Shenzhen adapted a syphilis control program that involved cost-free testing for pregnant women, commitment and collaboration at multiple levels of the health system, and strong supervision and government guidance. Local program and surveillance data suggest that the program has been very successful in reducing CS incidence.

Maternal and paternal factors create considerable obstacles to the elimination of congenital syphilis (CS). A clear understanding of maternal and paternal factors is important in order to define interventions in every community. This study aimed to investigate the maternal and paternal factors associated with CS. A prospective cohort study was conducted from April 25, 2007 to October 31, 2012 at the Shenzhen Center for Chronic Disease Control and Prevention (SCCDC) in China. We screened 279,334 pregnant women and identified 838 women with syphilis. Finally, a total of 360 women with syphilis were included for analysis. At the end of follow-up, 34 infants [9.4 %, 95 % confidence interval (CI): 6.8-12.9 %] were diagnosed with CS. Following adjustment for confounders, maternal history of syphilis [adjusted risk ratio (aRR) = 0.21], prenatal care (aRR = 0.12), and complete treatment (aRR = 0.22) reduced the risk of infants being infected. Every two-fold increase of titer of non-treponemal antibodies (aRR = 1.88), early stage of syphilis (aRR = 9.59), a shorter length of time between the end of the first treatment to childbirth (aRR = 5.39), and every week of delay in treatment (aRR = 2.25) for maternal syphilis as well as paternal history of cocaine use (aRR = 6.28) and positive (aRR = 3.30) or unknown (aRR = 2.79) status of syphilis increased the risk of infants being infected. CS also increased the risk (aRR = 8.02) of neonatal death. Maternal and paternal factors constituted two separate profiles associated with CS. To become more effective, future strategies for the prevention of CS should be targeted to each profile.

Few studies compared HIV-related risk behaviors between cities with different sociocultural environments among men who have sex with men (MSM). This study investigated the prevalence of unprotected anal intercourse (UAI) and associated individual and socio-cultural factors among Chinese MSM in Hong Kong and Shenzhen in Mainland China, which were proximal to each other but experienced different socioeconomic developments. Amongst all the 535 participants, 40.2% had had UAI. Significant factors of UAI among Shenzhen MSM included being able to find someone to share one's sexual orientation, disclosure of sexual orientation to family members, HIV risk perception, and use of alcohol or substances (adjusted OR ranged from 2.37 to 4.91), whilst disclosure of sexual orientation to family members was the only significant factor among Hong Kong MSM (adjusted OR = 1.64). Geographic variations in factors associated with UAI were observed. Future research and interventions need to take this into account.

Background: Despite existence of a highly effective intervention, maternal syphilis still causes substantial perinatal morbidity and mortality, even in China, where antenatal health services are strong. This study sought to address personal, programmatic, and other risk factors for congenital syphilis (CS) and adverse pregnancy outcomes (APOs) among pregnant women in Shenzhen, China., Methods: Pregnant women attending antenatal services were offered serologic tests, and those diagnosed as having syphilis were recruited from April 2007 to October 2012. In a nested case-control study for the pregnancy outcomes of syphilis-infected women, we assessed risk factors comparing infants born with CS (group II) and with any APOs (group III) to infants without CS or APOs (group I)., Results: During the 66-month study period, we screened 279,334 pregnant women and identified 838 (0.3%; 95% confidence interval, 0.28%-0.32%) women infected with syphilis. Among infants born to syphilitic mothers, 8.2% (34/417) were diagnosed as having CS and 24.7% (103/417) were diagnosed as having APOs. Compared with group I, maternal baseline titers of nontreponemal antibodies (adjusted odds ratio [aOR], 2.13), stage of syphilis (aOR, 21.56), length of time between the end of the first treatment to childbirth (aOR, 11.93), gestational week at treatment (aOR, 2.63), and fathers' cocaine use (aOR, 15.44) and syphilis infection status (aORpositive vs. negative, 5.84; aORunknown vs. negative, 5.55) were positively associated with CS, but prenatal care (aOR, 0.11) and complete treatment (aOR, 0.20) were negatively associated with CS. Maternal age (aOR, 1.43), marriage (aOR, 2.41), history of cocaine use (aOR, 3.79) and ectopic pregnancy (aOR, 5.91), baseline titers of nontreponemal antibodies (aOR, 1.30), stage of syphilis (aOR, 8.89), length of time between the end of the first treatment to childbirth (aOR, 2.52), gestational week at treatment (aOR, 1.78), and fathers' syphilis infection status (aORunknown vs. negative, 2.02) were also positively associated with APOs, but maternal history of syphilis (aOR, 0.44), prenatal care (aOR, 0.29), and complete treatment (aOR, 0.25) were negatively associated with APOs,, Conclusions: Syphilis was an important cause of pregnancy loss and infant disability, particularly among women who did not receive prenatal care or had late or inadequate treatment. These study results can inform antenatal programs on the importance of early syphilis testing and prompt and appropriate treatment. Some strategies targeted at other risk factors areas may be helpful.

The creation of nanostructures on polycrystalline silicon wafer surface to reduce the solar reflection can enhance the solar absorption and thus increase the solar-electricity conversion efficiency of solar cells. The self-masking reactive ion etching (RIE) was studied to directly fabricate nanostructures on silicon surface without using a masking process for antireflection purpose. Reactive gases comprising chlorine (Cl 2 ), sulfur hexafluoride (SF 6 ), and oxygen (O 2 ) were activated by radio-frequency plasma in an RIE system at a typical pressure of 120-130 mTorr to fabricate the nanoscale pyramids. Poly-Si wafers were etched directly without masking for 6-10 min to create surface nanostructures by varying the compositions of SF 6 , Cl 2 , and O 2 gas mixtures in the etching process. The wafers were then treated with acid (KOH:H 2 O = 1:1) for 1 min to remove the damage layer (100 nm) induced by dry etching. The damage layer significantly reduced the solar cell efficiencies by affecting the electrical properties of the surface layer. The light reflectivity from the surface after acid treatment could be significantly reduced to <10% for the wavelengths between 500 and 900 nm. The effects of RIE and surface treatment conditions on the surface nanostructures and the optical performance as well as the efficiencies of solar cells will be presented and discussed. The authors have successfully fabricated large-area (156 × 156 mm 2 ) subwavelength antireflection structure on poly-Si substrates, which could improve the solar cell efficiency reproducibly up to 16.27%, higher than 15.56% using wet etching.

Aligned GaN nanowire arrays have high potentials for applications in future electronic and optoelectronic devices. In this study, the growth of GaN nanowire arrays with high degree of vertical alignment was attempted by plasma-enhanced CVD on the c-plane GaN substrate. We found that the lattice matching between the substrate and the nanowire is essential for the growth of vertically aligned GaN nanowires. In addition, the initial nucleation process is also found to play a key role in creating the high-quality homoepitaxy at the nanowire-substrate interface. By controlling the nucleation stage, the growth of highly aligned vertical GaN nanowire arrays can be achieved. The reasons for the observed effects are discussed.

Objective: To evaluate the status of drug resistance among treat-naive HIV-1 infected men who have sex with men (MSM) in Shenzhen during the period of 2008 - 2010., Methods: Plasma samples of 227 treatment-naive HIV-1 infected MSM were collected in Shenzhen. HIV-1 pol genes (RT and PR) were amplified by nested-polymerase chain reaction (PCR) from RNA. Phylogenetic and drug resistance analyses were performed on the nucleotide sequence data., Results: A total of 164 pol gene sequences were amplified. The prevalence of primary genotypic drug resistance was 14.6%. The overall prevalence of drug-resistant mutations was 22.6%, corresponding to 8.54% for protease inhibitors (PI) minor drug resistance mutation, 1.22% for nucleotide reverse transcriptase inhibitors (NRTI) drug resistance mutation and 13.41% for non-nucleotide reverse transcriptase inhibitors (NNRTI) drug resistance mutation. The prevalence of drug-resistant mutations was 30.88% for CRF01&#95;AE strain and 19.23% for B strain., Conclusion: The prevalence of drug resistance is relatively moderate in the treat-naive HIV-1 infected MSM in Shenzhen. The prevalence of drug-resistant HIV-1 among MSM in Shenzhen should raise a high alert.

Objective: To investigate the epidemiological characteristics of HIV-1 subtype in Shenzhen from 1992 to 2008., Methods: 489 HIV-1 positive plasma samples were collected from 1992 to 2008 in Shenzhen. HIV-1 env genes were amplified by nested-PCR from RNA. Phylogenetic analysis was performed on data regarding the nucleotide sequence., Results: A total of 464 sequences were amplified and genotyped. Data from this study revealed that CRF01&#95;AE was a predominant HIV-1 subtype in Shenzhen (64.4%, 299/464), followed by subtypes CRF&#95;BC (17.5%, 81/464), B' (14.7%, 68/464) and B (2.4%, 11/464). Subtype C (0.4%, 2/464), A1 (0.2%, 1/464), CRF02&#95;AG (0.2%, 1/464) and CRF06&#95;cpx (0.2%, 1/464) were also prevalent in Shenzhen. CRF01&#95;AE and CRF&#95;BC were predominant among heterosexuals, homosexuals and injection drug users, while B' was predominant among blood donors. Results from phylogenetic tree analysis showed that some of the HIV-1 clusters had been defined in CRF01&#95;AE strains at different time or groups with different transmission routes. Cross-infections were also seen., Conclusion: CRF01&#95;AE was the predominant HIV-1 subtype in Shenzhen while CRF&#95;BC, B, B', C, A1, CRF02&#95;AG and a small amount of CRF06&#95;cpx or recombinant subtypes were prevalent in this city. Different subtypes showed great variation in the process of epidemics.

In this study, we have used an agarose stamp to conduct direct printing of silver nanoparticles, nanowires and nanoplates on both planar and structured substrates. Nanoparticle solution could be first coated on an agarose stamp, and then transferred to a planar substrate. Micro-patterns comprising metal nanoparticles could be printed on planar substrates without the formation of residual layers. Thus a three-dimensional metal microstructure could be easily fabricated. The patterning of electrodes by printing Ag nanowires directly on TiO(2) was also demonstrated to fabricate resistive random access memory (RRAM) devices by all-solution-processing methods. By using a flat agarose stamp, the patterns printed on the microstructured substrates were quite different from those on the nanostructured substrates. On the microstructured substrates, direct printing could print silver nanoparticles onto the protrusion surface, and could print silver layers as thick as several microns, useful for high conductivity electrodes. On the substrates with nanostructures such as photonic crystals or nano-gratings, direct printing could transfer nanoparticles into the grooves or cavities only due to the contact of the agarose stamp with the groove or concavity surface. A new approach to fabricate metal wire grid polarizers was further demonstrated. A nanoporous agarose stamp has a good potential for printing using nanoparticle suspension.

Objective: Tranexamic acid reduces blood loss and transfusion in on-pump coronary artery bypass graft (CABG) surgery. Compared with on-pump, off-pump surgery is associated with less blood loss and transfusion. Therefore, tranexamic acid may be less effective for off-pump surgery, and its safety profile may be different in this setting. The aim of this study was to determine the efficacy and safety of tranexamic acid for off-pump CABG surgery., Design: Systematic review and meta-analysis., Setting: University of Edinburgh., Interventions: The administration of tranexamic acid., Methods: A systematic review of randomized controlled trials administering tranexamic acid to patients undergoing off-pump CABG surgery. A meta-analysis of 24-hour blood loss, postoperative allogeneic transfusion, and thromboembolic events., Measurements and Main Results: Eight trials were identified. The lack of appropriate data limited the meta-analysis on blood loss. Tranexamic acid significantly reduced the overall risk of allogeneic blood component transfusion (risk ratio = 0.47; 95% confidence intervals, 0.33-0.66; p < 0.0001) and packed red blood cell transfusions (risk ratio = 0.51; 95% CI, 0.36-0.71; p = 0.0001). No association was found between tranexamic acid and myocardial infarction, stroke, or pulmonary embolism. Population sizes of meta-analyses ranged from 466 to 544., Conclusions: Tranexamic acid reduces blood transfusion after off-pump surgery. Although no association with adverse events was found, the population sample size was too small to detect rare but clinically significant adverse events. A well-designed randomized controlled trial with an appropriate sample size is required to confirm tranexamic acid effectiveness and safety in off-pump CABG surgery., (Copyright © 2011 Elsevier Inc. All rights reserved.)

To investigate the prevalence and genotype distribution of Chlamydia trachomatis infection among men who have sex with men (MSM), 145 MSM from two sauna settings in Shenzhen, China were invited to participate in this study during September 2008 and May 2009. Anorectal swab and urine samples were collected and tested for chlamydial infection, and positive samples were genotyped. The prevalence of anorectal chlamydial infection was 24% in the study population and was significantly associated with proctitis symptoms. Up to 50% of the anorectal infections were asymptomatic. The most prevalent genotypes were G (39%) and D (37%), followed by J (11%). Genotypes related to lymphogranuloma venereum were not found in the study population. The high prevalence of anorectal infection in MSM suggests the importance of detecting and treating the infection in this population.

Introduction: Consistent definitions of congenital syphilis are critical for determining true incidences and setting up targets of elimination. This study aimed to assess the evaluation and management of infants at high risk of congenital syphilis with an antenatal syphilis-screening programme in the Shenzhen SEZ and to develop feasible definitions for the detection of congenital syphilis in China., Methods: A retrospective study was conducted of all standardised records of pregnant women with positive syphilis between 2003 and 2007. Infants at high risk of congenital syphilis were evaluated by laboratory tests at birth and longitudinal follow-up. A screening test-positive congenital syphilis case was defined based on a positive 19S-IgM-FTA-ABS result at birth. Assuming that 19S-IgM-FTA-ABS was the gold standard, the sensitivity and specificity of the ascertainment methods were calculated., Results: During the study period, 1010 live infants were born to women with active syphilis during pregnancy. 19S-IgM-FTA-ABS detected 42 screening-positive congenital syphilis cases and another nine cases were identified by longitudinal follow-up only. Using 19S-IgM-FTA-ABS as the gold standard, 'fourfold rapid plasma reagin (RPR) titres' had the highest sensitivity and specificity compared with the other two follow-up methods., Discussion: 19S-IgM-FTA-ABS makes congenital syphilis case classification simpler and faster for newborns. In areas where 19S-IgM-FTA-ABS is not available, comparing newborn RPR titres with maternal titres can be an alternative method. Meanwhile, positive follow-up results act as treatment indicators for older infants. As congenital syphilis definitions vary over the country, the Shenzhen programme suggested a practical model for surveillance and treatment in areas with or without available 19S-IgM-FTA-ABS testing.

Objective: To learn the spatial and temporal patterns of primary syphilis and secondary syphilis in Shenzhen and to provide evidence for carrying out further research on syphilis., Methods: Primary syphilis and secondary syphilis cases among residents in Shenzhen between 2005 and 2009 (n = 11 303) were geocoded at street office level (n = 55) based on residence at the time of diagnosis. Both spatial and space-time scan statistics were used to identify clusters of street office by using SaTScan software., Results: In the purely spatial analyses, clusters were seen in the junction of the Baoan district and Nanshan district (Xinan, Xixiang, Nanshan and Nantou street office) and in the region near Hong Kong (Dongmen, Shekou, and Futian street office), as well as in the other streets where entertainment industry was relatively developed (Longhua, Huafu, Huangbei and Cuizu street office). The clusters had not changed much in the first four years, but nine clusters appeared in 2009. Annually, the most likely clusters were located in Longhua (2005, P ≤ 0.001, RR = 3.34), Bamboo (2006, P ≤ 0.001, RR = 9.59), Huafu (2007, 2008 years, P ≤ 0.001, RR values were 4.18 and 4.75) and Cuizu (2009, P ≤ 0.001, RR = 8.02). In the space-time scan analysis, we found 16 significant clusters, which were similar to the pure spatial analyses. However, regional difference were also found, with the most likely cluster was the Guiyuan street office in 2006., Conclusion: Spatial and space-time scan statistics seemed to be effective ways in describing the circular disease clusters. We have had a better understanding on spatial and temporal patterns of primary syphilis and secondary syphilis in Shenzhen through spatial and space-time scan statistics of syphilis surveillance data in the recent years. The changes of spatial and temporal patterns of primary syphilis and secondary syphilis were also described by SaTScan software, which also provided useful reference for the preventive strategies on sexually transmitted diseases as well as on HIV. Useful information was also provided for financial investment and cost-effective studies.

Objective: To explore the risk factors underlying congenital syphilis (CS) and to build a hazards model to assess the risk of CS in offspring born to mothers with syphilis treated in gestation., Methods: This prospective study observed 554 pregnant women with syphilis and their offspring recruited from August 2002 to May 2007 in Shenzhen Centre for Chronic Disease Control and Prevention. After treatment, all the women were followed up until the diagnosis of CS in their offspring was confirmed or denied. Comparisons were made between women bearing infants with CS and women bearing infants without CS to reveal the risk factors for CS. ORs and their 95% CI were calculated for each risk factor by using logistical regression analysis., Results: Twenty-nine (5.2%) infants were diagnosed with CS. Univariable analyses showed that the reciprocal logarithm of the titre of non-treponemal antibodies in mothers (log (1/T); OR=11.18, p<0.001), gestational week (GW) at treatment (OR=1.10, p<0.001) and the interaction between these two variates (OR=1.09, p<0.001) was associated with CS. Multivariable analysis showed that only the interaction was significantly associated with CS (OR=1.09, p=0.047)., Conclusions: The risk of CS could be predicted by the interaction between GW x log (1/T). Early treatment given to women with syphilis during antenatal care may be the only effective method to decrease the risk of CS.

Background: Until now there has been no data to show the effectiveness or benefits of screening for syphilis in gravidas in China. This study was to assess the effectiveness of a program preventing mother-to-child-transmission of syphilis and to reveal factors impacting the benefit., Methods: A cohort of 159,017 gravidas were screened for syphilis by serologic methods and infected individuals were treated with 3 injections of 2.4 million units of benzathine penicillin in Shenzhen in 2005. The pregnancy outcomes were compared for this cost-effectiveness analysis in 2 scenarios, intervention with screening and treatment versus no intervention., Results: Eight hundred twenty-seven pregnant women (0.52%) were diagnosed with syphilis and treated subsequently. Of these, 200 gestations ended in miscarriage. Four babies were diagnosed with congenital syphilis; 25 neonates with low birth weight; 1 died after birth. The total cost was $636,748. On average, every $770 identified 1 infected mother. Every $4391 prevented 1 congenital syphilis; every $5135 prevented 1 low birth weight; and every $7075 prevented 1 death. One disability adjusted life year could be saved by $215. In total the program reached a benefit to cost ratio of 21.76. Sensitivity analyses revealed that this ratio was mainly impacted by the prevalence of syphilis in pregnant women and the rate of miscarriage., Conclusions: Screening for antenatal syphilis combined with intervening during gestation is highly effective in China. Reducing the percentage of spontaneous/induced abortion would be one of the most effective methods of further increasing the benefits of this screening.

Zinc oxide nanowire field-effect transistors (NW-FETs) were fabricated combining the dielectrophoresis (DEP) and the hot-pressing methods. DEP was used to position both ends of the nanowires on top of the source and the drain electrodes, respectively. Hot-pressing of nanowires on the electrodes was then employed to ensure good contacts between the nanowires and the electrodes. The good device performance achieved with our method of fabrication indicates that DEP combined with hot-pressing has the potential to be applied to the fabrication of flexible electronics on a roll-to-roll basis.

A method with the potential to fabricate large-area nanowire field-effect transistors (NW-FETs) was demonstrated in this study. Using a high-speed roller (20-80 cm min(-1)), transfer printing was successfully employed to transfer vertically aligned zinc oxide (ZnO) nanowires grown on a donor substrate to a polydimethylsiloxane (PDMS) stamp and then print the ordered ZnO nanowire arrays on the received substrate for the fabrication of NW-FETs. ZnO NW-FETs fabricated by this method exhibit high performances with a threshold voltage of around 0.25 V, a current on/off ratio as high as 10(5), a subthreshold slope of 360 mV/dec, and a field-effect mobility of around 90 cm(2) V(-1) s(-1). The excellent device characteristics suggest that the roll-transfer printing technique, which is compatible with the roll-to-roll (R2R) process and operated in atmosphere, has a good potential for the high-speed fabrication of large-area nanowire transistors for flexible devices and flat panel displays.

This study investigates the growth of GaN nanowires by controlling the surface diffusion of Ga species on sapphire in a plasma-enhanced chemical vapor deposition (CVD) system. Under nitrogen-rich growth conditions, Ga has a tendency to adsorb on the substrate surface diffusing to nanowires to contribute to their growth. The significance of surface diffusion on the growth of nanowires is dependent on the environment of the nanowire on the substrate surface as well as the gas phase species and compositions. Under nitrogen-rich growth conditions, the growth rate is strongly dependent on the surface diffusion of gallium, but the addition of 5% hydrogen in nitrogen plasma instantly diminishes the surface diffusion effect. Gallium desorbs easily from the surface by reaction with hydrogen. On the other hand, under gallium-rich growth conditions, nanowire growth is shown to be dominated by the gas phase deposition, with negligible contribution from surface diffusion. This is the first study reporting the inhibition of surface diffusion effects by hydrogen addition, which can be useful in tailoring the growth and characteristics of nanowires. Without any evidence of direct deposition on the nanowire surface, gallium and nitrogen are shown to dissolve into the catalyst for growing the nanowires at 900 degrees C.

HIV/STD surveillance system data are important for developing prevention and control programmes for men who have sex with men (MSM), now a core group in Chinese HIV/STD surveillance activities. MSM were recruited from different settings in Shenzhen and were tested for HIV and syphilis. A substantial prevalence of HIV and syphilis infections was found in this population. However, risk behaviours and sociodemographic characteristics varied greatly among MSM recruited from the different settings (gay sauna, gay bar and MSM clinic), suggesting that carefully considering and selecting appropriate settings to represent the MSM population is critical for developing HIV and STD surveillance and prevention programmes.

Information on the prevalence and incidence of sexually transmitted infections is important for developing prevention and control strategies and allocating human and financial resources. However, there are no available estimates of such information for many areas in China. In this study, we used the existing data to make a preliminary estimation of syphilis infections in Shenzhen city, in south-eastern China. Data on prevalence rates of syphilis infections among different populations were obtained from the local HIV/sexually transmitted disease second-generation surveillance programme, and the sizes of different populations were estimated based on the most recently available figures. It was estimated that 83,760 (range 77,490-90,020) people are currently infected with syphilis, giving a prevalence of 0.71-0.82% (0.76% on average) in Shenzhen. Around 18% of these syphilis infections occur among men who have sex with men and another 15.8% and 8.7% occur among female sex workers and their clients, respectively. These estimates suggest that a combination of unprotected paid sex and sex between men may be sustaining the epidemic of syphilis in the study area. The preliminary estimates will assist the government in planning and improving its comprehensive intervention programmes for the future control and prevention of syphilis.

Objective: Through questionnaire and screening, epidemiology of syphilis in pregnant women and related risk factors were studied, to develop effective policy and reducing the negative impact of the disease., Methods: All pregnant women who appeared at the hospitals the first time, were included, in Shenzhen city. Tolulized Red Unheated Serum Test (TRUST) method was used for primary screening and positive results were confirmed by the Treponema Pallidum Particle Agglutination (TPPA) test at the Shenzhen Center for Disease Control and Prevention (SZCDC). Positive patients were informed and treated and the pregnancies were managed accordingly at the SZCDC., Results: From 2003-2005, 418,871 (94.7%) pregnant were screened. Epidemiological and treatment data were collected from 2019 positive cases of infectious syphilis (0.48%). Among them, 94.2% were between 20 and 35 years old, with 93.6% of them had only junior high school education and 63.4% of them worked as commercial services or jobless which was significantly higher than other occupations (OR = 8.628). 89.5% of them were from other cities, significantly higher than from local residents (OR = 8.733). Gestational weeks at original diagnosis was longer and the infection rate higher., Conclusion: The infection rate of syphilis in Shenzhen was still at a high level which was related to occupation, education level, place of residency, gestational weeks at first diagnosis etc. Further screening measures and early intervention were important.

Background: China has been experiencing a rapidly growing syphilis epidemic since the early 1990s, with the reported incidence of congenital syphilis increasing from 0.01 cases per 100,000 live births in 1991 to 19.7 cases per 100,000 live births in 2005. Detailed studies of risk factors for syphilis in pregnant women are needed to inform new preventive interventions., Objective: To investigate factors associated with recent syphilis infection among pregnant women and recommend strategies for improved preventive interventions in the community., Methods: A case-control study was conducted among women attending antenatal clinics in Shenzhen City, South China. Cases were antenatal clinic women testing positive for early syphilis, based on laboratory results, with those testing negative being controls. All participants completed the same anonymous questionnaire covering demographics, lifestyle, sexual behaviour, and sexual partnerships., Results: 129 cases and 345 controls were recruited. Syphilis was significantly associated with unmarried status, less education, multiple sex partners, travel of sex partner in the past 12 months, a history of induced abortion, and previous sexually transmitted infections. Overall, there were no differences between syphilis-positive and negative women in household registration status (hukou), living district and duration in Shenzhen, monthly income, and age at first sex., Conclusions: Many demographic and behavioural risk factors are associated with syphilis among pregnant women. In the government congenital syphilis control programme, comprehensive preventive interventions should be provided in all clinical settings in addition to the current procedures for syphilis screening among antenatal women.

Objectives: To understand the disease epidemiology of syphilis in pregnant women, and to evaluate the effectiveness of the screening and intervention programme, for the purpose of controlling mother-to-child syphilis transmission in Shenzhen, in the People's Republic of China (PRC)., Methods: At the Shenzhen Center for Disease Control and Prevention (SZCDC), we used the toluidine red unheated serum test (TRUST) for the primary screening of pregnant women, and confirmed positive results with the Treponema pallidum particle agglutination (TPPA) test. We informed and treated those with positive results. For the women who chose to proceed with the pregnancy, we clinically screened their babies for congenital syphilis using the 19S-IgM FTA-Abs test., Results: Between 1 July 2002 and 31 December 2005, we screened 477,656 pregnant women for syphilis, of whom 2208 (0.5%) tested positive. From 2003 to 2005, we collected epidemiological and treatment data from 2019 positive syphilis cases. Of these, 1855 (91.9%) of the pregnant women received treatment. Among the 1020 infants born to these women, 92 (9.0%) were confirmed to have congenital syphilis. If we exclude the mothers who had syphilis positive babies without undergoing prenatal screening, the project's success rate for mother-to-child transmission intervention was 99.1%., Conclusions: After four years of implementation, we proved the programme to be successful in preventing mother-to-child syphilis transmission. Further work should be done to ensure the earlier screening and treatment of pregnant women.

Background: To describe the use of anterior segment optical coherence tomography (OCT) in imaging intrableb morphology after trabeculectomy., Methods: 14 post-trabeculectomy eyes from 11 primary open angle glaucoma and 3 primary angle closure glaucoma subjects were studied. The blebs were classified with reference to slit lamp morphology and bleb function. They included diffuse filtering (n = 7), cystic (n = 2), encapsulated (n = 2) and flattened (n = 3) bleb types. One eye in each patient was imaged with the Visante anterior segment OCT. A vertical scan line of 10 mm consisting of 512 A-scans was positioned at the centre of the bleb. The images were then analysed by built-in software. Intrableb morphologies and structures, including bleb wall thickness, subconjunctival fluid collections, suprascleral fluid space, scleral flap thickness, intrableb intensity (low, medium or high) and the route under the scleral flap were characterised and measured., Results: Diffuse filtering blebs were found by subconjunctival fluid collections. Suprascleral fluid space and the route under the scleral flap were identified in four of the seven cases. Cystic blebs were composed of a large hyporeflective space with multiloculated fluid collections covered by a thin layer of conjunctiva. Encapsulated blebs had a thick bleb wall with high reflectivity and an enclosed fluid filled space. Flattened blebs demonstrated high scleral reflectivity and no bleb elevation., Conclusions: Visante anterior segment OCT can be used for bleb imaging. The different patterns of intrableb morphology identified by OCT were related to slit lamp appearance and bleb function. This information may be useful to study the different surgical outcomes and the process of wound healing in trabeculectomised eyes.