To address the security challenges of underwater wireless sensor networks (UWSNs) in complex and hostile environments, this paper investigates the physical-layer secrecy performance of the transmitter-receiver link, with particular emphasis on transmission optimization under eavesdropping threats. We formulate a non-linear, non-convex optimization problem that jointly allocates sub-channels and transmission power to maximize the secrecy rate while considering the inherent constraints of underwater acoustic communication. To efficiently solve this problem, we develop a deep reinforcement learning (DRL)-based resource allocation algorithm that integrates a prioritized experience replay mechanism, thereby enhancing learning efficiency and improving optimization performance. Extensive simulations are conducted to assess the convergence and adaptability of the proposed method under varying node densities and maximum transmission power levels. The results demonstrate that the proposed algorithm consistently achieves higher system security, greater stability, and faster convergence compared to several benchmark schemes.

This paper investigates the problem of distributed resource management in underwater acoustic communication networks (UACNs) involving multiple transmitters and receivers. In this setting, each transmitter autonomously selects a power allocation strategy based solely on local observations, without reliance on a central controller. Given that the optimization problem incorporating fairness and quality of service (QoS) constraints is non-convex and NP-hard, it is reformulated as a Markov Decision Process (MDP). To address the high complexity of underwater networks and the large state and action spaces, we propose a distributed learning framework based on a multi-agent dueling deep Q-network (MAD3QN). The proposed scheme enables each transmitter to dynamically adjust its transmission power based on local observations by integrating the Jain fairness index, QoS interruption penalty, and energy consumption constraints. Furthermore, by incorporating a dueling network architecture and a neighborhood cooperation mechanism, the learning efficiency is significantly enhanced, leading to a stable and effective resource optimization policy. Simulation results demonstrate that the proposed distributed learning algorithm outperforms existing approaches in terms of convergence speed, network fairness, and communication rate.

BackgroundChina has recently implemented a strategy to promote and facilitate community organization involvement in HIV prevention among men who have sex with men (MSM). Although community-based strategies have been shown to increase HIV testing uptake, the relative effectiveness of mobile social media promotion compared with volunteer-driven recruitment remains underexplored. Limited research has investigated how these strategies differentially affect MSM who have not undergone previous HIV testing. ObjectiveThis study aimed to compare the differences between a mobile social media promotion strategy and a volunteer-driven strategy for community organizations to recruit MSM for HIV testing. MethodsA cross-sectional study was conducted from July to December 2023 among MSM in Zhejiang Province, China. Participants aged 16 years with an HIV-negative or unknown status were recruited either through a mobile social media promotion strategy or through a volunteer-driven strategy by a community organization. They completed a questionnaire that collected information on demographics, sexual behavior, and HIV testing history. All participants were tested for HIV after completing the questionnaire. A multivariate logistic regression model was used to identify factors associated with recruitment through mobile social media promotion. ResultsThe study included 4600 MSM, of whom 3035 (66%) were recruited through the mobile social media strategy. Overall, 1.4% (66/4600) of participants tested positive for HIV, and 18.8% (865/4600) underwent HIV testing for the first time. Recruitment via the mobile social media promotion strategy was significantly associated with several factors: having only gay sexual partners (adjusted OR [aOR] 1.23, 95% CI 1.05-1.45), having more than 2 sexual partners in the past 3 months (aOR 1.74, 95% CI 1.42-2.11), frequently using rush poppers during sex (aOR 1.39, 95% CI 1.14-1.99), having a history of sexually transmitted infections (aOR 1.56, 95% CI 1.02-2.39), having awareness of pre-exposure prophylaxis (aOR 1.42, 95% CI 1.19-1.71), having awareness of postexposure prophylaxis (PEP; aOR 1.49, 95% CI 1.24-1.79), using mail-in HIV self-testing kits (aOR 2.02, 95% CI 1.77-2.31), testing HIV-positive (aOR 2.02, 95% CI 1.10-3.72), and first-time HIV testing (aOR 1.28, 95% CI 1.09-1.52). ConclusionsCommunity organizations play a critical role in expanding HIV testing and identifying undiagnosed individuals infected with HIV. Compared to the volunteer-driven outreach, mobile social media promotion strategies had a higher proportion of first-time testers and a higher rate of HIV positivity. We recommend prioritizing mobile social media strategies in regions with limited LGBTQ+ organizations or HIV health services to increase HIV testing coverage and interventions among MSM.

Existing adaptive modulation and coding schemes suffer from performance degradation under time-varying underwater acoustic (UWA) channels and jamming attacks, resulting in increased video jitter and energy consumption, as well as reduced peak signal-to-noise ratio (PSNR). In this article, we first propose a reinforcement learning (RL)-based underwater video transmission scheme, which jointly optimizes the channel coding methods, subcarrier modulation order, quantization parameter, and transmit power against jamming. The direct sequence spread spectrum (DSSS) mechanism is used to reduce the jamming power in each subcarrier frequency band, which ensures that the transmitter obtains a reliable feedback message. In addition, a multi-frame statistics scheme is designed to support transmission policy selection, which mitigates the impact of channel instability by averaging the observed transmission performance and channel gain. To further enhance communication performance and robustness under large state-action spaces and dynamic channel conditions, we propose a deep RL (DRL)-based anti-jamming video transmission scheme to compress the excessive state-action space, mitigate quantization errors, and improve transmission stability. Two target networks are employed in DRL to ensure learning stability by mitigating fluctuations in Q -value and R -value updates caused by the time-varying channel. In addition, the performance bounds of transmission delay and energy consumption related to modulation order and channel coding rate are derived. Simulation and experimental results demonstrate that our schemes improve the video transmission performance by reducing transmission delay, energy consumption, and video jitter while increasing the PSNR and video quality compared with the benchmarks.

Oral emtricitabine-tenofovir disoproxil fumarate (F/TDF) for HIV pre-exposure prophylaxis (PrEP) demonstrates dual potential through antiviral activity against hepatitis B virus (HBV). While F/TDF lacks activity against hepatitis C virus (HCV), the use of F/TDF for HIV PrEP may elevate HCV risk through risk compensation. This study aims to investigate HBV/HCV incidence among men who have sex with men (MSM) using F/TDF-based HIV PrEP, addressing evidence gaps in low- and middle-income countries. We conducted a secondary analysis of the China Real-World Oral Intake of PrEP (CROPrEP) study, a multicenter prospective cohort of MSM (F/TDF users/non-users) from Beijing, Shenyang, Shenzhen, and Chongqing. Participants underwent HBV/HCV testing at baseline and at the 12-month follow-up. Only HBV-susceptible (hepatitis B surface antigen-negative, hepatitis B surface and core antibody-negative) MSM were included in the secondary analysis, to calculate HBV incidence. The primary outcomes were HBV/HCV incidence rates at the 12-month follow-up. Bayesian Poisson regression identified HBV/HCV infection risk factors. The CROPrEP cohort prospectively recruited 1023 F/TDF users and 507 F/TDF non-users at baseline. This secondary analysis included 259 F/TDF users and 120 non-users identified as HBV-susceptible at baseline. At the 12-month of follow-up, no incident HBV infections occurred in the F/TDF users group, and only one incident HBV infection occurred in the F/TDF non-users group. The incidence of new HBV infections was 0.00/100 person-years (PY) [95 https://www.chictr.org.cn/showproj.html?proj=22916 .

BACKGROUND:Recombinant B-subunit/Whole Cell Cholera Vaccine (rBS/WC) represents a new and effective way to protect against and control diarrhea. A test-negative case-control study was conducted to investigate the cross-protective effect of cholera vaccine immunization against bacterial infectious diarrhea in a real-world setting. METHODS:Using a test-negative design, children aged 2-6 years with infectious diarrhea in Guangzhou City were selected as study subjects. A 1:4 propensity score matching based on the basic characteristics of the included study subjects, and vaccine effects were calculated after correcting for confounders. RESULTS:A total of 2796 children with laboratory-confirmed infectious diarrhea were enrolled in the study, and 316 pairs were successfully enrolled in the matching after Propensity Score Matching(PSM), totaling 1306. By conditional logistic regression analysis, The results showed that the total protective effect of ≥1 dose of rBS/WC vaccine against bacterial infectious diarrhea in children aged 2-6 years was 57.7 % (95 % CI: 30.3-74.3); the rBS/WC vaccine had the best protective effect of 74.8 % (95 % CI: 16.8-95.6) within 6 months of vaccination and then showed a decreasing trend. The vaccine's protective effect was 54.6 % (95 % CI: 22.1-73.5) against Salmonella and 69.2 % (95 % CI: -133.7-95.9) against Escherichia coli. Stratified analyses revealed higher point estimates of the protective effect obtained by vaccination among healthy children with good hygiene. CONCLUSIONS:These findings support the idea that the rBS/WC vaccination program is effective in the real world in preventing bacterial diarrhea in children. For people who are susceptible to bacterial diarrhea, the cholera vaccine is a good preventive option.

To investigate the prevalence of commercial sexual behaviour among university students engaging in casual sexual behaviour in Zhejiang Province, China, and to characterise those involved, in order to guide healthcare providers and school authorities in designing effective HIV prevention intervention programmes. A cross-sectional study was conducted in 13 universities in Zhejiang Province, China, in 2018, using an anonymous online questionnaire with stratified cluster random sampling. Univariate and multivariate logistic regression analyses were used to examine factors associated with commercial sexual behaviour among the 631 participants who reported engaging in casual sexual behaviour. Of the 631 participants who had casual sexual behaviour, 196 (31.1%) had engaged in commercial sexual behaviour. The following factors were associated with commercial sexual behaviour: being male (adjusted odds ratio [AOR] = 2.17, 95% confidence interval [CI]: 1.10, 4.70); having ever had casual sexual behaviour after drinking (AOR = 2.21, 95% CI 1.39, 3.54); finding casual sexual partners through the internet (AOR = 3.20, 95% CI 1.78, 5.81); and finding casual sexual partners through offline entertainment venues (AOR = 2.86, 95% CI 1.54, 5.32), receiving an HIV risk self-assessment at university (AOR = 1.86, 95% CI 1.21, 2.85), and perceiving themselves to be at risk of HIV infection (AOR = 3.40, 95% CI 2.02, 5.75) were associated with engaging in commercial sexual behaviour. Those who believed that they could tell if someone was infected with HIV by their appearance (AOR = 0.55, 95% CI 0.34, 0.88), knew that the Centres for Disease Control and Prevention offered HIV testing services (AOR = 0.51, 95% CI 0.28, 0.94) and who sometimes/often (AOR = 0.33, 95% CI 0.20, 0.56) or always (AOR = 0.31, 95% CI 0.17, 0.56) used condoms during sex were less likely to engage in commercial sexual behaviour. A significant proportion of Chinese university students engage in commercial sexual behaviour. Interventions need to target these high-risk males and raise awareness of the risks of alcohol consumption. They should also provide guidance on cautious use of internet dating platforms and entertainment venues and emphasise the importance of consistent condom use.

Aim:Men who have sex with men (MSM) contribute increasingly to the burden of HIV infection due to their high-risk sexual behaviors; however, studies focusing on the sexual behaviors among student MSM population remain limited. This study aims to investigate the incidence of HIV infection among MSM, while exploring high-risk sexual behavior in student MSM in Zhejiang province, China. Method:Prospective cohort study was conducted among MSM population in four cities in Zhejiang province. Information including socio-demographic characteristics as well as sexual behaviors were collected at baseline. Follow-up surveys and testing for HIV infection were conducted every 3 months. Univariable and multivariable logistic regression were performed to assess risk factors for HIV infection, investigate the sexual behavior differences between student and non-student MSM groups. Cox regression analyses were employed to discover potential association among various risk factors. Result:2081 HIV-negative MSM were enrolled in our cohort and 36 participants were infected with HIV. The incidence density of HIV infection was 2.15 per 100 person-years among this population. Student MSM are more likely to take sexual role of versatile (OR: 1.56, 95% CI: 1.05-2.32, p = 0.029) and receptive only (OR: 2.65, 95% CI: 1.62-4.08, p < 0.001) during anal intercourse, with a lower rate of previous HIV testing (OR: 0.45, 95% CI: 0.31-0.66, p < 0.001). Cox regression discovered that MSM who had more than 6 partners in anal sexual intercourse were more likely to obtain HIV-seroconversion than who had one fixed partner (HR: 5.14, 95% CI: 1.67-10.59, p < 0.001), participants who sometimes use condoms (HR: 4.11, 95% CI: 1.28-13.16, p = 0.017) and never use condoms (HR: 2.57, 95% CI: 1.16-5.66, p = 0.020) were more vulnerable to be infected by HIV compared to those use condoms constantly. Versatile (HR: 5.30, 95% CI: 1.65-17.06, p = 0.005) and receptive only role (HR: 3.23, 95% CI: 1.05-9.96, p = 0.042) in anal intercourse were more likely to be infected by HIV than insertive only. Conclusion:High-risk behaviors, particularly inconsistent condom uses during anal sex, significantly increase the risk of HIV infection. Student MSM exhibited persistent high-risk behaviors and low HIV testing rates. Greater attention and tailored interventions are needed to promote safer sexual practices and reduce HIV transmission in this population.

ObjectiveThis study aimed to investigate the occurrence of and factors associated with commercial sexual activities among college students who engaged in casual heterosexual behaviors in the past year.MethodsUsing an independent self-designed online survey questionnaire, information on demographic characteristics, attitudes towards sex, HIV prevention and control knowledge, and intervention acceptance was collected. Logistic regression analysis was used to determine factors associated with commercial sexual behavior among college students who had engaged in casual heterosexual behavior in the past year.ResultsIn total, 42,380 students were surveyed and 440 incomplete questionnaires were excluded, resulting in 41,940 valid responses. Among them, 2,581 college students reported involvement in heterosexual activities in the previous year, representing 6.15% of the total student population. Specifically, 425 college students reported engaging in casual heterosexual behavior in the previous year, accounting for 16.5% of students who engaged in heterosexual activities. Of these, 74 (17.4%) students had engaged in commercial sex (average age, 19.99 ± 1.22 years). Multivariate logistic regression analysis indicated that accepting commercial sex [adjusted odds ratio (aOR) 7.33, 95% confidence interval (CI) 3.24–16.58], opposite-sex partners being non-students (aOR2.48, 95% CI 1.24–4.99), recent anal intercourse (aOR3.11, 95% CI 1.33–7.28), seeking casual partners on the Internet rather than offline (aOR2.33, 95% CI 1.19–4.56), perceived risk of HIV infection (aOR2.93, 95% CI 1.13–7.59), and consistent condom use during casual sex (aOR0.27, 95% CI0.12–0.65) or sometimes/often use (aOR0.26, 95% CI0.11–0.64) compared with never using a condom were independent factors associated with the occurrence of commercial sex among college students who had engaged in casual heterosexual behaviors in the past year.ConclusionCommercial sexual activity among college students who engaged in casual heterosexual behavior was relatively common in Zhejiang Province, and was characterized with a high degree of openness towards sex, a low perception of HIV risk, low condom usage, and knowledge-practice separation. Strengthening HIV risk warnings and sex education tailored to this group is recommended, to promote the integration of knowledge and action, increase condom usage rates, and reduce the occurrence of unsafe sexual behavior.

Background:Vocational high school students in China exhibit higher rates of sexual activity than their academic counterparts; however, existing studies predominantly focus on college populations, leaving a critical gap in longitudinal data tracking the evolution of sexual knowledge and behavioural patterns among vocational students. This study aimed to evaluate changes over time in sexual safety knowledge, STIs/HIV and reproductive health-related sexual behaviours among boys who have had sex in Chinese vocational high schools. Methods:In 2015 and 2021, an anonymous survey was conducted separately using the same questionnaire and survey method among students in Years 1-2 of the same vocational high school in a district of Zhejiang Province. The results of the two surveys were compared using univariate analyses, and multivariate analyses. Results:In 2015 and 2021, 180 and 90 male students, respectively, had ever had sex, representing rates of 17.44% (180/1,032) and 8.49%(90/1,060). The results of the multivariate analysis showed that, in 2021, those who knew that sexual contact was the main mode of HIV transmission(OR = 14.14, 95% CI: 7.16-27.92), knew that contracting an STI increased the likelihood of HIV infection (OR = 7.83, 95% CI: 4.30-14.29), and knew that condom use could reduce both STIs(OR = 33.51, 95% CI: 15.08-74.49) and HIV infection(OR = 16.77, 95% CI: 8.58-32.76) were significantly more prevalent than in 2015. Furthermore, students who had received sex and STI/HIV prevention education and rated it as "good" (OR = 5.62, 95% CI: 2.72-11.64), who believed they could confidently refuse sex without a condom(OR = 1.95, 95% CI: 1.14-3.32), and who reported consistent condom use(OR = 2.27, 95% CI: 1.21-4.25) were also more prevalent in 2021. Use of contraception methods such as condoms(OR = 2.76, 95% CI: 1.50-5.09), the pill(OR = 2.42, 95% CI: 1.35-4.35), extracorporeal ejaculation (OR = 1.77, 95% CI:1.02-3.09), and the safe period(OR = 2.22, 95% CI: 1.22-4.04) also increased significantly. However, the proportion of students who had their first sexual relationship with a non-regular partner decreased(OR = 0.47, 95% CI: 0.24-0.93). Conclusion:The participants' knowledge of safe sex and sexual behaviour improveed between the two surveys. However, these positive changes have not had a significant enough impact to prevent STIs/HIV transmission and reduce pregnancy. Further efforts are needed to ensure that these changes lead to effective STIs/HIV prevention and reduction among students.

The mammalian intestine is a major site of colonization and a starting point of severe infections by Klebsiella pneumoniae. Inflammatory bowel disease (IBD) is an inflammatory disorder of the gut, and host-derived nitrate in IBD confers a luminal growth advantage upon Escherichia coli and Salmonella typhimurium through nitrate respiration in the inflamed gut. However, the impact of nitrate on the growth and pathogenicity of K. pneumoniae in this microenvironment is poorly understood. In this study, we used oral administration of dextran sodium sulphate to induce IBD in mouse models. We then analysed the colonization levels of K. pneumoniae wild-type (WT), the nitrate reductase gene mutant strains (ΔnarG, ΔnarZ and ΔnarGΔnarZ), and the molybdate uptake gene mutant strain (ΔmodA) in the inflamed intestinal tract. Results showed that the growth, intestinal colonization, and extraintestinal dissemination of K. pneumoniae were increased in the intestines of dextran sulphate sodium (DSS)-treated mice. Nitrate in the inflamed bowel conferred a growth advantage to K. pneumoniae through nitrate respiration. The molybdate transport protein ModA regulated nitrate reductase activity to increase the growth, intestinal colonization, and extraintestinal dissemination of K. pneumoniae. Tungstate will be a promising antibacterial agent to tackle K. pneumoniae infections in IBD patients.

In the following study, power allocation in underwater cooperative communication systems was investigated using game theory. To balance the energy consumption of nodes, extend their lifespan, and improve communication quality, a Stackelberg power control algorithm based on a non-uniform pricing mechanism was proposed. The interaction model between the transmitting and relay nodes was constructed as a two-layer Stackelberg game, which consisted of leaders and followers. The transmitting node acts as the leader, with its objective function comprising its transmission cost and the purchasing transmission power cost of the relay nodes. The relay nodes act as followers, with their objective function comprising revenue from selling power and their transmission cost. In addition, the remaining energy is incorporated into the objective function to balance the energy consumption of the nodes. Our simulation results indicate that, compared with algorithms that do not consider remaining energy, this algorithm improves the communication quality of the cooperative system and extends the network’s lifetime.

Background:Men who have sex with men (MSM) constitute a significant proportion of individuals living with human immunodeficiency virus. Over the past few years, China has implemented various strategies aimed at increasing the rate of HIV testing and reducing HIV transmission among MSM. Among these, the disclosure of HIV serostatus is an effective prevention strategy. Objective:This study aimed to assess HIV serostatus disclosure and identify factors associated with awareness of sexual partners' HIV status among MSM to provide a scientific basis for promoting HIV testing and reducing HIV transmission. Methods:A cross-sectional study based on a large-scale web-based survey was conducted among MSM in Zhejiang province, China, between July and December 2023. MSM who were HIV-negative or had an unknown HIV status were recruited from the Sunshine Test, a web-based platform that uses location-based services to provide HIV prevention services. Participants were required to complete a questionnaire on demographic characteristics, sexual behavior, rush popper use, awareness of sexual partners' HIV status, and knowledge of pre-exposure prophylaxis (PrEP) and postexposure prophylaxis (PEP). A multinomial regression model was used to identify the factors associated with awareness of sexual partners' HIV status. Results:A total of 7629 MSM participated in the study, with 45.2% (n=3451) being aware, 35.4% (n=2701) being partially aware, and 19.4% (n=1477) being unaware of their sexual partner's HIV status. The multinomial logistic regression analysis revealed the following results. Compared to those who were unaware of their sexual partner's HIV status, participants who were students (adjusted odds ratio [aOR] 1.43, 95% CI 1.09-1.86), had a monthly income of more than US $1400 (aOR 1.36, 95% CI 1.03-1.80), had insertive anal sex (aOR 1.35, 95% CI 1.12-1.63), had only male sexual partners (aOR 1.53, 95% CI 1.28-1.82), had 1 sexual partner in the past 3 months (aOR 2.36, 95% CI 2.01-2.77), had used condoms for the past 3 months (aOR 1.72, 95% CI 1.33-2.22), had frequently used rush poppers in the past 3 months (aOR 2.27, 95% CI 1.81-2.86), were aware of HIV PrEP (aOR 2.04, 95% CI 1.68-2.48), were aware of HIV PEP (aOR 1.69, 95% CI 1.39-2.06), used mail reagent self-testing (aOR 1.19, 95% CI 1.04-1.36), and had previously undergone HIV testing (aOR 1.40, 95% CI 1.16-1.69) were associated with increased odds of being aware of their sexual partner's HIV status. Conclusions:Overall, 45.2% of MSM who were HIV-negative or had an unknown status were aware of their sexual partners' HIV status in China. We suggest strengthening targeted interventions through web-based platforms and gay apps to promote the disclosure of HIV serostatus and reduce HIV transmission among MSM.

Objectives The characteristics of men who have sex with men (either exclusively or with both men and women; MSM) who engaged in casual sex among Chinese male university students have not been compared with the characteristics of men who have sex with only women (MSW). This information is important for tailoring targeted behavioral interventions to prevent human immunodeficiency virus (HIV)/sexually transmitted infection (STI) transmission in this subgroup of MSM. Methods Data were derived from a large cross-sectional electronic questionnaire survey conducted at 13 universities in Zhejiang Province, China, in 2018. Bivariate analyses were used to compare demographic, HIV-related psychosocial, and behavioral characteristics between MSM and MSW students who engaged in casual sex during the previous year. Proportion differences between the two groups and their 95% confidence intervals were analyzed. Results Among the 583 sexually active male students who engaged in casual sex during the previous year, 128 and 455 were MSM and MSW, respectively. Compared with MSW students, larger proportions of MSM students reported knowing that male-to-male sexual behavior was the main mode of HIV transmission among Chinese students (62.5% vs. 45.5%), consenting to commercial sex (67.2% vs. 53.4%), wanting to know the HIV serostatus of partners before casual sex (65.8% vs. 51.3%), feeling at risk of HIV infection (40.5% vs. 11.8%), high condom-decision scale scores (55.3% vs. 42.6%), engaging in sex with ≥ 5 casual sex partners (44.6% vs. 25.9%), searching for casual partners online (89.2% vs. 51.3%), consuming alcohol before casual sex (64.8% vs. 45.0%), engaging in sex with regular partners (83.1% vs. 67.0%), engaging in commercial sex (54.2% vs. 26.4%), and visiting a clinic for voluntary counselling and testing (VCT) (16.4% vs. 8.4%). However, compared with MSW students, smaller proportions of MSM students reported knowing that consistent condom use could prevent HIV transmission (80.5% vs. 95.2%) and that VCT should be actively sought after risky sexual behavior (78.9% vs. 93.8%), using condoms sometimes/often (26.4% vs. 44.3%), and consistently using condoms (28.9% vs. 40.1%) while engaging in sex with casual partners. Conclusions MSM students who engaged in casual sex were at a greater risk of HIV/STI transmission, compared with MSW students. Comprehensive interventions to address the risks of unprotected male-to-male sex, searching for casual sex partners online, and non-use of HIV testing services are needed to reduce the burden of HIV/STI transmission among this subgroup of MSM.

The scattering and absorption of light lead to color distortion and blurred details in the captured underwater images. Although underwater image enhancement algorithms have made significant breakthroughs in recent years, enhancing the effectiveness and robustness of underwater degraded images is still a challenging task. To improve the quality of underwater images, we propose a combined multi-attention mechanism and recurrent residual convolutional U-Net (ACU-Net) for underwater image enhancement. First, we add a dual-attention mechanism and convolution module to the U-Net encoder. It can unequally extract features in different channels and spaces and make the extracted image feature information more accurate. Second, we add an attention gate module and recurrent residual convolution module to the U-Net decoder. It helps extract features fully and facilitates the recovery of more detailed information when the image is generated. Finally, we test the subjective results and objective evaluation of our proposed algorithm on synthetic and real datasets. The experimental results show that the robustness of our algorithm outperforms the other five classical algorithms, such as in enhancing underwater images with different color shifts and turbidity. Moreover, it corrects the color bias and improves the contrast and detailed texture of the images.

Aims: This study aims to investigate the factors associated with sexual initiation among male vocational high school students (MVHSS) in Zhejiang Province, and provide a scientific basis for preventing unsafe sexual behavior and sexual health issues among adolescents. Background: The prevalence of sexual behavior among young students has risen significantly in recent years. Contracting HIV poses a serious physical and psychological burden on young individuals and their families. Thus, it is imperative to promptly and effectively address the spread of HIV among young people. Objective: The objectives of this study are to investigate the demographic characteristics of male vocational high school students (MVHSS) who have engaged in sexual activity and to identify associated factors, such as sexual attitudes and lifestyle, that may influence sexual initiation among this population, and to offer recommendations for interventions and policy development aimed at promoting healthy sexual behaviors among MVHSS. Methods: A survey was conducted among vocational high school students in grades one and two in Zhejiang Province. Variables that were statistically significantly associated with sexual initiation in bivariate analyses were included in a multivariate logistic regression model, which adopted a backward elimination procedure with a p-value > 0.10 as the exclusion criterion. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to describe the relationship between dependent and outcome variables. Results: Of the 1032 male participants, 17.4% had initiated sexual behavior. The multivariate analysis results indicated thatThose who were frequent smokers (adjusted OR[AOR] =4.89, 95% CI: 2.36–10.13), those who reported having been in love (AOR=2.86, 95% CI: 1.84–4.44), those currently in love (AOR=4.47, 95% CI: 2.68–7.45), those willing to have sex with a high school student (AOR =2.63, 95% CI: 3.31–6.50), those willing to pay for sex (AOR =1.90, 95% CI: 1.10–3.27), and those who had received sex education and STDs/AIDS prevention education in school (AOR =2.21, 95% CI: 1.53–3.18) were more likely to initiate sexual behavior. Conclusion: Sexual attitudes among MVHSS are liberal, and the prevalence of sexual initiation is high. Interventions targeted at improving sexual safety education, reducing the rate of early initiation of sexual behavior, and promoting condom use among students must be implemented to reduce the risk of HIV infections and STDs among sexually active MVHSS.

Hemodialysis membranes play an important role in the treatment of renal failure, but their anticoagulant and antioxidant properties need to be improved to prevent membrane fouling and oxidative stress in dialysis. To these ends, a heparinoid gel incorporating carbon dots (CDs) was applied to modify polyethersulfone hemodialysis membranes. The CDs were mixed with ammonium persulfate, Sodium p-styrene sulfonate, and N, N Methylenebisacrylamide monomers, and modified to surfaces of hemodialysis membranes through the in-situ polymerization of these monomers. As prepared hybrid hydrogel featured a high free radical scavenging rate and anticoagulant time for the hemodialysis membrane. The scavenging rates of the modified membrane for 2, 2diphenyl-1-picrylhydrazyl (DPPH) and 2, 2 '-azinobis-(3-ethylbenzthiazoline-6-sulphonate (ABTS+) free radicals are as high as 74.01% and 97.78%. The activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT) of the dialysis membrane are 600 s,283 s and 348 s, respectively.

Background: Men who have sex with men (MSM) constitute a significant population of patients infected with HIV. In recentyears, several efforts have been made to promote HIV testing among MSM in China. Objective: This study aimed to assess HIV testing coverage and factors associated with first-time HIV testing among MSM toprovide a scientific basis for achieving the goal of diagnosing 95% of patients infected with HIV by 2030. Methods: This cross-sectional study was conducted between July 2023 and December 2023. MSM were recruited from the"Sunshine Test," an internet platform that uses location-based services to offer free HIV testing services to MSM by visiting theWeChat official account in Zhejiang Province, China. Participants were required to complete a questionnaire on their demographiccharacteristics, sexual behaviors, substance use, and HIV testing history. A logistic regression model was used to analyze first-timeHIV testing and its associated factors. Results: A total of 7629 MSM participated in the study, with 87.1% (6647) having undergone HIV testing before and 12.9%(982) undergoing HIV testing for the first time. Multivariate logistic regression analysis revealed that first-time HIV testing wasassociated with younger age (adjusted odds ratio [aOR] 2.55, 95% CI 1.91-3.42), lower education (aOR 1.39, 95% CI 1.03-1.88),student status (aOR 1.35, 95% CI 1.04-1.75), low income (aOR 1.55, 95% CI 1.16-2.08), insertive anal sex role (aOR 1.28, 95%CI 1.05-1.56), bisexuality (aOR 1.69, 95% CI 1.40-2.03), fewer sex partners (aOR 1.44, 95% CI 1.13-1.83), use of rush poppers(aOR 2.06, 95% CI 1.70-2.49), unknown HIV status of sex partners (aOR 1.40, 95% CI 1.17-1.69), lack of awareness of HIVpre-exposure prophylaxis (aOR 1.39, 95% CI 1.03-1.88), and offline HIV testing uptake (aOR 2.08, 95% CI 1.80-2.41). Conclusions: A notable 12.9% (982/7629) of MSM had never undergone HIV testing before this large internet survey. Werecommend enhancing HIV intervention and testing through internet-based platforms and gay apps to promote testing amongMSM and achieve the target of diagnosing 95% of patients infected with HIV by 2030.

This study aimed to analyze the characteristics and risk factors associated with casual sexual behavior among sexually active college students and to contribute to AIDS prevention and control efforts among this demographic. A cross-sectional survey was conducted using a stratified cluster sampling technique. Self-reported sexually active college students were selected as respondents from 11 cities in Zhejiang Province from October 8 to November 30, 2018. A questionnaire was used to collect variables such as demographic information, sexual attitudes, intervention acceptance, and self-efficacy of condom use. Univariate and multivariate analyses were performed. Among 3,771 college students who reported engaging in sexual activity, 675 (17.90%) reported engaging in casual sexual encounters. The multivariate analysis revealed multiple factors associated with casual sexual behavior among students: being male, originating from a city/town, having pursued HIV testing education in the last year, seeking HIV risk self-assessment within the last year, accepting to engage in one-night stand behavior, accepting to partake in commercial sexual activity, having conducted HIV antibody tests within the last year, homosexual partner or homosexual/heterosexual partner, demonstrating self-efficacy in condom usage, and monthly living expenses falling within the range of 1001-1500 yuan. Additionally, students with knowledge that appearance does not determine HIV infection, a proclivity for seeking HIV counseling and testing following high-risk sexual behavior and awareness that the centers for disease control provides HIV diagnosis were found to have significant associations with casual sexual activity. Casual sex is significantly prevalent among college students, with male, students from urban areas, those who accepted to engage in one-night stand behavior and partook in commercial sexual activity demonstrating a higher propensity for such behavior. This tendency can be attributed to several factors including a more liberal sexual attitude, a rudimentary understanding of HIV risk, and a low adoption rate of HIV testing. Therefore, it is imperative to enhance HIV prevention and education among college students.

As a potential vectored vaccine, Newcastle disease virus (NDV) has been subject to various studies for vaccine development, while relatively little research has outlined the immunomodulatory effect of the virus in antigen presentation. To elucidate the key inhibitory factor in regulating the interaction of infected dendritic cells (DCs) and T cells, DCs were pretreated with the NDV vaccine strain LaSota as an inhibitor and stimulated with lipopolysaccharide (LPS) for further detection by enzyme-linked immunosorbent assay (ELISA), flow cytometry, immunoblotting, and quantitative real-time polymerase chain reaction (qRT-PCR). The results revealed that NDV infection resulted in the inhibition of interleukin (IL)-12p40 in DCs through a p38 mitogen-activated protein kinase (MAPK)-dependent manner, thus inhibiting the synthesis of IL-12p70, leading to the reduction in T cell proliferation and the secretion of interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and IL-6 induced by DCs. Consequently, downregulated cytokines accelerated the infection and viral transmission from DCs to T cells. Furthermore, several other strains of NDV also exhibited inhibitory activity. The current study reveals that NDV can modulate the intensity of the innate–adaptive immune cell crosstalk critically toward viral invasion improvement, highlighting a novel mechanism of virus-induced immunosuppression and providing new perspectives on the improvement of NDV-vectored vaccine.