A diode laser with a rectangular spot was used to perform laser surface treatment on a 1.0C‐1.5Cr steel. Based on the numerical simulation, an empirical equation was developed to predict the peak ...temperature, and the microstructure distribution was analyzed. The bearing capacity and impact fracture mechanisms were also studied. The results indicated that the relationship between the peak temperature and scanning rate was affected by the depth, and the peak temperature on the outer surface was approximately linear with the reciprocal of the square root of the scanning rate. The higher peak temperature leads to cementite dissolution and coarsening near the outer surface. Cementite dissolution was postponed during the laser surface treatment. The bearing capacity was a combined result of strengthening in the surface region and softening in the heat affect zone. Under a lighter contact load, laser surface treatment had no adverse effect on the bearing capacity. However, under a heavier contact load, the plastic deformation of the heat affect zone slightly decreased the bearing capacity. The impact fracture started at the outer surface of the laser-hardened layer, and propagated intergranularly near the crack source, and then propagated inward through the transgranular fracture. Owing to the stress concentration near the interface between the cementite and martensite matrix, cementite particles tend to appear along the crack propagation path. The decrease in the impact absorbed energy is attributed to the brittleness of the hardened layer and tensile residual stress, and the impact toughness can be improved by preheating.
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•Higher peak temperature tends to result in the cementite coarsening.•An empirical equation was developed to predict the peak temperature distribution.•Stress concentration appears near the interface of cementite under extra load.•Laser hardening will not decrease the bearing capacity under lighter contact load.•Brittle surface hardened layer and residual tensile stress decline the toughness.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
HIV self-testing (HIVST) offers potential solutions to challenges associated with site-based HIV testing (SBHT). However, the effectiveness of HIVST as an HIV prevention strategy for men who have sex ...with men (MSM) discontinuing pre-exposure prophylaxis (PrEP) after the completion of PrEP demonstration project has rarely been assessed.
The China Real-world Study of Oral PrEP (CROPrEP) project was conducted in four cities in China. Participants were directed to community resources to continue their PrEP medication after the discontinuation of project-provided PrEP at the last CROPrEP visit. We conducted a multicentre open-label randomized controlled trial among MSM who had discontinued PrEP induced by the completion of CROPrEP. Eligible participants were randomly assigned to either the intervention group or the control group (1:1). Participants received regular health education and behavioural interventions throughout the trial. The intervention group was given a link to order free HIVST kits online, while the control group received information about free SBHT. Both groups completed internet-based follow-up surveys at three and six months. The primary outcome was the proportion of participants who underwent HIV testing during the six-month follow-up period. This trial was registered at chictr.org.cn (ChiCTR2000038416).
Between November 2020 and January 2021, we recruited a total of 620 participants (300 in the intervention group and 320 in the control group). The follow-up completion rates were 99·0% and 95·0% in the intervention and control groups, respectively. At baseline, the median age of participants was 32 (interquartile range: 26–37), and 77·7% underwent HIV testing in the past three months. The proportion of participants who underwent HIV testing in the past three months was higher in the intervention group than in the control group at both the three-month (adjusted risk difference RD: 36·7, 95% confidence interval CI: 35·1–38·5, p < 0·001) and six-month (RD: 26·7, 95% CI: 24·6–28·7 p < 0·001) follow-up periods.
Our study suggests that providing online distribution of HIVST kits for MSM with PrEP discontinuation induced by completion of the PrEP project effectively promoted HIV testing. This digital approach improves access to HIV testing for MSM and can be applicable to other settings where MSM turn to online public health services.
The study was funded by the Fund of National Natural Science Foundation of China; the Mega-Projects of National Science Research for the 13th Five-Year Plan; and the Liaoning Revitalization Talents Program, China.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Persistent activation and inflammation impair immune response and trigger disease progression in HIV infection. Emerging evidence supports the supposition that excessive production of ...interferon-inducible protein 10 (IP-10), a critical inflammatory cytokine, leads to immune dysfunction and disease progression in HIV infection. In this study, we sought to elucidate the cause of the upregulated production of IP-10 in HIV infection and explore the underlying mechanisms. Bolstering miR-21 levels using mimics resulted in the obvious suppression of lipopolysaccharide (LPS)-induced IP-10 in monocyte leukemia cells THP-1 and vice versa. The analysis of the primary monocytes of HIV patients revealed significantly less miR-21 than in healthy controls; this was opposite to the tendency of IP-10 levels in plasma. The secretion of IP-10 due to LPS stimulation was not affected by miR-21 modulation in the differentiated THP-1 macrophages (THP-1-MA). We found a novel switch, IFN-stimulated gene 15 (
), which triggers the expression of IP-10 and is significantly upregulated during the differentiation of THP-1 into THP-1-MA. The inhibition of ISG15 can restore the regulation of IP-10 by miR-21. In summary, IP-10 expression in monocytes is regulated by miR-21, whereas in macrophages, this fine-tuning is attenuated by the enhanced expression of ISG15. This study paves the way to a comprehensive understanding of the molecular regulatory mechanism of IP-10, a key point in immune intervention strategy.
No randomized controlled trials have involved established HIV-diagnosed men who have sex with men (MSM) diagnosed for more than 6 months into the assisted partner service (aPS). We compared voluntary ...aPS involving community-based organizations (CBOs) and HIV self-testing (aPSST) with regular partner service (rPS) in HIV-diagnosed MSM irrespective of diagnosis time.
In this unblinded, multicentre trial, we enrolled HIV-diagnosed MSM irrespective of diagnosis time in three cities in northern China. Index patients were randomly assigned to aPSST or rPS. Index patients in the aPSST group were additionally provided a comprehensive intervention package including HIV self-testing and CBO-based aPS compared with rPS group. The primary outcome was the number of index patients whose any sexual partner tested for HIV during the 6-month study. Completion of HIV testing was defined as sexual partners taking a clinic-based HIV test or HIV self-testing. Safety was assessed preliminary at the end of the 6-month follow-up. This study has been registered at chictr.org.cn (ChiCTR2000038784).
From March to December 2021, 325 of HIV-diagnosed MSM were enrolled (90⋅2% were established HIV-diagnosed MSM) and randomly assigned to receive aPSST (n = 167) or rPS (n = 158). At 6 months, 110 (65⋅9%) index patients in the aPSST group had at least one sexual partner tested for HIV compared with 50 (31⋅6%) in the rPS group (hazard ratio 2⋅86; 95% confidence interval 2⋅03–4⋅03; p < 0⋅001). No significant difference was observed in effects of aPSST on HIV testing promotion between established and newly HIV-diagnosed MSM. Self-reported harms were infrequently observed in both groups (approximately 2⋅0%).
Among HIV-diagnosed MSM regardless of diagnosis time, voluntary aPS involving CBOs and HIV self-testing was effective and safe for promoting partner HIV testing.
This work was supported by the Mega-Projects of National Science Research, the National Natural Science Foundation of China and the Liaoning Revitalization Talents Program, China.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
China has the largest number of the elderly in the world. As the proportion of elderly is rapidly increasing among national reported HIV/AIDS cases, it is a concern about HIV epidemic among older MSM ...in China. However, studies on HIV prevalence and unprotected anal intercourse (UAI) among Chinese older MSM were relatively few or generally had small sample sizes.
English and Chinese articles published in peer-reviewed journals were identified by systematically searching 5 electronic databases including PubMed and through cross-referencing. Summary prevalence rates of HIV infection and UAI with male sexual partners were calculated, and analyses were performed using the software Comprehensive Meta-Analysis V2.0 and SPSS V17.0. Subgroup analyses were performed separately by sample size, study year, study location, recruitment settings and sampling method.
Twenty eligible cross-sectional studies (3 in English and 17 in Chinese), published between 2005 and 2013, with a total of 2812 older MSM participants, were identified. Our meta-analyses showed that the prevalence of HIV, syphilis and UAI in the last 6 months were 11.6% (95% confidence interval CI: 8.0%-16.6%), 23.0% (95% CI: 15.8%-32.3%) and 79.5% (95% CI: 72.7%-84.9%), respectively. HIV prevalence increased over the study period (6.3% in 2003-2007; 8.6% in 2008-2009, and 11.5% in 2010-2011, trend test Chi-square = 7.02, p = 0.008). The pooled prevalence of HIV (11.6% vs. 5.2%, Chi-square value = 36.2, p < 0.001) and UAI (79.5% vs. 52.6%, Chi-square value = 440.04, p < 0.001) among older MSM were both significantly higher than among younger age group (age < 50 years).
Older Chinese MSM have high prevalence of HIV and syphilis. Unprotected anal sex is common and further puts them at high risks of acquiring and transmitting HIV, which was one of reasons for the rapid increasing of national reported older male HIV/AIDS cases. Prevention intervention programs should be specially tailored for this high risk MSM subgroup.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Purpose. To explore the association between differential Tim-3 and PD-1 expression patterns and HIV disease progression, and to investigate the impact of common γ-chain cytokines on Tim-3 and PD-1 ...expression patterns on T cells. Methods. Tim-3/PD-1 expression on the T cells of patients with early and chronic HIV infections was detected. The expression levels and functional profiles of T cells with differential Tim-3 and PD-1 expression patterns induced by γ-chain cytokines were studied. Results. The elevation of differential Tim-3 and PD-1 expression patterns on T cells appeared early in HIV infection. Co-expression of Tim-3 and PD-1 (Tim-3+PD-1+) correlates with more severe exhaustion of T cells during HIV infection. In vitro stimulation of common γ-chain cytokines can induce differential expression patterns of Tim-3 and PD-1 on T cells. The enhancement of Tim-3 and PD-1 expression by common γ-chain IL-2 can inhibit the function of T cells re-stimulated by HIV gag and TCR, not by the re-stimulation of IL-2. Conclusions. The elevation of differential Tim-3 and PD-1 expression patterns on T cells represents a state of T cell exhaustion and can be induced by common γ-chain cytokines. These findings provide insights into HIV pathogenesis and help inform immune intervention strategies.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
Several lines of evidence suggest that slow coronary flow (SCF) phenomenon seems to be an early form of atherosclerosis and low-grade inflammation plays a role in the development of SCF. ...Interleukin-6 (IL-6) is a pleiotropic cytokine, functions as a mediator of inflammatory response, and has both pro-inflammatory and anti-inflammatory properties. The aim of the present study is to investigate the relationship between IL-6 -634C/G polymorphism and SCF in Han Chinese.
250 subjects who underwent coronary angiography and had normal coronary arteries of varying coronary flow rates without any atherosclerotic lesion were enrolled in this study. 41 patients who had thrombolysis in myocardial infarction frame counts (TFC) above the normal cutoffs were considered to have SCF and 209 subjects within normal limits served as normal coronary flow (NCF) group. The PCR-based restriction fragment length polymorphism (PCR-RFLP) technique was used to assess the genotypes.
The distribution of the IL-6 -634C/G genotypes (CC, CG, and GG) was 56.94%, 37.80%, and 5.26% in the NCF subjects, and 36.59%, 48.78%, and 14.63% in the SCF group, respectively (p = 0.0173). The frequency of the G allele in the SCF (39.02%) group was significantly higher than that in the NCF (24.16%) group (p = 0.0054). Compared with the CC genotype, the G allele carriers (CG + GG genotypes) had increased risk of SCF in both unadjusted and adjusted analyses. In SCF patients, the average serum IL-6 levels (pg/mL) in CG + GG genotype (4.78 ± 0.42) were statistically higher than in CC genotype (3.93 ± 0.36) (p = 0.0000).
Our data support that IL-6 -634C/G polymorphism is associated with SCF and the G allele has increased risk for SCF in Han Chinese.
Exposure to heat stress causes diminished work performance and leads to economic loss. In the last two decades, China has experienced both rapid economic development and environmental warming; ...however, the spatiotemporal variations of association between environmental heat and labor loss have been rarely investigated behind this double impact. Here, we evaluated the variation in China's heat-induced labor productivity loss and related economic cost from 2001 to 2019 and investigated the effect of economic development and regional warming. We found that decline in labor productivity because of heat stress increased significantly (p < 0.05 for heavy-intensity work), and the corresponding economic loss also exhibited a drastic increase by 6- to 9-fold. The relative economic loss showed a slight but nonsignificant increase with an average value of 0.54% of the annual total earnings. At the sub-regional and sectoral level, adverse effects were more prominent in the southeast region, and the secondary industry sectors, such as construction and manufacturing, contributed to larger proportions of economic losses. The transformation of industrial structure made economic sectors more vulnerable to heat exposure, and increasingly preventive effects of air-conditioning use were noted on economic damage due to heat-induced productivity decline (36.0% relative economic benefits in 2019 compared to 9.7% in 2001). Our findings could provide a deep insight into heat burden on occupational health and heat adaptation strategies regionally under climate change, especially in developing areas with higher temperature and humidity environment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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