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Two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDCs) are extensively employed as channel materials in advanced electronic devices. The electrical contacts between electrodes and 2D semiconductors play a crucial role in the development of high-performance transistors. While numerous strategies for electrode interface engineering have been proposed to enhance the performance of n-type 2D transistors, upgrading p-type ones in a similar manner remains a challenge. In this work, significant improvements in a p-type WSe2 transistor are demonstrated by utilizing metallic MoO2 nanosheets as the electrode contact, which are controllably fabricated through physical vapor deposition and subsequent annealing. The MoO2 nanosheets exhibit an exceptional electrical conductivity of 8.4 × 104 S mâ1 and a breakdown current density of 3.3 × 106 A cmâ2. The work function of MoO2 nanosheets is determined to be ≈5.1 eV, making them suitable for contacting p-type 2D semiconductors. Employing MoO2 nanosheets as the electrode contact in WSe2 transistors results in a notable increase in the field-effect mobility to 92.0 cm2 Vâ1 sâ1, which is one order of magnitude higher than the counterpart devices with conventional electrodes. This study not only introduces an intriguing 2D metal oxide to improve the electrical contact in p-type 2D transistors, but also offers an effective approach to fabricating all-2D devices.
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As functional materials and nano-catalysts, Pd nanoparticles (NPs) are often used to modify two-dimensional (2D) materials. In the heterostructures of metal NPs and 2D transition metal dichalcogenides, the interface atomic configuration and interface effect greatly affect material properties and stability. Therefore, the rational design of interface structures and in-depth analysis of interface interactions are of vital importance for the preparation of specific functional devices. In this work, Pd NPs were deposited on mechanically exfoliated MoS2 flakes and the epitaxial relationship between Pd and MoS2 was observed, accompanied by distinct moiré patterns. Raman spectra of the Pd NPs/MoS2 heterostructure showed an E12g' vibration mode indicative of the local strain in MoS2. A new vibration mode A'1g appeared in the higher-frequency direction compared with the pristine A1g peak. Combined with X-ray photoelectron spectra and density functional theory calculations, the new vibration mode can be attributed to the bonding between Pd and MoS2. Besides, graphene was inserted between Pd NPs and MoS2, and the decoupling of the interfacial effect by graphene was investigated. This study will help deepen our understanding on the interaction mechanism between metals and MoS2, thereby enabling the modulation of optoelectronic properties and the performance of these hybrid materials.
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Epitaxial growth stands as a key method for integrating semiconductors into heterostructures, offering a potent avenue to explore the electronic and optoelectronic characteristics of cutting-edge materials, such as transition metal dichalcogenide (TMD) and perovskites. Nevertheless, the layer-by-layer growth atop TMD materials confronts a substantial energy barrier, impeding the adsorption and nucleation of perovskite atoms on the 2D surface. Here, we epitaxially grown an inorganic lead-free perovskite on TMD and formed van der Waals (vdW) heterojunctions. Our work employs a monomolecular membrane-assisted growth strategy that reduces the contact angle and simultaneously diminishing the energy barrier for Cs3Sb2Br9 surface nucleation. By controlling the nucleation temperature, we achieved a reduction in the thickness of the Cs3Sb2Br9 epitaxial layer from 30 to approximately 4 nm. In the realm of inorganic lead-free perovskite and TMD heterojunctions, we observed long-lived interlayer exciton of 9.9 ns, approximately 36 times longer than the intralayer exciton lifetime, which benefited from the excellent interlayer coupling brought by direct epitaxial growth. Our research introduces a monomolecular membrane-assisted growth strategy that expands the diversity of materials attainable through vdW epitaxial growth, potentially contributing to future applications in optoelectronics involving heterojunctions.
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In this study, a novel Ag-loaded 4 Å zeolite was synthesized through the combined action of strong ultrasound and a high-voltage electrostatic field (the Z-Ag-UE) and its catalytic activity was evaluated in the epoxidation of styrene. The prepared catalysts were characterized using XRD, SEM, XPS, BET, TG, ICP-OES. The results showed that the silver evenly dispersed inside the octahedral 4 Å zeolite structure rather than being attached to the surface of the material like in the impregnation method, and this Ag-loaded 4 Å zeolite had a high surface area, uniform particle size distribution, and excellent high temperature thermal stability. The catalytic performance of the Ag-loaded 4 Å zeolite was investigated by varying the reaction conditions such as the amount of catalyst, temperature, and reaction time. Under optimized conditions, the Ag-loaded 4 Å zeolite showed high selectivity and conversion for the epoxidation of styrene, achieving a conversion rate of up to 98% and a selectivity of 94%. In particular, the catalyst had excellent recyclability and was reused more than fifteen times with the catalytic performance remaining unchanged. This method of loading metal prepared under external field conditions provides a new method and idea for future research in related fields.
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BACKGROUND: Observational studies suggest that voluntary medical male circumcision (VMMC) may lower HIV risk among men who have sex with men (MSM). A randomized controlled trial (RCT) is needed to confirm this. OBJECTIVE: To assess the efficacy of VMMC in preventing incident HIV infection among MSM. DESIGN: An RCT with up to 12 months of follow-up. (Chinese Clinical Trial Registry: ChiCTR2000039436). SETTING: 8 cities in China. PARTICIPANTS: Uncircumcised, HIV-seronegative men aged 18 to 49 years who self-reported predominantly practicing insertive anal intercourse and had 2 or more male sex partners in the past 6 months. INTERVENTION: VMMC. MEASUREMENTS: Rapid testing for HIV was done at baseline and at 3, 6, 9, and 12 months. Behavioral questionnaires and other tests for sexually transmitted infections were done at baseline, 6 months, and 12 months. The primary outcome was HIV seroconversion using an intention-to-treat analysis. RESULTS: The study enrolled 124 men in the intervention group and 123 in the control group, who contributed 120.7 and 123.1 person-years of observation, respectively. There were 0 seroconversions in the intervention group (0 infections [95% CI, 0.0 to 3.1 infections] per 100 person-years) and 5 seroconversions in the control group (4.1 infections [CI, 1.3 to 9.5 infections] per 100 person-years). The HIV hazard ratio was 0.09 (CI, 0.00 to 0.81; P = 0.029), and the HIV incidence was lower in the intervention group (log-rank P = 0.025). The incidence rates of syphilis, herpes simplex virus type 2, and penile human papillomavirus were not statistically significantly different between the 2 groups. There was no evidence of HIV risk compensation. LIMITATION: Few HIV seroconversions and limited follow-up period. CONCLUSION: Among MSM who predominantly practice insertive anal intercourse, VMMC is efficacious in preventing incident HIV infection; MSM should be included in VMMC guidelines. PRIMARY FUNDING SOURCE: The National Science and Technology Major Project of China.
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Circuncisão Masculina , Infecções por HIV , Homossexualidade Masculina , Humanos , Masculino , Adulto , Infecções por HIV/prevenção & controle , Infecções por HIV/epidemiologia , Adulto Jovem , Adolescente , Pessoa de Meia-Idade , China/epidemiologia , Incidência , Comportamento Sexual , Análise de Intenção de TratamentoRESUMO
The uptake of COVID-19 booster vaccination among older adults in China is suboptimal. Here, we report the results of a parallel-group cluster-randomized controlled trial evaluating the efficacy of promoting COVID-19 booster vaccination among grandparents (≥60 years) through a health education intervention delivered to their grandchildren (aged ≥16 years) in a Chinese cohort (Chinese Clinical Trial Registry: ChiCTR2200063240 ). The primary outcome was the uptake rate of COVID-19 booster dose among grandparents. Secondary outcomes include grandparents' attitude and intention to get a COVID-19 booster dose. A total of 202 college students were randomized 1:1 to either the intervention arm of web-based health education and 14 daily reminders (n = 188 grandparents) or control arm (n = 187 grandparents) and reported their grandparents' COVID-19 booster vaccination status at baseline and 21 days. Grandparents in the intervention arm were more likely to receive COVID-19 booster vaccination compared to control cohort (intervention, 30.6%; control, 16.9%; risk ratio = 2.00 (95% CI, 1.09 to 3.66)). Grandparents in the intervention arm also had greater attitude change (ß = 0.28 (95% CI, 0.04 to 0.52)) and intention change (ß = 0.32 (95% CI, 0.12 to 0.52)) to receive a COVID-19 booster dose. Our results show that an educational intervention targeting college students increased COVID-19 booster vaccination uptake among grandparents in China.
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Vacinas contra COVID-19 , COVID-19 , Avós , Imunização Secundária , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , Masculino , Feminino , China , Vacinas contra COVID-19/administração & dosagem , Pessoa de Meia-Idade , Idoso , Avós/psicologia , Imunização Secundária/estatística & dados numéricos , SARS-CoV-2/imunologia , Vacinação/estatística & dados numéricos , Vacinação/psicologia , Educação em Saúde , Adolescente , Adulto Jovem , AdultoRESUMO
Objective: Sexual health plays a vital role in healthy aging. However, little is known about the sexual attitudes of and the utilization of sexual and reproductive health services by older women in China. This article is based on a qualitative study of older Chinese women in suburban areas to examine their attitudes toward sexuality and their utilization of sexual and reproductive health services. Methods: Face-to-face semi-structured interviews were conducted with older women (ages 50 to 74) from suburbs of southern China. Participants were purposively sampled on a convenience basis and recruited when they were visiting community health facilities between June and December 2021. Inclusion criteria were older women aged 50 years and older who had sexual experience. A topic guide was used that focused on sexual activity, sexual attitudes, the utilization of sexual and reproductive health services, and the factors that influence these. Interviews were audio recorded and transcribed verbatim. We coded the data inductively and conducted a thematic analysis. Results: Twenty-six Chinese women participated in the study. These older women had varying attitudes regarding sexual activity and its significance for older adults. The gender norms they held concerning sexual desire deemed that men had higher sexual desire than women. Most asymptomatic women did not actively seek sexual and reproductive health services. In most cases, women only sought professional services when they started to have sexual and reproductive health problems. Factors influencing the uptake of sexual and reproductive health services by older women were cost (affordability), availability, distance (accessibility), and conservative cultural norms towards sexuality. Conclusion: The attitudes of older women towards sexual activity are diverse. While some view sexual activity as common and essential for maintaining a sense of well-being in older age, others may hold different perspectives, considering it less significant. The utilization of sexual and reproductive health services by older Chinese women, except for when they were having a specific health issue, was low. Sexual health messages and services tailored for older women are needed.
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Serviços de Saúde Reprodutiva , Comportamento Sexual , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Saúde Reprodutiva , Conhecimentos, Atitudes e Prática em Saúde , ChinaRESUMO
INTRODUCTION: Treatment options for second-generation (2nd-gen) ALK tyrosine kinase inhibitor (TKI)-resistant patients are limited. We evaluated the safety, pharmacokinetics, and efficacy of ficonalkib (SY-3505), a third-generation (3rd-gen) ALK TKI, in patients with advanced ALK-positive non-small cell lung cancer. METHODS: This first-in-human, phase 1/2 study (Chinese Clinical Trial Registry identifier: ChiCTR1900025619; ClinicalTrials.gov identifier: NCT05257512) had two parts. Phase 1 included a dose-escalation phase (25-800 mg quaque die [QD]) and a dose-expansion phase (500 mg QD or 600 mg QD). Phase 2 enrolled patients treated at recommended phase 2 dose. Primary end points were safety in phase 1 and objective response rate (ORR) in phase 2. RESULTS: Between April 21, 2020, and August 31, 2023, a total of 127 patients with advanced ALK-positive non-small cell lung cancer were enrolled, with 62 in phase 1. Ficonalkib was well absorbed and tolerated, with one dose-limited toxicity event occurring at 800 mg QD. Treatment-related adverse events occurred in 85.5% of patients, with 19.4% experienced greater than or equal to grade 3 events. The ORR was 38.3% (23 of 60, 95% confidence interval [CI]: 26.1%-51.8%) in phase 1, and 600 mg QD was established as recommended phase 2 dose. In phase 2, a total of 65 patients received ficonalkib at 600 mg QD. In total, 88 patients received ficonalkib at 600 mg QD in phase 1/2, and all had received prior 2nd-gen ALK TKI treatment. Furthermore, 90.9% of the patients experienced treatment-related adverse events and 14.8% experienced greater than or equal to grade 3 events. The ORR in efficacy-assessable patients who received ficonalkib at 600 mg QD was 47.5% (38 of 80, 95% CI: 36.2%-59.0%), with an intracranial ORR of 37.5% (12 of 32, 95% CI: 21.1%-56.3%) in these patients with measurable brain lesions at baseline. CONCLUSIONS: Ficonalkib (SY-3505) was well tolerated, with favorable safety profiles and promising efficacy in patients resistant to prior 2nd-gen ALK TKI.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Masculino , Feminino , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Pessoa de Meia-Idade , Adulto , Idoso , Quinase do Linfoma Anaplásico/antagonistas & inibidores , Quinase do Linfoma Anaplásico/genética , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/administração & dosagemRESUMO
Background: During a vaccination plateau phase, traditional vaccination promotion strategies such as the mobilization of government and community appear to have limited impact on expanding the coverage. New strategies to promote vaccination are needed especially in older adults. Our study aimed to assess college students' intention to encourage coronavirus disease 2019 (COVID-19) vaccination among their grandparents and its correlates. Methods: A cross-sectional survey was conducted in China from May to June 2022. We collected information on socio-demographics of college students and their grandparents, constructs of health belief model (HBM) and theory of planned behavior (TPB) for college students, and college students' intention to encourage COVID-19 vaccination among their grandparents. Multilevel logistic regression models were performed to assess correlates of intention. Results: We enrolled 2681 college students who reported information for 6302 grandparents. 2272 students (84.7 %) intended to encourage COVID-19 vaccination for 4744 (75.3 %) grandparents. Intention was associated with having received a booster dose of COVID-19 vaccine (AOR 3.28, 95 % CI 1.68-6.42), having ever lived with their grandparents (2.07, 1.46-2.93), and having grandparents who regularly went outdoors (2.85, 1.70-4.76). HBM and TPB models showed that college students who had higher levels of perceived susceptibility (1.79, 1.12-2.87), perceived severity (1.52, 1.12-2.06) of COVID-19 among their grandparents, and higher levels of subjective norms (2.88, 1.61-5.15) were more likely to have the intention. Conclusion: College students' intention to encourage COVID-19 vaccination among their grandparents was high. It may be potentially viable to engage college students in promoting COVID-19 and other routine vaccination among older adults.
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The crystal growth kinetics is crucial for the controllable preparation and performance modulation of metal nanocrystals (NCs). However, the study of growth mechanisms is significantly limited by characterization techniques, and it is still challenging to in situ capture the growth process. Real-time and real-space imaging techniques at the atomic scale can promote the understanding of microdynamics for NC growth. Herein, the growth of Pd NCs on monolayer MoS2 under different atmospheres was in situ studied by environmental transmission electron microscopy. Introducing carbon monoxide can modulate the diffusion of Pd monomers, resulting in the epitaxial growth of Pd NCs with a uniform orientation. The electron energy loss spectroscopy and theoretical calculations showed that the CO adsorption assured the specific exposed facets and good uniformity of Pd NCs. The insight into the gas-solid interface interaction and the microscopic growth mechanism of NCs may shed light on the precise synthesis of NCs on two-dimensional (2D) materials.
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Ignition advance angle is one of the important factors affecting the performance of the engine, when it occurs abnormally will make the engine power and economy worse, and even cause serious damage to the engine. Therefore, it is very necessary to recognize the abnormal ignition advance angle of the engine. However, the engine system is closed and has a complex structure, which makes traditional diagnostic methods difficult. This paper proposes an intelligent identification method based on acoustic emission (AE) signals, which collects the AE signals from the engine surface and divides their spectra into equal parts, and selects the frequency bands with high contribution to the classification based on the minimum distance method to construct feature maps, which is used as the input to the convolutional neural network (CNN). The extracted frequency band features of this method can better characterize the AE signals, and the constructed feature maps make the fault information more obvious. Experiments show that the accuracy of this method for abnormal ignition advance angle under normal operating conditions of piston aero-engine is 100%, which is better than the traditional methods. In addition, the recognition accuracies under the other two operating conditions are 99.75% and 98.5%, respectively, indicating that the method has a certain universality.
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BACKGROUND: Kaposi sarcoma is a rare, possibly angioproliferative, tumour. Kaposi sarcoma is one of the most common cancers in people living with HIV and poses a serious public health challenge in regions with high HIV burden. We aim to describe global patterns and population-wide trends in the burden of Kaposi sarcoma. METHODS: In this population-based study, the incidence and mortality estimates of Kaposi sarcoma from 185 countries and regions in 2020 were extracted from the GLOBOCAN 2020 database. The time trends in Kaposi sarcoma incidence were evaluated using the cancer registry data from Cancer Incidence in Five Continents plus from 1998 to 2012. We did not apply any inclusion or exclusion criteria to the data used in this study. Joinpoint regression was used to evaluate the average annual percentage change (AAPC) to quantify trends in the age-standardised incidence rate (ASIR) of Kaposi sarcoma. Correlation analysis was used to evaluate the relationship between the ASIR or age-standardised mortality rate (ASMR) and Human Development Index (HDI). FINDINGS: In 2020, the global estimated ASIR of Kaposi sarcoma was 0·39 (per 100â000 people), with an estimated 34â270 newly diagnosed cases (23â413 males and 10â857 females). An estimated 15â086 Kaposi sarcoma deaths were reported (9929 males and 5157 females), corresponding to an ASMR of 0·18 (per 100â000 people). In 2020, Africa accounted for 73·0% (25â010 of 34â270) of the incidence and 86·6% (13â066 of 15â086) of the deaths from Kaposi sarcoma worldwide. There was a significant correlation between the ASIR or ASMR and HDI. The incidence of Kaposi sarcoma increased in males in both Türkiye and the Netherlands. The AAPC was 11·5% (95% CI 3·2-20·4) for males in Türkiye and 2·5% (1·1-3·9) for males in the Netherlands from 1998 to 2012. The incidence of Kaposi sarcoma decreased in White Americans, Israel, Uganda, Costa Rica, Colombia, Canada, and Denmark, from 1998 to 2012. INTERPRETATION: Kaposi sarcoma is a relatively rare cancer worldwide but is endemic in some countries in southern and eastern Africa. Addressing disparities in health-care resource allocation and improving HIV/AIDS care across different HDI regions might contribute to the prevention of Kaposi sarcoma. FUNDING: The Natural Science Foundation of China Excellent Young Scientists Fund and the Natural Science Foundation of China International/Regional Research Collaboration Project. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.
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Síndrome da Imunodeficiência Adquirida , Sarcoma de Kaposi , Feminino , Masculino , Humanos , Sarcoma de Kaposi/epidemiologia , Projetos de Pesquisa , Canadá , UgandaRESUMO
BACKGROUND: In 2003, China implemented free antiretroviral therapy (ART) for people living with HIV (PLHIV), establishing an eligibility threshold of CD4 < 200 cells/µl. Subsequently, the entry criteria were revised in 2012 (eligibility threshold: CD4 ≤ 350 cells/µl), 2014 (CD4 ≤ 500 cells/µl), and 2016 (treat-all). However, the impact of treat-all policy on HIV care and treatment indicators in China is unknown. We aimed to elucidate the immediate and long-term impact of the implementation of treat-all policy in China. METHODS: Anonymized programmatic data on ART initiation and collection in PLHIV who newly started ART were retrieved between 1 January 2015 and 31 December 2019, from two provincial and municipal Centers for Disease Control and Prevention and ten major infectious disease hospitals specialized in HIV care in China. We used Poisson and quasi-Poisson segmented regression models to estimate the immediate and long-term impact of treat-all on three key indicators: monthly proportion of 30-day ART initiation, mean CD4 counts (cells/µl) at ART initiation, and mean estimated time from infection to diagnosis (year). We built separate models according to gender, age, route of transmission and region. RESULTS: Monthly data on ART initiation and collection were available for 75,516 individuals [gender: 83.8% males; age: median 39 years, interquartile range (IQR): 28-53; region: 18.5% Northern China, 10.9% Northeastern China, 17.5% Southern China, 49.2% Southwestern China]. In the first month of treat-all, compared with the contemporaneous counterfactual, there was a significant increase in proportion of 30-day ART initiation [+ 12.6%, incidence rate ratio (IRR) = 1.126, 95% CI: 1.033-1.229; P = 0.007] and mean estimated time from infection to diagnosis (+ 7.0%, IRR = 1.070, 95% CI: 1.021-1.120; P = 0.004), while there was no significant change in mean CD4 at ART initiation (IRR = 0.990, 95% CI: 0.956-1.026; P = 0.585). By December 2019, the three outcomes were not significantly different from expected levels. In the stratified analysis, compared with the contemporaneous counterfactual, mean CD4 at ART initiation showed significant increases in Northern China (+ 3.3%, IRR = 1.033, 95% CI: 1.001-1.065; P = 0.041) and Northeastern China (+ 8.0%, IRR = 1.080, 95% CI: 1.003-1.164; P = 0.042) in the first month of treat-all; mean estimated time from infection to diagnosis showed significant increases in male (+ 5.6%, IRR = 1.056, 95% CI: 1.010-1.104; P = 0.016), female (+ 14.8%, IRR = 1.148, 95% CI: 1.062-1.240; P < 0.001), aged 26-35 (+ 5.3%, IRR = 1.053, 95% CI: 1.001-1.109; P = 0.048) and > 50 (+ 7.8%, IRR = 1.078, 95% CI: 1.000-1.161; P = 0.046), heterosexual transmission (+ 12.4%, IRR = 1.124, 95% CI: 1.042-1.213; P = 0.002) and Southwestern China (+ 12.9%, IRR = 1.129, 95% CI: 1.055-1.208; P < 0.001) in the first month of treat-all. CONCLUSIONS: The implementation of treat-all policy in China was associated with a positive effect on HIV care and treatment outcomes. To advance the work of rapid ART, efforts should be made to streamline the testing and ART initiation process, provide comprehensive support services, and address the issue of uneven distribution of medical resources.
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Fármacos Anti-HIV , Infecções por HIV , Adulto , Feminino , Humanos , Masculino , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , China/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/diagnóstico , Análise de Séries Temporais Interrompida , Resultado do Tratamento , Pessoa de Meia-IdadeRESUMO
Eleven genera and thirteen species of the tortricid tribe Enarmoniini documented from Taiwan are listed. One species, Semnostola tristrigma sp. nov., is described as new to science. Two species, Ancylis unculana (Haworth, [1811]) and Neoanathamna pallens Kawabe, 1980 along with their genera, are newly recorded for Taiwan. Images of the adults and genitalia are provided for the new species.
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Lepidópteros , Mariposas , Animais , Taiwan , Genitália , Distribuição AnimalRESUMO
Passive solar desalination with interfacial heating is a promising technique to utilize solar energy to convert seawater into fresh water through evaporation and condensation. However, the current freshwater flux of solar desalination is much below industrial requirements (> 20 L m-2 h-1 ). Herein, it is demonstrated that a 3D plasmonic evaporator with an efficient heat-mass evaporation interface (HM-EI) achieves a freshwater flux of 29.1 L m-2 h-1 for 3.5 wt.% NaCl, which surpasses the previous solar evaporators and approaches the level of reverse osmosis (the highest installed capacity in industrial seawater desalination technology). The realization of high freshwater flux solar desalination comes from the efficient HM-EI comprising a grid-like plasmonic macrostructure for enhanced energy utilization in heat properties and a large-pore microstructure for accelerated ion transport in mass properties. This work provides a new direction for designing next-generation solar evaporators with high freshwater flux for industrial requirements.
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Formamidinium lead triiodide (FAPbI3) is considered as the prospective light-absorbing layer on account of the close-to-ideal bandgap of theα-phase, wide optical absorption spectrum and good thermal stability. Therefore, how to realizeδtoα-phase transition to obtain phase-pureα-FAPbI3without additives is important for FAPbI3perovskite films. Herein, a homologous post-treatment strategy (HPTS) without additives is proposed to prepare FAPbI3films with pureα-phase. The strategy is processed along with dissolution and reconstruction process during the annealing. The FAPbI3film has tensile strain with the substrate, and the lattice keeps tensile, and the film maintains in anα/δhybrid phase. The HPTS process releases the tensile strain between the lattice and the substrate. The process of strain release realizes the phase transition fromδtoα-phase during this process. This strategy can accelerate the transformation from hexagonalδ-FAPbI3to cubicα-FAPbI3at 120 °C. As a result, the acquiredα-FAPbI3films exhibit better film quality in optical and electrical properties, accordingly achieving device efficiency of 19.34% and enhanced stability. This work explores an effective approach to obtain additive-free and phase-pureα-FAPbI3films through a HPTS to fabricate uniform high-performanceα-FAPbI3perovskite solar cells.
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Óxidos , Estudos Prospectivos , Transição de FaseRESUMO
Interfacial atomic configuration plays a vital role in the structural stability and functionality of nanocomposites composed of metal nanoparticles (NPs) and two-dimensional semiconductors. In situ transmission electron microscope (TEM) provides a real-time technique to observe the interface structure at atomic resolution. Herein, we loaded bimetallic NiPt truncated octahedral NPs (TONPs) on MoS2 nanosheets and constructed a NiPt TONPs/MoS2 heterostructure. The interfacial structure evolution of NiPt TONPs on MoS2 was in situ investigated using aberration-corrected TEM. It was observed that some NiPt TONPs exhibited lattice matching with MoS2 and displayed remarkable stability under electron beam irradiation. Intriguingly, the rotation of an individual NiPt TONP can be triggered by the electron beam to match the MoS2 lattice underneath. Furthermore, the coalescence kinetics of NiPt TONPs can be quantitatively described by the relationship between neck radius (r) and time (t), expressed as rn = Kt. Our work offers a detailed analysis of the lattice alignment relationship of NiPt TONPs on MoS2, which may enlighten the design and preparation of stable bimetallic metal NPs/MoS2 heterostructures.
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Voluntary medical male circumcision (VMMC) may be incorporated into HIV prevention services for men who have sex with men (MSM). We conducted a mixed-methods study to elucidate barriers and facilitators to, and experience of, VMMC among MSM. Participants were MSM aged 18 years and older who were enrolled in an ongoing multicenter randomized controlled trial (RCT) to evaluate VMMC to prevent HIV among MSM in China. RCT participants completed a questionnaire before and after VMMC to assess perceptions of and complications after the procedure. A subset of RCT participants were selected for in-depth interviews. Interviewees answered open-ended questions about barriers and facilitators to and experience of undergoing VMMC. Six-step thematic analysis incorporating inductive and deductive approaches was used to interpret interview responses. A total of 457 MSM completed the pre-VMMC survey, 115 circumcised MSM completed post-VMMC surveys, and 30 MSM completed an interview. Main barriers to VMMC uptake were concerns about pain, length of wound healing, cost, lack of knowledge about or misconceptions of VMMC, and stigma related to surgery. Facilitators to VMMC could be categorized as internal factors (foreskin) and external factors (motivation and follow-up care). Interestingly, the VMMC experiences of others could be transformed from a barrier into a facilitator to VMMC in some circumstances. After VMMC participants transitioned from a negative state of pain, remorse, difficulty sleeping, and discomfort to a positive state of symptom alleviation and personal hygiene improvement. Optimizing facilitators and addressing barriers may encourage VMMC among MSM. Joint efforts should be made by relevant stakeholders to improve the awareness and uptake of VMMC among MSM.
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Circuncisão Masculina , Infecções por HIV , Minorias Sexuais e de Gênero , Masculino , Humanos , Infecções por HIV/prevenção & controle , China , DorRESUMO
BACKGROUND: Predicting left ventricular recovery (LVR) after acute ST-segment elevation myocardial infarction (STEMI) is of prognostic importance. This study aims to explore the prognostic implications of segmental noninvasive myocardial work (MW) and microvascular perfusion (MVP) after STEMI. METHODS: In this retrospective study, 112 patients with STEMI who underwent primary percutaneous coronary intervention and transthoracic echocardiography after percutaneous coronary intervention were enrolled. Microvascular perfusion was analyzed by myocardial contrast echocardiography, and segmental MW was analyzed by noninvasive pressure-strain loops. A total of 671 segments with abnormal function at baseline were analyzed. The degrees of MVP were observed following intermittent high-mechanical index impulses: replenishment within 4 seconds (normal MVP), replenishment >4 seconds and within 10 seconds (delayed MVP), and persistent defect (microvascular obstruction). The correlation between MW and MVP was analyzed. The correlation of the MW and MVP with LVR (normalization of wall thickening, >25%) was assessed. The prognostic value of segmental MW and MVP for cardiac events (cardiac death, admission for congestive heart failure, or recurrent myocardial infarction) was evaluated. RESULTS: Normal MVP was seen in 70 segments, delayed MVP in 236, and microvascular obstruction in 365. The segmental MW indices were independently correlated with MVP; 244 (36.4%) segments had segmental LVR at 3-month follow-up. Segmental MW efficiency and MVP were independently associated with segmental LVR (P < .05). The χ2 of combination of segmental MW efficiency and MVP was higher than either index alone for identifying segmental LVR (P < .001). At a median follow-up of 42.0 months, cardiac events occurred in 13 patients; all regional MW parameters, high sensitivity troponin I, regional longitudinal strain, and so on were associated with cardiac events. CONCLUSIONS: Segmental MW indices are associated with MVP within the infarct zone following reperfused STEMI. Both are independently associated with segmental LVR, and regional MW is associated with cardiac events, providing prognostic value in STEMI patients.
Assuntos
Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Estudos Retrospectivos , Ecocardiografia , Prognóstico , Perfusão , Função Ventricular EsquerdaRESUMO
BACKGROUND: Systematic reviews and meta-analyses based on observational studies have shown voluntary medical male circumcision (VMMC) may reduce HIV risk among men who have sex with men (MSM). There is a lack of randomized controlled trial (RCT) data assessing the efficacy of VMMC. OBJECTIVE: The primary objective of this study was to assess the efficacy of VMMC for preventing HIV acquisition among MSM who primarily engage in insertive anal sex. METHODS: A multicenter RCT will be conducted among MSM in 8 cities in China. Eligible participants are men aged 18-49 years who self-report ≥2 male sex partners in the past 6 months, predominantly practice insertive anal sex, and are willing to undergo circumcision. Interested men who satisfy inclusion criteria will be tested for HIV 1 month before enrollment and at enrollment, and only those who are HIV negative will be enrolled. At baseline, all enrolled participants will be asked to report sociodemographic characteristics and sexual behaviors; provide a blood sample for HIV, syphilis, and herpes simplex virus type 2 testing; and provide a penile swab for human papillomavirus testing. Participants will be randomly assigned to the intervention or control group. Those in the intervention group will receive VMMC and undergo a web-based weekly follow-up assessment of postsurgery healing for 6 consecutive weeks. All participants will be tested for HIV at 3-, 6-, 9-, and 12-month follow-ups. All participants will also be asked to report sexual behaviors and undergo repeat herpes simplex virus type 2 and human papillomavirus testing at 6- and 12-month follow-ups. The primary end point is HIV seroconversion. Secondary end points are the safety and satisfaction with VMMC and the changes in sexual behaviors after VMMC. The grouped censored data will be analyzed by intention-to-treat approach. RESULTS: Recruitment for the RCT began in August 2020 and continued through July 2022. Data collection is expected to be completed by July 2023, and full data analysis is going to be completed by September 2023. CONCLUSIONS: This study will be the first RCT to assess the efficacy of VMMC in preventing HIV infection among MSM. Results from this trial will provide preliminary evidence for the potential efficacy of VMMC to reduce incident HIV infection among MSM. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2000039436; https://www.chictr.org.cn/showproj.html?proj=63369. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/47160.