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1.
Nat Mater ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769206

RESUMO

Structurally ordered L10-PtM (M = Fe, Co, Ni and so on) intermetallic nanocrystals, benefiting from the chemically ordered structure and higher stability, are one of the best electrocatalysts used for fuel cells. However, their practical development is greatly plagued by the challenge that the high-temperature (>600 °C) annealing treatment necessary for realizing the ordered structure usually leads to severe particle sintering, morphology change and low ordering degree, which makes it very difficult for the gram-scale preparation of desirable PtM intermetallic nanocrystals with high Pt content for practical fuel cell applications. Here we report a new concept involving the low-melting-point-metal (M' = Sn, Ga, In)-induced bond strength weakening strategy to reduce Ea and promote the ordering process of PtM (M = Ni, Co, Fe, Cu and Zn) alloy catalysts for a higher ordering degree. We demonstrate that the introduction of M' can reduce the ordering temperature to extremely low temperatures (≤450 °C) and thus enable the preparation of high-Pt-content (≥40 wt%) L10-Pt-M-M' intermetallic nanocrystals as well as ten-gram-scale production. X-ray spectroscopy studies, in situ electron microscopy and theoretical calculations reveal the fundamental mechanism of the Sn-facilitated ordering process at low temperatures, which involves weakened bond strength and consequently reduced Ea via Sn doping, the formation and fast diffusion of low-coordinated surface free atoms, and subsequent L10 nucleation. The developed L10-Ga-PtNi/C catalysts display outstanding performance in H2-air fuel cells under both light- and heavy-duty vehicle conditions. Under the latter condition, the 40% L10-Pt50Ni35Ga15/C catalyst delivers a high current density of 1.67 A cm-2 at 0.7 V and retains 80% of the current density after extended 90,000 cycles, which exceeds the United States Department of Energy performance metrics and represents among the best cathodic electrocatalysts for practical proton-exchange membrane fuel cells.

2.
Nature ; 574(7776): 81-85, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31554968

RESUMO

The efficient interconversion of chemicals and electricity through electrocatalytic processes is central to many renewable-energy initiatives. The sluggish kinetics of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER)1-4 has long posed one of the biggest challenges in this field, and electrocatalysts based on expensive platinum-group metals are often required to improve the activity and durability of these reactions. The use of alloying5-7, surface strain8-11 and optimized coordination environments12 has resulted in platinum-based nanocrystals that enable very high ORR activities in acidic media; however, improving the activity of this reaction in alkaline environments remains challenging because of the difficulty in achieving optimized oxygen binding strength on platinum-group metals in the presence of hydroxide. Here we show that PdMo bimetallene-a palladium-molybdenum alloy in the form of a highly curved and sub-nanometre-thick metal nanosheet-is an efficient and stable electrocatalyst for the ORR and the OER in alkaline electrolytes, and shows promising performance as a cathode in Zn-air and Li-air batteries. The thin-sheet structure of PdMo bimetallene enables a large electrochemically active surface area (138.7 square metres per gram of palladium) as well as high atomic utilization, resulting in a mass activity towards the ORR of 16.37 amperes per milligram of palladium at 0.9 volts versus the reversible hydrogen electrode in alkaline electrolytes. This mass activity is 78 times and 327 times higher than those of commercial Pt/C and Pd/C catalysts, respectively, and shows little decay after 30,000 potential cycles. Density functional theory calculations reveal that the alloying effect, the strain effect due to the curved geometry, and the quantum size effect due to the thinness of the sheets tune the electronic structure of the system for optimized oxygen binding. Given the properties and the structure-activity relationships of PdMo metallene, we suggest that other metallene materials could show great promise in energy electrocatalysis.

3.
J Am Chem Soc ; 146(28): 19327-19336, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38976776

RESUMO

An in situ formed IrOx (x ≤ 2) layer driven by anodic bias serves as the essential active site of Ir-based materials for oxygen evolution reaction (OER) electrocatalysis. Once being confined to atomic thickness, such an IrOx layer possesses both a favorable ligand effect and maximized active Ir sites with a lower O-coordination number. However, limited by a poor understanding of surface reconstruction dynamics, obtaining atomic layers of IrOx remains experimentally challenging. Herein, we report an idea of material design using intermetallic IrVMn nanoparticles to induce in situ formation of an ultrathin IrOx layer (O-IrVMn/IrOx) to enable the ligand effect for achieving superior OER electrocatalysis. Theoretical calculations predict that a strong electronic interaction originating from an orderly atomic arrangement can effectively hamper the excessive leaching of transition metals, minimizing vacancies for oxygen coordination. Linear X-ray absorption near edge spectra analysis, extended X-ray absorption fine structure fitting outcomes, and X-ray photoelectron spectroscopy collectively confirm that Ir is present in lower oxidation states in O-IrVMn/IrOx due to the presence of unsaturated O-coordination. Consequently, the O-IrVMn/IrOx delivers excellent acidic OER performances with an overpotential of only 279 mV at 10 mA cm-2 and a high mass activity of 2.3 A mg-1 at 1.53 V (vs RHE), exceeding most Ir-based catalysts reported. Moreover, O-IrVMn/IrOx also showed excellent catalytic stability with only 0.05 at. % Ir dissolution under electrochemical oxidation, much lower than that of disordered D-IrVMn/IrOx (0.20 at. %). Density functional theory calculations unravel that the intensified ligand effect optimizes the adsorption energies of multiple intermediates involved in the OER and stabilizes the as-formed catalytic IrOx layer.

4.
J Med Virol ; 96(1): e29338, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38163280

RESUMO

Monkeypox (mpox), a viral zoonotic disease, is spreading worldwide. However, evidence that informs prevention and control strategies in the Asia Pacific Region is very limited. Our study aims to investigate the experiences of mpox patients from infection to treatment to provide scientific basis for the prevention and control. A multicenter qualitative design was used. A total of 15 mpox patients were recruited between July 6 and July 25, 2023, from six cities in China. Semistructured interviews were conducted by telephone and analyzed using the thematic analysis. The interview was divided into two sections: patients' experiences (prediagnosis experience, treatment-seeking experience, and quarantine experience) and advice. Prediagnosis experience was summarized into three themes: symptoms, possible routes of infection, and knowledge of mpox. Treatment-seeking experience was summarized into three themes: time of visit to hospital, diagnostic difficulties, and attitude toward diagnosis. Quarantine experience was summarized into three themes: body and mind reactions, reluctance to self-disclose infection status, and factors facilitating recovery. Themes identified from patients' advice were as follows: (1) Increase in testing channels and methods, (2) Development and introduction of vaccines, (3) Adjustment of quarantine program, (4) Improvement of treatment measures, and (5) Improvement of publicity and education. To effectively curb the mpox epidemic, structured measures are urgently needed to address the mpox-related stigma and discrimination. Targeted health education should be provided to MSM, focusing on the prevention, detection, and treatment services. Hospitals should enhance the training of clinicians in key departments including infectious disease and dermatology, to improve diagnostic capability and sensitivity. Furthermore, given the absence of specific antiviral medications, supervised home quarantine may be a good option.


Assuntos
Mpox , Humanos , China/epidemiologia , Ásia , Antivirais , Cidades
5.
AIDS Care ; : 1-9, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526977

RESUMO

Mental health problems leads to serious disease burden among people living with HIV/AIDS (PLHIV). The study aimed at measuring the mental disorders-caused burden of disease based on PLHIV in mainland China. The data used was from the national HIV/AIDS case reporting system, life expectancy (LE) and LE-eliminated suicide were evaluated by the life-table method. The total YLLs and YLLs caused by suicide in each age group were calculated. The disability weights were estimated by the scale of depression symptoms (CES-D) from the multi-center cross-sectional survey, then calculated the corresponding YLDs as a burden of mental illness among PLHIV. Results showed that the LE had been prolonged by implementing antiviral therapy for PLHIV. The proportion of YLLs caused by suicide was the highest (5·46%) in the 15-24 age group. The YLDs in the 25-34 age group were the highest. The YLLs caused by suicide in males were higher than those in the same age group of females. The YLDs and YLLs were higher in heterosexual-infected PLHIV than in homosexual-infected PLHIV, except for YLLs in the 25-34 age group. In summary, this study first provided localized data on the disease burden caused by mental health problems among PLHIV.

6.
Sensors (Basel) ; 24(7)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38610548

RESUMO

For direction-of-arrival (DOA) estimation problems in a sparse domain, sparse Bayesian learning (SBL) is highly favored by researchers owing to its excellent estimation performance. However, traditional SBL-based methods always assign Gaussian priors to parameters to be solved, leading to moderate sparse signal recovery (SSR) effects. The reason is Gaussian priors play a similar role to l2 regularization in sparsity constraint. Therefore, numerous methods are developed by adopting hierarchical priors that are used to perform better than Gaussian priors. However, these methods are in straitened circumstances when multiple measurement vector (MMV) data are adopted. On this basis, a block-sparse SBL method (named BSBL) is developed to handle DOA estimation problems in MMV models. The novelty of BSBL is the combination of hierarchical priors and block-sparse model originating from MMV data. Therefore, on the one hand, BSBL transfers the MMV model to a block-sparse model by vectorization so that Bayesian learning is directly performed, regardless of the prior independent assumption of different measurement vectors and the inconvenience caused by the solution of matrix form. On the other hand, BSBL inherited the advantage of hierarchical priors for better SSR ability. Despite the benefit, BSBL still has the disadvantage of relatively large computation complexity caused by high dimensional matrix operations. In view of this, two operations are implemented for low complexity. One is reducing the matrix dimension of BSBL by approximation, generating a method named BSBL-APPR, and the other is embedding the generalized approximate message passing (GAMB) technique into BSBL so as to decompose matrix operations into vector or scale operations, named BSBL-GAMP. Moreover, BSBL is able to suppress temporal correlation and handle wideband sources easily. Extensive simulation results are presented to prove the superiority of BSBL over other state-of-the-art algorithms.

7.
Angew Chem Int Ed Engl ; 63(11): e202319108, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38196079

RESUMO

Engineering isolated metal sites resembling the primary coordination sphere of metallocofactors enables atomically dispersed materials as promising nanozymes. However, most existing nanozymes primarily focus on replicating specific metallocofactors while neglecting other supporting cofactors within active pockets, leading to reduced electron transfer (ET) efficiency and thus inferior catalytic performances. Herein, we report a metal-organic framework UiO-67 nanozyme with atomically dispersed iron sites, which involves multiple tailored enzyme-like nanocofactors that synergistically drive the ET process for enhanced peroxidase-like catalysis. Among them, the linker-coupled atomic iron site plays a critical role in substrate activation, while bare linkers and zirconia nodes facilitate the ET efficiency of intermediates. The synergy of three nanocofactors results in a 4.29-fold enhancement compared with the single effort of isolated metal site-based nanocofactor, holding promise in immunoassay for sensitive detection of chlorpyrifos. This finding opens a new way for designing high-performance nanozymes by harmonizing various nanocofactors at the atomic and molecular scale.


Assuntos
Oxirredutases , Peroxidase , Peroxidases , Ferro/química , Catálise
8.
J Am Chem Soc ; 145(39): 21432-21441, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37728051

RESUMO

Although dispersing Pt atomic clusters (ACs) on a conducting support is a promising way to minimize the Pt amount required in hydrogen evolution reaction (HER), the catalytic mass activity and durability of Pt ACs are often unsatisfactory for alkaline HER due to their unfavorable water dissociation and challenges in stabilizing them against agglomeration and detachment. Herein, we report a class of single-atom Cr-N4 sites with high oxophilicity interfaced with Pt ACs on mesoporous carbon for achieving a highly active and stable alkaline HER in an anion-exchange-membrane water electrolyzer (AEMWE). The as-made catalyst achieves the highest reported Pt mass activity (37.6 times higher than commercial Pt/C) and outstanding operational stability. Experimental and theoretical studies elucidate that the formation of a unique Pt-Cr quasi-covalent bonding interaction at the interface of Cr-N4 sites and Pt ACs effectively suppresses the migration and thermal vibration of Pt atoms to stabilize Pt ACs and contributes to the greatly enhanced catalytic stability. Moreover, oxophilic Cr-N4 sites adjacent to Pt ACs with favorable adsorption of hydroxyl species facilitate nearly barrierless water dissociation and thus enhance the HER activity. An AEMWE using this catalyst (with only 50 µgPt cm-2) can operate stably at an industrial-level current density of 500 mA cm-2 at 1.8 V for >100 h with a small degradation rate of 90 µV h-1.

9.
J Hepatol ; 78(1): 16-27, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35988691

RESUMO

BACKGROUND & AIMS: The pandemic has resulted in an increase of deaths not directly related to COVID-19 infection. We aimed to use a national death dataset to determine the impact of the pandemic on people with liver disease in the USA, focusing on alcohol-associated liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD). METHODS: Using data from the National Vital Statistic System from the Center for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research (CDC WONDER) platform and ICD-10 codes, we identified deaths associated with liver disease. We evaluated observed vs. predicted mortality for 2020-2021 based on trends from 2010-2019 with joinpoint and prediction modelling analysis. RESULTS: Among 626,090 chronic liver disease-related deaths between 2010 and 2021, Age-standardised mortality rates (ASMRs) for ALD dramatically increased between 2010-2019 and 2020-2021 (annual percentage change [APC] 3.5% to 17.6%, p <0.01), leading to a higher observed ASMR (per 100,000 persons) than predicted for 2020 (15.67 vs. 13.04) and 2021 (17.42 vs. 13.41). ASMR for NAFLD also increased during the pandemic (APC: 14.5%), whereas the rates for hepatitis B and C decreased. Notably, the ASMR rise for ALD was most pronounced in non-Hispanic Whites, Blacks, and Alaska Indians/Native Americans (APC: 11.7%, 10.8%, 18.0%, all p <0.05), with similar but less critical findings for NAFLD, whereas rates were steady for non-Hispanic Asians throughout 2010-2021 (APC: 4.9%). The ASMR rise for ALD was particularly severe for the 25-44 age group (APC: 34.6%, vs. 13.7% and 12.6% for 45-64 and ≥65, all p <0.01), which were also all higher than pre-COVID-19 rates (all p <0.01). CONCLUSIONS: ASMRs for ALD and NAFLD increased at an alarming rate during the COVID-19 pandemic with the largest disparities among the young, non-Hispanic White, and Alaska Indian/Native American populations. IMPACT AND IMPLICATIONS: The pandemic has led to an increase of deaths directly and indirectly related to SARS-CoV-2 infection. As shown in this study, age-standardised mortality rates for alcohol-associated liver disease and non-alcoholic fatty liver disease substantially increased during the COVID-19 pandemic in the USA and far exceeded expected levels predicted from past trends, especially among the young, non-Hispanic White, and Alaska Indian/Native American populations. However, much of this increase was not directly related to COVID-19. Therefore, for the ongoing pandemic as well as its recovery phase, adherence to regular monitoring and care for people with chronic liver disease should be prioritised and awareness should be raised among patients, care providers, healthcare systems, and public health policy makers.


Assuntos
COVID-19 , Hepatopatias Alcoólicas , Hepatopatia Gordurosa não Alcoólica , Estados Unidos/epidemiologia , Humanos , Pandemias , Hepatopatia Gordurosa não Alcoólica/epidemiologia , SARS-CoV-2 , Hepatopatias Alcoólicas/epidemiologia
10.
Am J Gastroenterol ; 118(4): 752-757, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36728136

RESUMO

INTRODUCTION: Our aim was to evaluate the impact of race/ethnicity on cirrhosis-related premature death during the COVID-19 pandemic. METHODS: We obtained cirrhosis-related death data (n = 872,965, January 1, 2012-December 31, 2021) from the US National Vital Statistic System to calculate age-standardized mortality rates and years of potential life lost (YPLL) for premature death aged 25-64 years. RESULTS: Significant racial/ethnic disparity in cirrhosis-related age-standardized mortality rates was noted prepandemic but widened during the pandemic, with the highest excess YPLL for the non-Hispanic American Indian/American Native (2020: 41.0%; 2021: 68.8%) followed by other minority groups (28.7%-45.1%), and the non-Hispanic White the lowest (2020: 20.7%; 2021: 31.6%). COVID-19 constituted >30% of the excess YPLLs for Hispanic and non-Hispanic American Indian/American Native in 2020, compared with 11.1% for non-Hispanic White. DISCUSSION: Ethnic minorities with cirrhosis experienced a disproportionate excess death and YPLLs in 2020-2021.


Assuntos
COVID-19 , Cirrose Hepática , Humanos , Etnicidade , Hispânico ou Latino , Cirrose Hepática/mortalidade , Pandemias , Estados Unidos/epidemiologia , Indígena Americano ou Nativo do Alasca
11.
J Intern Med ; 294(2): 178-190, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37095702

RESUMO

BACKGROUND: US progress toward ending the HIV epidemic was disrupted during the COVID-19 pandemic. OBJECTIVES: To determine the impact of the pandemic on HIV-related mortality and potential disparities. METHODS: Using data from the Centers for Disease Control and Prevention and the United States (US) Census Bureau, HIV-related mortality data of decedents aged ≥25 years between 2012 and 2021 were analyzed. Excess HIV-related mortality rates were estimated by determining the difference between observed and projected mortality rates during the pandemic. The trends of mortality were quantified with joinpoint regression analysis. RESULTS: Of the 79,725 deaths documented in adults aged 25 years and older between 2012 and 2021, a significant downward trend was noted in HIV-related mortality rates before the pandemic, followed by a surge during the pandemic. The observed mortality rates were 18.8% (95% confidence interval [CI]: 13.1%-25.5%) and 25.4% (95%CI: 19.9%-30.4%) higher than the projected values in 2020 and 2021, respectively. Both of these percentages were higher than that in the general population in 2020 (16.4%, 95%CI: 14.9%-17.9%) and 2021 (19.8%, 95%CI: 18.0%-21.6%), respectively. Increased HIV-related mortality was observed across all age subgroups, but those aged 25-44 years demonstrated the greatest relative increase and the lowest COVID-19-related deaths when compared to middle- and old-aged decedents. Disparities were observed across racial/ethnic subgroups and geographic regions. CONCLUSIONS: The pandemic led to a reversal in the attainments made to reduce the prevalence of HIV. Individuals living with HIV were disproportionately affected during the pandemic. Thoughtful policies are needed to address the disparity in excess HIV-related mortality.


Assuntos
COVID-19 , Infecções por HIV , Adulto , Humanos , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Idoso , Pandemias , Grupos Raciais , Previsões , Infecções por HIV/epidemiologia , Mortalidade
12.
J Med Virol ; 95(1): e28187, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36176195

RESUMO

The COVID-19 pandemic has had a detrimental impact on the healthcare system. Our study armed to assess the extent and the disparity in excess acute myocardial infarction (AMI)-associated mortality during the pandemic, through the recent Omicron outbreak. Using data from the CDC's National Vital Statistics System, we identified 1 522 669 AMI-associated deaths occurring between 4/1/2012 and 3/31/2022. Accounting for seasonality, we compared age-standardized mortality rate (ASMR) for AMI-associated deaths between prepandemic and pandemic periods, including observed versus predicted ASMR, and examined temporal trends by demographic groups and region. Before the pandemic, AMI-associated mortality rates decreased across all subgroups. These trends reversed during the pandemic, with significant rises seen for the youngest-aged females and males even through the most recent period of the Omicron surge (10/2021-3/2022). The SAPC in the youngest and middle-age group in AMI-associated mortality increased by 5.3% (95% confidence interval [CI]: 1.6%-9.1%) and 3.4% (95% CI: 0.1%-6.8%), respectively. The excess death, defined as the difference between the observed and the predicted mortality rates, was most pronounced for the youngest (25-44 years) aged decedents, ranging from 23% to 34% for the youngest compared to 13%-18% for the oldest age groups. The trend of mortality suggests that age and sex disparities have persisted even through the recent Omicron surge, with excess AMI-associated mortality being most pronounced in younger-aged adults.


Assuntos
COVID-19 , Infarto do Miocárdio , Adulto , Masculino , Pessoa de Meia-Idade , Feminino , Humanos , Idoso , Pandemias , Estudos Retrospectivos , Infarto do Miocárdio/epidemiologia
13.
J Med Virol ; 95(10): e29198, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37881113

RESUMO

Human mpox is occurring worldwide, however, evidence from the Asian Pacific Region is limited. In this multicenter cross-sectional study, information of confirmed mpox cases diagnosed between June 1 and July 31, 2023 in China. Information included demographic and epidemiological characteristics, and clinical manifestations, laboratory results, and mental health status of mpox cases. A total of 115 confirmed mpox cases were enrolled. All cases were men. A total of 102 (90.3%) identified as homosexual. The median age was 31.0 years (interquartile range 27.0-36.5). A total of 65 (56.5%) were HIV-positive, of whom 92.3% were receiving antiretroviral therapy (ART). A total of 19/39 (40.4%) had a CD4 cell count <500 cells/µL. Systemic features such as fever (73.0%), lymphadenopathies (49.6%), and myalgia (28.7%) were commonly observed. Skin lesions were present in all participants: 49.6% in the genital area and 27.0% in the perianal area. Vesicular rash (78.3%) and papular rash (44.3%) were the most common lesion morphologies. People living with HIV were more likely to have anxiety than those living without HIV. The majority of mpox cases had primary genital lesions and sexual activities before diagnosis, which supports the likelihood of sexual contact transmission. Guidelines on hospitalization and isolation protocols for mpox patients necessitate further confirmation.


Assuntos
Exantema , Infecções por HIV , Mpox , Adulto , Humanos , Masculino , China/epidemiologia , Estudos Transversais , Nível de Saúde , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia
14.
BMC Infect Dis ; 23(1): 527, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37563554

RESUMO

INTRODUCTION: The COVID-19 epidemic control and prevention strategies affected people's sexual activities and behaviors. Little was known about long-term effects of COVID-19 prevention and control strategies on sexual behaviors among men who have sex with men (MSM). This study aimed to examine changes in risky sexual behaviors of MSM before and after the local epidemic. METHODS: An online survey was conducted nationwide from June 1 to June 10, 2022. MSM aged 16 years and above, residing in China were recruited through convenience sampling. A generalized estimating equation model with modified Poisson regression was used to analyze changes in multiple sexual partners, unprotected sex, mobility for sexual activity, and recreational substance use before and after the local epidemic. RESULTS: Compared to the pre-pandemic (36.5%), the prevalence of multiple sexual partners (11.5%) significantly decreased during the local epidemic and then increased after the local epidemic (25.2%) but remained lower than pre-pandemic, as did the prevalence of unprotected sex (31.1%, 19.4%, and 26.1%), mobility for sexual activity (7.5%, 2.8%, and 4.1%) and recreational substance use (47.7%, 27.2%, and 39.5%). Compared to the pre-pandemic, higher declines in the prevalence of risky sexual behaviors during the local epidemic existed among MSM living without a regular partner (44% decrease in unprotected sex and 46% in recreational substance use), with a bachelor's degree and above (70% decrease in multiple sex partners, 39% in unprotected sex, 67% in mobility for sexual activity and 44% in recreational substance use), higher incomes (70% decrease in multiple sex partners), self-identified gay or bisexual/unsure (38-71%), and HIV infection (49-83% decrease respectively in these four indicators). After the local epidemic, the declines in the above indicators compared to the pre-pandemic were correspondingly. And higher declines existed among MSM living without a regular partner (8% decrease in unprotected sex and 13% in recreational substance use), with a bachelor's degree and above (33% decrease in multiple sex partners), higher incomes (55% decrease in mobility for sexual activity), self-identified gay (51% decrease in mobility for sexual activity), and HIV infection (32%, 68%, 24% decrease respectively in unprotected sex, mobility for sexual activity and recreational substance use). CONCLUSIONS: Risky sexual behaviors reduced considerably during the local epidemic, then seemed rebounded after the outbreak but wouldn't return to pre-pandemic levels. More attention should be paid to vulnerable people with lower socio-economic status, HIV-positive, and sexual minorities for sustained HIV and COVID-19 prevention.


Assuntos
COVID-19 , Infecções por HIV , Minorias Sexuais e de Gênero , Transtornos Relacionados ao Uso de Substâncias , Masculino , Humanos , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Estudos Transversais , Pandemias , COVID-19/epidemiologia , Comportamento Sexual , Parceiros Sexuais , China/epidemiologia , Assunção de Riscos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
15.
J Eur Acad Dermatol Venereol ; 37(6): 1221-1227, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36808772

RESUMO

BACKGROUND: Little is known about mortality trends among patients with psoriasis (PsO) and psoriatic arthritis (PsA) in the United States. OBJECTIVES: To ascertain mortality trends of PsO and PsA between 2010 and 2021, focusing on the effects of the COVID-19 pandemic. METHODS: We collected data from the National Vital Statistic System and calculated age-standardized mortality rates (ASMR) and cause-specific mortality for PsO/PsA. We evaluated observed versus predicted mortality for 2020-2021 based on trends from 2010 to 2019 with joinpoint and prediction modelling analysis. RESULTS: Among 5810 and 2150 PsO- and PsA-related deaths between 2010 and 2021, ASMR for PsO dramatically increased between 2010-2019 and 2020-2021 (annual percentage change [APC] 2.07% vs. 15.26%; p < 0.01), leading to a higher observed ASMR (per 100,000 persons) than predicted for 2020 (0.27 vs. 0.22) and 2021 (0.31 vs. 0.23). The excess mortality of PsO was 22.7% and 34.8% higher than that in the general population in 2020 (16.4%, 95% CI: 14.9%-17.9%) and 2021 (19.8%, 95% CI: 18.0%-21.6%) respectively. Notably, the ASMR rise for PsO was most pronounced in the female (APC: 26.86% vs. 12.19% in males) and the middle-aged group (APC: 17.67% vs. 12.47% in the old-age group). ASMR, APC and excess mortality for PsA were similar to PsO. SARS-CoV-2 infection contributed to more than 60% of the excess mortality for PsO and PsA. CONCLUSIONS: Individuals living with PsO and PsA were disproportionately affected during the COVID-19 pandemic. Both ASMRs increased at an alarming rate, with the most pronounced disparities among the female and middle-aged groups.


Assuntos
Artrite Psoriásica , COVID-19 , Psoríase , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artrite Psoriásica/mortalidade , COVID-19/epidemiologia , Pandemias , Psoríase/mortalidade , SARS-CoV-2 , Estados Unidos/epidemiologia
16.
J Am Chem Soc ; 144(23): 10582-10590, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35652187

RESUMO

High-entropy alloys (HEAs) are attracting intensive attention due to their broad compositional tunability and interesting catalytic properties. However, precisely shaping the HEAs into suprathin low-dimensional nanostructures for achieving diverse applications remains an enormous challenge owing to their intrinsic thermodynamic instability. Herein we propose a new and general low-temperature method for incorporating up to eight metallic elements into one single-phase subnanometer ribbon to achieve the thinnest HEA metal materials in the world. We experimentally demonstrate that synthetic processes for suprathin HEA subnanometer ribbons (SNRs) include (1) different metal atom nucleation via galvanic exchange reaction between different metal precursors and Ag nanowire template, (2) co-reduction of different metal precursors on nanowire template, and (3) the removal of the inner Ag core. Density functional theory (DFT) calculations reveal that the crystallization and stabilization of HEA SNRs strongly depend on the "highly dynamic" Ag from the template, and the crystallization levels of HEA subnanometer ribbons are closely correlated with the concentration of Pt and Pd. We demonstrate that the present synthetic method enables the flexible control of components and concentrations in HEAs SNRs for achieving a library of HEA SNRs and also superior electrocatalytic properties. The well-designed HEA SNRs show great improvement in catalyzing the oxygen reduction reaction of fuel cells and also high discharge capacity, low charge overpotential, and excellent durability for Li-O2 batteries. DFT calculations reveal the superior electrochemical performances are attributed to the strong reduction capability from high-concentration reductive elements in HEAs, while the other elements guarantee the site-to-site efficient electron transfer.

17.
Angiogenesis ; 25(1): 71-86, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34170441

RESUMO

Aberrant variations in angiogenesis have been observed in tumor tissues with abnormal stiffness of extracellular matrix (ECM). However, it remains largely unclear how ECM stiffness influences tumor angiogenesis. Numerous studies have reported that vascular endothelial growth factor-A (VEGF-A) released from tumor cells plays crucial roles in angiogenesis. Hence, we demonstrated the role of ECM stiffness in VEGF-A release from neuroblastoma (NB) cells and the underlying mechanisms. Based on 17 NB clinical samples, a negative correlation was observed between the length of blood vessels and stiffness of NB tissues. In vitro, an ECM stiffness of 30 kPa repressed the secretion of VEGF165 from NB cells which subsequently inhibited the tube formation of human umbilical vein endothelial cells (HUVECs). Knocked down VEGF165 in NB cells or blocked VEGF165 with neutralizing antibodies both repressed the tube formation of HUVECs. Specifically, 30 kPa ECM stiffness repressed the expression and nuclear accumulation of Yes-associated protein (YAP) to regulate the expression of Serine/Arginine Splicing Factor 1 (SRSF1) via Runt-related transcription factor 2 (RUNX2), which may then subsequently induce the expression and secretion of VEGF165 in NB tumor cells. Through implantation of 3D col-Tgels with different stiffness into nude mice, the inhibitory effect of 30 kPa on NB angiogenesis was confirmed in vivo. Furthermore, we found that the inhibitory effect of 30 kPa stiffness on NB angiogenesis was reversed by YAP overexpression, suggesting the important role of YAP in NB angiogenesis regulated by ECM stiffness. Overall, our work not only showed a regulatory effect of ECM stiffness on NB angiogenesis, but also revealed a new signaling axis, YAP-RUNX2-SRSF1, that mediates angiogenesis by regulating the expression and secretion of VEGF165 from NB cells. ECM stiffness and the potential molecules revealed in the present study may be new therapeutic targets for NB angiogenesis.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Neovascularização Patológica/metabolismo , Neuroblastoma , Fatores de Processamento de Serina-Arginina/metabolismo , Fatores de Transcrição/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Matriz Extracelular , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Nus , Neovascularização Patológica/genética , Neuroblastoma/irrigação sanguínea , Fator A de Crescimento do Endotélio Vascular/genética
18.
BMC Ophthalmol ; 22(1): 513, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36577987

RESUMO

BACKGROUND: The main barriers keeping individuals with high-risk of angle closure from seeking eye-care service are the absence of both disease awareness and convenient and low-cost access to the ocular health care system. Present study described the efficacy of a health examination center-based screening model designed to detect eyes with high risk of angle closure (HRAC) among healthy individuals using anterior segment optical coherence tomography (AS-OCT). METHODS: From March 1 to April 30, 2017, consecutive individuals aged ≥ 40 years undergoing routine physical examinations at a health examination center were invited to enroll. Presenting visual acuity (PVA), intraocular pressure (IOP) measurement, non-mydriatic fundus photography and AS-OCT were performed by three trained nurses. Participants with PVA < 6/12 in the better-seeing eye, IOP ≥ 24 mmHg, or abnormal fundus photography in either eye were referred to the outpatient clinic, but not included in the analysis. Eyes with HRAC were defined as having trabecular-iris angle < 12 degrees in ≥ 3 quadrants. Configuration of the iris was classified into flat, bowing, bombe, thick peripheral iris and mixed mechanism. RESULTS: Altogether, 991 participants (77.3%) with readable OCT images (mean age 55.5 ± 9.0 years; 58.4% men) were included. HRAC was diagnosed in 78 eyes (7.9%, 61.3 ± 8.2 years, 41.0% men). The prevalence of HRAC increased with age (p < 0.001) and was much higher among women (11.2%) than men (5.5%) (p = 0.001). The mixed mechanism iris configuration was most common among eyes with HRAC (37/78, 47.4%). CONCLUSION: HRAC is prevalent among asymptomatic Chinese adults undergoing routine health screening. Health examination center-based eye screening with AS-OCT administered by non-specialists may be a good model to screen narrow angles in the population at large.


Assuntos
Glaucoma de Ângulo Fechado , Tomografia de Coerência Óptica , Masculino , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Tomografia de Coerência Óptica/métodos , Pressão Intraocular , Glaucoma de Ângulo Fechado/diagnóstico , Gonioscopia , Iris/diagnóstico por imagem , Segmento Anterior do Olho/diagnóstico por imagem
19.
Nano Lett ; 21(10): 4262-4269, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33962514

RESUMO

Single-atom catalysts (SACs) exhibit great potential in heterogeneous catalysis. However, the achievement of obtaining high-loading SACs remains a bottleneck. Herein, we first demonstrate a unique gas-migration, trapping, and emitting strategy for building a kind of Cd-based SAC for CO2 reduction (CO2RR). The gas-migration and trapping processes (≤750 °C) endows the material with an ultrahigh Cd loading amount of 30.3 wt %, while the emitting process can facilely modulate the loading amount from 30.3 to 1.4 wt %. For the CO2RR, the Cd-NC SACs with a loading amount of 18.4 wt % exhibits the maximum Faraday efficiency of 91.4% for CO at -0.728 V. The operando infrared spectroscopy studies prove the presence of main intermediates *COO-, *COOH, and *CO on Cd-NC-5M SACs during the catalytic process, indicating that the CO2RR follows the proton-decoupled electron-transfer mechanism. Density functional theory simulations reveal that the Cd-N4 structure reduces the Gibbs free energy of the rate-determining step (the hydrogenation step of *COOH).

20.
J Am Chem Soc ; 143(29): 10822-10827, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34279921

RESUMO

The electrosynthesis of high-value-added multicarbon compounds coupled with hydrogen production is an efficient way to achieve carbon neutrality; however, the lack of effective bifunctional catalysts in electrosynthesis largely hinders its development. Herein, we report the first example on the highly efficient electrosynthesis of high-value-added 1,1-diethoxyethane (DEE) at the anode and high-purity hydrogen at the cathode using 1 nm PtIr nanowires (NWs) as the bifunctional catalysts. We demonstrate that the cell using 1 nm PtIr nanowires as the bifunctional catalysts can achieve a reported lowest voltage of 0.61 V to reach the current density of 10 mA cm-2, much lower than those of the Pt NWs (0.85 V) and commercial Pt/C (0.86 V), and also can have the highest Faraday efficiencies of 85% for DEE production and 94.0% for hydrogen evolution in all the reported electrosynthesis catalysts. The in situ infrared spectroscopy study reveals that PtIr NWs can facilitate the activation of O-H and C-H bonds in ethanol, which is important for the formation of acetaldehyde intermediate, and finally DEE. In addition, the cell using PtIr NWs as bifunctional catalysts exhibits excellent stability by showing almost no obvious decrease in the Faraday efficiency of the DEE production.

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