1,257 research outputs found

    Au/Pb Interface Allows Methane Formation Pathway in Carbon Dioxide Electroreduction

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    The electrochemical conversion of carbon dioxide (CO2) to high-value chemicals is an attractive approach to create an artificial carbon cycle. Tuning the activity and product selectivity while maintaining long-term stability, however, remains a significant challenge. Here, we study a series of Au-Pb bimetallic electrocatalysts with different Au/Pb interfaces, generating carbon monoxide (CO), formic acid (HCOOH), and methane (CH4) as CO2 reduction products. The formation of CH4 is significant because it has only been observed on very few Cu-free electrodes. The maximum CH4 formation rate of 0.33 mA cm(-2) was achieved when the most Au/Pb interfaces were present. In situ Raman spectroelectrochemical studies confirmed the stability of the Pb native substoichiometric oxide under the reduction conditions on the Au-Pb catalyst, which seems to be a major contributor to CH4 formation. Density functional theory simulations showed that without Au, the reaction would get stuck on the COOH intermediate, and without O, the reaction would not evolve further than the CHOH intermediate. In addition, they confirmed that the Au/Pb bimetallic interface (together with the subsurface oxygen in the model) possesses a moderate binding strength for the key intermediates, which is indeed necessary for the CH4 pathway. Overall, this study demonstrates how bimetallic nanoparticles can be employed to overcome scaling relations in the CO2 reduction reaction

    Composition-Dependent Electrocatalytic Behavior of Au–Sn Bimetallic Nanoparticles in Carbon Dioxide Reduction

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    Bimetallic electrocatalysts offer great flexibility to tailor the activity and selectivity in electrochemical carbon dioxide (CO2) reduction. Here, we report on the electrocatalytic behavior of Au-Sn bimetallic nanoparticles with different intermetallic phases toward CO2 electroreduction. Two high-value products formed with reasonable current density: formic acid in the liquid phase and syngas (CO + H-2) in the gas phase. Notably, the phase composition of the catalysts had a massive influence on both activity and product distribution. Selective isotopic labeling studies emphasized the role of bicarbonate as the source of CO and formic acid formation on the AuSn bimetallic phase. In situ Raman spectroelectrochemical studies also demonstrated that the catalytic performance of the AuSn phase was superior to that of its parent metal and other bimetallic counterparts. The achieved control over the product distribution demonstrated the promise of bimetallic nanostructures being employed as efficient catalysts in the electroreduction of CO2

    Menopausal hormone therapy and risk of venous thromboembolism: the story so far

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    Menopausal hormone therapy (MHT) is known to increase the risk of venous thromboembolism (VTE), which includes deep vein thrombosis, pulmonary embolism, and less frequently cerebral vein thrombosis, but the absolute risk for a given patient is very low. After starting MHT, the risk of VTE seems to be at its highest, declining to the non-HRT user baseline level of risk after stopping. Whether estrogen-only or estrogen-progestin HRT combination is linked to a similar risk of VTE is unclear from the available evidence. The aim of this study is to evaluate the risks of developing VTE in relation to different types as well as different modes of administration of MHT through a database search including PubMed, MEDLINE, Google Scholar, Cochrane Library, and others in order to provide the women carers with the up-to-date and evidence-based guidelines and recommendations while counseling the post-menopausal women enquiring on use of hormonal therapies either to alleviate the menopausal symptoms or to prevent the longterm sequelae of estrogen deficiency

    Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

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    Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

    The medical and biochemical knowledge of health care professionals regarding the management of MERS-CoV: lessons from 2019 pilgrimage season in Al-Madinah, Saudi Arabia: A cross-sectional study

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    Background: Middle East respiratory syndrome coronavirus (MERS-CoV) epidemic was a serious healthcare concern not responding to conventional anti-viral therapies between 2012 and 2017 with high fatality rates. Saudi Arabia is still among the best world examples in combating both MERS-CoV and COVID-19 pandemics. Objectives: Investigating the medical and biochemical knowledge of healthcare professionals in Al-Madinah, Saudi Arabia on preventive, diagnostic and therapeutic measures against MERS-CoV epidemic. Subjects and methods: In 2019, this cross-sectional study included 416 healthcare personnel of which 402 participants answered the questions with a response rate of 96.7%. Specialties of participants were medical students (1.4%), physicians (64.4%), nurses (23.6%) and others (10.7%). Results: The vast majority of the investigated healthcare personnel gave the right answers. 96.7% of the participants answered that washing hands using water helps prevent MERS-CoV. 90.8% of the participants answered that wearing a clean non-sterile long-sleeved gown and gloves does helps prevent MERS-CoV infection. 94.7% of participants answered that using alcohol-based hand rub helps prevent MERS-CoV infection. 92.03% of the participants thought that wearing protective equipment does help preventing MERS-CoV infection. 86.1% answered that there is no vaccine available against MERS-CoV infection and 86.1% answered that taking vaccines is suitable for preventing MERS-CoV infection. 90.04% of the participants answered that MERS-CoV patients should be diagnosed using PCR and 84.3% thought that the highest levels of anti-CoV antibodies are in abattoir workers while 87.8% thought that isolation of suspected cases helps preventing MERS-CoV infection. Conclusion: The investigated healthcare workers had a satisfactory knowledge on the preventive and therapeutic measures and biochemical knowledge against MERS-CoV epidemic at mass gatherings as pilgrimage season

    Global burden of chronic respiratory diseases and risk factors, 1990–2019: an update from the Global Burden of Disease Study 2019

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    Background: Updated data on chronic respiratory diseases (CRDs) are vital in their prevention, control, and treatment in the path to achieving the third UN Sustainable Development Goals (SDGs), a one-third reduction in premature mortality from non-communicable diseases by 2030. We provided global, regional, and national estimates of the burden of CRDs and their attributable risks from 1990 to 2019. Methods: Using data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, we estimated mortality, years lived with disability, years of life lost, disability-adjusted life years (DALYs), prevalence, and incidence of CRDs, i.e. chronic obstructive pulmonary disease (COPD), asthma, pneumoconiosis, interstitial lung disease and pulmonary sarcoidosis, and other CRDs, from 1990 to 2019 by sex, age, region, and Socio-demographic Index (SDI) in 204 countries and territories. Deaths and DALYs from CRDs attributable to each risk factor were estimated according to relative risks, risk exposure, and the theoretical minimum risk exposure level input. Findings: In 2019, CRDs were the third leading cause of death responsible for 4.0 million deaths (95% uncertainty interval 3.6–4.3) with a prevalence of 454.6 million cases (417.4–499.1) globally. While the total deaths and prevalence of CRDs have increased by 28.5% and 39.8%, the age-standardised rates have dropped by 41.7% and 16.9% from 1990 to 2019, respectively. COPD, with 212.3 million (200.4–225.1) prevalent cases, was the primary cause of deaths from CRDs, accounting for 3.3 million (2.9–3.6) deaths. With 262.4 million (224.1–309.5) prevalent cases, asthma had the highest prevalence among CRDs. The age-standardised rates of all burden measures of COPD, asthma, and pneumoconiosis have reduced globally from 1990 to 2019. Nevertheless, the age-standardised rates of incidence and prevalence of interstitial lung disease and pulmonary sarcoidosis have increased throughout this period. Low- and low-middle SDI countries had the highest age-standardised death and DALYs rates while the high SDI quintile had the highest prevalence rate of CRDs. The highest deaths and DALYs from CRDs were attributed to smoking globally, followed by air pollution and occupational risks. Non-optimal temperature and high body-mass index were additional risk factors for COPD and asthma, respectively. Interpretation: Albeit the age-standardised prevalence, death, and DALYs rates of CRDs have decreased, they still cause a substantial burden and deaths worldwide. The high death and DALYs rates in low and low-middle SDI countries highlights the urgent need for improved preventive, diagnostic, and therapeutic measures. Global strategies for tobacco control, enhancing air quality, reducing occupational hazards, and fostering clean cooking fuels are crucial steps in reducing the burden of CRDs, especially in low- and lower-middle income countries

    Global, regional, and national burden of hepatitis B, 1990-2019: a systematic analysis for the Global Burden of Disease Study 2019

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    Global, regional, and national incidence of six major immune-mediated inflammatory diseases: findings from the global burden of disease study 2019

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    BACKGROUND: The causes for immune-mediated inflammatory diseases (IMIDs) are diverse and the incidence trends of IMIDs from specific causes are rarely studied. The study aims to investigate the pattern and trend of IMIDs from 1990 to 2019. METHODS: We collected detailed information on six major causes of IMIDs, including asthma, inflammatory bowel disease, multiple sclerosis, rheumatoid arthritis, psoriasis, and atopic dermatitis, between 1990 and 2019, derived from the Global Burden of Disease study in 2019. The average annual percent change (AAPC) in number of incidents and age standardized incidence rate (ASR) on IMIDs, by sex, age, region, and causes, were calculated to quantify the temporal trends. FINDINGS: In 2019, rheumatoid arthritis, atopic dermatitis, asthma, multiple sclerosis, psoriasis, inflammatory bowel disease accounted 1.59%, 36.17%, 54.71%, 0.09%, 6.84%, 0.60% of overall new IMIDs cases, respectively. The ASR of IMIDs showed substantial regional and global variation with the highest in High SDI region, High-income North America, and United States of America. Throughout human lifespan, the age distribution of incident cases from six IMIDs was quite different. Globally, incident cases of IMIDs increased with an AAPC of 0.68 and the ASR decreased with an AAPC of −0.34 from 1990 to 2019. The incident cases increased across six IMIDs, the ASR of rheumatoid arthritis increased (0.21, 95% CI 0.18, 0.25), while the ASR of asthma (AAPC = −0.41), inflammatory bowel disease (AAPC = −0.72), multiple sclerosis (AAPC = −0.26), psoriasis (AAPC = −0.77), and atopic dermatitis (AAPC = −0.15) decreased. The ASR of overall and six individual IMID increased with SDI at regional and global level. Countries with higher ASR in 1990 experienced a more rapid decrease in ASR. INTERPRETATION: The incidence patterns of IMIDs varied considerably across the world. Innovative prevention and integrative management strategy are urgently needed to mitigate the increasing ASR of rheumatoid arthritis and upsurging new cases of other five IMIDs, respectively. FUNDING: The Global Burden of Disease Study is funded by the Bill and Melinda Gates Foundation. The project funded by Scientific Research Fund of Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital (2022QN38)

    Measuring routine childhood vaccination coverage in 204 countries and territories, 1980-2019 : a systematic analysis for the Global Burden of Disease Study 2020, Release 1

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    Background Measuring routine childhood vaccination is crucial to inform global vaccine policies and programme implementation, and to track progress towards targets set by the Global Vaccine Action Plan (GVAP) and Immunization Agenda 2030. Robust estimates of routine vaccine coverage are needed to identify past successes and persistent vulnerabilities. Drawing from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2020, Release 1, we did a systematic analysis of global, regional, and national vaccine coverage trends using a statistical framework, by vaccine and over time. Methods For this analysis we collated 55 326 country-specific, cohort-specific, year-specific, vaccine-specific, and dosespecific observations of routine childhood vaccination coverage between 1980 and 2019. Using spatiotemporal Gaussian process regression, we produced location-specific and year-specific estimates of 11 routine childhood vaccine coverage indicators for 204 countries and territories from 1980 to 2019, adjusting for biases in countryreported data and reflecting reported stockouts and supply disruptions. We analysed global and regional trends in coverage and numbers of zero-dose children (defined as those who never received a diphtheria-tetanus-pertussis [DTP] vaccine dose), progress towards GVAP targets, and the relationship between vaccine coverage and sociodemographic development. Findings By 2019, global coverage of third-dose DTP (DTP3; 81.6% [95% uncertainty interval 80.4-82 .7]) more than doubled from levels estimated in 1980 (39.9% [37.5-42.1]), as did global coverage of the first-dose measles-containing vaccine (MCV1; from 38.5% [35.4-41.3] in 1980 to 83.6% [82.3-84.8] in 2019). Third- dose polio vaccine (Pol3) coverage also increased, from 42.6% (41.4-44.1) in 1980 to 79.8% (78.4-81.1) in 2019, and global coverage of newer vaccines increased rapidly between 2000 and 2019. The global number of zero-dose children fell by nearly 75% between 1980 and 2019, from 56.8 million (52.6-60. 9) to 14.5 million (13.4-15.9). However, over the past decade, global vaccine coverage broadly plateaued; 94 countries and territories recorded decreasing DTP3 coverage since 2010. Only 11 countries and territories were estimated to have reached the national GVAP target of at least 90% coverage for all assessed vaccines in 2019. Interpretation After achieving large gains in childhood vaccine coverage worldwide, in much of the world this progress was stalled or reversed from 2010 to 2019. These findings underscore the importance of revisiting routine immunisation strategies and programmatic approaches, recentring service delivery around equity and underserved populations. Strengthening vaccine data and monitoring systems is crucial to these pursuits, now and through to 2030, to ensure that all children have access to, and can benefit from, lifesaving vaccines. Copyright (C) 2021 The Author(s). Published by Elsevier Ltd.Peer reviewe
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