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Hydrogen production through hydrogen evolution reaction (HER) offers a promising solution to combat climate change by replacing fossil fuels with clean energy sources. However, the widespread adoption of efficient electrocatalysts, such as platinum (Pt), has been hindered by their high cost. In this study, we developed an easy-to-implement method to create ultrathin Pt nanomembranes, which catalyze HER at a cost significantly lower than commercial Pt/C and comparable to non-noble metal electrocatalysts. These Pt nanomembranes consist of highly distorted Pt nanocrystals and exhibit a heterogeneous elastic strain field, a characteristic rarely seen in conventional crystals. This unique feature results in significantly higher electrocatalytic efficiency than various forms of Pt electrocatalysts, including Pt/C, Pt foils, and numerous Pt single-atom or single-cluster catalysts. Our research offers a promising approach to develop highly efficient and cost-effective low-dimensional electrocatalysts for sustainable hydrogen production, potentially addressing the challenges posed by the climate crisis.
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Antibiotics have attracted global attention because of their potential ecological and health risks. The emission, multimedia fate and risk of 18 selected antibiotics in the entire Yangtze River basin were evaluated by using a level â £ fugacity model. High antibiotic emissions were found in the middle and lower reaches of the Yangtze River basin. The total antibiotic emissions in the Yangtze River basin exceeded 1600 tons per year between 2013 and 2021. The spatial distribution of antibiotics concentration was the upper Yangtze River > middle Yangtze River > lower Yangtze River, which is positively correlated with animal husbandry size in the basin. Temperature and precipitation increases may decrease the antibiotic concentrations in the environment. Transfer fluxes showed that source emission inputs, advection processes, and degradation fluxes contributed more to the total input and output. High ecological risks in the water environment were found in 2018, 2019, 2020, and 2021. The comprehensive health risk assessment through drinking water and fish consumption routes showed that a small part of the Yangtze River basin is at medium risk, and children have a relatively high degree of health risk. This study provides a scientific basis for the pollution control of antibiotics at the basin scale.
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Rios , Poluentes Químicos da Água , Animais , Criança , Humanos , Antibacterianos/análise , Multimídia , Monitoramento Ambiental , China , Medição de Risco , Poluentes Químicos da Água/análiseRESUMO
The increasing number of coronavirus disease 2019 (COVID-19) infections have highlighted the long-term consequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection called long COVID. Although the concept and definition of long COVID are described differently across countries and institutions, there is general agreement that it affects multiple systems, including the immune, respiratory, cardiovascular, gastrointestinal, neuropsychological, musculoskeletal, and other systems. This review aims to provide a synthesis of published epidemiology, symptoms, and risk factors of long COVID. We also summarize potential pathophysiological mechanisms and biomarkers for precise prevention, early diagnosis, and accurate treatment of long COVID. Furthermore, we suggest evidence-based guidelines for the comprehensive evaluation and management of long COVID, involving treatment, health systems, health finance, public attitudes, and international cooperation, which is proposed to improve the treatment strategies, preventive measures, and public health policy making of long COVID.
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COVID-19 , Humanos , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda , Fatores de RiscoRESUMO
Taipu River is an important transboundary river and drinking water source in the Yangtze River Delta, China. This study collected 15 topsoil samples along the Taipu River banks and subsequently determined the polycyclic aromatic hydrocarbons (PAHs) concentrations, sources, and ecological and health risks. The sum of toxic 15 PAHs concentrations ranged from 83.13 to 28342.53 ng/g, with a mean of 2828.69 ng/g. High molecular weight (HMW) PAHs were the dominant components and Indene (1,2,3, -cd) benzopyrene (InP) accounted for the highest proportion in individuals. The average PAH concentration in residential land was the highest, followed by those in industrial and agricultural land. The PAH concentration was positively related to contents of total carbon, total nitrogen, ammonium nitrogen, and aminopeptidase activity in soils. The mixed combustion of biomass, coal, and petroleum and traffic emissions could be the primary PAH contributors. The total PAHs at over half of sampling points had relatively high risk quotients and incremental lifetime cancer risk (ILCR) values, posing potential or great ecological threats and health risks.
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Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios , Solo , Medição de Risco , ChinaRESUMO
The rapid growth of malware has become a serious problem that threatens the security of the mobile ecosystem and needs to be studied and resolved. Android is the main target of attackers due to its open source and popularity. To solve this serious problem, an accurate and efficient malware detection method is needed. Most existing methods use a single type of feature, which can be easily bypassed, resulting in low detection accuracy. In addition, although multiple types of features are used in some methods to solve the drawbacks of detection methods using a single type of feature, there are still some problems. Firstly, due to multiple types of features, the number of features in the initial feature set is extremely large, and some methods directly use them for training, resulting in excessive overhead. Furthermore, some methods utilize feature selection to reduce the dimensionality of features, but they do not select highly distinguishable features, resulting in poor detection performance. In this article, an effective and accurate method for identifying Android malware, which is based on an analysis of the use of seven types of static features in Android is proposed to cope with the rapid increase in the amount of Android malware and overcome the drawbacks of detection methods using a single type of feature. Instead of utilizing all extracted features, we design three levels of feature selection methods to obtain highly distinguishable features that can be effective in identifying malware. Then a fully densely connected convolutional network based on DenseNet is adopted to leverage features more efficiently and effectively for malware detection. Compared with the number of features in the original feature set, the number of features in the feature set obtained by the three levels of feature selection methods is reduced by about 97%, but the accuracy is only reduced by 0.45%, and the accuracy is more than 99% in a variety of machine learning methods. Moreover, we compare our detection method with different machine learning models, and the experimental results show that our method outperforms general machine learning models. We also compare the performance of our detection method with two state-of-the-art neural networks. The experimental results show that our detection model can greatly reduce the training cost and still achieve good detection performance, reaching an accuracy of 99.72%. In addition, we compare our detection method with other similar detection methods that also use multiple types of features. The results show that our detection method is superior to the comparison methods.
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Adaptação Psicológica , Ecossistema , Efeitos Psicossociais da Doença , Aprendizado de Máquina , Redes Neurais de ComputaçãoRESUMO
In this study, 50 surface water and sediment samples were collected from 25 sampling points in Qingpu District (including Taipu River basin, Jinze Reservoir, and Qingxi country park) in the Yangtze River Delta integration demonstration area, and 22 pharmaceuticals and personal care products (PPCPs) in the samples were analyzed using high-performance liquid chromatography tandem mass spectrometry (HPLC/MS-MS). The distribution characteristics, sources, and influencing factors of targeted PPCPs in the study area were studied in detail. The ecological and health risks of the target PPCPs were evaluated using the quotients method. The results showed that a total of 19 PPCPs were detected in the surface water and sediment samples from 25 sampling points in Qingpu District, with total concentrations ranging from 0.06 to 178.67 ng·L-1 and 0.07 to 37.68 ng·g-1, respectively. The average value of sulfachloropyridazine (SCP) in the surface water was the highest with a concentration of 129.54 ng·L-1, whereas the average value of sulfamethoxazole (SMX) in the sediment was the highest with a concentration of 70.62 ng·g-1. The spatial distribution of the total amount of PPCPs showed a trend of Qingxi country park > Jinze Reservoir > Taipu River basin. Principal component analysis showed that the main sources of pollution were animal antibiotics used in aquaculture and the discharge of domestic sewage. There was a significant correlation between lg Koc and lg Kd (P<0.05), indicating that the organic carbon plays an important role in the distribution of the target PPCPs in water and sediments. The ecological risk assessment results revealed that the fungicides (TCC and TCS) in the surface waters showed a moderate risk to aquatic organisms of different trophic levels. The Qingxi country park and Jinze Reservoir were the regions with the highest ecological risks of PPCPs in surface water and sediment. The health risk entropy (HQ) of people of all age groups exposed through drinking was less than 1; however, with the continuous emission and accumulation of PPCPs, the pollution control of PPCPs in the environment still requires further attention.
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Cosméticos , Preparações Farmacêuticas , Poluentes Químicos da Água , Animais , China , Cosméticos/análise , Monitoramento Ambiental , Humanos , Multimídia , Medição de Risco , Rios , Água , Poluentes Químicos da Água/análiseRESUMO
Due to the widespread consumption of antibiotics by humans and animals, antibiotic residues from human and animal excrements are released into the environment through domestic sewage and breeding wastewater, which ultimately affect the ecological environment and human health. In this study, the concentrations of 10 antibiotics in the air, water, soil, and sediment from 2013 to 2019 in Qingpu District of the integrated demonstration zone of the Yangtze River Delta were predicated by developing a dynamic Level IV fugacity model. The influence of seasonal environmental factors (e.g., temperature, rainfall) on the distribution and migration of antibiotics in multi-media was also explored. The simulation results show that the 10 antibiotics mainly existed in water and sediment. The concentrations of antibiotics in air, water, soil, and sediment were 0-7.629 × 10-14 ng/L, 1.187 × 10-10-16.793 ng/L, 1.042 × 10-14-3.500 × 10-11 ng/g and 8.015 × 10-12-14.188 ng/g, respectively. It was also found that the increase in temperature and rainfall can reduce the migration rate of some antibiotics into the water and sediment phases. The flux analysis of the cross-media migration and transformation of antibiotics in Qingpu District shows that advection was the prime input and output paths of antibiotics in the water. Moreover, the prime input and output paths of antibiotics in sediment were sedimentation from water to sediment and degradation. Sensitivity analysis shows that the characteristics of antibiotic emission, degradation rate, and Koc were the most influential parameters for target chemicals. The results of risk assessment based on Monte Carlo method reveal that the overall risk level of antibiotics in sediment was relatively risk-free, and the risk of antibiotics in water decreased in the order of tetracyclines > ß-lactams > fluoroquinolones > macrolides > sulfonamides.
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Rios , Poluentes Químicos da Água , Animais , Antibacterianos/análise , China , Monitoramento Ambiental , Humanos , Multimídia , Medição de Risco , Poluentes Químicos da Água/análiseRESUMO
Pharmaceutical compounds were emerging contaminants, and the accumulation of pharmaceutical compounds in the environment increased the risk to humans and ecosystems. In this study, electron beam irradiation was applied to degrade indomethacin (IDM) in aqueous solution. IDM degradation followed pseudo-first-order kinetics and 300 µM IDM could be completely degraded at only 2 kGy. According to the quenching experiment, the dose constant ratios of oxidative radicals (â¢OH) and reductive radicals (e-aq and â¢H) could be calculated as kâ¢OH: ke aq and â¢H=4.79:1. As the concentration of H2O2 increased from 0 to 10 mM, the dose constant increased from 1.883 to 2.582 kGy-1. However, degradation effect would be restrained in the existence of NO-3, NO-2, CO2-3, HCO-3, SO2-, and humic acid due to their competition for the active species. Theoretical calculation revealed the radical attacking sites of IDM molecule and the most probable pathways were proposed with identification of intermediates. The attack of â¢OH mainly resulted in the cleavage of amide bond, indole ring opening, demethoxylation, and â¢OH addition. Dechlorination and the reduction of the carbonyl group occurred on IDM molecular through the reduction of e-aq and â¢H. The intermediates could continue to be degraded to small molecule acid, such as formic acid, acetic acid, and oxalic acid. Furthermore, highly toxic IDM transformed into less toxic products during the irradiation process.
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Peróxido de Hidrogênio , Poluentes Químicos da Água , Ecossistema , Elétrons , Humanos , Peróxido de Hidrogênio/química , Indometacina/química , Cinética , Oxirredução , Poluentes Químicos da Água/análiseRESUMO
The dramatic growth of the sodium-ion battery market evokes a high demand for high-performance cathodes. In this work, a nanosized amorphous FePO4@rGO composite is developed using coprecipitation combined with low-temperature hydrothermal synthesis, which registered a surface area of 179.43 m2 g-1. The composites maintain three-dimensional mesoporous morphology with a pore size in the range of 3-4 nm. Uniform distribution of amorphous FePO4 allows a reversible capacity of 175.4 mA h g-1 at 50 mA g-1 while maintaining a stable cycle life of 500 cycles at 200 mA g-1. The amorphous FePO4@rGO, obtained by energy-efficient synthesis, significantly improved the rate performance compared to the crystalline material prepared at high temperatures. Cyclic voltammetry tests reveal that the fast reaction kinetics can be attributed to the pseudocapacitive behavior of the electrode. In addition, we demonstrated the promise of FePO4@rGO cathodes for low-temperature sodium-ion batteries.
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Virus diseases have been a great threat to production of economically important crops. In practice, the use of virus-free planting material is an effective strategy to control viral diseases. Cryotherapy, developed based on cryopreservation, is a novel plant biotechnology tool for virus eradication. Comparing to the traditional meristem culture for virus elimination, cryotherapy resulted in high efficiency of pathogen eradication. In general, cryotherapy includes seven major steps: (1) introduction of infected plant materials into in vitro cultures, (2) shoot tip excision, (3) tolerance induction of explants to dehydration and subsequent freezing in liquid nitrogen (LN), (4) a short-time treatment of explants in LN, (5) warming and post-culture for regeneration, (6) re-establishment of regenerated plants in greenhouse conditions, and (7) virus indexing.