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1.
Chem Commun (Camb) ; 60(58): 7499-7502, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-38946539

ABSTRACT

Designing electrocatalysts for seawater splitting remains challenging. A Ru-Co alloy supported by an N-doped carbon substrate catalyst has been designed using etching and a low-temperature treatment method. Studies show that the superior performance of this catalyst is related to the hollow-structured N-doped carbon frame and surface reconstruction of the Ru-Co alloy.

2.
Medicine (Baltimore) ; 100(18): e25837, 2021 May 07.
Article in English | MEDLINE | ID: mdl-33950996

ABSTRACT

BACKGROUND: There are large knowledge gaps regarding how transmission of 2019 novel coronavirus disease (COVID-19) occurred in different settings across the world. This study aims to summarize basic reproduction number (R0) data and provide clues for designing prevention and control measures. METHODS: Several databases and preprint platforms were retrieved for literature reporting R0 values of COVID-19. The analysis was stratified by the prespecified modeling method to make the R0 values comparable, and by country/region to explore whether R0 estimates differed across the world. The average R0 values were pooled using a random-effects model. RESULTS: We identified 185 unique articles, yielding 43 articles for analysis. The selected studies covered 5 countries from Asia, 5 countries from Europe, 12 countries from Africa, and 1 from North America, South America, and Australia each. Exponential growth rate model was most favored by researchers. The pooled global R0 was 4.08 (95% CI, 3.09-5.39). The R0 estimates for new and shifting epicenters were comparable or even higher than that for the original epicenter Wuhan, China. CONCLUSIONS: The high R0 values suggest that an extraordinary combination of control measures is needed for halting COVID-19.


Subject(s)
Basic Reproduction Number , COVID-19/epidemiology , Global Health , Pneumonia, Viral/epidemiology , Humans , Pandemics , Pneumonia, Viral/virology , SARS-CoV-2
3.
PLoS One ; 15(12): e0244083, 2020.
Article in English | MEDLINE | ID: mdl-33370326

ABSTRACT

OBJECTIVE: The answer to this article lies in: Does the financial activities of physical enterprises have an adverse impact on their main business? Is it conducive to the sustainable development of the national economy? However, when most scholars study the impact of environmental regulations on companies performance, they have not classified companies performance. This article will study the relationship between environmental regulations and performance levels based on the classification of companies performance, and then divide the nature of industry pollution, companies location and nature of property for in-depth research. METHODS: First, this article uses a random effect variable-intercept model to measure companies financial performance and non-financial performance. Then, the variables are divided into two variable groups: light pollution and heavy pollution according to the nature of industry pollution. Next, the companies are divided into three variable groups: the eastern region, the central region, and the western region. Finally, the company is divided into two variable groups: state-owned and non-state-owned according to the nature of property. CONCLUSIONS: The study found that: (1) Environmental regulations have inhibited companies financial activities. And the inhibitory effect of environmental regulations on the financial performance of enterprises is more obvious in the heavily polluting industries and enterprises in central and eastern regions. (2) Environmental regulations and companies non-financial performance are also negatively related, environmental regulations have also inhibited the non-financial performance of companies, this effect is more pronounced in heavily polluting industries and enterprises in western regions. (3) Income crowding effect brought by China's environmental regulations is greater than the income compensation effect brought by stimulating technological innovation.


Subject(s)
Commerce/legislation & jurisprudence , Conservation of Natural Resources/legislation & jurisprudence , Environmental Pollution/prevention & control , Inventions/legislation & jurisprudence , Sustainable Development/legislation & jurisprudence , China , Commerce/economics , Conservation of Natural Resources/economics , Humans , Inventions/economics , Sustainable Development/economics
4.
Int J Biometeorol ; 63(1): 51-60, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30382350

ABSTRACT

Accumulating evidence suggests that air pollution is a risk factor for adverse respiratory and cardiovascular health outcomes. However, the different impacts of exposure to air pollutants on influenza virus activity and influenza-like illness (ILI) have not been well documented in epidemiological studies. We examined the association between air pollutants of particular matters < 2.5 µm (PM2.5), particular matters < 10 µm (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), and influenza occurrences in Hefei, China, from December 2013 to December 2015 by generalized Poisson additive regression models. The result suggested that PM2.5 and PM10 had similar effects on clinical ILI and influenza incidence. PM10 was negatively associated with clinical ILI (relative risk (RR) 0.980, 95% confidence interval (CI) 0.974-0.987), while PM2.5 were positively associated with clinical ILI (RR 1.040; 95% CI 1.032-1.049). RRs for the laboratory-confirmed cases of influenza were 0.813 (95% CI, 0.755-0.875) for PM10 and 1.216 (95% CI, 1.134-1.304) for PM2.5. Nevertheless, the impacts of SO2 and NO2 on ILI and influenza were distinct. SO2 had significant influence on laboratory-confirmed influenza and had no significant linear relationship with ILI. NO2 was negatively correlated with influenza but had no obvious effect on clinical ILI cases. The present study contributes novel evidence on understanding of the effects of various air pollutants on influenza activities, and these findings can be useful and important for the development of influenza surveillance and early warning systems.


Subject(s)
Air Pollutants/analysis , Influenza, Human/epidemiology , China/epidemiology , Cities/epidemiology , Clinical Laboratory Techniques , Environmental Exposure/analysis , Humans , Incidence , Influenza, Human/diagnosis , Nitrogen Dioxide/analysis , Particulate Matter/analysis , Sulfur Dioxide/analysis
5.
Sci Rep ; 7(1): 17534, 2017 12 13.
Article in English | MEDLINE | ID: mdl-29235535

ABSTRACT

Influenza seasonality study is critical for policy-makers to choose an optimal time for influenza vaccination campaign, especially for subtropical regions where influenza seasonality and periodicity are unclear. In this study, we explored the seasonality and periodicity of influenza in Hefei, China during 2010 to 2015 using five proxies originated from three data sources of clinical surveillance of influenza-like illness (ILI), laboratory surveillance of influenza and death registration of pneumonia and influenza. We combined both wavelets analysis and de-linear-trend regression with Fourier harmonic terms to estimate seasonal characteristics of epidemic phase, peak time, amplitude, ratio of dominant seasonality. We found both annual cycle of influenza epidemics peaking in December-February and semi-annual cycle peaking in December-February and June-July in subtropical city Hefei, China. Compared to proxies developed by ILI and death registration data separately, influenza proxies incorporated laboratory surveillance data performed better seasonality and periodicity, especially in semi-annual periodicity in Hefei. Proxy of ILI consultation rate showed more timeliness peak than other proxies, and could be useful in developing the early warning model for influenza epidemics. Our study suggests to integrate clinical and laboratory surveillance of influenza for future influenza seasonality studies in subtropical regions.


Subject(s)
Influenza, Human/epidemiology , Seasons , China/epidemiology , Cities , Epidemics , Humans , Pneumonia/epidemiology , Regression Analysis , Time Factors , Wavelet Analysis
6.
Int J Infect Dis ; 57: 54-60, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28167255

ABSTRACT

OBJECTIVES: The aim of this study was to use a quasi-Poisson regression model to estimate the mortality burden associated with influenza type/subtypes in a subtropical city in China, for the years 2010-2015. METHODS: Quasi-Poisson models were fitted separately to weekly numbers of deaths from various causes. The exploratory variables were products of weekly proportions of specimens positive for influenza type/subtypes and weekly influenza-like illness consultation rates to represent influenza activity. Adjustments were made for long-term and seasonal trends, absolute humidity, and population size as confounding factors in the models. Excess deaths associated with influenza were regarded as the measurement for disease burden of influenza. RESULTS: The excess mortality for all-cause death associated with influenza was 9.9 per 100000 population in Hefei, with influenza A(H3N2) virus having the highest excess mortality rate, followed by influenza A(H1N1) virus and influenza B virus. Following the 2009 H1N1 pandemic, the highest excess mortality rate associated with influenza for different causes was consistently found in the year 2014, with the excess mortality rate for all-cause death reaching 17.47 per 100000 population. The sex differences in influenza-associated mortality were not statistically significant (p>0.05). CONCLUSIONS: The mortality burden of influenza has been substantial in Hefei since the 2009 influenza pandemic, while the evidence on sex differences in mortality burden is limited. The severity profile of influenza type/subtypes in China needs to be assessed and confirmed in more cities in future studies.


Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza, Human/mortality , Pandemics , China/epidemiology , Female , Humans , Influenza A Virus, H3N2 Subtype , Influenza B virus , Influenza, Human/epidemiology , Male , Seasons
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