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Generalized Functional Linear Models:Efficient Modeling for High-dimensional Correlated Mixture Exposures
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作者 Bingsong Zhang Haibin Yu +11 位作者 Xin Peng Haiyi Yan Siran Li Shutong Luo Renhuizi Wei Zhujiang Zhou Yalin Kuang Yihuan Zheng Chulan Ou Linhua Liu Yuehua Hu Jindong Ni 《Biomedical and Environmental Sciences》 2025年第8期961-976,共16页
Objective Humans are exposed to complex mixtures of environmental chemicals and other factors that can affect their health.Analysis of these mixture exposures presents several key challenges for environmental epidemio... Objective Humans are exposed to complex mixtures of environmental chemicals and other factors that can affect their health.Analysis of these mixture exposures presents several key challenges for environmental epidemiology and risk assessment,including high dimensionality,correlated exposure,and subtle individual effects.Methods We proposed a novel statistical approach,the generalized functional linear model(GFLM),to analyze the health effects of exposure mixtures.GFLM treats the effect of mixture exposures as a smooth function by reordering exposures based on specific mechanisms and capturing internal correlations to provide a meaningful estimation and interpretation.The robustness and efficiency was evaluated under various scenarios through extensive simulation studies.Results We applied the GFLM to two datasets from the National Health and Nutrition Examination Survey(NHANES).In the first application,we examined the effects of 37 nutrients on BMI(2011–2016 cycles).The GFLM identified a significant mixture effect,with fiber and fat emerging as the nutrients with the greatest negative and positive effects on BMI,respectively.For the second application,we investigated the association between four pre-and perfluoroalkyl substances(PFAS)and gout risk(2007–2018 cycles).Unlike traditional methods,the GFLM indicated no significant association,demonstrating its robustness to multicollinearity.Conclusion GFLM framework is a powerful tool for mixture exposure analysis,offering improved handling of correlated exposures and interpretable results.It demonstrates robust performance across various scenarios and real-world applications,advancing our understanding of complex environmental exposures and their health impacts on environmental epidemiology and toxicology. 展开更多
关键词 Mixture exposure modeling Functional data analysis High-dimensional data Correlated exposures Environmental epidemiology
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Associations between individuals’daily carbon footprints and exposures to air pollution,noise,and greenspace in space and time
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作者 Jianwei Huang Mei-Po Kwan 《Geography and Sustainability》 2025年第3期197-208,共12页
To mitigate the catastrophic impacts of climate change,many measures and strategies have been designed and implemented to encourage people to change their daily behaviors for a low-carbon society transition.However,mo... To mitigate the catastrophic impacts of climate change,many measures and strategies have been designed and implemented to encourage people to change their daily behaviors for a low-carbon society transition.However,most people generate carbon emissions through their daily activities in space and time.They are also exposed to multiple environmental factors(e.g.,air pollution,noise,and greenspace).Changing people’s behaviors to reduce carbon emissions can also influence their multiple environmental exposures and further influence their health outcomes.Thus,this study seeks to examine the associations between individuals’daily carbon footprints and their exposures to multiple environmental factors(i.e.,air pollution,noise,and greenspace)across different spa-tial and temporal contexts using individual-level data collected by portable real-time sensors,an activity-travel diary,and a questionnaire from four communities in Hong Kong.The results first indicated that individuals’car-bon footprints of daily activities varied across different spatial and temporal contexts,with home and nighttime having the highest estimated carbon footprints.We also found that activity carbon footprints have a positive asso-ciation with PM2.5,which is particularly strong at home and from morning to nighttime,and mixed associations with noise(positive at home and nighttime,while negative in other places and during travel,from morning to afternoon).Besides,carbon footprints also have consistent negative associations with shrubland and woodland across different spatial and temporal contexts.The findings can provide essential insights into effective measures for promoting the transition to a low-carbon society. 展开更多
关键词 Activity carbon footprints Individual-level data Portable real-time sensors Multiple environmental exposures Low-carbon society transition
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DNA methylation in the association between pesticide exposures and type 2 diabetes
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作者 Guang-Jun Zheng Zheng-Er Fang +6 位作者 Bi-Ying Zhou Lei Zuo Xia Chen Ming-Liang Liu Lei Yu Chun-Xia Jing Guang Hao 《World Journal of Diabetes》 2025年第2期237-245,共9页
BACKGROUND Numerous epidemiological studies have found that pesticide exposure is associated with the incidence of type 2 diabetes(T2D);however,the underlying mechanisms remain unknown.DNA methylation may play a role ... BACKGROUND Numerous epidemiological studies have found that pesticide exposure is associated with the incidence of type 2 diabetes(T2D);however,the underlying mechanisms remain unknown.DNA methylation may play a role in this process.AIM To identify the genes associated with pesticide exposure and T2D by reviewing the current literature.METHODS We systematically searched PubMed and Embase for relevant studies that examined the association between pesticide exposure and DNA methylation,and studies on DNA methylation and T2D through January 15,2024.RESULTS We identified six genes(Alu,CABLES1,CDH1,PDX1,PTEN,PTPRN2)related to pesticide exposure and T2D.We also suggested future research directions to better define the role of DNA methylation in the association between pesticide exposure and T2D.CONCLUSION DNA methylation of specific genes may play a vital role in the association between pesticide exposure and T2D. 展开更多
关键词 DNA methylation Pesticide exposure Type 2 diabetes GENE MECHANISMS
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Occupational exposures and colorectal cancers:A quantitative overview of epidemiological evidence 被引量:2
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作者 Enrico Oddone Carlo Modonesi Gemma Gatta 《World Journal of Gastroenterology》 SCIE CAS 2014年第35期12431-12444,共14页
A traditional belief widespread across the biomedical community was that dietary habits and genetic predisposition were the basic factors causing colorectal cancer.In more recent times,however,a growing evidence has s... A traditional belief widespread across the biomedical community was that dietary habits and genetic predisposition were the basic factors causing colorectal cancer.In more recent times,however,a growing evidence has shown that other determinants can be very important in increasing(or reducing) incidence of this malignancy.The hypothesis that environmental and occupational risk factors are associated with colorectal cancer is gaining ground,and high risks of colorectal cancer have been reported among workers in some industrial branches.The aim of this study was to investigate the epidemiologic relationship between colorectal cancer and occupational exposures to several industrial activities,by means of a scientific literature review and meta-analysis.This work pointed out increased risks of colorectal cancer for labourers occupied in industries with a wide use of chemical compounds,such as leather(RR = 1.70,95%CI:1.24-2.34),basic metals(RR = 1.32,95%CI:1.07-1.65),plastic and rubber manufacturing(RR = 1.30,95%CI:0.98-1.71 and RR = 1.27,95%CI:0.92-1.76,respectively),besides workers in the sector of repair and installation of machinery exposed to asbestos(RR = 1.40,95%CI:1.07-1.84).Based on our results,the estimated crude excess risk fraction attributable to occupational exposure ranged from about 11% to about 15%.However,homogeneous pattern of association between colorectal cancer and industrial branches did not emerge from this review. 展开更多
关键词 Colorectal cancer Occupational exposures Public health Chemical compounds Basic metals Meta analysis
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A wavelet approach of investing behaviors and their effects on risk exposures 被引量:1
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作者 Roman Mestre 《Financial Innovation》 2021年第1期498-535,共38页
Exposure to market risk is a core objective of the Capital Asset Pricing Model(CAPM)with a focus on systematic risk.However,traditional OLS Beta model estimations(Ordinary Least Squares)are plagued with several statis... Exposure to market risk is a core objective of the Capital Asset Pricing Model(CAPM)with a focus on systematic risk.However,traditional OLS Beta model estimations(Ordinary Least Squares)are plagued with several statistical issues.Moreover,the CAPM considers only one source of risk and supposes that investors only engage in similar behaviors.In order to analyze short and long exposures to different sources of risk,we developed a Time–Frequency Multi-Betas Model with ARMA-EGARCH errors(Auto Regressive Moving Average Exponential AutoRegressive Conditional Heteroskedasticity).Our model considers gold,oil,and Fama–French factors as supplementary sources of risk and wavelets decompositions.We used 30 French stocks listed on the CAC40(Cotations Assistées Continues 40)within a daily period from 2005 to 2015.The conjugation of the wavelet decompositions and the parameters estimates constitutes decision-making support for managers by multiplying the interpretive possibilities.In the short-run,(“Noise Trader”and“High-Frequency Trader”)only a few equities are insensitive to Oil and Gold fluctuations,and the estimated Market Betas parameters are scant different compared to the Model without wavelets.Oppositely,in the long-run,(fundamentalists investors),Oil and Gold affect all stocks but their impact varies according to the Beta(sensitivity to the market).We also observed significant differences between parameters estimated with and without wavelets. 展开更多
关键词 Risk exposures CAPM Multi-betas model Time-frequency analysis MODWT OIL GOLD
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Currency exposures of the oil and natural gas stock prices in the Hushen-300 stock market: A nonlinear model approach 被引量:1
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作者 Yap Teck Lee 《Chinese Business Review》 2008年第9期15-19,共5页
The paper embarks to investigate the relationship between currency risk and stock prices of the oil and natural gas exploitation industry in the value-weighted Hushen-300 stock market, by applying the standard Capital... The paper embarks to investigate the relationship between currency risk and stock prices of the oil and natural gas exploitation industry in the value-weighted Hushen-300 stock market, by applying the standard Capital Asset Pricing Model (CAPM) and nonlinear exchange rate exposure model to the Renminbi against US dollar. The results show that the currency exposure does vary in the oil-gas stock prices throughout the bull and bear market. The study suggests that the models of the equilibrium exchange rate exposure must be extended to considering the nonlinear exchange rate exposure, the regime periods of bull and bear market, and the industry types that is sensitive to the currency exposures. The nonlinear dynamic relationship between the exchange rate changes and the Chinese energy stock prices throughout the bull and bear market add to the recent empirical evidences that foreign exchange markets and stock markets are closely correlated. 展开更多
关键词 exchange rate exposures energy stock prices Hushen-300 stock market
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A Concise Review of Surgical exposures for Revision Knee Arthroplasty
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作者 Ashish Anand Raviraj Adala +2 位作者 Manish Kumar J. Vijay Kumar Srinivas Gautam Kodikal 《Surgical Science》 2012年第5期256-260,共5页
Revision knee arthroplasty is fraught with complications such as delayed wound healing, arthrofibrosis, increased chances of infection, instability and extensor mechanism disruption. The key to avoiding these complica... Revision knee arthroplasty is fraught with complications such as delayed wound healing, arthrofibrosis, increased chances of infection, instability and extensor mechanism disruption. The key to avoiding these complications is to handle the soft tissue with care and to have an adequate surgical exposure at the same time. As the number of revisions has gone up, there has been a renewed interest in getting the basics right to have an adequate surgical exposure. Numerous surgical approaches have been proposed and subsequently modified. We present a concise review of the various surgical approaches for a revision knee replacement. 展开更多
关键词 KNEE ARTHROPLASTY REVISION exposures
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Prediction of Yellowing of Polystyrene Materials under Natural Weathering Exposures
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作者 Caixia Li Peixing Li 《Applied Mathematics》 2024年第12期834-839,共6页
The polystyrene (PS) materials tend to yellow over time. The yellowing phenomenon is an indicator of the material’s reduced performance and structural integrity. In the natural environment, sunlight is a major contri... The polystyrene (PS) materials tend to yellow over time. The yellowing phenomenon is an indicator of the material’s reduced performance and structural integrity. In the natural environment, sunlight is a major contributor to the yellowing, and elevated temperatures can accelerate the chemical reactions that lead to yellowing. The natural environmental factors are difficult to control, making it challenging to predict the yellowing process accurately. In this paper, we established a model to quantify the relationship between the yellowing index and key factors, solar radiation and temperature, from outdoor monitored climatic data. The model is trained and tested by the datasets collected from atmospheric exposure test stations located in Guangzhou and Qionghai. Same kinds of PS materials were exposed to external natural environments at the stations for one year. The parameters were estimated by least squares method. The results indicated that the model fits training and testing datasets well with R2 of 0.980 and 0.985, respectively. 展开更多
关键词 POLYSTYRENE Ageing YELLOWING Least Squares Method Arrhenius Equation Natural Weathering exposures
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Effect of Long-Term Thermal Exposures on Tensile Behaviors of K416B Nickel-Based Superalloy 被引量:4
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作者 Mao-Kai Chen Jun Xie +6 位作者 De-Long Shu Gui-Chen Hou Shu-Ling Xun Jin-Jiang Yu Li-Rong Liu Xiao-Feng Sun Yi-Zhou Zhou 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2020年第12期1699-1708,共10页
The effect of long-term thermal exposure on the tensile behavior of a high W content nickel-based superalloy K416B was investigated.The microstructure and the deformation characteristics were observed by scanning elec... The effect of long-term thermal exposure on the tensile behavior of a high W content nickel-based superalloy K416B was investigated.The microstructure and the deformation characteristics were observed by scanning electron microscopy and transmission electron microscopy,and the phase transformation of the alloy during long-term thermal exposure was analyzed by X-ray diffraction patterns and differential thermal analysis.Results showed that after thermal exposure at 1000℃,the MC carbides in the K416 B alloy decomposed into M_(6)C.During tensile deformation,dislocations slipping inγmatrix crossed over the M_(6)C by Orowan bowing mechanism.With the increase of thermal exposure time,the secondary M_(6)C reduced greatly the yield strength of the alloy at room temperature.Meanwhile,the continuous distribution of the secondary M_(6)C with great brittleness in the grain boundary could become the main source of crack,which might change the fracture characteristic of the alloy from trans-granular to intergranular. 展开更多
关键词 K416B superalloy Thermal exposure Deformation mechanism Fracture characteristics
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Diesel engine exhaust exposures in two underground mines 被引量:1
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作者 Debia Maximilien Couture Caroline +5 位作者 Njanga Pierre-Eric Neesham-Grenon Eve Lachapelle Guillaume Coulombe Hugo Hallé Stéphane Aubin Simon 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第4期641-645,共5页
Exposure to diesel engine exhaust(DE) is a major concern in underground mines. It has been linked to cardiopulmonary diseases and is classified as a human carcinogen. The goal of this study is to assess DE exposures i... Exposure to diesel engine exhaust(DE) is a major concern in underground mines. It has been linked to cardiopulmonary diseases and is classified as a human carcinogen. The goal of this study is to assess DE exposures in workers at two underground gold mines, to compare exposure levels within and between the mines, and to compare different methods of measuring DE exposures, namely respirable combustible dust(RCD), elemental carbon(EC) and total carbon(TC). Ambient and personal breathing zone(PBZ) measurements were taken. Side-by-side monitoring of RCD and of the respirable fraction of EC and TC(EC_Rand TC_R) was carried out in the workers' breathing zone during full-shift work.Regarding ambient measurements, in addition to EC_R, TC_Rand RCD, a submicron aerosol fraction(less than 1 mm) of EC and TC was also sampled(EC_1and TC_1). Average ambient results of 240 mg/m^3 in RCD, 150 mg/m^3 in EC_Rand 210 mg/m^3 in TC_Rare obtained. Average PBZ results of 190 mg/m^3 in RCD,84 mg/m^3 in EC3Rand 150 mg/min TC_Rare obtained. Very good correlation is found between EC_Rand EC_1 with a Pearson correlation coefficient of 0.99(p < 0.01) calculated between the two logtransformed concentrations. No differences are reported between EC_Rand EC_1, nor between TC_Rand TC_1, since ratios are equal to 1.04, close to 1, in both cases. Highest exposures are reported for loadhaul-dump(LHD) and jumbo drill operators and conventional miners. Significant exposure differences are reported between mines for truck and LHD operators(p < 0.01). The average TC_R/EC_Rratio is 1.6 for PBZ results, and 1.3 for ambient results. The variability observed in the TC_R/EC_Rratio shows that interferences from non-diesel related organic carbon can skew the interpretation of results when relying only on TC data. 展开更多
关键词 Diesel exposure Underground mine Respirable combustible dust Elemental carbon Total carbon Diesel particulate matter Similar exposure groups
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Increased population exposures to extreme precipitation in Central Asia under 1.5℃ and 2℃ global warming scenarios 被引量:1
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作者 Wei Wei Shan Zou +4 位作者 Weili Duan Yaning Chen Shuai Li Takahiro Sayama Jianyu Zhu 《Geography and Sustainability》 CSCD 2024年第3期343-356,共14页
The increase in extreme precipitation(EP)may pose a serious threat to the health and safety of population in arid and semi-arid regions.The current research on the impact of EP on population in Central Asia(CA)is insu... The increase in extreme precipitation(EP)may pose a serious threat to the health and safety of population in arid and semi-arid regions.The current research on the impact of EP on population in Central Asia(CA)is insufficient and there is an urgent need for a comprehensive assessment.Hence,we opted for precipitation and temperature data under two Shared Socioeconomic Pathways(SSP2-4.5 and SSP5-8.5)from ten Global Climate Models(GCMs),which were obtained from the NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP-CMIP6).By integrating population data in 2020 and 2050(SSP2 and SSP5),we investigated the future changes in EP and population exposure in CA under 1.5℃and 2℃global warming scenarios(GWSs).Our analysis indicates that EP in CA is projected to increase with global warming.Under the SSP5-8.5,the maximum daily precipitation(Rx1day)exhibits an average response rate to global warming of 3.58%/K(1.99-4.06%/K).With rising temperatures,an increasing number of areas and populations in CA will be impacted by EP,especially in the Fergana valley.Approximately 25%of the population(land area)in CA is exposed to Rx1day with increases of more than 8.31%(9.32%)under 1.5℃GWS and 14.18%(13.25%)under 2℃GWS.Controlling temperature rise can be effective in reducing population exposures to EP.For instance,limiting the temperature increase to 1.5℃instead of 2℃results in a 2.79%(1.75%-4.59%)reduction in population exposure to Rx1day.Finally,we found that climate change serves as the predominant factor influencing the population exposure to EP,while the role of population redistribution,although relatively minor,should not be disregarded.Particularly for prolonged drought,the role of population redistribution manifests negatively. 展开更多
关键词 Extreme precipitation Global warming Population exposure Central Asia
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THE USE OF DNA ADDUCTS AS MEASURE OF ENVIRONMENTAL CHEMICAL EXPOSURES IN THE WORK PLACE.
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作者 Tong-man Ong 《癌变·畸变·突变》 CAS CSCD 1991年第S1期140-140,共1页
Workers in many occupational settings areexposed to toxic chemicals and/or chemicalmixtures.Many of these chemicals or theirmetabolites are electrophilic genotoxic agentsand potential carcinogens which can covalentlyb... Workers in many occupational settings areexposed to toxic chemicals and/or chemicalmixtures.Many of these chemicals or theirmetabolites are electrophilic genotoxic agentsand potential carcinogens which can covalentlybind to cellular nucleophiles such as DNA toform DNA adducts.DNA adducts,therefore, 展开更多
关键词 CHEMICALS DNA OCCUPATIONAL PLACE FOUNDRY EXPOSURE
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Occupational exposures to blood and body fluids (BBF): Assessment of knowledge, attitude and practice among health care workers in general hospitals in Lebanon
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作者 Ibtissam Sabbah Hala Sabbah +2 位作者 Sanaa Sabbah Hussein Akoum Nabil Droubi 《Health》 2013年第1期70-78,共9页
Healthcare workers (HCWs) who are employed in traditional health care workplaces face a serious danger that may threaten their life;it is their exposure to blood and body fluids (BBF). In Lebanon, the introduction of ... Healthcare workers (HCWs) who are employed in traditional health care workplaces face a serious danger that may threaten their life;it is their exposure to blood and body fluids (BBF). In Lebanon, the introduction of a hospital accreditation system has put a particular emphasis on staff safety, and on the evaluation of professional practice (EPP) programs. Methods: A cross-sectional survey was conducted amongst 277 HCWs working in 4 general hospitals in South Lebanon. Objective: 1) describe the prevalence and the risk factors for occupational exposure to BBF among HCWs;2) evaluate knowledge, attitude, and practices of HCW concerning blood-borne pathogens and adherence to universal safety precautions. Results: The mean age of the respondents was 32.14 years (SD = 10.33), 57.4% were females. 43.3% of HCWs expressed that they use gloves all the time for every activeity of care. 67.1% were aware that needles should not be recapped after use;registered nurses and nursing students were more aware than physicians and nursing assistants (nurse) in this subject. 30% of HCWs declared having had at least one occupational exposure to BBF;62.7% of all accidental exposure was reported to the department responsible for managing exposures. Percutaneous injuries were the most frequently reported. Vaccination coverage was 88.4% for hepatitis B, and 48.4% against influenza. The source patient was tested in 43.4% of reported BBF exposures. Accidental exposure to BBF was more frequent in older people (OR = 3.42;p = 0.03) and the more experienced. Subjects working in intensive care unit ward reported more exposure to BBF (OR = 3;p = 0.04). Participants incurring exposure to BBF resorted to different measures after the injury suggesting a lack of a uniform policy for post-exposure prophylaxis. Conclusion: Exposure to BBF represents an important and frequently preventable occupational hazard for HCWs in Lebanon that requires continuous EPP of HCWs, and a comprehensive approach for prevention and management. 展开更多
关键词 OCCUPATIONAL exposure to BLOOD and body fluids Evaluation of the Professional PRACTICE KNOWLEDGE ATTITUDE and Practices (KAP) Controlled Language Healthcare Workers
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Investigation of nanosecond-pulsed dielectric barrier discharge actuators with powered electrodes of different exposures
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作者 徐双艳 蔡晋生 练永生 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第9期97-106,共10页
Nanosecond-pulsed dielectric barrier discharge actuators with powered electrodes of different exposures were investigated numerically by using a newly proposed plasma kinetic model. The governing equations include the... Nanosecond-pulsed dielectric barrier discharge actuators with powered electrodes of different exposures were investigated numerically by using a newly proposed plasma kinetic model. The governing equations include the coupled continuity plasma discharge equation, drift-diffusion equation, electron energy equation, Poisson's equation, and the Navier–Stokes equations.Powered electrodes of three different exposures were simulated to understand the effect of surface exposure on plasma discharge and surrounding flow field. Our study showed that the fully exposed powered electrode resulted in earlier reduced electric field breakdown and more intensive discharge characteristics than partially exposed and rounded-exposed ones. Our study also showed that the reduced electric field and heat release concentrated near the right upper tip of the powered electrode. The fully exposed electrode also led to stronger shock wave, higher heating temperature, and larger heated area. 展开更多
关键词 powered dielectric exposed drift Stokes pulsed Navier breakdown earlier exposure
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Bisphenol A in Fluid and Powdered Milk Samples and Associated Child Dietary Exposures
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作者 Patrícia dos Santos Souza Thomas Manfred Krauss +1 位作者 André Victor Sartori Shirley de Mello Pereira Abrantes 《Journal of Environmental Protection》 2023年第8期603-615,共33页
Bisphenol A (BPA) is a synthetic chemical found in a wide range of consumer products and consumables that humans are exposed to. The aim of this study was to determine BPA contamination levels in 51 milk samples sold ... Bisphenol A (BPA) is a synthetic chemical found in a wide range of consumer products and consumables that humans are exposed to. The aim of this study was to determine BPA contamination levels in 51 milk samples sold in the Rio de Janeiro Metropolitan Region, Brazil. Bisphenol A was detected (≥limit of detection, LOD) in five of the analyzed samples (9.8%) and quantified (≥limit of quantification, LOQ) in two (3.8%). The estimated daily intake (EDI) for children aged up to 12 months ranged from 24.95 to 97.72 ng/kg body weight/day, lower than the established European Union tolerable daily intake value. Recent evidence, however, suggests that even low doses of endocrine disruptors such as BPA may pose potential health risks, even more so when exposure occurs at such an early life stage. 展开更多
关键词 Bisphenol A UHPLC-MS/MS QUECHERS Cow’s Milk Dietary Exposure Assessment
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Assessment of Radiation Hazard from External and Internal Exposures at Adham and Surroundings in KSA
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作者 Emad Mayudh Al Thobaiti Sadek Zeghib Maher M. T. Qutub 《Journal of Geoscience and Environment Protection》 2023年第6期50-75,共26页
Twenty-eight environmental samples (eight well water, sixteen granitic rocks and four soils) were collected from different parts of Adham governorate (Adham, Haqal and Al-Jaizah), to assess the radiological hazard and... Twenty-eight environmental samples (eight well water, sixteen granitic rocks and four soils) were collected from different parts of Adham governorate (Adham, Haqal and Al-Jaizah), to assess the radiological hazard and cancer risk from different perspectives. Adham is situated in a valley between two granitic mountain chains, where much of water supply for drinking, house use and irrigation comes from wells collecting water rains. The activity concentrations of naturally occurring <sup>40</sup>K, <sup>226</sup>Ra and <sup>232</sup>Th and radionuclides were measured by gamma-ray spectrometry for all samples using RGK-1, RGU-1 and RGTh-1, IAEA reference standards issued by the International Atomic Energy Agency, for detector efficiency calibration. The measured values were utilized to evaluate the internal and external exposures both outdoors and indoors. Different standard room models were adopted for this respect to evaluate the indoor gamma-rays exposure from construction materials as well as internal exposure to radon gas emanating from them. Radon concentration indoors, exceeded the upper reference level in dwellings set at 300 Bq/m<sup>3</sup> by the world health organization, in many scenarios. The mean value of the total excess lifetime cancer risk (due to external exposure from gamma-rays) was 2.29 × 10<sup>-3</sup>, above the world average value of 1.45 × 10<sup>-3</sup>. Furthermore, the measured radon concentrations in all water samples exceeded the EPA (Environmental Protection Agency) 11.1 Bq·L<sup>-1</sup> standard for drinking water, ranging from 12 to 38 Bq·L<sup>-1</sup> with a mean value of 27 Bq·L<sup>-1</sup>. The total annual effective dose (due to inhalation and ingestion) from radon in water, ranged from 58 to 192 μSv/y (for adults) exceeding the international permissible limit of 100 μSv/y, in seven out of eight samples. According to obtained results, the internal exposure from radon in directly used water from wells, might be the major reason of any suspected radiological health hazard especially in Haqal. The second reason might be the internal exposure from indoor radon gas inhalation in poorly ventilated dwellings. 展开更多
关键词 Radiation Hazard Cancer Risk Radon Exposure Environmental Radioactivity Gamma Spectrometry
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Assessment of Lead Exposures during Abrasive Blasting and Vacuuming in Ventilated Field Containments: A Case Study
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作者 Kevin Guth Marie Bourgeois Raymond Harbison 《Occupational Diseases and Environmental Medicine》 2022年第2期116-131,共16页
Painting contractors have struggled with implementation and assessment of lead exposure controls leading to persistently elevated blood lead levels in this high-risk group of workers. The objective of this study was t... Painting contractors have struggled with implementation and assessment of lead exposure controls leading to persistently elevated blood lead levels in this high-risk group of workers. The objective of this study was to assess the intensity of lead exposures based on commonly used air velocities inside field containment structures during abrasive blasting and vacuuming. Exposures were assessed over 14 days from April to July 2021 at a tainter gate and bridge lead paint removal project. Personal air samples, skin wipes, air velocity readings, and blood lead samples were collected. The geometric mean (GM) lead exposure for abrasive blasters and vacuumers was ≥4 × the OSHA Lead Permissible Exposure Limit (PEL) of 50 μg/m<sup>3</sup>. There was high variability in the personal lead exposures (Geometric standard deviation (GSD) 4.0 - 5.0). The GM hand wipe exposures exceeded a Dermal PEL of 500 μg/wipe (abrasive blaster 564 μg/wipe and vacuumer 754 μg/wipe). Residual lead was measured on workers’ hands in 67% of the post hand washing samples. Air velocities measured inside of the field containments ranged from 107 feet per minute to 229 feet per minute. The effect of air velocity on the concentration of lead on workers’ hands after work (F = 0.58, p = 0.35) and airborne lead concentration was not significant (F = 0.36, p = 0.48). Six of the eight workers’ blood lead levels increased after exposure to lead. There was a non-statistically significant relationship between lead remaining on workers’ hands after handwashing and an increase in blood lead level. This is the first study that assessed both ventilation flow rates used in the industrial painting industry and measurements of airborne and dermal (hands) lead exposures. For the projects evaluated, the collected exposure data indicate that air velocities frequently used in the industrial painting industry to ventilate field containment structures did not tend to prevent an increase in worker blood lead and were ineffective for adequately controlling elevated concentrations of airborne lead and preventing contact with workers’ hands. 展开更多
关键词 Occupational Lead Exposure Blood Lead Engineering/Work Practice Controls
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Surgical exposures of the distal humeral fractures: An anatomical study of the anterior, posterior, medial and lateral approaches 被引量:5
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作者 Zi-Zheng Wu Jian-Dong Wang +3 位作者 Xiao-Xi Ji Zhi-Jian Ma Jian-Hong Wu Qiu-Gen Wang 《Chinese Journal of Traumatology》 CAS CSCD 2018年第6期356-359,共4页
Purpose:Exposure of the articular surface is the key to the successful treatment of intra-articular fractures of distal humerus. Anterior, posterior olecranon osteotomy as well as medial and lateral approaches are the... Purpose:Exposure of the articular surface is the key to the successful treatment of intra-articular fractures of distal humerus. Anterior, posterior olecranon osteotomy as well as medial and lateral approaches are the four main approaches to the elbow. The aim of this study was to compare the exposure of distal articular surfaces of these surgical approaches.Methods:Twelve cadavers were used in this study. Each approach was performed on six elbows according to previously published procedures. After completion of each approach, the exposed articular surfaces were marked by inserting 0.5 mm K-wires along the margins. The elbow was then disarticulated and the exposed articular surfaces were painted. The distal humeral articular surfaces were then closely wrapped using a piece of fibre-glass screen net with meshes. The exposed articular surfaces and the total articular surfaces were calculated by counting the number of meshes, respectively.Results:The average percentages of the exposed articular surfaces for the anterior, posterior olecranon osteotomy, medial and lateral approaches were 45.7% ± 2.0%, 53.9% ± 7.1%, 20.6% ± 4.9% and 28.5% ± 6.3%, respectively.Conclusion:The anterior and posterior approaches provide greater exposures of distal humeral articular surface than the medial and lateral ones in the treatment of distal humeral fractures. 展开更多
关键词 Elbow exposures DISTAL HUMERUS fractures Surgical approach
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Exposures and risks of arsenic,cadmium,lead,and mercury in cocoa beans and cocoa-based foods:a systematic review 被引量:1
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作者 Ekpor Anyimah-Ackah Isaac W.Ofosu +1 位作者 Herman E.Lutterodt Godfred Darko 《Food Quality and Safety》 SCIE CSCD 2019年第1期1-8,共8页
Background:The World Health Organization has expressed concern about arsenic,cadmium,lead,and mercury as potentially harmful to human health.As such,the world body has called for appropriate preventive and interventio... Background:The World Health Organization has expressed concern about arsenic,cadmium,lead,and mercury as potentially harmful to human health.As such,the world body has called for appropriate preventive and interventionary measures.In response,food regulatory bodies including European Food Safety Authority are monitoring the levels of these heavy metals in cocoa and cocoa products.Objective:Therefore,the objective of this paper is to synthesize the latest relevant available peer-reviewed publications on arsenic,cadmium,lead,and mercury with a view to highlighting the gaps to encourage further research and informing industry.Materials and Methods:A systematic review was conducted using the European Food Safety Authority guide in PubMed database and the result was reported according to the PRISMA checklist.Results:The results show that processing may dilute or concentrate the levels of arsenic,cadmium,lead,and mercury,depending on processing factors including the product type,processing method,and raw materials.In addition,some products exceed the European Union and Chinese Maximum Contaminant Level and may pose risk.Furthermore,the findings show that the risk of heavy metal toxicities was higher among children relative to adults at the same exposure in cocoa-based products and that correcting risk estimates for bioavailability reduces the level of estimated risk.Conclusion:Therefore,the review concludes that further research is required to clarify the effect of processing on the level of these contaminants in specific cocoa-based foods.Moreover,conducting risk studies based on age groups and correcting for bioavailability of arsenic,cadmium,lead,and mercury enhance accuracy of risk estimates.Recommendations:The review,therefore,recommends that a value chain approach be adopted to assessing the levels,exposures,and risks of arsenic,cadmium,lead,and mercury in cocoa-based foods and the effect of processing on these levels. 展开更多
关键词 toxic heavy metals RISKS exposures hazards cocoa-based products.
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Contribution of ferroptosis and SLC7A11 to light-induced photoreceptor degeneration
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作者 Xiaoxu Huang Yumeng Zhang +9 位作者 Yuxin Jiang Tong Li Shiqi Yang Yimin Wang Bo Yu Minwen Zhou Guanran Zhang Xiaohuan Zhao Junran Sun Xiaodong Sun 《Neural Regeneration Research》 2026年第1期406-416,共11页
Progressive photoreceptor cell death is one of the main pathological features of age-related macular degeneration and eventually leads to vision loss.Ferroptosis has been demonstrated to be associated with retinal deg... Progressive photoreceptor cell death is one of the main pathological features of age-related macular degeneration and eventually leads to vision loss.Ferroptosis has been demonstrated to be associated with retinal degenerative diseases.However,the molecular mechanisms underlying ferroptosis and photoreceptor cell death in age-related macular degeneration remain largely unexplored.Bioinformatics and biochemical analyses in this study revealed xC^(–),solute carrier family 7 member 11-regulated ferroptosis as the predominant pathological process of photoreceptor cell degeneration in a light-induced dry age-related macular degeneration mouse model.This process involves the nuclear factor-erythroid factor 2-related factor 2-solute carrier family 7 member 11-glutathione peroxidase 4 signaling pathway,through which cystine depletion,iron ion accumulation,and enhanced lipid peroxidation ultimately lead to photoreceptor cell death and subsequent visual function impairment.We demonstrated that solute carrier family 7 member 11 overexpression blocked this process by inhibiting oxidative stress in vitro and in vivo.Conversely,solute carrier family 7 member 11 knockdown or the solute carrier family 7 member 11 inhibitor sulfasalazine and ferroptosis-inducing agent erastin aggravated H_(2)O_(2)-induced ferroptosis of 661W cells.These findings indicate solute carrier family 7 member 11 may be a potential therapeutic target for patients with retinal degenerative diseases including age-related macular degeneration. 展开更多
关键词 age-related macular degeneration ferroptosis light exposure damage oxidative stress pathway PHOTORECEPTOR programmed cell death solute carrier family 7 member 11(SLC7A11)
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