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Regional characteristics of cadmium intake in adult residents from the 4th and 5th Chinese Total Diet Study 全文
2020
Xiao, Gexin | Liu, Yang | Dong, Kylie Fei | Lu, Jiang
Cadmium (Cd) is a heavy metal known to be harmful to human health. The aim of this study was to analyze the regional characteristics of dietary Cd intake of adult male residents in different regions of China. The value of this research is to guide regional consumers to minimize Cd intake by adjusting diets for different food categories in various regions. Dietary Cd intake data is used from the 4th and 5th Chinese Total Diet Studies (CTDS). The 4th CTDS collected data from 12 provinces, covering about 50% of the Chinese population. The 5th CTDS collected data from 20 provinces, covering about 67% of the Chinese population. Over 200 kinds of foods were sampled and divided into 13 categories and organized by geographic information system (GIS) mapping. The results showed that firstly, the dietary Cd intake of Chinese residents has increased; secondly, the food groups with the highest Cd intake were cereals and vegetables; and thirdly, the main food group of dietary Cd intake in different regions is presented such as cereals in Sichuan, Jiangxi, Zhejiang, Guangdong, Fujian, and Guangxi and vegetables in Shanghai, Ningxia, and Heilongjiang. Lastly, the food product with the highest dietary Cd intake concentration was found to be nori in 5 provinces. The other notable foods, with Cd intake, included peanuts, rice, squid, cuttlefish, and mushrooms.
显示更多 [+] 显示较少 [-]Environmental degradation and population health outcomes: a global panel data analysis 全文
2020
Majeed, Muhammad Tariq | Ozturk, Ilhan
This study investigates the relationship between environmental degradation and population health using a global panel data of 180 countries from 1990 to 2016. The empirical analysis is conducted using fixed-effects approach based on Hausman test. Moreover, two-stage least squares (2SLS) and system-generalized method of moments (SGMM) are used to deal with the endogenous nature of environmental degradation. The indicators of life expectancy and infant mortality are used to measure population health, whereas environmental degradation is measured by CO₂ emissions. The empirical findings show that environmental degradation negatively influences population health outcomes. It implies that countries having a high level of environmental degradation experience low life expectancy and high infant mortality rates. Findings of the study suggest that health-related reforms need to be aligned with policies which ensure lower environmental degradation.
显示更多 [+] 显示较少 [-]Economics of energy and environmental efficiency: evidence from OECD countries 全文
2020
Iram, Robina | Zhang, Jijian | Erdogan, Seyfettin | Abbas, Qaiser | Mohsin, Muhammad
The purpose of this research is to determine the efficiency of energy usage and its role in carbon dioxide emissions (CI) and economic-environmental efficiency (EEE) for some countries Organization for Economic Co-operation and Development (OECD) economies. For environment quality assessment, data envelopment analysis (DEA) is used to assess the data cover the period from 2013 to 2017. In this study, primary energy consumption (PEC) and population are two basic inputs along with gross domestic product (GDP) and carbon dioxide emissions that are desirable and undesirable outputs, respectively. The practical outcomes illustrate that Brunei, Australia, Singapore, and Hong Kong are the most effective and efficient states for the 5 years periods (2013–2017) in terms of energy efficiency and to reduce emission of carbon dioxide. In addition, other states in the OECD region shows greater economic proficiency than environmental proficiency. Furthermore, the results shows that energy efficiency has strong bonding with carbon emissions; however there is a weaker association between economic-environmental efficiency. Thus, the attainment of optimal level of energy efficiency could be more pivotal than economic efficiency to improve environmental efficiency in countries from the OECD region.
显示更多 [+] 显示较少 [-]Status of research on hydrogen sulphide gas in Chinese mines 全文
2020
Tan, Bo | Shao, Zhuangzhuang | Wei, Hongyi | Yang, Guangyuan | Zhu, Xiaoman | Xu, Bin | Zhang, Feichao
In the process of coal mining, the abnormal gushing of hydrogen sulphide in mines poses a major threat to the health of coal miners and the safe production of mines, as these types of accidents have occurred in many coal-producing countries. China is the largest coal producer and consumer in the world and is one of the countries that are substantially affected by hydrogen sulphide in mines. Based on the existing studies, many investigators in China have conducted research on the actual situation in China and obtained some results. This paper summarizes the previous findings and the current status of hydrogen sulphide in Chinese mines, and predicts the direction of future development. In this paper, we discuss the cause, abnormal distribution, abnormal gushing and prevention and control measures for hydrogen sulphide in mines. In addition, this paper also evaluates the impact of the hydrogen sulphide in mines on the environment and health. This paper outlines a systematic research framework regarding hydrogen sulphide in mines and assesses the interrelationship between subtopics within this system framework. Currently, the scientific research on hydrogen sulphide in mines is not sufficient to meet the needs of the affected individuals Therefore, researchers must increase their efforts in this area to jointly address the challenge of analysing hydrogen sulphide in mines. In addition, we hope that this paper will provide some guidance for the study of hydrogen sulphide in mines.
显示更多 [+] 显示较少 [-]Towards understanding groundwater quality using hydrochemical and statistical approaches: case of shallow aquifer of Mahdia–Ksour Essaf (Sahel of Tunisia) 全文
2020
Hajji, Soumaya | Nasri, Ghada | Boughariou, Emna | Bahloul, Moez | Allouche, Nabila | Bouri, Salem
Understanding the controlling factor of groundwater quality could certainly enhance the promotion of the sustainable development of groundwater resources. In fact, during the last decades, the coastal aquifer of Mahdia–Ksour Essef that belongs to the semi-arid region of Tunisia has been marked by an increase of groundwater extraction for irrigation and water for drinking. Moreover, the water quality shows deterioration due to the septic tanks and intensive agricultural activities especially in the coastal side of the aquifer. This study aimed to (1) assess the water quality using Piper Diagram, Box Plot, ions scatter diagrams, (2) understand the processes of mineralization acquisition in the aquifer, and (3) identify the chemical processes and their spatial distribution in the study area. To solve these objectives, the multivariate statistical analysis such as multiple correspondence analysis and hydrochemical analysis was performed. Accordingly, two types of groundwater are identified through the hydrochemical analysis as Na-Cl and Ca-SO₄. According to multiple correspondence analysis, three water groups are determined (G1, G2, and G3). Indeed, the groundwater quality is controlled by the water-rock interactions and affected by the seawater intrusion and agricultural activities. The generated results would be helpful to provide a managing model highlighting the threatened locations. It could be considered as a basis for future monitoring programs that aspire to protect water resources.
显示更多 [+] 显示较少 [-]Larvicidal effect from different Annonaceae species on Culex quinquefasciatus 全文
2020
Maia, Débora Soares | Lopes, Camila Ferreira | Saldanha, Aline Aparecida | Silva, Nathália Lucca | Sartori, Ângela Lúcia Bagnatori | Carollo, Carlos Alexandre | Sobral, Marcos Guerra | Alves, Stênio Nunes | Silva, Denise Brentan | de Siqueira, João Máximo
The recent outbreaks of mosquito-borne diseases highlighted the pivotal importance of mosquito vector control in tropical areas worldwide. Several strategies have been developed to control vector populations and disease transmission in endemic areas. The steps to obtain natural active compounds involve the pre-selection in a biological model and subsequently evaluation on specific models. The present study reports the evaluation of 35 extracts, fractions, and essential oils obtained from five species from the Annonaceae family on Artemia salina and Culex quinquefasciatus. The A. salina results were used as a pre-screening for larvicidal test about mosquitoes. A correlation of biological activity in both bioassays was observed for the hydroethanolic extracts and their respective hexane and chloroform fractions of the leaves of Annona species, except A. nutans. The same correlation was also observed for all tested essential oils and petroleum ether extracts from Duguetia species. It was possible to limit an interval of lethality about A. salina, which has a corresponding range to the larvicidal test against the mosquito. The main components present in D. lanceolata essential oil or enriched fraction were α-selinene, aristolochene, (E)-caryophyllene, and (E)-calamenene. For D. furfuracea, the main components present of the underground parts were (E)-asarone, 2,4,5-trimethoxystyrene, spathulenol, and bicyclogermacrene for aerial parts. The A. salina test could be used as a model for the pre-screening of larvicidal activity.
显示更多 [+] 显示较少 [-]Mercury dynamics in macroinvertebrates in relation to environmental factors in a highly impacted tropical estuary: Buenaventura Bay, Colombian Pacific 全文
2020
Gamboa-García, Diego Esteban | Duque, Guillermo | Cogua, Pilar | Marrugo-Negrete, José Luis
The environmental health of Buenaventura Bay, a highly impacted tropical estuary, is influenced by numerous human activities, including mining upstream. Large- and small-scale fishing plays an important role in the local economy, so we investigated the dynamic processes of bioaccumulation of mercury at basal trophic levels. Four samples were taken at each of the four locations in Buenaventura Bay during each of the four seasons of 2015. We measured the total mercury content (T-Hg, dry weight) in sediments and in muscle tissue across 17 macroinvertebrate species. The most abundant were the blue crab (C. arcuatus) and the mantis shrimp (S. aculeata aculeata). Blue crab showed an average muscle T-Hg value exceeding the limit of 0.2 g·g⁻¹, which is the maximum T-Hg level suggested for food consumption by vulnerable humans and populations: pregnant women, children, and the community that feeds from this source of protein on a daily basis. It was found that, 6.22% of individuals exceeded the 0.5 g·g⁻¹ level, which is the maximum T-Hg level suggested for food consumption by the general population: the population that consumes it sporadically. Significantly high values of T-Hg in blue crab and mantis shrimp occurred during low salinity conditions in the estuary, suggesting that Hg mainly originates from river runoff during the rainy season. Nevertheless, the biota-sediment accumulation factor (BSAF) was favored in high salinity, which could mean greater availability of Hg for higher levels of the estuarine food web in the dry season and in marine waters. In general, the T-Hg levels in some samples exceeded 0.2 g·g⁻¹. Therefore this pollutant must be monitored due to its biomagnification potential and as a threat to human health, especially that for the local population of fishermen and their families.
显示更多 [+] 显示较少 [-]A novel spherical fuzzy AHP-integrated spherical WASPAS methodology for petrol station location selection problem: a real case study for İstanbul 全文
2020
Ayyildiz, Ertugrul | Taskin Gumus, Alev
The petrol station location selection problem is taken into consideration in this study. In order to identify the main and sub-criteria for evaluation, the literature is reviewed and five experts from different companies are interviewed. After that, thirteen different alternative locations are for specified to evaluation. Then, the novel spherical fuzzy AHP-integrated spherical WASPAS methodology is structured in a fuzzy environment, and the petrol station location selection problem is evaluated with this methodology. In this study, a real application is presented for Istanbul to show the applicability of the proposed methodology. Subsequently, a sensitivity analysis is performed to explain and analyze the proposed methodology results. Finally, the results are presented and discussed with future directions.
显示更多 [+] 显示较少 [-]Degradation of BTEX mixture by a new Pseudomonas putida strain: role of the quorum sensing in the modulation of the upper BTEX oxidative pathway 全文
2020
Chicca, Ilaria | Becarelli, Simone | Dartiahl, Christopher | La China, Salvatore | De Kievit, Teresa | Petroni, Giulio | Di Gregorio, Simona | Levin, David B.
A new Pseudomonas putida strain (AQ8) was isolated from a decommissioned oil refinery’s soil in Italy and characterized for its ability to degrade BTEX. The draft genome of the new strain was sequenced and annotated for genes that encode enzymes putatively involved in BTEX degradation and quorum sensing. The strain was transformed with a plasmid expressing lactonase, which cleaves the autoinducer quorum sensing signal molecule, the acyl-homoserine lactone, to obtain a quorum sensing minus strain. P. putida AQ8 depleted the 40% on average of all the components of the initial BTEX concentration in 36 h. The quorum sensing minus strain, in the same time interval, depleted only the 10% of the initial BTEX concentration. The role of quorum sensing in regulating the expression of the annotated benzene/toluene dioxygenase gene (benzA) and biphenyl/toluene/benzene dioxygenase (bphA) genes, which are involved in BTEX degradation, was studied by quantitative RT-real-time quantitative (q)PCR analysis. The qPCR data showed decreased levels of expression of the benzA and bphA genes in the quorum sensing minus strain. Our results showed, for the first time, quorum sensing modulation of the level of transcription of dioxygenase genes in the upper BTEX oxidation pathway.
显示更多 [+] 显示较少 [-]An empirical analysis of the non-linear impacts of ICT-trade openness on renewable energy transition, energy efficiency, clean cooking fuel access and environmental sustainability in South Asia 全文
2020
Murshed, Muntasir
Energy security and environmental sustainability have become an integral policy agenda worldwide whereby the global economic growth policies are being restructured to ensure the reliability of energy supply and safeguard environmental well-being as well. However, technological inefficiency is one of the major hindrances in attaining these over-arching goals. Hence, this paper probed into the non-linear impacts of ICT trade on the prospects of undergoing renewable energy transition, improving energy use efficiencies, enhancing access to cleaner cooking fuels, and mitigating carbon dioxide emissions across selected South Asian economies: Bangladesh, India, Pakistan, Sri Lanka, Nepal, and Maldives. The results from the econometric analyses reveal that ICT trade directly increases renewable energy consumption, enhances renewable energy shares, reduces intensity of energy use, facilitates adoption of cleaner cooking fuels, and reduces carbon-dioxide emissions. Moreover, ICT trade also indirectly mitigates carbon-dioxide emissions through boosting renewable energy consumption levels, improving energy efficiencies, and enhancing cleaner cooking fuel access. Hence, these results, in a nutshell, portray the significance of reducing the barriers to ICT trade with respect to ensuring energy security and environmental sustainability across South Asia. Therefore, it is ideal for the government to gradually lessen the trade barriers to boost the volumes of cross-border flows of green ICT commodities. Besides, it is also recommended to attract foreign direct investments for the potential development of the respective ICT sectors of the South Asian economies.
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