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Trilemma assessment of energy intensity, efficiency, and environmental index: evidence from BRICS countries Texte intégral
2020
Baloch, Zulifqar Ali | Tan, Qingmei | Iqbal, Nadeem | Mohsin, Muhammad | Abbas, Qaiser | Iqbal, Wasim | Chaudhry, Imran Sharif
This paper provides an assessment of energy density and energy efficiency and creates an important indicator of environmental performance. This article applied two mathematical models and econometric techniques to obtain detailed and specific results. The DEA and the non-normative account aggregation mean a collective aggregation to form a mathematical aggregation tool to create an environmental index for the BRICS countries (Brazil, Russia, India, China, and South Africa) based on available data from 2011 to 2016. The advantage of the proposed approach is to manage the irregularities of the data and follow the desired properties of the index number. The current paper is relevant for the broad scope of construction, the environmental index, and the evolution of the rankings of countries based on multiple indicators. Our results indicate that Brazil and Russia have the highest values of the Environmental Performance Index, which range between 67.44 and 60.70, respectively. India has a minimum value of 30.57 of the environmental index. The analysis shows that Brazil, Russia, and South Africa have the best scores and that these countries have the best results, while China and India also have the best results. This study can help form a valuable political tool for the development and development of the country’s politics.
Afficher plus [+] Moins [-]Ambient air pollution and its influence on human health and welfare: an overview Texte intégral
2020
Almetwally, Alsaid Ahmed | Bin-Jumah, May | Allam, Ahmed A.
Human health is closely related to his environment. The influence of exposure to air pollutants on human health and well-being has been an interesting subject and gained much volume of research over the last 50 years. In general, polluted air is considered one of the major factors leading to many diseases such as cardiovascular and respiratory disease and lung cancer for the people. Besides, air pollution adversely affects the animals and deteriorates the plant environment. The overarching objective of this review is to explore the previous researches regarding the causes and sources of air pollution, how to control it and its detrimental effects on human health. The definition of air pollution and its sources were introduced extensively. Major air pollutants and their noxious effects were detailed. Detrimental impacts of air pollution on human health and well-being were also presented.
Afficher plus [+] Moins [-]Nanocurcumin improved glucose metabolism in streptozotocin-induced diabetic rats: a comparison study with Gliclazide Texte intégral
2020
Afifi, Mohamed | Alkaladi, Ali | Abomughaid, Mosleh M. | Abdelazim, Aaser M.
In the present study, the biochemical effect of nanocurcumin (nanoCUR) compared with Gliclazide (GLZ) on the diabetic rats was studied. Forty male albino rats (Sprague Dawley) weighted 110 ± 20 g were used. Rats were randomly separated into two groups. Control, received no treatment. Streptozotocin (STZ)-induced diabetic groups take 5 ml/kg of STZ in normal saline daily for 30 days, further divided into diabetic non-treated group, did not receive any treatment: diabetic group treated by nanoCUR, received 15 mg/kg/day of nanoCUR orally for 30 days; diabetic group treated by GLZ, received 2 mg/kg/day of GLZ for 30 days. The mean body weights of all rats were registered and serum samples were collected for determination of fasting blood glucose (FBG), insulin concentration, liver glucokinase (GK), and glycogen synthase (GS) activities. Liver tissues were collected for determination of mRNA expression of insulin (INS), insulin receptor A (IRA), glucokinase (GK), and glucose transporter 2 (GLUT2). The results revealed a significant reduction of body weight in diabetic rats, with no significant differences in nanoCUR and GLZ groups. There was a decline in FBG levels and significant elevation of INS levels, GK, and GS activities in diabetic rats received nanoCUR and GLZ. mRNA expression of INS, IRA, GK, and GLUT2 significantly upregulated in diabetic rats received nanoCUR and GLZ. The amazing observation was a non-significant difference in all measured parameters between nanoCUR and GLZ groups. In conclusion, nanoCUR is able to improve cellular uptake of glucose, the hepatic insulin signaling, and insulin sensitivity in diabetic rats. Its effect was similar to standard hypoglycemic drug (GLZ).
Afficher plus [+] Moins [-]Oxidative state of the frugivorous bat Sturnira lilium (Chiroptera: Phyllostomidae) in agricultural and urban areas of southern Brazil Texte intégral
2020
Oliveira, Fernanda Weinmann | Schindler, Monica Santin Zanatta | Corá, Denyelle Hennayra | Thiel, Nathana | Siebel, Anna Maria | Galiano, Daniel
Exposure to contaminants is one of the main threats to all living organisms. In this context, bats have been used to indicate environmental contaminants in urban and agricultural environments, since they are extremely sensitive to changes in the ecosystem and easily accumulate waste in their body tissues. Among bats, Sturnira lilium, is a frugivorous species widely distributed and abundant in Brazil that uses an extensive variety of habitats and shelters. In this study, we aimed to evaluate the oxidative state of S. lilium individuals in agricultural and urban areas in southern Brazil. Individuals were sampled in agricultural and urban areas from November 2017 to March 2018 through the mist-net method. Parameters of the superoxide dismutase (SOD) and catalase (CAT) enzyme activity, non-protein thiols (NPSH), and lipid peroxidation (TBARS) were determined based on liver tissue. A total of 46 individuals were captured, 29 of them in urban areas and 17 in agricultural areas. We found that S. lilium individuals from agricultural areas showed a significant increase in TBARS, NPSH, and SOD activity, compared to individuals from urban areas. The activity of the antioxidant enzyme CAT did not differ. The present findings suggest that the species S. lilium, which are widely distributed and abundant in Brazil in urban and agricultural areas, can usefully be employed in biomonitoring programs. Further studies are to be encouraged to refine our knowledge on the potential DNA damage caused by environmental contamination, as well as identify potential contaminants to bats.
Afficher plus [+] Moins [-]Evaluation of two contrasted activated carbon-based sequestration strategies to reduce soil-bound chlordecone bioavailability in piglets Texte intégral
2020
Delannoy, Matthieu | Techer, Didier | Yehya, Sarah | Razafitianamaharavo, Angelina | Amutova, Farida | Fournier, Agnès | Baroudi, Moumen | Montarges-Pelletier, Emmanuelle | Rychen, Guido | Feidt, Cyril
Chlordecone (Kepone) (CLD) is a highly persistent pesticide formerly used in the French West Indies. High levels of this pesticide are still found in soils and represent a subsequent source of contamination for outdoor-reared animals which may ingest involuntary non negligible amounts of soil. In that context, sequestering matrices like activated carbons (ACs) may be used to efficiently decrease the bioavailability of such organic pollutants. The present study intends to assess the respective efficiency of two sequestering strategies where two different ACs were provided either via feed incorporation or via soil amendment. This study involved 20 piglets randomly distributed into 5 experimental groups (4 replicates). All groups were exposed to 10 μg of CLD per kg of BW per day during 10 days via a contaminated soil. In both “Soil-ACs” treatment groups, the contaminated soil was amended by 2% (mass basis) of one of the two ACs. The two “Feed-ACs” groups received the contaminated soil and one dough ball containing 0.5% (mass basis) of one of the ACs. The piglets were then euthanized before collection of pericaudal adipose tissue and the whole liver and CLD analysis. A significant decrease of CLD concentrations in liver and adipose tissue was observed only in the “Soil-ACs” groups in comparison with the control group (P < 0.001). This decrease was particularly important for the coconut shell activated carbon where relative bioavailability was found lower than 1.8% for both tissues.
Afficher plus [+] Moins [-]Preserving wheat grain quality and preventing aflatoxin accumulation during storage without pesticides using dry chain technology Texte intégral
2020
Bakhtavar, Muhammad Amir | Afzal, Irfan
Storage of wheat in conventional packaging materials is not safe as seeds gain moisture from surrounding air of high relative humidity which promotes growth of fungal and insect pests and loss of quality during storage. Implementing the dry chain, initial drying to low moisture content followed by storage in hermetic bags to maintain low moisture may prevent these losses without using fumigants or chemicals. Different levels of initial moisture contents (SMC), i.e., 8, 10, 12, and 14% and packaging materials, including hermetic super bags along with paper, woven polypropylene (PP), jute, and cloth bags were used as two factors for this experiment. After 4 months of storage, small variation in SMC of seed was observed in super bags while SMC increased significantly in conventional packaging materials. Higher storage losses (≈9%), grain quality losses and aflatoxin B₁, B₂, G₁, and G₂ contamination (1–2 ppb) in conventional packaging materials were linked to high seed moisture contents. Storage in hermetic bags at 8 and 10% SMC ideally preserved seed quality. In conclusion, hermetic storage of wheat at low seed moisture maintains a dry chain and prevents aflatoxin contamination and grain quality losses and offers an organic approach to avoid contamination of food grains.
Afficher plus [+] Moins [-]Coordinated development of economic growth and ecological efficiency in Jiangsu, China Texte intégral
2020
Wang, Shijin | Hua, Guihong | Yang, Lizhu
In order to realize sustainable development, ecological efficiency is particularly important and deserving of further study and discussion in China. Thus, the study proposed a comprehensive index for ecological efficiency in Jiangsu and evaluated the ecological efficiency of 13 cities in the year of 2007, 2012, and 2017 by using entropy-weighting TOPSIS method. Based on coupling model, the study discussed the interaction between economic growth and ecological efficiency in Jiangsu. The results indicated that the ecological efficiency of Jiangsu in these three years differed considerably. Ecological efficiency is the highest in central Jiangsu, whereas ecological efficiency in the northern and southern parts of Jiangsu is relatively low from the perspective of horizontal space. In terms of coupling, Wuxi and Suzhou were the stablest in southern Jiangsu. Economic growth in the central Jiangsu fluctuated, Suqian lagged. Furthermore, based on the findings, the industrial structure should be adjusted to improve ecological efficiency. In addition, the use of innovation and rational foreign direct investment and other measures should be promoted. These proposals aim at improving ecological efficiency and achieving overall sustainable development in Jiangsu, China.
Afficher plus [+] Moins [-]Spatiotemporal variation and determinants of population’s PM2.5 exposure risk in China, 1998–2017: a case study of the Beijing-Tianjin-Hebei region Texte intégral
2020
Jin, Ning | Li, Junming | Jin, Meijun | Zhang, Xiaoyan
PM₂.₅ pollution has emerged as a global human health risk. The best measure of its impact is a population’s PM₂.₅ exposure (PPM₂.₅E), an index that simultaneously considers PM₂.₅ concentrations and population spatial density. The spatiotemporal variation of PPM₂.₅E over the Beijing-Tianjin-Hebei (BTH) region, which is the national capital region of China, was investigated using a Bayesian space-time model, and the influence patterns of the anthropic and geographical factors were identified using the GeoDetector model and Pearson correlation analysis. The spatial pattern of PPM₂.₅E maintained a stable structure over the BTH region’s distinct terrain, which has been described as “high in the northwest, low in the southeast”. The spatial difference of PPM₂.₅E intensified annually. An overall increase of 6.192 (95% CI 6.186, 6.203) ×10³ μg/m³ ∙ persons/km² per year occurred over the BTH region from 1998 to 2017. The evolution of PPM₂.₅E in the region can be described as “high value, high increase” and “low value, low increase”, since human activities related to gross domestic product (GDP) and energy consumption (EC) were the main factors in its occurrence. GDP had the strongest explanatory power of 76% (P < 0.01), followed by EC and elevation (EL), which accounted for 61% (P < 0.01) and 40% (P < 0.01), respectively. There were four factors, proportion of secondary industry (PSI), normalized differential vegetation index (NDVI), relief amplitude (RA), and EL, associated negatively with PPM₂.₅E and four factors, GDP, EC, annual precipitation (AP), and annual average temperature (AAT), associated positively with PPM₂.₅E. Remarkably, the interaction of GDP and NDVI, which was 90%, had the greatest explanatory power for PPM₂.₅E ′ s diffusion and impact on the BTH region.
Afficher plus [+] Moins [-]Exploring the effect of subjective air pollution on happiness in China Texte intégral
2020
Song, Yan | Zhou, Aina | Zhang, Ming
Previous papers that study the relationship between air pollution and happiness have not paid much attention to subjective air pollution. This paper attempts to explore the influence of subjective air pollution on happiness, the heterogeneity of the effects, and people’s subjective willingness for improving air quality. We match the data of Chinese General Social Survey with local air quality and mainly based on the method of regression discontinuity. Our study shows that the public’s subjective air pollution perception has significant negative effects on their happiness. The negative effects on happiness of unhealthy people and middle-aged/old people are greater than that of healthy people and young people. Moreover, residents who are relatively vulnerable to the harm of air pollution appear to be more willing to pay for the improvement of air quality. These results indicate that in order to improve air quality more rationally and effectively, not only should the government concentrate on the improvement of objective air quality but also pay attention to the public’s subjective feelings, as well as taking the subjective needs of local residents into consideration in the process of air pollution control.
Afficher plus [+] Moins [-]Characterization of particulate matter emissions in urban train braking - An investigation of braking conditions influence on a reduced-scale device Texte intégral
2020
Octau, Charlene | Meresse, Damien | Watremez, Michel | Schiffler, Jesse | Lippert, Marc | Keirsbulck, Laurent | Dubar, Laurent
The particulate matter emissions related to the braking of railway rolling stock are investigated using a reduced scale braking device. Samples of organic materials and cast iron discs are tested for different nominal contact pressures and disc surface temperatures, representative of real conditions. The aim of this work is to investigate the influence of braking conditions on the global amount of particles emitted, their distribution in number and size, and their morphological and chemical characteristics. To be representative, the tested conditions are designed to dissipate the same amount of energy for all the braking events by adjusting the pad application duration. The results show that for the same dissipated energy, a temperature increase above a transition value in the range of 230–280 ∘C depending on the braking conditions modifies the size and number distributions of the generated particles. The results obtained are of interest to better represent their propagation through CFD modelling according to the characteristic of the particle emission.
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