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Correction to: Monte Carlo fingerprinting of the terrestrial sources of different particle size fractions of coastal sediment deposits using geochemical tracers: some lessons for the user community Полный текст
2019
Gholami, Hamid | Jafari Takhti Najad, Ebrahim | Collins, Adrian L. | Fathabadi, Aboalhasan
The original publication of this paper contains a mistake. The correct University name of the 3rd affiliation is shown in this paper.
Показать больше [+] Меньше [-]A two decades study on ozone variability and trend over the main urban areas of the São Paulo state, Brazil Полный текст
2019
Schuch, Daniel | de Freitas, Edmilson Dias | Espinosa, Sergio Ibarra | Martins, Leila Droprinchinski | Carvalho, Vanessa Silveira Barreto | Ramin, Bruna Ferreira | Silva, Jayne Sousa | Martins, Jorge Alberto | de Fatima Andrade, Maria
In this paper, we analyze the variability of the ozone concentration over São Paulo Macrometropolis, as well the factors, which determined the tendency observed in the last two decades. Time series of hourly ozone concentrations measured at 16 automated stations from an air quality network from 1996 to 2017 were analyzed. The temporal variability of ozone concentrations exhibits well-defined daily and seasonal patterns. Ozone presents a significant positive correlation between the number of cases (thresholds of 100–160 μg m⁻³) and the fuel sales of gasohol and diesel. The ozone concentrations do not exhibit significant long-term trends, but some sites present positive trends that occurs in sites in the proximity of busy roads and negative trends that occurs in sites located in residential areas or next to trees. The effect of atmospheric process of transport and ozone formation was analyzed using a quantile regression model (QRM). This statistical model can deal with the nonlinearities that appear in the relationship of ozone and other variables and is applicable to time series with non-normal distribution. The resulting model explains 0.76% of the ozone concentration variability (with global coefficient of determination R¹ = 0.76) providing a better representation than an ordinary least square regression model (with coefficient of determination R² = 0.52); the effect of radiation and temperature are the most critical in determining the highest ozone quantiles.
Показать больше [+] Меньше [-]A study of the predictive factors of mortality in acute poisoning with aluminum phosphide with special reference to echocardiography and SOFA score Полный текст
2019
Sheta, Abeer A. | El-Banna, Asmaa S. | Elmeguid, Rania Abd | Mohamed, Hany E. | Gad, Nehad H.
Aluminum phosphide (AlP) is considered now one of the most common causes of poisoning among agricultural pesticides. Poisoning with AlP is extremely toxic to humans with high mortality rate. The aim of this work was to evaluate the prognostic factors and outcome of acute aluminum phosphide poisoning in Alexandria Main University Hospital during a period of 6 months from 1 November 2017 until the end of April 2018, highlighting the role of SOFA score and echocardiography in predicting the mortality. The prospective study was conducted on all patients admitted with acute AlP poisoning to Alexandria Main University Hospital for those 6 months. Patients’ data were collected in a special sheet and included biosocial data, medical history, poisoning history, complete medical examination, investigations, duration of hospital stay, and the outcome. All patients were assessed according to SOFA score on admission. Thirty patients were admitted during the period of the current study. Females outnumbered males in all age groups with a sex ratio of 2.75:1. The mean age of patients was 22.77 ± 12.79 years. 96.6% of patients came from rural areas. 93.3% of the cases were exposed to poisoning at home, where suicidal poisoning accounted for (86.7%) of cases. 43.3% of patients died (n = 13), and the median value of SOFA score among non-survivors was 10, versus 1 among survivors. The median value of ejection fraction among non-survivors (25%) was half its value in survivors (50%). Although there were many predictors of severity of AlP poisoning, SOFA score was the most predictive factor of mortality detected by multivariate analysis.
Показать больше [+] Меньше [-]Investigating the urbanization process and its impact on vegetation change and urban heat island in Wuhan, China Полный текст
2019
Gui, Xuan | Wang, Lunche | Yao, Rui | Yu, Deqing | Li, Chang’an
Rapid urbanization significantly changes vegetation coverage and heat distribution, which threatens the sustainable development and the quality of life. As the largest developing city in Central China, Wuhan was chosen as the experimental region. This study investigated the urbanization process of Wuhan from 1989 to 2917 based on Landsat data. Combined with MODIS EVI (Enhanced Vegetation Index) and LST (Land Surface Temperature) data, vegetation disturbance and surface urban heat island (SUHI) caused by urbanization were discussed for 2001–2017. Furthermore, correlation between ∆EVI (urban EVI minus rural EVI) and ∆LST (urban LST minus rural LST) was also conducted. The results were as follows: (1) Wuhan experienced a strong urbanization over the past 29 years, with an increasing urban expansion rate and the altered dominant urban expansion pattern (edge expansion and infilling). After the enhanced vegetation functions and urban increased structures, the urbanization finally caused the fragmented patches and irregular urban shapes. (2) Urbanization had a positive effect on LST but a negative effect on EVI. From 2001 to 2017, the highest increasing rate of ∆LST for the old urban area (OUA) and urbanized area (UA) was both observed in summer daytime (OUA, 0.106 °C/a; UA, 0.207 °C/a). The decreasing rate of ∆EVI reached the highest value in summer (OUA, 0.00697/a; UA, 0.00298/a). (3) There was a strong negative correlation (except spring and winter for OUA) between ∆EVI and ∆LST in daytime, which proved that the activity of vegetation in daytime could relieve LST to a certain extent. This study clarifies the dynamic urbanization process of Wuhan and discusses its impacts on vegetation change and SUHI. Efficiently investigating urbanization process and quantifying its impacts on urban environment are critical for regional ecological conservation.
Показать больше [+] Меньше [-]Microalgal biomass production through phycoremediation of fresh market wastewater and potential applications as aquaculture feeds Полный текст
2019
Apandi, Najeeha Mohd | Radin Mohamed, Radin Maya Saphira | Al-Gheethi, Adel | Mohd Kassim, Amir Hashim
Microalgal biomass produced from the phycoremediation of wastewater represents an important protein source, lipids, and natural antioxidants and bioproducts. Therefore, the microalgal biomass and their derived compounds are used in animal and aquaculture feed as well as human nutrition and health products. Many microalgal species have shown promising potential for many bioproducts. However, significant processes to find the optimum quality and quantity of microalgal biomass are still required especially when it is used as a replacement for aquaculture feed. The limitations lie in the selection of microalgal species and their production. The present review discusses the potential generation of bioproducts from microalgal biomass resulting from the phycoremediation of wet market wastewater. The consortium approach in wastewater treatment and the comparison between biomass production and available common feeds for aquaculture were reviewed.
Показать больше [+] Меньше [-]Understanding the effect of indoor air pollution on pneumonia in children under 5 in low- and middle-income countries: a systematic review of evidence Полный текст
2019
Adaji, Enemona Emmanuel | Ekezie, Winifred | Clifford, Michael | Phalkey, Revati
Exposure to indoor air pollution increases the risk of pneumonia in children, accounting for about a million deaths globally. This study investigates the individual effect of solid fuel, carbon monoxide (CO), black carbon (BC) and particulate matter (PM)₂.₅ on pneumonia in children under 5 in low- and middle-income countries. A systematic review was conducted to identify peer-reviewed and grey full-text documents without restrictions to study design, language or year of publication using nine databases (Embase, PubMed, EBSCO/CINAHL, Scopus, Web of Knowledge, WHO Library Database (WHOLIS), Integrated Regional Information Networks (IRIN), the World Meteorological Organization (WMO)-WHO and Intergovernmental Panel on Climate Change (IPCC). Exposure to solid fuel use showed a significant association to childhood pneumonia. Exposure to CO showed no association to childhood pneumonia. PM₂.₅ did not show any association when physically measured, whilst eight studies that used solid fuel as a proxy for PM₂.₅ all reported significant associations. This review highlights the need to standardise measurement of exposure and outcome variables when investigating the effect of air pollution on pneumonia in children under 5. Future studies should account for BC, PM₁ and the interaction between indoor and outdoor pollution and its cumulative impact on childhood pneumonia.
Показать больше [+] Меньше [-]Physiological damages of Sargassum cymosum and Hypnea pseudomusciformis exposed to trace metals from mining tailing Полный текст
2019
Costa, Giulia Burle | Ramlov, Fernanda | de Ramos, Bruna | Koerich, Gabrielle | Gouvea, Lidiane | Costa, Patrícia Gomes | Bianchini, Adalto | Maraschin, Marcelo | Horta, Paulo A. Jr
The damages of Mariana’s mining mud in the physiology of the brown algae Sargassum cymosum and its main epiphytic, the red algae Hypnea pseudomusciformis, were evaluated by controlled essays. Seaweeds were exposed to presence or absence of mud, isolated or in biological association, for 5 and 15 days. Measured parameters were growth rates, biochemical descriptors, and the chemical investigation of concentration and metal profile of the mud dissolved in seawater. Results showed that the highest values for metals were Al > Fe > Mn > Zn in both exposure periods. The mud also affected the growth rate with lethality in both isolated and associative treatments with H. pseudomusciformis after 15 days. According to our redundancy analysis (RDA), the profile and concentration of all metallic elements can induce different physiological responses of the organisms. We were able to observe a higher physiological adaptive ability of S. cymosum against the long-term presence of metals by the synthesis of phenolic compounds, while the deviation of metabolic routes in H. pseudomusciformis can be addressed as the main responsible for its lethality. Moreover, the presence of Hypnea in associative treatments reduces Sargassum’s detoxification ability. The present results reinforce the importance of biological interaction studies in a context of physiological resilience against mining mud pollution and mutual influences of species over the individual ability to avoid oxidative stress.
Показать больше [+] Меньше [-]Low-carbon electricity generation–based dynamic equilibrium strategy for carbon dioxide emissions reduction in the coal-fired power enterprise Полный текст
2019
Xu, Jiuping | Feng, Qing | Lv, Chengwei | Huang, Qian
Climate change is already resulting in extreme devastation in the earth, with carbon dioxide emissions produced by coal-fired power plants being the largest contributor. Therefore, integrated coal purchasing, blending, and distribution strategies are playing a more important role in large-scale coal-fired power enterprises due to the need to reduce carbon dioxide emissions and operational costs. In this study, a dynamic equilibrium strategy for integrated coal purchasing, blending, and distribution under an uncertain environment is proposed to reduce carbon dioxide emissions in large-scale coal-fired powered enterprises; the practicality and efficiency of which are verified using a real-world case. Sensitivity analyses under different carbon dioxide emissions levels and satisfactory degrees were also conducted to give insights into the conflict between economic development and environmental protection for large-scale coal-fired power enterprises, and balance short-term and long-term production plans. The results indicated that the proposed method was able to achieve economic-environmental coordination and sustainable development. Compared to previous studies, the developed model was found to be able to reduce carbon emissions by about 30% compared with the maximum carbon emissions and improve carbon emissions reduction performance to assist in mitigating climate change.
Показать больше [+] Меньше [-]Putative impacts of phytogenic additives to ameliorate lead toxicity in animal feed Полный текст
2019
Abd El-Hack, Mohamed E. | Abdelnour, Sameh A. | Abd El-Moneim, Abd El-Moneim E. | Arif, Muhammad | Khafaga, Asmaa | Shaheen, Hazem | Samak, Dalia | Swelum, Ayman A.
Lead (Pb) is a toxic heavy metal and an environmental pollutant, particularly because of its anthropogenic activity. The main impacts of Pb is recognized to cause injurious influences of various levels of the tropic chain, due to bio-accumulated lead causes many health issues such as intoxication of different body organs, such as kidneys and liver, and reproductive and nervous systems. Industrial lead toxicity has reduced as a result of the attempts to decrease the lead levels in the surrounding work environment. Conversably, health risks related with long-term environmental exposure to a low dose of Pb have been steadily demonstrated. Long-term exposure to lead toxicity caused inflammatory infiltration, degenerative changes in testicular tissues, reduction in spermatocytes, necrosis of hepatocytes, degeneration in renal tubules, and renal epithelium hypertrophy. Hence, we need an influential approach to vanquish lead toxicity. This consequence has emerged the necessity for potentially safe represent remedy, favorably keeping both enhancement and chelating of the antioxidant competences. Many antioxidants have been used for chelating heavy toxic pollutants such as lead and oxidative stress released in excess during lead exposure. Several studies have stated the noticeable gathering of herbal singly or in combination in modulating lead-induced disturbances, therefore proposing great promise in enhancing health status and welfare of man as well as animals. For this, in the current review, we tried to discuss the enormous harmful influences of lead toxicity on the animal model and the disturbing truth that this detrimental toxic substance can be found quite simply in the surroundings and amplitude.
Показать больше [+] Меньше [-]Experimental study on radon exhalation behavior of heap leaching uranium ore column with dilute sulfuric acid Полный текст
2019
In order to study the radon release behavior when heap leaching uranium ores with dilute sulfuric acid, unleached uranium ores from a uranium mine in southern China were selected as test samples. Adopting parameters from leaching processes commonly used in uranium mines, a laboratory experiment was carried out for 21 days with a one-dimensional acid heap leaching experimental column. The surface radon exhalation rate of uranium ore column was determined by static accumulation method while spraying with deionized water and dilute sulfuric acid. The uranium leaching rate and ore column height for all 21 days of the experiment were also measured. The results show that (1) when sprayed with a leaching agent, the surface radon exhalation rate of uranium ore column initially increased with time sharply. After a maximum value was reached, the rate gradually decreased and stabilized. When the spraying stopped, the surface radon exhalation rate of uranium ore column initially decreased, before increasing until it tended to stabilize. (2) During the entirety of the 21-day leaching experiment, the cumulative leaching rate of uranium increased gradually with time. On the other hand, the surface radon exhalation rate of uranium ore column fluctuated, but the leaching of uranium from uranium ores had almost no effect on the radon exhalation rate. (3) There was no linear correlation between the surface radon exhalation rate and the residual height of ore column during leaching, but the collapsing event of ore column was the direct inducing factor of the fluctuation of surface radon exhalation rate.
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