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Resultados 2731-2740 de 4,896
A study of the predictive factors of mortality in acute poisoning with aluminum phosphide with special reference to echocardiography and SOFA score
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.
Mostrar más [+] Menos [-]Evaluating renewable energy sources for implementing the hydrogen economy in Pakistan: a two-stage fuzzy MCDM approach
2019
Xu, Li | Shah, Syed Ahsan Ali | Zameer, Hashim | Solangi, Yasir Ahmed
Hydrogen can play a crucial role in increasing energy security and reducing greenhouse gases in Pakistan. Hydrogen can only be a clean and sustainable fuel if it is generated from renewable energy sources (RES). Thus, it is important to evaluate viability of RES for hydrogen production. This study developed a two-stage fuzzy MCDM (Multi-criteria decision-making) approach to select the most efficient RES. In the first stage, fuzzy analytical hierarchy process (AHP) obtained the relative weights of four criteria for the selection of best RES. These criteria included commercial potential, environmental impacts, economic benefits, and social acceptance. In the second stage, data envelopment analysis (DEA) measured the relative efficiency of RES using weights of criteria as outputs, and the cost of RES-based electricity generation as input. The results indicated that wind and solar are the most efficient sources of hydrogen production in Pakistan. Municipal solid waste (MSW) and biomass can also be considered a feedstock for the hydrogen economy. Geothermal reported to be the less efficient source and thus is not recommended at present. Sensitivity analysis confirmed the robustness of results obtained using the developed framework.
Mostrar más [+] Menos [-]Migration and transformation of different phosphorus forms in rainfall runoff in bioretention system
2019
Song, Yujia | Song, Shoufa
Artificial bioretention system consisting of Ophiopogon japonicus infiltration medium was used to simulate an infiltration experiment of rainfall runoff. Continuous extraction method was used to detect contents of inorganic phosphorus (P) under exchangeable state (Ex-P) and aluminium phosphate (Al–P) and iron phosphate (Fe–P) at different depths (0, 5, 15 and 35 cm) of soil infiltration medium in bioretention system. Effluent total P (TP) concentration of the system was also monitored. Results indicated that the adsorption of inorganic P, Al–P and Fe–P by soil infiltration medium was implemented layer by layer from top to bottom and gradually weakened. Moreover, Ex-P was gradually transformed into Al–P and Fe–P, whereas Al–P was gradually transformed into Fe–P; thus, Ex-P content reduced layer by layer, whereas Al–P and Fe–P gradually accumulated. The TP removal rate in runoff rainwater by the system was more than 90%, where the TP that was not used by plants was under dynamic equilibrium in water–soil–root system/biological system.
Mostrar más [+] Menos [-]Metabolism of obeticholic acid in brown bullhead (Ameiurus nebulosus)
2019
Mach, Samuel | Jegorov, Alexandr | Šimek, Zdeněk
Analysis of brown bullhead (Ameiurus nebulosus) bile by ultra performance liquid chromatography high-resolution mass spectrometry (UPLC/HRMS) revealed a series of bile acids similar to those found in humans. Accordingly, we chose this fish as a model organism to examine the metabolism of obeticholic acid, a bile acid used to treat a number of human liver diseases and the one that has the potential to occur as an environmental contaminant. The taurine and glycine conjugates of obeticholic acid and keto-obeticholic acid were identified, as well as the D-cysteinolic acid conjugate of obeticholic acid, likely a metabolite specific to fish. In addition, metabolites of obeticholic acid (sulphate and glucuronide) and several hydroxy-obeticholic acid derivatives were found, representing typical pathways of primary and secondary steroid metabolism. Brown bullhead exposed to obeticholic acid at a dose of 100 mg/kg gave no overt signs of distress or toxicity.
Mostrar más [+] Menos [-]Characteristic and mechanism of sorption and desorption of benzene on humic acid
2019
Tang, Zhi | Li, Yilian | Yang, Zhe | Liu, Danqing | Tang, Min | Yang, Sen | Tang, Ye
The sorption/desorption behaviors of benzene, toluene, ethylbenzene, and xylene (BTEX) on soil organic matter (SOM) have a significant influence on their fate and bioavailability in soil. Humic acid (HA) is a major fraction of SOM. And due to its various structural properties and chemical composition, the sorption/desorption characteristics and mechanisms of HA are diverse for organic contaminants. In this study, batch experiments were conducted to investigate the sorption/desorption behavior of benzene on HA at different conditions (temperature, pH, and ionic strength). The particle size of HA increased at lower initial pH which promoted sorption capacity for benzene, illustrating that HA with larger particle size may develop preferential chemical conformation for benzene sorption at lower pH. Sorption isotherms indicated that the sorption of benzene on HA is an exothermic and spontaneous physical process. And kinetic studies showed that the sorption of benzene on HA is controlled by the diffusion process and the availability of sorption sites. Meanwhile, weak sorbent-sorbate interaction is presented in the desorption experiment. There was no obvious effect of ionic strength on benzene sorption, suggesting that the sorption process is not controlled by ion-exchange or electrostatic interaction. Combined with FTIR analysis, the hydrophobic partitioning and π-π conjugative interaction are the possible sorption mechanisms of benzene on HA.
Mostrar más [+] Menos [-]Testing the impact of real interest rate, income, and energy consumption on Turkey’s CO2 emissions
2019
Isiksal, Aliya Zhakanova | Samour, Ahmed | Resatoglu, Nil Gunsel
This paper aims to explore the impact of real interest rates (RIN), income, trade, foreign direct investment (FDI), and energy consumption on Turkey’s carbon dioxide emissions (CO₂) over the period from 1980 to 2014. This study differs from the existing literature by introducing a new discussion in the determination of environmental degradation, namely real interest rate. Hatemi-J (HJ) cointegration with two structural breaks and the newly developed Bayer–Hanck (BH) combined cointegration tests are used to enhance and support the robustness of the autoregressive distributed lag (ARDL) bounds test. The Granger causality test within the vector error correction model (VECM) is employed to examine the causality direction among the variables in both the short and long run. The empirical results demonstrate that RIN negatively effects CO₂ emissions. This impact is also supported through energy, income, and FDI channels. It is suggested that policy makers should promote the stability of the real interest rates channel to reduce CO₂ emissions and encourage the renewable energy investment through the production of electricity using renewable sources.
Mostrar más [+] Menos [-]Development of hybrid processes for the removal of volatile organic compounds, plasticizer, and pharmaceutically active compound using sewage sludge, waste scrap tires, and wood chips as sorbents and microbial immobilization matrices
2019
de Toledo, Renata Alves | Hin Chao, U. | Shen, Tingting | Lu, Qihong | Li, Xueqing | Shim, Hojae
This study evaluated the reutilization of waste materials (scrap tires, sewage sludge, and wood chips) to remove volatile organic compounds (VOCs) benzene/toluene/ethylbenzene/xylenes/trichloroethylene/cis-1,2-dichloroethylene (BTEX/TCE/cis-DCE), plasticizer di(2-ethylhexyl) phthalate (DEHP), and pharmaceutically active compound carbamazepine from artificially contaminated water. Different hybrid removal processes were developed: (1) 300 mg/L BTEX + 20 mg/L TCE + 10 mg/L cis-DCE + tires + Pseudomonas sp.; (2) 250 mg/L toluene + sewage sludge biochar + Pseudomonas sp.; (3) 100 mg/L DEHP + tires + Acinetobacter sp.; and (4) 20 mg/L carbamazepine + wood chips + Phanerochaete chrysosporium. For the hybrid process (1), the removal of xylenes, TCE, and cis-DCE was enhanced, resulted from the contribution of both physical adsorption and biological immobilization removal. The hybrid process (2) was also superior for the removal of DEHP and required a shorter time (2 days) for the bioremoval. For the process (3), the biochar promoted the microbial immobilization on its surface and substantially enhanced/speed up the bioremoval of toluene. The fungal immobilization on wood chips in the hybrid process (4) also improved the carbamazepine removal considerably (removal efficiencies of 61.3 ± 0.6%) compared to the suspended system without wood chips (removal efficiencies of 34.4 ± 1.8%). These hybrid processes would not only be promising for the bioremediation of environmentally concerned contaminants but also reutilize waste materials as sorbents without any further treatment.
Mostrar más [+] Menos [-]Application of different single extraction procedures for assessing the bioavailability of heavy metal(loid)s in soils from overlapped areas of farmland and coal resources
2019
Luo, Ping | Xiao Xin, | Han, Xiaoxuan | Ma, You | Sun, Xiaofei | Jiang, Jiachao | Wang, Hui
Heavy metal(loid) extraction from soils in overlapped areas of farmland and coal resources (OAFCR) is crucial in understanding heavy metal bioavailability in soil and the subsequent risks to crops and consumers. However, limited attention has been paid to the extraction procedure of heavy metal(loid)s in OAFCR soils in the research. This study therefore explored different single and mixed extraction procedures, such as acetic acid (HOAc), citric acid, ammonium bicarbonate-diethylenetriaminepentaacetic acid (AB-DTPA), ethylene diamine tetraacetic acid + ammonium acetate (EDTA+NH₄OAc), and total digestion (HNO₃-HClO₄-HF) to determine the bioavailability of As, Cd, Cr, Cu, Pb, and Zn in OAFCR soil in Xuzhou, China. The results showed the metal(loid) extraction capacity from soil of the different procedures could be ranked as AB-DTPA > EDTA+NH₄OAc > HOAC > citric acid. The transfer ability of heavy metal(loid)s from soil to wheat tissues and from wheat roots to aerial parts was analyzed by calculating the bioconcentration factor and transfer factor, respectively. Transfer factors of all metal(loid)s were < 1 except Cr whose transfer factor from root to shell and straw were > 1. It is suspected that foliar uptake plays a dominant role in Cr uptake. Correlation analysis between the bioavailability of heavy metal(loid)s in soil and uptake in respective wheat tissues was performed to recommend the best extraction procedures for different studies. The results show that AB-DTPA extraction is recommended for Cu uptake to wheat roots, straws, shells and grains, Zn uptake to roots, and Cd uptake to roots and straws.
Mostrar más [+] Menos [-]Larvicidal and pupicidal activities of eco-friendly phenolic lipid products from Anacardium occidentale nutshell against arbovirus vectors
2019
de Carvalho, George Harrison Ferreira | de Andrade, Milene Aparecida | de Araújo, Carla Nunes | Santos, Maria Lucília | de Castro, Natália Alves | Charneau, Sébastien | Monnerat, Rose | de Santana, Jaime Martins | Bastos, Izabela Marques Dourado
Aedes aegypti and Culex quinquefasciatus are vectors of diseases that constitute public health problems. The discovery of products capable of inhibiting their development which are less harmful to the environment would have a huge impact on vector control. Here, natural cashew nut shell liquid (CNSL), technical CNSL, anacardic acid, cardanol, and cardol were isolated from Anacardium occidentale and evaluated for larvicidal and pupicidal activity against Ae. aegypti and Cx. quinquefasciatus under laboratory and field conditions. The activities of phenol, resorcinol, salicylic acid, and pentadecane, commercial chemicals similar in structure to nut shell derivatives, were also evaluated. All of the fractions extracted from A. occidentale oil exerted larvicidal effects against both mosquito species (LC₅₀ 5.4–22.6 mg/L), and two of the aforementioned were effective against pupae (LC₅₀ 90.8–109.7 mg/L). Of all the fractions tested, cardol demonstrated the strongest larvicidal and pupicidal effects and presented the most prolonged residual activity against the larvae and pupae of Ae. aegypti and Cx. quinquefasciatus under field conditions. This study suggests that A. occidentale nut shell derivatives are sustainable and promising candidates for the development of novel insecticides to overcome the problem of harmful chemical insecticides.
Mostrar más [+] Menos [-]Antibacterial and anticorrosive properties of CuZnO@RGO waterborne polyurethane coating in circulating cooling water
2019
Jiang, Guofei | Li, Xufei | Che, Yangli | Lv, Yan | Liu, Fang | Wang, Yongqiang | Zhao, Chaocheng | Wang, Xiaojuan
In order to control bacterial adhesion and metal corrosion in the circulating cooling water system, it is necessary to prepare a nanocomposite-modified coating with antibacterial and anticorrosive functions. Copper and zinc composite oxide (CuZnO) was synthesized to prepare CuZnO@RGO nanocomposites. The antibacterial mechanism of CuZnO@RGO nanocomposites was investigated using gram-negative bacteria E. coli and gram-positive bacteria S. aureus as the two model microorganisms. The antibacterial properties of CuZnO@RGO nanocomposites on mixed bacteria were researched in the cooling water system. In addition, the CuZnO@RGO waterborne polyurethane (WPU) composite coating (CuZnO@RGO/WPU) was synthesized. The antibacterial performance, hardness, and corrosion inhibition performance of CuZnO@RGO/WPU composite coating in the cooling water system were also investigated. The results showed that after adding CuZnO@RGO nanocomposites to E. coli or S. aureus suspension, the protein leakage after 20 h was 9.3 times or 7.2 times higher than that in the blank experiment. The antibacterial rate of CuZnO@RGO nanocomposites in circulating cooling water reached 99.70% when the mass fraction of RGO was 15%. When the mass fraction of CuZnO@RGO accounting for CuZnO@RGO/WPU composite coating was 2%, the antibacterial rate, hardness, and corrosion inhibition efficiency were 94.35%, 5H, and 93.30%, respectively.
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