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71.
The aim of the present study was to investigate the effect of vitamin E on pro/anti-oxidant status in the liver, brain and heart of Newcastle disease virus (NDV) infected chickens. Activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST) and the levels of reduced glutathione and malonaldehyde were estimated in selected tissues of uninfected, NDV-infected and NDV + vit. E-treated chickens. A significant increase in MDA levels in brain and liver (p < 0.05) was observed in NDV-infected chickens when compared to controls. The activities of SOD, CAT, GPx, GR, GST and levels of GSH were significantly (p < 0.05) decreased in brain and liver of NDV-infected chickens over controls. On the other hand, a significant decreased MDA levels and enhanced antioxidant enzyme activity levels were observed in NDV + vit. E-treated animals compared to NDV-infected chickens. Histopathological studies revealed that liver of NDV infected chicken shows focal coagulation and infiltration of hepatocytes, whereas neuronal necrosis and degeneration of Purkinje cells were observed in brain and moderate infiltration of inflammatory cells was observed in heart. However such histological alterations were not observed in NDV + vit. E-treated animals. The results of the present study, thus demonstrated that antioxidant defense mechanism is impaired after the induction of NDV, suggesting its critical role in cellular injury in brain and liver. Further, the results also suggest that vitamin E treatment will ameliorate the antioxidant status in the infected animals. The findings could be beneficial to understand the role of oxidative stress in the pathogenesis of NDV and therapeutic interventions of antioxidants.  相似文献   
72.
Environmental Science and Pollution Research - The present study evaluated the impact of Saharan dust event on particulate matter (PM: PM10 and PM2.5) concentrations by analyzing the daily average...  相似文献   
73.
Environmental Science and Pollution Research - This article predicts the operational temperature of a 1-MWp rooftop photovoltaic (PV) system installed on buildings of GITAM University, Andhra...  相似文献   
74.
Novel bio-based green films were prepared using wheat protein isolate (WPI) by solution casting method using Propylene Glycol as a plasticizer for packaging applications. The effect of the plasticizer content (10, 15, 20 and 25 wt%) on mechanical properties (tensile strength, young’s modulus and  % of elongation) was investigated. A thermal degradation and phase transition of the prepared WPI was assessed by means of TGA and DSC analysis. The results showed that the tensile strength and young’s modulus decreased and  % of elongation increased with increasing PG content. The ATR-FTIR and SEM were used for structural characterization and morphology of the films, respectively. FTIR studies reveals that the intensity of the bands corresponding to the amide groups increases with increasing PG content tending to increase protein–PG interactions. Further, the glass transition temperature was decreased and the thermal stability of the WPI was found to be increased by plasticization. The overall thermal stability of the films was improved and is attributed to the increase in mobility of the polymer chains.  相似文献   
75.
Power plants employ chlorination for controlling biofouling in the cooling water system. Phytoplankton drawn into the cooling water system could be impacted by chemical stress induced by the oxidizing biocide. It is likely that microalgae, being sensitive to chlorine, could suffer damage to their cellular structure and function. In this study, we present data on the effect of in-use concentrations of chlorine on the unicellular microalga, Chlorella salina. Chlorophyll autofluorescence was measured in terms of mean fluorescence intensity per cell for rapid assessment of toxicity. Viability of the cells exposed to chlorine was determined by fluorescein diacetate staining. Functionality of the photosynthetic machinery was assessed by gross primary productivity. Results from the study, which combined confocal laser scanning microscopy with image analysis, showed a significant dose-dependant reduction in chlorophyll autofluorescence, esterase activity and gross primary productivity in chlorine-treated cells. Interestingly, the cells injured by chlorination could not recover in terms of autofluorescence, esterase activity or productivity even after 18 h incubation in healthy media. Among the test points evaluated, esterase activity appeared to be sensitive for determining the chlorination-induced impact. Our results demonstrate that low-dose chlorination causes significant decrease in chlorophyll autofluorescence, intracellular esterase activity and primary productivity in Chlorella cells.  相似文献   
76.
The toxic form of methylmercury is of concern in terms of its neurotoxicity, genotoxicity and reproductive toxicity. Extensive research has been carried out on the effects of exposure to high levels of this toxic compound, but this is not true for research on exposure to lower levels. The harmful effects of methylmercury are a cause for concern irrespective of the exposure levels. The problem becomes more serious because of biomagnifications of methylmercury. Disorders may develop during neonatal stage and then develop further during the lifetime. The common effects which can be seen are retarded brain development and permanent disorders like cerebral palsy. This can also cause neurogenerative disorders like Alzheimer’s and Parkinson’s. Research on animals has also shown toxicity. Inorganic Hg was found to be present in brains of neonatal rats, in monkeys prenatal exposure to MeHg resulted in a reduced number of births, and birds laid a lesser number of eggs and the infant mortality rate was higher.  相似文献   
77.
Lin YC  Panchangam SC  Wu CH  Hong PK  Lin CF 《Chemosphere》2011,82(4):502-506
Due to their potential toxicity and odourous nature, the residual organics in municipal solid waste incinerators are recently gaining attention as an important issue of resources recovery apart from their complex mixture of organic counterpart. Studies of the organic fractions in municipal solid waste incinerator residues have been limited. In this study, extended solid-phase extraction of the water-washed bottom ash and liquid-phase extraction of the washing water were carried out with regard to bottom ash samples from three mass-burning incinerators in Taipei County (Taiwan) during four consecutive seasons of year 2008-2009. Supercritical fluid extraction and Soxtec extraction techniques along with GC-MS were successfully used to characterize the residual organics in weathered and washed bottom ashes. Supercritical fluid extraction provided the quantification of aliphatics and aromatic compounds such as hexanoic acid and benzaldehyde, respectively. Soxtec extraction was useful for qualitative analysis of aromatic and aliphatic groups in the ashes and many of which were odourous and toxic compounds. By mixing one unit weight (g) bottom ash with two unit volume (mL) water for 15 min, total organic carbon in the bottom ash was greatly reduced (e.g., from 4.1 to 1.8 wt.%). Among the removed were foul odour-causing compounds such as pyridine and quinoline derivatives, while some aromatic compounds such as 4-hydroxybenzaldehyde and low-molecular-weight aliphatics such as hexanoic acid remained. The results here suggest that washing with water can be an effective pre-treatment step for removing odour-causing and environmental concerned organics.  相似文献   
78.
The phosphorus (P) in agro-industrial by-products--a potential source of freshwater eutrophication but also a valuable fertilizer--needs to be speciated to evaluate its fate in the environment. We investigated to what extent X-ray absorption near edge structure (XANES) spectroscopy at the P K- and L2.3-edges reflected differences in sequentially extracted filter cakes from sugarcane (Saccharum officinarum L.) (FIC) and niger seed (Guizotia abyssinica Cass.; NIC) processing industry in Ethiopia. The P fractionation removed more labile (54%) and H2SO4-P (28%) from FIC than from NIC (18% labile, 12% H2SO4-P). For the FIC residues after each extraction step, linear combination (LC) fitting of P K-edge spectra provided evidence for the enrichment of Ca-P after the NaOH-extraction and its almost complete removal after the H2SO4-treatment. The LC-fitting was unsuccessful for the NIC samples, likely because of the predominance of organic P compounds. The different proportions of Ca-P compounds between FIC (large) and NIC (small) were more distinctive in L2-than in the K-edge XANES spectra. In conclusion, the added value of complementary P K- and L2.3-edge XANES was clearly demonstrated, and the P fractionation and speciation results together justify using FIC and NIC as soil amendments in the tropics.  相似文献   
79.
Environmental Science and Pollution Research - Operational energy use and energy-based GHG emissions of air-conditioning in the building sector are increasing aggressively due to occupants’...  相似文献   
80.
Journal of Polymers and the Environment - Cellulose nanopaper (CNP) is a new potential candidate for flexible biopolymer substrate made of nanocellulose (NC). We systematically studied the effect...  相似文献   
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