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651.
The main purpose of the present work is to study the concentration of atmospheric particles in the Candiota region, in the state of Rio Grande do Sul, where the Presidente Médici coal power plant is located. Aerosol samples were collected at the studied locations between December 2000 and December 2001 during 24 h periods at 15 day intervals using HV PM10 and dichotomous samplers. Then, the values obtained with the ISCST (Industrial Source Complex Term) model, with the HV PM10 sampler at all studied stations, and with the dichotomous sampler at the 8 de Agosto station were compared with each other. The results show that the values for the model had been underestimated in relation to the HV PM10 data for the studied stations, but agreed with the values obtained with the dichotomous sampler.  相似文献   
652.
This paper verifies the effects of urbanization on the original levels of environmental gamma radiation in an anomalous area. The fieldwork was done in the city of Guarapari, on the seacoast of the state of Espírito Santo, Brazil. This place was chosen because the whole region is naturally rich in monazite sand, which contains thorium and uranium. A similar study was also carried out in the 1960s. The measurements were done using an inorganic NaI scintillometer detector with Cu+Pb filters coupled to a scaler. The methodology of measurements used was similar to the one applied in the fieldwork carried out in the 1960s. In addition, a simulation was performed in the laboratory, to determine the attenuation of the materials used in the urbanization of the region. The results of this work clearly show that there was a reduction in the levels of external radiation in the streets and squares of Guarapari. It was concluded that the reduction was due to attenuation by the materials used in the urbanization.  相似文献   
653.
European eel (Anguilla anguilla L.) were caged and exposed in situ for 8 and 48 h to the Aveiro offward fishing harbour water (HW) and to clean seawater under laboratory conditions (Control). Eel liver biotransformation (Phase I) was measured as ethoxyresorufin-O-deethylase (EROD) activity, cytochrome P450 (P450) and glutathione S-transferase (GST) activity (Phase II). Genotoxic responses were determined as blood, liver and kidney DNA strand breaks as well as erythrocytic nuclear abnormalities (ENAs). HW failed to significant increase liver EROD, GST activities and ENA frequency. Nevertheless, P450 content was significantly increased after 8 and 48 h exposure. Genotoxicity measured as DNA integrity decrease was found in blood after 8 and 48 h exposure to HW, whereas in liver and kidney, it was observed after 48 h exposure to HW. Blood, kidney and liver genotoxicity may be due to the presence of polycyclic aromatic hydrocarbons (PAHs) which are genotoxic compounds and the main HW organic contaminants.  相似文献   
654.
Anguilla anguilla L. ethoxyresorufin-O-deethylase (EROD) elevation by 2.7 microM beta-naphthoflavone (BNF) 3 days water exposure, or 4 mg/kg ip exposure, was studied in four different organs--liver, kidney, gills, and intestine. The results demonstrated a significant increase in liver EROD activity for the two previous conditions, whereas kidney EROD activity only increased during the intraperitoneal exposure. A. anguilla was also exposed during 8, 16, and 24 h to water contaminated with 2.7 microM BNF or benzo[a]pyrene (BaP) at 20 degrees C and 25 degrees C. Both compounds significantly increased liver EROD activity from 8 up to 24 h. There was no significant difference in liver EROD activity elevation by both compounds, either at 20 degrees C or 25 degrees C. Liver EROD activity was demonstrated to be one of the first warning systems concerning the presence of polycyclic aromatic hydrocarbons (PAHs) in water. A. anguilla 3 h exposure to diesel oil water-soluble fraction (DWSF) significantly increased plasma cortisol and significantly decreased plasma lactate. A prolonged exposure beyond 3 h, i.e. 4 h, 2, 3, 4, and 6 days to the previous conditions demonstrated a significant liver EROD activity elevation from Day 2 up to 6, and a significant increase in erythrocytic nuclear abnormalities (ENA) at Day 6.  相似文献   
655.
Urban floods from thunderstorms cause severe problems in Metro Manila due to road traffic. Using Light Detection and Ranging (LiDAR)-derived topography, flood simulations and anecdotal reports, the root of surface flood problems in Metro Manila is identified. Majority of flood-prone areas are along the intersection of creeks and streets located in topographic lows. When creeks overflow or when rapidly accumulated street flood does not drain fast enough to the nearest stream channel, the intersecting road also gets flooded. Possible solutions include the elevation of roads or construction of well-designed drainage structures leading to the creeks. Proposed solutions to the flood problem of Metro Manila may avoid paralyzing traffic problems due to short-lived rain events, which according to Japan International Cooperation Agency (JICA) cost the Philippine economy 2.4 billion pesos/day.  相似文献   
656.
Environmental Science and Pollution Research - Socioeconomic and demographic factors, lifestyle and cultural characteristics may play an important role in the development of genetic damage. This...  相似文献   
657.
Environmental Science and Pollution Research - Imazethapyr, a selective systemic herbicide, is widely used in agriculture and it is frequently detected in water bodies close to application areas....  相似文献   
658.
Environmental Science and Pollution Research - Occupational exposure to pesticides has been identified as a major trigger of the development of cancer. Pesticides can cause intoxication in the...  相似文献   
659.
Journal of Material Cycles and Waste Management - Montmorillonite clays such as bentonites are often studied and used as reinforcement to thermoplastics, since it can generate nanostructures,...  相似文献   
660.
Journal of Polymers and the Environment - Starch is the main predominant food reserve in plants. Its characteristics stand out from other carbohydrates providing it with several industrial...  相似文献   
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