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151.
Conclusions  The results are at least as good as those obtained with much more sophisticated models. Furthermore, the models can be easily run on a simple PC. This approach may provide a good diagnostic network (as seen in Bilbao) with real-time, short-term prognostic capabilities for a given location. The models have been built for Bilbao and are applicable only in this location. However, using the same methodology, similar results could be obtained in other environments if a good diagnostic network is available. The full paper is published in the Internet journal ‘Gate to EHS (Environmental and Health Science)’, in June 2001, and can be called up and cited by way of the DOI:http://dx.doi.org/10.1065/ehs2001.06.009  相似文献   
152.
Abstract

Five organophosphorous insecticides: Leptophos, EPN, Cyano‐fenphos, trichloronate and salithion proved to cause irreversible ataxia not only to chicken but also to mice and sheep. TOCP was included as a reference. Cyanofenphos blocked the catecholamine B‐receptor binding activity with 3H‐norepinephrine at a level similar to that of the specific inhibitor propranolol in the mouse heart preparation. In the lamb heart preparation, the B‐receptor was more sensitive to Leptophos, salithion and TOCP than to propranolol. The six compounds and their oxons were screened for their in‐vitro inhibition to monamine oxidase (MAO), acetyl cholinesterase (AChE) and neurotoxic esterase (NTE) in the brain of either mouse, lamb or chicken. It is believed that their AChE inhibition stands for their acute toxicity, while NTE inhibition is responsible for their paralytic ataxia.  相似文献   
153.
The limited water resources of Egypt lead to widespread water-stress. Consequently, the use of marginal water sources, such as agricultural drainage waters, provides one of the national feasible solutions to the problem. However, the marginal quality of the drainage waters may restrict their use.The objective of this research is to develop a tool for planning and managing the reuse of agricultural drainage water for irrigation in the Nile Delta. This is achieved by classifying the pollution levels of drainage water into several categories using a statistical clustering approach that may ensure simple but accurate information about the pollution levels and water characteristics at any point within the drainage system.The derived clusters are then visualized by using a Geographical Information System (GIS) to draw thematic maps based on the entire Nile Delta, thus making GIS as a decision support system. The obtained maps may assist the decision makers in managing and controlling pollution in the Nile Delta regions. The clustering process also provides an effective overview of those spots in the Nile Delta where intensified monitoring activities are required. Consequently, the obtained results make a major contribution to the assessment and redesign of the Egyptian national water quality monitoring network.  相似文献   
154.
Abstract

Cotton‐producing areas of the Centrol Sudan, bordered by the Blue and the White Nile, have been subjected to repeated applications of pesticides. This region is irrigated by a series of canals, the Gezira canals, which hold large amounts of fresh water. Lake Nubia at the Sudan‐Egypt border is another important fresh water reservoir and fisheries ground. Fish from both the Gezira and Lake Nubia showed elevated concentrations of pesticides, suggesting that continued pesticides application would endanger the equatic fauna of this region and the proposed fresh water fishery.  相似文献   
155.
Relationships between abundance of basic net phytoplankton taxonomic groups (cyanobacteria, diatoms, and chlorophytes) and nutrient concentrations in water were studied on the Pas??ka River in years with varied water levels. In high water level conditions, large amounts of orthophosphates and total nitrogen from the catchment could favor development of cyanobacteria and chlorophytes. The species could be allochthonic. At low water levels, the factor stimulating phytoplankton development could be nutrients coming from mineralization of accumulated organic matter. The highest nutrient concentrations could favor diatom development. In such conditions, dominant taxa were autochthonic. In terms of numbers, F. capucina was dominant, and in terms of biomass—genus Spirogyra sp. It could come from plant periphyton inhabiting the concrete drops of the dam included in the river’s development in the vicinity of the hydroelectric power station.  相似文献   
156.
Designing a proper acoustical environment—indispensable to speech recognition—in long enclosures is difficult. Although there is some literature on the acoustical conditions in underground stations, there is still little information about methods that make estimation of correct reverberation conditions possible. This paper discusses the assessment of the reverberation conditions of underground stations. A comparison of the measurements of reverberation time in Warsaw’s underground stations with calculated data proves there are divergences between measured and calculated early decay time values, especially for long source–receiver distances. Rapid speech transmission index values for measured stations are also presented.  相似文献   
157.
Journal of Material Cycles and Waste Management - In recent years, the use of residue for the production of new composite materials has gained prominence as it enables reuse of materials and...  相似文献   
158.

Despite the association between tobacco use and the harmful effects on general health as well as male fertility parameters, smoking remains globally prevalent. The main content of tobacco smoke is nicotine and its metabolite cotinine. These compounds can pass the blood-testis barrier, which subsequently causes harm of diverse degree to the germ cells. Although controversial, smoking has been shown to cause not only a decrease in sperm motility, sperm concentration, and an increase in abnormal sperm morphology, but also genetic and epigenetic aberrations in spermatozoa. Both animal and human studies have highlighted the occurrence of sperm DNA-strand breaks (fragmentation), genome instability, genetic mutations, and the presence of aneuploids in the germline of animals and men exposed to tobacco smoke. The question to be asked at this point is, if smoking has the potential to cause all these genetic aberrations, what is the extent of damage? Hence, this review aimed to provide evidence that smoking has a mutagenic effect on sperm and how this subsequently affects male fertility. Additionally, the role of tobacco smoke as an aneugen will be explored. We furthermore aim to incorporate the epidemiological aspects of the aforementioned and provide a holistic approach to the topic.

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159.
160.
This study forms part of the Action Plan for the Conservation of Marine Vegetation in the Mediterranean SEa (United Nation Environmental Program). It was carried out in June 2000 in the Farwà Lagoon, Libya. The mapping of the main benthic vegetation was achieved by compiling the field observations (transect method), and remote sensing of SPOT satellite images. The phytobenthos in the Farwà lagoon covers an area of 1820 ha (65%). Three benthic macrophyte species dominate, namely the marine phanerogamsCymodocea nodosa andPosidonia oceanica, and the algaCaulerpa prolifera. DeadPosidonia oceanica leaves (litter) form veritable mounds in the vicinity of the openings leading to open sea. These leaves, which come from the coastal sea, are brought into the lagoon by currents and tides; their decomposition will lead to high oxygen consumption and the release of hydrogen sulphide. The phenological data ofPosidonia oceanica shoots sampled in the lagoon are similar to those from other stations in the Mediterranean. Conversely, the lepidochronological parameters of shoots sampled in the central part of the lagoon exhibit values that are substantially higher than those generally recorded in the Mediterranean. The mean number of leaves produced annually is 9.9 (mean value for the Mediterranean: 7.5) and the rhizome growth rate is of 35.7 mm.yr−1 (mean value for the Mediterranean: 7.5 mm.yr−1). This hypersaline environment would seem to provide optimum growth conditions for the speciesPosidonia oceanica.  相似文献   
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