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541.
Agreement on the criteria for granting the right to use water resources between governing bodies represents a significant advance in the process of sharing water use. To aid water resource management agencies in optimizing water use, the impact of using different criteria for permitting water use in the Paracatu river basin, Brazil, was evaluated in this study. The streamflow criteria corresponding to 30 % of the annual Q7,10 (used by the governing body of Minas Gerais), 70 % of the annual Q95 (used by the governing body of the union), 30 % of the monthly Q7,10, and 70 % of the monthly Q95 were evaluated. The use of criteria based on the monthly streamflow allows for better management of water use because it allows for greater utilization of this resource in times when there is high water availability and imposes a more realistic restriction during critical periods. Substitution of the annual Q7,10 for the monthly Q7,10 significantly increases the streamflow permitted in some months, for example, from December to May. Use of the criterion of 70 % of the annual Q95 involves a high risk of drought in critical months, while the criterion of 70 % of the monthly Q95 minimizes this risk.  相似文献   
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Abstract

The fulvic acid (fua) fractions of two samples of composted solid wastes [urban (urfua) and livestock (lsfua) wastes], commercialized to be used in agriculture as organic correctives or fertilizers, were analyzed for their affinity towards Cu(II) at pH=6. Molecular fluorescence spectroscopy (synchronous mode) was used to monitor the quenching caused by the complexation upon addition of Cu(II) to fua. Spectral data were preprocessed by a chemometric self‐modeling mixture analysis method (SIMPLISMA) to detect the number of different types of fluorescent binding sites that exist in each fua, their spectra and the corresponding quenching profiles [fluorescence intensity as function of the total Cu(II) concentration]. From the analysis of the quenching profiles, the amount of binding sites (Cl) and the corresponding conditional stability constants (K') were calculated. Both fua samples have approximately Cl = 0.21 mmol/g and the logarithms of K’ are 4.21(3) and 4.51(8), respectively for urfua and lsfua. The differences detected between these fua samples and those extracted from natural soils can be attributed mainly to the relatively small humification extent of the present anthropogenic fua samples.  相似文献   
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The development of methods for process analysis has contributed to the improvement of production systems. In this context, many models and methodologies have been established in the literature in order to evaluate environmental performance of industrial processes, since it has become an important issue for society. However, few of them analyze environmental impacts and related costs simultaneously. So, this work presents an integrated methodology to perform this evaluation, based on Life Cycle Assessment (LCA) and Activity-Based Costing (ABC) principles. The proposed methodology was applied in a metallurgical industry in Brazil. As result, it allowed to identify the production process stages which have critical environmental impacts and greatest contribution to increase environmental costs of the company.  相似文献   
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Gromia is a large marine protist with filose pseudopodia and ovoid test, common in coastal intertidal and sublittoral waters. Although deep-water Gromia-like morphospecies were discovered in the 1990s, their relations to the shallow water species have never been established. Moreover, very little is known about the diversity within Gromia, reflecting the fact that these morphologically relatively simple protists have few characters useful for species identification. Consequently, we have analysed the SSU rDNA and ITS rDNA genes to examine gromiid diversity in two different areas located on the Oman and Pakistan margins of the Arabian Sea (water depths 1,000–2,000 m). In total, 27 deep-sea gromiid sequences of the SSU rDNA gene and six sequences of the ITS rDNA region were obtained. Our data confirm that Gromia-like protists from the bathyal deep sea are related to the shallow-water gromiids. Within Arabian Sea Gromia, we identified seven distinctive lineages, five of which form a monophyletic group branching as a sister group to shallow-water species. Six lineages of Arabian Sea Gromia can be defined morphologically, while one lineage includes specimens that look identical to specimens from two other lineages. This indicates that each Gromia lineage represents probably a separate species and suggests that deep-sea gromiid diversity is higher than indicated by their simple morphology.  相似文献   
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Selection favors females that attend to reliable information about male genetic quality and fitness. Male nutritional condition can be a significant sign of mate quality since poor nutrition can be related to reduced sperm quality, low sperm quantity, sexually transmitted diseases, and parasites. We tested whether female Nile tilapia, Oreochromis niloticus, preferred the chemical cues of males that were well fed with high-protein diet over those fed with low-protein diet. Females do not only discriminate between males but also show a preference for well-fed males, discriminating between the odors with respect to nutritional state, suggesting that they were responding to a food-specific chemical cue. It is therefore likely that nutritional condition is related to the production of pheromones in males. Our results suggest that information about male nutritional state can be conveyed in chemical cues and that females attend to these cues during mate choice.  相似文献   
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