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31.
This work was supported by the Consiglio Nazionale delle Ricerche (Progetto finalizzato Oncologia No. 87.01285.44) and by the Associazione Italiana per la Ricerca sul Cancro (AIRC).  相似文献   
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Bite damage patterns have long been used to estimate shark species and body size, with somewhat limited success. The lack of fit between damage patterns and shark size is partially due to variation in tooth size and shape within an individual. The ability to accurately predict body size from bite patterns is important for better understanding the ecological and behavioral underpinnings of shark bites/attacks on marine organisms, humans, and submarine equipment. To this end, we measured interdental distance (IDD) between the most labial teeth in the first six tooth files on both the upper and lower jaws, as well as the circumference of the portion of each jaw that bears teeth, for prepared jaw sets from fourteen shark species and regressed these data against total length. IDD is allometric as well as an accurate predictor of total length in all species examined, except Carcharhinus acronotus. Tooth-bearing circumference is also allometric and predictive of total length in all species. Though considerable overlap exists in IDD and circumference ranges among species for the total length ranges examined, Carcharodon carcharias and Isurus sp. can be differentiated from Carcharhinus limbatus, Carcharhinus brevipinna, and C. acronotus based on these values alone. When combined with knowledge of species-specific feeding behavior, geographic distribution, and habitat preferences, these simple measures from bite damage patterns allow quick, accurate assessment of shark size and potential species.  相似文献   
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Preference for water quality and its nonmarket valuation can be used to inform the development of pricing policies and long term supply strategies. Tap water quality is a household concern. The objective status quo of water provision varies between households and not between individuals within households, while charges are levied on households not individuals. Individual preferences differ from collective preferences. In households where there are two adults, we examine the preferences of each separately and then as a couple in collective decisions. We show the level of influence each has in developing the collective decision process. We use discrete choice experiments to model preference heterogeneity across three experiments on women, men and on both. We propose a random utility model which decomposes the error structure in the utility of alternatives so as to identify the individual influence in collective decisions. This approach to choice data analysis is new to environmental economics.  相似文献   
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A photocatalyst based on CuO/SiO2 was prepared, and evaluated for the degradation of methylene blue in aqueous medium. The photocatalyst was obtained by calcination method of copper salt, in the presence of silica. The characterization by XRD, FTIR, and TPR techniques confirmed the formation of CuO as active phase. SEM studies showed CuO deposited on the surface of SiO2. By ESI-MS, it was demonstrated that the degradation of methylene blue occurs through successive hydroxylations. Photodegradation assays showed that CuO/SiO2 was efficient for degradation, and that the material worked better in the presence of UV light.  相似文献   
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Environmental Science and Pollution Research - This work evaluates the possibility of cultivating Scenedesmus quadricauda and Chlorella vulgaris microalgae in wastewater from the hydroponic...  相似文献   
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Mesozooplankton group composition was examined in the Northeastern Aegean Sea (NEA) over a grid of 30 stations sampled during July 2004. The surface water layer influenced by the low salinity Black Sea waters (BSW) is considered in this paper. We attempted to study horizontal distribution patterns of major mesozooplankters within a more comprehensive framework, taking into account not only hydrology but also available, concurrently collected data on lower trophic levels (autotrophic and microbial heterotrophic communities). BSW was mainly restricted in the eastern part of the surveyed area where it was entrapped in a ca. 50-km wide anticyclone (the “Samothraki” gyre). High Chlα concentrations, autotrophic biomass as well as abundance and biomass of mesozooplankton were associated with the BSW, with the highest values recorded inside the gyre as well as at its coastal northern periphery and the lowest values towards the western and offshore part of the surveyed area characterized by high salinity waters of Levantine origin. Among mesozooplankters, cladocerans (mainly Penilia avirostris) showed a high abundance within the gyre in contrast to the very low abundance of copepods and appendicularians. Low salinity-high temperature gyre waters were characterized by the dominance of cyanobacteria of the genus Synechococcus in autotrophic biomass and the significant contribution of heterotrophic nanoflagellates in microbial heterotrophic biomass. Based on existing knowledge on ecophysiological traits and prey size-spectra selectivity, we discuss the observed distribution patterns of major mesozooplankton groups in terms of ambient abiotic parameters and the possible biological interactions among these groups as well as with lower or upper trophic levels.  相似文献   
38.
Extractive reserves constitute an innovative approach to match conservation and development objectives, which were originally envisaged as part of a land struggle by forest dwellers in Brazil. In spite of the idea's popularity and the attempts to apply the concept to different tropical regions, there has been little analysis of the combined conservation and development performance of extractive reserve programs. We present a detailed analysis of deforestation and demographic and socioeconomic changes in Alto Juruá, the first extractive reserve created in Brazil in 1990. Forest cover has remained fairly stable. Population has declined slightly, with some internal displacements. The cash economy base has shifted from the original rubber production to a diversified portfolio of agriculture and livestock, and there has been a dramatic rise in nonagrarian income. We conclude that the Reserve represents a very dynamic setting with positive conservation and development outcomes during its first decade.  相似文献   
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Ftorafur is an antimetabolite antitumour drug successfully used for treatment of various tumours. It is generally accepted that ftorafur is converted to 5-fluoruracil. However, some data indicate direct interactions of the compound with DNA. To test this hypothesis we have performed spectrophotometric study of DNA interactions of ftorafur and some of its elementoorganic derivatives with DNA. UV-VIS spectra of the tested compounds were recorded in absence and presence of increasing amounts of DNA. DNA caused a hypochromic effect in spectra of ftorafur, similar, but weaker effect was observed in 5-fluoruracil spectra. Trimethylgermyl derivative of ftorafur manifested a higher DNA-binding capacity compared to ftorafur. To reveal possible mechanism of interaction between the tested nucleosides and DNA ethidium bromide extrusion experiments were performed. It was shown that the compounds did not compete with EBr for intercalation. Fourier transformation infrared spectroscopy analyses revealed decrease in intensity of several bands in spectra of ftorafur, its trimethylgermyl derivative and fluorouracil in presence of DNA indicating again interactions between the compounds and DNA. Docking experiments reveal interactions of the tested nucleosides with the DNA minor groove. Thus ftorafur is capable to interact directly with DNA; further modifications of the molecule enhance this capacity.  相似文献   
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