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The embryonic development and the level of dependency of the embryos from the maternal organism were investigated for Centroscymnus coelolepis. During the development, there is a 22–32% loss of organic matter and gains of 95–122% and 29–46% on moisture and inorganic matter, respectively. Only 28–48% of the initial yolk energy is conserved in embryos, being the remaining used in catabolism. In late pregnancy, the epithelium thickness of uterine villi decreases and vascularity increases. Results suggest that only water and minerals are transferred from the mother to the embryos. Monounsaturated fatty acids are the main type of fatty acids representing 48% of the total yolk fatty acid content, followed by polyunsaturated (30%) and saturated fatty acids (18–21%).  相似文献   
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In the present paper, the current beach management framework in the North-Western Mediterranean coast (Catalonia, Spain) was revised. Beach management was analyzed using the concepts of Integrated Coastal Zone Management (ICZM). The history of beach management in the second half of the 20 century and the new developments in the academic field and in the practical beach management sector during the last decade were studied. The revision of legal texts and strategies in the Catalan coast allowed synthesizing all scattered information affecting beach management. A SWOT analysis was performed. The main strengths of the beach management framework in Catalonia are the public ownership of beaches, which allows the government to carry out a comprehensive management and the recent data and analysis provided by the adopted National and Autonomous ICZM strategies. The weaknesses found were related to the functioning of traditional existing institutions. New opportunities are related to the possibility of establishing new institutions that conduct a more inclusive and proactive management. The main threat is that although the possibility for a fundamental change in beach management organization exists, resources available are not fully exploited.  相似文献   
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The aim of this work was to assess possible effects of the Prestige oil spill on reproduction parameters of mussels along the Galician and Bay of Biscay coast. Studied endpoints included sex ratio, gonad histology and vitellogenin-like proteins using the alkali-labile phosphate (ALP) method. A high prevalence of haemocytic infiltration of follicles and severe oocyte atresia was found in most localities in April 2003. Spawning gonads were observed in most impacted populations in the same sampling. In April 2004 mature small sized follicles were observed. No histopathological changes were observed in April 2005 and 2006, except a high prevalence of necrotic gametes in 6 out of 22 localities in April 2006. Female ALP levels showed high interindividual variability in April 2004, which was reduced in April 2005 and 2006. No xenoestrogenic effects were observed in male mussels. Overall, gamete alterations were detected during 2003-2004 and a recovery trend was observed afterwards.  相似文献   
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The manufacturing of orange juice generates high volumes of orange peel waste which should not be deposited in landfill according to current recommendations. Furthermore, glycerol is a compound co-generated in biodiesel manufacturing, but the volume generated is higher than the current demand for pure glycerol. The anaerobic co-digestion of orange peel waste with residual glycerol could reduce the inhibitory effect of some compounds and provide a correct nutrient balance. Under mesophilic temperature and semi-continuous conditions, a mixture of orange peel waste-residual glycerol of 1:1 (in COD) operated favorably for organic loads up to 2.10 g VS/L. At higher organic loads, the accumulation of volatile fatty acids (VFA) and a decrease in the pH caused process destabilization. The methane yield coefficient was quite constant, with a mean value of 330 ± 51 mLSTP/g VSadded, while the organic loading rate (OLR) reached a mean value of 1.91 ± 0.37 kg VS/m3 d (17.59 ± 2.78 kg mixture/m3 d) and the hydraulic retention time (HRT) varied in a range of 8.5–30.0 d.  相似文献   
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