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21.
World landings of fish and shellfish are approaching 100 million metric tons (MMT) annually. Of this total, around 28% is processed into fish meal and oil. Economic pressures due to poor landings, low prices in traditional markets and high fuel costs have forced the industry to seek new markets and products that can take advantage of the unique properties of fish proteins and oils. Fish meal processing continues to evolve. Fresh raw materials and new, low-temperature processing techniques lead to products with excellent nutritional value. These new, special meals are finding uses in feeding farmed fish, early-weaned pigs, ruminants and pets. Fish oils, whether present as fat in the fish meal or as separated oil, are rich in ω3 fatty acids. When fed to food animals, these ω3 fatty acids deposit in the meat and depot fat. Concepts for poultry with an equivalent amount of ω3 fatty acids to lean fish are being developed. Eggs with a high ω3 fatty acid content and good functionality and flavor are under evaluation. Catfish with shelf-stable flavors and high ω3 fatty acids are also under study. ω3 Fatty acids may affect the immune function of livestock. Future research will evaluate the overall immune function of animals, including resistance to disease, survival under stress and hatchability.  相似文献   
22.
Secondary analysis of the 2007 Australian National Children’s Nutrition and Physical Activity survey was undertaken to assess the intake and food sources of EPA, DPA and DHA (excluding supplements) in 4,487 children aged 2–16 years. An average of two 24-h dietary recalls was analysed for each child and food sources of EPA, DPA and DHA were assessed using the Australian nutrient composition database called AUSNUT 2007. Median (inter quartile range, IQR) for EPA, DPA and DHA intakes (mg/day) for 2–3, 4–8, 9–13, 14–16 year were: EPA 5.3 (1.5–14), 6.7 (1.8–18), 8.7 (2.6–23), 9.8 (2.7–28) respectively; DPA 6.2 (2.2–14), 8.2 (3.3–18), 10.8 (4.3–24), 12.2 (5–29) respectively; and DHA 3.9 (0.6–24), 5.1 (0.9–26), 6.8 (1.1–27), 7.8 (1.5–33) respectively. Energy-adjusted intakes of EPA, DPA and DHA in children who ate fish were 7.5, 2 and 16-fold higher, respectively (P < 0.001) compared to those who did not eat fish during the 2 days of the survey. Intake of total long chain n-3 PUFA was compared to the energy adjusted suggested dietary target (SDT) for Australian children and 20 % of children who ate fish during the 2 days of the survey met the SDT. Fish and seafood products were the largest contributors to DHA (76 %) and EPA (59 %) intake, while meat, poultry and game contributed to 56 % DPA. Meat consumption was 8.5 times greater than that for fish/seafood. Australian children do not consume the recommended amounts of long chain omega-3 fatty acids, especially DHA, which could be explained by low fish consumption.  相似文献   
23.
Kraffe E  Grall J  Le Duff M  Soudant P  Marty Y 《Lipids》2008,43(10):961-970
Thirty-five species of marine mollusk bivalves were analyzed for their fatty acid (FA) composition of cardiolipin (Ptd(2)Gro). All species showed a Ptd(2)Gro with strong selectivity for only a few polyunsaturated fatty acids, but three characteristic FA profiles emerged, with clear parallels to bivalve phylogeny. A first group of 12 species belonging to the Eupteriomorphia subgroup (Filibranchia) was characterized by a Ptd(2)Gro almost exclusively composed of 22:6n-3, whereas in the four Filibranchia Pteriomorph species analyzed, this FA was combined with substantial proportions of 18:2n-6 and 18:3n-3. Finally, a third group of 20 species, all belonging to the Heterodonta subclass, possessed Ptd(2)Gro containing predominantly both 22:6n-3 and 20:5n-3. Polyunsaturated FA moieties and arrangements in the Ptd(2)Gro of some marine species investigated in other classes of the mollusk phylum (Gastropoda, Polyplacophora) were found to be different. The present results suggest that the specific Ptd(2)Gro FA compositions in bivalves are likely to be controlled and conserved in species of the same phylogenetic group. Functional significances of the evolution of this mitochondrial lipid structure in bivalves are discussed.  相似文献   
24.
本文着重介绍了DHA、EPA的来源,特别是生理机能及其在人体内的代谢过程,并详细论述了DHA、EPA在乳品行业中应用的意义及工艺中存在的问题。  相似文献   
25.
Iron(II) analyses using bathophenanthroline are shown to be characterized by an inherent, small positive interference when the pH of analysis is below 6.5 and iron(III) is present. The interference, which is due to a colored complex formed in the presence of FeOH2+ and bathophenanthroline, varies in magnitude according to the presence or generation of FeOH2+ during analysis. This interference necessitates reconsideration of published claims that low levels of stable iron(II) exist in oxygenated natural waters, particularly the surface layers of lakes.  相似文献   
26.
综述了近年来人们用超临界二氧化碳(SC-CO_2)从鱼油中富集提纯EPA(廿碳五烯酸)和DHA(廿二碳六烯酸)的各类实验装置。讨论了鱼油的预处理方法、萃取操作条件对SC-CO_2提纯EPA和DHA的纯度和收率的影响。介绍了一个工业化双塔连续逆流萃取模拟流程。对我国鱼油资源的利用进行了分析。  相似文献   
27.
28.
王静  徐皑冬  宋岩 《计算机工程》2009,35(6):176-177
现场总线在通信传输过程中,会受到各种通信故障的影响,而现场总线与功能安全的结合可降低这种影响。该文描述EPA功能安全通信模型,针对通信传输过程中可能出现的通信错误,采用时间戳、序列号、CRC校验等功能安全通信技术。给出EPA功能安全协议层的报文结构,阐述功能安全协议层的具体实现过程。  相似文献   
29.
马萨诸塞州诉环保署一案,是美国近年来备受关注的一个新型的环境诉讼即气候变化诉讼的经典判决,也是联邦最高法院受理的第一个气候变化诉讼。美国联邦最高法院于2007年4月就马萨诸塞州等诉环保署案做出判决后,在美国国内产生广泛影响[1],对我国行政型环境公益诉讼在起诉资格审查、裁判请求权保障、裁判理由充分公开等方面均有可借鉴之处[2]。  相似文献   
30.
低压集抄系统主站通信规约的研究   总被引:1,自引:0,他引:1  
目前在低压电力用户集中抄表系统建设中,主站和集中器之间的数据通信协议并无相应国家和行业标准可循。为增强该系统的互操作性,在借鉴IEC 60870-5-102协议基础上,结合国内低压电力用户集中抄表系统的实际,形成了一种满足居民集抄系统应用需求的简明、高效的主站通信协议,基于该通信协议开发的抄表管理软件,在湖北省地市供电公司低压电力用户集中抄表系统建设中运行稳定、可靠。文章对规约结构进行了详细说明,并给出链路传输应用示例。  相似文献   
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