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The fatty acid compositions of total polar and total neutral lipids of Atlantic herring eggs and larvae were determined immediately
before fertilization, after fertilization and at various times during subsequent embryonic and early larval development. Within
3 hr after fertilization the percentage of total PUFA in neutral lipid decreased from 33% to 20%, with a reciprocal increase
in monoenes. Thereafter the percentage of PUFA in the neutral lipids increased progressively, attaining the original level
in ripe eggs by the time of yolk sac absorption. During the larval stages the percentage of PUFA continued to increase in
the neutral lipid, reaching almost 44% of the total by day 32 after fertilization, although it was reduced to 32% by day 36.
The percentage of monoenes in the neutral lipid displayed a progressive decrease during the whole period of development from
3 hr after fertilization. Throughout all the developmental periods the fatty acid composition of total polar lipids remained
essentially constant. The polar lipids of the yolk sac displayed virtually the same fatty acid composition as the larval bodies,
but the neutral lipids of the yolk sac were low in PUFA compared to the larval bodies. The results are discussed with reference
to changes in lipid class composition during development. The conservation of high levels of PUFA in lipids during embryogenesis
and early larval development reflects the importance of these fatty acids during development. 相似文献
3.
The performances of two systems using hydrocarbon pairs are compared. The first system is an absorption heat pump, comprising a rectification column separator and a mixer comprising a single-stage cell. In this case, five hydrocarbon pairs are used. In the second system, the authors compare the performances of three hydrocarbon pairs in two heat pumps with one or two stages in the mixer. It was shown that the best performances are obtained using pairs with the most similar chemical compositions. 相似文献
4.
T. Rocklin (see record 1994-29650-001) examined the relations between M. Goff and P. L. Ackerman's (see record 1993-13529-001) measure of typical intellectual engagement (TIE) and a personality test measure of Openness. Rocklin's arguments are examined in the context of 3 themes: philosophical issues, TIE and Openness from a facet perspective, and the bandwidth-fidelity dilemma. Although Rocklin raised important issues about these constructs, it is demonstrated that measures of TIE and Openness, although significantly related, are theoretically and empirically distinguishable. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
A possible structure of the casein micelle based on high-resolution field-emission scanning electron microscopy 总被引:2,自引:0,他引:2
Douglas G. Dalgleish Paul A. Spagnuolo H. Douglas Goff 《International Dairy Journal》2004,14(12):1025-1031
New electron micrographs, produced using the technique of Field Emission Scanning Electron Microscopy, showing the details of the micellar surface, are presented. The images show the micellar surfaces without any coating, and suggest that the surface of the micelle may have a much more complex structure than has previously been demonstrated. Although there appear to be no spherical subunits (submicelles), there is evidence for the organization of the caseins into tubular structures within the micelle. The surface is not smooth, and contains gaps between the substructures. The observations are discussed in terms of published models of micellar structure, where is it suggested how the depiction of the micellar surface can be used to explain certain factors of its reactivity and behaviour. 相似文献
6.
We show for the first time that signal processing schemes based on noncoherent signal addition will require signal transfer characteristics exhibiting high degrees of curvature. We quantify this by proposing a set of single-input, dual-output, power-conserving transfer functions and generating designs based on these characteristics. We then analyze the sensitivity of such a design scheme to nonidealities in the signal level and device behavior, and show that a sampling operation is only possible for transfer characteristics with residual "low" output of less than about 10% and low intensity reflectivity higher than 98%. For single device signal loss of up to 0.1 dB, we show that the best possible crosstalk-to-noise ratio in a packet forwarder (27 dB), is limited by the availability of the sampling operation. 相似文献
7.
KL Goff 《Canadian Metallurgical Quarterly》1998,8(3):733-744
Enteral nutrition is a therapy provided routinely in the hospital, extended care, and home care settings for patients who are unable to maintain adequate oral nutrition yet have a functioning gastrointestinal tract. Information about the cost and effectiveness or benefits of enteral nutrition in the hospital and home care settings is important to know when making decisions about providing this therapy. This article discusses the methods used in cost analysis, explains the difference between cost and charges, and reviews the current information known about the cost-effectiveness and cost-benefits of enteral nutrition in the acute-care setting and at home. 相似文献
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Jun Pan Li Na Quan Yongbiao Zhao Wei Peng Banavoth Murali Smritakshi P. Sarmah Mingjian Yuan Lutfan Sinatra Noktan M. Alyami Jiakai Liu Emre Yassitepe Zhenyu Yang Oleksandr Voznyy Riccardo Comin Mohamed N. Hedhili Omar F. Mohammed Zheng Hong Lu Dong Ha Kim Edward H. Sargent Osman M. Bakr 《Advanced materials (Deerfield Beach, Fla.)》2016,28(39):8718-8725