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21.
Dietary Monounsaturated Fatty Acids Are Protective Against Metabolic Syndrome and Cardiovascular Disease Risk Factors 总被引:1,自引:2,他引:1
Over 50 years of research has sought to define the role dietary fat plays in cardiovascular disease (CVD) risk. Although optimal
dietary fat quantity has been keenly pursued over past decades, attention has recently centered on the value of dietary fat
quality. The purpose of the present review is to provide a critical assessment of the current body of evidence surrounding
efficacy of dietary monounsaturated fatty acids (MUFA) for reduction of traditional risk factors defining metabolic syndrome
(MetS) and CVD. Due to existing and emerging research on health attributes of MUFA rich diets, and to the low prevalence of
chronic disease in populations consuming MUFA rich Mediterranean diets, national dietary guidelines are increasingly recommending
dietary MUFA, primarily at the expense of saturated fatty acids (SFA). Consumption of dietary MUFA promotes healthy blood
lipid profiles, mediates blood pressure, improves insulin sensitivity and regulates glucose levels. Moreover, provocative
newer data suggest a role for preferential oxidation and metabolism of dietary MUFA, influencing body composition and ameliorating
the risk of obesity. Mounting epidemiological and human clinical trial data continue to demonstrate the cardioprotective activity
of the MUFA content of dietary fat. As the debate on the optimal fatty acid composition of the diet continues, the benefit
of increasing MUFA intakes, particularly as a substitute for dietary SFA, deserves considerable attention. 相似文献
22.
Developments in the continuous galvanizing of steel 总被引:1,自引:0,他引:1
The performance history of galvanized steels, particularly in the automotive industry, has heightened demand for both hot-dip galvanized and electrogalvanized products. Such marketability has led to the commissioning of several new galvanizing lines in recent years. Still, for this timehonored coating process to remain competitive, researchers are investigating methods to improve surface appearance, coating uniformity, corrosion resistance and cost effectiveness. 相似文献
23.
Steve Bush 《集成电路应用》2009,(8)
帝国理工学院(Imperial Collage)剥离出来的QuantaSol声称,他们已经打破了单结太阳能电池的世界记录。当曝露在500倍聚光的条件下,应力平衡的量子阱太阳能电池的转换效率记录为28.3%。 相似文献
24.
Proper configuration management is vital for host and network security. We outline the problems, especially for large-scale environments, and discuss the security aspects of a number of different configuration scenarios, including security appliances (e.g., firewalls), desktop and server computers, and PDAs. We conclude by discussing research challenges. 相似文献
25.
Steady-state and transient ampacity of bus bar 总被引:1,自引:0,他引:1
This paper presents a thermal model that can be used to calculate both the steady-state and transient electrical current carrying capacity (ampacity) of a power system busbar. Using a thermal model, a computer program has been formulated that can calculate the ampacity of busbar for any time-varying current and any variation in environmental conditions. Relations for the convection heat transfer coefficient for busbars with circular, rectangular and angular cross-sections are presented. The steady state values for ampacity predicted by the program are compared to accepted values. The transient capabilities of the program are illustrated by calculating the variation in busbar temperature when it is subjected to a step change in current. The predicted temperature histories of typical bus designs are compared to temperatures measured in the laboratory using thermocouples attached to the bus material 相似文献
26.
Abstract. In an increasingly dynamic business environment characterized by fast cycle times, shifting markets and unstable technology, a business organization’s survival hinges on its ability to align IT capabilities with business goals. To facilitate the successful introduction of new IT applications, issues of project risk must be addressed, and the expectations of multiple stakeholders must be managed appropriately. To the extent that users and developers may harbour different perceptions regarding project risk, areas of conflict may arise. By understanding the differences in how users and project managers perceive the risks, insights can be gained that may help to ensure the successful delivery of systems. Prior research has focused on the project manager’s perspective of IT project risk. This paper explores the issue of IT project risk from the user perspective and compares it with risk perceptions of project managers. A Delphi study reveals that these two stakeholder groups have different perceptions of risk factors. Through comparison with a previous study on project manager risk perceptions, zones of concordance and discordance that must be reconciled are identified. 相似文献
27.
Giuseppe Fregapane Douglas B. Sarney Sydney G. Greenberg Dorothy J. Knight Evgeny N. Vulfson 《Journal of the American Oil Chemists' Society》1994,71(1):87-91
5-O-Acyl-1,2-O-isopropylidene-D-xylofuranose and 6-O-acyl1,2∶3,4-di-O-isopropylidene-D-galactopyranose were enzymatically prepared from the corresponding monosaccharide acetals and commercial
(crude) fatty acid mixtures. Subsequent acid-catalyzed hydrolysis of the isopropylidene group(s) gave monosaccharide esters
with overall yields of 59–88%, where the monoester content was at least 80% (galactose oleate) and typically 90% for the other
preparations. In contrast to sugar fatty acid esters prepared by conventional, high-temperature (trans)esterification, the
enzymatically obtained monosaccharide esters contained no appreciable quantities of undersirable side products, and the only
contaminants were monosaccharides and fatty acids. 相似文献
28.
29.
A range of polymers carrying amino-functions [NHEt, NHBun, NEt2, NPr, N(CH2CH2CH2NH2)2, NMeCH2CH2CH2NH2 or NEtCH2CH2CH2 NH2] has been synthesised via amination of styrene-vinylbenzyl chloride copolymers, poly(epichlorohydrin) and poly(2-chloroethyl vinyl ether), and via homopolymerisation and copolymerisation (with styrene) of (n-butyl)(vinylbenzyl)-ammonium chloride. Some of the polymers showed promise as curing agents for epoxy resins. 相似文献
30.