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1.
Oxylipins are bioactive lipids formed by the monooxygenation of polyunsaturated fatty acids (PUFA). Eicosanoids derived from arachidonic acid (ARA) are the most well-studied class of oxylipins that influence brain functions in normal health and in disease. However, comprehensive profiling of brain oxylipins from other PUFA with differing functions, and the examination of the effects of dietary PUFA and sex differences in oxylipins are warranted. Therefore, female and male Sprague–Dawley rats were provided standard rodent diets that provided additional levels of the individual n-3 PUFA α-linolenic acid (ALA), eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA), or the n-6 PUFA linoleic acid (LNA) alone or with ALA (LNA + ALA) compared to essential fatty acid-sufficient control diets. Oxylipins and PUFA were quantified in whole brains using HPLC-MS/MS and GC, respectively. Eighty-seven oxylipins were present at quantifiable levels: 51% and 17% of these were derived from ARA and DHA, respectively. At the mass level, ARA and DHA oxylipins comprised 81–90% and 6–12% of total oxylipins, while phospholipid ARA and DHA represented 25–35% and 49–62% of PUFA mass, respectively. Increasing dietary n-3 PUFA resulted in higher levels of oxylipins derived from their precursor PUFA; otherwise, the brain oxylipin profile was largely resistant to modulation by diet. Approximately 25% of oxylipins were higher in males, and this was largely unaffected by diet, further revealing a tight regulation of brain oxylipin levels. These fundamental data on brain oxylipin composition, diet effects, and sex differences will help guide future studies examining the functions of oxylipins in the brain. 相似文献
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研究分析18个黍稷(Panicum miliaceum L.)品种的籽粒含油量和脂肪酸组成。结果表明,黍稷籽粒含油量为2.54%~4.00%,均值3.71%。黍稷籽粒中主要脂肪酸为亚油酸(18:2n6)、油酸(18:1n9)和棕榈酸(16:0),含量区间分别为0.075~5.19、0.150~3.02和0.897~1.81 g/100 g,并含有棕榈油酸、硬脂酸、亚麻酸、花生四烯酸、二十二烷酸和二十四烷酸。不饱和脂肪酸(UFA)占总油脂的82.1%~ 94.6%。相关性分析和主成分分析的结果表明,10种脂肪酸含量存在显著的相关性。聚类分析表明,脂肪酸组成在黍稷品种间的差异显著。 相似文献
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Mengting Ma Zijun Li Feng Yang Huaixiang Wu Wuyang Huang Zhongquan Sui Harold Corke 《International Journal of Food Science & Technology》2021,56(7):3607-3617
Waxy, normal and high-amylose maize starches were subjected to heat-moisture treatment (HMT) and then added to wheat flour (WF) in different ratios (1%, 5% and 10%). The properties of blends and their cooked noodles were studied to investigate the effects of HMT starches. The incorporation of HMT starch in WF led to an increase in swelling power, peak viscosity and breakdown and to a decrease in setback, thus inhibiting retrogradation, hence enhancing resultant noodle softness. Compared to the same addition ratio of native starch to WF, HMT starch led to higher tensile strength and extensibility in resultant noodles. WF with added HMT starch had higher resistant starch than with native starch. This study showed that addition of HMT maize starch has potential to bring nutritional benefits. However, it is necessary to select the proper blending ratio and amylose content of starch to add, in consideration of its effect on noodle quality. 相似文献
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Number entry is a ubiquitous activity and is often performed in safety- and mission-critical procedures, such as healthcare, science, finance, aviation and in many other areas. We show that Monte Carlo methods can quickly and easily compare the reliability of different number entry systems. A surprising finding is that many common, widely used systems are defective, and induce unnecessary human error. We show that Monte Carlo methods enable designers to explore the implications of normal and unexpected operator behaviour, and to design systems to be more resilient to use error. We demonstrate novel designs with improved resilience, implying that the common problems identified and the errors they induce are avoidable. 相似文献
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Harold Weiss 《EDPACS》2013,47(11):1-9
Abstract In spite of an ambiguous standard with regard to definition, spyware is one of the most challenging problems confronting the information technology (IT) community in terms of privacy violations. This problem is magnified in the business arena. Despite the increasing technical endeavors made toward spyware mitigation, no panacea exists for spyware control and management, which is now becoming a serious business strategic issue. This article focuses on the vicious side of spyware. A framework is proposed to identify five involved parties for spyware management and control along with respective recommendations to cope with spyware pervasion. 相似文献
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