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101.
We consider the application of the Schreier-Sims algorithm and its variations to matrix groups defined over finite fields. We propose a new algorithm for the selection of the base points and demonstrate that it both improves the performance of the algorithm for a large range of examples and significantly extends the range of application. In particular, the random Schreier-Sims algorithm, with this enhancement, performs extremely well for almost simple groups. 相似文献
102.
J L Vicini W S Cohick J H Clark S N McCutcheon D E Bauman 《Journal of dairy science》1988,71(5):1232-1238
Eight Holstein cows were used to investigate the effects of DM intake and sodium bicarbonate on lactational performance and concentrations of hormones and metabolites in plasma. Cows were fed a diet with or without 1.0% sodium bicarbonate (dry matter basis) in a switchback design. Four cows were fed ad libitum and four cows were fed approximately 80% of their recommended nutrient requirements by restriction of DM intake throughout the three 21-d periods. Supplementing the diet with sodium bicarbonate increased DM intake of cows fed ad libitum. There was a feed intake by sodium bicarbonate interaction for production of 4% FCM. This interaction may be explained by the difference in DM intake of cows fed ad libitum or restricted amounts of feed and supplemented with sodium bicarbonate. Cows fed restricted amounts of feed had lower milk, milk fat, milk protein, milk SNF, and milk energy yields. Restriction of feed intake increased plasma concentrations of somatotropin and nonesterified fatty acids but decreased concentrations of insulin, triidothyronine, thyroxine, glucagon, and prolactin. In contrast, feeding supplemental sodium bicarbonate did not affect concentrations of hormones or metabolites in plasma at either feed intake. 相似文献
103.
Satisfying America's Fruit Gap: Summary of an Expert Roundtable on the Role of 100% Fruit Juice
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Carol Byrd‐Bredbenner Mario G. Ferruzzi Victor L. Fulgoni III Robert Murray Elizabeth Pivonka Taylor C. Wallace 《Journal of food science》2017,82(7):1523-1534
The 2015 to 2020 Dietary Guidelines for Americans (DGAs) recognize the role of 100% fruit juice in health and in helping people meet daily fruit recommendations and state that 100% fruit juice is a nutrient‐dense beverage that should be a primary choice, along with water and low‐fat/fat‐free milk. The DGAs note that children are consuming 100% fruit juice within recommendations (that is, 120 to 180 mL/d for children aged 1 to 6 y and 236 to 355 mL/d for children aged 7 to 18 y). Evidence shows that compared to nonconsumers, those who consume 100% fruit juice come closer to meeting daily fruit needs and have better diet quality. In children, 100% fruit juice is associated with increased intakes of nutrients such as vitamin C, folate, and potassium. When consumed within the DGA recommendations, 100% fruit juice is not associated with overweight/obesity or childhood dental caries and does not compromise fiber intake. Preliminary data suggest that polyphenols in some 100% fruit juices may inhibit absorption of naturally occurring sugars. Given its role in promoting health and in helping people meet fruit needs, experts participating in a roundtable discussion agreed that there is no science‐based reason to restrict access to 100% fruit juice in public health nutrition policy and programs such as the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Reducing or eliminating 100% fruit juice could lead to unintended consequences such as reduced daily fruit intake and increased consumption of less nutritious beverages (for example, sugar‐sweetened beverages). 相似文献
104.
Nordstrom JL Rangdale R Vickery MC Phillips AM Murray SL Wagley S DePaola A 《Journal of food protection》2006,69(11):2770-2772
Reliable methods are needed to detect total and pathogenic Vibrio parahaemolyticus. One marker of V. parahaemolyticus virulence is the thermostable-related hemolysin. We developed an alkaline phosphatase-labeled DNA probe method for the specific detection and enumeration of trh-positive V. parahaemolyticus by colony hybridization. The probe was tested against a panel of 200 bacterial strains and determined to be specific for trh-positive V. parahaemolyticus. Additionally, the trh alkaline phosphatase probe colony hybridization was successfully used to detect and enumerate trh-positive V. parahaemolyticus in seafood and water samples collected from the United States and the United Kingdom. 相似文献
105.
Marshall B. Elam Matthew A. von Wronski Lauren Cagen Fayanne Thorngate Poonam Kumar Murray Heimberg Henry G. Wilcox 《Lipids》1999,34(8):809-816
We previously demonstrated increased apolipoprotein B (apoB) mRNA editing, elevated levels of mRNA for the catalytic component
of the apoB mRNA editing complex, apobec-1, and increased secretion of the product of the edited mRNA, apoB48, in very low
density lipoproteins (VLDL) in primary cultures of Sprague-Dawley rat hepatocytes following insulin treatment. In order to
determine the effect of in vivo hyperinsulinemia on these processes, we determined apoB mRNA editing, apobec-1 expression, hepatic expression of mRNA for
apoB and other VLDL apoproteins, and the quantity and composition of plasma VLDL in the hyperinsulinemic fatty Zucker rat.
Total apoB mRNA content of the livers of the fatty rats and lean littermates did not differ, however, edited apoB message
coding for hepatic apo B48, and abundance of mRNA for the catalytic subunit of the apoB mRNA editing complex, apobec-1, was
increased by 1.7-and 3.3-fold, respectively, in fatty rats. ApoCIII mRNA abundance was increased in livers of fatty rats as
well, but the abundance of hepatic apoE mRNA in the fatty animal was not different from that of the lean rat. Hepatic apoAI
mRNA abundance was also increased in the fatty rats. Associated with increased apoB mRNA editing, was the 1.7-fold increase
in the fraction of apoB in plasma as apoB48 in fatty rats. VLDL-triglyceride and-apoB in plasma were 15-and 3-fold higher,
respectively, in fatty Zucker rats compared to lean littermates, indicating both enrichment of VLDL with triglycerides and
increased accumulation of VLDL particles. Increased hepatic expression of mRNA for apoCIII and apoAI was associated with increased
content of apoC (and relative depletion of apoE) in VLDL of fatty rats, and plasma apoAI was increased in fatty Zucker rats,
primarily in the HDL fraction. The current study provides further evidence that chronic exposure to high levels of insulin
influences both the quantity of and lipid/apoprotein composition of VLDL in plasma. The increased apoC and decreased apoE
(as well as increased triglyceride) content of VLDL in the fatty Zucker rat observed in the current study may affect VLDL
clearance and therefore may be a factor in the observed accumulation of VLDL in the plasma of the fatty hyperinsulinemic Zucker
rats. 相似文献
106.
This article reviews Computer Mediated Communications (CMC), encompassing the technology and its evaluation, with emphasis on factors crucial to the introduction of this technology in developing countries. The discussion of some promising application areas for developing countries includes education, networks of specialists, international committees and trade groups, and crisis detection and management. Also included is a summary of factors important to fostering and evolving the utilization of CMC technology. 相似文献
107.
108.
复合刚度方法是一种可以预测Z型截面构件支撑的屋面系统侧向受力的方法。该方法将一系列Z型截面作为单自由度系统分析,并采用刚度公式计算系统中不同的构件对于抵抗侧向位移的贡献。从力学理论中推导出屋面系统所需的抗力。 相似文献
109.
An empirically valid outcome in psychology may differ in the degree to which the outcome does or does not conform to human intuition. The author provides a brief history of three psychological outcomes violating human intuition, notes the resemblance to the common sense revolution, and then discusses how human intuition may be detrimental to behaviorism and evolutionary perspectives of human nature. The role of human intuition in supernatural beliefs is considered and, finally, possible methods to improve the plausibility of counterintuitive outcomes are suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
Murray MacKay 《The International journal of environmental studies》2013,70(1-4):223-227
Accidental trauma in general and traffic accidents in particular are discussed briefly within the framework of the host, agent, environment complex of conventional epidemiology. The rise of accidents is contrasted to the fall in infectious disease over the years, and then some of the basic characteristics of traffic accidents are reviewed. It is suggested that programmes which aim at behavioural modification are unlikely to produce startling improvements in the short run. Similarly the economic restrictions on environmental changes would seem to inhibit radical benefits from being achieved in the immediate future. The possibilities of injury reduction rather than crash avoidance are then discussed, and improvements in this area are suggested as having the greatest effect within the next few years. The emerging science of accident research is mentioned as an appropriate and distinctive field of study which should be encouraged. 相似文献