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31.
Friesian cattle, aged 26-27 months, were fed a diet supplemented with 2000IU α-tocopheryl acetate/kg feed/day and another group was fed a basal diet (20IU/kg feed/day) for approximately 50 days prior to slaughter. Following frozen storage (-20°C for 8 weeks) semimembranosus muscles from basal and α-tocopheryl acetate supplemented cattle were minced and vacuum packaged, aerobically packaged or packaged under modified atmospheres (MAP) (30% O(2): 70% CO(2); 70% O(2): 30% CO(2); 80% O(2): 20% CO(2)). Samples were held under refrigerated (4°C) display (fluorescent lighting, 616 lux) for eight days. Vacuum-packaged samples were held under similar conditions but in complete darkness and allowed to bloom for a minimum of 4hr prior to taking colour readings. TBARS values and Hunter a values in minced beef were measured every two days. α-Tocopherol concentrations were significantly (p<0·05) higher in minced meat samples from the supplemented group than in the basal group. Significant (p<0·05) reductions in α-tocopherol concentrations in supplemented meat samples were observed with increased concentrations of oxygen in different packaging systems after eight days of refrigerated storage. TBARS values were reduced over the whole retail display period for all packaging systems when α-tocopheryl acetate supplemented beef was used. TBARS values increased as oxygen levels increased in MAP. Hunter a values showed that vitamin E supplementation in combination with vacuum packaging and MAP improved the colour stability of meat during the first 4 days of storage, however, the failure of MAP to extend meat colour for longer periods of time was probably the result of prior storage at -20°C for 8 weeks.  相似文献   
32.
Shawn Farkas 《硅谷》2005,(6):19-23
通过使用动态程序集加载和反射,托竹代码提供了通过外接程序轻松扩展直用程序的方法。但是,当允许应用程序通过外接程序模型运行任意代码时,就将用户计算机暴露在潜住的未知代码之下,有很大风险,恶意代码可能会使用您的应用程序作为进入用户数据的入口点。可以采用若干方法缩小应用程序的攻击面,防止恶意代码或不稳定代码破坏用户计算机——戒者防止敏感数据被窃取。  相似文献   
33.
The development of adipose tissue in the chick embryo was investigated using two groups of fertile eggs which differed by 1.7-fold in their initial yolk lipid levels. The triacylglycerol content of the subcutaneous adipose depot in both groups increased dramatically from day 12 of the 21-day embryonic period, attaining a maximal value just prior to hatching. During this period, the amount of triacylglycerol deposited in the adipose tissue was very highly correlated with the amount of lipid transferred from the yolk. The triacylglycerol content of the depot was also dependent on the initial yolk lipid content. During the hatching period, the amount of adipose triacylglycerol remained approximately constant in the group with the higher initial yolk lipid content but, in the case of the group with the lower initial yolk lipid levels, decreased by approximately 25%. The size distribution of adipocytes isolated from the tissue was determined by computerized image analysis microscopy. The mean adipocyte diameter increased from approximately 6 to 35 μm between days 12 and 19, irrespective of the initial yolk content, although development within the eggs with the lower initial yolk content resulted in a decrease in cell size over the hatching period. Both the triacylglycerol and phospholipid fractions of the isolated adipocytes contained substantial proportions (approximately 6%, w/w) of docosahexaenoic acid (DHA) at days 12 and 14, and lower levels of this fatty acid at the later stages. The amount (mg/depot) of DHA in adipose triacylglycerol decreased dramatically over the hatching period. The amount (mg/brain) of DHA in brain phospholipid increased by more than 5-fold between day 12 of development and hatching. A possible explanation for the data may be that DHA is preferentially mobilized from adipose tissue in order to deliver the fatty acid to the developing neural tissues in a form suitable for uptake.  相似文献   
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35.
I. Farkas  Z. Rendik 《Drying Technology》2013,31(6-8):1951-1960
ABSTRACT

In this study a block oriented modelling technique was introduced in order to simulate the intermittent drying technology process. First, the relevant blocks of the parameters concerning to drying air and the properties of material to be dried were developed. These blocks were then used to set up the full modell of a fix bed dryer including the temperature and moisture distribution of drying air and The material along the depth of the dryer. The simulation results were compared to Bakker-Arkema model with a good agreement. Finally, several measurements were performed for the case of thin layer of com to prove the advantage of the intermittent drying technology. It has been founded that in both energy saving and quality of dried product the intermittent technology has a significant contribution.  相似文献   
36.
CIE Division 1 entrusted TC 1–74 to investigate the possibility to develop a smooth curve version of the D illuminants. This article investigates the possibility to create such smoothed curves with minimal colorimetric error. Six different smoothing algorithms were investigated; the best method, using a locally weighted regression and smoothing algorithm, enabled a smooth function, where the worst colour difference for a 100 000 sample set was less than ΔEab* = 0.5, comparing calculations using the CIE standard daylight spectrum and the smoothed function. Thus, the smoothed function can be recommended for redefining the daylight spectra for colorimetry without loosing continuity to results using the current calculation tables and for designing daylight simulator spectra. © 2012 Wiley Periodicals, Inc. Col Res Appl, 38, 316–321, 2013  相似文献   
37.
Abstract

when the Sixth International Congress on Catalysis convend in London on July 12,1976, almost exactly 20 years had gone by since the first congress had met in Philadelphia. The elapsed two decades were golden years for catalysis science and technology. These disciplines, taking advantage of the advances in th chemistry and physics of surfaces and the solid state, in coorfinationchemistry, in metalorganies, in computer, chromatography, and other instrumental techniques, and profiting from the general scientific and technical eupnoria engendered by the spectacular exploits of space exploration, have progressed at a tremendous pace on a wice front. The Wacker process, ammondation, Nana-Ziegler catalysts, ceoilte, cracking, bimetallic reforming, wilkinson, chemistry, oxycnlorination, olerin disproportionation or matatnesis, polyrethane foams and elascomers, and catalytic mufflers are some of the key words that signify the revolutionary catalytic technologies developed during this period.  相似文献   
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39.
Resorcinol was acylated by phenylacetyl chloride with a set of catalysts consisting of the montmorillonite-based K-series and their cation-exchanged forms. The selectivity of C-acylation over O-acylation could be significantly increased by an appropriate ion exchange and by a solvent-free reaction mode, resulting in a 60% preparative yield of 1-(2,4-dihydroxyphenyl)-2-phenyl-ethanone. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
40.
Advances in genetics and genetic testing promise to catalyze a fundamental change in the practice of medicine. Psychologists have much to offer as psychotherapists, researchers, educators, and policymakers to a society heavily influenced by the genetic revolution. To make the most of new opportunities available to mental health professionals in genetics, psychologists must know basic genetic principles and learn what is new about 21st-century genetics. The core competencies for all health professionals developed by the National Coalition for Health Professional Education in Genetics are related in this article to the significant roles psychologists can play in helping individuals with genetic concerns to cope with vulnerability, optimize family interaction, and improve health behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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