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OBJECTIVE: To assess the validity and reliability of the most recent adaptation of Block's full-diet food-frequency questionnaire (FFQ) among a sample of Canadian women. DESIGN: Participants completed a self-administered FFQ (FFQ1), two unannounced 24-hour recalls (weekday and weekend) and a second FFQ (FFQ2) between October 2003 and February 2004. FFQs and recalls were analysed for 32 nutrients using Block Dietary Data Systems and the University of Minnesota's Nutrient Data System. Mean and median intakes were computed, along with crude and deattenuated Pearson correlation coefficients between FFQ1 and the average of two recalls (validity) and between FFQ1 and FFQ2 (reliability). SETTING: Ontario, Canada. SUBJECTS: A random population-based sample (n = 166) of women aged 25 to 74 years. RESULTS: One hundred and fifteen (69%) women completed FFQ1, 96 completed FFQ1 and both recalls, and 93 completed both FFQs, about 56 days apart. Mean intakes were similar for most nutrients. FFQ reliability was high, with Pearson correlation coefficients having a median of 0.75, ranging from 0.57 to 0.90 (macronutrients) and from 0.65 to 0.88 (micronutrients from supplements and food). FFQ validity was moderate to high, with deattenuated Pearson correlation coefficients having a median of 0.59, ranging from 0.11 to 0.73 (macronutrients) and from 0.50 to 0.76 (micronutrients from supplements and food). Our micronutrient correlations were similar to or higher than those of other studies that included supplements. Two correlations <0.40 were associated with fats. CONCLUSIONS: The validity and reliability of this full-diet version of the Block FFQ were moderate to high, supporting its use in future studies among Canadian women.  相似文献   
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OBJECTIVE: The purpose of the present study was to characterise the food landscape of an inner city African American neighbourhood and its mixed-race suburban neighbour. Detailed analysis focuses on the relationship between community store mix and price, availability and produce quality. DESIGN: A market basket study was completed by members of the Chicago Food Systems Collaborative. The US Department of Agriculture's standard market basket survey and methodology were used. Additional items and analyses were added in consultation with community members. SETTING: Austin is a lower-middle-class African American community of 117,500 on the western edge of Chicago. Oak Park, which borders Austin, is an upper-middle-income suburb of 52,500 with a mixed racial profile.Subjects: A market basket survey of every retail food store in Austin and Oak Park was completed. A total of 134 were included. RESULTS: Results indicate that Austin has many grocery stores and few supermarkets. Many Austin groceries stores carry produce that is usually competitively priced, but often of unacceptable quality. Supermarkets had the best selection. Prices were lowest at discount supermarkets. Prices of packaged items were higher at independent stores than at chain supermarkets, but fresh items were cheaper. CONCLUSIONS: Food access is related more to store type than number. In this study, item availability and produce quality varied greatly between store types. Price differences were complicated and varied by store type and food category. This has consequences in terms of food purchasing decisions and dietary quality that public health professionals should acknowledge.  相似文献   
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Quantum-mechanical shell effects are expected to strongly enhance nuclear binding on an "island of stability" of superheavy elements. The predicted center at proton number Z = 114, 120, or 126 and neutron number N = 184 has been substantiated by the recent synthesis of new elements up to Z = 118. However, the location of the center and the extension of the island of stability remain vague. High-precision mass spectrometry allows the direct measurement of nuclear binding energies and thus the determination of the strength of shell effects. Here, we present such measurements for nobelium and lawrencium isotopes, which also pin down the deformed shell gap at N = 152.  相似文献   
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The pecan nut [Carya illinoinensis (Wangenh) C. Koch] is a natural source of polyphenols with antioxidant properties. In this study, the encapsulation of aqueous and hydroalcoholic extracts of pecan nut shell were evaluated for the release of bioactive compounds and antioxidant potential in order to explore food applications using zein as encapsulating agent. The extracts showed high contents of total phenolics, condensed tannins and high antioxidant activity. Concentrations of proanthocyanidins were 9-fold higher in hydroalcoholic extracts. The LC-DAD analysis showed that catechins were the major phenolic compounds in samples, with epigallocatechin levels up to 138.62 mg mL?1. Zein microparticles loaded with aqueous extract released 2.3 times more phenolic compounds than the hydroalcoholic extracts and the DSC thermograms showed that extracts of pecan nut shell remained thermally stable up to 240 °C. The zein microcapsules obtained in this study were efficiently encapsulated and represent an interesting additive due its high antioxidant capacity, physicochemical characteristics and morphology. The use of zein microparticles combined with natural extracts constitute a step forward in the improvement of current technology for delivering phenolic compounds with applications in functional foods and nutraceuticals.  相似文献   
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One of the most attractive aspects of food and agricultural studies for scholars is the level of public interest in the subjects of our research. Such interest means that food and agriculture scholars often become public scholars, asked to comment on issues of great interest to the public. In addition, food and agriculture scholars often have the opportunity to partner more directly with community organizations to perform community-based research. Such studies take many forms, but community members often take a lead role, helping plan the study as well as participate in data collection and analysis. Community based research may be very rewarding, but scholars involved in such research need to deal with a lack of control that inevitably goes along with it. This article gives examples of such research and discusses the public role of food and agriculture studies in general, in particular highlighting what can be learned from public responses to a 2009 shortage of Eggo waffles.  相似文献   
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In digestion trials using pigs fitted with ileo-rectal anastomoses and parallel intact pigs the influence of wheat straw meal (WSM) or grass meal (GM) supplemented on two different levels to a basal diet was examined with regard to nutrient and amino acid digestibility resp. absorption. Both roughages reduced, obviously because of their high cell wall contents, nearly at equal amounts and partly significantly the precaecal as well as the total digestibility of dry matter, organic matter, carbohydrates (= crude fibre + NFE), crude fibre and hemicelluloses (arabinose, xylose). By the roughage supplementations the crude protein digestibility at the terminal ileum was less reduced than at the end of the total digestive tract, the starch digestibility was hardly influenced and that of ether extract mostly increased. In comparison with precaecal glucose and fructose digestibilities it could be shown that the anthrone method is not suitable for determinations of the precaecal digestibility of water soluble carbohydrates. Beside these compounds other substances in the ileum digesta must evidently be dyed by anthrone too. The crude protein digestibility and the amino acid absorption were precaecally hardly or not reduced by WSM supplementations, therefore it can be concluded that it is possible to dilute the energy concentration in diets (e.g. for sows) by addition of WSM without impairing protein digestion and amino acid absorption. The GM supplementations, however, impaired protein digestibility and amino acid absorption of the whole diet, probably caused by the encrusted, possibly heat damaged protein present in the GM itself. When the roughage supplemented diets were fed, the excretion of nitrogen compounds in the faeces was enlarged due to the more intensive bacterial activity in the hind gut and the additional sorption effects to cell wall substances, so that a too low apparent and also true digestibility is made believe. The applicability of the difference method to the calculation of protein and amino acid digestibilities in roughages is very questionable because of their low contents and the missing additivity. The crude fibre and hemicellulose digestibility values calculated by the difference method demonstrate for the both roughages--in spite of high standard deviations--that the precaecal digestibility of crude fibre is about zero and that of the hard lignified hemicellulose fraction in contrast to the predominantly endospermic hemicelluloses of the basal diet is very low. The faecal crude fibre and hemicellulose digestibilities of WSM--especially on the lower supplementation levels--are markedly worse than those of GM.  相似文献   
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