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1.
The objectives of this study were to quantify the effectiveness of dietary retinol sources, orange fruit, and dark-green, leafy vegetables in improving vitamin A status, and to test whether orange fruit is a better source of vitamin A and carotenoids than are leafy vegetables. Anemic schoolchildren aged 7-11 y (n = 238) in West Java, Indonesia, were randomly allocated to 1 of 4 groups to consume 2 complete meals/d, 6 d/wk, for 9 wk: 1) 556 retinol equivalents (RE)/d from retinol-rich food (n = 48); 2) 509 RE/d from fruit (n = 49); 3) 684 RE/d from dark-green, leafy vegetables and carrots (n = 45); and 4) 44 RE/d from low-retinol, low-carotene food (n = 46). Mean changes in serum retinol concentrations of the retinol-rich, fruit, vegetable, and low-retinol, low-carotene groups were 0.23 (95% CI: 0.18, 0.28), 0.12 (0.06, 0.18), 0.07 (0.03,0.11), and 0.00 (-0.06, 0.05) micromol/L, respectively. Mean changes in serum beta-carotene concentrations in the vegetable and fruit groups were 0.14 (0.12, 0.17) and 0.52 (0.43, 0.60) micromol/L, respectively. Until now, it has been assumed that 6 microg dietary beta-carotene is equivalent to 1 RE. On the basis of this study, however, the equivalent of 1 RE would be 12 microg beta-carotene (95% CI: 6 microg, 29 microg) for fruit and 26 microg beta-carotene (95% CI: 13 microg, 76 microg) for leafy vegetables and carrots. Thus, the apparent mean vitamin A activity of carotenoids in fruit and in leafy vegetables and carrots was 50% (95% CI: 21%, 100%) and 23% (95% CI: 8%, 46%) of that assumed, respectively. This has important implications for choosing strategies for controlling vitamin A deficiency. Research should be directed toward ways of improving bioavailability and bioconversion of dietary carotenoids, focusing on factors such as intestinal parasites, absorption inhibitors, and food matrixes.  相似文献   
2.
The dependence of the color of a celadon glaze on the chemical composition and the electronic state of Fe was investigated by Mössbauer spectroscopic and chromaticity analysis. The amount of Fe2O3 was found to be the main factor influencing L* and b* values, whereas the amount of TiO2 was found to affect all the parameters (L*, a*, b*). The effect of MnO on the color was significant only by interaction terms. The amount of P2O5 was found to be the main factor of the b* value. According to the Mössbauer analysis results, as the amount of divalent iron ions increases, the a* and b* values decreased; on the other hand, the L* value increased. As the amount of titanium increased, Fe2+ was found to be destabilized relative to Fe3+ due to the structural instability of Fe-O-Ti network.  相似文献   
3.
Food-based approaches for controlling vitamin A deficiency and its consequences, such as increased mortality, more severe morbidity, and anemia, have become increasingly important, thus prompting a reassessment of the relation between vitamin A intake and status. A nutrition surveillance system in Central Java, Indonesia, assessed the vitamin A intake and serum retinol concentration of women with a child < or =24 mo old with a semiquantitative 24-h recall method that categorized vitamin A-containing foods into 3 categories of plant foods and into 2 categories of animal foods and identified portions as small, medium, or large. Median vitamin A intake was 335 retinol equivalents (RE)/d (n = 600) and vitamin A intake from plant foods was 8 times higher than from animal foods. Serum retinol concentration was related to vitamin A intake in a dose-response manner. The multiple logistic regression model for predicting the chance for a serum retinol concentration greater than the observed median (> or = 1.37 micromol/L) included physiologic factors, vitamin A intake from plant [odds ratio (95% CI) per quartile: 1st, 1.00: 2nd, 1.23 (0.75, 2.02); 3rd, 1.60 (0.97, 2.63); and 4th, 2.06 (1.25, 3.40)] and animal [1st and 2nd, 1.00; 3rd, 1.31 (0.86, 2.02); and 4th, 2.18 (1.40. 3.42)] foods, home gardening [(no, 1.00; yes, 1.71 (1.12, 2.60)], and woman's education level [< or =primary school, 1.00; > or =secondary school, 1.51 (1.02, 2.22)]. Despite the fact that plant foods contributed 8 times as much vitamin A as did animal foods, serum retinol concentrations did not reflect this large difference. Home gardening and woman's education level seemed to reflect longer-term consumption of vitamin A-rich plant and animal foods, respectively.  相似文献   
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5.
Triglycerides of mango seed kernel fat contain, depending on the variety, 32.4–44.0% of stearic acid and 43.7–54.5% of oleic acid. Palmitic and linoleic acids represent, respectively, 5.9–9.1% and 3.6–6.7% of the fatty acids. The triglycerides also contain minor amounts of arachidic and linolenic acids. Palmitic, stearic and arachidic acids were almost exclusively distributed among thesn-1-andsn-3-positions. Oleic acid represented 85–89% of the fatty acids at thesn-2-position. Oleic acid at thesn-1- andsn-3-positions showed a preference for thesn-1-position. Linoleic acid was mainly esterified at thesn-2-position. The amounts of saturated fatty acids, i.e., palmitic and stearic acids, and of oleic acid, at thesn-1- and sn-3-positions, were linearly related to their respective contents in the total triglycerides.  相似文献   
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7.
The distribution of fatty acids between the sn-1-, sn-2- and sn-3-positions of the triglycerides from the oils of eight African peanut varieties has been determined. The saturated fatty acids and eicosenoic acid occur almost exclusively at the sn-1- and sn-3-positions. The sn-1-position contained slightly more palmitic acid than the sn-3-position. The fatty acids with a chain length exceeding 18 carbons were preferentially incorporated in the sn-3-position. Linoleic acid was preferentially esterified at the sn-2-position, whereas oleic acid was equally distributed among the three positions. The amount of the saturated fatty acids, i.e., palmitic and stearic acid, and of oleic acid and linoleic acid incorporated in the sn-1-, sn-2-and sn-3-position, were each linearly related to their respective content in the triglycerides.  相似文献   
8.
The triglyceride composition of the kernel fat of 9 different mango varieties has been determined. Stearic and oleic acids represent respectively from 32.7 to 44.0% and from 43.7 to 53.4% of the total fatty acids. The remaining fatty acids were palmitic (6.7-9.7%), linoleic (3.6-6.9%), arachidic (1.1-2.5%) and linolenic (0.3–1.0%) acids. The triglyceride components were determined by separating the triglycerides according their degree of unsaturation by means of thin-layer chromatography on silica gel impregnated with silver nitrate. The fatty acid composition of the different triglyceride fractions and of the fatty acids incorporated at the sn-2-position of each triglyceride fraction was determined. Moreover, the triglycerides were separated according to their carbon number by gas liquid chromatography using an open-tubular glass column, wall-coated with CP-Sil 5. The triglyceride compositions obtained by thin-layer chromatography on silica gel impregnated with silver nitrate were in agreement with the compositions predicted by the 1,3-random-2-random distribution hypothesis.  相似文献   
9.
The crystalline phase of layered transition metal dichalcogenides (TMDs) directly determines their material property. The most thermodynamically stable phase structures in TMDs are the semiconducting 2H and metastable metallic 1T phases. To overcome the low phase purity and instability of 1T-TMDs, which limits the utilization of their intrinsic properties, various synthesis strategies for 1T-TMDs have been proposed in phase-engineering studies. Herein, a facile and scalable synthesis of 1T-phase molybdenum disulfide (MoS2) via the molten-metal-assisted intercalation (MMI) approach is introduced, which exploits the capillary action of molten potassium and the difference between the electron affinity of MoS2 and the ionization potential of potassium. Highly reactive molten potassium metal can readily intercalate into the MoS2 interlayers, inducing an efficient phase transition from the 2H to 1T crystal structure. The ionic bonding between the intercalated potassium and sulfur lowers the energy barrier of the 1T-phase transition, enhancing the phase stability of the 1T crystals. Owing to the high purity and stability of the 1T phase, the electrocatalytic performance for the hydrogen evolution reaction is significantly higher in 1T-MoS2 (MMI) than in 2H-MoS2 and even in 1T-MoS2 synthesized using n-butyllithium.  相似文献   
10.
Business process orientation (BPO) supports business process management by reorienting employees’ focus from functional performance to customer value adding. While it is generally believed that BPO improves various aspects of organizational performance, there has been a lack of empirical evidence. The results of this study showed that BPO significantly influences organizational innovation performance and identified the underlying mechanism for the effect. Interestingly, it is found that a process view is not sufficient to enhance organizational innovation performance. Cross-functional integration may also need to be carefully managed for innovation. These findings improve the current understanding of BPO and offer managerial suggestions for enhancing innovation.  相似文献   
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