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41.
Andrea Felgner Regina Schlink Peter Kirschenbühler Birgit Faas Heinz-Dieter Isengard 《Food chemistry》2008
In the field of food analysis, rapid measurements and results are generally of high importance. The Karl Fischer titration (KFT), a chemical method for determining water content, and its automated performance enhance rapidity by giving the opportunity to deal with more samples in less time; automated sequences can include different determination methods and sample treatments. Moreover, automation can improve reproducibility and precision. 相似文献
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Wendy Hollands Gary M. Brett Pauline Radreau Shikha Saha Birgit Teucher Richard N. Bennett Paul A. Kroon 《Food chemistry》2008
Blackcurrant (BC) fruits are a rich source of biologically active anthocyanins but little is known of the anthocyanin content of commonly consumed BC products or how processing affects the absorption. We report that whereas fresh and frozen whole BC were a rich source of anthocyanins, containing 897 and 642 mg (100 g FW)−1 of total anthocyanins the levels in all other products were substantially lower (0.05–10.3% of the levels in fresh fruit). Further, when the absorption and excretion of BC was assessed in volunteers consuming a portion (100 g) of frozen whole BC (642 mg total anthocyanins) and, 300 g of a BC drink made by diluting concentrated syrup (33.6 mg total anthocyanins), only small quantities of BC anthocyanins were excreted in urine (fruit, 0.053 ± 0.022%; drink, 0.036 ± 0.043%; mean percent urinary yield ± SD) and they were not detected in plasma. These data indicate that fresh and frozen BC, but not processed products, are rich sources of anthocyanins but, regardless of the food source, these anthocyanins are poorly bioavailable. 相似文献
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Laurent Georges Matthias Haase Aoife Houlihan Wiberg Torhildur Kristjansdottir Birgit Risholt 《Building Research & Information》2015,43(1):82-93
The net-zero emissions building (nZEB) performance is investigated for building operation (EO) and embodied emissions in materials (EE) for Norway's cold climate. nZEB concepts for new residential and office buildings are conceived in order to understand the balance and implications between operational and embodied emissions over the building's life. The main drivers for the CO2 equivalent (CO2e) emissions are revealed for both building concepts through a detailed emissions calculation. The influence of the CO2e factor for electricity is emphasized and it is shown to have significant impact on the temporal evolution of the overall CO2e emissions balance. The results show that the criterion for zero emissions in operation is easily reached for both nZEB concepts (independent of the CO2e factor considered). Embodied emissions are significant compared to operational emissions. It was found that an overall emissions balance including both operational and embodied energy is difficult to reach and would be unobtainable in a scenario of low carbon electricity from the grid. In this particular scenario, the net balance of emissions alone is nonetheless not a sufficient performance indicator for nZEB. 相似文献
49.
Alexander Semmler Susanna Moskau Andreas Grigull Susan Farmand Thomas Klockgether Yvo Smulders Henk Blom Bernd Zur Birgit Stoffel-Wagner Michael Linnebank 《Nutrition journal》2010,9(1):1-4
Background
Several studies demonstrated an association of homocysteine plasma levels and the plasma lipoprotein profile. This cross-sectional pilot study aimed at analyzing whether blood levels of the two important cofactors of homocysteine metabolism, folate and vitamin B12, coincide with the lipoprotein profile.Methods
In a retrospective single center approach, we analyzed the laboratory database (2003-2006) of the University Hospital Bonn, Germany, including 1743 individuals, in whom vitamin B12, folate and at least one lipoprotein parameter had been determined by linear multilogistic regression.Results
Higher folate serum levels were associated with lower serum levels of low density lipoprotein cholesterol (LDL-C; Beta = -0.164; p < 0.001), higher levels of high density lipoprotein cholesterol (HDL-C; Beta = 0.094; p = 0.021 for trend) and a lower LDL-C-C/HDL-C-ratio (Beta = -0.210; p < 0.001). Using ANOVA, we additionally compared the individuals of the highest with those of the lowest quartile of folate. Individuals of the highest folate quartile had higher levels of HDL-C (1.42 ± 0.44 mmol/l vs. 1.26 ± 0.47 mmol/l; p = 0.005), lower levels of LDL-C (3.21 ± 1.04 mmol/l vs. 3.67 ± 1.10 mmol/l; p = 0.001) and a lower LDL-C/HDL-C- ratio (2.47 ± 1.18 vs. 3.77 ± 5.29; p = 0.002). Vitamin B12 was not associated with the lipoprotein profile.Conclusion
In our study sample, high folate levels were associated with a favorable lipoprotein profile. A reconfirmation of these results in a different study population with a well defined status of health, diet and medication is warranted. 相似文献50.
Birgit Palm Jürgen G. Heinrich Joachim Reuer 《International Journal of Applied Ceramic Technology》2010,7(2):226-234
The essential influences of 15 parameters on defects (cracks and bubbles) during production of tableware have been studied with 16 experimental progressions using a L16(215) experimental design by G. Taguchi. Evaluation (analysis of means and analysis of variance) indicated that in this production liter weight, drying time, moisture before biscuit firing, and position in the biscuit-firing kiln have a significant influence on cracks. Concerning bubbles, parameters with an influence are liter weight, gate system, mold material, and moisture content before glost firing. Rejects of the article used in the experiments were reduced from 2.44% to 2.27% with respect to cracks and from 6.22% to 0% with respect to bubbles. 相似文献