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1.
An inulin syrup made from Jerusalem artichoke tubers, either in its commercial form or after ultrafiltration, was freeze-dried and used as a prebiotic ingredient in the small-scale manufacture of wafer crackers. The flours used for the preparation of wafer batters were from wheat, rye or spelt wheat, or 1:1 combinations of wheat flour and rye flour or wheat flour and spelt wheat flour. Batter viscosity was strongly influenced by the selection of the flour type, but remained within technologically acceptable limits. The ultrafiltration of the inulin syrup, using a 1 kDa membrane, resulted in a significant reduction of the content of free sugars and minerals which, in turn, had a significant impact on the CIE-Lab color values of the wafer crackers. Using spelt wheat flour instead of wheat flour significantly increased wafer cracker firmness measured by penetration, as did the incorporation of ultrafiltered freeze-dried instead of native freeze-dried Jerusalem artichoke syrup. Sensory analysis revealed a significant influence of product formulation on appearance, flavor and texture of the wafer crackers. It can be concluded from quality scores, which were calculated by using weighting factors assigned to the sensory attributes, that wheat flour may be partially replaced by rye flour or spelt wheat flour without negatively affecting the sensory properties of the wafer crackers. 相似文献
2.
Recent advances in the biosynthesis of fatty acids by maturing safflower seeds are described. We now can define the systems
responsible for (a) the conversion of CO2 to sucrose to acetyl CoA; (b) the condensation of acetyl CoA via the de novo acyl carrier protein pathway to the terminal
product, palmityl acyl carrier protein; (c) the elongation of palmityl acyl carrier protein to stearyl acyl carrier protein
by a specific malonyl acyl carrier proteinelongation system; (d) the desaturation of stearyl acyl carrier protein to oleic
acid by a highly specific, soluble stearyl acyl carrier protein desaturase; (e) the further desaturation of oleyl CoA to linoleyl
CoA; and (f) the transfer of acyl CoAs to glycerol-3-phosphate to the final product, a triacylglycerol and its coalescence
to the typical high lipid containing mature seed, engorged with oil droplets.
Future research should be directed to a fuller understanding of how the maturing seed triggers these complicated series of
reactions, how all these enzymes are coordinated to allow a smooth flow of substrates for the formation of oil droplets, and,
finally, how biochemical engineering can further improve oil crops in the ever growing demand for high yielding systems.
Winner of the Award in Lipid Chemistry presented at the 48th Annual Fall Meeting, September, 1974, Philadelphia. 相似文献
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Virtual environments have become a key component of many fields and the critical component of virtual reality applications. Due to their virtual nature, they can accommodate an infinite number of possibilities. A theoretical work is presented, which decomposes those innumerous possibilities into concepts to help clarify the vast design space and provide insights into future applied research. We propose that what makes environments interesting and engaging is having worlds that are both active and reactive. This article explores the manifestations of those actions and reactions in what we term: dynamic components and interactions. We term worlds containing these dynamic interactive virtual environments (DIVE). An analysis of each component time was performed, with the purpose of providing a theoretical understanding of the respective design spaces. Initially, we collected the myriad possibilities of each component, e.g., the possible kinds of interactions. We point to examples throughout the field to ground and explain concepts presented. We then categorized of each area into taxonomies. The result of the analyses provides insights into the design space of virtual environments, exposes several avenues of research that are yet underexplored, and provides better understandings of ways in which DIVE creation can be supported. 相似文献
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Gabriel Reboux Steffi Rocchi Audrey Laboissire Habiba Ammari Martine Bochaton Guillaume Gardin Jean‐Marc Rame Laurence Millon 《Indoor air》2019,29(1):5-16
Different countries have tried to define guidelines to quantify what levels of fungi are considered as inappropriate for housing. This retrospective study analyzes indoor fungi by cultures of airborne samples from 1012 dwellings. Altogether, 908 patients suffering from rhinitis, conjunctivitis, and asthma were compared to 104 controls free of allergies. Portuguese decree law no 118/2013 (PDL118), ANSES (a French environmental and health agency) recommendations, and health regulations of Besançon University Hospital were applied to determine the rates of non‐conforming dwellings, which were respectively 55.2%, 5.2%, and 19%. Environmental microbiological results and medical data were compared. The whole number of colonies per cubic meter of air was correlated with asthma (P < 0.001) and rhinitis (P = 0.002). Sixty‐seven genera and species were detected in bedrooms. Asthma was correlated to Aspergillus versicolor (P = 0.004) and Cladosporium spp. (P = 0.02). Thresholds of 300 cfu/m3 for A. versicolor or 495 cfu/m3 for Cladosporium spp. are able to discriminate 90% of the asthmatic dwellings. We propose a new protocol to obtain an optimal cost for indoor fungi surveys, excluding surface analyses, and a new guideline to interpret the results based on >1000 cfu/m3 of whole colonies and/or above threshold levels for A. versicolor or Cladosporium spp. 相似文献
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Acyl-CoA: alcohol transacylase activity was demonstrated in cell-free homogenates of developing jojoba seeds. The optimal
pH was 8.0–8.1. Under optimal conditions, wax formation had a nearly linear relationship with extract concentration; the time
course of wax formation was also linear up to 30 min.cis-11-Eicosenol was the most effective alcohol substrate whereas tetradecanol, octadecanol, dodecanol,cis-9-octadecanol, andcis-13-eicosenol gave progressively lower activities. Either saturated or unsaturated acyl-CoA with 18 or 20 C-atoms had similar
activity. The enzyme was fairly stable at 0 C, less stable at RT and labile above 30 C. Differential centrifugation showed
that the 12,000 × g fat pad was the most active in wax formation; to maximize the activity, a 12,000 × g supernatant appeared
to be necessary. This factor in the supermatant was thermolabile and nondialyzable. 相似文献
10.
Philp E Sloan J Kirkland AI Meyer RR Friedrichs S Hutchison JL Green ML 《Nature materials》2003,2(12):788-791
Single-walled carbon nanotubes (SWNTs) can be used as templates for the growth of low-dimensional inorganic materials whose structures and properties often differ greatly from those of the bulk. Here we describe the detailed crystallography of an entire helical one-dimensional cobalt diiodide nanostructure encapsulated within a SWNT. This material has an unprecedented twisted double tetrahedral chain structure arising from a rotation of Co(2)I(4) units along its length. The complete nanostructure comprises two distinct regions with oppositely handed helices separated by a short disordered region. The encapsulating SWNT shows a commensurate ovoid distortion reflecting an unexpectedly strong interaction between the nanostructure and the SWNT. 相似文献