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The present research contrasted theoretical models depicting the nature of the relation among drinking beliefs, drinking tendencies, and behavioral consequences in 266 incoming freshman college students. It also examined the theoretical relations between mother–teen communications and drinking beliefs relevant to behavioral consequences. The findings revealed direct relations between binge-drinking consequences and the drinking beliefs: Alcohol can make positive transformations, can enhance social behavior, and can increase negative affect and normative approval. Direct relations were not observed between consequences and the drinking beliefs regarding physical risk and health orientation. Finally, the present research found consistent support for the relation between mother–teen communications and drinking beliefs relevant to binge-drinking consequences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
Rob Bailis 《Biomass & bioenergy》2009,33(11):1491-1502
Current carbon accounting methodologies do not accommodate activities that involve emissions reductions from both land-use change and energy production. This paper analyzes the climate change mitigation potential of charcoal production in East Africa by examining the impact of changing both land management and technology. Current production in a major charcoal producing region of Kenya where charcoal is made as a by-product of land clearance for commercial grain production is modeled as the “business-as-usual” scenario. Alternative production systems are proposed based on coppice management of native or exotic trees. Improved kilns are also considered. Changes in aboveground, belowground, and soil carbon are modeled and two distinct baseline assessments are analyzed: one is based on a fixed area of land and one is based on the quantity of non-renewable fuel that is displaced by project activities. The magnitude of carbon emissions reductions varies depending on land management as well as the choice of carbonization technology. However, these variations are smaller than the variations arising from the choice of baseline methodology. The fixed-land baseline yields annualized carbon emission reductions equivalent to 0.5–2.8 tons per year (t y?1) with no change in production technology and 0.7–3.5 t y?1 with improved kilns. In contrast, the baseline defined by the quantity of displaced non-renewable fuel is 2–6 times larger, yielding carbon emissions reductions of 1.4–12.9 t y?1 with no change in production technology and 3.2–20.4 t y?1 with improved kilns. The results demonstrate the choice of baseline, often a political rather than scientific decision, is critical in assessing carbon emissions reductions. 相似文献
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An anionic surface‐active agent derived from wool proteins was developed as an alternative to the anionic surfactants extensively used in shampoo formulations. The physicochemical properties of this new surface‐active agent prepared form wool proteins and its application for human hair treatments were studied. This new product could be considered a new mild anionic surface‐active agent, as evidenced by the results found by the evaluation of its physicochemical properties. The new wool anionic surface‐active agent was shown to be very substantive to hair, coating the fiber surface, giving rise to a significant improvement in the mechanical properties of the hair fibers, and providing a certain damage‐prevention effect on the hair. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
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Núria Parera Pera Dr. Hilbert M. Branderhorst Dr. Raymond Kooij Caroline Maierhofer Dr. Marjolein van der Kaaden Rob M. J. Liskamp Prof. Dr. Valentin Wittmann Prof. Dr. Rob Ruijtenbeek Dr. Roland J. Pieters Dr. 《Chembiochem : a European journal of chemical biology》2010,11(13):1896-1904
Multivalency is an important phenomenon in protein–carbohydrate interactions. In order to evaluate glycodendrimers as multivalent inhibitors of carbohydrate binding proteins, we displayed them on a microarray surface. Valencies were varied from 1 to 8, and corrections were made for the valencies so that all surfaces contained the same amount of the sugar ligand. Five different carbohydrates were attached to the dendrimers. A series of fluorescent lectins was evaluated, and for each of them a binding profile was obtained from a single experiment showing both the specificity of the lectin for a certain sugar and whether it prefers multivalent ligands or not. Very distinct binding patterns were seen for the various lectins. The results were rationalized with respect to the interbinding distances of the lectins. 相似文献
89.
Dihal AA Tilburgs C van Erk MJ Rietjens IM Woutersen RA Stierum RH 《Molecular nutrition & food research》2007,51(8):1031-1045
The aim was to investigate mechanisms contributing to quercetin's previously described effects on cell-proliferation and -differentiation, which contradicted its proposed anticarcinogenic potency. In a 10-day experiment, 40 microM quercetin stabilized by 1 mM ascorbate reduced Caco-2 differentiation up to 50% (p < 0.001). Caco-2 RNA from days 5 and 10, hybridized on HG-U133A2.0 Affymetrix GeneChips(R), showed 1,743 affected genes on both days (p < 0.01). All 14 Caco-2 differentiation-associated genes showed decreased expression (p < 0.01), including intestinal alkaline phosphatase, that was confirmed technically (qRT-PCR) and functionally (enzyme-activity). The 1,743 genes contributed to 27 pathways (p < 0.05) categorized under six gene ontology (GO) processes, including apoptosis and cell-cycle. Genes within these GO-processes showed fold changes that suggest increased cell-survival and -proliferation. Furthermore, quercetin down-regulated expression of genes involved in tumor-suppression and phase II metabolism, and up-regulated oncogenes. Gene expression changes mediated by ascorbate-stabilized quercetin were concordant with those occurring in human colorectal carcinogenesis ( approximately 80-90%), but were opposite to those previously described for Caco-2 cells exposed to quercetin without ascorbate ( approximately 75-90%). In conclusion, gene expression among Caco-2 cells exposed to ascorbate-stabilized quercetin showed mechanisms contrary to what is expected for a cancer-preventive agent. Whether this unexpected in vitro effect is relevant in vivo, remains to be elucidated. 相似文献
90.
Yves Nicolas Marcel Paques Dirk van den Ende Jan K. G. Dhont Rob C. van Polanen Alexandra Knaebel Alain Steyer Jean-Pierre Munch Theo B. J. Blijdenstein George A. van Aken 《Food Hydrocolloids》2003,17(6):907
Three configurations have been developed to improve the understanding of structural element interactions in food material during deformation. The three configurations combine an inverted confocal scanning laser microscope (CSLM) and a cell that can apply to the sample a specific deformation: continuous shear, linear oscillatory shear and biaxial extension (compression).In the continuous shear and oscillatory shear configurations (OSCs), a zero-velocity plane is created in the sample by moving two plates in opposite direction, maintaining stable observation conditions of the structural behaviour under deformation. The OSC allows simultaneous application of CSLM and diffusing wave spectroscopy, a multiple light scattering technique. The third configuration (compression configuration) allows observation at a stagnation point during rheometric measurements. The configurations accept semi-liquid products (dressing, sauces, dairy products, etc.) for investigations in area such as aggregation, gelation, interactions at interface, coalescence, break-up. 相似文献