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A series of protein types have been characterized with respect to their interaction with low dextrose equivalent corn starch hydrolysates. From an assessment of the chemical modification of selected functional groups, classical denaturation studies, gel filtration and precipitation with tri-chloro-acetic acid, the partial basis for molecular interaction has been elucidated. Although all proteins under investigation were prominent components of a variety of food systems, particular emphasis was placed on the behavior of β-lactoglobulin and selected soy fractions. Results from the modification and denaturation studies indicated that several factors are required to account for the extent of interaction, but that the predominant effect appears to be non-covalent in nature. In the case of commercial soy proteins, considerable polydispereity was detected prior to the interaction - much of which was doubtless induced during isolation. Many such fragments of this preparation showed self-interacting properties, which could provide a basis for texture in the reported system. The starch hydrolysates appear to exhibit a protective effect against excessive protein aggregation, which could have significance in retention of nutritional value during food processing. 相似文献
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Enterohemorrhagic Escherichia coli O157:H7 (EHEC) is recognized as a frequent cause of gastroenteritis ranging from mild to severe bloody diarrhea. The Shiga-like toxin produced by EHEC can result in hemolytic uremic syndrome, now the major cause of acute kidney failure in children in the United States. Inadequately cooked beef is most commonly implicated in the transmission of EHEC, although only a small fraction of cattle appear to harbor the organism. In several studies EHEC positive herds were detected only in the summer months correlating with the occurrence of human infections. Numerous E. coli strains have been shown to enter a viable but nonculturable (VBNC) state as a result of environmental stresses, including low temperature. Using traditional plating methods and the BacLight Molecular Probe, we monitored EHEC strains incubated in river water (RW) and artificial sea water (ASW) at temperatures of 5C and 25C for their entry into the VBNC state. EHEC strains remained culturable for over 40 days in both ASW and RW incubated at 25C. In ASW, these levels were higher than a non-EHEC control. At 5C, the number of culturable EHEC cells dropped gradually in both RW and ASW. Using the BacLight Molecular Probe, we were able to demonstrate that these cells, though not culturable, were viable indicating entry into the VBNC state. Our study suggests that temperature and not salinity is the primary signal for entry into this state . 相似文献
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WILLIAM PETERMAN 《Journal of Urban Affairs》1989,11(1):53-68
ABSTRACT: Interest in options to conventional public housing management is growing. This article reviews five management options: resident participation, resident management, community development corporations, cooperatives, and mutual housing associations. Each option is evaluated with respect to the likelihood of reaching 12 structural, improvement, and resident well-being objectives. Although each of the five has some positive characteristics, resident management, community development corporations, and mutual housing associations are found to be the preferable options. This is because they provide a balance between institutional support and resident involvement. 相似文献
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ABSTRACT: In this article we analyze gated communities as a nexus of social and spatial relations within the context of urban inequality. We apply Tickamyer's (2000) sociological framework for incorporating space into the study of inequality, which allows us to substantiate the arguments that the process of gating increases urban inequality. The contributions of this article are three: (1) We generate a new systematic theoretical approach toward the study of gated communities, which we consider as middle range theory; (2) We argue that gated communities reproduce the existing levels of social stratification and that they also define a new, permanent differentiation order in the spatial organization of cities in the United States (in this respect we also arrive at six hypotheses, which can be tested in future research); (3) We introduce the term “gating machine,” where the combination of the interests and actions of local governments, real estate developers, the media, and consumers suggest that prevailing structural conditions assure the future proliferation of gated communities. 相似文献
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A multifactorial design was used to study the role of protein (Pro), polyphenols (PP), sucrose (Suc), pectin (Pec), potassium (K), and pH in the formation of haze in wine. Model wines (32) containing two levels of each factor plus yeast and nutrients were made and allowed to ferment to 0 Brix. Measurements of transmission at 633 nm (%T) following heating showed that PP, Pro, Pro*PP, Pec, and PP*Pec were all significant factors affecting turbidity. Molecular weight and size determinations by size‐exclusion chromatography‐laser light scattering indicated that molecular weight depended on Suc*Pec, Pro*PP*pH, and Pro*Pec*pH while molecular radius depended on PP*Suc*Pec, Pro, PP*Pec, and Suc*pH. Measurement of protein after filtration showed that Pro, PP, Pro*PP, and Pro*PP*pH were all factors. Laser diffraction studies showed three primary peaks in the range 0.05 ‐ 800 μm. The smallest size range had Pro*pH as a significant factor, while the largest had Pec and Pro*K as factors. These results indicate that a variety of factors are important to haze formation and that measurement of particle size, distribution, and interactions depends upon the instrument used to measure it. 相似文献
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16 SS ON AN ACUTE HOSPITAL WARD WERE TESTED ON RECOGNITION OF STATEMENTS MADE DURING WARD COMMUNITY MEETINGS WHICH THEY HAD ATTENDED. STATEMENTS WERE CATEGORIZED ACCORDING TO THE HILL INTERACTION MATRIX, AND THE AVERAGE MEMORY SCORES FOR 5 OF THE HILL CATEGORIES WERE COMPARED. RESULTS INDICATE THAT STATEMENTS ABOUT WARD BUSINESS AND ABOUT BEHAVIOR OF SS DURING THE MEETING WERE BEST REMEMBERED, WHILE STATEMENTS ABOUT SS' LIVES INDEPENDENT OF OTHER MEMBERS OF THE GROUP AND GENERALIZATIONS ABOUT HOW PSYCHOTHERAPY WORKS WERE LESS WELL REMEMBERED. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献