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71.
Investigated the extent to which hypnotic susceptibility could be modified by means of induced positive expectancies and written instructions that were designed to correct misconceptions concerning hypnosis as well as to provide concrete methods for experiencing hypnosis. 40 undergraduates were given a baseline test of hypnotic susceptibility and then randomly assigned to 1 of 4 conditions. Ss receiving the positive expectancy were given false personality test feedback that they were good hypnotic Ss prior to a criterion hypnotic scale. Ss receiving the written instructions were given 10 min to read the information prior to the hypnotic test. Other Ss browsed through magazines prior to testing in hypnosis. Both positive expectancies and written instructions were significantly effective in increasing susceptibility in comparison with practice only. Theoretical explanations are advanced and the implications of these findings are considered. (26 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Zinc oxide (ZnO) is an inorganic compound widely used in everyday applications. ZnO is currently listed as a generally recognized as safe (GRAS) material by the Food and Drug Administration and is used as food additive. The advent of nanotechnology has led the development of materials with new properties for use as antimicrobial agents. Thus, ZnO in nanoscale has shown antimicrobial properties and potential applications in food preservation. ZnO nanoparticles have been incorporated in polymeric matrices in order to provide antimicrobial activity to the packaging material and improve packaging properties. This review presents the main synthesis methods of ZnO nanoparticles, principal characteristics and mechanisms of antimicrobial action as well as the effect of their incorporation in polymeric matrices. Safety issues such as exposure routes and migration studies are also discussed.  相似文献   
77.
Slices (1.5 mm thick) of green papaya were impregnated through osmotic dehydration with a blackberry juice–sucrose solution to produce an intermediate moisture product. The effect of processing temperature (T) and sucrose-added molality (msucrose) on mass transfer during the operation was assessed, using a response surface methodology (RSM). The RSM was used to model water loss, sugar and anthocyanin gain during the process. Increasing sucrose molality resulted in increasing water loss and sugar gain, but decreasing anthocyanin gain. Water transfer therefore limits anthocyanin impregnation, but not sucrose incorporation. Afterwards, the impact of heat treatment at high temperatures was analysed, using numerical simulation. The conditions of the combined process, designed to achieve an anthocyanin-rich final product, are low sucrose-added molalities (sucrose molality < 1 mol kg–1) and high processing temperatures (> 50 ºC) for osmotic dehydration, coupled with high-temperature, short-time (HTST) heat treatments for product stabilisation.  相似文献   
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This paper describes a methodology to establish an optimal process design for prickly pear wine production that preserves the peculiar and unique traits of traditional products, generating at the same time, technical information for appropriate design of both bioreactor and overall process. The strategy includes alcoholic fermentation optimization by the mixed native culture composed by Pichia fermentans and Saccharomyces cerevisiae, followed by malolactic fermentation optimization by Oenococcus oeni. The optimization criteria were based on multiple output functions: alcohol content, volatile compounds profile, organic acids profile, and compound contents related to color, which were analyzed by spectroscopy–chromatography methods and sensory analysis. The results showed that the mixed culture inoculated into a bioreactor containing prickly pear juice with 20 °Bx of fermentable sugars concentration, processed at a constant temperature of 20 °C for 240 h, leads to a fermented product with 9.93% (v/v) total alcohol content, and significant abundance of volatile compounds, which provide fruity and ethereal aromatic notes, complemented by a lively but not unpleasant acidity. This young wine was further subjected to malolactic fermentation at constant temperature (16 °C) for 192 h, decreasing malic acid, and balancing volatile compounds contents, thus resulting in a product with better aroma and flavor perception, and a velvety feeling of long aftertaste. Repeated assays showed that the process is stable, predictable, controllable, and reproducible. These results were used for process design and spreadsheet construction in order to simulate the process, and properly select and size the equipment required for such process.  相似文献   
79.
In this study, antioxidant biodegradable films based on pea protein and alpha-tocopherol were successfully developed by solution casting. The effect of both the homogenization conditions (rotor–stator and microfluidizer) and the relative humidity (RH) on the microstructure and physical properties (transparency, tensile, oxygen and water vapour barrier properties) of pea protein/alpha-tocopherol-based films was evaluated. The addition of alpha-tocopherol produced minimal changes in the films’ transparency, while providing them with antioxidant properties and improved water vapour and oxygen barrier properties (up to 30 % in both water vapour and oxygen permeability) when films were at low and intermediate RH. The addition of alpha-tocopherol in microfluidized films gave rise to an increase in their resistance to break and extensibility (up to 27 % in E values) at intermediate and high RH. These results add a new insight into the potential of employing pea protein and alpha-tocopherol in the development of fully biodegradable antioxidant films which are of interest in food packaging.  相似文献   
80.
A feasibility study of the preparation of quality control materials for the analysis of medicated feeds has been carried out. Two analytical methodologies for the analysis of sulfonamides in feeds were developed, validated and applied to homogeneity and stability studies. Pig feeds spiked with sulfadiazine and sulfadimidine were prepared. The drugs were spiked at 500 µg g?1, representing what can be expected in a commercial medicated feed, and at 2 and 5 µg g?1, which roughly correspond to drug-free feeds cross-contaminated during the fabrication process. The homogeneity of both the bulk and the bottled materials was verified. A stability study of the materials containing 2 and 5 µg g?1 of sulfonamides was carried out over an 18-month period at room temperature, at 4°C and ?20°C. The determination of sulfadiazine and sulfadimidine in samples coming from these homogeneity and stability studies of the quality control materials was carried out by high-performance liquid chromatography (HPLC) with either ultraviolet light or fluorimetric detection, depending on the concentration of the analytes in the samples.  相似文献   
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