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In an investigation of S. E. Asch's (1955) findings regarding the role of attribution processes in mediating conformity and dissent, 160 undergraduates listened to 24 pairs of tones and after each pair judged which tone was longer in duration. In a control condition, Ss simply wrote private judgments after hearing each pair of tones. As predicted, the majority's impact was minimal when differences in judgment could readily be attributed to corresponding differences in potential payoffs. The majority's influence increased when the only satisfactory explanation for disagreement demanded the postulation of differences between the "priorities" of the dissenter and those of the group. Conformity pressures became most intense when there was no satisfactory explanation and dissent could be attributed only to serious perceptual incapacity on the part of the dissenter or of the majority. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
43.
Eight children with hydrocephalus showed signs of posterior fossa tonsillar impaction despite arrest of the hydrocephalus and patency of their CSF shunts. Contrast studies performed because of their clinical deterioration demonstrated cerebellar tonsillar herniation, and at posterior fossa decompression, this was confirmed in all cases. Improvement followed decompression. The pathogenesis of a state of cephalocranial disproportion following successful treatment of hydrocephalus resulting in symptomatic tonsillar herniation, is discussed.  相似文献   
44.
Conducted 2 experiments each with 10 male hooded laboratory rats. In Exp I, Ss responded on an FI schedule in which several differentially cued 1 or 3 food-pellet intervals preceded cued 2 food-pellet intervals. Exp II contained only intervals ending with 1 or 3 pellets and presorted in a quasi-random order. In both experiments, absolute performance varied as a function of the preceding and the current amount of reinforcement and the minute of the interval. The distribution of responses within an interval varied as a function of the preceding amount of reinforcement and the amount of reinforcement which would be delivered at the end of the current interval. Results are discussed in terms of a frustration interpretation and of an alternative hypothesis based on an extension of the inhibitory effects of reinforcement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
45.
Metal sorption mechanisms were investigated for strontium, cobalt, and lead using sodium chloride, sodium nitrate, and sodium perchlorate as background electrolytes and quartz as the adsorbent. Spectroscopic analyses of concentrated sorption samples were evaluated for their ability to provide insight into the controlling sorption process for more dilute systems. For strontium, outer-sphere complexes identified using X-ray absorption spectroscopy (XAS) of concentrated samples were consistent with macroscopic sorption data collected in more dilute systems. XAS results indicated that cobalt formed a new solid phase upon sorption to silica. Macroscopic studies of cobalt sorption supported the spectroscopic data for total cobalt concentrations of 10(-5) M, regardless of the background electrolyte composition or concentration. At a lower total cobalt concentration (10(-7) M), adsorption appeared to be the prevailing mechanism of cobalt removal. Spectroscopic results suggested that lead adsorbed as an inner-sphere complex on silica. The decrease of lead removal with increasing chloride concentration was attributed to competition with aqueous lead-chloride complexes, based on thermodynamic calculations.  相似文献   
46.
This study consisted of two trials aiming to evaluate, for the first time, the antioxidant potential of rooibos in meat products. With this purpose, the first trial evaluated three unfermented (green) rooibos forms (dried leaves, water extract, freeze-dried extract) added at 2% inclusion level to ostrich meat patties on an 8-day shelf-life trial. A Control group without green rooibos inclusion was also considered. The second trial evaluated the addition of different concentrations (0%, 0.25%, 0.5% and 1%) of a fermented rooibos extract to nitrite-free ostrich salami. The 2% green rooibos inclusion considerably lowered the TBARS content of ostrich patties, in this way extending their shelf-life. The fermented form (0.5% and 1%) was also effective in delaying lipid oxidation in ostrich salami until 15 days of ripening. The antioxidant potential of both green and fermented forms of rooibos in meat products was confirmed, even if its effect on lipid oxidation requires further study and long-term effects are not yet fully understood.  相似文献   
47.
Our objective was to assess the pasture productivity and forage characteristics of 2 fall-grown oat (Avena sativa L.) cultivars, specifically for extending the grazing season and reducing reliance on harvested forages by replacement dairy heifers. A total of 160 gravid Holstein heifers (80 heifers/yr) were stratified by weight, and assigned to 1 of 10 identical research pens (8 heifers/pen). Initial body weights were 480 ± 43.5 kg in 2011 and 509 ± 39.4 kg in 2012. During both years of the trial, four 1.0-ha pasture replicates were seeded in August with Ogle oat (Schumitsch Seed Inc., Antigo, WI), and 4 separate, but similarly configured, pasture replicates were seeded with Forage Plus oat (Kratz Farms, Slinger, WI). Heifer groups were maintained as units, assigned to specific pastures, and then allowed to graze fall-oat pastures for 6 h daily before returning to the barn, where they were offered a forage-based basal total mixed ration. Two heifer groups were retained in confinement (without grazing) as controls and offered the identical total mixed ration as pasture groups. During 2011, available forage mass increased with strong linear and quadratic effects for both cultivars, peaking at almost 9 Mg/ha on October 31. In contrast, forage mass was not affected by evaluation date in 2012, remaining ≤2,639 kg/ha across all dates because of droughty climatic conditions. During 2012, Ogle exhibited greater forage mass than Forage Plus across all sampling dates (2,678 vs. 1,856 kg/ha), largely because of its more rapid maturation rate and greater canopy height. Estimates of energy density for oat forage ranged from 59.6 to 69.1% during 2011, and ranged narrowly from 68.4 to 70.4% during 2012. For 2011, responses for both cultivars had strong quadratic character, in which the most energy-dense forages occurred in mid November, largely due to accumulation of water-soluble carbohydrates that reached maximum concentrations of 18.2 and 15.1% for Forage Plus and Ogle, respectively. Across the 2-yr trial, average daily gain for grazing heifer groups tended to be greater than heifers remaining in confinement (0.85 vs. 0.74 kg/d), but both management strategies produced weight gains within reasonable proximity to normal targets for heifers in this weight range. Fall-grown oat should be managed as stockpiled forage for deferred grazing, and good utilization of fall-oat forage can be accomplished by a one-time removal of standing forage, facilitated by a single lead wire advanced daily to prevent waste.  相似文献   
48.
PURPOSE: Polyvinyl alcohol (PVA) is a successful tear film stabiliser and is widely used in comfort drops and some soft contact lens materials. A PVA-containing lens, nelfilcon A has been modified to include additional (non-functional) PVA in order to provide improved comfort. This study aims to examine the clinical performance of this nelfilcon A lens with AquaRelease (AquaRelease). METHODS: Two contralateral, investigator masked, open label, subjective and objective evaluations were conducted. The first examined the effect of adding increased molecular weight PVA to nelfilcon A (n=5), and the second compared this AquaRelease lens to ocufilcon B (n=34). The principal measures were non-invasive break-up time (NIBUT) and subjective comfort, which were assessed at the beginning and end of a week of daily wear, and three times throughout 1 day at 8, 12 and 16 h. RESULTS: All subjects successfully completed the daily wearing schedule of 16h. On initial insertion, subjective comfort and NIBUT improved for AquaRelease than original nelfilcon A lenses (p<0.05). Initial comfort was better for AquaRelease compared to ocufilcon B lenses (p=0.01); however, NIBUT was not statistically different (11.7+/-15.6s versus 8.4+/-6.8s; p=0.26). Subjective comfort decreased with time (p<0.001), but there was no significant difference between AquaRelease and ocufilcon B lenses (p=0.16). NIBUT was not significantly affected by time (p=0.56) or between lenses (p=0.33). At the end of a weeks' wear, subjective initial, end-of-day, overall comfort and vision were rated significantly better with AquaRelease than ocufilcon B (p<0.01). CONCLUSIONS: Release of additional non-functionalised PVA from the nelfilcon A lenses appears to enhance comfortable contact lens wear.  相似文献   
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