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31.
The authors studied 2 patients, S.M. and R.N., to examine perceptual organization and its relationship to object recognition. Both patients had normal, low-level vision and performed simple grouping operations normally but were unable to apprehend a multielement stimulus as a whole. R.N. failed to derive global structure even under optimal stimulus conditions, was less sensitive to grouping by closure, and was more impaired in object recognition than S.M. These findings suggest that perceptual organization involves a multiplicity of processes, some of which are simpler and are instantiated in lower order areas of visual cortex (e.g., collinearity). Other processes are more complex and rely on higher order visual areas (e.g., closure and shape formation). The failure to exploit these latter configural processes adversely affects object recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
32.
Maintains that J. M. Stoppard's (see record 1989-29654-001) discussion of the adequacy of cognitive/behavioral theories for understanding depression in women (1) fails to adequately consider methodological issues in investigating sex differences in psychopathology and (2) misreads the cognitive/behavioral theories as having a stagnant, simplistic view of psychopathology. (0 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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60 care receivers (aged 62–100 yrs) and 39 of their caregivers judged vocal nonverbal messages prepared from audiotapes of caregivers interacting with their co-workers and elderly nursing home residents. The relationship between these judgments and, respectively, the functional ability of the aged judges and the expectations of the elderly held by the caregivers were investigated. The stimulus tape judged consisted of 3 types of messages: caregivers' speech to care receivers in baby talk, caregivers' speech to care receivers not in baby talk, and speech to other caregivers assumed to be in normal adult speech. For the elderly judges, lower functional ability scores were associated with a greater liking for baby talk speech as compared to other speech, but no relationships were found for their judgments of "soothing" or "irritating." For caregivers, expectancy was associated with their predictions of residents' liking for baby talk speech and caregivers' endorsements that adult speech would not be effective for interacting with care receivers. Results suggest that variations in caregiver expectancy may operate through a common social stereotype of the elderly. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
35.
This article is the continuation of M. Schommer's (1993) study, in which the development of secondary students' beliefs about the nature of knowledge and learning, or epistemological beliefs, was examined. High school students (N?=?69) completed an epistemological questionnaire as freshmen in 1992 and as seniors in 1995. Repeated-measures analyses revealed that their beliefs in fixed ability to learn, simple knowledge, quick learning, and certain knowledge changed as they neared the end of their 4th year in high school. In addition, the less students believed in quick learning, the better grade point average they earned. These results are consistent with a cross-sectional study (M. Schommer, 1993) establishing substantial differences in students' epistemological beliefs across the high school years and thus strengthen the case that there is development of epistemological beliefs related to learning during high school. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
36.
Describes results of the American Psychological Association's 1st 4 annual Doctorate Employment Surveys from 1975 to 1978. The surveys, conducted in the winter following receipt of degrees, found a low rate of unemployment: The percentage of doctorate recipients who were unemployed and seeking employment was 3.0% in 1975 and 2.0% or lower in subsequent years. Approximately half of those unemployed at the time of the survey had been employed in psychology-related work at a professional level before receiving their doctorates. Among those employed full-time, the percentage employed in academic settings declined, and the percentages employed in human service settings and business, government, and other settings increased. Despite the decline in academic employment, 97.1% reported that their jobs were related to psychology, and 89.0% reported that their jobs were commensurate with their training. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
37.
Zooplankton in a nearshore area in southeastern Lake Michigan displayed strong seasonal and depth-related trends in abundance (#/m3) during the period 1971 to 1977. Depth-related assemblages defined by principal component analysis varied with season. From mid-spring to mid-autumn, zooplankton assemblages were strongly related to water depth. In general, zooplankton were least abundant in the inner region (5–10 m) where small organisms such as nauplii, Asplanchna spp., and Bosmina longirostris and epibenthic organisms such as Eurytemora affinis dominated. Zooplankton were most abundant between 20 and 30 m, with a peak July 1972–1977 mean density of 87,000/m3. Larger zooplankton, including Cyclops spp., Diaptomus spp., Daphnia spp., and Eubosmina coregoni dominated the outer region (20–50 m). During autumn, the inner region was dominated by cladocerans while the outer region was dominated by copepods. After thermal stratification disappeared in late autumn and before the thermal bar moved beyond the survey area in early spring, zooplankton tended to occur in higher densities in the shallow depths of the survey area. Also, in contrast to the mid-spring to mid-autumn period, zooplankton occurred in similar compositions over the survey grid. Factors implicated in producing seasonal differences in abundance patterns include temperature regimes, phytoplankton standing stocks, and predation by fish and invertebrates.  相似文献   
38.
显示器设备制造商之间有着共同的发展计划,电子流体显色剂和喷墨印刷头的设计者们已成功实现了大型电子显示板平板显示器引导线制造中特制的喷墨印刷头的发展计划。这种喷墨印刷头正在被认作各种大面积液晶显示器制造工艺的精密淀积设备。现这种喷墨型设备的市场需求正在不断增长。对于通过单独整理每个喷嘴通道进行一个128喷嘴的压力式喷墨印刷头流体下降位置控制情况给予了介绍。这种印刷头用作大型电子显示板显示器引导线的制造,通过采用不同的印刷头便可使大面积衬底的生产率得到提高的机会。讨论了通过印刷头和系统设计提高生产率实质。其它的高技术市场为利用精密降落位置和降落量控制。并给出了采用喷嘴制作印刷电路极的一些例子。  相似文献   
39.
BACKGROUND: We completed a study over a 200‐day period examining the stability of limonin glucoside formulated into three beverage matrices. RESULTS: Beverages containing limonin glucoside were found to contain limonin (0.13–20.10 mg L?1) during their initial testing; however, these concentrations were directly attributable to the presence of contaminating limonin in the particular lot of limonin glucoside used to prepare the beverage and did not increase over the test period. Likewise, limonin glucoside concentrations did not vary significantly, with the exception of the beverage matrix that included vitamin B2. Exposure of the vitamin B2‐containing beverages to light resulted in a rapid reduction in the limonin glucoside content. Liquid chromatographic–mass spectrometric and nuclear magnetic resonance results from the analyses of pre‐ and post‐light exposed beverages suggest photooxidation of the furan moiety as the likely degradation pathway. CONCLUSION: Results from this study indicate that limonin glucoside is resistant to degradation into limonin, the stability of limonin glucoside formulated into beverages exceeds six months and that limonin glucoside should not be formulated into beverages containing vitamin B2 unless the beverages are protected from light. Published in 2008 by John Wiley & Sons, Ltd.  相似文献   
40.
Rheological and interfacial tension data were employed to predict the morphology and thermal and mechanical properties of noncompatibilized and compatibilized poly(lactic acid) (PLA)/thermoplastic elastomer (TPE) blends. PLA was melt blended with thermoplastic polyurethane (TPU) and ethylene elastomer (EE) and compatibilized by ethylene–butyl acrylate–glycidyl methacrylate (EBG) in an internal mixer chamber. Both TPU and EE TPEs have higher viscosities than PLA, and the interfacial properties evaluated have revealed better adhesion between domains of PLA–TPU. The efficiency of the compatibilizer agent EBG depended on the TPE type inferred by modifications in the scanning electron microscopy images of PLA/TPE blends and by the Izod impact strength (improved by 23%). The EBG was more effective in the PLA/TPU blend. The TPEs and EBG did not affect the PLA thermal stability, and no thermal event was observed in the usual PLA extrusion and injection temperature range. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47962.  相似文献   
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