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201.
Transparency: relation to depth, subjective contours, luminance, and neon color spreading 总被引:2,自引:0,他引:2
The perception of transparency is highly dependent on luminance and perceived depth. An image region is seen as transparent if it is of intermediate luminance relative to adjacent image regions, and if it is perceived in front of another region and has a boundary which provides information that an object is visible through this region. Yet, transparency is not just the passive end-product of these required conditions. If perceived transparency is triggered, a number of seemingly more elemental perceptual primitives such as color, contour, and depth can be radically altered. Thus, with the perception of transparency, neon color spreading becomes apparent, depth changes, stereoscopic depth capture can be eliminated, and otherwise robust subjective contours can be abolished. In addition, we show that transparency is not coupled strongly to real-world chromatic constraints since combinations of luminance and color which would be unlikely to arise in real-world scenes still give rise to the perception of transparency. Rather than seeing transparency as a perceptual end-point, determined by seemingly more primitive processes, we interpret perceived transparency as much a 'cause', as an 'effect'. We speculate that the anatomical substrate for such mutual interaction may lie in cortical feed-forward connections which maintain modular segregation and cortical feedback connections which do not. 相似文献
202.
The purpose of this study was to determine the type of school organization that most benefited ninth-grade students. Results indicated that ninth graders in the junior high school setting participated significantly more in extracurricular activities and achieved significantly higher academically than did ninth graders in the senior high school setting. 相似文献
203.
Peer-group association and adolescent tobacco use 总被引:10,自引:0,他引:10
S Sussman C W Dent A W Stacy C Burciaga A Raynor G E Turner V Charlin S Craig W B Hansen D Burton 《Journal of abnormal psychology》1990,99(4):349-352
Mosbach & Leventhal (1988) examined the relation of cigarette smoking to peer-group identification in rural Wisconsin adolescents. They found that among dirts (problem-prone youth), regulars (average youth), hot-shots (good social or academic performers), and jocks (athletes), youth most likely to smoke were dirts and hot-shots. We performed a replication with a Southern California cohort and also for use of smokeless tobacco. We hypothesized that jocks would be the main users of smokeless tobacco. We identified the same groups and an additional one, skaters (skateboarders or surfers). As Mosbach & Leventhal found, cigarettes were used most by dirts. Contrary to their results, but consistent with other research, we found that hot-shots were least likely to smoke. Contrary to our prediction, we found that skaters and dirts were more likely to use smokeless tobacco than were jocks. Our data show that both tobacco forms are used by problem-prone youth. 相似文献
204.
Political consumer behaviour among university students in Brazil and Germany: The role of contextual features and core political values
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Patrick F. Kotzur Cláudio V. Torres Karina K. Kedzior Klaus Boehnke 《International journal of psychology》2017,52(2):126-135
This study investigates the relationship between political consumerism and core political values (CPVs) among university students in Brazil (N = 414) and Germany (N = 222). Despite the prerequisite to endorse values that are compatible with political consumerism, contextual features of one's immediate environment might affect overall levels of political consumerism. Our results show that political consumerism is significantly associated with higher income in Brazil (but not in Germany). After controlling for income, political consumerism was practised more frequently in Germany than in Brazil, in urban compared with rural areas, and was not dependent on gender. The urban–rural split was stronger in Brazil than in Germany. These results confirm our hypothesis that contextual features are associated with political consumerism. Furthermore, the political value Equality positively predicted political consumerism in both countries. In contrast, Traditional Morality and support of Free Enterprise negatively predicted political consumerism, although the effect sizes of these relationships were only small. These results suggest that political consumerism among university students is widespread in Germany but not in Brazil. Interestingly, regardless of its low prevalence in Brazil, political consumerism is positively associated with the CPV of Equality among university students in both countries. 相似文献
205.
World famous actor-comedian Charlie Chaplin once said that “A day without laughter is a day wasted”. But try applying the same quote in our work place, with fluctuating markets, unending competition and impossible deadlines; we may find more wasted days than the rest. All of us know what it feels to experience humour, but most of us think twice before having a hearty laugh at our workplace. What is the barrier which stops us from sharing humour at work? This paper attempts to answer this question and aims to understand the concept of humour at workplace and its importance in today’s context. It aims to review existing literature in this field and present the application of Workplace humour in an organizational context to achieve favourable work-related outcomes. In addition to this, the paper also enumerates the different workplace practices that are directly or indirectly related to humour and provide suggestions to organizations on how to use this powerful tool to bring about organizational effectiveness. 相似文献
206.
207.
Cross-sectional studies have found older adults to have lower levels of emotional distress after natural disasters. The maturation hypothesis suggests that older adults are less reactive to stress events, whereas the inoculation hypothesis argues that prior experience with disaster is protective. One hundred and sixty-six adults aged 30 to 102 were interviewed regarding the 1994 Northridge earthquake. Longitudinal data were available on depressed mood before and after the earthquake. The maturation hypothesis was generally not supported. The young-old were least depressed; however, this age difference was present prior to the earthquake. The old-old showed lowest levels of earthquake-specific rumination, but age did not buffer the relationship between damage exposure and rumination. The inoculation hypothesis was supported for depressed mood. Prior earthquake experience was related to lower postearthquake depression scores. 相似文献
208.
Cook KV 《Adolescence》2000,35(140):717-730
This study was designed to explore Freeman's (1986) finding that the institution that made the greatest contribution to male African-American youths' socioeconomic success was the church. Thirty-two African-American, Haitian-American, and Latino male and female teenagers--16 drawn from inner-city Protestant churches and 16 comparison teenagers from the same communities-were interviewed. The interviews revealed that churched teenagers were less stressed and less likely to have psychological problems than were teenagers in the comparison group. They also appeared more likely to be living with both biological parents, less likely to have a family member on welfare, and more likely to have a job when compared with the other teenagers. They described the church as being central to their lives and as having multiple functions, many of which have been identified in the resilience literature as contributing to positive developmental outcomes. Results are interpreted in light of the transactional model, and recommendations are made, such as expanding the role of the church within these ethnic communities. 相似文献
209.
Research on the benefits of social support groups has been inconclusive. One reason is that individual differences in intervention responses have rarely been examined. The authors determined the extent to which individual difference variables moderated the effects of an information-based educational group and an emotion-focused peer discussion group on the mental and physical functioning of women with breast cancer (n = 230). The authors administered the SF-36 (S.E. Ware, K.K. Snow, M. Kosinski, & B. Gandek, 1993), a multidimensional quality of life instrument, pre- and postintervention. Educational groups showed greater benefits on the physical functioning of women who started the study with more difficulties compared with less difficulties (e.g., lacked support or fewer personal resources). Peer discussion groups were helpful for women who lacked support from their partners or physicians but harmful for women who had high levels of support. Implications of these results for clinical interventions are discussed. 相似文献
210.
Mean response times, variability, and skew in the responding of ADHD children: a response time distributional approach 总被引:7,自引:0,他引:7
Response time (RT) distributions from three fixed foreperiod conditions (2, 4, and 8 s) in a warned four-choice RT task were obtained for a group of boys with attention-deficit/hyperactivity disorder, combined type (ADHD; n = 17) and for two groups of normal control boys (age-matched, n = 18, and younger-aged, n = 10). Quantitative measures of distributional shape were derived by fitting the ex-Gaussian distributional model to the individual RT data. Statistical results indicate that the ADHD distributions differ from the age-matched control distributions with respect to the size of the tail (larger for the ADHD boys), but differ from the younger control distributions with respect to the location of the leading edge (slower for the younger control boys). Receiver operating characteristic (ROC) results reveal that the ex-Gaussian exponential component is highly diagnostic of the ADHD boys. 相似文献