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961.
962.
Although new venture success is frequently investigated in entrepreneurship, economics, and psychology, the studies published to date vary widely in their theoretical basis, study design, and research methodology. Based on organizational life‐cycle theory and interactional personality theory, this longitudinal study analyses predictors of venture survival. Of 354 small business owners observed over 8 years, 283 (79.9%) still had active businesses at the end of the observation period. A survey instrument was developed to measure the relevant characteristics of the entrepreneurs, their resources, and the environment. Logistic regression models predicting medium‐ and long‐term business survival included these characteristics and the interactions between them entered stepwise as blocks. Startup decisions (line of business, type, and size of planned business) were used as control variables. Much of the variance is explained by our research model (Nagelkerkes R2=.36 for survival at 4 years, and .33 for survival at 8 years). Although long‐term business survival is predicted by the individual variables of startup size and social capital (networks), a larger part of the variance is explained by environment/resource interactions.  相似文献   
963.
The relationship between reaction time and both state and trait personality variables was investigated in 37 participants after 30 h of sleep deprivation. Regression analyses suggested that endorsement of greater Novelty Seeking, anger/hostility, and depression/dejection, and less confusion, was associated with greater reaction time declines on one Multi-Attribute Task Battery index after sleep deprivation. Further, greater Novelty Seeking and depression/dejection, and less vigor/activity, was associated with greater reaction time declines after sleep deprivation on another Multi-Attribute Task Battery index. Additional correlational analyses indicated that better reaction times were associated with greater Novelty Seeking and lower anger/hostility prior to sleep deprivation, and less confusion/bewilderment following sleep deprivation. Findings suggest that both state and trait personality variables are associated with reaction time performance following sleep deprivation.  相似文献   
964.
In masked priming tasks responses are usually faster when prime and target require identical rather than different responses. Previous research has extensively manipulated the nature and number of response-affording stimuli. However, little is known about the constraints of masked priming regarding the nature and number of response alternatives. The present study explored the limits of masked priming in a six-choice reaction time task, where responses from different fingers of both hands were required. We studied participants that were either experts for the type of response (skilled typists) or novices. Masked primes facilitated responding to targets that required the same response, responses with a different finger of the same hand, and with a homologous finger of the other hand. These effects were modulated by expertise. The results show that masked primes facilitate responding especially for experts in the S–R mapping and with increasing similarity of primed and required response.  相似文献   
965.
The objective of this study was to examine associations between specific dimensions of the multi-dimensional cumulative risk index (CRI) and asthma morbidity in urban, school-aged children from African American, Latino and Non-Latino White backgrounds. An additional goal of the study was to identify the proportion of families that qualify for high-risk status on each dimension of the CRI by ethnic group. A total of 264 children with asthma, ages 7–15 (40% female; 76% ethnic minority) and their primary caregivers completed interview-based questionnaires assessing cultural, contextual, and asthma-specific risks that can impact asthma morbidity. Higher levels of asthma-related risks were associated with more functional morbidity for all groups of children, despite ethnic group background. Contextual and cultural risk dimensions contributed to more morbidity for African-American and Latino children. Analyses by Latino ethnic subgroup revealed that contextual and cultural risks are significantly related to more functional morbidity for Puerto Rican children compared to Dominican children. Findings suggest which type of risks may more meaningfully contribute to variations in asthma morbidity for children from specific ethnic groups. These results can inform culturally sensitive clinical interventions for urban children with asthma whose health outcomes lag far behind their non-Latino White counterparts.  相似文献   
966.
Background. Recent literature on emotions in education has shown that competence‐ and value‐related beliefs are important sources of students' emotions; nevertheless, the role of these antecedents in students' daily functioning in the classroom is not yet well‐known. More importantly, to date we know little about intra‐individual variability in students' daily emotions. Aims. The objectives of the study were (1) to examine within‐student variability in emotional experiences and (2) to investigate how competence and value appraisals are associated with emotions. It was hypothesized that emotions would show substantial within‐student variability and that there would be within‐person associations between competence and value appraisals and the emotions. Sample(s). The sample consisted of 120 grade 7 students (52%, girls) in 5 randomly selected classrooms in a secondary school. Method. A diary method was used to acquire daily process variables of emotions and appraisals. Daily emotions and daily appraisals were assessed using items adapted from existing measures. Results. Multi‐level modelling was used to test the hypotheses. As predicted, the within‐person variability in emotional states accounted for between 41% (for pride) and 70% (for anxiety) of total variability in the emotional states. Also as hypothesized, the appraisals were generally associated with the emotions. Conclusions. The within‐student variability in emotions and appraisals clearly demonstrates the adaptability of students with respect to situational affordances and constraints in their everyday classroom experiences. The significant covariations between the appraisals and emotions suggest that within‐student variability in emotions is systematic.  相似文献   
967.
Despite the ubiquity and importance of metaphor in thought and communication, its neural mediation remains elusive. We suggest that this uncertainty reflects, in part, stimuli that have not been designed with recent conceptual frameworks in mind or that have been hampered by inadvertent differences between metaphoric and literal conditions. In this article, we begin addressing these shortcomings by developing a large, flexible, extensively normed, and theoretically motivated set of metaphoric and literal sentences. On the basis of the results of three norming studies, we provide 280 pairs of closely matched metaphoric and literal sentences that are characterized along 10 dimensions: length, frequency, concreteness, familiarity, naturalness, imageability, figurativeness, interpretability, valence, and valence judgment reaction time. In addition to allowing for control of these potentially confounding lexical and sentential factors, these stimuli are designed to address questions about the role of novelty, metaphor type, and sensory-motor grounding in determining the neural basis of metaphor comprehension. Supplemental data for this article may be downloaded from http://brm.psychonomic-journals .org/content/supplemental.  相似文献   
968.
Brief experience with reliable spectral characteristics of a listening context can markedly alter perception of subsequent speech sounds, and parallels have been drawn between auditory compensation for listening context and visual color constancy. In order to better evaluate such an analogy, the generality of acoustic context effects for sounds with spectral-temporal compositions distinct from speech was investigated. Listeners identified nonspeech sounds—extensively edited samples produced by a French horn and a tenor saxophone—following either resynthesized speech or a short passage of music. Preceding contexts were “colored” by spectral envelope difference filters, which were created to emphasize differences between French horn and saxophone spectra. Listeners were more likely to report hearing a saxophone when the stimulus followed a context filtered to emphasize spectral characteristics of the French horn, and vice versa. Despite clear changes in apparent acoustic source, the auditory system calibrated to relatively predictable spectral characteristics of filtered context, differentially affecting perception of subsequent target nonspeech sounds. This calibration to listening context and relative indifference to acoustic sources operates much like visual color constancy, for which reliable properties of the spectrum of illumination are factored out of perception of color.  相似文献   
969.
The aim of this study was to investigate the consequences of friend networking sites (e.g., Friendster, MySpace) for adolescents' self-esteem and well-being. We conducted a survey among 881 adolescents (10-19-year-olds) who had an online profile on a Dutch friend networking site. Using structural equation modeling, we found that the frequency with which adolescents used the site had an indirect effect on their social self-esteem and well-being. The use of the friend networking site stimulated the number of relationships formed on the site, the frequency with which adolescents received feedback on their profiles, and the tone (i.e., positive vs. negative) of this feedback. Positive feedback on the profiles enhanced adolescents' social self-esteem and well-being, whereas negative feedback decreased their self-esteem and well-being.  相似文献   
970.
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