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181.
Posttraumatic stress disorder (PTSD) is an anxiety disorder in which an individual re-experiences a traumatic event, avoids situations related to it, and shows excessive arousal. The disorder appears after experiencing a life-threatening event, such as a war or a natural disaster. Thus, the validation of tests which assess the disorder after the earthquake on February 27, 2010, in Chile is crucial for its evaluation and subsequent intervention. The present study includes psychometric data for the Posttraumatic Stress Disorder Checklist-Civilian version (PCL-C) on a sample of 509 survivors of the disaster. Values indicate good psychometric properties of the questionnaire.  相似文献   
182.
In this paper we study some questions concerning ?ukasiewicz implication algebras. In particular, we show that every subquasivariety of ?ukasiewicz implication algebras is, in fact, a variety. We also derive some characterizations of congruence permutable algebras. The starting point for these results is a representation of finite ?ukasiewicz implication algebras as upwardly-closed subsets in direct products of MV-chains.  相似文献   
183.
Speech remains intelligible despite the elimination of canonical acoustic correlates of phonemes from the spectrum. A portion of this perceptual flexibility can be attributed to modulation sensitivity in the auditory-to-phonetic projection, although signal-independent properties of lexical neighborhoods also affect intelligibility in utterances composed of words. Three tests were conducted to estimate the effects of exposure to natural and sine-wave samples of speech in this kind of perceptual versatility. First, sine-wave versions of the easy and hard word sets were created, modeled on the speech samples of a single talker. The performance difference in recognition of easy and hard words was used to index the perceptual reliance on signal-independent properties of lexical contrasts. Second, several kinds of exposure produced familiarity with an aspect of sine-wave speech: (a) sine-wave sentences modeled on the same talker; (b) sine-wave sentences modeled on a different talker, to create familiarity with a sine-wave carrier; and (c) natural sentences spoken by the same talker, to create familiarity with the idiolect expressed in the sine-wave words. Recognition performance with both easy and hard sine-wave words improved after exposure only to sine-wave sentences modeled on the same talker. Third, a control test showed that signal-independent uncertainty is a plausible cause of differences in recognition of easy and hard sine-wave words. The conditions of beneficial exposure reveal the specificity of attention underlying versatility in speech perception.  相似文献   
184.

Objective

This study examined the contributions of maternal bids for joint attention, relationship quality, and infant characteristics, to individual differences in infants’ parallel and joint attention.

Method

Fifty-two 10-month-olds and their mothers were assessed in order to investigate concurrent predictors of infant parallel attention, responding to joint attention, and initiating joint attention.

Results

Parallel attention was predicted by infants’ higher mental development, low expression of negative emotionality, and maternal entertaining behaviors. Responding to joint attention was marginally predicted by total maternal bids for joint attention. Initiating joint attention was predicted by the infants’ low expression of negative emotionality, as well as marginally predicted by fewer maternal teaching behaviors.

Conclusion

These results further the understanding of the factors influencing infant parallel as well as joint attention.  相似文献   
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187.
The influence of students' sociocultural background on academic achievement is a well established fact. Research also points out that sociocultural background is related to students' cognitive abilities and these have an effect on their academic achievement. However, the mediator role of cognitive abilities on the relationship between sociocultural background and academic achievement is less well known. A structural equation model that represents these relationships was tested in a sample (N= 728) of Portuguese junior high school students. Multigroup analysis of the model showed the importance of the cognitive ability mediation effect between sociocultural background and academic achievement in the 7th and 9th grades, but not in the 8th grade. This difference may be the result of the academic transition experienced in the 7th and 9th grades in the Portuguese educational system, which requires parents' higher involvement in school.  相似文献   
188.
Optimism has been classically considered a key trait in entrepreneurs' personality but it has been studied from a psychological point of view only in recent years. The main aim of this research is to study the relationship between dispositional optimism, pessimism and realism as a function of the tendency to create technology-based businesses. A sample of undergraduate students (n= 205) filled in an electronic questionnaire containing the Life Orientation Test-Revised after they were classified as potential technological entrepreneurs, potential general entrepreneurs and non-potential entrepreneurs. Our results show that technology-based entrepreneurs are more optimistic than non-potential entrepreneurs, whereas there were no statistical differences in pessimism and realism. The results are interpreted theoretically to define the potential entrepreneur and, from an applied perspective, to design training programmes to support future technological entrepreneurs.  相似文献   
189.
Conduct problems are among the most discussed behavioral problems during childhood and adolescence. Given their heterogeneity, in recent years, researchers on this topic have called for delineation of early-onset conduct problems on the basis of affective, interpersonal and behavioral traits that resemble adult psychopathy. The present study aims to analyze, from both a cross-sectional and longitudinal perspective, whether early psychopathic traits allow identification of a group of individuals defined by severe and persistent behavioral problems. To achieve this goal, data from a sample of 192 children (aged 6 to 11) were analyzed; from this sample, 133 children were followed-up in a new data collection that took place three years later. From the data obtained with the mCPS and CBCL (parents), and APSD and TRF (teachers), we observed that children who showed early psychopathic traits, also showed greater frequency, severity and persistence of conduct problems. These results suggest the need to take into account the role of psychopathic traits (particularly, affective and interpersonal) as risk factors to delimit the most serious and persistent patterns of externalizing behavior.  相似文献   
190.
Although homework completion is said to be rather important to achievement, nowadays there is a growing concern of educators about the increasing number of students who do not engage properly on doing the homework tasks and the subsequent impact on school failure rates. Focusing on English as a Foreign Language (EFL) and using a sample of 591 Portuguese fifth and sixth graders, the present study analyses the role played by a number of homework variables on students' achievement (proximal and distal), and their mediating role on the use of self-regulated learning strategies and perceived self-efficacy in the domain. Data confirm the indirect effect of homework on school achievement, by means of the referred cognitive and motivational variables (use of self-regulated learning strategies and self-efficacy). These findings are further discussed in order to highlight the significant role homework completion can play on fighting school failure.  相似文献   
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