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101.
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   
102.
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   
103.
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   
104.
We examined the associations between parental educational/occupational levels and cognitive performance in Spanish adolescents. Cognitive performance was measured by a validated Scholar Aptitudes test in 2,162 participants. Parental educational and occupational levels were positively associated with all specific cognitive abilities and the overall score (p<001 to .04). The odds ratios of having a high cognitive performance (top quartile) in adolescents with high parental educational level were 1.6 to 1.7 times higher than for those with a low parental educational level. Similarly, the odds ratios were 1.9 to 2.4 times higher for adolescents with high parental occupational level. These findings suggest an association between parental educational/occupational levels and cognitive performance in Spanish adolescents and support the parents' role in the creation of a stimulating intellectual environment.  相似文献   
105.
Psychological interventions in cocaine dependent patients have demonstrated efficacy. Remarkable approaches are Contingency Management (CM) and Cognitive Behavioral Therapy (CBT). Lack of treatment adherence is the most important limitation. Motivational Interview (MI) has been shown to be an adherence enhancer. The objective of this study is to evaluate retention and abstinence in a combined CM and CBT group treatment in patients who have reached maintenance stage according to Prochaska and DiClemente's transtheoretical model (1982). Therefore, a longitudinal study was carried out with cocaine dependent patients with or without concomitant mental health disease. A 12-session open group was conducted weekly. Nineteen patients were included (78.9% men, mean age 36.6 years), 95% consumed intranasally and 47% had another psychiatric comorbidity. Treatment retention was 84%. During treatment and the first month of follow-up, all patients remained abstinent whereas at three months, 3 patients relapsed. These data confirm that using combined CM and CBT group therapy in cocaine dependents undergoing maintenance treatment enhances adherence and is effective to achieve abstinence.  相似文献   
106.
This paper describes the development of a self-report scale for adolescents to assess positive youth development values. It presents a substantial number of psychometric results performed on a sample of 2,400 adolescents (1,068 boys and 1,332 girls) from 12 to 17 years ( M = 14.73, SD = 1.25), who were studying secondary education in Western Andalusia. The results provide evidence of the psychometric quality of items, cross-validity of a structure of eight first-order factors and three second-order factors, obtained through exploratory and confirmatory factor analysis, and adequate reliability. This study concludes that the scale presents adequate evidence of validity and reliability that allows assessment, especially in school contexts, of a broad set of values of particular relevance to positive youth development.  相似文献   
107.
Exposure to severe air pollution produces neuroinflammation and structural brain alterations in children. We tested whether patterns of brain growth, cognitive deficits and white matter hyperintensities (WMH) are associated with exposures to severe air pollution. Baseline and 1 year follow-up measurements of global and regional brain MRI volumes, cognitive abilities (Wechsler Intelligence Scale for Children-Revised, WISC-R), and serum inflammatory mediators were collected in 20 Mexico City (MC) children (10 with white matter hyperintensities, WMH+, and 10 without, WMH) and 10 matched controls (CTL) from a low polluted city. There were significant differences in white matter volumes between CTL and MC children - both WMH+ and WMH - in right parietal and bilateral temporal areas. Both WMH and WMH+ MC children showed progressive deficits, compared to CTL children, on the WISC-R Vocabulary and Digit Span subtests. The cognitive deficits in highly exposed children match the localization of the volumetric differences detected over the 1 year follow-up, since the deficits observed are consistent with impairment of parietal and temporal lobe functions. Regardless of the presence of prefrontal WMH, Mexico City children performed more poorly across a variety of cognitive tests, compared to CTL children, thus WMH+ is likely only partially identifying underlying white matter pathology. Together these findings reveal that exposure to air pollution may perturb the trajectory of cerebral development and result in cognitive deficits during childhood.  相似文献   
108.
The aims of the present study were to assess the psychometric properties of the Spanish-language version of the abbreviated Day Reconstruction Method (DRM), and to investigate differences in affective experience in Mexico and Spain. A total of 2,629 adults from Mexico and 4,583 from Spain were interviewed. Information was obtained using an abbreviated version of the DRM, which had been translated into Spanish. Reliability, validity, and the structure of affect were assessed and compared between countries. The diurnal variation of affect, the changes in affect along the life span, time use, and the relationship between affect and socio-demographic characteristics were also analysed. Adequate psychometric properties for the Spanish-language version of the abbreviated DRM were found in both the Mexican and the Spanish samples, and affect tended to improve along the life span in both countries. However, net affect did not have the same distribution function (Kolmogorov–Smirnov statistic = 0.25, p < 0.001) in both countries, being higher in Spain. Moreover, both samples showed opposite patterns in the diurnal variation of affect. The results showed that the Spanish-language version of the DRM is a feasible and valid method to measure affect, its diurnal rhythms, and time use in large-scale surveys.  相似文献   
109.
This study investigated whether dogs would engage in social interactions with an unfamiliar robot, utilize the communicative signals it provides and to examine whether the level of sociality shown by the robot affects the dogs’ performance. We hypothesized that dogs would react to the communicative signals of a robot more successfully if the robot showed interactive social behaviour in general (towards both humans and dogs) than if it behaved in a machinelike, asocial way. The experiment consisted of an interactive phase followed by a pointing session, both with a human and a robotic experimenter. In the interaction phase, dogs witnessed a 6-min interaction episode between the owner and a human experimenter and another 6-min interaction episode between the owner and the robot. Each interaction episode was followed by the pointing phase in which the human/robot experimenter indicated the location of hidden food by using pointing gestures (two-way choice test). The results showed that in the interaction phase, the dogs’ behaviour towards the robot was affected by the differential exposure. Dogs spent more time staying near the robot experimenter as compared to the human experimenter, with this difference being even more pronounced when the robot behaved socially. Similarly, dogs spent more time gazing at the head of the robot experimenter when the situation was social. Dogs achieved a significantly lower level of performance (finding the hidden food) with the pointing robot than with the pointing human; however, separate analysis of the robot sessions suggested that gestures of the socially behaving robot were easier for the dogs to comprehend than gestures of the asocially behaving robot. Thus, the level of sociality shown by the robot was not enough to elicit the same set of social behaviours from the dogs as was possible with humans, although sociality had a positive effect on dog–robot interactions.  相似文献   
110.
Although gaze-following abilities have been demonstrated in a wide range of species, so far no clear evidence has been available for dogs. In the current study, we examined whether dogs follow human gaze behind an opaque barrier in two different contexts, in a foraging situation and in a non-foraging situation (food involved vs. food not involved in the situation). We assumed that dogs will spontaneously follow the human gaze and that the foraging context will have a positive effect on dogs’ gaze-following behaviour by causing an expectation in the dogs that food might be hidden somewhere in the room and might be communicated by the experimenter. This expectation presumably positively affects their motivational and attentional state. Here, we report that dogs show evidence of spontaneous gaze-following behind barriers in both situations. According to our findings, the dogs gazed earlier at the barrier in the indicated direction in both contexts. However, as we expected, the context also has some effect on dogs’ gaze-following behaviour, as more dogs gazed behind the barrier in the indicated direction in the foraging situation. The present results also support the idea that gaze-following is a characteristic skill in mammals which may more easily emerge in certain functional contexts.  相似文献   
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