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61.
Social Psychology of Education - In Chile, a vast and persistent gender gap in math performance at university admission has negative consequences for women’s opportunities. International...  相似文献   
62.

Given the rise in cyberbullying among secondary education students and the importance of certain psychological adjustment variables for the comprehension of this type of violent behavior, both in bullies and in victims, the purpose of the present study was to analyse the emotional adjustment of those involved in cyber- and traditional bullying. The adjustment variables studied were self-concept, perceived stress, loneliness, depressive symptomatology, social anxiety, life satisfaction, and emotional intelligence. Using a sample of 1318 adolescents (47% boys), aged between 11 and 17 years, four groups were established to compare victims and cybervictims (uninvolved students, traditional victims, cybervictims, and traditional–cybervictims). The analysis of variance showed that students who performed the same role (bully or victim) in both contexts (at school and online). In particular, those who suffered traditional or cyberbullying or both conjointly presented lower scores in physical and social self-concept, life satisfaction, emotional clarity, and emotion regulation, as well as higher scores in perceived stress, loneliness, depression, and social anxiety. In bullies—traditional, cyberbullying or both simultaneously—higher scores were observed in perceived stress, loneliness, depressive symptomatology, fear of negative assessment, avoidance, and general social anxiety, and lower scores in the dimensions of academic and family self-concept, life satisfaction, emotional clarity, and emotion regulation. In general, the findings indicate that students who were involved in bullying situations, both victims and bullies, presented more damaged emotional profiles than those who are uninvolved, especially students who performed the same role (bully or victim) in both contexts (at school and online).

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63.
Animal Cognition - Overmarking remains an unstudied topic in juvenile mammals. We have previously documented a very high rate of overmarking by foals in four captive African equid species: mountain...  相似文献   
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65.
Gutiérrez  G.  de Guzmán  I. P.  Martínez  J.  Ojeda-Aciego  M.  Valverde  A. 《Studia Logica》2002,72(1):85-112
The tree-based data structure of -tree for propositional formulas is introduced in an improved and optimised form. The -trees allow a compact representation for negation normal forms as well as for a number of reduction strategies in order to consider only those occurrences of literals which are relevant for the satisfiability of the input formula. These reduction strategies are divided into two subsets (meaning- and satisfiability-preserving transformations) and can be used to decrease the size of a negation normal form A at (at most) quadratic cost. The reduction strategies are aimed at decreasing the number of required branchings and, therefore, these strategies allow to limit the size of the search space for the SAT problem.  相似文献   
66.
The goal of this study was to determine whether a sensorimotor or cognitive encoding is used to encode a target position and save it into iconic memory. The methodology consisted of disrupting a manual aiming movement to a memorized visual target by displacing the visual field containing the target. The nature of the encoding was inferred from the nature and the size of the errors relative to a control. The target was presented either centrally or in the right periphery. Participants moved their hand from the left to the right of fixation. Black and white vertical stripes covered the whole visual field. The visual field was either stationary throughout the trial or was displaced to the right or left at the extinction of the target or at the start of the hand movement. In the latter case, the displacement of the visual field obviously could only be taken into account by the participant during the gesture. In this condition, our hypothesis was that the aiming error would follow the direction of visual field displacement. Results showed three major effects: (1) Vision of the hand during the gesture improved the final accuracy; (2) visual field displacement produced an underestimation of the target distance only when the hand was not visible during the gesture and was always in the same direction displacement; and (3) the effect of the stationary structured visual field on aiming precision when the hand was not visible depended on the distance to the target. These results suggest that a stationary structured visual field is used to support the memory of the target position. The structured visual field is more critical when the hand is not visible and when the target appears in peripheral rather than central vision. This suggests that aiming depends on memory of the relative peripheral position of the target (allocentric reference). However, in the present task, cognitive encoding does not maintain the "position" of the target in memory without reference to the environment. The systematic effect of the visual field displacement on the manual aiming suggests that the role of environmental reference frames in memory for position is not well understood. Some studies, in particular those of Giesbrecht and Dixon (1999) and Glover and Dixon (2001), suggested differing roles of the environment in the retention of the target position and the control of aiming movements toward the target. The present observations contribute to understanding the mechanism involved in locating and grasping objects with the hand.  相似文献   
67.
A comparative analysis was conducted of five different methods for scoring the Rod-and-Frame Test to examine the convergent validities of each of the five methods with performance on the Embedded Figures Test for a sample of 408 13- to 16-yr.-olds. The scoring methods included the absolute error, the algebraic error, the absolute value of the algebraic error, the frame effect, and an assessment of relative field dependence. Correlations obtained among the five methods and the Embedded Figures Test indicated different patterns for boys and girls. In general, the method which employed the absolute value of the algebraic error yielded the strongest convergent validity coefficients with scores on the Embedded Figures Test and Group Embedded Figures Test for boys (.62 and -.54, respectively), although, for girls, the absolute algebraic error and absolute error both yielded coefficients of .50 with Embedded Figures Test scores and -.46 with Group Embedded Figures Test scores.  相似文献   
68.
We examined whether the functionality of spatial relations affects the construction and memory of information in situation models. A functional relationship involves the interaction of entities that is implied by either typical use or contextual demands. Previous research has shown that spatial relations are less likely to be encoded during comprehension unless there is extensive prior knowledge, explicit instructions to attend to spatial information, or a clear emphasis on spatial information. If the construction of a situation model is guided by a need to understand the functional structure of a situation, then functional spatial relations should be more likely to be encoded. The results of our study showed that sentences with functional spatial relations were read faster and remembered better in both recall and recognition tests than sentences with nonfunctional spatial relations.  相似文献   
69.
Current general health belief measures that are used to assess health behaviors do not capture the full range of health beliefs present among Latinos. The purpose of this study was to develop a reliable and valid measure of Latino health beliefs, the Cultural Health Attributions Questionnaire (CHAQ). Three hundred forty participants were recruited in 2 metropolitan areas with large Latino populations. Exploratory factor analysis revealed 2 highly interpretable 12-item subscales: the Equity Attribution and the Behavioral-Environmental Attribution scales. Examination of the relationships between the subscales and measures of acculturation provided evidence of construct validity. Moreover, the prediction of health care behavior by the CHAQ also indicated initial criterion validity.  相似文献   
70.
The purpose of this study was to identify factors associated with early onset of sexual intercourse. Within an ecological system's conceptual framework, familial factors associated with early onset of sexual activity were identified in a sample of 425 adolescents from San Juan metro area schools. Measures included questions about sexual activity, sexual permissiveness, and such familial variables as: discipline, parental supervision, and parental support. Significant relationships were observed between early onset of sexual intercourse and parental supervision, discipline, parental support, and parents' marital status. Results suggest the key role of parents and family in prevention of HIV-risk behaviors among adolescents in terms of delaying sexual onset. Overall, the study described youths who postponed sexual activity as having greater support, supervision, and parental involvement.  相似文献   
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