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51.
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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The purposes of the present study were threefold: (a) to assess the prevalence levels of anxiety and depression in a sample of Mexican migrant farm workers in the midwestern United States; (b) to explore the relationships among acculturative stress, anxiety, and depression; and (c) to examine the variables that best predict anxiety and depression. The overall sample revealed elevated levels of anxiety and depression. Migrant farm workers with heightened levels of acculturative stress were more likely to report high levels of anxiety and depression. Family dysfunction, ineffective social support, low self-esteem, lack of agreement with the decision to migrate, high education levels, high levels of acculturative stress, and high levels of anxiety were significantly associated with high depression levels. The overall findings suggest that migrant farm workers who experience elevated levels of acculturative stress may be at risk for experiencing high levels of anxiety and depression. The findings highlight the importance of establishing prevention and treatment services for migrant farm workers that aim to increase levels of emotional support, self-esteem, and coping skills.  相似文献   
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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   
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This study examined predictors of anxiety symptomatology among immigrant Mexican migrant farmworkers in the Midwest. Its purposes were to assess the prevalence of anxiety symptoms, to examine the relationship between acculturative stress and anxiety, and to determine the variables that best predict anxiety. Heightened levels were found for overall anxiety and in the cognitive, affective, and physiological expressions of anxiety. Elevated acculturative stress, low self-esteem, ineffective social support, lack of control and choice in living a migrant farmworker lifestyle, low religiosity, and high education were significantly related to high anxiety. Findings suggest that migrant farmworkers who experience elevated acculturative stress are susceptible to the development of anxiety-related disorders and highlight the importance of establishing prevention and treatment services for migrant farmworkers.  相似文献   
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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   
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