Motivation in physical education is correlated with participation in sport after school.

The aim of the present study was to examine differences in motivation with respect to physical education of students who participate in after-school sport clubs and students who do not. 247 secondary school students responded to scales assessing intrinsic motivation, outcome expectancies, perceived competence, and perceived usefulness of physical education. Analysis showed that students in after-school sports exhibited a more positive motivational pattern regarding physical education with intrinsic motivation, outcome expectancies, and perceived competence making unique contributions to the overall difference.

Aspects of self-concept and their relationship to language performance and verbal reasoning ability.

It has been claimed that self-concept is multidimensional, with dimensions such as mathematical self-concept and self-concept in language. The present study investigated the relationship of academic self-concept in language with performance on school-related language tasks and verbal reasoning ability. A total of 512 students in grades 7, 9, and 11 rated four aspects of their academic self-concept in language: self-perception, self-efficacy, self-esteem, and others' perception of their abilities. Verbal reasoning ability and performance on language tasks were assessed. Path analysis showed that performance on language tasks was influenced strongly by verbal reasoning abilities. Self-esteem and others' perception of one's abilities were affected directly by language performance. No direct relationship was found between academic self-concept in language and verbal reasoning ability. The results suggest that adolescents do not construe their academic self-concept according to their abilities but according to their performance in school and others' response to it.

Kappa1-opioid binding sites are the dominant opioid binding sites in surgical specimens of human pheochromocytomas and in a human pheochromocytoma (KAT45) cell line.

The adrenal medulla produces opioids which exert paracrine effects on adrenal cortical and chromaffin cells and on adrenal splanchnic nerves, via specific binding sites. The opioid binding sites in the adrenals are detectable mainly in the medullary part of it and differ in type between species. Thus, the bovine adrenal medulla contains mostly kappa-opioid binding sites and fewer delta- and mu-opioid binding sites while primate adrenals contain mainly delta sites and few kappa-opioid binding sites. Most chromaffin cell tumors, the pheochromocytomas, produce opioids which suppress catecholamine production by the tumor. The aim of the present work was to identify the types of opioid binding sites in human pheochromocytomas. For this purpose, we characterized the opioid binding sites on crude membrane fractions prepared from 14 surgically excised pheohromocytomas and on whole KAT45 cells, a recently characterized human pheochromocytoma cell line. Our data showed that human pheohromocytomas are heterogeneous, as expected, with regard to the production of catecholamines and the distribution and profile of their opioid binding sites. Indeed, only one out of the 14 pheochromocytomas expressed exclusively delta and mu opioid sites, while in the remaining 13 tumors kappa-type binding sites were dominant. The KAT45 cell line possessed a significant number of kappa1 binding sites, fewer kappa2-opioid binding sites and kappa3-opioid binding sites, and minimal binding capacity for delta- and mu-opioid receptor agonists sites. More specifically, the kappa1 sites/cell were approximately 18,000, the kappa2 4500/cell and the kappa3 sites 2000/cell. Our findings for the surgical specimens and the cell line combined with previously published pharmacological data obtained from KAT45 cells suggest that kappa sites appear to be the most prevalent opioid binding sites in pheochromocytomas. Finally, in normal bovine adrenals the profile of opioid binding sites differs in adrenaline and noradrenaline producing chromaffin cells. To test the hypothesis that the type of catecholamine produced by a pheochromocytoma depends on its cell of origin, we compared our binding data with the catecholamine content of each pheochromocytoma examined. We found no correlation between the type of the predominant catecholamine produced and the opioid binding profile of each tumor suggesting that this hypothesis may not be valid.