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J Feinman

Publications and source records attributed to J Feinman.

11 recordsLinked to original sources
PubMed1995

Development and validation of adolescent-perceived microsystem scales: social support, daily hassles, and involvement.

Developed and validated instruments for urban and culturally diverse adolescents to assess their self-reported transactions with family, peer, school, and neighborhood microsystems for the constructs of social support, daily hassles, and involvement. The sample of 998 youth were from schools in three Eastern cities with high percentages of economically disadvantaged youth. Data were collected before and after the transition to junior high school or to senior high school. Blacks constituted 26%, whites 26%, and Latinos 37% of the sample. Factor analyses confirmed and enhanced the hypothesized four-factor microsystem factor structure for support, hassles, and involvement; internal consistency and stability coefficients were consistent with these structures. In general, the microsystem factors were common across gender, ethnicity, and age. However, when group differences did occur on these demographic variables, they tended to validate the salience of microsystem specificity. In contrast to the total scores, the microsystem-specific factors yielded more meaningful and differential information with regard to demographic differences and the mediating processes across a school transition.

Adolescent↗
PubMed1994

The impact of school transitions in early adolescence on the self-system and perceived social context of poor urban youth.

This study examined the effects of the normative school transition (n = 580) during early adolescence on the self-system and perceived school and peer social contexts of poor, black (n = 161), white (n = 146), and Latino (n = 273) youth in the public school systems of 3 eastern urban cities. The results revealed negative effects of the school transition on the affective and behavioral domains of the self-system. These declines in self-esteem, class preparation, and grade-point average (GPA) were common across race/ethnicity and gender. Concurrently, the school transition was perceived to be associated with changes in the school and peer contexts. Daily hassles with the school increased, while social support and extracurricular involvement decreased over the transition. Daily hassles with peers decreased, and peer values were perceived as more antisocial. These changes in the school and peer microsystems were also common across race/ethnicity and gender. In addition, transition-associated school and peer changes and, in particular, changes in daily hassles with the school were associated with changes in the academic dimensions of the self-system, that is, academic efficacy expectations, class preparation, and GPA. The results are discussed within a developmental mismatch framework.

Adolescent↗
PubMed1982

Cell surface insertion of exogenous epidermal growth factor receptors into receptor- mutant cells: demonstration of insertion in the absence of added fusogenic agents.

We show that epidermal growth factor (EGF) receptor can be transferred in a biologically active orientation from donor hepatic membranes to recipient receptorless fibroblast cells. The recipient cells (NR-6) normally lack EGF receptors and are biologically unresponsive to EGF. The transfer of receptors from donor plasma membranes to recipient NR-6 surface membranes occurs in the absence of any added fusogenic agent. Studies on time and temperature dependence of this transfer indicate that it is due to preferential insertion of the EGF receptor over the other hepatic proteins. The inserted receptor is exceptionally stable to dissociation or damage, and this facilitated studies on its biological properties. The inserted receptor confers upon the hitherto unresponsive variant NR-6 cells a specific biological responsiveness to EGF as measured by EGF-induced stimulation of DNA replication and cell division. These findings suggest the existence of an affinity-mediated mechanism for the biologically active insertion of exogenous EGF receptors into receptorless variant cells. This insertion approach may be of use in the identification of receptor-associated membrane proteins that play a role in the transmission of EGF biological message.

Animals↗