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Biomedical subjects

J L Newman

Publications and source records attributed to J L Newman.

26 records · Page 2Linked to original sources
PubMed1984

A hazard rate approach to the timing of births.

"This paper discusses two approaches that economists have taken in analyzing the timing of births. It formulates an empirical model appropriate for one of these approaches and demonstrates its usefulness using household survey data from Costa Rica. The hazard rate technique employed in this paper is a natural way of modeling a broad class of problems where the occurrence of an event is uncertain." The study also indicates that "historical data can be used to determine whether the strong trend in the relationship between regional mortality levels and the age at first birth is real or the result of inappropriate data. Additionally, data from other countries might be employed to determine whether the significant effect of male education levels on the risk of subsequent births is a general result. Finally..., the predictions of theoretical models dealing with the number and pace of births can be tested using data from younger women."

Age Factors↗
PubMed1983

Do sex-role appropriate materials influence the Piagetian task performance of older adults?

The intent of this study was to assess the influence of sex-role appropriate materials on the utilization of logical competence among older persons, and to determine how such materials interact with subject's sex-role identity to affect cognitive performance. Thirty male and 30 female Ss (mean age = 71.3 years) were administered the Short Form of the Bem Sex-Role Inventory and either a male-oriented, a female-oriented, or a traditional version of two concrete operational and two formal operational Piagetian tasks. Gender was found to influence performance on one of the concrete tasks, task orientation influenced performance on one of the formal tasks, and sex-role classification interacted with task orientation to influence performance on both of the formal operational tasks. The pattern of results suggested that subjects may perform best on those versions of the formal operational tasks that do not match their own sex type. Possible explanations for these findings are discussed.

Aged↗
PubMed1980

Calorimetric studies of lipid phase transitions in native and heat-denatured membranes of beef heart submitochondrial particles.

The lipids in beef heart submitochondrial particles undergo a broad reversible endothermic phase change centered at about -10 degrees C. Following protein denaturation, a new reversible transition centered at about 20 degrees C appears. The extracted lipids from these membranes exhibit thermal behavior that is essentially identical to the lipid transition in the intact membrane after protein denaturation. A role for this latent pool of higher-melting lipids is proposed.

Animals↗