Clemson University

About: Clemson University is a education organization based out in Clemson, South Carolina, United States. It is known for research contribution in the topics: Population & Control theory. The organization has 20556 authors who have published 42518 publications receiving 1170779 citations. The organization is also known as: Clemson Agricultural College of South Carolina.

Toward a cytological characterization of the rice genome

Abstract: Rice (Oryza sativa L.) will be the first major crop, as well as the first monocot plant species, to be completely sequenced. Integration of DNA sequence-based maps with cytological maps will be essential to fully characterize the rice genome. We have isolated a set of 24 chromosomal arm-specific bacterial artificial chromosomes to facilitate rice chromosome identification. A standardized rice karyotype was constructed using meiotic pachytene chromosomes of O. sativa spp. japonica rice var. Nipponbare. This karyotype is anchored by centromere-specific and chromosomal arm-specific cytological landmarks and is fully integrated with the most saturated rice genetic linkage maps in which Nipponbare was used as one of the mapping parents. An ideogram depicting the distribution of heterochromatin in the rice genome was developed based on the patterns of 4',6-diamidino-2-phenylindole staining of the Nipponbare pachytene chromosomes. The majority of the heterochromatin is distributed in the pericentric regions with some rice chromosomes containing a significantly higher proportion of heterochromatin than other chromosomes. We showed that pachytene chromosome-based fluorescence in situ hybridization analysis is the most effective approach to integrate DNA sequences with euchromatic and heterochromatic features.

Black and white females' perceptions of ideal body size and social norms.

Abstract: Different cultural norms and standards for appropriate female body size might contribute to the disparity in obesity rates between black and white adult females (46.0% and 24.6% respectively). The purpose of this study was to measure adolescents' perceptions of ideal size and social norms regarding female body size as well as adolescents' perceptions of significant others' evaluation and expectations of the adolescents' body size. Subjects included 437 adolescent girls (247 white and 190 black) aged 13 to 19 (x = 14.9, SD = .979) from six randomly selected public schools. The subjects, heights and weights were measured. Responses to a body image questionnaire and a series of nine female body drawings (arranged ordinally, 1 to 9, from thinnest to heaviest) were analyzed using the General Linear Model and Logistic Regression. The female body size considered ideal by black females was significantly larger than the size selected as ideal by white females (x = 3.47 and x = 3.13 respectively, p < 0.001). Black females were two times more likely than white females to describe themselves as thinner than other girls their age (O.R. = 2.01, 95% C.I. 1.34, 3.01) and seven times as likely to say that they were not overweight (O.R. = 7.08, 95% C.I. 3.72, 13.45). White females wanted to be a smaller size than they currently were and felt encouraged by significant others to lose weight or reduce their size. Black females did not indicate as great a desire as whites to be smaller and they tended to feel that their size was considered satisfactory by significant others. Only subjects from the low SES group perceived that significant others wanted them to gain weight. The differences between black and white subjects' beliefs and perceptions about body size norms may explain, in part, why heavier body weights persist in some cultural groups.

An economic analysis of the timing of childbirth

Abstract: Summary In this paper we present a new ‘home economics’ model of the timing of the first birth. The child-timing decision is treated as a multi-period planning problem in which the date of first birth influences both the mean and the dispersion of the household's intertemporal income distribution. Couples are assumed to use capital markets and the timing of childbirth to smooth life-cycle consumption. Optimal timing is shown to depend upon the rate at which job skills depreciate during unemployment, the wife's pre-marital work experience, the opportunity costs of completing a family, and the mean and dispersion of the husband's intertemporal earnings profile. The theory is tested with statistics drawn from the National Longitudinal Surveys. The results strongly support those theoretical hypotheses that can be tested and offer insights into timing patterns. If the upsurge in women's labour force participation and educational involvement continue, our work implies that there will be a marked economic incent...