A systematic analysis of parthenogenetic (PG) cell fate within the central nervous system (CNS) was made throughout fetal development and neonatal and adult life. Chimeras were made between PG embryos carrying a ubiquitously expressed lacZ transgene and normal fertilized embryos. After detailed histological analysis, we find that the developmental potential of PG cells is spatially restricted to certain parts of the brain. PG cells are prevalent in telencephalic structures and are largely excluded from diencephalic structures, especially the hypothalamus. These spatial restrictions are established early in development. Behavioral studies with chimeras identified an increase in male aggression when the proportion of PG cells in the brain was high. These studies demonstrate that imprinted genes play key roles in development of the CNS and may be involved in behavior.

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A status survey design with mixed groups was employed to investigate the effects of the positive Action self-concept program on the self-esteem of fourth, fifth, and sixth graders. The Positive Action group had been exposed to the self-concept enhancement program by the classroom teachers as a part of the curriculum. Students had had the instruction for a period of one to four years, depending on the number of years of attendance at that particular school. The control group had had no exposure to the program. The independent variables investigated were participation or nonparticipation in the program, grade placement, length of time in the program, reading level and gender. The dependent variables were general self, social self-peers, home-parents, school-academic and total self scores, all of which are components of the Coopersmith Self-Esteem Inventory. Data analysis consisted of testing four null hypotheses. The hypotheses were tested employing a one-way analysis of covariance, a one -way analysis of variance and a three-way analysis of variance. A total of 65 comparisons were made, 3 of which were found to be statistically significant. The results of this study appeared to support the following generalizations: 1. fourth grade students who experienced the Positive Action program had lower self-esteem than those who had not experienced the program; 2. sixth-grade students who experienced the positive Action program had lower self- esteem concerning school than those who had not had the program; 3. girls had a higher self-esteem during the first two years of participation in the positive Action program but as the program progressed, boys increased in self-esteem and after three years participation had a higher self-esteem than girls.