A multivariate analysis of the factors affecting the retention of first and second term Air Force enlisted members.

The purpose of this thesis was to identify the factors influencing voluntary retention behavior of first and second terra Air Force enlisted members. Further, how those factors tended to differ across term of service and occupational group was examined. Data were extracted from the 1985 DOD Survey of Officer and Enlisted Personnel. Explanatory variables were grouped into tenure, demographic, cognitive, and economic categories. Logit models were estimated for each term of service and occupational sub group. The results show that the factors affecting retention do tend to differ across term and occupation. Some, like overall satisfaction, were significant to everyone, while others, such as SRB, changed from one group to the next. Recommendations regarding future policy implications were made along with several recommendations for future research.http://archive.org/details/multivariateanal00lempFirst Lieutenant, United States Air ForceApproved for public release; distribution is unlimited

Progress and Promise in using Arabidopsis to Study Adaptation, Divergence, and Speciation

Fundamental questions remain to be answered on how lineages split and new species form. The Arabidopsis genus, with several increasingly well characterized species closely related to the model system A. thaliana, provides a rare opportunity to address key questions in speciation research. Arabidopsis species, and in some cases populations within a species, vary considerably in their habitat preferences, adaptations to local environments, mating system, life history strategy, genome structure and chromosome number. These differences provide numerous open doors for understanding the role these factors play in population divergence and how they may cause barriers to arise among nascent species. Molecular tools available in A. thaliana are widely applicable to its relatives, and together with modern comparative genomic approaches they will provide new and increasingly mechanistic insights into the processes underpinning lineage divergence and speciation. We will discuss recent progress in understanding the molecular basis of local adaptation, reproductive isolation and genetic incompatibility, focusing on work utilizing the Arabidopsis genus, and will highlight several areas in which additional research will provide meaningful insights into adaptation and speciation processes in this genus