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Lacking both alleles of the tumor suppressor gene p53 results in the lethality of a subset of 129 female mice (16%) in early embryogenesis due to exencephaly. In this study we show that novel genetic modifier genes of p53 can exacerbate embryonic abnormalities. Using a mouse model in which CE mice were crossed with the p53-null 129 mice, a subset of p53+/- and -/- male and female embryos died during gestation. Our hypothesis based on the skewed ratio from Mendellian inheritance in the F2 generation is two genetic modifiers of a p53 null allele lead to an increase in embryonic lethality. We have identified a recessive modifier of the p53 (mop1) locus from CE mice on chromosome 11 centromeric to p53, and a dominant modifier of p53 (mop2) locus from 129 mice on chromosome 11 telomeric to p53. Sequencing of candidate genes within these two regions revealed a transverse mutation (321P to 321S) in the Ovca1 gene within the mop2 locus of CE mice. The mutation increased both mRNA and protein levels of Ovca1 in various tissues in CE mice compared to 129 mice. CE primary cells cultured from different tissues proliferated more rapidly than 129 cells. In addition, CE cells were in G1, S, and G2/M phases while 129 cells have a higher percentage in the G1 phase. Transfection of wild-type Ovca1 into CE cells caused a higher G1 phase arrest. OVCA1 protein localized to punctate bodies clustered around the nucleus in CE mice, while in 129 mice OVCA1 was diffused throughout the cell. Immunohistochemical staining showed that p53+/- abnormal embryos have more proliferating cells than normal embryos, but no obvious difference was observed in differentiated neuronal cells and apoptotic cells. p53-/- small embryos have less differentiated neuronal cells and proliferating cells as well as more apoptotic cells than the normal embryos. Normal and abnormal p53+/- F2 embryos both have the Ovca1 mutation. Thus, Ovca1 combined with mop1, genetically modifies embryonic lethality in p53 deficient mice.

In this dissertation, we investigate optimal control of partial differential equations. We prove the existence of optimal controls for which the objective functional are minimized or maximized. The goal is to characterize the optimal control in terms of the solution of the optimality system. The optimality system consists of the state equations coupled with the adjoint equations. To obtain the optimality system we differentiate the objective functional with respect to the control. This process is applied to studying a predator-prey parabolic system with Robin boundary condition, to control the effects of boundary habitat hostility. In a wave equation problem, a bilinear control is used to bring the state solution close to a desired profile under a quadratic cost control. We also establish the uniqueness of the solution of the optimality system and thus determine the unique optimal control. In the problem of a wave equation with viscous damping, we control the damping term. We seek to minimize the cost functional which measures the closeness of state solutions to a desired profile.

Very little literature has evaluated the efficacy of conservation strategies for controlling migrant bird poaching in the world's protected areas. This study reflects a program evaluation which was conducted in the Kenting National Park, Taiwan, using Action Research process to protect two fall migrant birds in flyways of Eastern Asia: gray-faced buzzard-eagle and brown shrike from being poached on cultivated lands in the Hengchun Peninsula. This research examines the policing, school education and village advocacy, and diagnoses the deficiencies in policy and program planning, target response, and program delivery. Evaluability Assessment, Conflict Assessment, Needs Assessment, Management lnformation System, Field Observation, Interview and Survey were supplementary methods used to strengthen research validity. The program's problems are rooted in its prohibitive hunting policy content, centralized planning process and the negligence of the program preparation. The policies were made to comply with global interests, the mandates of two former presidents' wildlife hunting ban, and national park development. The park's policing, inculcation, incentive and media approach have a positive impact on saving birds and stopping international trade, but are too weak to promote social and value change. Many social actions and new poaching strategies were merged to confront the park. Both students' and adults' poaching of protected birds still prevail in the target area in the last ten-year program period. Rangers, educators and village elites suggest that the park enhances participation and communication, and improves resources for program implementation. This study recommends that the park reverse its stigmatization media, promote value analysis and ecotourism, raise grassroots assets, revise program policy, restore habitat, and solve community problems first to release the emerging conflict. The research methods contributed to the implementation of both program and evaluation process, corrected the group biases, transferred the evaluation technologies to participants and increased the utility of the findings. Because the program is frequently in conflict with the social and economic development of indigenous societies, evaluators should be interdisciplinary, familiar with group process, sensitive to the politics and cultures in the program environment, take a global and long-term perspective, select multiple methods critically and creatively, and interpret research finding ethically.