Effective Genericity and Differentiability

We prove that a real x is 1-generic if and only if every differentiable computable function has continuous derivative at x. This provides a counterpart to recent results connecting effective notions of randomness with differentiability. We also consider multiply differentiable computable functions and polynomial time computable functions.Comment: Revision: added sections 6-8; minor correction

Calvinisme en de kunst

Rectorale oratie Vrije Universiteit 188

An investigation of career development by Community College and University women : importance of contributors to advancement into higher education administration

Surveys of women in higher education administrative positions that identified factors which may contribute to career development have been conducted. However, the literature revealed little information regarding the importance placed on those factors by women in higher education administrative positions. The purpose of this study was to determine the importance of selected contributors to career development of women in higher education administration. Data were gathered by a mailed questionnaire to a sample of women administrators employed in Florida state supported community colleges and universities. The 343 useable returned questionnaires represented a 65.5% response rate and 51.3% of the total population. These data were evaluated in terms of: a) the factors identified by women, b) race and age, c) administrative level by institution type, and d) institution type. Descriptive data analysis was conducted using frequency distributions and histograms. Cross tabulation analysis with all statistical options and a one-way analysis of variance were also utilized. There were four factors considered important for which there were no significant differences across the variables of institution type, administrative level by institution type, and selected demographic characteristics. These factors were formal education, willingness to accept added responsibility, timing, and communication skills. The contributing factors showing importance by administrative level by institution type were: chance, participation in a formal administrative internship, committee appointments, and teaching experience. Those factors viewed as important by institution type were: willingness to relocate (community college) and research and publications (university). The factors considered important by age were: a) Affirmative Action plans, b) influence of a mentor, c) personnel administration skills, d) participation in a formal administrative internship, and e) research. The results of the study indicated that women desiring to advance into higher education administrative positions should develop a career plan to include the institution type desired for career development. In addition, women should give serious consideration to the four factors showing no significant difference by institution type, or by selected demographic characteristics

Breeding for improved responsiveness to arbuscular mycorrhizal fungi in onion

Arbuscular mycorrhizal fungi (AMF) play an important role in the uptake of nutrients and water from soil. Onions, Allium cepa L., are plants with a shallow root system. As a result, onion plants need a lot of fertiziler for their growth. Furthermore, onion plants are sensitive to drought. The aim of the current research project is to study the beneficial effect of mycorrhizal fungi on the growth and development of Allium species and to determine whether it is possible to improve onions for mycorrhizal responsiveness by means of breeding. Variation among Allium species and segregation observed in a interspecific tri-hybrid population indicate that selection and thus breeding for high responsiveness to AMF is possible

Evolutie

Rectorale oratie Vrije Universiteit 189

De verflauwing der grenzen

Rectorale oratie Vrije Universiteit 189

Multi-Level Risk and Protective Factors for Substance Use among Zambian Street Youth

Background: High rates of substance use have been reported among youth in Zambia. This is particularly concerning given that substance use is one of the biggest risk factors placing young people at risk for HIV infection. Objectives: The purpose of the current study is to examine how multilevel risk and protective factors (i.e., community, family, peers, individual) influence alcohol and marijuana use. Methods: A total of 250 street youth in Lusaka, Zambia, were interviewed in the summer of 2014 about their alcohol and marijuana use and reasons for usage. Data were analyzed using descriptive and multivariate methods. Results: Youth reported high rates of alcohol use. At the multivariate level, peer- and individual-level variables (e.g., using alcohol or drugs for coping or for fun) explained the most variance, followed by family-level factors. Community-level variables explained the least variance in all models. Conclusion/Importance: A better understanding of multilevel risk and protective factors for young people’s alcohol and marijuana use could lead to the development of better intervention strategies to reduce this behavior among Zambian street youth