The Effects of Mathematics Placement on Successful Completion of an Engineering Degree and how One Student Beat the Odds

This dissertation comprises a sequential explanatory mixed methods study seeking to understand persistence in engineering based on a student’s initial mathematics course and the experience of a student who began in the lowest level mathematics course and completed an engineering degree despite struggling in mathematics courses. The first phase of the quantitative piece examines one year retention rates for first year engineering students based on initial mathematics course. In the second quantitative phase a stepwise logistic regression model was conducted to determine what factors are related to engineering persistence. The third quantitative phase is a retrospective study to determine the initial mathematics course for graduating engineering students. The final phase of the quantitative piece examines graduation rates for first year engineering students based on initial mathematics course. Results of the first phase indicate engineering students starting in non-college level mathematics courses are significantly less likely to be retained in engineering a year after their first semester compared to students starting in one of the calculus courses. In the logistic regression model with initial math course, grade in the initial math course, gender and race as predictor variables, course, grade, and gender were found to significantly predict retention in engineering one year later. Results from the third phase indicate very few students graduating with an engineering degree start in precalculus. It also shows some engineering disciplines may be more attainable for students starting in non-college level mathematics courses, like precalculus. Results of graduation rates in the fourth quantitative phase confirm engineering students starting in precalculus are significantly less likely to graduate with an engineering degree than those starting in any higher level mathematics course. A case study was conducted to fully explain how a student persisted in engineering after starting in precalculus. One of the few students starting in precalculus who graduated with an engineering degree was interviewed to understand why he chose engineering, why he didn’t quit or change majors when he had to repeat calculus II multiple times, and how he was able to complete his calculus courses despite his mathematical deficiencies. Other individuals who he indicated were influential in his success were also interviewed. A framework combining future time perspective and self-regulation was used to explain his experience and why he didn’t quit. Another framework on self-regulated learning strategies was used to explain how he was able to successfully complete calculus II. The case study student’s dream of becoming a pilot in the Air Force and his ‘can’t quit’ attitude were the motivation for his persistence in engineering. An instruc-tor in the Mathematical Sciences Department and the instructor’s ability to model self-regulation strategies were instrumental in the student’s eventual completion of an engineering degree. By understanding the experience of one of the few successful engi-neering students who started in a non-college level mathematics course, educators can better advise future students with similarly poor mathematics backgrounds

The aryl hydrocarbon receptor instructs the immunomodulatory profile of a subset of Clec4a4

SignificanceEosinophils contribute to type 2 immunity against helminths and allergens. The small intestine harbors eosinophils with incompletely understood pathophysiological roles. Here, we show that intestinal eosinophils include two subsets. One expresses the inhibitory receptor Clec4a4 and the inhibitory ligand PD-L1 and is unique to the small intestine; the other manifests a proinflammatory phenotype. Both subsets are blood derived. Remarkably, Clec4a