Dexter C. Whittinghill

Assimilation of carbon and nitrogen from pollen and nectar by a predaceous larva and its effects on growth and development

Abstract.  1. Predaceous insects may benefit from feeding on non‐prey foods, such as pollen, nectar, and honeydew, because they can provide nutrients that help maintain metabolism and enhance overall nutrient intake. Yet, the extent to which predaceous insects can assimilate non‐prey food and the importance of diet mixing during particular life history stages is poorly understood. In this study the relative contribution of an omnivorous diet to the growth and survivorship of a predaceous larva was tested in a hypothetical situation in which nutritionally optimal prey was not available. The study system comprised a predaceous larva (second‐ and third‐instar larvae of the green lacewing Chrysoperla carnea), nutritionally poor prey (larvae of Drosophila melanogaster), and non‐prey food (pollen suspension, a mixture of bee pollen and artificial nectar (1 M sucrose solution)). Chrysoperla carnea larvae in the mixed diet treatment were provided with both Drosophila larvae and pollen suspension, while those reared on the prey and non‐prey diet treatments received only Drosophila larvae or pollen suspension respectively.

A note on the robustness of Box-Behnken designs to the unavailability of data

Abstract. Box-Behnken designs and central composite designs are efficient designs for fitting second order polynomials to response surfaces, because they use relatively small numbers of observations to estimate the parameters. In this paper we investigate the robustness of Box-Behnken designs to the unavailability of observations, in the sense of finding tmax, the maximum number of arbitrary rows in the design matrix that can be removed and still leave all of the parameters of interest estimable. The results are compared to the known results for the central composite designs found in MacEachern, Notz, Whittinghill & Zhu (1995). The blocked Box-Behnken designs are equally as robust as those that are not blocked.

The impact of a living learning community on first-year engineering students

The purpose of this study was to investigate the impact of an engineering living and learning community (ELC) on first-year engineering students. A control group of non-ELC students was used to compare the experiences of the ELC participants. Analysis of survey data showed that there was significant differences between the ELC students and the non-ELC students in how they responded to questions regarding social support, academic support, connectedness to campus, and satisfaction with the College of Engineering and the institution as a whole. Particularly, there were significant differences between ELC and non-ELC students for questions related to feeling like part of an engineering community, having strong relationships with peers, belonging to a supportive peer network, studying with engineering peers, and spending time with classmates outside of class.

Providing Rapid Feedback to Students to Improve Student Learning and Engagement

In this project our goal is to improve student learning in engineering mechanics courses. The aim to improve learning was accomplished by providing rapid feedback to students of their understanding of key concepts and skills being taught. The feedback system acts as a catalyst to encourage students, working in pairs, to assist each other in correcting misconceptions or deepening each other’s understanding of the concept or skill at hand. Furthermore, the system allows the professor to assess the students’ level of comprehension or misconception in a just-in-time fashion, and thus guide the pace of covering the material. The feedback is enabled through wireless-networked handheld computers or color-coded flashcards. In the first two years of the study, the feedback system was implemented in two sections of a lower-level, core-engineering course, Statics, as well as in follow-on courses of Dynamics and Solid Mechanics.Copyright