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Professional development (PD) workshops designed to help faculty move from teacher- to learner-centered science courses for undergraduates are typically evaluated with self-reported surveys that address faculty's satisfaction with a workshop, what they learned, and what they applied in the classroom. Professional development outcomes are seldom evaluated through analysis of observed teaching practices. We analyzed videotapes of biology faculty teaching following PD to address three questions: (1) How learner centered was their teaching? (2) Did self-reported data about faculty teaching differ from the data from independent observers? (3) What variables predict teaching practices by faculty? Following PD, 89% of the respondents stated that they made changes in their courses that included active, learner-centered instruction. In contrast, observational data showed that participation in PD did not result in learner-centered teaching. The majority of faculty (75%) used lecture-based, teacher-centered pedagogy, showing a clear disconnect between faculty's perceptions of their teaching and their actual practices.

Understanding the cost of immune function is essential for more accurate characterization of energy budgets of animals and better understanding of the role of immunity in the evolution of life‐history strategies. We examined the energetic cost of maintaining a normally functioning immune system and mounting a mild immune response in wild male white‐footed mice (Peromyscus leucopus). To evaluate the cost of maintaining immunocompetence, we compared resting and daily metabolic rates (RMR; DMR) and masses of body organs of mice whose immune systems were suppressed by cyclophosphamide with those of control mice. To evaluate the cost of mounting an immune response, we measured RMR, DMR, and organ masses in mice whose humoral and cell‐mediated immune responses had been stimulated by injections of sheep red blood cells and phytohemagglutinin, respectively. Immunosuppression resulted in a significant reduction in circulating leukocytes, by 225%, but no significant effect on metabolic rates or organ masses. Immunochallenged animals showed no significant differences in metabolic rates compared with control animals but did exhibit significantly smaller dry masses of the small intestine and testes, by 74% and 22%, respectively. We concluded that the cost of maintaining the immune system was minimal. In contrast, there was a significant energetic cost of mounting an immune response that, depending on its magnitude, can be met through reductions in energy allocation to other physiological systems.

A number of studies have suggested the incompatibility of simultaneous increases in immune and reproductive functions. Other research has indicated that immune responses may be modulated depending on the relative benefits of increased survival and prospects for current and future reproduction. We tested the hypothesis that energy allocation to reproductive and other organ systems is not affected by testosterone level and energy expenditure on immune functions. Adult male white-footed mice (Peromyscus leucopus) with or without elevated testosterone levels and with or without immunochallenges were tested. Testosterone treatment was associated with reduced humoral immune response indicating immunosuppressive effects, reduced masses of gastrointestinal organs, reduced corticosterone level, increased kidney and seminal vesicle masses, and increased hematocrit. Immunochallenge was associated with increased resting metabolic rate and testes and seminal vesicle masses. Reproductive organ masses were greatest in immunochallenged mice with exogenous testosterone. Simultaneous increases in energy allocation to immune and reproductive structures may be an adaptive response that would enhance survival and current prospects for reproduction.

To understand the importance of plasticity of central processing organs (i.e., stomach and intestinal organs) to animals in the wild, field studies of changes in organs and their relationships with variable environmental conditions and energy demands are needed. We determined relationships among diet quality, indicators of energy demand, sizes of central processing organs, and rate of nutrient uptake in free-living white-footed mice (Peromyscus leucopus) in western Kentucky. Moderate winters and dry summers characterized the study site. In contrast to studies conducted in more extreme environments, we found limited differences in the sizes and function of central processing organs among seasons. Masses, but not lengths of intestinal organs or the rate of glucose uptake, differed among seasons. Heart and spleen masses, but not masses of the lungs, kidneys, or liver, also differed among seasons. Differences in the amount of food ingested and percentage of protein in the diet were likely contributors to seasonal differences in intestinal organ masses. Lactation was associated with heavier masses of all central processing organs and increased rate of glucose uptake, but not with heavier masses of vital organs. Greater size and function of intestinal organs during lactation was attributed primarily to high energy demand and secondarily to diet. We postulated that large changes in size and function of central processing organs in free-living mammals occur during intense, but not moderate, changes in energy demand and diet composition and are dependent on the type of energy demand incurred.

Our research objective was to determine if animal-assisted activities (AAA) reduce the physiological and psychological stress levels of first-year female undergraduates. In study I, 27 first-year college women and 9 privately owned registered therapy dogs were recruited. Blood pressure (BP), heart rate (HR), and psychological stress and arousal level were measured and analyzed. In study II, we recruited 61 first-year female students (34 experimental and 28 control) who interacted with 7 registered pet therapy dogs. Salivary cortisol level and psychological stress and arousal level were measured and analyzed for a dog-therapy group and a control group. Animal-assisted activities were associated with a significant decrease in psychological stress and increase in psychological arousal in both studies. There were no significant effects of AAA on diastolic BP, HR, or salivary cortisol level. Our findings indicated that AAA could provide an inexpensive approach to alleviating psychological stress in students and, potentially, other populations of young adults.

We studied the combined effects of energy and protein contents on food selection by the white-footed mouse, Peromyscus leucopus. Our objective was to determine how variation in levels of a food component affected the overall attractiveness of a food to the mice and whether trade-offs are made in selecting dietary protein compared with energy.

Recent studies have shown positive relationships between mass—specific rates of basal metabolism (BMR) and production rates for interspecific comparisons of mammals. This study investigated associations between BMR and production rates by determining whether simultaneous increases in BMR and production occur at the individual level. Growth, reproductive development, and food—processing rates of juvenile Sigmodon hispidus with naturally occurring or experimentally elevated levels of BMR and with ad libitum or restricted food availability were compared. When food was readily available, elevated BMR was associated with higher ingestion rates, faster and more efficient growth, and earlier sexual development. When food was restrived, elevated BMR was associated with severely reduced mass gains. These results suggest that basal metabolism, either directly or indirectly, contributes to mammalian rates of production.

I investigated postnatal growth and sexual maturation, food processing, and reproduction in four subspecies of the hispid cotton rat (Sigmodon hispidus). These traits were compared among subspecies and with previously published data. Subspecific differences in postnatal growth rate, energy digestion and assimilation rates, thyroxin use rate, and mass of neonates were determined in laboratory-reared cotton rats. Sizes of field- and laboratory-conceived litters also were measured. Variability in size of adults and in postnatal growth rate was low among subspecies. The body mass of neonates and mass at vaginal opening and at first estrus differed significantly, however, among most subspecies. Significant differences in sizes of field-conceived litters existed among subspecies, but no significant differences persisted under a single set of laboratory conditions. No significant subspecific differences in energy digestion or assimilation occurred. These results indicate that much of the reported subspecific variation in size of adults, growth, and size of litters that occurs among populations in the field is due to environmental factors.

We studied the combined effects of energy and protein contents on food selection by the white-footed mouse, Peromyscus leucopus. Our objective was to determine how variation in levels of a food component affected the overall attractiveness of a food to the mice and whether trade-offs are made in selecting dietary protein compared with energy. We conducted food-selection tests in the laboratory and field using foods containing different combinations of energy and protein levels. In the laboratory, P. leucopus were offered a choice between a high-energy and a low-energy food with the protein level held constant and between a high-protein and a low-protein food with the energy level held constant. The field study was set up to offer an encounter with all four combinations of energy and protein simultaneously. We also tested for preferred levels of protein using pairwise food-selection tests in the laboratory. In the laboratory and field tests, P. leucopus selected high-energy foods that were low in protein, but avoided all foods with a high protein content. When given pairwise choices among foods containing 5, 15, 25, or 35% protein, P. leucopus consistently preferred the food with 15% protein. Peromyscus leucopus quickly detected differences in protein and energy levels in foods, selecting specific foods according to metabolic profitability and nutrient needs.

I investigated changes in the capacity of the alimentary canal in a moderately small, omnivorous mammal, the raccoon (Procyon lotor). Because of their diverse diet, omnivores may not be dependent upon changes in capacity of the alimentary canal to meet increased energy needs, as are strict herbivores and ruminants. I hypothesized that the capacity of the alimentary canal of lactating and nonreproductive female raccoons would not differ significantly. I also hypothesized that capacity would not differ between summer and winter. Raccoons were captured at Land-Between-the-Lakes, Kentucky. The wet and dry masses, length, and volume of the total gastrointestinal tract and individual organs of the alimentary canal were measured. Results showed that capacity can increase in an omnivorous species in the field. Lactating females had significantly greater wet or dry masses of the total gastrointestinal tract, stomach, and colon than did nonreproductive females. The lengths and volumes of the organs of the alimentary canal also were larger, although not to a significant extent, in lactating females. No significant effect of season occurred on total capacity of the alimentary canal or the capacity of any associated organ. My findings support the contention that change in capacity of the alimentary canal is a fundamental physiological response of mammals to sustained periods of increased demand for energy.