Shannon MacKenzie, Ph.D. Candidate, Physics
TITLE: “Liquid Detectives: Titan's Evaporites”
ABSTRACT: Titan, Saturn's largest moon, is incredibly Earth-like. It has a thick atmosphere, rain, lakes and seas... but Titan is a chemically different world! Instead of water, the rain and surface liquid is all methane and ethane! Unlike Earth where we have oceans of water taking up much of the planet's surface, Titan's liquid is almost exclusively found at the North Pole. My research is helping shed light on this mystery by characterizing the surface deposits left behind when liquid evaporates, evaporites (think the mineral ring in your bathtub). By identifying where evaporites are and what they are made of, we can look into Titan's past and see where liquid has been.
Charlotte Milling, Ph.D. Candidate, Natural Resources
TITLE: “Outmaneuvering climate change: behavior buffers a small, arid land mammal against thermal extremes”
ABSTRACT: Understanding behavioral responses of animals to the thermal environment is of increasing importance under changing climate regimes. Seeking thermally suitable rest sites, or refugia, and flexibility in timing of activity to avoid thermal extremes are important behavioral strategies that might buffer some animals from the effects of global climate change. These strategies are examples of what is referred to as behavioral thermoregulation. Our objectives were to quantify behavioral thermoregulation strategies in a small, arid land mammal to test the hypotheses that individuals would exploit thermal refugia and alter activity patterns seasonally and daily as a function of the thermal environment. We radio-collared 52 pygmy rabbits (Brachylagus idahoensis) to identify rest sites used during summer and winter, and we applied a modeling approach to estimate a resource selection function (RSF), which identifies factors that are important in rest site selection. We also fitted 24 rabbits with motion detectors to quantify activity seasonally, during daily periods (dawn, day, dusk, and night), and in relation to daily extreme temperatures. During summer, rabbits selected rest sites that were cooler than unused nearby locations and strongly avoided high levels of solar radiation. In winter, however, the thermal environment did not significantly influence rest site selection. In both seasons, activity was characterized by high peaks during dawn and dusk, but contrary to our expectations, was not related to daily high or low temperatures. Sex and moon phase significantly influenced activity patterns, suggesting high levels of flexibility in timing of activity. These behaviors may provide thermoregulatory options that potentially buffer pygmy rabbits and other small mammals against a changing climate. Management that promotes spatial diversity within a habitat to provide thermal refugia may help to support long-term conservation of vulnerable mammals.
3MT® People’s Choice Award
Yvonne Nyavor, Ph.D. Candidate, Neuroscience
TITLE: “Manniflavanone: The 'Magic Pill' we've been searching for?”
ABSTRACT: 90-95% of 29.1 million diabetic Americans have Type 2 Diabetes (T2D), an illness commonly associated with central obesity and consumption of high amounts of fat in a western diet. T2D is a debilitating disease due to numerous complications including enteric neuropathy, which is the underlying cause of gastrointestinal dysfunction. Oxidative stress and low-grade inflammation are among key factors underlying the development of diabetic neuropathy. To date, effective therapies for obesity, T2D and resultant neuropathy are not available. Therefore, the aim of this study was to test the hypothesis that manniflavanone (MNF), a powerful antioxidative and anti-inflammatory is effective at mitigating high fat diet (HFD)-induced obesity and T2D in a mouse model. 6-week-old C57Bl/6J male mice were fed standard chow diet (SCD) or 72%kcal HFD for 4 weeks. Mice were then treated with MNF, alphalipoic acid (ALA) or left untreated for 4 weeks. ALA was used as a positive control for it is an anti-oxidative molecule used to treating neuropathy in T2D patients in some European countries. Drugs were administered ad libitum via drinking water. We then assessed markers for T2D and obesity, and measured neuromuscular and synaptic neurotransmission in the intestine. Mice were significantly heavier, glucose intolerant, insulin resistant, and had increased adiposity after 4 weeks on HFD. Manniflavanone and ALA treatment reduced the amount of weight gained on HFD, and lowered insulin resistance. In addition, both MNF and ALA treated mice had lower circulating levels of resistin and leptin in comparison to untreated mice. HFD reduced neuromuscular and synaptic neurotransmission. These effects were reversed by ALA and MNF treatment. These results suggest that manniflavanone is an effective treatment for HFD induced obesity, diabetes, and diabetic enteric neuropathy.