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While plant secondary metabolites have played integral roles in human health, food, and industry for thousands of years, still relatively little is known about the genetic mechanisms that generate their incredible diversity, nor their long-term effects on plant species colonization and persistence in harsh habitats. Yaupon holly (Ilex vomitoria) is a plant native to the coasts of the southeastern US whose leaves are used to brew a caffeine-containing infusion similar to tea. Its unique phytochemistry, wide adaptability, and observed variation in secondary metabolite profiles make it an excellent system to study how the production of plant secondary metabolites is shaped by adaptative evolution, but the underlying evolutionary history of this plant remains unknown, and its secondary chemistry has yet to be fully characterized. To address these gaps, we are constructing a living diversity panel comprised of ~300 live, wild yaupon holly plants self-collected from across the Southeast, each paired with genotyping-by-sequencing data. Using this genotype data, we aim to answer foundational questions about the evolutionary history of yaupon holly and probe the genome for evidence of recent adaptation in secondary metabolic processes. We also present preliminary data on the secondary metabolic composition of yaupon holly generated using LC-MS, both in green leaves and post-tea processing. Upon completion of these objectives, we hope to shed light on the forces that shape plant secondary metabolism at the level of communities and populations, as well as lay a foundation for future research in this organism. [ABSTRACT FROM AUTHOR]

The article presents a study which compared the muscle work during incline and decline walking in lean and obese adults. In the study, three-dimensional (3D) motion capture and force plate systems were utilized to determine the lower limb joint powers during incline and decline walking in a sloped path. The study proved the global hypothesis that skeletal muscles produce more mechanical energy in gait tasks that increase the center of mass than gait tasks that lower the center of mass.