Neptunium, with its rich redox chemistry, has a special position in the chemistry of actinides. With a decades-long history of development of aqueous separation methods for used nuclear fuel (UNF), management of neptunium remains an unresolved issue because of its not clearly defined redox speciation. Neptunium is present in two,...
Reform in science education has often emphasized task-based learning as an instructional method to improve student understanding and retention of concepts, and to promote the development of reasoning and problem-solving. Yet studies assessing student knowledge at the beginning and end of a task-based class show mixed results. Students in task-based...
Collective robotic systems are biologically-inspired and exhibit behaviors found in spatial swarms (e.g., fish), colonies (e.g., ants), or a combination of both (e.g., bees). Collective robotic system popularity continues to increase due to their apparent global intelligence and emergent behaviors. Many applications can benefit from the incorporation of collectives, including...
Greater sage-grouse (Centrocercus urophasianus) were once found in most grassland and sagebrush (Artemisia spp.) habitats east of the Cascades in Oregon. European settlement and conversion of sagebrush steppe into agricultural production led to extirpation of the species in the Columbia Basin by the early part of the 1900s, but sagebrush...
The Valley of Oaxaca, Mexico was home to one of the most intensively-studied archaic states in the New World. Centered at the hilltop city of Monte Albán, the Zapotec State first arose around 500 BC and eventually encompassed much of the present-day state of Oaxaca. But by the Late Classic...
A comprehensive tribal-level classification for the world's subfamilies of Hesperiidae, the skipper butterflies, is proposed for the first time. Phylogenetic relationships between tribes and subfamilies are inferred using DNA sequence data from three gene regions: 943 bp of cytochrome oxidase subunit I (COI) (in the mitochondrial genome), 739 bp of...