Effects of Instructional Model on Student Attitude in an Introductory Biology Laboratory

This study assessed student attitude towards reformed laboratories featuring a factorial design of inquiry (IN) and explicit / reflective (ER) pedagogy to foster nature of science understanding. Students in thirty-one lab sections responded to pre and post semester assessments of their confidence, perception of usefulness, and effectance motivation toward the laboratories. Relative change in attitude (RCA) was not significantly different (p\u3e0.05) among the treatments or their interaction for confidence, usefulness, or effectance motivation. Student self-reports (n = 137) of factors that affected their attitude suggested that grades and TAs played a larger role in determining student attitude than the laboratory treatments. This hints at the complex interactions that impact student attitude, and which should be considered when implementing course reforms

Posterior structural brain volumes differ in maltreated youth with and without chronic posttraumatic stress disorder

Abstract Magnetic resonance imaging studies of maltreated children with posttraumatic stress disorder (PTSD) suggest that maltreatment-related PTSD is associated with adverse brain development. Maltreated youth resilient to chronic PTSD were not previously investigated and may elucidate neuromechanisms of the stress diathesis that leads to resilience to chronic PTSD. In this cross-sectional study, anatomical volumetric and corpus callosum diffusion tensor imaging measures were examined using magnetic resonance imaging in maltreated youth with chronic PTSD ( N = 38), without PTSD ( N = 35), and nonmaltreated participants ( n = 59). Groups were sociodemographically similar. Participants underwent assessments for strict inclusion/exclusion criteria and psychopathology. Maltreated youth with PTSD were psychobiologically different from maltreated youth without PTSD and nonmaltreated controls. Maltreated youth with PTSD had smaller posterior cerebral and cerebellar gray matter volumes than did maltreated youth without PTSD and nonmaltreated participants. Cerebral and cerebellar gray matter volumes inversely correlated with PTSD symptoms. Posterior corpus callosum microstructure in pediatric maltreatment-related PTSD differed compared to maltreated youth without PTSD and controls. The group differences remained significant when controlling for psychopathology, numbers of Axis I disorders, and trauma load. Alterations of these posterior brain structures may result from a shared trauma-related mechanism or an inherent vulnerability that mediates the pathway from chronic PTSD to comorbidity

Early Pliocene fish remains from Arctic Canada support a pre-Pleistocene dispersal of percids (Teleostei: Perciformes)

Percid remains from Pliocene deposits on Ellesmere Island, Arctic Canada, are identified as a species of Sander, similar to the walleye and sauger of North America and the pike-perch of Europe and western Asia. They are named as a new species, Sander teneri. These remains are the most northerly percid elements found to date and suggest the palaeoenvironment was significantly warmer in the Pliocene than it is currently. The fossil remains show the presence in North America of the family Percidae as well as the genus Sander prior to the Pleistocene, indicating a previously proposed Pleistocene immigration from Europe or Asia can be discounted. These fossils contradict an earlier hypothesis that percids, in particular Sander, crossed from Eurasia to North America in the Pleistocene; instead, the fossils show percids were already in the area by the Pliocene