Simulating Anisotropic Thermal Conduction in Supernova Remnants, Implications for the Interstellar Medium

We present a large number of two and a half dimensional simulations of supernova remnants expanding into interstellar media having a range of densities, temperatures and magnetic field strengths. The volume of hot gas produced is strongly dependent on the inclusion of thermal conduction and magnetic fields. The four-volumes and three-areas of hot gas have been catalogued and their dependence on interstellar parameters documented. Simulated line widths of radioactive species ejected by supernovae have also been catalogued

Visualization of longitudinal student data

We use visualization to find patterns in educational data. We represent student scores from high-stakes exams as flow vectors in fluids, define two types of streamlines and trajectories, and show that differences between streamlines and trajectories are due to regression to the mean. This issue is significant because it determines how quickly changes in long-term educational patterns can be deduced from score changes in consecutive years. To illustrate our methods, we examine a policy change in Texas that put increased pressure on public school students to pass several exams, and gave them resources to accomplish it. The response to this policy is evident from the changes in trajectories, although previous evaluation had concluded the program was ineffective. We pose the question of whether increased expenditure on education should be expected to correspond to improved student scores, or whether it should correspond to an increased rate of improvement in student scores

The neuropathogenesis of feline immunodeficiency virus infection: Barriers to overcome

Feline immunodeficiency virus (FIV), like human immunodeficiency virus (HIV)-1, is a neurotropic lentivirus, and both natural and experimental infections are associated with neuropathology. FIV enters the brain early following experimental infection, most likely via the blood-brain and blood-cerebrospinal fluid barriers. The exact mechanism of entry, and the factors that influence this entry, are not fully understood. As FIV is a recognised model of HIV-1 infection, understanding such mechanisms is important, particularly as HIV enters the brain early in infection. Furthermore, the development of strategies to combat this central nervous system (CNS) infection requires an understanding of the interactions between the virus and the CNS. In this review the results of both in vitro and in vivo FIV studies are assessed in an attempt to elucidate the mechanisms of viral entry into the brain