No abstract

Knowledge of patterns of lesion distribution can provide insight into the relative roles played by regional tissue dose and local tissue susceptibility in toxic responses to xenobiotics in the nose and assist assessment of potential human risk. A consistent approach is needed for recording lesion distribution patterns in the complex nasal airways of rats and mice. The present work provides a series of diagrams of the nasal passages of the Fischer-344 rat and B6C3F1 mouse, designed for mapping nasal lesions. The diagrams present each of the major cross-sectional airway profiles, provide adequate space for nasal mucosal lesion recording, and are suitable for duplication in a commercial photocopier. Sagittal diagrams are also provided to permit transfer of lesion location data observed in transverse sections onto the long axis of the nose. The distribution of lesions induced by a selected range of xenobiotics is presented. Approaches to application of the diagrams and interpretation of results obtained are discussed in relation to factors responsible for lesion distribution in the nose and their relevance to interspecies extrapolation. A modified approach to anatomical classification of the ethmoturbinates of the rodent is also presented.

No abstract

A CFD methodology is used to study the performance of several commercial bicycle wheels over a range of speeds and yaw angles. The wheels studied in this work include the Rolf Sestriere, HED H3 TriSpoke, the Zipp 404, 808 and 1080 deep rim wheels and the Zipp Sub9 disc wheel. Wheels are modeled at speeds of 20mph and 30mph, in contact with the ground, using Reynolds-Averaged Navier Stokes (RANS). Drag, vertical and side (or lift) forces are reported for each wheel. Turning moments are also calculated using the resolved side forces to examine aspects of stability and maneuverability. Drag and side forces over the range of yaw angles studied compare favorably to experimental wind tunnel results. The previously reported unique transition from downward to upward acting vertical force on the Zipp 404 wheel for increasing yaw angles is observed for all deep rim wheels and the disc wheel studied here. Wheels were also modeled at a critical yaw angle of 10 degrees using Delayed Detached Eddy Simulation (DDES) to examine the transient aspects of flows around moving bicycle wheels. It is hoped that a more complete comprehension of these results will lead to improvements in performance, safety and control of bicycle racing wheels used by amateur and professional cyclists and triathletes.