L. T. Chang

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Introduction: Diffusion MRI modalities, including diffusion tenor imaging (DTI), are commonly used for both research and diagnostic purposes. Diffusion MRI data suffer from a number of artifacts, such as bulk subject motion, eddy current distortion, and susceptibility induced EPI distortion [1-2]. Appropriate pre-processing of diffusion weighted images and(More)
Introduction: The Robust Estimation of Tensors by Outlier Rejection (RESTORE) [1] has been demonstrated to be an effective method for improving tensor estimation on a voxel by voxel basis in the presence of artifactual data points in the diffusion weighted images (DWIs). However, the RESTORE method that combines robust regression and outlier rejection(More)
Introduction: T 1 maps can be computed from spoiled gradient recalled echo (SPGR) images acquired with different repetition times (TRs) and/or flip angles. Recently, the acquisition of high resolution T 1 maps in a clinically feasible timeframe has been demonstrated with Driven Equilibrium Single Pulse Observation of T 1 (DESPOT1) [1]. DESPOT1 derives T 1(More)
Introduction: In typical applications of diffusion tensor MRI (DTI), DT-derived quantities are used to make a diagnostic, therapeutic or scientific determination. In such cases, it is essential to characterize the variability of these tensor-derived quantities. Parametric [1] and empirical methods (e.g., Monte Carlo [2] and Bootstrap [1]) have been proposed(More)
459 Introduction: Corrupted DWI data is known to have a profound effect on diffusion tensor (DTI) derived quantities such as anisotropy (FA), and mean diffusivity (Tr(D)). Corruption can occur for many reasons including bulk subject motion and pulsatile motion from the cardiac cycle
The chin bar of a motorcycle helmet protects the rider from facial and head injuries. To evaluate the protective performance of chin bars against head injuries from facial impacts, an explicit finite element method was used to simulate the Snell Memorial Foundation test and a proposed drop test. The maximum acceleration and Head Injury Criterion (HIC) were(More)
A standard protocol of dosimetric measurements is used by the organizations responsible for verifying that the doses delivered in radiation-therapy institutions are within authorized limits. This study evaluated a self-designed simple auditing phantom for use in verifying the dose of radiation therapy; the phantom design, dose audit system, and clinical(More)
Fruitflies carrying the autosomal recessive mutation transient receptor potential (trp) are blind in bright light because the receptor potential of such a mutant decays almost completely during an intense stimulus. The trp gene has been localized and a set of partially overlapping genomic clones that include the trp gene has been isolated. The stretch of(More)
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