Casework with mentally ill clients at a family service agency

Thesis (M.S.)--Boston Universit

Bibliography of Doctor Chul Park

This document contains a comprehensive bibliography of the published works, and a short biography, of Dr. Chul Park. The contents of this bibliography were compiled primarily from the NASA RECON data base. The RECON citations have been modified to appear in a uniform format with all other listed citations . These other citations were located by computer searches in the INSPEC, NTIS, COMPENDEX, and Chemical Abstracts data bases, as well as through the cooperation of Dr. Chul Park, and his associates in the Reacting Flow Environments Branch at NASA Ames Research Center. All citations are presented in an approximate reverse chronological order from the present date. This work was created to honor the occasion of Dr. Chul Park's retirement on December 14, 1994, after 27 years of distinguished government service at the NASA Ames Research Center

Fast Bound Pool Fraction Mapping Using Stimulated Echoes

Magnetization transfer imaging advanced to an indispensible tool for investigating white matter changes. Quantitative magnetization transfer imaging methods allow the determination of the bound pool fraction (BPF), which is thought to be directly linked to myelin integrity. Long acquisition times and high specific absorption rates are still inhibiting broad in vivo utilization of currently available BPF mapping techniques. Herewith, a stimulated echoes amplitude modulation-based, single-shot echo planar imaging technique for BPF and T1 quantification is presented at 3T. It allows whole brain mapping in 10–15 min and is low in specific absorption rates. The method was validated with different concentrations of bovine serum albumin (BSA) phantoms. Intra- and inter-subject variability was assessed in vivo. Phantom measurements verified linearity between bovine serum albumin concentrations and measured BPF, which was independent of T1 variations. T1 values in the phantoms correlated well with values provided by standard T1 mapping methods. Intrasubject variability was minimal and mean regional BPFs of 10 volunteers (e.g., left frontal white matter = 0.135 ± 0.003, right frontal white matter = 0.129 ± 0.006) were in line with previously published data. Assessment of interhemispheric BPF differences revealed significantly higher BPF for the left brain hemisphere. To sum up, these results suggest the proposed method useful for cross-sectional and longitudinal studies of white matter changes in the human brain. Magn Reson Med, 2011. © 2011 Wiley-Liss, Inc

P130Cas Src-Binding and Substrate Domains Have Distinct Roles in Sustaining Focal Adhesion Disassembly and Promoting Cell Migration

The docking protein p130Cas is a prominent Src substrate found in focal adhesions (FAs) and is implicated in regulating critical aspects of cell motility including FA disassembly and protrusion of the leading edge plasma membrane. To better understand how p130Cas acts to promote these events we examined requirements for established p130Cas signaling motifs including the SH3-binding site of the Src binding domain (SBD) and the tyrosine phosphorylation sites within the substrate domain (SD). Expression of wild type p130Cas in Cas −/− mouse embryo fibroblasts resulted in enhanced cell migration associated with increased leading-edge actin flux, increased rates of FA assembly/disassembly, and uninterrupted FA turnover. Variants lacking either the SD phosphorylation sites or the SBD SH3-binding motif were able to partially restore the migration response, while only a variant lacking both signaling functions was fully defective. Notably, the migration defects associated with p130Cas signaling-deficient variants correlated with longer FA lifetimes resulting from aborted FA disassembly attempts. However the SD mutational variant was fully defective in increasing actin assembly at the protruding leading edge and FA assembly/disassembly rates, indicating that SD phosphorylation is the sole p130Cas signaling function in regulating these processes. Our results provide the first quantitative evidence supporting roles for p130Cas SD tyrosine phosphorylation in promoting both leading edge actin flux and FA turnover during cell migration, while further revealing that the p130Cas SBD has a function in cell migration and sustained FA disassembly that is distinct from its known role of promoting SD tyrosine phosphorylation

Experimental studies of g-ratio MRI in ex vivo mouse brain

This study aimed to experimentally evaluate a previously proposed MRI method for mapping axonal g-ratio (ratio of axon diameters, measured to the inner and outer boundary of myelin). MRI and electron microscopy were used to study excised and fixed brains of control mice and three mouse models of abnormal white matter. The results showed that g-ratio measured with MRI correlated with histological measures of myelinated axon g-ratio, but with a bias that is likely due to the presence of non-myelinated axons. The results also pointed to cases where the MRI g-ratio model simplifies to be primarily a function of total myelin content

Relayed nuclear Overhauser enhancement sensitivity to membrane Cho phospholipids

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155956/1/mrm28258_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155956/2/mrm28258.pd

Non-invasive Predictors of Human Cortical Bone Mechanical Properties: T2-Discriminated 1H NMR Compared with High Resolution X-ray

Recent advancements in magnetic resonance imaging (MRI) have enabled clinical imaging of human cortical bone, providing a potentially powerful new means for assessing bone health with molecular-scale sensitivities unavailable to conventional X-ray-based diagnostics. To this end, 1H nuclear magnetic resonance (NMR) and high-resolution X-ray signals from human cortical bone samples were correlated with mechanical properties of bone. Results showed that 1H NMR signals were better predictors of yield stress, peak stress, and pre-yield toughness than were the X-ray derived signals. These 1H NMR signals can, in principle, be extracted from clinical MRI, thus offering the potential for improved clinical assessment of fracture risk

The current state-of-the-art of spinal cord imaging: methods.

A first-ever spinal cord imaging meeting was sponsored by the International Spinal Research Trust and the Wings for Life Foundation with the aim of identifying the current state-of-the-art of spinal cord imaging, the current greatest challenges, and greatest needs for future development. This meeting was attended by a small group of invited experts spanning all aspects of spinal cord imaging from basic research to clinical practice. The greatest current challenges for spinal cord imaging were identified as arising from the imaging environment itself; difficult imaging environment created by the bone surrounding the spinal canal, physiological motion of the cord and adjacent tissues, and small cross-sectional dimensions of the spinal cord, exacerbated by metallic implants often present in injured patients. Challenges were also identified as a result of a lack of "critical mass" of researchers taking on the development of spinal cord imaging, affecting both the rate of progress in the field, and the demand for equipment and software to manufacturers to produce the necessary tools. Here we define the current state-of-the-art of spinal cord imaging, discuss the underlying theory and challenges, and present the evidence for the current and potential power of these methods. In two review papers (part I and part II), we propose that the challenges can be overcome with advances in methods, improving availability and effectiveness of methods, and linking existing researchers to create the necessary scientific and clinical network to advance the rate of progress and impact of the research