Bismuth based nanomaterials have recently attracted attention as heavy element X-ray contrast agents because of the high atomic number and predicted biological compatibility of bismuth. Nanoparticle X-ray contrast agents may enable a number of novel medical imaging applications, including blood pool and site-directed imaging. However these hypothetical applications are hindered by lack of suitable synthetic methods for production of imaging agents. This dissertation describes synthesis of a novel class of bismuth nanoparticles that are aqueously stabilized using poly and monosaccharides. These particles are synthesized using highly biologically compatible reagents and are oxidatively stable in water and in moderately basic buffered solutions. Bismuth nanoparticles stabilized by the polysaccharide dextran have a large hydrodynamic radius and a relatively small bismuth nanocrystal core (4% bismuth by volume.) Glucose-capped particles have a much higher ratio of bismuth by volume (>60%), and experimental CT scans of these particle solutions demonstrate higher X-ray contrast versus a current clinically used radiocontrast agent. Additional syntheses of hydrophobic organoamine-capped bismuth nanoparticles by reduction of an iodobismuth cluster, and development of other X-ray contrast materials, such as a radiopaque surgical sponge marker and ink, using bismuth micoparticles produced by a top-down ball milling method, are also described.

This study examines the concepts of psychodrama and dying, death and bereavement that effectively meet individual needs for working through grief. It is the premise of this thesis that the working through grief to foster acceptance, self-worth and dignity, in the final st.age of life, is facilitated by psychodramatic methods of "acting through" the problems of the situation.

This thesis presents an improved oscillotonometric system for the measurement of human blood pressure. The study included: 1. The design of a hydraulic occlusive cuff, 2. The investigation of the wave forms taken from the blood pressure measurements, and 3. The design of a mechanism for the simulation of human blood pressure pulse. In this study, an experimental system consisting of a rigid shell occlusive cuff, a constant volume displacement pump, a transducer, and a chart recorder was designed and used for data collection.

Documentation exists that mothers can pass the cariogenic bacteria Streptococcus mutans to their infants. The newest technology to identify Streptococcus mutans is a rapid detection saliva test. Two hundred patients above the age of 18 were targeted using random selection in a Louisville, Kentucky dental office. Patients signed an informed consent form and were given a qualifying questionnaire. Patients received 2 bitewing x-rays and a charted DMFT index and were administered the saliva test. While the null hypothesis was rejected using the chi square test, the results were inconclusive due to expected values. However, other chi square results revealed that the test worked or had the potential to work. Furthermore, it was concluded that the test had high specificity. Further research is warranted; however, the saliva test in combination with the DMFT and x-rays are instrumental tools for the dental professional in educating patients and prevention.

The vestibular evoked myogenic potential (VEMP) has been shown to be clinically useful in providing diagnostic information regarding the function of the otolith receptors, inferior vestibular nerve, and vestibulospinal pathways. The VEMP is a biphasic response elicited by loud clicks or tone bursts and recorded from the tonically contracted sternocleidomastoid (SCM) muscle. Because the VEMP is an inhibitory response, it is important to investigate stimulus and parameter characteristics in order to determine the optimal test protocol and maximize clinical usefulness. The aims of this study were 1) to evaluate the effects of 4 different methods of SCM muscle activation and the effect of visual biofeedback on VEMP latency, amplitude, asymmetry ratio, mean rectified EMG level, and difficulty ratings, and 2) to determine the influence of SCM muscle activation pattern and visual biofeedback level on test-retest reliability. Forty-eight healthy volunteers between the ages of 18 and 50 underwent VEMP testing using each of the following muscle activation patterns: supine with the head raised (SE), supine with the head turned away from the test ear (SR), supine with the head raised and turned away from the test ear (SER), and sitting with the head turned away from the test ear (SitR). Testing subjects with the SER method yielded the most robust amplitude response and sternocleidomastoid EMG activity. No statistically significant differences were found in interaural asymmetry ratios among the 4 methods of SCM activation. Subjects rated the SE and SER methods as more difficult than the SE and SitR methods at each of the 3 target levels. Test-retest reliability was high for P1/N1 amplitude and mean rectified EMG levels when subjects were provided visual biofeedback to monitor the level of tonic SCM muscle activity. The study demonstrates the importance of providing patients a means of monitoring and maintaining the amplitude of the rectified EMG at a constant target level during SCM muscle activation. Although no evidence to reject or strongly favor a specific method was found, monaural-ipsilateral recording with the SitR method was found to be advantageous for individuals with weakness or decreased endurance for sustained muscle contraction.

This thesis encompasses a feasibility study of using low-cost materials to manufacture microfluidic chips that can perform the same functions as chips manufactured using traditional methods within an acceptable range of efficiency of chips created with more exotic methods and materials. The major parts of the project are the selection and characterization of the fabrication methods for creating the channels for fluid flow, the methods for sealing the channels to create a usable chip and the electrophoretic separations of carboxylated microspheres of different potentials. In this work we seek to answer the question if laser-etched PMMA microfluidic chips are comparable in functionality to microfluidic chips created with PDMS or glass. In the process of answering this question we will touch on FEA modeling, characterization of the manufacturing process and multiple prototype designs while keeping within the low-cost theme. The purpose of capillary electrophoresis is to separate proteins based on their inherent electric charge. Capillary electrophoresis is a standard chip design used in the microfluidics world to prove a new fabrication method or chip material before branching out to other experiments because it is a fairly simple and robust design. Common problems associated with the manufacturing methods and materials were taken into account such as electroosmotic flow and chip sealing. CZE designs from literature were referenced to create a chip that would separate carboxylated microbeads with reasonable resolution. Wire electrodes were affixed to the chip to induce electric fields for the electrophoresis experiments. The goal of this thesis is to prove the manufacturing methods and attain results within 70% of literature standards.

Surface electromyography (sEMG) and mechanomyography (MMG) are well-studied signals that can reveal information about the physiological behavior of muscles during contraction. The purpose of this study was to quantify, characterize, and analyze the electrical and mechanical muscle responses to submaximal, isometric contractions in the rectus femoris in adults. Previous studies have investigated the use of EMG to monitor muscle fatigue. However, more information appears to be needed about the use of MMG to measure muscle fatigue during submaximal isometric contraction in the rectus femoris. In this study, the utility of MMG as a measure of muscle fatigue or muscle state was investigated. After studying 10 adult subjects (6 females, 4 males) during 2 consecutive fatiguing isometric contractions at 50% MVIC, there was a total sample of 20 contractions. The RMS, frequency, and electromechanical efficiency (EME) were calculated as an average over 2s samples at the beginning, middle and end of the fatiguing contraction for both EMG and MMG. Electrical efficiency and contraction duration were also measured. EMG RMS. MMG RMS, and electrical efficiency showed significant increasing trends during fatiguing exercise (p=0.0001 and p=0.005 respectively). EMG frequency had a significant decreasing trend (p=0.0016). There was also a significant decrease in the contraction duration when fatiguing exercises were repeated in the same session (p=0.0228). EME and MMG frequency did not have significant trends. However, further studies of these parameters during different fatiguing exercises may help expand their utility in monitoring muscle state. Overall, this study suggests that sEMG and MMG may have utility in monitoring muscle fatigue in submaximal, isometric contractions in the rectus femoris. sEMG and MMG may also find future applications in monitoring patients with muscle conditions.

<p>The use of both percutaneous and tunnelled central venous catheters in hospitalized patients has increased markedly over the last decade (Camp-Sorrell, 1990). With this increase, there is a clinical need to have an occlusive central line dressing to maintain a barrier to possible site contamination. This randomized control trial examined the use of the transparent dressing OpSite Wound (Smith and Nephew-Ine.) versus the ransparent dressing LV. 3000 (Smith & Nephew Inc.) in its ability to maintain an occlusive central line dressing. The study took place at Chedoke-McMaster Hospitals McMaster Division from June 1991 to September 1991. Adult medical-surgical patients who had a central line in place for longer than 48 hours were eligible for the study. Twenty five central lines were randomized to either the control group (OpSite Wound) or the experimental group (LV. 3000) An independent assessor saw all study patients daily to document dressing adhesiveness and the number of dressing changes performed. Analysis showed that the LV. 3000 dressing was changed every 5.5 days as opposed to the OpSite Wound dressing that was changed every 2.6 days. This difference was both statistically and clinically significant Analysis also showed that the dressings covering central lines with no intravenous in-line attachment (pigtail) were changed more frequently than the dressings covering central lines with an attached pigtail. This difference was also statistically significant The LV. 3000 dressing therefore, provides an occlusive central line dressing that is changed one-half the number of times that the OpSite Wound dressing is changed, or in other words, the OpSite. Wound dressing is changed twice as often as the I.V. 3000 dressing when used on central lines.</p> / Master of Health Sciences (MSc)

Activation of brain regions that make up the mirror neuron system (MNS) is thought to reflect processing and perceiving behavior, action, and intentionality of other organisms. Sensing and perceiving motor behavior in others is an important component of understanding and participating in social interactions. Children with chromosome 22q11.2 deletion syndrome (22q11.2DS) are diagnosed with serious medical, cognitive, and socio-emotional symptoms. Atypical development and function of the MNS may underpin some aspects of socio-emotional impairment and autism spectrum disorder (ASD)-like symptomology reported. This study of the MNS investigates differences in activation in the operculum, sensorimotor areas, and basal ganglia (BG) in children with 22q11.2DS compared to typically-developing (TD) controls. Twenty-nine children (22q11.2DS: n=15; TD: n=16) between ages 7-16 viewed videos of a human hand manipulating various household objects during a functional magnetic resonance imaging (fMRI) scan. In Analysis 1, children with 22q11.2DS had less extensive brain activation than TD children in the operculum, sensorimotor areas, and BG. In Analysis 2, children with 22q11.2DS had the same results as Analysis 1 with the exception of sensorimotor areas not being highly active in either group. In both analyses, fMRI signal change from baseline to video did not differ significantly between groups. Processing efficiency in children with 22q11.2DS may be lower or more variable when compared to TD peers. This is the first study comparing children with 22q11.2DS to TD peers specifically looking at MNS activation within the operculum region to assess higher cognitive functioning, somatosensory cortex for sensory interpretation, and basal ganglia for gross motor activity. Future studies should compare brain activation between children with ASD and those with 22q11.2DS during an MNS task as the next step to further clarify the origin of ASD symptoms reported in this population.

The development of early diagnostics and prevention strategies for preterm birth is an important global health challenge with the potential to impact over 15 million children annually, by improving health outcomes and reducing economic burden. Advances in microbial sequencing technology have opened the door to 16S rRNA gene survey, whole metagenomics, and whole transcriptomics, providing molecular evidence that the composition of the vaginal microbiome affects pregnancy outcomes in women, particularly those of African descent. A current gap in our molecular level understanding of the vaginal microbiome as it relates to healthy pregnancies is the metaproteome which comprises proteins from both the woman and colonizing microorganisms. Herein, I describe the development of a label-free mass spectrometry-based workflow for preparing and analyzing the vaginal metaproteome as sampled from vaginal swab extracts. The workflow was applied to two longitudinal cohorts of vaginal swab samples collected during the VCU MOMS-PI study. The work presented herein demonstrates for the first time that sufficient vaginal-specific biomaterial can be extracted from swabs for metaproteomics analysis as evidenced by high proteome coverage (>1790 human and >1609 microbial proteins), quantitative readouts for over 37% of identified proteins, and the identification of candidate protein biomarkers that change with gestational age and parturition status.