Nanomaterials are widely used as pseudostationary and stationary phases in electrically driven capillary separations. The advantages of nanomaterial incorporation into capillary electrophoresis (CE) are numerous and include tunable sizes, multiple core compositions, flexible injection/introduction methods in separation techniques, and diverse surface chemistry options. Nanomaterials, however, exhibit inherently large surface energies which induce aggregation and as a result, yield unpredictable function in separations. Because nanomaterials can modify buffer conductivity, viscosity, and pH; separation optimization and nanoparticle stability must be considered. Successful incorporation of nanomaterials into reproducible separations requires (1) strict nanomaterial synthetic control and (2) detailed characterization of the nanoparticle in terms of both core material and surface chemistry. For this reason, this dissertation investigates how the surface chemistry on and morphology of gold nanoparticles impact capillary electrophoresis separations. The gold nanoparticle core composition, shape, size, self assembled monolayer (SAM) formation kinetics, and SAM ligand packing density are all evaluated for thioctic acid, 6-mercaptohexanoic acid, or 11-mercaptoundecanoic acid monolayers. Transmission electron microscopy (TEM), 1H NMR, extinction spectroscopy, zeta potential, X-ray photoelectron spectroscopy (XPS), and flocculation studies are used to assess the morphology, surface chemistry, optical properties, surface charge, SAM packing density, and effective stability of carboxylated nanoparticles, respectively. Using these well-characterized nanostructures, applications of gold nanoparticle pseudostationary phases in capillary electrophoresis is studied. Gold nanoparticles functionalized with mixed SAMs composed of thioctic acid and either 6-mercaptohexanoic acid or 6-aminohexanethiol impact the mobility of possible Parkinson's disease biomarkers in a concentration and surface chemistry dependent manner. From these data, a critical nanoparticle concentrations is developed to characterized nanoparticle stability during capillary electrophoresis separations. To understand the function of these and other carboxylated gold nanoparticles, extended DLVO theory is used to model interparticle interactions during electrically driven flow. 11-Mercaptoundecanoic acid functionalized gold nanoparticles suppress current, while 6-mercaptohexanoic acid and thioctic acid functionalized nanoparticles enhance separation current. Nanoparticle aggregation leads to electron tunneling effects between nanoparticles thereby increasing currents in poorly ordered SAMs while highly packed monolayers induce reversible flocculation characteristics and reduce current. In all cases, these effects are dependent on nanoparticle concentrations. Finally, surface chemistry optimized carboxylic acid functionalized gold nanoparticles effect the separation of hypothesized Parkinson's disease biomarkers. SAM composition and surface coverage impact separation efficiency, resolution, and selectivity. These effects are most systematic with well ordered SAMs. To understand the mechanism functionalized gold nanoparticles exhibit during a separation, their zeta potential with and without dopamine are evaluated. Nanoparticle to dopamine mole ratios (i.e. large dopamine concentrations), neutralize the three functionalized gold nanoparticles according to a dose response curve. The positively charged dopamine molecules saturate the negatively charged nanoparticle surfaces and aggregate thereby providing a plausible explanation to the biomarker concentration trends observed in capillary electrophoresis. These and future studies provide a rigorous experimental and theroretical evalauation of how nanoparticle structure impacts their function as pseudostationary phases in separations and other applications.

Doctor of Clinical Neuropsychology/Master of Science / Introduction: Parkinson’s disease (PD) is known to cause detrimental effects to motor function and cognition. The motor effects of the disease in turn impact emotion expression in patients with PD. There is conflicting evidence in research, however, as to whether PD also affects emotion comprehension, and if so, what emotions in particular are affected and across what modalities. This study aimed to investigate the effects of PD on a broad range of skills involved in basic and complex emotion comprehension. Whether these effects extend into other areas associated with emotion processing, such as social cognition and autobiographical memory, was also explored. Methods: Sixteen patients with PD participated in the study along with sixteen control subjects who were matched for age, gender, education level and estimated premorbid intelligence. The PD participants, on average, were in the moderate phase of the disease and taking PD medication, including dopamine. Participants were tested on a range of recognition measures including prototypical and morphed facial expressions with reduced intensity (40 and 80%), emotion prosody, written emotion vignettes, emotional imagery, pictures of emotion, social cognition, and a cued autobiographical memory task. A mood inventory was given, and disease severity and duration were noted. Results: The PD group did not show pervasive deficits in emotion recognition overall. Deficits were demonstrated in prosody recognition, specifically with fearful tones, and in an incongruent prosody task, specifically with angry and neutral tones. The PD group was not able to recognise facial expressions of disgust (mixed intensities) as well as controls, with the result showing a trend toward significance. PD participants were also significantly worse in Theory of Mind (TOM) reasoning but not at another social cognition measure involving recognising social emotions through expressions from the eyes only. There were no differences between the groups across all other tests. Discussion: PD is thought to cause subtle deficits in emotion comprehension which are only elucidated through complex tasks. The effects of PD on complex processing also impact TOM performance, which relies on skills involved in complex emotion recognition. Effects of mood and disease factors on performance were circumscribed. Evidence suggested that the basal ganglia and fronto-striatal connections play a role in emotion comprehension.

Thesis (Ph. D.)--University of Massachusetts Amherst, 2009. / Open access. Includes bibliographical references (p. 100-112). Print copy also available.

No description available.

The primary aim of this pilot study was to evaluate the effects of a novel dysphagia rehabilitation approach: skill training on swallowing in individuals who have dysphagia secondary to Parkinson’s disease. The secondary objective was to assess skill retention following treatment termination. This within-subject study involved 10 patients with Parkinson’s disease who met the inclusionary criteria. All participants underwent two baseline data collection sessions, conducted two weeks apart. Data collected included the water swallow test, Test of Mastication and Swallowing Solids (TOMASS), ultrasound measurement of hyoid movement and cross-sectional area of submental muscles, surface electromyography (sEMG) of submental muscles, and swallowing-related quality of life questionnaire (SWAL-QOL). Patients then underwent 10 sessions over two weeks of skill training therapy using custom-designed sEMG software. The focus of the treatment was producing swallowing tasks with defined and adjustable temporal and amplitude precision. The skill training treatment phase was followed by an immediate post-intervention assessment session and two weeks later by a retention assessment session. All outcome measures were administered at each data collection point. The study consisted of a total of 14 laboratory sessions, conducted over a six-week period per subject. Results revealed significant improvements in swallowing efficiency for liquids, reduced durational parameters on sEMG, such as pre-motor time (PMT), pre-swallow time (PST), and duration of submental muscle contraction. There was a functional carry-over effect seen from dry swallows, which were the focus of training, to water swallows, which were not directly trained. Additionally, improvements in swallowing-related quality of life were demonstrated. In conclusion, the skill training approach evaluated in this research is able to produce functional, biomechanical, and swallowing-related quality of life improvements in patients with Parkinson’s disease. This indicates the potential effectiveness of this novel approach for dysphagia rehabilitation in this population. However, replication with a larger number of patients with Parkinson’s disease is needed before findings can be generalised to the larger population

No description available.

Many studies have found evidence of abnormal eye movement control in Parkinson's disease. Deficits in the inhibition of unintended saccades and slowed initiation of intentional saccades have been reported in some, but not all, investigations. Also over recent years the presence of cognitive impairment in a proportion of patients with Parkinson's disease has been highlighted. Efficient use of working memory resources is thought to be involved in the performance of tasks in both domains. With a comprehensive selection of saccadic and neuropsychological tasks, the current study investigated whether aspects of abnormal oculomotor control are associated with impairment of cognitive functions. Nineteen Parkinson's disease patients and eighteen healthy age matched control subjects performed six eye movement tasks and completed a neuropsychological test battery assessing five different aspects of cognitive functioning. Deficits were found in both the oculomotor and the cognitive domain in the group of patients. As a group, the patients made more reflexive errors in antisaccade tasks, more inhibition errors in a delayed response task, and were slower to initiate intentional saccades. The three measures of abnormal oculomotor control were not consistently associated with cognitive impairments or with each other. Longer latencies of correct antisaccades and increased number of errors in a delayed response task were associated with lower scores in different cognitive tests. Reflexive errors in the antisaccade task were not associated with cognitive deficits, but with the tendency to produce very fast visually triggered responses. The results suggest that, at least in Parkinson's disease, different neural mechanisms may be involved in specific aspects of abnormal oculomotor control.

Doctor of Clinical Neuropsychology/Master of Science / Introduction: Parkinson’s disease (PD) is known to cause detrimental effects to motor function and cognition. The motor effects of the disease in turn impact emotion expression in patients with PD. There is conflicting evidence in research, however, as to whether PD also affects emotion comprehension, and if so, what emotions in particular are affected and across what modalities. This study aimed to investigate the effects of PD on a broad range of skills involved in basic and complex emotion comprehension. Whether these effects extend into other areas associated with emotion processing, such as social cognition and autobiographical memory, was also explored. Methods: Sixteen patients with PD participated in the study along with sixteen control subjects who were matched for age, gender, education level and estimated premorbid intelligence. The PD participants, on average, were in the moderate phase of the disease and taking PD medication, including dopamine. Participants were tested on a range of recognition measures including prototypical and morphed facial expressions with reduced intensity (40 and 80%), emotion prosody, written emotion vignettes, emotional imagery, pictures of emotion, social cognition, and a cued autobiographical memory task. A mood inventory was given, and disease severity and duration were noted. Results: The PD group did not show pervasive deficits in emotion recognition overall. Deficits were demonstrated in prosody recognition, specifically with fearful tones, and in an incongruent prosody task, specifically with angry and neutral tones. The PD group was not able to recognise facial expressions of disgust (mixed intensities) as well as controls, with the result showing a trend toward significance. PD participants were also significantly worse in Theory of Mind (TOM) reasoning but not at another social cognition measure involving recognising social emotions through expressions from the eyes only. There were no differences between the groups across all other tests. Discussion: PD is thought to cause subtle deficits in emotion comprehension which are only elucidated through complex tasks. The effects of PD on complex processing also impact TOM performance, which relies on skills involved in complex emotion recognition. Effects of mood and disease factors on performance were circumscribed. Evidence suggested that the basal ganglia and fronto-striatal connections play a role in emotion comprehension.

Thesis (Ph. D.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains vii, 68 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 42-56).

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 66-76). Also available on the Internet.