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Auditory perception and cortical plasticity after long-term blindness
No full textThesis (Ph.D.)--University of Washington, 2016-03The study of blindness provides a context for examining neural plasticity in the adult and developing brain, and for asking basic questions about the principles that guide neural computation in sensory cortex. By noting how a system operates when its inputs are altered, we gain insight into the rules that govern its function. The experiments described in this dissertation combine functional magnetic resonance imaging (fMRI) with behavioral methods and computational modeling to examine three issues: (1) Does longstanding blindness affect the cortical representation of auditory frequency? (2) Can we relate cortical representations of auditory frequency to behavioral discrimination, and/or to higher-order phenomena like auditory motion processing? (3) How do visual and auditory responses in adult sight-recovery subjects compare to responses observed in individuals without a history of blindness, and in those with sustained blindness
Self-Reported Fall and Associate Risk Factors Among Korean American Adults In Washington State
No full textThesis (Master's)--University of Washington, 2016-06Falls are leading cause of injuries and mortality among older adults. With increasing life expectancies and continual rise in health care expense, prevalence and cost of falls will increase dramatically. Previous studies have identified multiple risk factors that contribute to falls and fall related injuries however, not all older adults equally share these risk factors. There is a lack of research on Asian American fallers and to date, no study has examined falls among Korean Americans. To fill this gap in research, this thesis aims to examine the prevalence of self-reported falls and to identify associated risk factors of falls among Korean Americans adults in Washington State. Using an existing dataset from a previous study, self-reported falls and medical care due to falls were analyzed. The data comes from a 2013 population-based, cross-sectional survey and included the responses of 261 Korean American adults, aged 50 and older, residing in Seattle metropolitan area. The outcome variable is participants’ fall status within the past 12 months. Predictor variables are socio-demographic, health factors, acculturation, financial concerns for medical care costs, and medical tourism. Relationships between variables were examined using chi-square, bivariate, and multivariate logistic regression. In multivariate modeling, including marital status, household income, and current health status were significantly associated with fall. Unmarried participants were 2.65 (95% CI: 1.09-6.41) higher odds of falling compared to married. Participants with household income of 39,999 were 4.62 (95% CI: 1.38-15.42) higher odds compared to income less than 40,000 or more. Participants who reported their health as fair and poor were 3.13 (98% CI: 1.36-7.19) higher odds compared to participants with good and excellent health. Characteristics of KAs who sought care for their fall were female (46.4% vs. 30.0%), older (75±10.9 vs. 67±11.78). The findings indicates that low income and fair or poor self-reported health were one of the key risk factors for fall among Korean Americans and highlight the needs for race specific fall strategies to reduce the burden of falls in all race group
SITE 1121 - FIELD NOTES Revealing Deep Form as a Basis for Urban Landscape Design
No full textThesis (Master's)--University of Washington, 2016-06What happens when you open the gate on an abandoned urban site and invite people simply to explore what is there? Site 1121- Field Notes establishes a unique landscape design method for immersive site investigation. The project focuses this method onto a vacant urban site, engaging the public and designers in an unfolding dialog that broadens the definition of Landscape Architecture to include temporary site installations. This experimental site installation expands the normal stage of site analysis to include on-site exploration as a design approach. It incorporates craft, proprioceptive experience, and group dialog into design research, balancing art and science in a manner germane to landscape architecture. The more we understand the complex interplay between natural, built, and human conditions, the more landscape emerges as a profoundly meaningful process in which people bodily and purposefully interact with a site. Drawing from archaeological field methods, where the focus is on a narrative hidden in the very materials of a site, Site 1121 directs participants’ attention to the revealed urban terrain as a source of wonder
Utilizing Assessment Resources to Support Classroom Instruction in Mathematics
No full textDoctor of Educational Leadership (EdD)Mathematics teachers in the state of Washington have the responsibility of helping students develop the knowledge and skills included in the Mathematics K-12 Learning Standards (also known as the Common Core State Standards for Mathematics) and measured by the Smarter Balanced summative assessments in mathematics. A great need existed for teachers to have additional support to help students learn the standards and be prepared to demonstrate their knowledge on the Smarter Balanced assessments as well as more working knowledge of how to utilize the supports provided within the system of Smarter Balanced. Mathematics educators in the state of Washington were surveyed at the end of the 2015 school year for the purpose of gathering information on awareness and use of available Smarter Balanced assessment resources and to recommend additional resources, support, and best ways to communicate to the field about the resources. As a result of the teacher feedback, the mathematics assessment department at the Washington State Office of Superintendent of Public Instruction (OSPI) developed resource and support documents to supplement those available from Smarter Balanced. The website location where the documents were uploaded was redesigned to highlight the resources, for easier navigation, and better access by grade level
Youth Empowerment for Environmental Justice
No full textDoctor of Educational Leadership (EdD)Woodsmoke pollution is an environmental justice issue for youth living in certain Pacific Northwest cities. Little is understood about how youth may be empowered to address woodsmoke issues in their communities. In this study, I examined youth empowerment in a citizen science study on woodsmoke, using Photovoice methodology. Ten diverse youth collected and analyzed indoor air samples and photos, then presented their findings to the community and policy makers. Entrance and exit surveys revealed an increased sense of empowerment to take action on woodsmoke pollution. Youth also expressed increased optimism and a resolve to become scientists and to combat environmental injustices
Layer 2.5 Network Coding to Improve 802.11 Network Efficiency
No full textThesis (Master's)--University of Washington, 2016-06The principles of Network Coding have been developed conceptually for over a decade (starting with key results c. 2003 on network coding for butterfly networks). Despite several subsequent extensions to wireless networks, there exists remarkably few implementations of Wireless Network Coding (WNC) techniques within existing wireless networking technology. In this thesis, we present a novel Layer 2.5 implementation for WNC system that can be retrofitted to existing 802.11 nodes (APs and client) with some minimal changes (i.e. is backward compatible with legacy nodes that do not implement WNC) to improve network throughput, when there exist significant intra-network symmetric traffic flows. We implement L2.5 WNC on an 802.11 software defined radio test-bed to experimentally collect data and demonstrate feasibility. We experiment using a simple network with 2 clients and 1 access point. The clients saturate the network by sending messages to each other through the access point whenever possible. Our experimental results show that on average, adding L2.5 network coding to an 802.11 network increases the network efficiency by 11.7% and throughput by 13.6%
Investigating the Effect of Histone H4 Sumoylation on Chromatin Structure and Function
No full textThesis (Ph.D.)--University of Washington, 2016-06The packaging of DNA within the nucleus of a eukaryotic organism is facilitated by the formation of a nucleoprotein complex known as chromatin. There are various DNA binding proteins that play an important part in this process, but the four core histone proteins namely, H2A, H2B, H3 and H4 are essential for forming the scaffolding for DNA packaging. The basic repeating unit of chromatin is called a nucleosome and is formed when 147 bp of DNA wrap around an octamer of histone proteins. The N-terminal regions of all four histones, known as histone tails, protrude out from the nucleosome and are accessible to various chromatin binding complexes. These complexes are capable of modifying histone tails with post-translational modifications (PTMs) that range from small chemical groups such as methyl, acetyl and phosphoryl to small proteins including ubiquitin and different isoforms of the small ubiquitin-like modifier (SUMO). Dysregulation of histone PTMs has been observed in many disease states, which makes the study of these PTMs essential for understanding a variety of pathologies. We focused on the poorly understood modification of histones by SUMO protein, because several components of the sumoylation and desumoylation pathway have been implicated in cancers of the breast, colon, ovaries and prostate. H4 sumoylation has been indirectly linked to transcriptional repression, but the precise effect of histone sumoylation on chromatin structure and function is still unknown. We utilized our expertise in chemical biology to synthesize homogeneous sumoylated histone H4 and incorporated it into chromatin arrays. Through analytical ultracentrifugation experiments we discovered that sumoylation inhibits chromatin compaction and aggregation. To our knowledge, this is the first reported repressive mark that favors a euchromatic state of chromatin. We further corroborated these results with single-molecule FRET studies and uncovered an intrinsic effect of SUMO in preventing inter- and intra-array interactions. Mechanistic studies into the effect of sumoylation revealed that SUMO’s steric bulk plays an important role in preventing the compaction of chromatin arrays. This unexpected result, namely, that a repressive mark favors the euchromatic state led us to further examine the biochemical pathways by which sumoylation might mediate transcriptional repression. We explored the effect of sumoylation of H4 on the activity of the LSD1/CoREST/HDAC complex, which has been known to mediate gene repression through its deacetylation and demethylation activities. We tested the hypothesis that SUMO can mediate repression by localizing the LSD1/CoREST complex by binding to the SUMO interaction motif found in CoREST. We focused on the demethylation of methylated Lys4 of H3 (H3 K4me2), which is a mark associated with transcriptionally active promoter regions. To this end, we performed the first reported synthesis of the native full-length H3 K4me2, which was incorporated into nucleosomes along with sumoylated H4. On comparing the rate of demethylation of H3 K4me2 by the LSD1/CoREST complex, in sumoylated and non-sumoylated nucleosomes, we discovered that sumoylation can facilitate the removal of this activating mark. This novel cross talk between sumoylation and methylation presents one possible pathway by which histone sumoylation can mediate transcriptional repression
Comparison of Objectively and Subjectively Measured Sedentary Behavior in Men with Prostate Cancer and a History of Androgen-Deprivation Therapy Use
No full textThesis (Master's)--University of Washington, 2016-08Men with prostate cancer commonly receive Androgen Deprivation Therapy (ADT) treatment at some point during treatment. Though efficacious, ADT has significant side effects, including increased risk of cardiovascular disease (CVD) and diabetes. Emerging evidence indicates that reducing sedentary behavior (SB) may reduce the risk of diabetes and CVD. Given the co-morbidities, increased age, and side-effects of treatment among men with prostate cancer, reducing SB may offer a feasible means of reducing side effects associated with ADT. Eighteen men with prostate cancer and a history of ADT use completed a single-item sedentary time survey question. Participants were then fitted with accelerometers and objective SB was measured over seven days. Objective and self-reported measures of SB were then compared using Pearson correlation and Bland Altman Plots. Qualitative perceptions of SB were collected through semi-structured exit interviews at follow-up. On average participants underreported SB (5.9 hours/day, ±3.1) compared to objectively measured SB (9.6 hours/day, 2.5). Pearson correlation between objective and self-reported SB was .22 (p = 0.4). Bland-Altman plots indicated that participants underreported SB by 3.5 hours compared to objective measures. When discussing SB, participants commonly cited barriers to decreasing SB, facilitators for increasing SB, and perceptions of current SB. This pilot data suggest that men with prostate cancer and a history of ADT use have high levels of SB, but are largely unaware of their actual SB. While they are overwhelming interested in reducing their sedentary time, health reasons, lack of awareness, and enjoyment of sedentary activities present significant barriers to reducing sedentarism
Mechanisms and biomarkers of cadmium induced neurobehavioral impairment in the olfactory system of coho salmon (Oncorhynchus kisutch)
No full textThesis (Ph.D.)--University of Washington, 2016-03Pacific salmon populations on the west coast of the U.S. are increasingly threatened by anthropogenic activities. One potential factor driving the population declines is disruption of olfactory function via waterborne pollutants. The salmon olfactory system is highly susceptible to disruption by waterborne pollutants such as metals. A majority of the current research has focused on the olfactory toxicity of waterborne copper, while other metals such as cadmium (Cd) have gone relatively understudied. This is a large concern as Cd is a common pollutant in many urban and agricultural waterways, some of which can be important salmon migratory routes. For my doctoral research, I focused on understanding the mechanisms underlying Cd mediated olfactory dysfunction using juvenile coho salmon parr (Oncorhynchus kisutch). The research goals for aim 1 of my project were to analyze olfactory-mediated alarm responses, epithelial injury and recovery, and a suite of olfactory molecular biomarkers encoding genes critical in maintaining olfactory function in juvenile coho salmon receiving acute exposures to Cd. The mRNA molecular biomarkers analyzed included four G-protein coupled receptors (GPCRs) representing the two major classes of odorant receptors, as well as markers of neurite outgrowth and metal/antioxidant responses to metals. Coho received acute (8-168hr) exposures to 3.7 µg/L and 347 µg/L Cd, and a subset of fish was analyzed following a 16-day depuration. Coho exposed to 347 µg/L Cd over 48hrs exhibited a reduction in freeze responses, and an extensive loss of olfaction accompanied by histological injury to the olfactory epithelium. The olfactory injury in coho exposed to 347 µg/L Cd was accompanied at the gene level by significant decreases in expression of the olfactory GPCRs and increased expression of metal and antioxidant response markers. Persistent behavioral deficits, histological injury and altered expression of a subset of olfactory biomarkers were still evident in Cd-exposed coho following a 16-day depuration in clean water. Exposure to 3.7 µg/L Cd also resulted in reduced freeze responses and histological changes to the olfactory epithelium within 48hrs of Cd exposure, although the extent of olfactory injury was less severe than observed for fish in the high Cd exposure group. Furthermore, adverse behavioral effects were present in some coho receiving the low Cd exposure following a 16-day depuration. Based on these findings, the goals for Aim 2 of my research were to investigate the toxicity of Cd on salmon olfactory function that modeled a transient sub-chronic exposure scenario. Coho were exposed to environmentally relevant concentrations of waterborne Cd (0.3, 2, and 30 µg/L) for 48hrs and 16 days, followed by a 16-day depuration. Exposures to Cd significantly and persistently altered behavioral responses towards L-cysteine and conspecific odorants. Behavioral alterations following exposure to 30 µg/L Cd were associated with increased olfactory epithelial gene expression of stress markers metallothionein and heme oxygenase, altered protein expression of olfactory signal transduction (OST) molecules critical in maintaining olfactory function, and altered gene expression of major coho odorant receptors (ORs). Exposure to Cd predominantly decreased expression of OST protein and OR molecular markers of ciliated olfactory sensory neurons (OSNs) compared to OST and OR markers of microvillus OSNs, suggesting a differential sensitivity towards Cd between the two major OSN populations. Behavioral alterations on exposure 0.3 and 2 µg/L Cd did not coincide with major histological injury or molecular changes in expression of major OST or OR markers, likely indicating disrupted signal transduction as the major mechanism underlying the olfactory behavioral dysfunction at the low-level Cd exposures. In summary, transient exposures to very low-levels of Cd can induce significant and persistent alterations of olfactory function in juvenile salmon, which could lead to increased mortality and ultimately increased stress on already threatened populations