Digital Commons Network^™

Microbial Ecology Of Active Marine Hydrothermal Vent Deposits: The Influence Of Geologic Setting On Microbial Communities, Gilberto Eugene Flores

Dissertations and Theses

The discovery of deep-sea hydrothermal vents in 1977 revealed an ecosystem supported by chemosynthesis with a rich diversity of invertebrates, Archaea and Bacteria. While the invertebrate vent communities are largely composed of endemic species and exist in different biogeographical provinces, the possible factors influencing the distribution patterns of free-living Archaea and Bacteria are still being explored. In particular, how differences in the geologic setting of vent fields influence microbial communities and populations associated with active vent deposits remains largely unknown. The overall goal of the studies presented in this dissertation was to examine the links between the geologic setting of …

Bus Replacement Modeling And The Impacts Of Budget Constraints, Fleet Cost Variability, And Market Changes On Fleet Costs And Optimal Bus Replacement Age, A Case Study, Jesse Alexander Boudart

Dissertations and Theses

Overwhelming evidence throughout the literature has shown that bus overhead and maintenance (O&M) costs increase as buses age. This has implications toward a fleet manager's decision of when one should buy, use, or sell buses to minimize total fleet costs. Unfortunately, there are uncertain market conditions associated with bus fleets that cloud the manager's ability to make appropriate decisions. Using integer programming (IP), O&M trends and changing market conditions are integrated into a model to better analyze bus fleets. Due to recent budget constraints of transit agencies, needs for a bus fleet replacement model have arisen. King County in Washington …

Social And Human Capital: Contributing Effects Of Incarceration On Neighborhoods, Jacqueline Victoria Swofford

Dissertations and Theses

Interest in human and social capital's contribution to the desistence of crime is increasingly popular amongst criminologists, economists and policy makers. However, little attention has been drawn to the influence human and social capital indicators contribute towards the relationship between the re-entry process and juvenile crime at the neighborhood level. The current study hypothesizes the existence of a mediating relationship between human and social capital indicators (2000) and the rates of receiving formerly incarcerated persons (1997-2002) and juvenile arrest (2006-08) in 92 Portland, Oregon neighborhoods. Portland, Oregon receives more formerly incarcerated persons from Oregon's state correctional facilities than any other …

Scalable And Efficient Tasking For Dynamic Sensor Networks, Thanh Xuan Dang

Dissertations and Theses

Sensor networks including opportunistic networks of sensor-equipped smartphones as well as networks of embedded sensors can enable a wide range of applications including environmental monitoring, smart grids, intelligent transportation, and healthcare. In most real-world applications, to meet end-user requirements, the network operator needs to define and update the sensors' tasks dynamically, such as updating the parameters for sensor data collection or updating the sensors' code. Tasking sensor networks is necessary to reduce the effort in programming sensor networks. However, it is challenging due to dynamics and scale in terms of number of nodes, number of tasks, and sensing regions of …

Information Processing In Two-Dimensional Cellular Automata, Martin Cenek

Dissertations and Theses

Cellular automata (CA) have been widely used as idealized models of spatially-extended dynamical systems and as models of massively parallel distributed computation devices. Despite their wide range of applications and the fact that CA are capable of universal computation (under particular constraints), the full potential of these models is unrealized to-date. This is for two reasons: (1) the absence of a programming paradigm to control these models to solve a given problem and (2) the lack of understanding of how these models compute a given task. This work addresses the notion of computation in two-dimensional cellular automata. Solutions using a …

A Computational Model Of Adaptive Sensory Processing In The Electroreception Of Mormyrid Electric Fish, Eran Agmon

Dissertations and Theses

Electroreception is a sensory modality found in some fish, which enables them to sense the environment through the detection of electric fields. Biological experimentation on this ability has built an intricate framework that has identified many of the components involved in electroreception's production, but lack the framework for bringing the details back together into a system-level model of how they operate together. This thesis builds and tests a computational model of the Electrosensory Lateral Line Lobe (ELL) in mormyrid electric fish in an attempt to bring some of electroreception's structural details together to help explain its function. The ELL is …

Runaway And Homeless Youth: Changing The Discourse By Legitimizing Youth Voice, Donald Dale Schweitzer

Dissertations and Theses

Undoubtedly, runaway and homeless youth (RHY) are one of the most vulnerable, yet underserved groups in our country. Well-meaning advocates have developed programs and services in an attempt to remedy this, yet there is little evidence of their effectiveness. Moreover, according to the research literature, a low utilization rate of current services by youth is a major concern. From a constructivist theoretical position, this study posits that the missing element is youth voice and the researcher hired formerly homeless youth to conduct the analysis of focus group data gathered from RHY who were participating in a range of services funded …

Self-Efficacy And Drinking With Friends: An Investigation Into The Drinking Behaviors Of Japanese College Students, Staci Jean Wendt

Dissertations and Theses

Recent studies have documented an alarming rate of alcohol use in Japan (Eisenback-Stangl et al., 2005; Milne, 2003; Shimizu, 2000). Indeed, permissive social and cultural norms for alcohol use exist within Japanese culture (Shimizu, 1990, 2000). Japanese college-students may be at further risk due to their developmental time period, where increases in alcohol use are typically seen. Furthermore, drinking habits formed during this time period may be difficult to alter later in life (Frone, 2003). Thus, social, developmental, and cultural factors exist to influence drinking among Japanese college students. The purpose of the current study was to investigate the drinking …

Writing Her Way To Spiritual Perfection: The Diary Of 1751 Of Maria De Jesus Felipa, Stephanie Oliver

Dissertations and Theses

Throughout the colonial period of Mexican history, cloistered nuns wrote spiritual journals at the request of their confessors. These documents were read and scrutinized, not only by the confessors, but also by others in the hierarchy of their Orders. They are important sources of study for historians in that they provide a window into the religious culture of the times and the spiritual mentality of their authors. This thesis will examine one such record, discovered in a collection of volumes at the Historical Franciscan Archive of Michoacán in Celaya, Mexico. The diary covers eleven months of 1751 in the life …

Measurement And Characterization Of Terahertz Radiation Propagating Through A Parallel Plate Waveguide, Matthew George Wachsmuth

Dissertations and Theses

As the amount of study into the terahertz (THz) region of the electromagnetic spectrum steadily increases, the parallel plate waveguide has emerged as a simple and effective fixture to perform many experiments. The ability to concentrate THz radiation into a small area or volume enables us to analyze smaller samples and perform more repeatable measurements, which is essential for future research. While the fundamental physics of PPW transmission are understood mathematically, the practical knowledge of building such a fixture for the THz domain and taking measurements on it with a real system needs to be built up through experience. In …

Investigating Future Variation Of Extreme Precipitation Events Over The Willamette River Basin Using Dynamically Downscaled Climate Scenarios, Andrew Jason Halmstad

Dissertations and Theses

One important aspect related to the management of water resources under future climate variation is the occurrence of extreme precipitation events. In order to prepare for extreme events, namely floods and droughts, it is important to understand how future climate variability will influence the occurrence of such events. Recent advancements in regional climate modeling efforts provide additional resources for investigating the occurrence of extreme events at scales that are appropriate for regional hydrologic modeling. This study utilizes data from three Regional Climate Models (RCMs), each driven by the same General Circulation Model (GCM) as well as a reanalysis dataset, all …

Scratched Petroglyphs In The Bennett Hills, Idaho, Karla Lucille Hambelton

Dissertations and Theses

This study examines rock art sites containing scratched petroglyphs in the Bennett Hills, Idaho. Despite their research potential, scratched petroglyphs have received little attention in rock art research or literature. This study contributes valuable data to scratched rock art research and the corpus of rock art research in general. Two samples of ten scratched petroglyph sites were examined and recorded for a total of twenty petroglyph sites. Using formal and contextual research methods, multiple attributes of scratched petroglyphs are identified and analyzed. The formal qualities of scratched petroglyphs are examined to define the extent and to characterize the motif assemblage. …

Ce-Qual-W2 Water Quality And Fish-Bioenergetics Model Of Chester Morse Lake And The Cedar River, Vanessa I. Wells

Dissertations and Theses

Many communities are currently seeking to balance urban water needs with preservation of sensitive fish habitat. As part of that effort, CE-QUAL-W2, a hydrodynamic and temperature model, was developed for Chester Morse Lake and the lower Cedar River, WA. Chester Morse Lake is approximately 10 km long with a maximum depth at full pool of 40 m. The Cedar River model started immediately downstream of the Chester Morse dam and ended 21 km downstream at Landsburg, where drinking water is diverted for the City of Seattle. This water quality model was coupled with a fish habitat and bioenergetics model for …

Student Approaches To Combinatorial Enumeration: The Role Of Set-Oriented Thinking, Elise Nicole Lockwood

Dissertations and Theses

Combinatorics is a growing topic in mathematics with widespread applications in a variety of fields. Because of this, it has become increasingly prominent in both K-12 and undergraduate curricula. There is a clear need in mathematics education for studies that address cognitive and pedagogical issues surrounding combinatorics, particularly related to students' conceptions of combinatorial ideas. In this study, I describe my investigation of students' thinking as it relates to counting problems. I interviewed a number of post-secondary students as they solved a variety of combinatorial tasks, and through the analysis of this data I defined and elaborated a construct that …

High Speed Wireless Networking For 60ghz, Candy Yiu

Dissertations and Theses

This thesis examines the problem of providing high data-rate wireless connectivity to users in indoor environments. The goal is to be able to reach Gbps/user rates even when there are multiple users present. The technology that we study is to use the 60 GHz spectrum whose special propagation properties make it ideally suited to this task. The approaches developed include using multiple spatially distributed smart antennas in a room or multiple co-located antennas to provide coverage where needed and when needed. All the antennas are connected to a single access point which allows us to dynamically change spectrum and link …

Biological Erosion Of Marine Habitats And Structures By Burrowing Crustaceans, Timothy Mathias Davidson

Dissertations and Theses

Marine bioeroders, borers, and burrowers can have drastic effects to marine habitats and facilities. By physically altering the structure of marine habitats, these organisms may elicit ecosystem-level effects that cascade through the community. While borer damage is typically restricted to a few substratum types, burrowing isopods in the genus Sphaeroma attack a diversity of substrata in tropical and temperate systems. My dissertation examined how boring sphaeromatid isopods affect coastal habitats (saltmarshes, mangroves) and other estuarine substrata as well as marine structures. I used a combination of lab and mensurative field experiments to quantify the effects of boring by isopods and …

Molecular Genetic Analysis Of Creld1 In Patients With Heterotaxy Disorder, Samaneh Zhian

Dissertations and Theses

Heterotaxy refers to the abnormal arrangement of internal organs in relation to each other. Model organism studies have shown that functions of more than eighty genes are required for normal asymmetric left-right organ development. CRELD1 has been shown to be necessary for proper heart development and mutations in CRELD1 are known to increase risk of cardiac atrioventricular septal defects (AVSD). AVSD is the most common form of heart defect associated with heterotaxy, and we have previously shown that some individuals heterotaxy-related AVSD have mutations in CRELD1.

Therefore, we propose to examine the CRELD1 gene in a large sample of …

Chinese Merchants And Race Relations In Astoria, Oregon, 1882 - 1924, Aaron Daniel Coe

Dissertations and Theses

A large wave of Chinese immigrants came to the United States in the second half of the nineteenth century. Employment, mainly in the salmon-canning industry, drew thousands of them to coastal Astoria, Oregon. Taking the period between the first Chinese Exclusion Act in 1882 and the Immigration Act of 1924, this thesis focuses on the Chinese merchants in Astoria and their importance for our understanding of race relations in the town during these years. Specifically, the merchants help to make sense of how the Chinese related to the local white population, as different sources suggest different trends of amiability and …

Early Childhood Inclusion: Teacher Perception Of The Supports Needed To Fully Include Children With Special Needs, Meredith Villines

Dissertations and Theses

Inclusion of children with disabilities in early childhood settings remains a goal for many early care and education centers and professionals. In this study, the perceptions of supports needed to accomplish this goal were examined. Early childhood teachers from a university-based child care center, which is inspired by the schools in Reggio Emilia, Italy, were interviewed and asked to explore their feelings and thoughts on fully including children with disabilities in their classrooms. An examination of their perceptions led to the identification of four major themes: a) everyone is valuable in the classroom community, b) additional training is needed, c) …

A Functional Approach To Memory-Safe Operating Systems, Rebekah Leslie

Dissertations and Theses

Purely functional languages--with static type systems and dynamic memory management using garbage collection--are a known tool for helping programmers to reduce the number of memory errors in programs. By using such languages, we can establish correctness properties relating to memory-safety through our choice of implementation language alone. Unfortunately, the language characteristics that make purely functional languages safe also make them more difficult to apply in a low-level domain like operating systems construction. The low-level features that support the kinds of hardware manipulations required by operating systems are not typically available in memory-safe languages with garbage collection. Those that are provided …

Population Structure Of Island-Associated Pantropical Spotted Dolphins (Stenella Attenuata) In Hawaiian Waters, Sarah Shelby Courbis

Dissertations and Theses

Understanding gene flow, diversity, and dispersal patterns is important for predicting effects of natural events and anthropogenic activities on dolphin populations. With the very recent exceptions of false killer whales (Pseudorca crassidens), spinner dolphins (Stenella longirostris), and common bottlenose dolphins (Tursiops truncatus), Hawaiian odontocete species are managed as single stocks within the U.S. Hawaiian Exclusive Economic Zone. These exceptions are a result of recent studies that have indicated that some species have populations that show fidelity to individual islands or groups of islands, resulting in genetic differentiation, often with management implications. The first part …

The Technological Role Of Bone And Antler Artifacts On The Lower Columbia: A Comparison Of Two Contact Period Sites, Kristen Ann Fuld

Dissertations and Theses

This thesis explore the technological role of bone and antler artifacts from two contact period southern Northwest coast archaeological sites, the Cathlapotle site (45CL1) and the Meier site (35CO5). Technological measures of sedentism are based on lithics, and predict residential sedentism promotes technological expediency in hunter-gatherers (Parry and Kelley 1987). Cathlapotle and Meier lithic assemblages consist of expedient and opportunistic assemblages and raw material stockpiles, with the exception of highly curated projectile points and endscrapers (Hamilton 1994). The expectation that residential sedentism promotes technological expediency in hunter-gatherers was tested on the Cathlapotle and Meier bone and antler artifact assemblages in …

A Self-Configurable Architecture On An Irregular Reconfigurable Fabric, Avinash Amarnath

Dissertations and Theses

Reconfigurable computing architectures combine the flexibility of software with the performance of custom hardware. Such architectures are of particular interest at the nanoscale level. We argue that a bottom-up self-assembled fabric of nodes will be easier and cheaper to manufacture, however, one has to make compromises with regards to the device regularity, homogeneity, and reliability. The goal of this thesis is to evaluate the performance and cost of a self-configurable computing architecture composed of simple reconfigurable nodes for unstructured and unknown fabrics. We built a software and hardware framework for this purpose. The framework enables creating an irregular network of …

Using Curriculum-Based Measures To Predict Math Performance On A Statewide Assessment, Keri F. Menesses

LSU Doctoral Dissertations

One hundred forty-six students in third, fourth, and fifth grades completed two types of curriculum-based measurement (CBM) math probes, math computation and math concepts/ applications, in the winter and spring. The relationship between scores on the math probes and scores on the math portion of the Louisiana statewide assessments were analyzed by computing correlation coefficients and conducting multiple regression analyses. Both types of probes were significantly correlated with test outcomes, yet the concepts/applications probes were stronger predictors of test performance. The diagnostic accuracy of the probes was determined using receiver operating characteristic (ROC) curve analyses, which established cut scores that …

Learning And Teaching Conducting Through Musical And Non-Musical Skills: An Evaluation Of Orchestral Conducting Teaching Methods, Jose Mauricio Valle Brandao

LSU Doctoral Dissertations

The current state of conducting as an academic and professional pursuit shows a plethora of conventional traditions and techniques that are accepted without question, but a dearth of ideas and approaches that will develop the skills essential to producing an effective conductor. This profile is especially apparent in the field‘s literature. This monograph will compile a list of these titles and annotate each one, in order to determine the common threads that run between them. This information will be distilled into categories, identifying levels of approach and target audience. Evaluation of these data may lead to a discovery that many …

Implementing Lean In Healthcare Warehouse Operations - Evaluation Of 5s Best Practice, Sanjith Venkateswaran

LSU Master's Theses

Lean strategies in healthcare aim at improving patient throughput, reducing medication errors, redesigning work flow, improving patient safety, and reducing cycle time. Documented studies to improve healthcare’s warehouse operation are not common in the literature. Managing types of medical supplies has always been a priority due to demand uncertainties and the risk of shortages that would profoundly affect patient safety. This study showcases two implementation approaches for the Lean tool 5S (Hybrid and Traditional) conducted in three different hospitals’ central warehouses at Ochsner Health System. These warehouses store similar medical products with over 1000 types of supplies (e.g. syringes, gloves, …

Adequacy Of Diabetes Care For Older U.S. Rural Adults: A Cross-Sectional Population Based Study Using 2009 Brfss Data, M. Nawal Lutfiyya, Joel E. Mccullough, Lori Mitchell, L. Scott Dean, Martin S. Lipsky

Community Health Faculty Publications and Presentations

Background: In the U.S. diabetes prevalence estimates for adults ≥ 65 years exceed 20%. Rural communities have higher proportions of older individuals and health disparities associated with rural residency place rural communities at risk for a higher burden from diabetes. This study examined the adequacy of care received by older rural adults for their diabetes to determine if older rural adults differed in the receipt of adequate diabetes care when compared to their non-rural counterparts.

Methods: Cross-sectional data from the 2009 Behavioral Risk Factor Surveillance Survey were examined using bivariate and multivariate analytical techniques.

Results: Logistic regression analysis revealed that …

Paclitaxel Induces Thrombomodulin Downregulation In Human Aortic Endothelial Cells, Huang-Joe Wang, Te-Ling Lu, Haimei Huang, Huey-Chun Huang

The Texas Heart Institute Journal

Patients with paclitaxel-eluting stents are at risk of developing stent thrombosis upon premature discontinuation of dual antiplatelet therapy. In this study, we set out to clarify whether paclitaxel can modulate thrombomodulin expression in human aortic endothelial cells. Human aortic endothelial cells were stimulated with paclitaxel. Methoxyphenyl tetrazolium inner salt cell viability assay, Western blot analysis, real-time polymerase chain reaction, and immunohistochemical assay were performed. In human aortic endothelial cells, paclitaxel (10(-5) to 10(-9) mol/L) treatment for 13 hours caused significant cytotoxicity at drug concentrations greater than 10(-7) mol/L. Paclitaxel (10(-5) to 10(-9) mol/L) treatment for 5 hours downregulated thrombomodulin expression …

Internal Medicine Problems As They Present To The Cardiologist, Ira Martin Grais

The Texas Heart Institute Journal

No abstract provided.

Cardiac Surgery: A Century Of Progress, Allen B Weisse

The Texas Heart Institute Journal

Well into the first decades of the 20th century, medical opinion held that any surgical attempts to treat heart disease were not only misguided, but unethical. Despite such reservations, innovative surgeons showed that heart wounds could be successfully repaired. Then, extracardiac procedures were performed to correct patent ductus arteriosus, coarctation of the aorta, and tetralogy of Fallot. Direct surgery on the heart was accomplished with closed commissurotomy for mitral stenosis. The introduction of the heart-lung machine and cardiopulmonary bypass enabled the surgical treatment of other congenital and acquired heart diseases. Advances in aortic surgery paralleled these successes. The development of …