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Characterization Of The Effects Of The Human Head On Communication With Implanted Antennas, Michael A. Pecoraro

Theses

Cranially implanted sensors and electrodes have been used in practice for several years; their applications range from the recording of neural signals for use in Brain-Computer Interfaces to help the disabled, to the treatment of diseases and conditions ranging from Parkinson's disease, multiple sclerosis, depression, etc. Current communication methods with implants, however, are lacking; they run the gamut from physical, percutaneous connections that increase the risk of infection, to wireless links that are slow and uncomfortable for patients. The present work focuses on the characterization of the effects of the human head on communication with cranially implanted antennas for its …

Elliptic Curves And Cryptography, Senorina Ramos Vazquez

Master's Theses

In this expository thesis we study elliptic curves and their role in cryptography. In doing so we examine an intersection of linear algebra, abstract algebra, number theory, and algebraic geometry, all of which combined provide the necessary background. First we present background information on rings, fields, groups, group actions, and linear algebra. Then we delve into the structure and classification of finite fields as well as construction of finite fields and computation in finite fields. We next explore logarithms in finite fields and introduce the Diffie-Hellman key exchange system. Subsequently, we take a look at the projective and affine planes …

Microelectromechanical Systems Coulter Counter For Cell Monitoring And Counting, James D. Benson, Yifan Wu, John K. Critser, Mahmoud Almasri

Faculty Articles, Papers, and Other Scholarship

This note describes the design, fabrication, and testing of a novel microelectromechanical systems Coulter counter. The Coulter counter will be used to detect and monitor impedance changes of cells as a function of time in response to different experimental extracellular environments. The device consists of SU-8 (negative photoresist ) microchannels, vertical electroplated electrodes, polydimethylsiloxane cover, and is divided into a passive mixing region, a focusing region using negative dielectrophoretic forces, and a measuring region defined by multiple electroplated electrode pairs. The devices were tested using both microbeads in saline water and fibroblast cells in phosphate buffered saline solution. The results …

Determination Of The Economic Optimal Cycle Length For Major Sugarcane (Saccharum Spp.) Varieties In Louisiana, Juan Steer Nunes

LSU Master's Theses

The general objective of the study was to determine the economically optimal crop cycle length for major sugarcane varieties currently being produced in Louisiana. The specific objectives of the project included the specification of the mathematical acreage relationships which directly impact the production of a vegetatively propagated perennial crop in a whole farm context; the development of producer decision rules to be used to determine breakeven sugar levels on third stubble sugarcane crops for major varieties in the state; the evaluation of the impact of changes in production factors on developed crop replacement rules; and the optimal cycle length for …

Modeling The Impacts Of Pulsed Riverine Inflows On Hydrodynamics And Water Quality In The Barataria Bay Estuary, Anindita Das

LSU Doctoral Dissertations

Eutrophication and coastal wetland loss are the major environmental problems affecting estuaries around the world. In Louisiana, controlled diversions of the Mississippi River water back into coastal wetlands are thought to be an important engineering solution that could reverse coastal land loss. There are concerns, however, that freshwater diversions may increase nutrient inputs and create severe eutrophication problems in estuaries and wetlands adjacent to the diversion sites. My dissertation research concerns modeling the effects of the observed and hypothetical freshwater diversion discharges on the hydrodynamics, salinity and water quality in the Barataria estuary, a deltaic estuary in south Louisiana. This …

Volcanological And Petrogenetic Characteristics Of Komatiites Of The 3.3 Ga Saw Mill Complex, Weltevreden Formation, Barberton Greenstone Belt, South Africa, Matthew Stephen Huber

LSU Master's Theses

The Saw Mill Complex (SMC) is a 1275 m thick layered komatiitic sequence in the 3.3 Ga Weltevreden Formation, uppermost stratigraphic unit of the Onverwacht Group in the northern part of the Barberton Greenstone Belt, South Africa. A series of ultramafic complexes in the Weltevreden Formation have been interpreted as layered ultramafic intrusions, consisting of thick, layered ultramafic units of peridotite, pyroxenite, dunite, and gabbro. However, recent work on the Pioneer complex of the Weltevreden Formation has demonstrated an extrusive origin of komatiites and tuffs. The Weltevreden Formation has been less studied than other Onverwacht Group units. It is likely …

An Economic Analysis Of The Costs Of Alternative Sugarcane Fallow Weed Control Programs, José Rodolfo Mite Cáceres

LSU Master's Theses

Economic research was conducted to present estimates of costs per acre associated with fallow sugarcane weed control programs for Louisiana in 2010. The 2010 projected costs are associated with the various phases of sugarcane fallow using different machinery, implements, and weed control practices followed by most growers in the main sugarcane production area of Louisiana. For bermudagrass and johnsongrass weed control treatments, the herbicides applied were Roundup Original Max at 46 oz/A, generic glyphosate at 64 oz/A, DuPont K4 60DG, Trifluralin 4EC at 4 qt/A, and EPTC at 3.5 pt/A. Purple nutsedge weed control treatments included Roundup Original Max at …

Oregon's Fish And Wildlife In A Changing Climate, Mark A. Hixon, Stanley V. Gregory, W. Douglas Robinson, C. Scott Baker, Harold P. Batchelder, Clinton Epps, Tiffany S. Garcia, Susan M. Haig, Ricardo M. Letelier, David A. Lytle, Bruce A. Menge, Jeffery C. Miller, David L.G. Noakes, William T. Peterson, James M. Rice, Steven S. Rumrill, Carl B. Schreck, Robert M. Suryan, Mark D. Sytsma, Angelicque E. White

Center for Lakes and Reservoirs Publications and Presentations

Chapter 7 in: The Oregon Climate Change Assessment Report

Oregon's fish and wildlife include animals on land, fish and other species in rivers and lakes, and various kinds of sea life in estuaries and coastal ocean. Oregon is one of the most ecologically diverse states in the country. The state’s robust biodiversity, some of which is already threatened or endangered -- inhabits complex and dynamic ecosystems that we have only begun to understand, let alone examine in terms of climate change.It is clear that the abundance and distribution of species are shifting already and will shift more rapidly as habitats …

Hydroacoustic Survey And Point Sampling Of Macrophytes In Diamond Lake 2009, Joseph Eilers, Benn Eilers, Mark D. Sytsma, Rich Miller

Center for Lakes and Reservoirs Publications and Presentations

MaxDepth Aquatics, Inc. was contracted to conduct a hydroacoustic survey of macrophyte distribution in Diamond Lake in 2009. The survey essentially repeated surveys conducted in 2002 and 2007, allowing for a detailed assessment of conditions in 2009 and comparisons among previous years. In addition, Portland State University was contracted to conduct a depth stratified random point sample survey of macrophyte species presence and absence. The point sample survey was similar to surveys conducted in 2005 and 2007. The results of the 2009 hydroacoustic survey showed that macrophytes were widely distributed throughout the lake at depths less than 8 meters, although …

The Effects Of Self-Assessment On Student Learning Of Mathematics, Daniel James Hotard

LSU Master's Theses

Self-assessment can be defined as students judging their own work, based on evidence and explicit criteria, for the purpose of improving future performance. Many researchers agree that implementation of student self-assessment in the classroom is an important tool for improving academic performance and self-efficacy. In this thesis, I investigated the effects of student self-assessment on learning gains of 81 alternative high school Algebra I students. This study took place over the course of two units of instruction. Classes were divided into two groups. One group of students utilized rubrics to self-assess their own work for the first unit, while the …

Metamorphic Rocks In The Sawtooth Mountains, Idaho, Usa: A Window Into The Precambrian Basement Of Southwest Laurentia, Kyle Michael Metz

LSU Master's Theses

The western North American craton consists of a mosaic of Precambrian basement terranes that developed through episodes of microcontinent collision and magmatic arc accretion. Defining the extent and boundaries of these terranes is critical to deciphering the Precambrian development of Laurentia. The poorly exposed Selway terrane occurs between the Archean Wyoming province and the Neoproterozoic rifted margin of Laurentia. A rare exposure of Precambrian metamorphic rocks, the Sawtooth Metamorphic Complex (SMC), crops out over 33 km2 in the Sawtooth Mountains of Idaho, USA, and potentially provides a window into the deep crust of the region. Field mapping, petrographic analyses, and …

Highly Efficient Selection, Enumeration, Enrichment, And Molecular Profiling Of Low-Abundance Biological Cells, Udara R. Dharmasiri Rasika Dharmasiri

LSU Doctoral Dissertations

After brief overviews of low-abundance cell selection techniques in chapter 1 and circulating tumor cells in chapter 2, this dissertation initially focuses on the development of aptamer incorporated high-throughput microfluidic techniques to select rare circulation prostate cancer cells (LNCaP) directly from whole blood with subsequent quantification of these rare cells using a non-labeling approach. Then, I extended the technology to environmental samples in an effort around time, sensitivity, and portability of traditional groundwater assessment. As a model bio- pathogen, E. coli O157:H7 was chosen due to its toxicity and its adverse impact on recreational waters. Low-abundance (<100 cells mL-1) E. coli O157:H7 cells were isolated and enriched from environmental water samples using a microfluidic chip that its capture beds were covalently decorated with E.coli O157:H7 specific polyclonal antibodies. The selected cells were enumerated using RT-qPCR technique. Finally, I have integrated HTMSU with electrokinetic enrichment microfluidic unit for performance of single recombinant low-abundance CTC cell-based assay. A series of analytical processes were carried out, including immunoaffinity selection of rare CTCs, quantification of selected cells via conductivity impedance and electrophoretic enrichment of selected cells for PCR/LDR/CE interrogation for detection of low-abundance point mutations in genomic DNA.

Fabrication Of Receptor-Modified Microfluidic Surfaces For Applications In Glycoprotein Screening, Jennifer Macalindong De Guzman

LSU Doctoral Dissertations

Glycoproteins have long been identified to have a profound association with human pathological processes, and they are much sought after as potential biomarkers to aid in the early diagnosis and clinical prognosis of cancers and diseases. There is currently high demand for high-throughput and low–limit–of–detection techniques that can afford profiling of the glycoproteome. Micro-total analysis systems (µTAS) based on microfluidics have the potential to fulfill these requirements, but in order to reduce the complexity of the protein pool, the µTAS devices must contain a pre-isolation and enrichment component. The research project undertaken here involved derivatization of microfluidic …

The Effect Of War On Art: The Work Of Mark Rothko, Elizabeth Leigh Doland

LSU Master's Theses

My goal for this thesis was to adequately illustrate the effect war can have on art and artists. I chose to single out one particular artist who lived and worked during a time of war and explore his life and work. My choice of artist was not random: I chose an individual who was particularly concerned about his external environment, and was active in the political and social issues of the time. My subject is Mark Rothko, a Russian-Jewish artist who immigrated from Russia as a boy and spent his life in the hotspot of artistic inspiration, New York City. …

Effective Lesson Planning: Field Trips In The Science Curriculum, Cynthia Rau Rieger

LSU Master's Theses

Science field trips can positively impact students and motivate them into future studies in various science fields. However, if a field trip is not executed properly, it can result in a loss of valuable educational time and could promote misconceptions in the students. This study was undertaken to determine if a classroom lesson before an out-of-the-classroom activity would affect learner gain more or less than a lesson after the activity. The students were divided into two different groups. The groups differed based on the sequence of activities that they received. The activities involved in this study included visiting an immersive …

Is A Student's Conceptual Knowledge Affected By Their Vocabulary Instruction?, Daniel C. Cox

LSU Master's Theses

The following paper explores the possible relationship between the manner in which a student is taught vocabulary in a high school physics classroom and the ability of those students to correctly answer physics conceptual questions. Two high school physics classes taught by the same teacher (eight or nine students in one and seventeen in the other) received identical instruction throughout multiple units with the exception of vocabulary instruction. Differences were observed in the students’ ability to correctly answer conceptual questions in only one topic, heat. The students did not get better at answering a question concerning a phase change or …

Comprehensive Study Of Parameters For Volumetric Modulated Arc Therapy (Vmat) Treatment Planning, Catharine Elizabeth Talbert

LSU Master's Theses

Volumetric modulated arc therapy (VMAT) is a rotational IMRT technique that uses a radiotherapy linear accelerator gantry with a dynamic MLC, variable dose rate, and variable gantry speed. These new degrees of freedom of VMAT delivery introduced complexities for treatment planning, and Pinnacle3 SmartArc treatment module was recently developed as a solution. However, it was unclear how varying each SmartArc parameter affected the resulting plan quality. The purpose of this study was to systematically examine all planning parameters and quantify the effect of varying each on the quality of a reference plan. Parameters were separated into two categories: commissioning parameters …

Quantum Light For Quantum Technologies, William Nicholas Plick

LSU Doctoral Dissertations

In this thesis we will theoretically investigate three potentially useful physical systems, after first developing the theoretical framework necessary for studying them. First, we will study the multiphoton absorption properties of maximally path entangled number (N00N) states. This is directly relevant to quantum lithography, and beating the Rayleigh diffraction limit. Next, we will develop a new scheme for quantum interferometry: dubbed coherent-light boosted super-sensitive quantum interferometry, which has the potential to reach below the shot noise limit for high photon fluxes, and requires no esoteric detection protocol, or technological elements that have yet to be developed. Finally we propose a …

Speciation Of Heavy Metals In Disturbed And Undisturbed Sediments From Atchafalaya Bay, Houma Navigation Canal, And Southwest Pass, Louisiana, Amanda Jo Zimmerman

LSU Master's Theses

In coastal Louisiana it is common to use dredge spoil to build marshland that has been lost due to a variety of factors. Under various conditions such as deposition in a drained oxygenated environment, metals in the spoil can become more bioavailable posing a threat to the ecosystem. This study compares metal availability in natural and dredged sediments to determine what changes occur in nature. Forty four samples from three locations, Atchafalaya Delta, Houma Navigation Canal, and Southwest Pass, were analyzed for 13 common elements with known or potentially harmful health effects; Al, As, Ba, Be, Cd, Cr, Co, Cu, …

Computer Simulation Of Ion-Induced Nucleation In The Presence Of Single Ions And Ion Pairs, Samuel Keasler

LSU Doctoral Dissertations

Atmospheric aerosol particles play an important role in climate and human health. Despite their importance, the mechanisms of their formation are still poorly understood. Ion-induced nucleation may play a role in the process, but details are lacking about how the nucleation rate depends on the size, charge, and number of ions in the cluster. In order to better understand the role that ions might play in new particle formation, we have performed a series of AVUS-HR simulations of the water nucleation in the presence of both single ions and ion pairs. These simulations have shown that the location of the …

The Adoption Of Best Management Practices In The Louisiana Crawfish Industry, Narayan P. Nyaupane

LSU Master's Theses

Agricultural production can have result in environmental deterioration in cases where proper management practices have not been implemented. Louisiana, one of the tropical states, has a significant agricultural base with more than 1,600 farmers raising crawfish. Large volumes of waste water containing environmental pollutants result significant environmental problem in the state. Voluntary adoption of a number of best management practices (BMPs) that are considered to be environmentally and economically beneficial is encouraged in Louisiana. The major objectives of this study are to investigate farmer adoption of 18 selected Natural Resources Conservation Service (NRCS) cost share eligible BMPs and the reasons …

The Effects Of Salinity On Nitrogen Cycling In Wetland Soils And Sediments Of The Breton Sound Estuary, La, Brett Whitfield Marks

LSU Master's Theses

Wetlands in the coastal zone are slowly becoming more saline under rising sea level over the long-term. However, there are a number of events in the coastal environment which lead to quick and temporary changes in the salinity of coastal marshes. Seawater driven inland from storm surge can significantly increase salinity in oligohaline wetlands over the short-term (weeks). Recent large-scale efforts to restore coastal wetlands in Louisiana have utilized Mississippi River surface water diversions to re-introduce freshwater into coastal marshes, decreasing the salinity of coastal marshes. We examined the effect of salinity changes on two important nitrogen cycling processes, potential …

The Theoretical Learning Impact Of A Summer Engineering Program Curriculum For Underrepresented Middle School Students, Vaneshette Teshawn Henderson

LSU Doctoral Dissertations

This mixed methods, exploratory and confirmatory study was designed to evaluate the theoretical learning impact of a innovative summer engineering program curriculum would have on its audience, middle school minority students. Several theories were used to develop the innovative curriculum including Human Constructivism, cultural learning styles of African Americans, visual spatial learning and graphic design learning. This study was completed in two phases: evaluation of existing middle school summer engineering program curriculum for best practices and development of innovative curriculum and expert evaluation of the innovative curriculum. Three existing programs from across the country participated in this study. Five engineering …

University Admissions Officers' Perceptions Of Student Performance Within The International Baccalaureate Diploma Program, Emily Trabona Tarver

LSU Doctoral Dissertations

This qualitative study sought to provide a general perception of admissions offices of secondary institutions have toward the Diploma Program through a grounded theory approach. The first goal of the study investigated the nature of credit awards for a student’s high school academic performance. Specific attention was paid to the processes institutions use for determining credit awards, policies associated with credit awards, and perceptions related credit awards. The second goal investigated admissions policies, processes, and perceptions associated with credit awards and the DP specifically. Finally, the third goal sought to illustrate the development and/or changes in the perceptions and actions …

Investigating The Effectiveness Of Informal Science Education Through Quantitative And Qualitative Analysis: Ocean Commotion, Catherine Angela Sutera

LSU Master's Theses

Informal science education serves as an important source for science education for both individuals and school groups. However, the effectiveness of school visits to informal science education events outside of either museums or science centers has received little investigation. This study explores the short-term effects of a hands-on learning experience on students’ attitude and content knowledge. Specifically, it investigates the impact of Ocean Commotion, a one-day event where exhibitors present information and hands-on demonstrations about marine environments and products, especially those important to Louisiana. Pre-tests were utilized to document students’ initial knowledge of and attitude toward wetlands and the ocean, …

Improving Software Quality Using An Ontology-Based Approach, Yixin Luo

LSU Doctoral Dissertations

Ensuring quality in software development is a challenging process. The concepts of anti-pattern and bad code smells utilize the knowledge of reoccurring problems to improve the quality of current and future software development. Anti-patterns describe recurring bad design solutions while bad code smells describe source code that is error-free but difficult to understand and maintain. Code refactoring aims to remove bad code smells without changing a program’s functionality while improving program quality. There are metrics-based tools to detect a few bad code smells from source code; however, the knowledge and understanding of these indicators of low quality software are still …

The Achievement Of Business Education Students On High School Core Subjects, Mohd Khata Bin Jabor

LSU Doctoral Dissertations

The importance of academic courses taken during high school has been well documented. It could determine the students’ achievement in high school, affect the students’ ability to transition to postsecondary education and expand the students’ choice of postsecondary majors and degree options (Laird, Chen, & Levesque, 2006). This study examined whether enrollment in business education is related to achievements in high school core subjects. The rationale for the study is to determine if business education contributes to the academic achievement of high school students. This study used the data from the National Assessment of Educational Progress (NAEP) High School Transcript …

The Influence Of Program Participation In Business Education Courses On Standardized Test Performance Among Secondary Students In Louisiana, Debra A. Wilkerson

LSU Doctoral Dissertations

The primary purpose of this study was to compare the academic achievement, as measured by scores on the English and math portions of the Graduate Exit Examination (GEE), of public high school students in Louisiana by whether or not they were identified as business education students. The GEE is a high-stakes test that is administered to high school students in Louisiana. Students must pass specific portions of the test to obtain a diploma. Academic achievement data on the GEE was obtained from the Louisiana Department of Education. The sample for the study was all 10th and 11th grade students enrolled …

Quantifying The Impact Of Data Quality On Searches For Gravitational Waves From Binary Coalescing Systems With Ligo, Jacob Peter Slutsky

LSU Doctoral Dissertations

Gravitational waves are ripples in space-time itself, predicted by Einstein's General theory of relativity, which propagate at the speed of light and are not scattered or extinguished by passing through matter almost at all. In particular, the gravitational waves from the coalescences of binary systems of compact objects, such as neutron stars and black holes, are exciting prospects for observation. The Laser Interferometer Gravitational-wave Observatory experiment intends to make the _x000C_first direct measurement of gravitational waves, and use the results to uncover new astrophysics. These observations will not be limited by extinction from dust and gas, and will probe astrophysical …

Model-Based Nonlinear Control Of Active Tilting-Pad Bearings, An Wu

LSU Doctoral Dissertations

A promising mechanical bearing candidate for active operation is the tilting-pad bearing. The proposed active tilting-pad bearing has linear actuators that radially translate each pad. The use of feedback control in determining the actuator forces allows for the automatic, continuous adjustment of the pad position during the operation of the rotating machine. In the first part of the dissertation, we develop a nonlinear dynamic model of the active bearing system. The hydrodynamic force produced by the fluid film is modeled as a nonlinear, squeeze-film damper plus repellent spring. A model-based nonlinear controller is then designed to exponentially regulate the rotor …