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Metamorphic Rocks In The Sawtooth Mountains, Idaho, Usa: A Window Into The Precambrian Basement Of Southwest Laurentia, Kyle Michael Metz 2010 Louisiana State University and Agricultural and Mechanical College

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 ...


A Characterization Of Near Outer-Planar Graphs, Tanya Allen Lueder 2010 Louisiana State University and Agricultural and Mechanical College

A Characterization Of Near Outer-Planar Graphs, Tanya Allen Lueder

LSU Master's Theses

This thesis focuses on graphs containing an edge whose removal results in an outer-planar graph. We present partial results towards the larger goal of describing the class of all such graphs in terms of a finite list of excluded graphs. Specifically, we give a complete description of those members of this list that are not 2-connected or do not contain a subdivision of a three-spoke wheel. We also show that no members of the list contain a five-spoke wheel.


Highly Efficient Selection, Enumeration, Enrichment, And Molecular Profiling Of Low-Abundance Biological Cells, Udara R. Dharmasiri Rasika Dharmasiri 2010 Louisiana State University and Agricultural and Mechanical College

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.


Effects Of Habitat Structural Complexity On Nekton Assemblages: Lab And Field Observations In Southern Louisiana, Austin T. Humphries 2010 Louisiana State University and Agricultural and Mechanical College

Effects Of Habitat Structural Complexity On Nekton Assemblages: Lab And Field Observations In Southern Louisiana, Austin T. Humphries

LSU Master's Theses

Greater structural complexity is often associated with more diverse and abundant species assemblages. Biogenic reefs formed by the eastern oyster (Crassostrea virginica) are structurally complex in nature and have been recognized for their potential habitat value in estuarine systems along the Atlantic and Gulf of Mexico coasts. To determine how the structural complexity of newly created oyster reefs may influence the abundance and distribution of species, three objectives were established. First, to examine spatial and temporal patterns of nekton use at newly created oyster reefs, as well as the impact of wave exposure, six paired oyster reef and mud-bottom treatments ...


Fabrication Of Receptor-Modified Microfluidic Surfaces For Applications In Glycoprotein Screening, Jennifer Macalindong De Guzman 2010 Louisiana State University and Agricultural and Mechanical College

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 ...


Introgression, Health, And Condition Of Florida, Northern, And Fx Hybrid Largemouth Bass In Louisiana Water Bodies, Melissa Ann Fries 2010 Louisiana State University and Agricultural and Mechanical College

Introgression, Health, And Condition Of Florida, Northern, And Fx Hybrid Largemouth Bass In Louisiana Water Bodies, Melissa Ann Fries

LSU Master's Theses

Since 1982, the Louisiana Department of Wildlife and Fisheries (LDWF) has stocked Florida-strain largemouth bass (FLMB; Micropterus salmoides floridanus) to incorporate Florida alleles into native populations (NLMB; M. s. salmoides) and enhance recreational fishing opportunities. I collected habitat data and largemouth bass samples from 12 LDWF stocked reservoirs and disconnected oxbow lakes to examine the relationships between reservoir characteristics, genetic identity, relative weight (Wr), liver somatic index (LSI), parasite loads, and back-calculated length-at-age. I examined the relationships between water body and genetic identity with Wr, LSI, and back-calculated length-at-age by ANOVA. Parasite loads were analyzed with ordinal regression. Principle component ...


Patterns Of Habitat Suitability And Abundance Trends Of Current And Candidate Coastal Fish Species Of Concern In Louisiana, Elin Rose Sandy 2010 Louisiana State University and Agricultural and Mechanical College

Patterns Of Habitat Suitability And Abundance Trends Of Current And Candidate Coastal Fish Species Of Concern In Louisiana, Elin Rose Sandy

LSU Master's Theses

Louisiana’s estuaries and coastal waters play an important role in providing habitat for several estuarine-dependent species and also serve as a nursery for the juveniles of several other species. The current rate of land loss in Louisiana and the decline of estuarine-dependent species force us to improve our understanding of the recruitment of these species into Louisiana’s estuaries. Habitat suitabilities were developed for several fish species of concern (SOC) and other estuarine-dependent species across three environmental gradients, abundance patterns were developed for seasons, five-year intervals, and coastal study areas (CSAs). Chi-square analyses and ANOVAs were then used to ...


Influences On Public Support For Green Infrastructure: An Examination Of Urban Wetland Restoration In Post-Katrina New Orleans, Lynette C. Overholser 2010 Louisiana State University and Agricultural and Mechanical College

Influences On Public Support For Green Infrastructure: An Examination Of Urban Wetland Restoration In Post-Katrina New Orleans, Lynette C. Overholser

LSU Master's Theses

The research examines patterns of likely support for urban wetland restoration in the Greater New Orleans area. Through multi-variate statistical analysis of responses derived from an original survey of homeowners in New Orleans, key factors are identified that explain variation in residents’ willingness to accept such areas and their perceptions of ecological benefits associated with a theoretical wetlands restoration design for the Gentilly area. Further, the analysis determines the extent to which direct experience with Hurricane Katrina may influence public support for this and other green infrastructure projects. The results of the data collected show that many people in New ...


Power Series Expansions For Waves In High-Contrast Plasmonic Crystals, Santiago Prado Parentes Fortes 2010 Louisiana State University and Agricultural and Mechanical College

Power Series Expansions For Waves In High-Contrast Plasmonic Crystals, Santiago Prado Parentes Fortes

LSU Doctoral Dissertations

In this thesis, a method is developed for obtaining convergent power series expansions for dispersion relations in two-dimensional periodic media with frequency dependent constitutive relations. The method is based on high-contrast expansions in the parameter _x0011_ = 2_x0019_d=_x0015_, where d is the period of the crystal cell and _x0015_ is the wavelength. The radii of convergence obtained are not too small, on the order of _x0011_ _x0019_ 10􀀀2. That the method applies to frequency dependent media is an important fact, since the majority of the methods available in the literature are restricted to frequency independent constitutive relations. The convergent ...


A Study Of The Interactions Of Lipid Bilayers And Dendrimers Using Small Angle X-Ray Scattering And Freeze Fracture Transmission Electron Microscopy, Derek R. Dorman 2010 Louisiana State University and Agricultural and Mechanical College

A Study Of The Interactions Of Lipid Bilayers And Dendrimers Using Small Angle X-Ray Scattering And Freeze Fracture Transmission Electron Microscopy, Derek R. Dorman

LSU Doctoral Dissertations

Lipids are fundamental to all life forms, a key component of cell walls, and essential to proper respiratory function. They are amphiphilic molecules and readily form bilayers. Dendrimers are designer molecules that can be tailored to provide a variety of endgroup moieties, sizes, and charges. The interaction of liposomes and dendrimers can provide information on how medicine interacts with cells and an array of unique structures can be imagined from their assembly into superstructures. Polypropylenimine tetraamine (DAB-Am) and 1-directional arborol dendrimers have been studied in different molar concentrations with 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) bilayers. One-directional arborols are amphiphilic dendrimers with a ...


Positron Autoradiography For Intravascular Vulnerable Plaque Imaging, Peter Petrek 2010 Louisiana State University and Agricultural and Mechanical College

Positron Autoradiography For Intravascular Vulnerable Plaque Imaging, Peter Petrek

LSU Master's Theses

Purpose: To develop and investigate an intravascular storage phosphor detector for imaging and detection of vulnerable coronary artery plaques. Methods: The concept of the detection of vulnerable plaques (i.e., plaques with inflammation) is based on accumulation of fluorodeoxyglucose (FDG) in inflammation sites. The FDG is labeled with a radioactive isotope 18F (positron source), injected to patient, and accumulated in vulnerable plaques of coronary arteries. The radiation detector is then inserted into coronary artery, records positrons from FDG accumulated in vulnerable plaque, which allows for imaging and detection of the vulnerable plaque. A prototype detector was developed and tested. The ...


Misconceptions On Force And Gravity Among High School Students, Jane Ragasa Pablico 2010 Louisiana State University and Agricultural and Mechanical College

Misconceptions On Force And Gravity Among High School Students, Jane Ragasa Pablico

LSU Master's Theses

The goal of this study is to determine prevalent or dominant misconceptions on force and gravity among high school students. A survey instrument consisting of 12 qualitative questions requiring both answers and written explanations was used to gather students’ ideas and beliefs in situations involving force and gravity. Furthermore, it examined whether the proportion of students having misconceptions per question are correlated with gender and the type of school Physics background. The results show that the respondents have misconceptions that are similar to the misconceptions found in previous research. The number of misconceptions and the proportion of students having misconceptions ...


Choosing Between Remote I/O Versus Staging In Distributed Environments, Ibrahim Hakki Suslu 2010 Louisiana State University and Agricultural and Mechanical College

Choosing Between Remote I/O Versus Staging In Distributed Environments, Ibrahim Hakki Suslu

LSU Doctoral Dissertations

Today, scientifi_x000C_c applications and experiments have become increasingly complex and more demanding in terms of their computational and data requirements. The amount of data generated and used has grown at a very rapid rate. As tens or hundreds of terabytes of data for a single application is very common today; petabytes and even exabytes of data will be very common in a few years. One of the major challenges in distributed computing environments is how to access these large datasets remotely over the network. Data staging and remote I/O are the most widely used data access methods for distributed ...


A Petrophysical Evaluation Of Factors That Control Cap Rock Seal Quality, Andrew Tyler Harrison 2010 Louisiana State University and Agricultural and Mechanical College

A Petrophysical Evaluation Of Factors That Control Cap Rock Seal Quality, Andrew Tyler Harrison

LSU Master's Theses

Textural and mineralogical variations within 33 shale samples were analyzed to provide a model for predication of hydrocarbon top-seal efficiency. Variation in mineral abundances in the subsurface influences petrophysical properties and other characteristics of hydrocarbon sealing sequences and reservoirs. In geophysical well logs, various proxies, such as gamma ray emission and neutron absorption, are used to assess changes in mineral composition. This study directly compares X-ray diffraction measurements of mineral percentages and geophysical responses from Middle Miocene cored intervals in the Santa Cruz Well; Mississippi Canyon block 519, Gulf of Mexico with those derived from well logging. Distinct textural differences ...


Dissolution Of Chitosan In Ionic Liquids For Acylation Chemistry And Formation Of Cellulose-Chitosan Blends, Cristina Stefanescu 2010 Louisiana State University and Agricultural and Mechanical College

Dissolution Of Chitosan In Ionic Liquids For Acylation Chemistry And Formation Of Cellulose-Chitosan Blends, Cristina Stefanescu

LSU Doctoral Dissertations

Dissolution of chitosan in ionic liquids was accomplished. It has been shown that 1-butyl-3-methylimidazolium acetate (BMIMAc) is a better solvent than 1-butyl-3-methylimidazolium chloride (BMIMCl). Dissolution of chitosan in BMIMCl required a prior regeneration of chitosan from 1% acetic acid solution. In the case of BMIMAc, both dried chitosan and regenerated chitosan from acetic acid solution have been dissolved in a relatively short amount of time. While concentrations up to 2 wt% of chitosan in BMIMCl could be obtained, concentrations of 10 wt % of chitosan in BMIMAc were realized. Homogeneous phthalation and benzoylation of chitosan were achieved in these ionic liquids ...


The Effects Of A Freshwater Diversion Of Nekton Species Biomass Distributions, Food Web Pathways, And Community Structure In A Louisiana Estuary, Kim de Mutsert 2010 Louisiana State University and Agricultural and Mechanical College

The Effects Of A Freshwater Diversion Of Nekton Species Biomass Distributions, Food Web Pathways, And Community Structure In A Louisiana Estuary, Kim De Mutsert

LSU Doctoral Dissertations

A current method to restore Louisiana’s estuaries includes reintroducing freshwater and sediments to wetlands that are hydrologically isolated from the Mississippi River due to the construction of levees. In this dissertation, I examined effects of the second largest freshwater diversion in Louisiana, the Caernarvon Freshwater Diversion (CFD), on estuarine nekton in Breton Sound. Before focusing on Breton Sound, I examined the status of nekton communities in the northern Gulf of Mexico (GOM), and Louisiana wetlands in particular, using the mean trophic level index (MTLI). I demonstrated that commercial targeting caused the previously reported low and declining MTLI from the ...


Investigating The Ironwood Tree (Casuarina Equisetifolia) Decline On Guam Using Applied Multinomial Modeling, Karl Anthony Schlub 2010 Louisiana State University and Agricultural and Mechanical College

Investigating The Ironwood Tree (Casuarina Equisetifolia) Decline On Guam Using Applied Multinomial Modeling, Karl Anthony Schlub

LSU Master's Theses

The ironwood tree (Casuarina equisetifolia), a protector of coastlines of the sub-tropical and tropical Western Pacific, is in decline on the island of Guam where aggressive data collection and efforts to mitigate the problem are underway. For each sampled tree the level of decline was measured on an ordinal scale consisting of five categories ranging from healthy to near dead. Several predictors were also measured including tree diameter, fire damage, typhoon damage, presence or absence of termites, presence or absence of basidiocarps, and various geographical or cultural factors. The five decline response levels can be viewed as categories of a ...


Landscape Patterns Of Community Structure, Biomass And Net Primary Productivity Of Mangrove Forests In The Florida Coastal Everglades As A Function Of Resource, Regulators, Hydroperiod, And Hurricane Distrubance, Edward Castaneda 2010 Louisiana State University and Agricultural and Mechanical College

Landscape Patterns Of Community Structure, Biomass And Net Primary Productivity Of Mangrove Forests In The Florida Coastal Everglades As A Function Of Resource, Regulators, Hydroperiod, And Hurricane Distrubance, Edward Castaneda

LSU Doctoral Dissertations

Spatial and temporal patterns of mangrove vegetation in the Florida Coastal Everglades (FCE) reflect a major interplay of resources, regulators and hydroperiod gradients. I investigated landscape patterns of community structure, biomass and NPP of mangroves along two FCE estuaries: Shark River and Taylor River. I also evaluated whether pulsing events such as Hurricane Wilma are significant to soil nutrient inventories and vertical accretion of mangroves in FCE. There was a higher forest structural complexity of mangroves in Shark River relative to Taylor River. The biomass root:shoot ratio was 17 times higher in Taylor River relative to Shark River, indicating ...


Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron 2010 Louisiana State University and Agricultural and Mechanical College

Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron

LSU Doctoral Dissertations

Population growth for mallards (Anas platyrhynchos), and presumably other upland nesting ducks, in the Prairie Pothole Region is most sensitive to nest success, and nest success is most strongly influenced by predation. I evaluated the efficacy of reducing predator populations to improve nest success and increase local breeding populations of upland nesting ducks on township-sized (93.2 km2) management units in eastern North Dakota, USA, during 2005−2008. I also examined potential territorial limitations on local population growth for mallards. Trappers annually removed an average of 245 predators per trapped site. I monitored 7,489 nests on 7 trapped and ...


Ancient Dna Analyses Exclude Humans As The Driving Force Behind Late Pleistocene Musk Ox (Ovibos Moschatus) Population Dynamics, Paula F. Campos, Eske Willerslev, Andrei Sher, Ludovic Orlando, Erik Axelsson, Alexei Tikhonov, Kim Aaris-Sorensen, Alex D. Greenwood, Ralf-Dietrich Kahlke, Pavel Kosintsev 2010 Old Dominion University

Ancient Dna Analyses Exclude Humans As The Driving Force Behind Late Pleistocene Musk Ox (Ovibos Moschatus) Population Dynamics, Paula F. Campos, Eske Willerslev, Andrei Sher, Ludovic Orlando, Erik Axelsson, Alexei Tikhonov, Kim Aaris-Sorensen, Alex D. Greenwood, Ralf-Dietrich Kahlke, Pavel Kosintsev

Biological Sciences Faculty Publications

The causes of the late Pleistocene megafaunal extinctions are poorly understood. Different lines of evidence point to climate change, the arrival of humans, or a combination of these events as the trigger. Although many species went extinct, others, such as caribou and bison, survived to the present. The musk ox has an intermediate story: relatively abundant during the Pleistocene, it is now restricted to Greenland and the Arctic Archipelago. In this study, we use ancient DNA sequences, temporally unbiased summary statistics, and Bayesian analytical techniques to infer musk ox population dynamics throughout the late Pleistocene and Holocene. Our results reveal ...


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