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Full-Text Articles in Physical Sciences and Mathematics

Rate Of Change With Applications In Physics Problems, Maria Ludu Jan 2009

Rate Of Change With Applications In Physics Problems, Maria Ludu

LSU Master's Theses

In this thesis we approach the concept of Rate of Change as a mathematical model, and we apply it to a few physics problems. Its main goal is to help students to bridge concepts form mathematical models and the real life applications. We begin with a review of measurements, proportionality and similarity based on Euclidean geometry; then, we review linear and affine functions, and we introduce a mathematical model for the average and instantaneous rate of change. This mathematical model is applied to problems from physics following the four representations of functions: verbal, algebraic, tabular and graphical. By doing so, …


Project-Based High School Geometry, Danica Le'trice Robinson Jan 2009

Project-Based High School Geometry, Danica Le'trice Robinson

LSU Master's Theses

Project-based learning (PBL) is an instructional strategy that allows students the autonomy to learn, explore and investigate throughout the learning process by means of projects. Many educators have seen the need for such a strategy in the classroom as a remedy for motivating students, showing relevance of student’s education to everyday life, preparing students for college and the work force, and the dire need for students to develop critical thinking skills to encourage future success. In my thesis I will define project-based learning, discuss its characteristics, compare PBL to traditional teaching methods and reflect on my experiences with project-based learning …


Ratio And Proportion: Mapping The Conceptual Field, Christina Vincent Jan 2009

Ratio And Proportion: Mapping The Conceptual Field, Christina Vincent

LSU Master's Theses

Ratio and proportion are central to the middle school mathematics curriculum, but the full scope and extent of this topic is not described in detail in most state curriculum standards. In this thesis, numerous textbooks from the past one hundred years are sampled, along with several state‟s standards and the Louisiana state comprehensive curriculum. These sources are used to develop a more defined map of ratio and proportion as a conceptual field and a structured collection of problems. Proportional reasoning involves three phases: 1) the comparison of two magnitudes, expressed as ratio or rate, 2) the comparison of two ratios, …


Your Land Is My Land: Exploring Land Policy In Tangerang, Indonesia Using Kingdon's Multiple Streams Model, Milla Budiarto Jan 2009

Your Land Is My Land: Exploring Land Policy In Tangerang, Indonesia Using Kingdon's Multiple Streams Model, Milla Budiarto

LSU Master's Theses

Indonesia is the world’s largest archipelagic country comprised of over 17, 000 islands with more than 300 ethnic groups and more than 250 different ethnic languages spoken. Due to its land mass size and multifaceted culture, land policy in this country has been ineffective and inadequate in addressing some of the land affairs. One of the indicators of effective land policy is land tenure security, where land dispute incidence is a function of it. Given that the government has very minimal guarantee for land tenure security in this nation, land disputes are inevitable and very common. By the end of …


Creating An Empirically Derived Community Resilience Index Of The Gulf Of Mexico Region, Ariele Nicole Baker Jan 2009

Creating An Empirically Derived Community Resilience Index Of The Gulf Of Mexico Region, Ariele Nicole Baker

LSU Master's Theses

As coastal areas increase in populations there is an increasing need to determine what community characteristics are most resilient to coastal disasters. This research proposes two methods to quantify community resilience. The factor analysis method results in a weighted additive index model of six variables to derive community resilience. The index places every community in the Gulf of Mexico on a scale from 0-1. The most resilient counties in the Gulf of Mexico region were found to be Hillsborough, FL, Pinellas, FL, Sarasota, FL, Hernando, FL, Okaloosa, FL, Kenedy, TX, and Jefferson, LA with a resilience score of 1. The …


Translocation Success Of Adult Red-Cockaded Woodpeckers, Erin Herbez Jan 2009

Translocation Success Of Adult Red-Cockaded Woodpeckers, Erin Herbez

LSU Master's Theses

The red-cockaded woodpecker (Picoides borealis; hereafter RCW) is a cooperative breeder endemic to open old-growth pine savannah ecosystems in the southeastern United States (Jackson 1994). The RCW was listed as federally endangered in 1973, after a population decline due to habitat loss. Habitat fragmentation produces isolated populations of RCWs, which in turn ultimately limits the success of the species. RCW biologists and managers counteract effects of fragmentation by aggregating recruitment clusters and translocation. Although several studies examined subadult RCW translocation, detailed studies examining adult translocation have been limited. My study was conducted on a 3500 ha area owned by Plum …


Greedy Methods For Approximate Graph Matching With Applications For Social Network Analysis, Partha Basuchowdhuri Jan 2009

Greedy Methods For Approximate Graph Matching With Applications For Social Network Analysis, Partha Basuchowdhuri

LSU Master's Theses

In this thesis, we study greedy algorithms for approximate sub-graph matching with attributed graphs. Such algorithms find one or multiple copies of a sub-graph pattern from a bigger data graph through approximate matching. One intended application of sub-graph matching method is in Social Network Analysis for detecting potential terrorist groups from known terrorist activity patterns. We propose a new method for approximate sub-graph matching which utilizes degree information to reduce the search space within the incremental greedy search framework. In addition, we have introduced the notion of a “seed” in incremental greedy method that aims to find a good initial …


Using Demographic Models To Manage Chinese Privet (Ligustrum Sinense Lour.), Metha Martine Klock Jan 2009

Using Demographic Models To Manage Chinese Privet (Ligustrum Sinense Lour.), Metha Martine Klock

LSU Master's Theses

Colonization of natural areas by Chinese privet (Ligustrum sinense Lour.) threatens biodiversity and preservation of native habitat in the southeastern United States. High rates of seed production and dispersal, coupled with clonal growth, result in a competitive advantage when introduced to novel areas. Land managers have attempted to control L. sinense through prolonged flooding, prescribed fire, and herbicide application with little success. I determined presence of L. sinense invasion in four sites in Louisiana and assessed key reproductive, growth, and survivorship characteristics defining its life course. I used vegetation surveys, germination trials, dendrochronology, and demographic models to elucidate stages in …


The Use Of The Online Tutorial And Assessment System, Mathxl, In Teaching Of Algebra I, Darlene Noble Ford Jan 2009

The Use Of The Online Tutorial And Assessment System, Mathxl, In Teaching Of Algebra I, Darlene Noble Ford

LSU Master's Theses

The integration of web based learning tools into the teaching of mathematics holds much promise for engaging middle and high school students. The purpose of this thesis is to report about my experiences regarding the effectiveness of using an online homework, tutorial and assessment system as part of two of the six Algebra I math classes I taught in the 2008-2009 school year at Sherwood Middle Academic Magnet School in East Baton Rouge Parish. Comparing the two sets of classes I found that such online systems offer many potential advantages to educators, such as the ability to provide instantaneous feedback, …


Do Laminated Sediment-Gravity-Flow Deposits On The Antarctic Peninsula Continental Shelf Record Ice Sheet Grounding Events?, Vincent Clyde Adams Jan 2009

Do Laminated Sediment-Gravity-Flow Deposits On The Antarctic Peninsula Continental Shelf Record Ice Sheet Grounding Events?, Vincent Clyde Adams

LSU Master's Theses

Barker and Camerlenghi (2002) proposed that drifts on the continental rise of the Antarctic Peninsula may record a high-resolution record of ice-sheet expansions on the adjacent continental shelf. In their view, laminated sediments were deposited during glacial periods, whereas during interglacial periods, sediment supply to drifts was negligible. As a consequence of low sediment supply, the tops of laminated sequences were bioturbated. Therefore, a bioturbated-laiminated couplet should represent a complete glacial cycle. Bioturbated and laminated (B-L) sediment couplets were compiled from cores at two drift sites obtained from Ocean Drilling Program (ODP) Leg 178 Sites 1095, 1096, and 1101. If …


Fine- To Basin-Scale Distributions Of Calanus Finmarchicus And Its Predators In Three Deep Basins Of The Gulf Of Maine During December 1998 And 1999 From Video Plankton Recorder (Vpr) Data, Christian Briseño-Avena Jan 2009

Fine- To Basin-Scale Distributions Of Calanus Finmarchicus And Its Predators In Three Deep Basins Of The Gulf Of Maine During December 1998 And 1999 From Video Plankton Recorder (Vpr) Data, Christian Briseño-Avena

LSU Master's Theses

The calanoid copepod Calanus finmarchicus is broadly distributed in the North Atlantic, where it dominates the spring zooplankton biomass of shelf ecosystems. Calanus finmarchicus diapauses in the deep basins of the Gulf of Maine (GOM) during late-summer through early-winter. During diapause, predators that co-occur in regions of high copepod abundance may reduce survivorship through predation. Consequently it is important to measure the distribution patterns of C. finmarchicus and its predators. Two cruises were carried out during December of 1998 and 1999 in the GOM. Video Plankton Recorder (VPR) data collected in Wilkinson, Jordan and Georges Basins were used to describe …


Characterization And Transitions Of Asphalt Cement Composite Materials, Brent Harper Sellers Jan 2009

Characterization And Transitions Of Asphalt Cement Composite Materials, Brent Harper Sellers

LSU Master's Theses

Blends of a PG 64-22 asphalt with a range of load levels (0.2 — 20 wt %) of Sasobit® wax and a single loading of 2 wt % Elvaloy AM® were prepared and characterized. Sasobit® wax is a high molecular weight paraffinic wax produced commercially through the Fischer-Tropsch process. Elvaloy AM® is a reactive elastic terpolymer, comprised of ethylene, butyl acrylate and glycidyl methacrylate monomeric units. The blends were analyzed by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), x-ray diffraction, epifluorescence microscopy, scanning laser confocal microscopy, and dynamic shear rheology. Sasobit (1 wt %) composite material showed little difference …


Applying The Isotope Pairing Technique To Evaluate How Water Temperature And Habitat Type Influence Denitrification Estimates In Breton Sound, Louisiana, Peter L. Lenaker Jan 2009

Applying The Isotope Pairing Technique To Evaluate How Water Temperature And Habitat Type Influence Denitrification Estimates In Breton Sound, Louisiana, Peter L. Lenaker

LSU Master's Theses

The upper Breton Sound estuary was hydrologically reconnected to the Mississippi River via the Caernarvon freshwater diversion structure in 1991. The Caernarvon structure can provide controlled freshwater pulses to the upper Breton Sound estuarine ecosystem, replicating historic freshwater pulsed events, although the original authorization was to control salinity isohalines at specific locations in the estuary. However, unlike historic freshwater pulsed events prior to the construction of levees, the current freshwater pulse contains an unprecedented amount of inorganic nitrogen, predominately as nitrate (annual average 71.4 µM NO3-). Denitrification is a microbial process, which can potentially remove excess nitrate entering coastal Louisiana …


Comparison Of Helical Tomotherapy And Mixed Beam Treatment Plans For Superficial Head And Neck Cancers, Olivier C. Blasi Jan 2009

Comparison Of Helical Tomotherapy And Mixed Beam Treatment Plans For Superficial Head And Neck Cancers, Olivier C. Blasi

LSU Master's Theses

Purpose: To compare helical tomotherapy (HT) with mixed beam therapy (electron and IMRT) plans for superficial parotid gland and nasal cavity tumors. Methods: Mixed beam and HT dose plans were developed for five patients with superficial tumors (planning target volume or PTV < 5.5 cm depth), three with parotid gland tumors and two with nasal cavity tumors. Seven mixed beam plans included a 5 or 7-field photon IMRT plan optimized on top of a single en-face 16 or 20 MeV electron beam dose distribution. The ratio of photon to electron beam weights (at depth R100) were 1:0 (IMRT only), 2:1, 1:1, 1:2, 1:3, 1:4, and 0:1 (electrons only). Planning objectives for HT plans were set as closely as possible to those in the mixed beam plans, and were determined using our clinical planning protocol for head and neck cancers. The resulting dose distribution from each plan was evaluated using dose-volume quantities, tumor control probability (TCP), normal tissue complication probability (NTCP), and a clinical evaluation by a radiation oncologist. Results: In general, the HT plans showed better target coverage and dose homogeneity index (DHI) than the mixed beam plans. For the parotid patients, the DHI improved an average of 0.056 and 0.035 for the nasal cavity patients compared to the mixed beam plan. TCP was comparable in all patients. NTCP for the mixed beam plan was generally lower or comparable to HT with the largest improvements seen in the contralateral parotid, eye, and lens. Also, the mixed beam plans yielded more favorable PTV and normal tissue results for a single shallow uniform PTV using a heavier weighted electron to IMRT ratio (1:3 or 1:4 ratio of electron to IMRT). Conclusions: The study showed that while HT plans had better target coverage and dose homogeneity, the mixed beam plans (electron and IMRT) had comparable tumor control probability and have the potential for improving NTCP for distal normal tissue for superficial uniform PTVs.


Source(S) Of Salinity In The Mississippi River Alluvial Aquifer, Iberville Parish, Louisiana, Stephanie Erin Welch Jan 2009

Source(S) Of Salinity In The Mississippi River Alluvial Aquifer, Iberville Parish, Louisiana, Stephanie Erin Welch

LSU Master's Theses

The Mississippi River Alluvial Aquifer extends from Southern Illinois to the mouth of the Mississippi and is comprised of fluvial sands and gravels of Late Pleistocene age. Several areas of the aquifer in Arkansas, Mississippi, and Louisiana are affected by elevated levels of salinity. One such area occurs in Iberville Parish, LA, where the aquifer is 150-240 m in thickness and is capped by 23-38 m of clay. Recharge of the aquifer from the Mississippi River on the east is fresh, but salinity is high in the western portions of the aquifer and chloride levels are as high as 1,000 …


Provenance Studies Of Volcanic Clasts From The Santa Fe Group, San Luis Basin, Colorado: A Guide To Tectonic Evolution, Corine Kay Armstrong Jan 2009

Provenance Studies Of Volcanic Clasts From The Santa Fe Group, San Luis Basin, Colorado: A Guide To Tectonic Evolution, Corine Kay Armstrong

LSU Master's Theses

Volcanic clasts at the base of the Tertiary Santa Fe Group of the San Luis Basin (SLB), a major extensional feature of the northern Rio Grande Rift, provide evidence for the direction of sediment transport and timing of regional tectonic events. A combination of clast whole rock geochemistry (major and trace element), mineral chemistry (amphibole, biotite, pyroxene and feldspar) and geochronology (40Ar/39Ar of amphibole and biotite and U-Pb of zircons) is used to constrain the possible source scenarios. Several potential sources with requisite geochemical and geochronological information exist for the Santa Fe Group volcanic clasts including rocks from Spanish Peaks …


Neurotoxin In A Louisiana Estuary: Quantitative Analysis Of Domoic Acid In Gulf Menhaden (Brevoortia Patronus) And Qualitative Modeling Of Links In A Shark Nursery, Ross Del Rio Jan 2009

Neurotoxin In A Louisiana Estuary: Quantitative Analysis Of Domoic Acid In Gulf Menhaden (Brevoortia Patronus) And Qualitative Modeling Of Links In A Shark Nursery, Ross Del Rio

LSU Master's Theses

Harmful algal blooms are an increasing problem for coastal waters world-wide. The diatom genus, Pseudo-nitzschia, is of particular concern in Louisiana, due to the potential for several species to produce the neurotoxin domoic acid (DA). While trophic transfer of DA to consumers has repeatedly occurred along the California coast, little is known about trophic transfer of recently detected DA in the Gulf of Mexico. In this study, the presence of DA in gulf menhaden (Brevoortia patronus) and the potential for trophic transfer to higher order consumers was investigated. In addition, the effects of this transfer and other algal toxins that …


A Geochemical Paleoecological Analysis Of Miocene Mammalian Mega Fauna Of Fort Polk, Louisiana, Travis Lamar Atwood Jan 2009

A Geochemical Paleoecological Analysis Of Miocene Mammalian Mega Fauna Of Fort Polk, Louisiana, Travis Lamar Atwood

LSU Master's Theses

Through a combination of vertebrate paleontology and geochemistry much can be discovered about the environments about the past. Fort Polk’s vertebrate fossil sites are important because they reflect a time when the Antarctic ice cap was just beginning to form during the middle Miocene cooling period just after the middle Miocene Climatic Optimum (~15Ma). This study tested the hypothesis that Miocene seasonality will be preserved in the isotopic geochemistry of terrestrial vertebrate remains at central North American Gulf Coastal sites. Geochemistry was used to understand fossil diagenesis, faunal communities and paleoenvironments. Fort Polk, LA sites range in age from 13.5 …


M. Effects Of Land Use And Habitat On Stream Fish Assemblages In Tributaries Of The Lower Bogue Chitto Watershed, Washington Parish, Louisiana, Brian Michael Ward Jan 2009

M. Effects Of Land Use And Habitat On Stream Fish Assemblages In Tributaries Of The Lower Bogue Chitto Watershed, Washington Parish, Louisiana, Brian Michael Ward

LSU Master's Theses

My research focused on how fish communities are responding to watershed land use and instream habitat in tributaries of the Lower Bogue Chitto River. To address this question I electrofished and seined 10 sites in four tributaries of the Bogue Chitto River a total of 4 times each over the course of 15 months in 2007 and 2008. I characterized habitat by measuring water flow, water depth, substrate size, woody debris, temperature, and dissolved oxygen, and quantified heterotrophic plate counts, nutrients, and chlorophyll a concentrations at the end of the sampling period each year. Watershed land cover was measured with …


Life History Characteristics Of Alligator Gar, Atractosteus Spatual, In The Bayou Dularge Area Of Southcentral Louisiana, Kayla Cheree Dibenedetto Jan 2009

Life History Characteristics Of Alligator Gar, Atractosteus Spatual, In The Bayou Dularge Area Of Southcentral Louisiana, Kayla Cheree Dibenedetto

LSU Master's Theses

The alligator gar Atractosteus spatula is a large, long-lived, physostomous fish that inhabits aquatic habitats throughout the central U.S., ranging from Oklahoma southward to the Gulf of Mexico. Unfortunately, the alligator gar has declined significantly in abundance throughout much of its historic range and is now considered vulnerable to localized extirpation. The goal of this study was to provide basic data on the ecology and life history of a commercially-exploited alligator gar population in south Louisiana. This study also focused on age determination and alternate aging techniques such as sectioned otoliths and sectioned scales. From 10 April 2007 through 21 …


Integrated Technology: Does It Affect Learner Outcomes?, Adam Ross Barrett Jan 2009

Integrated Technology: Does It Affect Learner Outcomes?, Adam Ross Barrett

LSU Master's Theses

Because technology has become prevalent in classrooms, this study was undertaken to test whether the use of integrated technology, specifically computers and online activities, affects learner outcomes in a classroom setting. The outcomes from classes taught using integrated technology were compared to classes taught with traditional teaching strategies. Students in a 7th grade life-science class were given pre-tests and post-tests to determine their learning gains on the topics of genetics and photosynthesis. Each class was assigned different activities based on the subject. Each unit was covered in four 90 minute periods. When one set of classes was using integrated technology …


Distribution And Habitat Associations Of Breeding Secretive Marsh Birds In The Mississippi Alluvial Valley Of Northeast Louisiana, Jonathon Joseph Valente Jan 2009

Distribution And Habitat Associations Of Breeding Secretive Marsh Birds In The Mississippi Alluvial Valley Of Northeast Louisiana, Jonathon Joseph Valente

LSU Master's Theses

Populations of many North American secretive marsh birds (SMBs) have declined over the past 30 years, primarily as a function of wetland loss. Ranges for many of these species encompass Louisiana and researchers have investigated various characteristics associated with breeding populations in coastal wetlands, yet similar knowledge is lacking for other parts of the state. I investigated distributions and habitat characteristics associated with breeding SMBs in wetlands and rice fields of the lower Mississippi Alluvial Valley (MAV) of northeast Louisiana. In the 2007 and 2008 breeding seasons we conducted repeated bird surveys in 118 wetlands and 76 rice fields. Common …


Modeling Gag Grouper (Mycteroperca Microlepis) In The Gulf Of Mexico: Exploring The Impact Of Marine Reserves On The Population Dynamics Of A Protogynous Grouper, Robert D. Ellis Jan 2009

Modeling Gag Grouper (Mycteroperca Microlepis) In The Gulf Of Mexico: Exploring The Impact Of Marine Reserves On The Population Dynamics Of A Protogynous Grouper, Robert D. Ellis

LSU Master's Theses

The gag grouper (Mycteroperca microlepis) population in the Gulf of Mexico supports both a commercial and recreational fishery but has experienced a decrease in the male to female sex ratio over the past thirty years. Protogynous fish populations naturally have a smaller male to female ratio than gonochoristic fish populations; however the decline in the gag population is such that sperm limitation may be occurring. In an effort to correct the decline in sex ratio, fishery managers have recently implemented two marine reserves designed specifically to protect gag spawning aggregations. Results from two population models (an age-structured model and an …


Hydrodynamic Response To Cold Fronts Along The Louisiana Coast, Zhixuan Feng Jan 2009

Hydrodynamic Response To Cold Fronts Along The Louisiana Coast, Zhixuan Feng

LSU Master's Theses

Cold fronts play important roles in flushing water out of the Louisiana estuaries. This study is aimed at examining the impact of cold front passages on the hydrodynamics in autumn-winter-spring of 2006-2007, and tries to determine the geographic difference, correlation and relative importance of winds, tides, and river discharge on water level variability and flow field. The amplitude spectra of water level reveal that diurnal tides dominate most stations. Areas west of 91°W have relatively high semidiurnal tides. The subtidal fluctuations are mainly wind-driven. Only the station in the Atchafalaya River shows obvious response to the spring flood of the …


Capillary Electrophoretic Separations Of Enzyme Inhibitors With Activity-Based Detection, Xiaoyan Yan Jan 2009

Capillary Electrophoretic Separations Of Enzyme Inhibitors With Activity-Based Detection, Xiaoyan Yan

LSU Master's Theses

A technique for separating and detecting enzyme inhibitors was developed using capillary electrophoresis with an enzyme microreactor. The on-column enzyme microreactor was constructed using one or two NdFeB magnets in two configurations to immobilize alkaline phosphatase-coated superparamagnetic beads with diameters of 2.8 µm inside a capillary before the detection window. Enzyme inhibition assays were performed by injecting a plug of inhibitor into a capillary filled with an alkaline phosphatase substrate, AttoPhos. Product generated in the enzyme microreactor was detected by laser-induced fluorescence. Inhibitor zones electrophoresed through the capillary, passed through the enzyme microreactor, and were observed as negative peaks due …


Substituted Bis(Beta-Diketones) For Molecular Squares, Jace Sandifer Jan 2009

Substituted Bis(Beta-Diketones) For Molecular Squares, Jace Sandifer

LSU Master's Theses

Our group has been synthesizing porous supramolecular metal-organic molecules using multidentate β-diketones as ligands. For example, m-phenylenebis(acetylacetone) (m-pbaH2, 1) and m-phenylenebis(dipropionylmethane) (m-pbprH2, 2) were readily converted to the molecular squares Cu4(m-pba)4 (6) and Cu4(m-pbpr)4 (7), which bind guests such as 4,4’-bpy and C60.1 However, 6 and 7 are only soluble in a few solvents, limiting their use in practical applications. It is therefore necessary to derivatize the ligand with different functional groups in order to improve solubility and adjust host-guest properties. Simple alkoxy derivatives should prove useful in testing this idea as they would be relatively chemically inert and should …


Seasonal Variability In Absorption And Fluorescence Properties Of Chromophoric Dissolved Organic Matter In The Barataria Basin, Louisiana, Usa, Shatrughan Singh Jan 2009

Seasonal Variability In Absorption And Fluorescence Properties Of Chromophoric Dissolved Organic Matter In The Barataria Basin, Louisiana, Usa, Shatrughan Singh

LSU Master's Theses

Absorption and fluorescence measurements of chromophoric dissolved organic matter (CDOM) were examined along a transect containing 36 sampling stations in the Barataria Basin during high and low conditions to observe seasonal variation in these optical properties. The objectives of this study were (i) to observe CDOM variability in Barataria Basin in variable flow (high and low) conditions, and to characterize the CDOM, (ii) to identify the constituents of CDOM and to model CDOM compositional variability in the Barataria Basin using parallel factor analysis (PARAFAC). CDOM–salinity relationships were non-conservative in lower and upper part of the transect; however a conservative inverse …


Environmental Influences On The Mobility And Speciation Of Arsenic In The Geothermal Waters Of El Tatio Geyser Field, Chile, Lindsey R. Johnson Jan 2009

Environmental Influences On The Mobility And Speciation Of Arsenic In The Geothermal Waters Of El Tatio Geyser Field, Chile, Lindsey R. Johnson

LSU Master's Theses

El Tatio geyser field, northern Chile, impacts regional water quality, policy, and agricultural commerce due to the geothermal waters containing high concentrations of naturally-occurring arsenic (As). In the circumneutral pH, non-sulfidic thermal waters at El Tatio, dissolved arsenite [As(III)] dominates geyser discharge water upstream, but dissolved arsenate [As(V)] dominates downstream. Microbial mats and sediments were analyzed for changes in As speciation using X-ray spectroscopy methods, such as XANES and EXAFS at both the As and Fe K-edges, combined with ATR-FTIR spectroscopy and molecular genetics, to understand As cycling. The sediments and microbial mats were dominated by As(V) speciated as both …


Moderating Effects Of Knowledge, Gender, And Education On The Relationship Between Environmental Value Orientation And Support For Louisiana Coastal Restoration, Meya Voorhies Holloway Jan 2009

Moderating Effects Of Knowledge, Gender, And Education On The Relationship Between Environmental Value Orientation And Support For Louisiana Coastal Restoration, Meya Voorhies Holloway

LSU Master's Theses

Coastal Louisiana marshes are eroding at a rate equivalent to one football field every thirty minutes. It is vital to understand the perceptions of the American public regarding this issue. I conducted a self-administered mail survey during the spring of 2006. The survey was sent to 4,500 residents living in the Mississippi River Valley. The survey was used to identify respondents environmental value orientations, assess respondents attitudes with regards to support for restoration funding for Louisiana’s coastal wetlands, and to determine if outside moderating effects occurred to make respondents with specific value orientations (Anthropocentric or Biocentric) more likely to support …


Resiliency Of New Orleans Following Hurricane Katrina: A Study Of Communities Three Years After The Storm, Lauren Marie Defrank Jan 2009

Resiliency Of New Orleans Following Hurricane Katrina: A Study Of Communities Three Years After The Storm, Lauren Marie Defrank

LSU Master's Theses

In 2005, Hurricane Katrina and subsequent levee failures produced widespread flooding in New Orleans, Louisiana and forced the evacuation of most of the local population. This event allowed for the study of the community’s resilience, or the ability of a system to absorb changes or perturbations and still function. Statistical analysis and case studies were used to study resilience and answer the following questions. Can natural community recovery models be used when evaluating the population recovery of a human community following a disturbance? Given that there are variations in population recovery patterns, what factors account for this difference in recovery? …