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Diatom Stratigraphy Defining Ice Sheet Grounding Chronology, Ross Sea, Antarctica, Juan Manuel Chow 2010 Louisiana State University and Agricultural and Mechanical College

Diatom Stratigraphy Defining Ice Sheet Grounding Chronology, Ross Sea, Antarctica, Juan Manuel Chow

LSU Doctoral Dissertations

Evidence of Antarctic ice sheet behavior and paleoenvironment is often approached from proxy records because there is a dearth of direct records from Antarctica itself. The studies presented here seek to augment our knowledge of translations of the West Antarctic Ice Sheet’s (WAIS) marine termination based on direct biostratigraphic evidence. Diatom analyses were conducted from two areas of Ross Sea, Antarctica. In the first study, diatoms were used to constrain the age of diamictons from five seismic units in the Eastern Basin and thus expand our knowledge of WAIS behavior during the Southern Hemisphere Last Glacial Maximum (LGM). All ...


Perverse Poisson Sheaves On The Nilpotent Cone, Jared Lee Culbertson 2010 Louisiana State University and Agricultural and Mechanical College

Perverse Poisson Sheaves On The Nilpotent Cone, Jared Lee Culbertson

LSU Doctoral Dissertations

For a reductive complex algebraic group, the associated nilpotent cone is the variety of nilpotent elements in the corresponding Lie algebra. Understanding the nilpotent cone is of central importance in representation theory. For example, the nilpotent cone plays a prominent role in classifying the representations of finite groups of Lie type. More recently, the nilpotent cone has been shown to have a close connection with the affine flag variety and this has been exploited in the Geometric Langlands Program. We make use of the following important fact. The nilpotent cone is invariant under the coadjoint action of G on the ...


The Impact Of Overfitting And Overgeneralization On The Classification Accuracy In Data Mining, Huy Nguyen Anh Pham 2010 Louisiana State University and Agricultural and Mechanical College

The Impact Of Overfitting And Overgeneralization On The Classification Accuracy In Data Mining, Huy Nguyen Anh Pham

LSU Doctoral Dissertations

Current classification approaches usually do not try to achieve a balance between fitting and generalization when they infer models from training data. Such approaches ignore the possibility of different penalty costs for the false-positive, false-negative, and unclassifiable types. Thus, their performances may not be optimal or may even be coincidental. This dissertation analyzes the above issues in depth. It also proposes two new approaches called the Homogeneity-Based Algorithm (HBA) and the Convexity-Based Algorithm (CBA) to address these issues. These new approaches aim at optimally balancing the data fitting and generalization behaviors of models when some traditional classification approaches are used ...


Effective Lesson Planning: Field Trips In The Science Curriculum, Cynthia Rau Rieger 2010 Louisiana State University and Agricultural and Mechanical College

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 ...


Augmented Breast Tumor Classification By Perfusion Analysis, Bruce Yu-Sun Lin 2010 Louisiana State University and Agricultural and Mechanical College

Augmented Breast Tumor Classification By Perfusion Analysis, Bruce Yu-Sun Lin

LSU Doctoral Dissertations

Magnetic resonance and computed tomography imaging aid in the diagnosis and analysis of pathologic conditions. Blood flow, or perfusion, through a region of tissue can be computed from a time series of contrast-enhanced images. Perfusion is an important set of physiological parameters that reflect angiogenesis. In cancer, heightened angiogenesis is a key process in the growth and spread of tumorous masses. An automatic classification technique using recovered perfusion may prove to be a highly accurate diagnostic tool. Such a classification system would supplement existing histopathological tests, and help physicians to choose the most optimal treatment protocol. Perfusion is obtained through ...


Investigating The Effectiveness Of Informal Science Education Through Quantitative And Qualitative Analysis: Ocean Commotion, Catherine Angela Sutera 2010 Louisiana State University and Agricultural and Mechanical College

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 ...


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 ...


Implementation And Analysis Of A Top-K Retrieval System For Strings, Sabrina Chandrasekaran 2010 Louisiana State University and Agricultural and Mechanical College

Implementation And Analysis Of A Top-K Retrieval System For Strings, Sabrina Chandrasekaran

LSU Master's Theses

Given text which is a union of d documents of strings, D = d1, d2,...., dd, the emphasis of this thesis is to provide a practical framework to retrieve the K most relevant documents for a given pattern P, which comes as a query. This cannot be done directly, as going through every occurrence of the query pattern may prove to be expensive if the number of documents that the pattern occurs in is much more than the number of documents (K) that we require. Some advanced query functionality will be required, as compared to listing the documents that the pattern ...


Getting Off The Ground With Ap Calculus, David Frank Woods 2010 Louisiana State University and Agricultural and Mechanical College

Getting Off The Ground With Ap Calculus, David Frank Woods

LSU Master's Theses

“The study of mathematics, like the Nile, begins in minuteness but ends in magnificence.” – Charles Caleb Colton Caught in a downward spiral, American mathematical students continue to be outperformed by their international peers as reported by the TIMSS. This has left educators scrambling to find an instructional strategy that will slow this decline in mathematical literacy. This thesis reports on the framework that a new teacher could use to develop and establish a successful AP Calculus program, while increasing mathematical literacy, equity in the classroom, and student achievement through the integration of educational technology into current instructional trends. This thesis ...


The Influences Of Microbial Diversity On Carbonate Geochemistry Across A Transition From Fresh To Saline Water In The Edwards Aquifer, Texas, Cassie Jo Gray 2010 Louisiana State University and Agricultural and Mechanical College

The Influences Of Microbial Diversity On Carbonate Geochemistry Across A Transition From Fresh To Saline Water In The Edwards Aquifer, Texas, Cassie Jo Gray

LSU Master's Theses

Microbially-mediated karstification through the production of metabolic byproducts has been well-documented in cave environments, but less is known about deep karstic settings. This research aimed to distinguish between microbial and geochemical influences on carbonate dissolution in the Edwards Aquifer, a prolific karst aquifer in central Texas, specifically from a transect of six wells across a transition from fresh to saline water in New Braunfels. For the first time, a portion of the aquifer’s bacterial diversity was examined from molecular 16S rRNA gene sequence analyses, which revealed that Alphaproteobacteria, Gammaproteobacteria, and Betaproteobacteria dominated the aquifer, with rare Bacteroidetes, Nitrospirae, and ...


Pharmaceutical Compounds In Treatment Wetlands: Potential Removal And Effects On Microbial Processes, Jeremy Landon Conkle 2010 Louisiana State University and Agricultural and Mechanical College

Pharmaceutical Compounds In Treatment Wetlands: Potential Removal And Effects On Microbial Processes, Jeremy Landon Conkle

LSU Doctoral Dissertations

active compounds (PhACs) have been detected in the aquatic environment as a result of loading from various sources. In Louisiana, USA, many municipalities treat wastewater using natural systems, such as lagoons and wetlands, rather than using conventional wastewater treatment technologies and may discharge PhACs into the environment. These treatment systems are not designed to remove PhACs from wastewater, nor is it currently a regulatory requirement. Research on the fate of PhACs in the environment is needed to understand impacts on Louisiana’s important coastal system. Wastewater sampling for PhACs at the Mandeville, LA wastewater treatment plant (WWTP) determined that this ...


Rare Earth Elements As An Investigative Tool Into The Source, Age, And Ecology Of Late Miocene To Late Pleistocene Fossils From The Tunica Hills, Louisiana, Lindsey Theresa Yann 2010 Louisiana State University and Agricultural and Mechanical College

Rare Earth Elements As An Investigative Tool Into The Source, Age, And Ecology Of Late Miocene To Late Pleistocene Fossils From The Tunica Hills, Louisiana, Lindsey Theresa Yann

LSU Master's Theses

Rare earth elements were investigated for their potential to determine provenance and depositional environments of vertebrate fossils found as float in creeks of the Tunica Hills region of Louisiana. Elemental analyses are used to test the hypotheses that fossils span multiple time periods, from late Miocene to late Pleistocene, and that elemental profiles can distinguish terrestrial depositional settings from possible estuarine deposits. In addition, the animals present were then used to test the hypothesis that Tunica Hills had late Pleistocene environmental conditions much like the modern Great Lakes region. This study is important because it provides new insight on the ...


Space Weather & Gps Reliant Industries, Jennifer L. Meehan, W. Murtagh 2010 Utah State University

Space Weather & Gps Reliant Industries, Jennifer L. Meehan, W. Murtagh

All Physics Faculty Publications

No abstract provided.


A Global Climatology Of The Mesospheric Sodium Layerfrom Gomos Data During The 2002-2008 Period, D. F. Fussen, F. Vanhellemont, C. T'etart, N. Mateshvili, E. Dekemper, N. Loodts, C. Bingen, E. Kyrola, J. Tamminen, V. Sofieva, A. Hauchecorne, F. Dalaudier, J. L. Bertaux, G. Barrot, L. Blanot, O. Fanton d'Andon, T. Fehr, L. Saavedra, Titus Yuan, C. Y. She 2010 Utah State University

A Global Climatology Of The Mesospheric Sodium Layerfrom Gomos Data During The 2002-2008 Period, D. F. Fussen, F. Vanhellemont, C. T'Etart, N. Mateshvili, E. Dekemper, N. Loodts, C. Bingen, E. Kyrola, J. Tamminen, V. Sofieva, A. Hauchecorne, F. Dalaudier, J. L. Bertaux, G. Barrot, L. Blanot, O. Fanton D'Andon, T. Fehr, L. Saavedra, Titus Yuan, C. Y. She

All Physics Faculty Publications

This paper presents a climatology of the mesospheric sodium layer built from the processing of 7 years of GOMOS data. With respect to preliminary results already published for the year 2003, a more careful analysis was applied to the averaging of occultations inside the climatological bins (10° in latitude-1 month). Also, the slant path absorption lines of the Na doublet around 589 nm shows evidence of partial saturation that was responsible for an underestimation of the Na concentration in our previous results. The sodium climatology has been validated with respect to the Fort Collins lidar measurements and, to a lesser ...


Gis Data: Fairfax County And The City Of Alexandria, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky 2010 Virginia Institute of Marine Science

Gis Data: Fairfax County And The City Of Alexandria, Virginia Shoreline Inventory Report, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky

Data

The data inventory developed for the Shoreline Inventory is based on a three‑tiered shoreline assessment approach. In most cases this assessment characterizes conditions that can be observed from a small boat navigating along the shoreline. The three tiered shoreline assessment approach divides the shorezone into three regions: 1) the immediate riparian zone, evaluated for land use; 2) the bank, evaluated for height, stability, cover and natural protection; and 3) the shoreline, describing the presence of shoreline structures for shore protection and recreational purposes. Hand-held GPS units are used to log features observed in the field.

Three GIS coverages are ...


Millennial-Scale Climate Variability During The Last Glacial Period In The Tropical Andes, Sherilyn C. Fritz, P. A. Baker, E. Ekdahl, G. O. Seltzer, L. R. Stevens 2010 University of Nebraska-Lincoln

Millennial-Scale Climate Variability During The Last Glacial Period In The Tropical Andes, Sherilyn C. Fritz, P. A. Baker, E. Ekdahl, G. O. Seltzer, L. R. Stevens

Papers in the Earth and Atmospheric Sciences

Millennial-scale climate variation during the Last Glacial period is evident in many locations worldwide, but it is unclear if such variation occurred in the interior of tropical South America, and, if so, how the low-latitude variation was related to its high-latitude counterpart. A high-resolution record, derived from the deep drilling of sediments on the floor of Lake Titicaca in the southern tropical Andes, is presented that shows clear evidence of millennial-scale climate variation between ~60 and 20 ka BP. This variation is manifested by alternations of two interbedded sedimentary units. The two units have distinctive sedimentary, geochemical, and paleobiotic properties ...


Climatic And Environmental Controls On The Occurrence And Distributions Of Long Chain Alkenones In Lakes Of The Interior United States, Jaime L. Toney, Yongsong Huang, Sherilyn C. Fritz, Paul A. Baker, Eric Grimm, Paul Nyren 2010 Brown University

Climatic And Environmental Controls On The Occurrence And Distributions Of Long Chain Alkenones In Lakes Of The Interior United States, Jaime L. Toney, Yongsong Huang, Sherilyn C. Fritz, Paul A. Baker, Eric Grimm, Paul Nyren

Papers in the Earth and Atmospheric Sciences

Long chain alkenones (LCA) are temperature-sensitive lipids with great potential for quantitative reconstruction of past continental climate. We conducted the first survey for alkenone biomarkers from 55 different lakes in the Northern Great Plains and Nebraska Sand Hills of the United States. Among those surveyed, we found 13 lakes that contain LCAs in the surface sediments. The highest concentrations of alkenones in sediments are found in cold (mean annual air temperature ~11 °C versus 17 °C in our warmest sites), brackish to mesosaline (salinity = 8.5–9.7 g/L), and alkaline (pH = 8.4–9.0) lakes with high ...


Experimental Studies On The Plasma Bullet Propagation And Its Inhibition, Erdinc Karakas, Mounir Laroussi 2010 Old Dominion University

Experimental Studies On The Plasma Bullet Propagation And Its Inhibition, Erdinc Karakas, Mounir Laroussi

Electrical & Computer Engineering Faculty Publications

Plasma bullets generated by atmospheric pressure low temperature plasma jets have recently been an active research topic due to their unique properties and their enhanced plasma chemistry. In this paper, experimental insights into the plasma bullet lifetime and its velocity are reported. Data obtained from intensified charge-coupled device camera and time-resolved optical emission spectroscopy (OES) elucidated the existence of a weakly ionized channel between the plasma bullet and its source (such as the plasma pencil). Factors responsible for the inhibition of the propagation of the bullet, such as low helium mole fraction, the magnitude of the applied voltage, and the ...


Destruction Of Α -Synuclein Based Amyloid Fibrils By A Low Temperature Plasma Jet, Erdinc Karakas, Agatha Munyanyi, Lesley Greene, Mounir Laroussi 2010 Old Dominion University

Destruction Of Α -Synuclein Based Amyloid Fibrils By A Low Temperature Plasma Jet, Erdinc Karakas, Agatha Munyanyi, Lesley Greene, Mounir Laroussi

Electrical & Computer Engineering Faculty Publications

Amyloid fibrils are ordered beta-sheet aggregates that are associated with a number of neurodegenerative diseases such as Alzheimer and Parkinson. At present, there is no cure for these progressive and debilitating diseases. Here we report initial studies that indicate that low temperature atmospheric pressure plasma can break amyloid fibrils into smaller units in vitro. The plasma was generated by the plasma pencil, a device capable of emitting a long, low temperature plasma plume/jet. This avenue of research may facilitate the development of a plasma-based medical treatment.


Design Of Organic Tandem Solar Cells Using Pcpdtbt: Pc61 Bm And P3ht: Pc71bm, Gon Namkoong, Patrick Boland, Keejoo Lee, James Dean 2010 Old Dominion University

Design Of Organic Tandem Solar Cells Using Pcpdtbt: Pc61 Bm And P3ht: Pc71bm, Gon Namkoong, Patrick Boland, Keejoo Lee, James Dean

Electrical & Computer Engineering Faculty Publications

We conducted optical and electrical simulations with the goal of determining the optimal design for conjugated polymer-fullerene tandem solar cells using poly[2,6-(4,4-bis-(2-ethylhexyl)- 4H-cyclopenta[2,1- b;3,4- b′] dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT): [6,6]-phenyl C61 butyric acid methyl ester (PC61 BM) as a bottom cell and poly(3-hexylthiophene) (P3HT): [6,6]-phenyl C71 butyric acid methyl ester (PC71BM) as a top cell. The effects of photon density, absorption, balanced and unbalanced charge carrier transport, and bimolecular recombination in the two subcells were incorporated into the ...


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