Digital Commons Network^™

Development Of Polymer-Based In-Plane Nanopore For Dna Sequencing, Zheng Jia

LSU Doctoral Dissertations

Mechanically robust solid-state nanopores have the potential to be the next generation DNA sensing platforms. However, mass production and limited base-calling accuracy are the hurdles for solid-state nanopore based DNA sensing. In order to solve these problems, a polymer dual-nanopore device fabricated via high throughput nanoimprint lithography (NIL) was proposed to sequence DNA by time-of-flight (ToF) measurement. As a proof of concept, this study presents mononucleotides discrimination via ToF measurement using polymer in-plane dual-nanopore device.

First, fabrication of polymer in-plane nanopore with controllable dimensions was studied in consideration of experimental conditions and materials selection. Then, surface charge density effect on …

Citizen Science In 4-H: Youth Volunteer Motivations, Participation, Retention And Scientific Literacy, Veronica Del Bianco

LSU Doctoral Dissertations

The primary purpose of this study was to examine the influence of volunteer motivation, participation, and citizen science project type on the retention and scientific literacy of 4-H youth volunteers ages 8-19 years participating in science projects. The conceptual model of participation in organized activities (OA) proposed by Bohnert, Fredericks and Randall (2010) was used as a framework for the variables included in the study categorizing them as predictors of participation, participation, program characteristics, or outcomes. A systematic review of volunteer motivations, retention, and scientific literacy in citizen science projects exposed that the literature contains silos of information published in …

Analysis Of The Soil Health Of Pastures Over-Seeded With Winter Annuals, Kathleen M. Bridges

LSU Doctoral Dissertations

Utilizing winter annuals in livestock pastures reduces feed costs of hay, and provides additional vegetative cover that is beneficial to the soil. However, how this practice affects the soil microbial communities has not been well studied. Two sites were included in this study. Both were commercial cattle grazing operations that over-seeded a mixture of grasses, legumes, and brassicas into pastures dominated by bahiagrass (Paspalum notatum). Soil health was assessed using a suite of physical, chemical, and biological properties. Soil physical assessments included bulk density and aggregate stability. Soil chemical assessments included macronutrients, pH, soil organic matter (SOM), total …

Natural Resources-Based Conflicts In Coastal Louisiana: A Multi-Faceted Social And Ecological Setting, Audrey Grismore

LSU Doctoral Dissertations

The Louisiana coastal zone supports numerous natural resource-based economies and due to overlapping demands on the same territory, conflicts among users and resource managers have emerged. When the state recognized serious depletion of oysters in the late nineteenth century, it intervened with a set of conservation polices to try to establish sustained yields that produced one set of conflicts. When the oil industry began operating in the coastal estuaries and wetlands in the 1930s, it produced additional conflicts with fishing folk. The zone of conflict gave rise to cyclic adaptations as each group struggled to sustain its environmentally based economic …

Effect Of Heat Stress On Bovine Follicular Development And Epigenetic Changes, Fabian Andres Diaz

LSU Doctoral Dissertations

Climate is one of the most important limiting factors in animal production. Cattle under the effect of heat stress have reduced fertility. Negative effects during gamete maturation and embryo development have been observed at the morphological, biochemical, transcriptional and developmental levels. Epigenetic mechanisms play a fundamental role in the regulation of gamete and embryo development. Several genes activated during gamete maturation and early embryo development are controlled by epigenetic mechanisms. There are no studies evaluating the effect of heat-stress on the epigenetic profile of bovine oocytes and embryos. Similarly, there is no information on the effect of heat stress on …

Tip Enhanced Laser Assisted Sample Transfer For Biomolecule Mass Spectrometry, Kermit King Murray, Suman Ghorai, Chinthaka A. Seneviratne

College of Science Patents

Disclosed are various embodiments for transferring molecules from a surface for mass spectrometry and other sample analysis methods, and the like. A laser is focused onto a tip of an atomic force microscope to remove and capture a quantity of molecules from the surface, so they can be transferred to a mass spectrometer or another instrument for analysis.

Induced Resistance In Rice, Oryza Sativa, To Herbivores In The Southern United States, Emily Clare Kraus

LSU Doctoral Dissertations

The effects of herbivory and chemical applications as potential inducers of resistance to herbivores in rice, Oryza sativa L., were explored through a series of field, greenhouse, and laboratory experiments. Studies were conducted to investigate the preference and performance of several herbivore pests of rice with a focus on, Lissorhoptrus oryzophilus Kuschel, the rice water weevil (RWW), under conditions where rice plants had been stressed by previous herbivory or chemical applications. The effects of defoliation by Spodoptera frugiperda (J.E. Smith), the fall armyworm, on resistance and tolerance of rice to RWW under field conditions were examined. Herbivory by fall …

Genome Wide Association Studies For Identification Of Markers Linked To Sucrose Traits In Sugarcane, Nathanael Darrell Fickett

LSU Doctoral Dissertations

Sugarcane, being a complex aneu-polyploid, poses unique challenges to fine mapping of quantitative trait loci (QTL) controlling agronomic traits of interest. Genome-wide association studies (GWAS) could be a better alternative to identify molecular markers associated with specific traits due to high linkage disequilibrium in sugarcane. In the first study, marker-trait associations (MTAs) were evaluated for three sucrose traits, Brix, total recoverable sugar (TRS), and percent sucrose on 48 elite and historic Louisiana breeding clones using 1,062 alleles. These sucrose traits were highly correlated (P-value < 0.0001) at >0.96. TASSEL 5.1 and JMP Genomics 8.0 were compared with eight models run in each program. …

Dispersing And Depositing Mose2 Onto Metal, Insulating, And Semiconducting Substrates Via Voltage-Controlled Deposition Technique, Kalyan Chakravarthy Byrisetty

LSU Master's Theses

In today’s world, consumer electronics are getting smaller than ever. These reductions in size are preceded by advancements in electronic materials engineering and related fields. The need for materials that have various properties and are suitable for applications also necessitated research on different materials. Growing research in the applications of graphene led the way to the discovery of materials that have similar properties to graphene. In this way, the transition metal di-chalcogenides (TMDCs) came into use for electrical engineering. Techniques are required to put TMDCs into application, however here we are going to explain the vital focus of our research …

Synergistic Effects Of Temperature And Salinity On The Gene Expression And Physiology Of Crassostrea Virginica, Hollis Jones

LSU Master's Theses

Crassostrea virginica, the eastern oyster, forms reefs that provide critical services and benefits to the resiliency of the surrounding ecosystem. Changes in environmental conditions, including salinity and temperature, can dramatically alter the services oysters provide by affecting their population dynamics. Climate warming may further exacerbate the effects of salinity changes as precipitation events increase in frequency, intensity, and duration. Temperature and salinity independently and synergistically influence gene expression and physiology in marine organisms. We used comparative transcriptomics, physiology, and a field assessment experiment to investigate whether Louisianan oyster are changing their phenotypes to cope with increased temperature and salinity …

Tidal-, Wind-, And Buoyancy-Driven Dynamics In The Barataria Estuary And Its Impact On Estuarine-Shelf Exchange Processes, Linlin Cui

LSU Doctoral Dissertations

A three-dimensional, high-resolution, Finite-Volume Coastal Ocean Model (FVCOM) was used to study the dynamics of Barataria Estuary located in the Southeastern Louisiana. Three numerical experiments with different discharge scenarios, including the actual discharge (average ~ 160 m³ s^-1) from the Davis Pond Diversion (DPD) over three months from April to June 2010, no discharge (NO), and the proposed Mid-Barataria Diversion (MBD) with a constant discharge of 850 m³ s^-1, were conducted to investigate the impacts of river diversions on salinity gradients and residence times in the estuary. The three-month average salinity indicated that surface …

First-Principles Study On The Catalytic Role Of Cerium Dioxide In The Conversion Of Organic Compounds, Chuanlin Zhao

LSU Doctoral Dissertations

Ceria is an earth-abundant material that has been widely used in heterogeneous catalysis, environmental catalysis, and energy applications thanks for its ability to readily convert between different oxidation states. The objective of this study is to theoretically elucidate the reaction mechanisms for the conversion of model organic compounds on ceria, in order to gain insights for the design of cost-effective and selective ceria-based catalysts. Acetaldehyde, acetic acid, and para-nitrophenyl phosphate monoester were selected as the model compounds to probe ceria surfaces. Density functional theory calculations can provide accurate predictions of adsorption and reaction energetics, which can be used to …

Soybean Response To Dicamba: Associated Injury Criteria And Development Of A Model To Predict Yield Loss, Matthew Ryan Foster

LSU Doctoral Dissertations

In research conducted using indeterminate soybean [Glycine max (L.) Merr.], fourteen injury criteria observed following dicamba at 0.6 to 280 g ae ha^-1 (1/1000 to ½ of 560 g ha^-1 use rate) were rated using a scale of 0= no injury, 1= slight, 2= slight to moderate, 3= moderate, 4= moderate to severe, and 5= severe. Greatest crop injury 15 d after treatment (DAT) was observed following dicamba applied at 0.6 to 4.4 g ha^-1 at V3/V4 for upper canopy pale leaf margins (3.8 to 4.2) and at R1/R2 for terminal leaf cupping (4.1 to 5.0) …

Thermal And Mechanical Energy Harvesting Using Lead Sulfide Colloidal Quantum Dots, Taher Ghomian

LSU Doctoral Dissertations

The human body is an abundant source of energy in the form of heat and mechanical movement. The ability to harvest this energy can be useful for supplying low-consumption wearable and implantable devices. Thermoelectric materials are usually used to harvest human body heat for wearable devices; however, thermoelectric generators require temperature gradient across the device to perform appropriately. Since they need to attach to the heat source to absorb the heat, temperature equalization decreases their efficiencies. Moreover, the electrostatic energy harvester, working based on the variable capacitor structure, is the most compatible candidate for harvesting low-frequency-movement of the human body. …

Velocity-Resolved Reverberation Mapping Of Five Bright Seyfert 1 Galaxies, G. De Rosa, M. M. Fausnaugh, C. J. Grier, B. M. Peterson, K. D. Denney, Keith Horne, M. C. Bentz, S. Ciroi, Elena Dalla Bontà, M. D. Joner, S. Kaspi, C. S. Kochanek, R. W. Pogge, S. G. Sergeev, M. Vestergaard, S. M. Adams, J. Antognini, C. Araya Salvo, E. Armstrong, J. Bae, A. J. Barth, T. G. Beatty, A. Bhattacharjee, G. A. Borman, T. A. Boroson, M. C. Bottorff, J. E. Brown, J. S. Brown, M. S. Brotherton, C. T. Coker, C. Clanton, V. Cracco, S. M. Crawford

Faculty Publications

We present the first results from a reverberation-mapping campaign undertaken during the first half of 2012, with additional data on one active galactic nucleus (AGN) (NGC 3227) from a 2014 campaign. Our main goals are (1) to determine the black hole masses from continuum-Hβ reverberation signatures, and (2) to look for velocity-dependent time delays that might be indicators of the gross kinematics of the broad-line region. We successfully measure Hβ time delays and black hole masses for five AGNs, four of which have previous reverberation mass measurements. The values measured here are in agreement with earlier estimates, though there is …

R1 Retrotransposons In The Nucleolar Organizers Of Drosophila Melanogaster Are Transcribed By Rna Polymerase I Upon Heat Shock, Himanshu S. Raje, Molly E. Lieux, Patrick J. Dimario

Faculty Publications

The ribosomal RNA genes (rDNA) of Drosophila melanogaster reside within centromere-proximal nucleolar organizers on both the X and Y chromosomes. Each locus contains between 200–300 tandem repeat rDNA units that encode 18S, 5.8S, 2S, and 28S ribosomal RNAs (rRNAs) necessary for ribosome biogenesis. In arthropods like Drosophila, about 60% of the rDNA genes have R1 and/or R2 retrotransposons inserted at specific sites within their 28S regions; these units likely fail to produce functional 28S rRNA. We showed earlier that R2 expression increases upon nucleolar stress caused by the loss of the ribosome assembly factor, Nucleolar Phosphoprotein of 140 kDa (Nopp140). …

Influence Of Salinity, Sunlight, And Sediment On The Toxicity Of Pesticides In Three Non-Target Organisms, Emily Noelle Vebrosky

LSU Doctoral Dissertations

Pesticides used in the United States must undergo registration by the United States Environmental Protection Agency (USEPA), after a multitude of analyses ranging from environmental fate to aquatic toxicological impacts to human risk exposure. Testing varies for each chemical, some requiring more testing than others. In many cases, environmental factors are restricted in the analysis of chemical behavior and organismal testing is limited to larvae. Many pesticides are formulated to breakdown in the environment by means of photolysis, hydrolysis, or oxidation, either to ensure low-persistence, limited transport, or to form the active ingredient (pro-pesticides). Environmental influences on chemical behaviors include …

Proton Therapy For Adults With Mediastinal Lymphomas: The International Lymphoma Radiation Oncology Group Guidelines, Bouthaina Shbib Dabaja, Bradford S. Hoppe, John P. Plastaras, Wayne Newhauser, Katerina Rosolova, Stella Flampouri, Radhe Mohan, N. George Mikhaeel, Youlia Kirova, Lena Specht, Joachim Yahalom

Faculty Publications

Among adult lymphoma survivors, radiation treatment techniques that increase the excess radiation dose to organs at risk (OARs) put patients at risk for increased side effects, especially late toxicities. Minimizing radiation to OARs in adults patients with Hodgkin and non-Hodgkin lymphomas involving the mediastinum is the deciding factor for the choice of treatment modality. Proton therapy may help to reduce the radiation dose to the OARs and reduce toxicities, especially the risks for cardiac morbidity and second cancers. Becauseproton therapymay have some disadvantages, identifying the patients and the circumstances that may benefit the most from proton therapy is important. We …

Coupled Chemical Pre-Oxidation And Aerobic Bioremediation Of Buried Mc252 Oil Across A Headlands Beach Profile, Olivia Bramlet

LSU Master's Theses

The release of MC252 crude oil following the Deepwater Horizon event has emphasized the need to investigate factors controlling the extent of contamination degradation in coastal environments. Dam structures created on Fourchon Beach, LA established conditions for PAH and n-alkane accumulation and burial along a vertical profile that persists today due to the anaerobic, often anoxic, and hypersaline conditions of the groundwater. The ability to remove the oxygen limitation present on in situ aerobic biodegradation of buried petroleum-based hydrocarbons in this environment was investigated through the coupled process of chemical oxidation and enhanced bioremediation using a proprietary formulation of activated …

Partner Gender As A Predictor Of Relationship Satisfaction, Sexual Satisfaction, Relationship Commitment, And Attachment Identity Among Women, Amy Leigh Wright

LSU Doctoral Dissertations

Previous research examining overall relationship satisfaction, relationship commitment, and sexual satisfaction among heterosexual women is well-documented. The theoretical foundation of attachment has also been well-established within relationship research among heterosexual women. However, little to no published reports examine such variables among women currently in same-sex relationships. Furthermore, virtually no reports assess for any differences in attachment identity based on the gender of women’s romantic partners. This study therefore sought to identify any interrelationships between relationship satisfaction, relationship commitment, sexual satisfaction, and attachment identity (measured using the dimensions of avoidance and anxiety) among two groups of women based on their partner’s …

Hydrological Connectivity In Vegetated River Deltas: The Importance Of Patchiness Below A Threshold, Kyle Wright, Matthew Hiatt, Paola Passalacqua

Faculty Publications

No abstract provided.

Galveston Bay And Coastal Ocean Optical-Geochemical Response To Hurricane Harvey From Viirs Ocean Color, Eurico J. D’Sa, Ishan Joshi, Bingqing Liu

Faculty Publications

Dissolved and particulate organic carbon, suspended particulate matter concentrations, and their optical proxies colored dissolved organic matter absorption and backscattering coefficients were studied in Galveston Bay, Texas, following the extreme flooding of Houston and surrounding areas due to Hurricane Harvey (25–29 August 2017) using field and ocean color observations. A three-step empirical-semianalytic algorithm for determination of colored dissolved organic matter absorption and backscattering coefficients revealed the dynamics of dissolved organic carbon and particle distribution from Visible and Infrared Imaging Radiometric Suite ocean color. Environmental drivers, especially floodwater discharge and winds, strongly influenced the spatiotemporal distribution of dissolved/particulate material in the …

An Evaluation Of Sciaenid Growth In The Gulf Of Mexico, Shane Flinn

LSU Master's Theses

Growth models estimate life history parameters that are used in the management of fisheries stocks. The most commonly used growth model in fisheries is the von Bertalanffy growth model (VBGM), yet it has been shown to provide a poor fit for length-at-age data of some species and other models exist. I reviewed 196 peer-reviewed age and growth studies and 50 NOAA stock assessments to examine temporal trends in the use of growth models and model selection in fisheries. I found that the use of multi-model frameworks has increased since the year 2000 and information theoretic approaches are replacing goodness-of-fit and …

Iron-Sulfur Cluster Biogenesis And Iron Homeostasis In Escherichia Coli, Jing Yang

LSU Doctoral Dissertations

Iron-sulfur clusters as key cofactors are involved in multiple cellular processes, such as central metabolism and respiration, gene regulation and DNA repair. In Escherichia coli, iron-sulfur clusters are assembled by a group of dedicated proteins. While the sulfide in iron-sulfur clusters is derived from L-cysteine via cysteine desulfurase IscS, the iron source still remains unknown. It has been proposed that IscA and its paralog SufA may act as iron chaperones for iron-sulfur cluster biogenesis. The first part of this work focuses on the interplay between cysteine desulfurase IscS and iron chaperons IscA/SufA. The results show that deletion of IscA/SufA …

Aldosterone Mediated Regulation Of Epithelial Sodium Channel (Enac) Subunits In The Rat Hypothalamus, Natalie J. Mills, Kaustubh Sharma, Masudul Haque, Meagan Moore, Ryoichi Teruyama

Faculty Publications

© 2018 IBRO Current evidence suggests that the epithelial Na + channel (ENaC) in the brain plays a significant role in the development of hypertension. ENaC is present in vasopressin (VP) neurons in the hypothalamus, suggesting that ENaC in VP neurons is involved in the regulation of blood pressure. Our recent study demonstrated that high dietary salt intake caused an increase in the expression and activity of ENaC that were responsible for the more depolarized basal membrane potential in VP neurons. A known regulator of ENaC expression, the mineralocorticoid receptor (MR), is present in VP neurons, suggesting that ENaC expression …

Linear Bidentate Ligands (L) With Two Terminal Pyridyl N-Donor Groups Forming Pt(Ii)Lcl2 Complexes With Rare Eight-Membered Chelate Rings, Kokila Ranasinghe, Patricia A. Marzilli, Svetlana Pakhomova, Luigi G. Marzilli

Faculty Publications

Copyright © 2018 American Chemical Society. NMR and X-ray diffraction studies were conducted on Pt(II)LCl2 complexes prepared with the new N-donor ligands N(SO2R)Mendpa (R = Me, Tol; n = 2, 4). These ligands differ from N(H)dpa (di-2-picolylamine) in having the central N within a tertiary sulfonamide group instead of a secondary amine group and having Me groups at the 6,6′-positions (n = 2) or 3,3′,5,5′-positions (n = 4) of the pyridyl rings. The N(SO2R)3,3′,5,5′-Me4dpa ligands are coordinated in a bidentate fashion in Pt(N(SO2R)3,3′,5,5′-Me4dpa)Cl2 complexes, forming a rare eight-membered chelate ring. The sulfonamide N atom did not bind to Pt(II), consistent …

Genome-Wide Screening Identifies Genes And Biological Processes Implicated In Chemoresistance And Oncogene-Induced Apoptosis, Tengyu Ko

LSU Doctoral Dissertations

Anti-proliferative responses such as senescence and apoptosis are often used by normal cells to combat oncogenic insults and to prevent tumorigenesis. However, oncogenic mutations are frequently found in cancers, suggesting that additional mutations may occur to facilitate the bypass of these anti-proliferative responses. It is believed that some of these additional mutations may also contribute to the chemoresistance of cancers. This dissertation focused on identifying novel genes and biological processes implicated in chemoresistance and tumorigenesis.

Cisplatin-based chemotherapeutic regimens are frequently used for treatments of solid tumors. However, tumor cells may have inherent or acquired resistance to cisplatin, and the underlying …

The Sedimentology And Origins Of A Giant Mass Transport Complex: The Nataraja Slide, Arabian Sea, Sarah Dailey

LSU Master's Theses

A giant mass transport complex (MTC) was recently discovered in the eastern Arabian Sea exceeding in volume all but one other known complex on passive margins worldwide. The complex, named the Nataraja Slide, was drilled by IODP Expedition 355 in two locations where it is ~300 m (Site U1456) and ~200 m thick (Site U1457). The top is defined by the presence of both reworked microfossil assemblages and deformation structures, such as folding and faulting. The deposit consists of two main phases of mass wasting, each which consists of smaller pulses, with generally fining upward cycles, all emplaced just prior …

A Review Of Current Knowledge Concerning The Breeding And Summer Distribution Of The Cordilleran Flycatcher (Empidonax Occidentalis) In Mexico, Harold F. Greeney, Matthew J. Miller, Charles Van Riper Iii

Occasional Papers of the Museum of Natural Science, Louisiana State University

The Cordilleran Flycatcher (Empidonax occidentalis) is one of many North American birds whose distribution crosses the US–Mexican border and for which little is presently known about summer distribution and breeding biology south of this border. In addition, the Cordilleran Flycatcher presents ornithologists with a number of challenging questions surrounding its taxonomy, migration, distribution, population structure, and species limits. In particular, there remains a good deal of uncertainty concerning the species-level relationships, seasonal movements, and the wintering and breeding distributions of both recognized subspecies of Cordilleran Flycatcher in Mexico. Using field observations, a thorough review of the literature, and …

Religion, Racism, And Ecological Stress Among African-American Families: A Qualitative Analysis Of Perceptions And Coping Strategies, Johnnie W. Jones

LSU Doctoral Dissertations

ABSTRACT

Americans do not reside in what many consider now a Post-Racial society. A remarkable number of researchers found that African Americans are more likely than any other racial group to experience racism, manifested by racist attitudes and practices, which negatively affect their physical, mental, and emotional wellbeing (health). Very importantly, numerous scholarly works have examined racism and Black women qualitatively. Unfortunately, less has been known about the personal processes and meaning-making mechanisms of Black married couples and African American males in terms of how they cope with racism, and ecological stress. To address this gap, this study uses qualitative …