Digital Commons Network^™

Third Generation Gamma Camera Spect System, Narayan Bhusal

LSU Master's Theses

Single Photon Emission Computed Tomography (SPECT) is a non-invasive imaging modality, frequently used in myocardial perfusion imaging. The biggest challenges facing the majority of clinical SPECT systems are low sensitivity, poor resolution, and the relatively high radiation dose to the patient. New generation systems (GE Discovery, DSPECT) dedicated to cardiac imaging improve sensitivity by a factor of 5-8. The purpose of this work is to investigate a new gamma camera design with 21 hemi-ellipsoid detectors each with a pinhole collimator for Cardiac SPECT for further improvement in sensitivity, resolution, imaging time, and radiation dose.

To evaluate the resolution of our …

Using Local Fishery Monitoring To Understand Small-Scale Coastal Fisheries In Tanzania, Matthew Robertson

LSU Master's Theses

Nearshore marine fisheries provide the main source of protein for nearly 9 million people in the coastal villages of Tanzania, yet for decades the fisheries have shown signs of overexploitation. These fisheries are small-scale and co-managed by local coastal communities in groups known as Beach Management Units (BMUs). BMUs monitor individual fishing trip data (e.g. gear, vessel, taxa); however, these data have only been analyzed in nationally aggregated statistics and to our knowledge, are not presently used in management decision making. The present thesis aimed to identify the forms of data and information that local fishery monitoring can record about …

Applications Of Computational Models On Studying Particulate Systems, Jielin Yu

LSU Doctoral Dissertations

Particulate systems have been widely studied because of its various phenomena and tight relationship with industry applications. In this dissertation, two types of computational models have been adopted to study two problems with different particulate systems: granular self-organization inside a cylinder driven by an orbital-shaker and the optimal design of bypass line for an industrial-scale 8‑leg polyolefin loop reactor.

In the first study, behavior of both single particle and multiple particles in a rotating cylinder has been modeled by discrete element method (DEM) to understand the mechanism of granular self-organization. Sets of studies have then been performed to study the …

Louisiana Urban And Suburban Homeowners’ Fertilizer Management Behavioral Beliefs, Intentions, And Past Behaviors, Natalie Levy

LSU Doctoral Dissertations

Nutrient runoff of nitrogen and phosphorus from improper lawn and landscape fertilization practices contributes to water quality issues within the Mississippi River drainage basin and the Northern Gulf of Mexico (NRC, 2009a; Robbins & Birkenholtz, 2003). The implementation of fertilizer best management practices has become a critical strategy for reducing nutrient runoff (Carey et al., 2012a; Carey et al., 2013; U.S. EPA, 2005). The purpose of this study was to determine if relationships exist among selected perceptual measures regarding home lawn and landscape fertilizer management practices among Louisiana urban and suburban homeowners. Ajzen’s (1991) Theory of Planned Behavior (TPB) was …

Analytical Models Of Neutron Spectral Fluence, Kerma And Absorbed-Dose For Proton Therapy, Suman Shrestha

LSU Master's Theses

Abstract

Purpose: The accurate prediction of stray neutron dose has become increasingly important as it increases the risk of second cancer development after proton therapy. Previously reported analytical models predicted the quantity dose equivalent, which includes physical and biological considerations but does not explicitly take into account material dependence and variation in the radiation quality. The purpose of this study was to investigate the feasibility of an analytical model of absorbed dose to water from stray neutrons in proton therapy.

Methods: To calculate neutron absorbed dose and kerma in water, the authors developed analytical models of neutron spectral fluence and …

17.3 Full Issue, Taboo Journal

Taboo: The Journal of Culture and Education

No abstract provided.

Culturally Responsive Teaching Across Pk-20: Honoring The Historical Naming Practices Of Students Of Color, Norma Angelica Marrun

Taboo: The Journal of Culture and Education

No abstract provided.

Structure Based Modulation Of Electron Dynamics In Meso-(4-Pyridyl)-Bodipys: A Computational And Synthetic Approach, Daniel J. Lamaster, Nichole E.M. Kaufman, Adam S. Bruner, M. Graça H. Vicente

Faculty Publications

© 2018 American Chemical Society. The effects of structural modification on the electronic structure and electron dynamics of cationic meso-(4-pyridyl)-BODIPYs were investigated. A library of 2,6-difunctionalized meso-(4-pyridyl)-BODIPYs bearing various electron-withdrawing substituents was designed, and DFT calculations were used to model the redox properties, while TDDFT was used to determine the effects of functionalization on the excited states. Structural modification was able to restructure the low-lying molecular orbitals to effectively inhibit d-PeT. A new meso-(4-pyridyl)-BODIPY bearing 2,6-dichloro groups was synthesized and shown to exhibit enhanced charge recombination fluorescence. The fluorescence enhancement was determined to be the result of functionalization modulating the …

Soil Erodibility Differs According To Heritable Trait Variation And Nutrient-Induced Plasticity In The Salt Marsh Engineer Spartina Alterniflora, Brittany M. Bernik, John H. Pardue, Michael J. Blum

Faculty Publications

Use of landform engineers for habitat restoration has often resulted in unanticipated outcomes. It is possible that departures from expectation arise because applications do not adequately account for the influence of heritable and non-heritable phenotypic variation on ecosystem attributes. In this study, we performed a common garden greenhouse experiment to determine whether soil shear strength—a characteristic linked to erosion resistance—varies according to heritable and plastic trait expression in Spartina alterniflora grown under contrasting nutrient regimes. We detected heritable variation across a broad spectrum of functional traits, including nutrient uptake. We also found that S. alterniflora exhibited trait-specific differences in nutrient-induced …

The Effects Of Biochar And Nitrogen Stabilizers Application On Forage Crop Growth, Greenhouse Gas Emission And Soil Quality, Joseph Elias Rodrigues Mikhael

LSU Doctoral Dissertations

ABSTRACT

Forage systems are important for animal production. Nitrogen fertilization and herbicides use has led to a significant increase in forage production. Therefore, this study aimed to investigate the effects of biochar and N-(n-butyl) thiophosphoric triamide + dicyandiamide (NBPT+DCD) application on manure and urea fertilized soil by focusing on nitrogen fertilizer efficiency use, greenhouse gases emissions, microbial community, soil aggregate stability, and organic carbon functional groups. In addition, herbicides effect on greenhouse gases emission was assessed. Biochar and NBPT+DCD increased nitrogen use efficiency of both fertilizers managements and reduced the N₂O emissions following manure fertilization. However, NBPT+DCD was …

Verification And Evaluation Of A Passive Intensity Modulation Device For Bolus Conformal Therapy, Elizabeth Noel Hilliard

LSU Master's Theses

Purpose: Bolus electron conformal therapy (BECT) provides effective radiation treatment for superficial cancers and other diseases close to the skin surface, but can have as great as a 30% planning target volume (PTV) dose heterogeneity due to scattering from the irregular proximal bolus surface. Intensity modulated (IM) BECT can improve PTV dose homogeneity, but is not currently available. This study fabricated patient-specific passive intensity modulators and validated their delivering planned dose distributions calculated by a modified pencil beam redefinition algorithm (PBRA).

Methods: Two test-patterns and four patient-specific intensity modulators were designed, fabricated, and tested. Dose plans were generated …

Effects Of Maternal Nutrition On The Expression Of Genomic Imprinted Genes In Ovine Fetuses, Jingyue (Ellie) Duan, Mingyuan Zhang, Kaleigh Flock, Sahar Al Seesi, Ion Mandoiu, Amanda Jones, Elizabeth Johnson, Sambhu Pillai, Maria Hoffman, Katelyn Mcfadden, Hesheng Jiang, Sarah Reed, Kristen Govoni, Steve Zinn, Zongliang Jiang, Xiuchun (Cindy) Tian

Faculty Publications

© 2018, © 2018 The Author (s). Published by Informa UK Limited, trading as Taylor & Francis Group. Genomic imprinting is an epigenetic phenomenon of differential allelic expression based on parental origin. To date, 263 imprinted genes have been identified among all investigated mammalian species. However, only 21 have been described in sheep, of which 11 are annotated in the current ovine genome. Here, we aim to i) use DNA/RNA high throughput sequencing to identify new monoallelically expressed and imprinted genes in day 135 ovine fetuses and ii) determine whether maternal diet (100%, 60%, or 140% of National Research Council …

Diel Patterns Of Variable Fluorescence And Carbon Fixation Of Picocyanobacteria Prochlorococcus-Dominated Phytoplankton In The South China Sea Basin, Yuyuan Xie, Edward A. Laws, Lei Yang, Bangqin Huang

Faculty Publications

The various photosynthetic apparatus and light utilization strategies of phytoplankton are among the critical factors that regulate the distribution of phytoplankton and primary productivity in the ocean. Active chlorophyll fluorescence has been a powerful technique for assessing the nutritional status of phytoplankton by studying the dynamics of photosynthesis. Further studies of the energetic stoichiometry between light absorption and carbon fixation have enhanced understanding of the ways phytoplankton adapt to their niches. To explore the ecophysiology of a Prochlorococcus-dominated phytoplankton assemblage, we conducted studies of the diel patterns of variable fluorescence and carbon fixation by phytoplankton in the oligotrophic South China …

Improved Growth Estimates For Lethrinus Harak: Measuring Increments, Adjusting Ages, And Fitting Flexible Growth Models, Stephen Midway

Faculty Publications

No abstract provided.

Fishing Pressure And Species Traits Affect Stream Fish Invasions Both Directly And Indirectly, Brandon K. Peoples, Stephen R. Midway, Brian Leung

Faculty Publications

No abstract provided.

The Potential For Cryptic Population Structure To Sustain A Heavily Exploited Marine Flatfish Stock, Stephen R. Midway, J. Wilson White, Frederick S. Scharf

Faculty Publications

Complex spatial structure is widely viewed as an attribute that can contribute to stability in fish populations. Depending on aspects of stock demography and productivity, the existence of complete or partial spatial refugia can enable population persistence when faced with high rates of exploitation. The Southern Flounder Paralichthys lethostigma has been harvested extensively by inshore fisheries in North Carolina for more than three decades, with estimates of fishing mortality (F) surpassing 2.0 year⁻¹ in several years and systems. Potential hypotheses to explain population persistence under heavy exploitation include high levels of recruitment at low stock sizes (high steepness) and/or …

Functional Analysis Of Short Linear Motifs In The Plant Cyclin-Dependent Kinase Inhibitor Siamese, Narender Kumar, Renee Dale, Daniel Kemboi, Elizabeth A. Zeringue, Naohiro Kato, John C. Larkin

Faculty Publications

© 2018 American Society of Plant Biologists. All rights reserved. Endoreplication, a modified cell cycle in which DNA is replicated without subsequent cell division, plays an important but poorly understood role in plant growth and in plant responses to biotic and abiotic stress. The Arabidopsis (Arabidopsis thaliana) SIAMESE (SIM) gene encodes the first identified member of the SIAMESE-RELATED (SMR) family of cyclin-dependent kinase inhibitors. SIM controls endoreplication during trichome development, and sim mutant trichomes divide several times instead of endoreplicating their DNA. The SMR family is defined by several short linear amino acid sequence motifs of largely unknown function, and …

Designing Agricultural Economics And Agribusiness Undergraduate Programs, Jeffrey M. Gillespie, Maria Bampasidou

Faculty Publications

© 2018 The Author(s). This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence. Agricultural economics and agribusiness (AEAB) programs offer their graduates unique exposure to agricultural markets, policy, and production systems, which differentiates them from business programs. Despite the advantages associated with AEAB degrees, a significant challenge universities and AEAB graduates face is a general lack of recognition of what agricultural economics is and what an agricultural economist does. Using data collected from U.S. 1862 and 1890 land grant universities, we stress the importance of designing effective AEAB curricula based on enrollment trends, …

Mitochondrial Unfolded Protein Response Gene Clpp Is Required To Maintain Ovarian Follicular Reserve During Aging, For Oocyte Competence, And Development Of Pre-Implantation Embryos, Tianren Wang, Elnur Babayev, Zongliang Jiang, Guangxin Li, Man Zhang, Ecem Esencan, Tamas Horvath, Emre Seli

Faculty Publications

© 2018 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd. Caseinolytic peptidase P mediates degradation of unfolded mitochondrial proteins and activates mitochondrial unfolded protein response (mtUPR) to maintain protein homeostasis. Clpp −/− female mice generate a lower number of mature oocytes and two-cell embryos, and no blastocysts. Clpp −/− oocytes have smaller mitochondria, with lower aspect ratio (length/width), and decreased expression of genes that promote fusion. A 4-fold increase in atretic follicles at 3 months, and reduced number of primordial follicles at 6–12 months are observed in Clpp −/− ovaries. This is associated …

The 6xabre Synthetic Promoter Enables The Spatiotemporal Analysis Of Aba-Mediated Transcriptional Regulation, Rui Wu, Lina Duan, José L. Pruneda-Paz, Dong Ha Oh, Michael Pound, Steve Kay, José R. Dinneny

Faculty Publications

© 2018 American Society of Plant Biologists. All rights reserved. The water stress-associated hormone abscisic acid (ABA) acts through a well-defined signal transduction cascade to mediate downstream transcriptional events important for acclimation to stress. Although ABA signaling is known to function in specific tissues to regulate root growth, little is understood regarding the spatial pattern of ABA-mediated transcriptional regulation. Here, we describe the construction and evaluation of an ABSCISIC ACID RESPONSIVE ELEMENT (ABRE)-based synthetic promoter reporter that reveals the transcriptional response of tissues to different levels of exogenous ABA and stresses. Genome-scale yeast one-hybrid screens complemented these approaches and revealed …

Effect Of Dietary Salt Intake On Epithelial Na+ Channels (Enacs) In The Hypothalamus Of Dahl Salt-Sensitive Rats, Natalie J. Mills, Kaustubh Sharma, Katie Huang, Ryoichi Teruyama

Faculty Publications

© 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society. All three epithelial Na+ channel (ENaC) subunits (α, β, and γ) and the mineralocorticoid receptor (MR), a known regulator of ENaC, are located in vasopressin (VP) synthesizing magnocellular neurons in the hypothalamic supraoptic (SON) and paraventricular (PVN) nuclei. Our previous study showed that ENaC mediates a Na+ leak current that affects the steady-state membrane potential of VP neurons. This study was conducted in Dahl salt-sensitive (Dahl-SS) rats to determine if any abnormal responses in the expression of ENaC …

Ablation Of Ezh2 In Neural Crest Cells Leads To Aberrant Enteric Nervous System Development In Mice, Hana Kim, Ingeborg M. Langohr, Mohammad Faisal, Margaret Mcnulty, Caitlin Thorn, Joomyeong Kim

Faculty Publications

© 2018 Kim et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. In the current study, we examined the role of Ezh2 as an epigenetic modifier for the enteric neural crest cell development through H3K27me3. Ezh2 conditional null mice were viable up to birth, but died within the first hour of life. In addition to craniofacial defects, Ezh2 conditional null mice displayed reduced number of ganglion cells in the enteric nervous system. RT-PCR …

Oxytocin Receptor Is Regulated By Peg3, Wesley D. Frey, Kaustubh Sharma, Terri L. Cain, Katsuhiko Nishimori, Ryoichi Teruyama, Joomyeong Kim

Faculty Publications

© 2018 Frey et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Mouse Peg3 encodes a DNA-binding protein involved in the milk letdown process. In the current study, we tested whether PEG3 controls the expression of the oxytocin receptor gene. According to the results, PEG3 directly binds to a genomic region within the 3rd exon of Oxtr, which contains a DNA-binding motif for PEG3. In nursing female mice, removal of PEG3 resulted in …

Emodel-Bdb: A Database Of Comparative Structure Models Of Drug-Target Interactions From The Binding Database, Misagh Naderi, Rajiv Gandhi Govindaraj, Michal Brylinski

Faculty Publications

Background: The structural information on proteins in their ligand-bound conformational state is invaluable for protein function studies and rational drug design. Compared to the number of available sequences, not only is the repertoire of the experimentally determined structures of holo-proteins limited, these structures do not always include pharmacologically relevant compounds at their binding sites. In addition, binding affinity databases provide vast quantities of information on interactions between drug-like molecules and their targets, however, often lacking structural data. On that account, there is a need for computational methods to complement existing repositories by constructing the atomic-level models of drug-protein assemblies that …

A Triple Comparison Between Anticipating Stochastic Integrals In Financial Modeling, Joan Bastons, Carlos Escudero

Communications on Stochastic Analysis

No abstract provided.

The Dual Role Of Amazonian Rivers In The Generation And Maintenance Of Avian Diversity, Luciano N. Naka, Robb T. Brumfield

Faculty Publications

Copyright © 2018 The Authors. The Amazon River and its major tributaries delimit the distributions of hundreds of terrestrial taxa. It remains unclear whether river-bounded distributions and taxon replacements reflect the historical role of rivers in generating species diversity as vicariant forces, or are the result of their role as secondary barriers, maintaining current levels of species diversity by inhibiting gene flow and population introgression. We use a community-wide comparative phylogeographic and phylogenetic approach to address the roles that the Rio Negro and the Rio Branco play in the avian speciation process in the Guiana Shield. Examining 74 pairs of …

Dissolved Carbon In A Large Variety Of Lakes Across Five Limnetic Regions In China, Kaishan Song, Zhidan Wen, Yijun Xu, Hong Yang, Lili Lyu, Ying Zhao, Chong Fang, Yingxin Shang, Jia Du

Faculty Publications

Dissolved carbon in lakes play a vital role in the global carbon cycling. The concentration and dynamics of lake dissolved carbon can be influenced by both the surrounding landscape and a combination of physical, chemical and biological processes within the lakes themselves. From 2009 to 2016, we conducted a large-scale assessment of dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) in 249 lakes across a diverse range of climatic, geopedologic, topographical and hydrological conditions in five Chinese limnetic regions: the East Limnetic Region (ELR), the Northeast Limnetic Region (NLR), the Inner Mongolia-Xinjiang Limnetic Region (MXR), the Yungui Limnetic Region …

Evaluation Of Commercial-Scale Approaches For Cryopreservation Of White Crappie, Pomoxis Annularis, Sperm, Charlie M. Culpepper, Amy M. Guitreau, Shay Allred, Terrence R. Tiersch, Peter J. Allen

Faculty Publications

Crappie, Pomoxis spp., are popular game fish throughout North America and are produced by public and private hatcheries. However, production is limited by a lack of information on tank culture and induced spawning methods. Development of techniques for storage of sperm and in vitro fertilization would increase flexibility in spawning. Therefore, techniques for sperm cryopreservation were examined in white crappie, Pomoxis annularis. Sperm from adult wild white crappie were used to evaluate sperm extender, cryoprotectant agent and concentration, and cooling technique based on post-thaw sperm motility. Percent egg fertilization was also compared between sperm stored in the two best cryopreservation …

Addressing Reproducibility In Cryopreservation, And Considerations Necessary For Commercialization And Community Development In Support Of Genetic Resources Of Aquatic Species, Leticia Torres, Terrence R. Tiersch

Faculty Publications

For the past six decades a repeated cycle of developing new cryopreservation protocols or simply reinventing them to counteract a lack of reproducibility has led to hundreds of published studies that have offered little to the establishment of a genetic resources community for aquatic species. This has hampered repository development and inhibited industrial application. Most protocols were developed without standardized approaches, leading to irreproducible studies and questionable or meaningless comparisons. Thus cryopreservation of germplasm in aquatic species would greatly benefit from strategies to facilitate reproducibility. Our objectives were to: (1) identify major sources of irreproducibility across research, small-scale, repository, and …

Biochar Produced From Mineral Salt-Impregnated Chicken Manure: Fertility Properties And Potential For Carbon Sequestration, Ran Xiao, Jim J. Wang, Lewis A. Gaston, Baoyue Zhou, Jong Hwan Park, Ronghua Li, Syam K. Dodla, Zengqiang Zhang

Faculty Publications

In this study, nutrient properties and carbon sequestration potential of biochars derived from chicken manure (CM) impregnated with mineral salts (calcium chloride, magnesium chloride, ferric chloride) were evaluated. Pretreatment with mineral salts reduced phosphorus (P) availability via the formation of insoluble metal phosphate minerals. Less carbon was lost during the pyrolysis of pretreated CM, and the produced biochars (BCCa, BCMg, and BCFe) were more stable (i.e., reduced C loss during chemical oxidation and less CO2 release during incubation) than pristine biochars. Spectroscopic evidence indicated that enhanced biochar stability via metal salt pretreatment before pyrolysis was related to increased aromatization and …