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A Model-Based Framework For The Smart Manufacturing Of Polymers, Santiago D. Salas Ortiz

LSU Doctoral Dissertations

It is hard to point a daily activity in which polymeric materials or plastics are not involved. The synthesis of polymers occurs by reacting small molecules together to form, under certain conditions, long molecules. In polymer synthesis, it is mandatory to assure uniformity between batches, high-quality of end-products, efficiency, minimum environmental impact, and safety. It remains as a major challenge the establishment of operational conditions capable of achieving all objectives together. In this dissertation, different model-centric strategies are combined, assessed, and tested for two polymerization systems.

The first system is the synthesis of polyacrylamide in aqueous solution using potassium persulfate …

Morphological And Physiological Characteristics Of Endornavirus-Infected And Endornavirus-Free Near-Isogenic Lines Of Bell Pepper (Capsicum Annuum), C. Escalante, R. A. Valverde

Faculty Publications

Plant endornaviruses are persistent viruses that infect plants without causing symptoms. Although endornaviruses have been reported in many economically important plant species, little is known about the effect they have on their hosts. Bell pepper endornavirus (BPEV) has been reported in cultivated peppers (Capsicum spp.). In commercial cultivars of bell pepper (C. annuum) grown in the United States, this virus is found at prevalence rates of 100%. Two bell pepper near-isogenic lines (NILs), one BPEV-infected and the other BPEV-free, were generated and used to investigate the type of symbiotic relationship between BPEV and bell pepper. Selected morphological and physiological characteristics …

Internal Versus External Predictors Of Physical Activity In Youth, Paige Marie Ryan

LSU Doctoral Dissertations

Physical activity (PA) participation has been linked to broad health benefits including reduced risk of chronic diseases (Centers for Disease Control [CDC], 2008). PA participation is important for youth as it sets the precedent for continued engagement and improved long-term health. Nonetheless, adolescents have some of the lowest rates of physical activity, and subsequently obesity rates in youth have exponentially increased in the past few decades (CDC, 2013). Therefore, determining predictors of PA for adolescents is of vital importance. Many studies focus on barriers to PA in youth, but few include both facilitating and inhibiting factors of youth PA participation. …

Framework For Algorithmically Optimizing Longitudinal Health Outcomes: Examples In Cancer Radiotherapy And Occupational Radiation Protection, Lydia Joyce Wilson

LSU Doctoral Dissertations

Background: Advancements in the treatment of non-infectious disease have enabled survival rates to steadily increase in recent decades (e.g., diabetes, heart disease, and cancer). Epidemiological studies have revealed that the treatments for these diseases can have life-threatening and/or life–altering effects. Thus, realizing the full beneficial potential of advanced treatments necessitates new tools to algorithmically consider all major components of the health outcome, including benefit and detriment. The goal of this dissertation was to develop a framework for improving projected health outcomes following planned radiation exposures in consideration of all beneficial and detrimental, early and late, and fatal and non-fatal …

Do Aquatic Macrophytes Limit The Invasion Potential Of Exotic Species In Pantanal Grasslands?, Francielli Bao, Tracy Elsey-Quirk, Marco Antonio De Assis, Evaldo Benedito De Souza, Arnildo Pott

Faculty Publications

No abstract provided.

An Ensemble Of Lipoxygenase Structures Reveals Novel Conformations Of The Fe Coordination Sphere, Svetlana Pakhomova, William E. Boeglin, David B. Neau, Sue G. Bartlett, Alan R. Brash, Marcia E. Newcomer

Faculty Publications

© 2019 The Protein Society The regio- and stereo-specific oxygenation of polyunsaturated fatty acids is catalyzed by lipoxygenases (LOX); both Fe and Mn forms of the enzyme have been described. Structural elements of the Fe and Mn coordination spheres and the helical catalytic domain in which the metal center resides are highly conserved. However, animal, plant, and microbial LOX each have distinct features. We report five crystal structures of a LOX from the fungal plant pathogen Fusarium graminearum. This LOX displays a novel amino terminal extension that provides a wrapping domain for dimerization. Moreover, this extension appears to interfere with …

Patchy Fires Promote Regeneration Of Longleaf Pine (Pinus Palustris Mill.) In Pine Savannas, Kevin M. Robertson, William J. Platt, Charles E. Faires

Faculty Publications

© 2019 by the authors. Research Highlights: Spatial patterns of fire spread and severity influence survival of juvenile pines in longleaf pine savannas. Small areas that do not burn during frequent fires facilitate formation of patches of even-aged longleaf pine juveniles. These regeneration patches are especially associated with inner portions of openings (gaps) and where canopy trees have died in recent decades. Patterns of prescribed fire can thus have an important influence on stand dynamics of the dominant tree in pine savannas. Background and Objectives: Savannas are characterized by bottlenecks to tree regeneration. In pine savannas, longleaf pine is noted …

Arabinosyl Deacetylase Modulates The Arabinoxylan Acetylation Profile And Secondary Wall Formation, Lanjun Zhang, Chengxu Gao, Frederic Mentink-Vigier, Lu Tang, Dongmei Zhang, Shaogan Wang, Shaoxue Cao, Zuopeng Xu, Xiangling Liu, Tuo Wang, Yihua Zhou, Baocai Zhang

Faculty Publications

© 2019 ASPB. Acetylation, a prevalent modification of cell-wall polymers, is a tightly controlled regulatory process that orchestrates plant growth and environmental adaptation. However, due to limited characterization of the enzymes involved, it is unclear how plants establish and dynamically regulate the acetylation pattern in response to growth requirements. In this study, we identified a rice (Oryza sativa) GDSL esterase that deacetylates the side chain of the major rice hemicellulose, arabinoxylan. Acetyl esterases involved in arabinoxylan modification were screened using enzymatic assays combined with mass spectrometry analysis. One candidate, DEACETYLASE ON ARABINOSYL SIDECHAIN OF XYLAN1 (DARX1), is specific for arabinosyl …

A Gradient Of Pollination Specialization In Three Species Of Bolivian Centropogon, Laura P. Lagomarsino, Nathan Muchhala

Faculty Publications

© 2019 Botanical Society of America Premise: Closely related plant species with overlapping ranges often experience competition for pollination services. Such competition can select for divergence in floral traits that attract pollinators or determine pollen placement. While most species in Centropogon (Campanulaceae: Lobelioideae) have flowers that suggest adaptation to bat or hummingbird pollination, actual pollinators are rarely documented, and a few species have a mix of traits from both pollination syndromes. We studied the pollination biology of a “mixed-syndrome” species and its co-occurring congeners to examine the relationship between floral traits and visitation patterns for Centropogon. Methods: Fieldwork at two …

Longleaf Pine Patch Dynamics Influence Ground-Layer Vegetation In Old-Growth Pine Savanna, Maria Paula Mugnani, Kevin M. Robertson, Deborah L. Miller, William J. Platt

Faculty Publications

© 2019 by the authors. Old-growth longleaf pine savannas are characterized by diverse ground-layer plant communities comprised of graminoids, forbs, and woody plants. These communities co-exist with variable-aged patches containing similar-aged trees of longleaf pine (Pinus palustris Mill.). We tested the conceptual model that physical conditions related to the cycle of longleaf pine regeneration (stand structure, soil attributes, fire effects, and light) influence plant species' composition and spatial heterogeneity of ground-layer vegetation. We used a chrono-sequence approach in which local patches represented six stages of the regeneration cycle, from open areas without trees (gaps) to trees several centuries old, based …

Genetics Of Variable Disease Expression Conferred By Inverse Gene-For-Gene Interactions In The Wheat-Parastagonospora Nodorum Pathosystem, Amanda R. Peters Haugrud, Zengcui Zhang, Jonathan K. Richards, Timothy L. Friesen, Justin D. Faris

Faculty Publications

The wheat-Parastagonospora nodorum pathosystem involves the recognition of pathogen-secreted necrotrophic effectors (NEs) by corresponding wheat NE sensitivity genes. This inverse gene-for-gene recognition leads to necrotrophic effector-triggered susceptibility and ultimately septoria nodorum blotch disease. Here, we used multiple pathogen isolates to individually evaluate the effects of the host gene-NE interactions Tan spot necrosis1-Stagonospora nodorum ToxinA (Tsn1-SnToxA), Stagonospora nodorum necrosis1-Stagonospora nodorum Toxin1 (Snn1-SnTox1), and Stagonospora nodorum necrosis3-B genome homeolog1-Stagonospora nodorum Toxin3 (Snn3-B1-SnTox3), alone and in various combinations, to determine the relative importance of these interactions in causing disease. Genetic analysis of a recombinant inbred wheat population inoculated separately with three P. nodorum …

Effect Of Alkali-Enhanced Biochar On Silicon Uptake And Suppression Of Gray Leaf Spot Development In Perennial Ryegrass, Meng Wang, Jim J. Wang, Negar D. Tafti, Clayton A. Hollier, Gerald Myers, Xudong Wang

Faculty Publications

Silicon (Si) is known to alleviate biotic and abiotic stress, and to reduce the development of fungal diseases in a number of different pathosystems. Biochar-based Si fertilizers, especially highly efficient alkali-enhanced biochar for recycling phytolith, has been recently proposed as a stress-alleviating amendment but its evaluation on plant disease development has not been investigated. In this study, several biochar–based Si fertilizers including raw biochar without alkaline enhancement (0 KB), alkali-enhanced biochars with KOH (10 KB), CaO (10CB), and K 2 CO 3 (10K2B) along with commonly-used mineral Si fertilizer wollastonite (WO) and calcium silicate slag (SL) were evaluated in a …

Zinc Toxicity And Iron-Sulfur Cluster Biogenesis In Escherichia Coli, Huangen Ding

Faculty Publications

While zinc is an essential trace metal in biology, excess zinc is toxic to organisms. Previous studies have shown that zinc toxicity is associated with disruption of the (4Fe-4S] clusters in various dehydratases in Escherichia coli. Here, we report that the intracellular zinc overload in E. coli cells inhibits iron-sulfur cluster biogenesis without affecting the preassembled iron-sulfur clusters in proteins. Among the housekeeping iron-sulfur cluster assembly proteins encoded by the gene cluster iscSUA-hscBA-fdx-iscX in E. coli cells, the scaffold IscU, the iron chaperone IscA, and ferredoxin have strong zinc binding activity in cells, suggesting that intracellular zinc overload inhibits iron-sulfur …

Homoeostatic Maintenance Of Nonstructural Carbohydrates During The 2015–2016 El Niño Drought Across A Tropical Forest Precipitation Gradient, Lee Turin Dickman, Nate G. Mcdowell, Charlotte Grossiord, Adam D. Collins, Brett T. Wolfe, Matteo Detto, S. Joseph Wright, José A. Medina-Vega, Devin Goodsman, Alistair Rogers, Shawn P. Serbin, Jin Wu, Kim S. Ely, Sean T. Michaletz, Chonggang Xu, Lara Kueppers, Jeffrey Q. Chambers

Faculty Publications

Nonstructural carbohydrates (NSCs) are essential for maintenance of plant metabolism and may be sensitive to short- and long-term climatic variation. NSC variation in moist tropical forests has rarely been studied, so regulation of NSCs in these systems is poorly understood. We measured foliar and branch NSC content in 23 tree species at three sites located across a large precipitation gradient in Panama during the 2015–2016 El Niño to examine how short- and long-term climatic variation impact carbohydrate dynamics. There was no significant difference in total NSCs as the drought progressed (leaf P = 0.32, branch P = 0.30) nor across …

Polybrominated Diphenyl Ethers (Pbdes) In Ambient Air Samples At The Electronic Waste (E-Waste) Reclamation Site, Ajit Ghimire, Albert Leo N. Dela Cruz, Roberto Wong, Panida Navasumrit, Stephania Cormier, Slawomir M. Lomnicki

Division of Basic Science Faculty Publications

Polybrominated diphenyl ethers (PBDEs) have been used as flame retardants in various building materials, plastic and other polymers, airplanes, electronics, etc. All or some of their congeners have been already banned in many countries, due to their persistency and adverse health effects. In this study, we are focusing on e-wastes as a source of emission of PBDEs in ambient air during reclamation processes. The ambient air particulate matter (PM) samples were collected at and near an e-waste reclamation site in Bangkok, Thailand. Results showed the presence of various homologues, viz: tri-, tetra-, penta-, hexa-, and hepta-PBDEs in both PM2.5 and …

Functional Screening Of Genes From A Halophyte Wild Rice Relative Porteresia Coarctata In Arabidopsis Model Identifies Candidate Genes Involved In Salt Tolerance, Venkata R. Mangu, Disna Ratnasekera, Jonalyn C. Yabes, Rod A. Wing, Niranjan Baisakh

Faculty Publications

High soil salinity is one of the most important environmental stressors, and is an increasing concern under the alarmingly global climate uncertainties. Salinity affects the growth and productivity of food crops, including rice, and ultimately threatens global food security and sustainability. Conventional breeding efforts to develop salt tolerant rice varieties utilizing its primary gene pool have resulted in limited success due to the mutligenic inheritance of salt tolerance traits. On the other hand, Porteresia coarctata, the only halophyte wild rice, offers tremendous opportunities to improve salt tolerance in rice. However, reports on the characterization of its rich genetic resources are …

Balanced Parallel Exploration Of Orthogonal Regions, Wyatt Clements, Costas Busch, Limeng Pu, Daniel Smith, Hsiao Chun Wu

Faculty Publications

We consider the use of multiple mobile agents to explore an unknown area. The area is orthogonal, such that all perimeter lines run both vertically and horizontally. The area may consist of unknown rectangular holes which are non-traversable internally. For the sake of analysis, we assume that the area is discretized into N points allowing the agents to move from one point to an adjacent one. Mobile agents communicate through face-to-face communication when in adjacent points. The objective of exploration is to develop an online algorithm that will explore the entire area while reducing the total work of all k …

Changes In Salivary Antimicrobial Protein Concentrations In Response To Maximal Exercise In Collegiate Swimmers, Katelyn Hardin

Honors Capstones

No abstract provided.

The 3d Scaffold Design Of De Novo Anterior Cruciate Ligament Graft, Dominique Angibeau

Honors Capstones

No abstract provided.

Directed Pore Uptake And Phase Separation Of Surfactant Solutions Under Confinement, Yao Wu, Yingzhen Ma, Lilin He, Gernot Rother, William A. Shelton, Bhuvnesh Bharti

Faculty Publications

The ability of a porous material to uptake and release molecules is determined by the thermodynamic state of preadsorbed surfactants in pore space. However, the effect of spatial confinement on the thermodynamic state of the surfactants is poorly understood. In this study, we use a combination of small-angle neutron scattering experiments and all-atom molecular dynamics simulations to develop a better understanding of the effect of confinement on self-assembly and temperature-induced liquid-liquid phase separation of surfactant solutions. Here, we study the demixing of a model nonionic surfactant triethyleneglycol monohexyl ether (C6E3) in tubular nanopores of the SBA-15 silica material (pore diameter …

Earth History And The Passerine Superradiation, Carl H. Oliveros, Daniel J. Field, Daniel T. Ksepka, F. Keith Barker, Alexandre Aleixo, Michael J. Andersen, Per Alström, Brett W. Benz, Edward L. Braun, Michael J. Braun, Gustavo A. Bravo, Robb T. Brumfield, R. Terry Chesser, Santiago Claramunt, Joel Cracraft, Andrés M. Cuervo, Elizabeth P. Derryberry, Travis C. Glenn, Michael G. Harvey, Peter A. Hosner, Leo Joseph, Rebecca T. Kimball, Andrew L. Mack, Colin M. Miskelly, A. Townsend Peterson, Mark B. Robbins, Frederick H. Sheldon, Luís Fábio Silveira, Brian Tilston Smith, Noor D. White, Robert G. Moyle, Brant C. Faircloth

Faculty Publications

© 2019 National Academy of Sciences. All rights reserved. Avian diversification has been influenced by global climate change, plate tectonic movements, and mass extinction events. However, the impact of these factors on the diversification of the hyperdiverse perching birds (passerines) is unclear because family level relationships are unresolved and the timing of splitting events among lineages is uncertain. We analyzed DNA data from 4,060 nuclear loci and 137 passerine families using concatenation and coalescent approaches to infer a comprehensive phylogenetic hypothesis that clarifies relationships among all passerine families. Then, we calibrated this phylogeny using 13 fossils to examine the effects …

Siah2 Modulates Sex-Dependent Metabolic And Inflammatory Responses In Adipose Tissue To A High-Fat Diet Challenge, Sujoy Ghosh, Jessica L. Taylor, Tamra M. Mendoza, Thanh Dang, David H. Burk, Yongmei Yu, Gail Kilroy, Z. Elizabeth Floyd

Faculty Publications

© 2019 The Author(s). Background: The obesity-related risk of developing metabolic syndrome is higher in males than in females of reproductive age, likely due to estrogen-mediated reduced adipose tissue inflammation and fibrosis with hypertrophied adipocytes. Depletion of the ubiquitin ligase Siah2 reduced white adipose tissue inflammation and improved glucose metabolism in obese male mice. Siah2 is a transcriptional target of estrogen, but data is lacking about the effect of Siah2 on adipose tissue of females. We therefore evaluated the impact of Siah2 deficiency on white and brown adipose tissue in females of reproductive age. Methods: Body composition, adipose tissue morphology, …

An Atlas-Based Method To Predict Three-Dimensional Dose Distributions For Cancer Patients Who Receive Radiotherapy, S. A. Yoganathan, Rui Zhang

Faculty Publications

Due to the complexity of advanced radiotherapy techniques, treatment planning process is usually time consuming and plan quality can vary considerably among planners and institutions. It is also impractical to generate all possible treatment plans based on available radiotherapy techniques and select the best option for a specific patient. Automatic dose prediction will be very helpful in these situations, while there were a few studies of three-dimensional (3D) dose prediction for patients who received radiotherapy. The purpose of this work was to develop a novel atlas-based method to predict 3D dose prediction and to evaluate its performance. Previously treated nineteen …

Inflammatory Reproductive White Adipose Tissue Characterizes The Obese Preeclamptic-Like Bph/5 Mouse Prior To Pregnancy, Kelsey Olson

Honors Capstones

No abstract provided.

Characterizing The Subcellular Localization, Activity, And Physiological Properties Of Α-Carbonic Anhydrases In Arabidopsis Thaliana, Kayla Schwartzenburg

Honors Capstones

No abstract provided.

Synthesis, Characterization, And Evaluation Of Near-Ir Boron Dipyrromethene Bioconjugates For Labeling Of Adenocarcinomas By Selectively Targeting The Epidermal Growth Factor Receptor, Nichole E.M. Kaufman, Qianli Meng, Kaitlin E. Griffin, Sitanshu S. Singh, Achyut Dahal, Zehua Zhou, Frank R. Fronczek, J. Michael Mathis, Seetharama D. Jois, M. Graça H. Vicente

Faculty Publications

Copyright © 2019 American Chemical Society. A series of five boron dipyrromethene (BODIPY) bioconjugates containing an epidermal growth factor receptor (EGFR)-targeted pegylated LARLLT peptide and/or a glucose or biotin ethylene diamine group were synthesized, and the binding capability of the new conjugates to the extracellular domain of EGFR was investigated using molecular modeling, surface plasmon resonance, fluorescence microscopy, competitive binding assays, and animal studies. The BODIPY conjugates with a LARLLT peptide were found to bind specifically to EGFR, whereas those lacking the peptide bound weakly and nonspecifically. All BODIPY conjugates showed low cytotoxicity (IC50 > 94 μM) in HT-29 cells, both …

Building A Better Batture: A Regional Recreational Enhancement Around The Morganza To The Gulf Levee, Taylor N. Fehmel

LSU Master's Theses

Twenty-five years ago, the existing flood protection levees along the Louisiana coastline were removed and construction was started by Terrebonne Levee and Conservation District on a new project called ‘Morganza to the Gulf’ or MTG. This project was undertaken to construct a new flood protection levee system around Louisiana in the communities in Terrebonne and Lafourche Parish. The MTG Levee is one of the first coastal projects in Louisiana to incorporate a risk-based analysis for a double levee system containing both local parish drainage levees and future storm surge levees of MTG. It was designed to protect approximately 250,000 people …

Assessment Of Barrier Island Restoration Planning And Management In The Terrebonne Basin, Louisiana, Sean Russell Williams

LSU Master's Theses

Louisiana holds the majority of the contiguous United States’ coastal wetlands by area, providing significant benefits to users in the form of ecosystem services. Climate change, relative sea level rise, and coastal sediment budget deficits among other anthropogenic processes impact the resilience and sustainability of Louisiana’s coastal systems. Since the implementation of the Coastal Wetland Planning, Protection and Restoration Act (CWPPRA) to restore coastal wetlands in the United States, multiple barrier island restoration projects have taken place in the greater Terrebonne Basin. Amassing a catalog of case studies elucidates the social, ecological, and economic frameworks behind barrier island restoration and …

An Overview Of Rice Qtls Associated With Disease Resistance To Three Major Rice Diseases: Blast, Sheath Blight, And Bacterial Panicle Blight, Seyedeh Soheila Zarbafi, Jong Hyun Ham

Faculty Publications

Rice (Oryza sativa L.) is one of the most important crops that are produced as human food, directly feeding people more than any other crop. Hence, it is important to increase the yield potential of rice through improving the disease resistance to prevailing rice diseases. Blast caused by the fungus Magnaporthe oryzae, sheath blight caused by the fungus Rhizoctonia solani Kühn, and bacterial panicle blight caused by the bacteria Burkholderia glumae and B. gladioli are serious rice diseases in many rice-producing regions. In spite of the chronic damages from these major diseases, the quantitative resistance to each of them is …

The Corridor Des Arts, Kade M. Jones

LSU Master's Theses

Arnaudville is a small rural town in south central Louisiana with a population of 1200. In 2010, the National Endowment of the Arts (NEA) named Arnaudville as one of fourteen cities that were classified as a successful case study of “Creative Placemaking.” The NEA defines creative placemaking as community partnerships that use arts and culture to shape the social, environmental, and economic identity of a place. The NUNU Arts and Culture Collective, a Louisiana Cajun French non-profit arts organization centered in Arnaudville, is the main catalyst of this effort.

Members of NUNU have identified five other rural towns within close …