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A Membrane Transporter Required For Quorum Sensing And Virulence Of The Rice Pathogen Burkholderia Glumae, Asif Iqbal

LSU Doctoral Dissertations

Burkholderia glumae is a Gram-negative bacterium causing bacterial panicle blight (BPB) in rice. BPB can cause severe damage to rice and reduce rice yield up to 75%, while no effective treatment has been developed to control the disease. B. glumae produces and secretes an essential virulence factor, toxoflavin, which is mainly responsible for the symptoms of BPB. Synthesis and transport of toxoflavin are regulated in a quorum-sensing dependent manner. Members of the DedA superfamily are putative membrane transporters and found in nearly all species. Mutation of dedA in Burkholderia species results in sensitivity to colistin, an antibiotic belonging to the …

Verb Diversities Of Children With And Without Developmental Language Disorder: A Study Of Language Samples, Caitlyn J. Kearns

LSU Master's Theses

Background: There have been numerous studies that have researched word learning in children with Developmental Language Disorder (DLD). These studies have found that children with DLD present with higher vocabulary deficits compared to their typically developing (TD) peers. Many of these studies’ results suggest that verb learning is the most difficult word type to comprehend in early language development for both TD children and children with DLD. This current study aims to examine verb use in children with and without DLD and to specifically examine their usage of GAP verbs. Methods: Participants included 36 children, 18 TD and 18 DLD …

The Effect Of Word-Learning Biases On Early Vocabulary Acquisition In Young Children On The Autism Spectrum, Claire C. Bourgeois

LSU Master's Theses

Background: Vocabulary composition and word-learning biases are closely interrelated in typical development. Such word-learning biases are influenced by perceptually and conceptually salient word features, including imageability, concreteness, iconicity, and attention to shape. Autistic children often have delayed language acquisition, but there is currently little research examining the underlying mechanisms autistic children use to acquire words. The current study aimed to examine the noun composition of autistic children across a range of vocabulary sizes by examining associations between expressive noun vocabulary size and imageability, iconicity, concreteness and evidence for the shape bias, and to examine whether these patterns differ from their …

Simulation Modeling Of A High-Throughput Oyster Cryopreservation Pathway, Sarah Bodenstein, Isabelina Nahmens, Terrence R. Tiersch

Faculty Publications

The genetic resources of oysters in Louisiana and the Gulf of Mexico are threatened due to high unexplained oyster mortality. Germplasm repositories are collections of cryopreserved genetic material stored alongside associated information that are used to protect genetics resources and facilitate breeding programs in agricultural industries. Therefore, there is great need for oyster repositories. Development of repositories has been slow despite research on high-Throughput cryopreservation protocols because of logistical complexities. The goal of this study was to begin to address the gap between cryopreservation research and repository development in oyster aquaculture by modeling a cryopreservation protocol to understand and improve …

Household Salt Production By The Late Classic Maya: Underwater Excavations At Ta'ab Nuk Na, Heather Mckillop, E. Cory Sills

Faculty Publications

Salt is an essential commodity; archaeological remains around the world attest to the importance of its production, exchange and consumption. Often located in coastal locations, many production sites were submerged by rising seas, including the Paynes Creek Salt Works on the southern Belize coast. Survey and excavation of these sites has identified 'kitchens' for brine boiling, as well as Terminal Classic residential structures at Ek Way Nal. The authors report the discovery of an earlier residential building alongside salt kitchens at the nearby site of Ta'ab Nuk Na. This finding indicates that surplus household production began during the Late Classic, …

Low Levels Of Hybridization Between Domestic And Wild Mallards Wintering In The Lower Mississippi Flyway, J. Brian Davis, Diana C. Outlaw, Kevin M. Ringelman, Richard M. Kaminski, Philip Lavretsky

Faculty Publications

The Mallard (Anas platyrhynchos) duck is a ubiquitous and socio-economically important game bird in North America. Despite their generally abundant midcontinent population, Mallards in eastern North America are declining, which may be partially explained by extensive hybridization with human-released domestically derived game-farm Mallards. We investigated the genetic composition of Mallards in the middle and lower Mississippi flyway, key wintering regions for the species. We found that nearly 30% of wild Mallards carried mitochondrial (mtDNA) haplotypes derived from domestic Mallards present in North America, indicating that the individuals had female game-farm Mallard lineage in their past; however, nuclear results identified only …

Optimizing Self-Pollinated Crop Breeding Employing Genomic Selection: From Schemes To Updating Training Sets, Felipe Sabadin, Julio César Dovale, John Damien Platten, Roberto Fritsche-Neto

Faculty Publications

Long-term breeding schemes using genomic selection (GS) can boost the response to selection per year. Although several studies have shown that GS delivers a higher response to selection, only a few analyze which stage GS produces better results and how to update the training population to maintain prediction accuracy. We used stochastic simulation to compare five GS breeding schemes in a self-pollinated long-term breeding program. Also, we evaluated four strategies, using distinct methods and sizes, to update the training set. Finally, regarding breeding schemes, we proposed a new approach using GS to select the best individuals in each F2 progeny, …

Novel Texture-Based Probabilistic Object Recognition And Tracking Techniques For Food Intake Analysis And Traffic Monitoring, Robert Jacob Dibiano

LSU Doctoral Dissertations

More complex image understanding algorithms are increasingly practical in a host of emerging applications. Object tracking has value in surveillance and data farming; and object recognition has applications in surveillance, data management, and industrial automation. In this work we introduce an object recognition application in automated nutritional intake analysis and a tracking application intended for surveillance in low quality videos. Automated food recognition is useful for personal health applications as well as nutritional studies used to improve public health or inform lawmakers. We introduce a complete, end-to-end system for automated food intake measurement. Images taken by a digital camera are …

Probiotic Characteristics Of Streptococcus Thermophilus And Lactobacillus Delbrueckii Ssp. Bulgaricus As Influenced By Carao (Cassia Grandis), David Paz, Ricardo S. Aleman, Roberto Cedillos, Douglas W. Olson, Kayanush Aryana, Jhunior Marcia, Charles Boeneke

Faculty Publications

Carao is considered a functional ingredient since its bioactive compounds are meaningful in nutritional, pharmacological, and medicinal applications. The objective of this study was to determine the effects of carao pulp powder on the bacterial viability, acid tolerance, bile tolerance, and protease activity of S. thermophilus STI-06 and L. bulgaricus LB-12. M17 broth with 0.5% lactose and MRS broth were used for S. thermophilus and L. bulgaricus, respectively, for determining bacterial viability, acid tolerance, and bile tolerance. Skim milk was used to study the protease activity of both bacteria. The carao was added at 0 (control), 1.3, 2.6, and 5.3 …

Fall 2022 Catalog, Lsu Press

LSU Press Seasonal Catalogs

No abstract provided.

Louisiana Agriculture Fall, 2022

Louisiana Agriculture

Livestock industries contribute $2.5 billion to the state’s economy, and beef cattle production is one of the most important sectors of the state’s agricultural enterprise. LSU AgCenter researchers study how to improve cattle production at research stations across the state. AgCenter Extension agents in every parish connect producers with their findings.

In this issue of Louisiana Agriculture magazine, livestock agents and research faculty describe the many programs they have developed to educate cattle producers and help 4-H’ers raise and show animals. Producers discuss what they have learned from Master Cattleman classes, and writer V. Todd Miller details how some cattle …

Cryopreservation Of Hydractinia Symbiolongicarpus Sperm To Support Community-Based Repository Development For Preservation Of Genetic Resources, Aidan L. Huene, Jack C. Koch, Lucía Arregui, Yue Liu, Matthew L. Nicotra, Virginia M. Weis, Terrence R. Tiersch

Faculty Publications

Hydractinia symbiolongicarpus is an emerging model organism in which cutting-edge genomic tools and resources are being developed for use in a growing number of research fields. One limitation of this model system is the lack of long-term storage for genetic resources. The goal of this study was to establish a generalizable cryopreservation approach for Hydractinia that would support future repository development for other cnidarian species. Specific objectives were to: (1) characterize basic parameters related to sperm quality; (2) develop a generalizable approach for sperm collection; (3) assess the feasibility of in vitro fertilization (IVF) with sperm after refrigerated storage; (4) …

Profiling Of Shelter Campers, Their Attitudes, And Perceptions Towards Environmental Impacts Of Campsite Use And Management: Evidence From National Parks Of Sri Lanka, Priyan Perera, Shashini Tara Mallikage, David Newsome, Richard Vlosky

Faculty Publications

There is a dearth of research describing the campsite user segment and in assessing camp-site users’ perceptions of the bio-physical impacts of campsite use in Sri Lanka. Using a structured questionnaire, we evaluated campsite user characteristics, visitor motivations, behaviors, and how visitor experience is affected by visible biophysical impacts at campsites. Based on underlying visitor motivations derived through a Factor Analysis and Cluster Analysis, we identified three distinct segments of campsite users: Eco-tourists, Prestige seekers, and Adventure seekers. Results indicate that the overall cleanliness of the campsite is an important attribute that affects the visitor experience. The Ecotourist segment reported …

Antimicrobial Resistant Bacteria In Shrimp And Shrimp Farms Of Bangladesh, Murshida Khan, Sulav Indra Paul, Md Mahbubur Rahman, Julie Anderson Lively

Faculty Publications

The purpose of this study was to investigate the presence of pathogenic bacteria, specifically Escherichia coli and Salmonella and Vibrio species, and their antimicrobial resistance in shrimp aquaculture facilities of Bagerhat (Bangladesh). Sediment samples were collected from both Penaeus monodon and Macrobrachium rosenbergii farms and shrimp samples from the Macrobrachium rosenbergii facility. The abovementioned bacteria were not found, but five Enterobacterales (Proteus penneri, Proteus alimentorum, Morganella morganii, Enterobacter hormaechei subsp. xiangfangensis and Plesiomonas shigelloides) were detected. This is the first documented case of Enterobacter hormaechei subsp. xiangfangensis in a shrimp farm. Nine antibiotics—ampicillin, gentamicin, chloramphenicol, oxytetracycline, nitrofurantoin, levofloxacin, ciprofloxacin, azithromycin, …

Event-Triggered Control Of Robotic Fish With Reduced Communication Rate, Wenyu Zuo, Animesh Chakravarthy, Michael Malisoff, Zheng Chen

Faculty Publications

Underwater robots often need to communicate with external localization sensors. The low bandwidth in such communications is one of the bottlenecks in achieving accurate tracking control. Toward this end, we adopt a novel periodic event-triggered control (PETC) which allows a robotic fish to reduce its communication load in tracking a desired heading angle with position feedback from an external sensor. To design the PETC, a linear state-space model is derived from a nonlinear dynamic model of the robotic fish with a small perturbation assumption. The PETC consists of an observer, state-feedback controller, integrator, event-trigger rule, and predictor. The observer and …

Contrasts Among Cationic Phytochemical Landscapes In The Southern United States, Luis Y. Santiago-Rosario, Kyle E. Harms, Dylan Craven

Faculty Publications

Understanding the phytochemical landscapes of essential and nonessential chemical elements to plants provides an opportunity to better link biogeochemical cycles to trophic ecology. We investigated the formation and regulation of the cationic phytochemical landscapes of four key elements for biota: Ca, Mg, K, and Na. We collected aboveground tissues of plants in Atriplex, Helianthus, and Opuntia and adjacent soils from 51, 131, and 83 sites, respectively, across the southern United States. We determined the spatial variability of these cations in plants and soils. Also, we quantified the homeostasis coefficient for each cation and genus combination, by using mixed-effect models, with …

Genomic Basis For Individual Differences In Susceptibility To The Neurotoxic Effects Of Diesel Exhaust, Alexandra Noël, David G. Ashbrook, Fuyi Xu, Stephania A. Cormier, Lu Lu, James P. O’Callaghan, Shyam K. Menon, Wenyuan Zhao, Arthur L. Penn, Byron C. Jones

Faculty Publications

Air pollution is a known environmental health hazard. A major source of air pollution includes diesel exhaust (DE). Initially, research on DE focused on respiratory morbidities; however, more recently, exposures to DE have been associated with neurological developmental disorders and neurodegeneration. In this study, we investigated the effects of sub-chronic inhalation exposure to DE on neuroinflammatory markers in two inbred mouse strains and both sexes, including whole transcriptome examination of the medial prefrontal cortex. We exposed aged male and female C57BL/6J (B6) and DBA/2J (D2) mice to DE, which was cooled and diluted with HEPA-filtered compressed air for 2 h …

Hd-Tdcs Of Primary And Higher-Order Motor Cortex Affects Action Word Processing, Karim Johari, Nicholas Riccardi, Svetlana Malyutina, Mirage Modi, Rutvik H. Desai

Faculty Publications

The contribution of action-perception systems of the brain to lexical semantics remains controversial. Here, we used high-definition transcranial direct current stimulation (HD-tDCS) in healthy adults to examine the role of primary (left hand motor area; HMA) and higher-order (left anterior inferior parietal lobe; aIPL) action areas in action-related word processing (action verbs and manipulable nouns) compared to non-action-related control words (non-action verbs and non-manipulable nouns). We investigated stimulation-related effects at three levels of semantic processing: subliminal, implicit, and explicit. Broadly, we found that stimulation of HMA and aIPL resulted in relative facilitation of action-related language processing compared to non-action. HMA …

Pest Population Dynamics Are Related To A Continental Overwintering Gradient, Douglas Lawton, Anders S. Huseth, George G. Kennedy, Amy C. Morey, William D. Hutchison, Dominic D. Reisig, Seth J. Dorman, De Shae Dillard, Robert C. Venette, Russell L. Groves, John J. Adamczyk, Izailda Barbosa Dos Santos, Tracey Baute, Sebe Brown, Eric Burkness, Ashley Dean, Galen P. Dively, Hélène B. Doughty, Shelby J. Fleischer, Jessica Green, Jeremy K. Greene, Krista Hamilton, Erin Hodgson, Thomas Hunt, David Kerns, Billy Rogers Leonard, Sean Malone, Fred Musser, David Owens, John C. Palumbo, Silvana Paula-Moraes, Julie A. Peterson, Ricardo Ramirez

Faculty Publications

Overwintering success is an important determinant of arthropod populations that must be considered as climate change continues to influence the spatiotemporal population dynamics of agricultural pests. Using a long-term monitoring database and biologically relevant overwintering zones, we modeled the annual and seasonal population dynamics of a common pest, Helicoverpa zea (Boddie), based on three overwintering suitability zones throughout North America using four decades of soil temperatures: the southern range (able to persist through winter), transitional zone (uncertain overwintering survivorship), and northern limits (unable to survive winter). Our model indicates H. zea population dynamics are hierarchically structured with continental-level effects that …

The Matricellular Protein Sparc Induces Inflammatory Interferon-Response In Macrophages During Aging, Seungjin Ryu, Sviatoslav Sidorov, Eric Ravussin, Maxim Artyomov, Akiko Iwasaki, Andrew Wang, Vishwa Deep Dixit

Clinical Research Faculty Publications

The risk of chronic diseases caused by aging is reduced by caloric restriction (CR)-induced immunometabolic adaptation. Here, we found that the matricellular protein, secreted protein acidic and rich in cysteine (SPARC), was inhibited by 2 years of 14% sustained CR in humans and elevated by obesity. SPARC converted anti-inflammatory macrophages into a pro-inflammatory phenotype with induction of interferon-stimulated gene (ISG) expression via the transcription factors IRF3/7. Mechanistically, SPARC-induced ISGs were dependent on toll-like receptor-4 (TLR4)-mediated TBK1, IRF3, IFN-β, and STAT1 signaling without engaging the Myd88 pathway. Metabolically, SPARC dampened mitochondrial respiration, and inhibition of glycolysis abrogated ISG induction by SPARC …

A Comparison Of Intertidal Metazoan Biodiversity Among Different Salinity Zones Of Louisiana Coastal Marshes, Claudia Husseneder, Patrick Rayle, Benjamin G. Aker, W. Kelley Thomas, Lane D. Foil

Faculty Publications

Tidal marshes are among the most valuable, productive, and vulnerable ecosystems with high biodiversity. Louisiana’s saltmarshes are endangered by natural and man-made stressors, including oil pollution, saltwater intrusion, and land loss due to sea level rise and erosion. Freshwater diversions have been planned to restore sediment input from the Mississippi River to rebuild marsh habitats in South Louisiana. These proposed diversions will undoubtedly change salinity levels, which is a major controlling factor in the distribution of marsh organisms, including those in soil; however, detailed pre-event inventories are lacking. This study describes the diversity of metazoan meiofauna (organisms between 45 and …

Effects Of Sensory Cues On Product Acceptability And Consumer Perceptions, Emotions, And Behavior, Cristhiam Gurdian Curran

LSU Doctoral Dissertations

Visual and cognitive cues can affect overall liking (OL) and consumer perceptions, emotions, and behavior. The first study explored the effect of product color difference on the liking, perception, and purchase intent (PI) of cheese-flavored-tortilla chips (CFTC) formulations (A and B) on serving plates (plastic, foam, and paper). Color differences between formulations influenced crunchiness and saltiness liking and perception, which together with overall flavor liking and formulation, mainly determined CFTC OL. Although having similar fracturability (N) and sodium content, formulation A had higher crunchiness and saltiness likings. PI was influenced by crunchiness, saltiness, and OF liking with 37, 49, and …

The Double-Edged Sword Of Safety Training For Safety Behavior: The Critical Role Of Psychological Factors During Covid-19, Xin Ning, Jiwen Huang, Chunlin Wu, Tong Liu, Chao Wang

Faculty Publications

Safety training (ST) is the primary means of avoiding unsafe behaviors, but it has not achieved the expected impact on improving workplace safety because of the high psychological stress it brings to workers. The coronavirus disease 2019 (COVID-19) further threatens workers’ psychological conditions, thereby diminishing the effectiveness of ST. However, the existing literature has mainly laid emphasis on the bright side of ST and neglected examining its impact on safety behavior (SB) from detrimental psychological factors. Drawing from the conservation of resources theory, a novel two-staged model was established to understand how these psychological factors mediate and moderate the association …

Endothelin-1 As A Novel Target For The Prevention Of Metabolic Dysfunction With Intermittent Hypoxia In Male Participants, Jacqueline K. Limberg, Sarah E. Baker, Humphrey G. Petersen-Jones, Winston Guo, An Huang, Michael D. Jensen, Prachi Singh

Clinical Research Faculty Publications

We examined the effect of intermittent hypoxia (IH, a hallmark feature of sleep apnea) on adipose tissue lipolysis and the role of endothelin-1 (ET-1) in this response. We hypothesized that IH can increase ET-1 secretion and plasma free fatty acid (FFA) concentrations. We further hypothesized that inhibition of ET-1 receptor activation with bosentan could prevent any IH-mediated increase in FFA. To test this hypothesis, 16 healthy male participants (32 ± 5 yr, 26 ± 2 kg/m2) were exposed to 30 min of IH in the absence (control) and presence of bosentan (62.5 mg oral twice daily for 3 days prior). …

Roosting Ecology Of Gould's Wild Turkeys In Southeastern Arizona, Nicholas W. Bakner, Nathan Fyffe, Brittany Oleson, Alex Smallwood, James R. Heffelfinger, Michael J. Chamberlain, Bret A. Collier

Faculty Publications

Availability of suitable roosting sites influences distribution of wild turkeys (Meleagris gallopavo) across the landscape. In semi-arid environments, roosts are limited to riparian corridors capable of supporting trees large enough to provide suitable roost sites. Gould's wild turkeys (M. g. mexicana) are spatially restricted to mountainous semi-arid areas of southwestern United States and Mexico, and information on their distribution and habitat use is limited. We evaluated roost site selection and fidelity of Gould's wild turkeys relative to environmental gradients and forested land cover during 2016–2017 in southeastern Arizona, USA. We monitored 51 global positioning system (GPS)-tagged individuals and collected 7,954 …

Spatiotemporal Patterns Of Male And Female White-Tailed Deer On A Hunted Landscape, Dylan G. Stewart, William D. Gulsby, Stephen S. Ditchkoff, Bret A. Collier

Faculty Publications

Resource selection in sexually dimorphic ungulates is at least partially explained by sex-specific resource requirements and risk aversion strategies. Females generally spend more time in areas with less risk and abundant, high-quality forage due to their smaller body size. However, demographically variable responses to risk are context dependent, and few have concurrently quantified male and female behavior within areas with the same resource base. We captured 111 (54 males, 57 females) adult white-tailed deer (Odocoileus virginianus) from 2009 to 2018 on a site in South Carolina, USA, where hunters were the primary source of adult mortality. We fit each deer …

Adipocyte-Specific Laminin Alpha 4 Deletion Preserves Adipose Tissue Health Despite Increasing Adiposity, Jennifer L. Bailey, David H. Burk, Susan J. Burke, Scott D. Reed, Sujoy Ghosh, Carrie M. Elks

Division of Basic Science Faculty Publications

Laminins are heterotrimeric glycoproteins with structural and functional roles in basement membranes. The predominant laminin alpha chain found in adipocyte basement membranes is laminin α4 (LAMA4). Global LAMA4 deletion in mice leads to reduced adiposity and increased energy expenditure, but also results in vascular defects that complicate the interpretation of metabolic data. Here, we describe the generation and initial phenotypic analysis of an adipocyte-specific LAMA4 knockout mouse (Lama4AKO). We first performed an in-silico analysis to determine the degree to which laminin α4 was expressed in human and murine adipocytes. Next, male Lama4AKO and control mice were fed chow or high-fat …

Climate Trends And Behavior Of A Model Amazonian Terrestrial Insectivore, Black-Faced Antthrush, Indicate Adjustment To Hot And Dry Conditions, Vitek Jirinec, Elisa C. Elizondo, Patricia F. Rodrigues, Philip C. Stouffer

Faculty Publications

Rainforest loss threatens terrestrial insectivorous birds throughout the world's tropics. Recent evidence suggests these birds are declining in undisturbed Amazonian rainforest, possibly due to climate change. Here, we first asked whether Amazonian terrestrial insectivorous birds were exposed to increasingly extreme ambient conditions using 38 years of climate data. We found long-term trends in temperature and precipitation at our study site, especially in the dry season, which was ~1.3°C hotter and 21% drier in 2019 than in 1981. Second, to test whether birds actively avoided hot and dry conditions, we used field sensors to identify periodic intervals of ambient extremes and …

Effectiveness Of Early Time-Restricted Eating For Weight Loss, Fat Loss, And Cardiometabolic Health In Adults With Obesity: A Randomized Clinical Trial, Humaira Jamshed, Felicia L. Steger, David R. Bryan, Joshua S. Richman, Amy H. Warriner, Cody J. Hanick, Corby K. Martin, Sarah Jeanne Salvy, Courtney M. Peterson

Clinical Research Faculty Publications

Importance: It is unclear how effective intermittent fasting is for losing weight and body fat, and the effects may depend on the timing of the eating window. This randomized trial compared time-restricted eating (TRE) with eating over a period of 12 or more hours while matching weight-loss counseling across groups. Objective: To determine whether practicing TRE by eating early in the day (eTRE) is more effective for weight loss, fat loss, and cardiometabolic health than eating over a period of 12 or more hours. Design, Setting, and Participants: The study was a 14-week, parallel-arm, randomized clinical trial conducted between August …

Applied Nutritional Investigationeffects Of Acute Arginine Supplementation On Neuroendocrine, Metabolic, Cardiovascular, And Mood Outcomes In Younger Men: A Double-Blind, Placebo-Controlled Trial, John W. Apolzan, Jesse A. Stein, Jennifer C. Rood, Robbie A. Beyl, Shengping Yang, Frank L. Greenway, Harris R. Lieberman

Clinical Research Faculty Publications

Objectives: Arginine is an amino-acid supplement and precursor for nitric-oxide synthesis, which affects various biologic processes. The objective of this study was to determine the effects of arginine supplementation on growth hormone (GH) and metabolic parameters. Methods: Thirty physically active, healthy men (age 18–39 y; body mass index: 18.5–25 kg/m2) were randomized in a double-blind, placebo-controlled, crossover trial. Arginine (10 g) and placebo (0 g) beverages were consumed after an overnight fast. Blood samples were collected at baseline and 1.5, 3.0, and 24 h after supplementation. The primary outcomes were serum GH and metabolomics. Also, amino acids, glucose, insulin, triacylglycerols, …