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Reassessing Nitrogen Management For Maize Production In Mississippi, Camden Dawson Oglesby Dec 2022

Reassessing Nitrogen Management For Maize Production In Mississippi, Camden Dawson Oglesby

Theses and Dissertations

12 N treatments in 2020 and 11 in 2021 were replicated four times over four locations in a randomized complete block design. The first research tested the efficacy of CYG for Mississippi corn (Zea mays L.) production. The optimum N rates were calculated by fitting four models. Differences between the CYG rate and AONR were compared. AONR varied from 134 to 301 kg N ha–1 at different management levels. When we compared the AONR to the CYG rate, the CYG rate over-recommended N in 12 of the 14 possible comparisons. The second study compared different VIs, methods, and sensors at …


Dynamics Of Redox-Driven Molecular Processes In Local And Systemic Plant Immunity, Philip Berg Dec 2022

Dynamics Of Redox-Driven Molecular Processes In Local And Systemic Plant Immunity, Philip Berg

Theses and Dissertations

The work here presents two main parts. In the first part, chapters 1 – 3 focus on dynamical systems modeling in plant immunity, whereas chapters 4 – 6 describe contributions to computational modeling and analysis of proteomics and genomics data. Chapter 1 investigates dynamical and biochemical patterns of reversibly oxidized cysteines (RevOxCys) during effector-triggered immunity (ETI) in Arabidopsis, examines the regulatory patterns associated with Arabidopsis thimet oligopeptidase 1 and 2’s (TOP1 and TOP2), roles in the RevOxCys events during ETI, and analyzes the redox phenotype of the top1top2 mutant. The second chapter investigates the peptidome dynamics during ETI …


Disease Resistance And Productivity In Genetically Improved Loblolly Pine: Results From A Resistance Screening Trial And A Midrotation Comparison Of Genetic Improvement Levels, Stephen W. Goodfellow Dec 2022

Disease Resistance And Productivity In Genetically Improved Loblolly Pine: Results From A Resistance Screening Trial And A Midrotation Comparison Of Genetic Improvement Levels, Stephen W. Goodfellow

Theses and Dissertations

Decades of tree improvement has resulted in genetic gains in loblolly pine productivity, form, and resistance to fusiform rust. The goal of this study was to advance the understanding and applied use of genetic improvement by analyzing inter- and intra-provenances hybrids’ rust resistance and evaluating midrotation performance of varying levels of genetically improved stock types. The first study compares 16 seedlots at the USDA Resistance Screening Center and evaluates rust resistance of controlled-pollinated inter- and intra-provenances crosses, and openpollinated seedlots from three provenances: Western Gulf, Atlantic Coastal, and Interior Piedmont. Post inoculation, one Coastal OP seedlot was resistant and ten …


Evaluating The Impacts Of Waterlogging Stress On Cowpea (Vigna Unguiculata L.) Growth Traits And Physiological Performance, Omolayo Joshua Olorunwa Dec 2022

Evaluating The Impacts Of Waterlogging Stress On Cowpea (Vigna Unguiculata L.) Growth Traits And Physiological Performance, Omolayo Joshua Olorunwa

Theses and Dissertations

The progressive increase in the global population and the rapidly changing climate have put unprecedented pressure on crop production. Cowpea is one of the world’s most important leguminous crops, contributing to food security and environmental sustainability. However, cowpea productivity is limited due to waterlogging stress. The main objective of this study was to explore physiological and biochemical mechanisms to understand how cowpea genotypes respond to waterlogging stress. Four studies were conducted in controlled and field conditions to achieve these objectives. Study 1 characterized the waterlogging tolerance of 30 cowpea genotypes in a controlled environment using 24 morphophysiological parameters with waterlogging …


Evaluation For Using Expended Bioelectrochemical Systems As Soil Amendments For Improved Corn Plant Growth And A Drought Resistant Soil., Jackson Lee Sauers Dec 2022

Evaluation For Using Expended Bioelectrochemical Systems As Soil Amendments For Improved Corn Plant Growth And A Drought Resistant Soil., Jackson Lee Sauers

Theses and Dissertations

A long-held practice is to mix agricultural soil with a soil amendment to improve growing conditions in crops. A common soil amendment is biosolids produced from both municipal and dairy wastewater due to the macro- and micronutrients within it. Both the agricultural and wastewater industries are participating in the Circular Economy concept (CEC). Two experiments explored using expended bioelectrochemical systems (BES) that treated either synthetic dairy wastewater (DWW) or synthetic municipal wastewater (SWW) as soil amendments to improve corn plant growth when treated with three different nutrient treatments: 100%- 50%- and 0% Hoagland Nutrient Solutions. Biochar and used terracotta clay …


Assessing The Legacy Of Erosion And Flood Control Management Efforts On The Fish Assemblages And Physical Conditions Of Yazoo Basin Bluff Hill Streams, Nicky M. Faucheux Dec 2022

Assessing The Legacy Of Erosion And Flood Control Management Efforts On The Fish Assemblages And Physical Conditions Of Yazoo Basin Bluff Hill Streams, Nicky M. Faucheux

Theses and Dissertations

The hills of Yazoo Basin have a long history of land use modification and subsequent erosion and flood control issues. In response, federal actions were taken to address these issues beginning after the Mississippi River flood of 1927. Four major flood control reservoirs were built in 1932-1957, and instream low-drop grade control structures (GCS) were installed beginning in the 1980s. The objective of my dissertation was to ascertain the long-term effects of these efforts on stream fish assemblages and channel morphology. To assess whether the reservoirs affected upstream fish assemblages as barriers to recolonization by fluvial fishes or as source …


The Effects Of Glyphosate Salts And Volatility-Reducing Agents (Vra) On Dicamba Volatility, Nicole Glenn Dec 2022

The Effects Of Glyphosate Salts And Volatility-Reducing Agents (Vra) On Dicamba Volatility, Nicole Glenn

Theses and Dissertations

Dicamba is often tank mixed with glyphosate to increase herbicidal efficacy but may contribute to off-target movement (OTM). In recent years, volatilization has become problematic for dicamba-containing herbicides, resulting in increased regulatory requirements necessitating the use of volatility-reducing agents (VRA) for application. Research was conducted in 2021 and 2022 using low tunnels in a field environment and humidomes in a greenhouse environment to further assess how glyphosate salts and VRAs affect dicamba volatility. Our data indicate that the inclusion of glyphosate to dicamba can increase dicamba volatility, depending on the glyphosate salt used. The inclusion of the evaluated VRAs will …


Assessing Wood Failure In Plywood By Deep Learning/Semantic Segmentation, Ramon Ferreira Oliveira Dec 2022

Assessing Wood Failure In Plywood By Deep Learning/Semantic Segmentation, Ramon Ferreira Oliveira

Theses and Dissertations

The current method for estimating wood failure is highly subjective. Various techniques have been proposed to improve the current protocol, but none have succeeded. This research aims to use deep learning/semantic segmentation using SegNet architecture to estimate wood failure in four types of three-ply plywood from mechanical shear strength specimens. We trained and tested our approach on custom and commercial plywood with bio-based and phenol-formaldehyde adhesives. Shear specimens were prepared and tested. Photographs of 255 shear bonded areas were taken. Forty photographs were used to solicit visual estimates from five human evaluators, and the remaining photographs were used to train …


Healthy Eating Index And Body Fat Distribution, Masar Ozrail Dec 2022

Healthy Eating Index And Body Fat Distribution, Masar Ozrail

Theses and Dissertations

Body fat distribution has been identified as a more significant risk factor for metabolic-related diseases. This study investigated whether body fat distribution affects dietary outcomes (quality and intake), anthropometric measures, body composition, and skin carotenoid levels. A cross-sectional study with 91 female students was conducted. Thirty-one percent of participants (n=28) had an android body fat distribution. Body fat distribution was associated with WC and WHtR (p


The Influence Of Taste Sensitivity To 6-N-Propylthiouracil (Prop) On Anthropometric Measurements, Body Composition, And Eating Behaviors Among Female College Students, Abeer Mohammedsharief Alardawi Dec 2022

The Influence Of Taste Sensitivity To 6-N-Propylthiouracil (Prop) On Anthropometric Measurements, Body Composition, And Eating Behaviors Among Female College Students, Abeer Mohammedsharief Alardawi

Theses and Dissertations

Taste is one of the crucial factors that contributes to shaping eating behaviors and is also one of the leading reasons that affects our preferences to like or dislike some foods that mainly have a bitter taste. Variation in bitter phenotype (tasters and non-tasters) could influence diet quality and in turn body weight, which overall influenced health outcomes. The objective of this study was to identify whether bitter taste phenotype status influences anthropometric measurements, body fat percentage, and eating behaviors (liking and intake) in female college students. In this cross-sectional study (n = 86), female college students aged 18 to …


Efficacy Of Antimicrobial Treatments In Vitro And On Fresh Produce Against Selected Foodborne Pathogens And Microbiome Diversity Amongst Blueberry Farms, Angelica Maria Abdallah Ruiz Dec 2022

Efficacy Of Antimicrobial Treatments In Vitro And On Fresh Produce Against Selected Foodborne Pathogens And Microbiome Diversity Amongst Blueberry Farms, Angelica Maria Abdallah Ruiz

Theses and Dissertations

This study focused on evaluating the antimicrobial activity of chlorine dioxide (ClO2) and different plant-based antimicrobials (carvacrol, thymol, and eugenol as bioactive compounds and muscadine extract- ME and blueberry extract- BBE as plant extracts) against selected foodborne pathogens under in vitro conditions and on produce (spinach and blueberries). In addition, bacterial microbiota associated with blueberries and blueberry farm environments from three different regions: Cundinamarca, Colombia; Mississippi, United States; and Guadalajara, Mexico, was determined. Under in vitro conditions, carvacrol and thymol were more effective (lower MICs and MBCs) than eugenol against Salmonella spp., Escherichia coli O157:H7 (MIC=MBC=0.2 mg/ml), and …


Animal Husbandry In The 21st Century: Application Of Ecological Theory And Precision Technology To Inform Understanding Of Modern Grazing Systems, Ira Lloyd Parsons Dec 2022

Animal Husbandry In The 21st Century: Application Of Ecological Theory And Precision Technology To Inform Understanding Of Modern Grazing Systems, Ira Lloyd Parsons

Theses and Dissertations

Ruminant animals comprise the greatest proportion of herbivores around the world, provide essential ecosystem services and human consumable protein by consuming grass and human inedible dietary fiber. Herbivory pressure alters plant communities and species diversity, effectively making grazing animals ecosystem engineers in dynamic ecosystems. Development of advanced computer processing power coupled with biometric and ecosystem sensors may be employed in the internet of things framework to create an integrated information system designed to inform understanding of grazing system function and animal energy balance. Towards this end, I utilized Bos indicus / Bos taurus crossbred steers (n = 20) across two …


Metagenomic Analysis Of Root-Associated Microbiome Of Healthy And Taproot Decline-Affected Soybeans And Identification Of Healthy Soybean Root Endophytes With Protective Activity Against The Causal Agent, Xylaria Necrophora, Uyen Wesser Dec 2022

Metagenomic Analysis Of Root-Associated Microbiome Of Healthy And Taproot Decline-Affected Soybeans And Identification Of Healthy Soybean Root Endophytes With Protective Activity Against The Causal Agent, Xylaria Necrophora, Uyen Wesser

Theses and Dissertations

Plant roots are associated with a diverse microbial community of bacteria and fungi. The root microbiome communities associate with the root surface or penetrate the superficial layers of root tissues. It is of high agronomic interest to characterize root microbiomes and identify microbes with beneficial effects on plant defense against pathogens. Soybean taproot decline (TRD) is an emerging soil-borne disease caused by a fungus classified as Xylaria necrophora, challenging to control and with devastating effects on yield. Our group has initiated a study of the soybean root microbiome with three primary experiments: (I) perform a comparative study of root …


Attitudes Towards Breastfeeding Among College Students At Mississippi State University, Kristin F. Williford Dec 2022

Attitudes Towards Breastfeeding Among College Students At Mississippi State University, Kristin F. Williford

Theses and Dissertations

Breastfeeding rates in America are lower than other high-income countries, with Mississippi having one of the lowest rates. A survey using the Iowa Infant Feeding Attitude Scale (IIFAS) was distributed twice to Mississippi State University students to understand their breastfeeding attitudes. Attitudes were determined by calculating a composite score and conducting statistical tests for significance. Knowledge between health and non-health related majors were explored by using five statements, and attitudes towards the statement “Breastmilk is the ideal food for babies” were compared across demographics. Of 642 respondents, the composite score was 57.3 out of 85, and all demographics had a …


Effects Of Microcystin-Lr On Channel Catfish (Ictalurus Punctatus) Susceptibility To Microbial Pathogens (Aeromonas Hydrophila And Edwardsiella Piscicida), Alison Marchant Dec 2022

Effects Of Microcystin-Lr On Channel Catfish (Ictalurus Punctatus) Susceptibility To Microbial Pathogens (Aeromonas Hydrophila And Edwardsiella Piscicida), Alison Marchant

Theses and Dissertations

Microcystin-LR is a hepatotoxin produced by cyanobacteria. Aeromonas hydrophila and Edwardsiella piscicida infections are leading causes of losses in market-sized channel catfish (Ictalurus punctatus). These older fish should have natural immunity in place and a predisposing factor is likely a prerequisite for these disease outbreaks. While microcystin-LR rarely causes mortality in warm-water aquaculture, we believe it may be a predisposing factor that leads to bacterial disease outbreaks during the summer months due to its ability to damage the liver. Our study investigated microcystin-LR’s effects on channel catfish susceptibility to these pathogens. We found that a sublethal dose of microcystin-LR induced …


Towards Structured Planning And Learning At The State Fisheries Agency Scale, Caleb A. Aldridge Dec 2022

Towards Structured Planning And Learning At The State Fisheries Agency Scale, Caleb A. Aldridge

Theses and Dissertations

Inland recreational fisheries has grown philosophically and scientifically to consider economic and sociopolitical aspects (non-biological) in addition to the biological. However, integrating biological and non-biological aspects of inland fisheries has been challenging. Thus, an opportunity exists to develop approaches and tools which operationalize planning and decision-making processes which include biological and non-biological aspects of a fishery. This dissertation expands the idea that a core set of goals and objectives is shared among and within inland fisheries agencies; that many routine operations of inland fisheries managers can be regimented or standardized; and the novel concept that current information and operations can …


The Emerging Value Of The Viroid Model In Understanding Plant Responses To Foreign Rnas, Junfei Ma Dec 2022

The Emerging Value Of The Viroid Model In Understanding Plant Responses To Foreign Rnas, Junfei Ma

Theses and Dissertations

RNAs play essential roles in various biological processes. Mounting evidence has demonstrated that RNA subcellular localization and intercellular trafficking govern their functions in coordinating plant growth at the organismal level. Beyond that, plants constantly encounter foreign RNAs (i.e., RNAs from pathogens including viruses and viroids). The subcellular localizations of RNAs are crucial for their function. While numerous types of RNAs (i.e., mRNAs, small RNAs, rRNAs, tRNAs, and long noncoding RNAs) have been found to traffic in a non-cell-autonomous fashion within plants, the underlying regulatory mechanism remains unclear. Viroids are single-stranded circular noncoding RNAs, which entirely rely …


Non-Traditional Adjuvants And Methods For Applying Root-Promoting Compounds In Commercial Cutting Propagation, Anthony Turner Bowden Dec 2022

Non-Traditional Adjuvants And Methods For Applying Root-Promoting Compounds In Commercial Cutting Propagation, Anthony Turner Bowden

Theses and Dissertations

The nursery/greenhouse industry is innovative. There have been several reports in the popular literature of non-traditional adjuvants used in plant propagation; however, these claims have never been evaluated in a scientific setting. Five studies, conducted at the South Mississippi Branch Experiment Station in Poplarville in 2019 and 2021 determined the impact that adding honey to water-soluble auxin solutions and surfactants to foliar applied auxin solutions on physiological responses associated with adventitious root formation. Treatments in studies presented in chapters two and three included three honey sources (multiflora, local, and Manuka). Honey-infused water-soluble auxin solutions affected plant species but not in …


An Evaluation On The Effects Of Additions And Deletions Of Specific Nutrient Management Strategies On Corn Yield At Different Plant Densities, James D. Dew Dec 2022

An Evaluation On The Effects Of Additions And Deletions Of Specific Nutrient Management Strategies On Corn Yield At Different Plant Densities, James D. Dew

Theses and Dissertations

Improved management strategies are needed to increase yield production and quality. The study aimed to determine suitable cultural practices for improved corn production. Experiments were set up at Verona and Stoneville, Mississippi, from 2020 to 2022. Treatments included row configurations (single and twin-row), plant populations (79,000 and 99,000 seeds ha-1), and six combinations of nutrients with or without fungicide. The nutrients evaluated were two nitrogen rates 235 and 314 kg N ha-1, phosphorus 45 kg P ha-1, potassium 112 kg K ha-1, sulfur 22 kg S ha-1, and zinc 11 kg Zn ha-1, and fungicide at 272 ml ha-1. In …


The Use Of 87sr/86sr Isotopic Ratios To Assess Natal Areas And Movement Of Juvenile Gulf Sturgeon Acipenser Oxyrinchus Desotoi In The Pascagoula And Pearl River Systems, Joshua Neary Dec 2022

The Use Of 87sr/86sr Isotopic Ratios To Assess Natal Areas And Movement Of Juvenile Gulf Sturgeon Acipenser Oxyrinchus Desotoi In The Pascagoula And Pearl River Systems, Joshua Neary

Theses and Dissertations

The effects of water and dietary influence, and time duration for discernment, of pectoral fin spine 87Sr/86Sr were evaluated in Atlantic Sturgeon Acipenser oxyrinchus oxyrinchus. Fish were subjected to 87Sr-enriched water (0.1 mg/L) or diet (0.25 migrogram/g or 0.5 microgram/g) for 1, 2, 3, 6, or 12 weeks. Fish were also held at 15 or 25°C to determine if temperature influenced 87Sr/86Sr. Results found fin spine 87Sr/86Sr changed in water after 1 week and diet after 12 weeks suggesting water is the primary influence. In wild Gulf Sturgeon A. o. …


Evaluation Of Soybean [Glycine Max (L.) Merr.] Cultivar Response To Prophylactic Fungicide Application, Steven B. Stoker Dec 2022

Evaluation Of Soybean [Glycine Max (L.) Merr.] Cultivar Response To Prophylactic Fungicide Application, Steven B. Stoker

Theses and Dissertations

Soybean growers in the southern United States commonly deal with disease issues that can limit yield potential. As a result, growers have adopted prophylactic fungicide application targeted at specific growth stages as a standard management practice. However, yield responses to prophylactic applications have become sporadic over time. One major change that has occurred is adoption of cultivars with improved disease tolerances. Therefore, the objective of this research was to evaluate yield response of cultivars representing multiple genetic backgrounds to fungicides applied prophylactically at the R4 soybean growth stage. Experiments were conducted in 2020 and 2021 to determine the yield impact …


United We Stand? Investigating The Impact Of Unified Dues Agreements Between State And National Career & Technical Education (Cte) Professional Organizations On Cte Funding In The Southern States, Justin Ryan Hall Dec 2022

United We Stand? Investigating The Impact Of Unified Dues Agreements Between State And National Career & Technical Education (Cte) Professional Organizations On Cte Funding In The Southern States, Justin Ryan Hall

Theses and Dissertations

Career and Technical Education (CTE) teachers have long been active in lobbying the federal and state governments in support of CTE through their professional organizations, but these are not traditionally considered interest groups. This study sought to determine if the formal relationships—dues agreements—between the two largest national professional organizations, and their state affiliates had an impact on state funding for CTE. The impacts of professional organization unity, membership rates, and lobbying expenses on state-level CTE funding were analyzed through the lens of interest group theory, a subfield of political science. Within this population (N = 13), 1) a link …


Vegetation And Nutritional Changes Over 20 Years Of White-Tailed Deer Exclusion, Gabrielle Nicole Ripa Dec 2022

Vegetation And Nutritional Changes Over 20 Years Of White-Tailed Deer Exclusion, Gabrielle Nicole Ripa

Theses and Dissertations

Knowledge of the impacts of white-tailed deer (Odocoileus virginianus; hereafter deer) as dominant herbivores throughout the Southeastern United States of America is lacking. To address this, three paired experimental units of exclosures and controls were constructed in 2000 on three Wildlife Management Areas across Mississippi within the ecoregions of the Upper Coastal Plain, Lower Coastal Plain, and the Mississippi Alluvial Valley. Vegetation was sampled in the summers of 2000, 2005, and 2021 including vegetation structure, canopy coverage, basal area, and species composition. Additionally, in 2005 and 2021, biomass was sampled to determine potential impacts on nutritional carrying capacity. Among the …


Mapping Forest Structure In Mississippi Using Lidar Remote Sensing, Nitant Rai Dec 2022

Mapping Forest Structure In Mississippi Using Lidar Remote Sensing, Nitant Rai

Theses and Dissertations

This study aimed at evaluating the agreement of spaceborne Light Detection and Ranging (lidar) ICESat-2 canopy height with Airborne Laser Scanning (ALS) derived canopy height to inform about the performance of ICESat-2 canopy height metrics and understand its uncertainties and utilities. The agreement was assessed for different forest types, physiographic regions, a range of percent canopy cover, and diverse disturbance histories. Results of this study suggest that best agreements are found using strong beam data collected at night for canopy height retrieval using ICESat-2. The ICESat-2 showed great potential for estimating canopy heights, particularly in evergreen forests with high canopy …


Empathy And Cultural Involvement As Pathways To Resilience In The Face Of Adverse Childhood Experiences Among Native American Indians, Joy Rodriguez Dec 2022

Empathy And Cultural Involvement As Pathways To Resilience In The Face Of Adverse Childhood Experiences Among Native American Indians, Joy Rodriguez

Theses and Dissertations

The purpose of this research study was to examine two specific pathways to resilience for Native American Indians (NAIs) that have experienced at least one adverse childhood experience (ACE) and are seeking behavioral health services on the Choctaw Indian reservation: empathy and cultural involvement. The study is an examination of the effects of empathy and cultural involvement on the resilience of NAIs with one or more ACEs. The researcher also investigated the type of ACEs reported among adult NAIs seeking behavioral health services on the Mississippi Band of Choctaw Indian (MBCI) Reservation. Lastly, the association between ACEs and resilience was …


Evaluation Of Novel Litter Amendments For Use In The Commercial Broiler Industry, Jorge A. Urrutia Dec 2022

Evaluation Of Novel Litter Amendments For Use In The Commercial Broiler Industry, Jorge A. Urrutia

Theses and Dissertations

Poultry litter amendments (LA) are commonly used to maintain good litter quality; the most common ones; are acidifiers. However, concern over the lifespan of LA acidifiers (d) and corrosive nature revealed a need for alternative LA. Products of interest include biochar (BC), superabsorbent polymers (SAPs), and alum mud (AM). Experiment 1 was a screening study (n=17 treatments, no birds) conducted to determine the optimal application rate/method of BC, SAPs, and AM vs.commercial LA and a control. Most SAPs treatments measured metrics may be similar (i.e., bacteria, water activity) or better (pH) vs. commercial LA (PLT). High inclusions of novel LA …


Effects Of Soil Management Practices On Water Infiltration And Maize Yield To Improve Mississippi River Valley Alluvial Aquifer Sustainability, Jacob Rix Dec 2022

Effects Of Soil Management Practices On Water Infiltration And Maize Yield To Improve Mississippi River Valley Alluvial Aquifer Sustainability, Jacob Rix

Theses and Dissertations

Surface sealing and hardpans in loam soils are problematic in the Mid-South U.S. because of intense tillage. Two experiments quantified the effects of soil management practices on infiltration and maize yield in loam soils. The first study measured the impacts of in-row subsoiling frequency × furrow irrigation frequency. In-row subsoiling significantly improved the infiltration of irrigation but not the infiltration of precipitation. In-row subsoiling with low irrigation frequency is optimal to achieve profitable maize yields while encouraging groundwater conservation. In the second study, six soil management treatments were imposed. For single-ring infiltrometer tests, infiltration rates were different between the two …


Seasonal Trends And Sampling Time Of Day On Overall Microbial Population And Indicator Organisms In Catfish Parts And Catfish Processing Environment, Maria Gabriela Hidalgo-Sindoni Dec 2022

Seasonal Trends And Sampling Time Of Day On Overall Microbial Population And Indicator Organisms In Catfish Parts And Catfish Processing Environment, Maria Gabriela Hidalgo-Sindoni

Theses and Dissertations

Commercial production of catfish is the leading aquaculture industry in the United States. Production in Mississippi, Louisiana, Alabama, and Arkansas representing 96% of the total catfish sales in the USA. In 2017, the USDA-FSIS added testing of generic Escherichia coli and Enterococcus to the sampling of Siluriformes. The incidence of Escherichia coli in fish and seafood has been associated with possible fecal matter contamination. However, this indicator bacteria could also be a part of the natural microflora of catfish ponds where processing plants collect hybrid catfish. Aerobes, Psychrotrophs, Coliforms, Escherichia coli, and Enterobacteriaceae counts among environmental, liquid and fish …


Microstructure And Sensory Attributes Of Rabbiteye Blueberries Subject To Osmotic Dehydration And Two Freezing Methods, Antonio Carlos Garcia Dec 2022

Microstructure And Sensory Attributes Of Rabbiteye Blueberries Subject To Osmotic Dehydration And Two Freezing Methods, Antonio Carlos Garcia

Theses and Dissertations

Frozen, thawed and osmotically-dehydrated highbush (HB) (Vaccinium corymbosum) and rabbiteye (RB) (V. virgatum) blueberries were analyzed under a scanning electron microscope (SEM) to observe microstructural differences in their skin. Rabbiteye blueberries of both frozen, thawed and osmotically-dehydrated treatments, had thicker skins than highbush blueberries. Rabbiteye blueberries, collected from local farms, packed and blast frozen (PBF), had thinner skins than individually quick-frozen (IQF) blueberries. Washing berries prior to freezing had no effect on skin thickness. Sensory analysis of samples determined there were no differences (p > 0.05) between PBF and IQF methods and species with respect to skin intactness, grittiness, sweetness, and …


Molecular Basis Of Viroid Rna-Templated Transcription, Shachinthaka D. Dissanayaka Mudiyanselage Dec 2022

Molecular Basis Of Viroid Rna-Templated Transcription, Shachinthaka D. Dissanayaka Mudiyanselage

Theses and Dissertations

Transcription is a fundamental process catalyzed by DNA-dependent RNA polymerases (DdRPs). Interestingly, some DdRPs can use both DNA and RNA as templates for transcription. This RNA-dependent RNA polymerase (RdRP) activity of DdRPs is used by RNA-based pathogens such as viroids and hepatitis delta virus for replication. In addition, RdRP activity of DdRPs widely occurs in various organisms to regulate gene transcription. Despite the importance of this intrinsic RdRP activity of DdRPs, associated factors and mechanisms are in their infancy stage. We employed potato spindle tuber viroid (PSTVd) as a model to study RNA-templated transcription. Here, we present evidence showing that …