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Full-Text Articles in Life Sciences

The Effect Of Gut Microbiota On Overwintering Success In Mule Deer, Emma Wilcox Dec 2022

The Effect Of Gut Microbiota On Overwintering Success In Mule Deer, Emma Wilcox

Theses and Dissertations

Mule deer are an important rangeland grazer, large prey species, and game animal for the state of Utah, so herd size is monitored and managed actively. A significant cause of population decline is poor overwintering survival, including from the lack of available forage during winter months. Mule deer energy storage is correlated with greater overwintering success, so physical estimates of energy storage including body condition score (BCS), rump fat (RF), and loin thickness (LT), can be used to track and predict a herd's health. Current methods of collecting deer information are costly, time consuming, and cause physical stress to deer, …


Biofilm Characterization And The Potential Role Of Edna In Horizontal Gene Transfer In Hospital And Meat Isolates Of Staphylococcus Aureus And Their Biofilms, Ashley Lynne Ball Dec 2022

Biofilm Characterization And The Potential Role Of Edna In Horizontal Gene Transfer In Hospital And Meat Isolates Of Staphylococcus Aureus And Their Biofilms, Ashley Lynne Ball

Theses and Dissertations

Staphylococcus aureus is a pathogen responsible for a wide variety of life-threatening diseases such as bacteremia, endocarditis, and pneumoniae. S. aureus has been a major concern in recent years due to the rampant spread of antibiotic resistance. The ability of S. aureus to form biofilms aids in the spread of antibiotic resistance as biofilms are a known hotspot for horizontal gene transfer. Biofilms also protect cells from host immune responses and antibiotics, making these infections very difficult to treat. The matrix of S. aureus biofilms can be made of polysaccharides, protein, and DNA. In these studies, we sought to elucidate …


The Role Of Chitinase A In Mastitis-Associated Escherichia Coli Pathogenesis, Weston D. Hutchison Dec 2022

The Role Of Chitinase A In Mastitis-Associated Escherichia Coli Pathogenesis, Weston D. Hutchison

Theses and Dissertations

Bovine mastitis is a common disease among dairy cattle characterized by the inflammation of the udders and loss of milk production. Mastitis-associated Escherichia coli (MAEC) are frequent causes of the disease, but the features that distinguish them from other E. coli strains remain enigmatic. MAEC infections can range from sub-clinical to severe, acute cases that can be fatal. Historically, the severity of mastitis has been attributed to host factors but more recently, a few bacterial genes have been shown to contribute to virulence in mastitis infections. In a large-scale genomic analysis of >100 MAEC isolates the gene for Chitinase A …


Does Predation Environment Affect Repeated Responses To Predation Cuesâ In The Fishâ Brachyrhaphis Rhabdophora?, Madeleine S. Nate Dec 2022

Does Predation Environment Affect Repeated Responses To Predation Cuesâ In The Fishâ Brachyrhaphis Rhabdophora?, Madeleine S. Nate

Theses and Dissertations

Individual organisms face trade-offs when dealing with predation—more time spent avoiding predators often results in less time allocated to energy acquisition and reproductive-related activities. Individuals that optimize this trade-off and respond appropriately to current risk levels in their environment should be at an advantage. What is less clear is whether this tradeoff changes when individuals are repeatedly exposed to a predation threat. There may be advantages to responding consistently to every signal of threat, but it might also be advantageous to modulate individual behavior. Moreover, it is unclear how evolutionary history of a population might affect such individual responses. Our …


Quantifying Shape Variation In An Antisymmetrical Trait In Xenophallus Umbratilis, Mary-Elise Johnson Nielsen Dec 2022

Quantifying Shape Variation In An Antisymmetrical Trait In Xenophallus Umbratilis, Mary-Elise Johnson Nielsen

Theses and Dissertations

Antisymmetry is a striking, yet puzzling form of biological asymmetry. The livebearing fish Xenophallus umbratilis exhibits antisymmetry in the male intromittent organ and provides a system that is well-suited for studying the nature of variation in antisymmetrical traits. Using geometric morphometrics, I test the hypothesis that because the gonopodium is critical to fitness there will not be significant differences in gonopodium shape between the two gonopodial morphs in this species. My results are consistent with this prediction, though I found that gonopodium shape did differ with gonopodium size.


Novel Patterns For Nucleosome Positioning: From In Vitro To In Vivo, David Andrew Bates Dec 2022

Novel Patterns For Nucleosome Positioning: From In Vitro To In Vivo, David Andrew Bates

Theses and Dissertations

The fundamental unit of chromatin is the nucleosome, which consists of a core of eight proteins wrapped by DNA. This core is composed of four pairs of histone proteins: H2A, H2B, H3, and H4. The DNA wraps around the protein core ~1.7 times, facilitating compaction of DNA length in the cell. Further, the location of nucleosomes makes genomic elements encoded in the DNA, such as promoters or enhancers, accessible or inaccessible to RNA polymerase and transcription factors. Thus, where nucleosomes are located (or positioned), can play a major role in transcription or other cellular processes. Additionally, histone proteins are frequently …


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 …


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 …


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 …


Unraveling The Anti-Inflammatory Mechanisms And Efficacy Of Cannabidiol On The Progression Of A Murine Model Of Multiple Sclerosis From The Innate To The Adaptive Immune System To Clinical Symptoms, Christa Marie Frodella Dec 2022

Unraveling The Anti-Inflammatory Mechanisms And Efficacy Of Cannabidiol On The Progression Of A Murine Model Of Multiple Sclerosis From The Innate To The Adaptive Immune System To Clinical Symptoms, Christa Marie Frodella

Theses and Dissertations

Cannabidiol (CBD), a non-psychotropic phytocannabinoid with structural similarity to Δ 9 -tetrahydrocannabinol (THC), is currently being investigated as a therapeutic for its immunosuppressive effects. One disease for which CBD is extensively researched is multiple sclerosis (MS), a demyelinating, autoimmune disorder, and its murine model counterpart, experimental autoimmune encephalomyelitis (EAE). The focus of this dissertation aimed to analyze the transcriptomic brain pathways in EAE and its comparison to MS in addition to CBD’s immunosuppressive mechanisms in the innate and adaptive immune systems. Evidence presented here showed that transcriptomic signaling pathways in the EAE brain of mice with clinical symptoms were similar …


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 …


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 …


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 …


Molecular And Phenotypic Characterization Of Escherichia Coli Isolated From Broiler Chicken Flocks In Mississippi, Priyanka Devkota Dec 2022

Molecular And Phenotypic Characterization Of Escherichia Coli Isolated From Broiler Chicken Flocks In Mississippi, Priyanka Devkota

Theses and Dissertations

Avian pathogenic Escherichia coli (APEC) is the causative agent of colibacillosis. APEC causes significant economic losses to the poultry industry. In this study, 66 E. coli isolates were collected from broiler flocks across Mississippi and categorized as clinical and non-clinical isolates. Genotypic and phenotypic characterization of virulence factors and antimicrobial resistance profiles of these E. coli were examined. The data disclosed a higher prevalence of virulence genes in clinical isolates than in non-clinical isolates. High differences on the genotypic and phenotypic antimicrobial resistance among clinical and non-clinical isolates were observed. Whole genome sequences of avian E. coli elaborated a diverse …


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 …


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 …


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 …


Evaluation Of Warm Season Vegetables Using Sustainable Production Practices, Jacob Arthur Dec 2022

Evaluation Of Warm Season Vegetables Using Sustainable Production Practices, Jacob Arthur

Theses and Dissertations

Sustainable practices were evaluated for the production of two warm season vegetable crops, tomato and chile peppers. The first study investigated the plant vegetative growth, fruit production timing, yield components and fruit quality of three hybrid and three heirloom tomato cultivars grown in a high tunnel using grafted and non-grafted plants. Grafting the selected tomato cultivars with the two rootstock types did not alter total marketable yield of any cultivar, but affected overall stem diameter, fruit color, and β-carotene concentrations of tested tomato cultivars. The second study evaluated the plant growth, yield, and fruit quality of nine heirloom chile pepper …


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 …


Survival, Regrowth And Morphotype Formation Of Salmonella Strains After Exposure To High Or Low Concentrations Of First Generation Qac In Water, Grace Umutesi Dec 2022

Survival, Regrowth And Morphotype Formation Of Salmonella Strains After Exposure To High Or Low Concentrations Of First Generation Qac In Water, Grace Umutesi

Theses and Dissertations

This study determines the differences in survival of eight Salmonella strains concentration of BAC in water, followed by regrowth in high and low nutrition conditions containing sublethal concentration of BAC. Our results show strain difference in survival, persistence of Salmonella in BAC at different concentrations. All eight strains of Salmonella were non-recoverable when exposed to 40 to 48 µg/ml BAC for 1h in water. When exposed to 24 µg/ml of BAC for 1 h in water, S. Typhimurium ATCC 14028 and S. Heidelberg ATCC 8326 cells were non-detectable from the initial 7 log CFU/ml. S. Blockley 7175, S. Virchow 7207, …


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 …


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 …


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 …


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 …


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 …


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 …


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 …


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 …