Life Sciences Commons^™

Surface Levels, Keisha Brathwaite

Electronic Theses and Dissertations

Surface Levels are depictions of unobserved and imperceptible realities of many phytoplankton exteriors. The exhibition explores various structures, textures, and repetitious forms from microscopic surfaces of objects that cannot be seen with unaided eyes. Electron microscopy is used to perceive and analyze these otherwise unseeable surfaces in depth. Magnifications provide a reference in creating three- and two-dimensional works that are minimalistic and abstract at a visible level. This abstract 3D/2D image collection is translated into material expressions using acrylic sheets, acrylic ink, and wood as the main media for construction of individual works. Collectively, they serve to make the invisible …

The Relationship Between Cell-Free Dna And Resistance Training, Henry Lang

Electronic Theses and Dissertations

The primary purposes of this dissertation were to explore relationship between cell free DNA (cf-DNA), creatine kinase (CK), C-reactive protein (CRP), vertical jump testing delayed onset muscle soreness (DOMS) in response to a high-volume resistance training protocol, and to assess the sensitivity of cf-DNA to different resistance training volume loads. The secondary purpose was to examine the relationship between cf-DNA and relative strength. Study 1 was an exploratory attempt to discover relationships between cf-DNA, CK, CRP, delayed onset muscle soreness, and performance variables. Seventeen resistance trained males were recruited, 9 were randomly assigned to receive BCAAs while 8 received a …

Comparative Secretomics And Functional Analysis Of Effectors Utilized By The Microbotryum Genus Of Anther-Smut Fungal Pathogens, And Their Role In Host-Specificity., William Christopher Beckerson

Electronic Theses and Dissertations

Understanding how pathogens evolve in response to changes in their host is paramount to combating the spread of emergent strains of disease. This is particularly true for plant pathogens that cause billions of dollars of damages to crops globally, every year. Understanding the molecular interactions between pathogens and their hosts therefore sheds light on the coevolutionary arms race that can result in host-specificity and host-shifts in plant pathogens. This research approaches the question of how fungal pathogens interact with their plant hosts utilizing both unique and shared arsenals of secreted proteins (SPs) during infection, and addresses the question of whether …

Tissue-Resident Myeloid-Derived Suppressor Cells Modulate Immune Homeostasis In Healthy Adipose., Katlin Brooke Stivers

Electronic Theses and Dissertations

Our goal with this study was to gain insight into the homeostatic immune cell network in healthy adipose tissue. Specifically, we sought to determine if the immature myeloid cells found in healthy and inflamed adipose were, in fact, tissue-resident myeloid-derived suppressor cells (MDSCs). Using various in vitro and in vivo methods, we have uncovered a population of CD11b^Hi Ly6C^Hi Ly6G^- MDSCs resident in healthy adipose tissue. To the best of our knowledge this is the first time that these cells have been investigated and described in healthy adipose tissue. Systemic MDSC depletion lead to the accumulation of …

A Novel Role For Rassf1a In The Regulation Of Ras Activation., Desmond Ramón Harrell Stewart

Electronic Theses and Dissertations

Ras is the most frequently activated oncogene in human cancer. It is not only the most frequently mutated oncogene, but is also rendered hyperactive in the wild-type form by aberrant regulation. Ras drives transformation and contributes to tumor aggressiveness by activating multiple downstream mitogenic effectors. Ras also possesses the paradoxical ability to induce apoptosis and senescence. Ras-induced apoptosis is not well understood, but has been largely attributed to the RASSF tumor suppressors, particularly RASSF1A. RASSF1A mediates Ras-induced apoptosis by activating pro-apoptotic proteins such as the MST kinases and BAX. RASSF1A is among the most frequently inactivated tumor suppressors in human …

Analyzing The Management Practices Of East Texas Beef Cattle Producers, Hiliary Cheyenne Swor

Electronic Theses and Dissertations

A survey of East Texas beef cattle producers was designed to evaluate the management practices that were prevalent in the area. Demographic and cattle operation data from 103 respondents were analyzed using SPSS (Version 25; Chicago, IL). This electronic-based survey was distributed through Qualtrics. Respondents were located in Angelina, Nacogdoches, or Cherokee county. Most producers (38.8%) had a Bachelor’s degree. A negative correlation was established between castration method and weaning weight (p = - 0.204). Calves were weaned 50 pounds heavier when band or surgically castrated. Females were less likely to castrate their calves or utilize a mineral program. Approximately, …

Costs And Benefits Of Hipv-Mediated Eavesdropping Under Field Conditions., Grace Ellin Freundlich

Electronic Theses and Dissertations

Eavesdropping is defined as the act of an organism taking advantage of a cue that was not originally intended for them for their own gain. Plant-mediated eavesdropping is a widely documented phenomenon and eavesdropping cues range from oviposition cues to airborne volatile compounds. Eavesdropping is predicted to be widespread because eavesdropping confers a fitness advantage. In plants, eavesdropping on herbivore-induced plant volatiles (HIPVs) often results in enhanced resistance profiles upon herbivory. As a result of this enhanced resistance, it is predicted that eavesdropping alone incurs minor costs due to resource shifts towards inducible defense responses. Although HIPV-mediated eavesdropping is widely …

N-Acetyltranserase 2 (Nat2) Genotype Polymorphism In Cryopreserved Human Hepatocytes And Chinese Hamster Ovary (Cho) Cells., Mariam Refaat Zaky Habil

Electronic Theses and Dissertations

Arylamine N-acetyltransferases, NAT1 and NAT2, catalyze the detoxification and/or activation of drugs and aromatic amine carcinogens. Single nucleotide polymorphisms or SNPs result in different human NAT2 genotypes thus dividing the population into rapid, intermediate, and slow acetylators. We hypothesize allelic variants of NAT2 genotype will decrease levels of N-acetylation, cytotoxicity, oxidative stress, DNA adduct formation, and mutagenesis compared to the reference allele NAT2*4. Cryopreserved human hepatocytes expressing different NAT2 genotypes and NER-deficient Chinese hamster ovary (CHO) cells transfected with human CYP1A2 and human NAT2*4, NAT2*5B or NAT2*7B have been used to investigate N-acetylation of different xenobiotics. In …

Genes Involved In Nitrogen Assimilation In Ustilago Maydis., Sunita Khanal

Electronic Theses and Dissertations

U. maydis can utilize nitrate as a source of nitrogen from its environment, a process requiring a nitrate transporter to bring the nitrate inside the cell. This is followed by a two-step reduction of nitrate to ammonium. At first, nitrate reductase reduces nitrate into nitrite; in the second reaction, nitrite is reduced to ammonium by nitrite reductase. The goal of the study was to identify the nitrate transporter and nitrite reductase genes in U. maydis and characterize them based on their role in mating and virulence. The genes um03848 and um03849 were identified bioinformatically as encoding, respectively, the nitrite reductase …

Plasmodium Impairs Antibacterial Innate Immunity To Systemic Infections In Part Through Hemozoin-Bound Bioactive Molecules., Christopher Lynn Harding

Electronic Theses and Dissertations

Despite efforts to decrease the global health burden of malaria, infections with Plasmodium species continue to cause over 200 million episodes of malaria each year which resulted in 405,000 deaths in 2018 [1]. One complication of malaria is increased susceptibility to invasive bacterial infections. Plasmodium infections impair host immunity to non-Typhoid Salmonella (NTS) through activities of heme oxygenase I (HO-I) )-induced release of immature granulocytes and myeloid cell-derived IL-10. Yet, it is not known if these mechanisms are specific to NTS. We show here, that Plasmodium yoelii 17XNL (Py) infected mice had impaired clearance of systemic Listeria monocytogenes (Lm) during …

Identification And Structural Characterization Functional Motifs In The Porphyromonas Gingivalis Mfa1 Short Fimbria., Mohammad K. Roky

Electronic Theses and Dissertations

Porphyromonas gingivalis is a causative agent of periodontal disease, initially colonizes the oral cavity by adhering to commensal streptococci. Adherence requires the interaction of the minor fimbrial protein (Mfa1) of P. gingivalis with streptococcal antigen I/II (Ag I/II). A peptide derived from Ag I/II peptide has been well characterized and shown to significantly reduce P. gingivalis colonization and bone loss in vivo, suggesting that this interaction represents a potential target for therapeutic intervention. However, the functional motifs of Mfa1 involved in the interaction with Ag I/II remain uncharacterized. A series of N- and C-terminal peptide fragments of Mfa1 were …

An Eeg Study On Loneliness And Recognition Memory, Carmen Jia Wen Chek

Electronic Theses and Dissertations

Loneliness, the perception of unmet social needs, has been shown to relate to recollection-based recognition deficits, but the relationship between loneliness and recognition memory (i.e., recollection and familiarity) has not been thoroughly examined. The current study hypothesized that more lonely individuals would have lower recognition memory performance, specifically recollection, with smaller ERP parietal old-new effects than less lonely individuals. Forty participants, grouped into less (n = 13) and more (n = 9) lonely groups based on their R-UCLA responses, completed an associative memory task. EEG was used to assess recognition memory effects. Results showed no significant difference in …

Simulated Mine Land Reclamation Impact On Biomass Partitioning And Nutrient Contents In Loblolly Pine, Osarumen Egharevba

Electronic Theses and Dissertations

Forest productivity on reclaimed mine land is hindered by soil compaction. Different techniques have been used to alleviate the effect of compaction to various degrees of success. The Forestry Reclamation Approach (FRA) was developed in the Appalachians and has been used to improve forest productivity on reclaimed mines in this region. The FRA provides a step by step method designed to reduce compaction, control erosion, provide land stabilization and accelerate forest succession. This method had not been evaluated in the Gulf Coastal Plain, where the pan scraper reclamation method is commonly used. However, using pan scrapers increases mine soil compaction …

Development Of A Pharmaceutical Tablet Authentication System Using Spectroscopic Techniques In Combination With Multivariate Chemometric Methods, Md Nayeem Hossain

Electronic Theses and Dissertations

The spread of falsified drugs is increasing worldwide. Currently, 10%-30% of drugs in the world are falsified. Unfortunately, the supply chain system of developing countries (from manufacturers to customers) is not well monitored and suffers the highest rates of fraudulent activities. Also, the rise of product procurement from the internet increases the chance of American consumers' exposure to poor quality drugs. To combat this horrendous activity, surveillance of pharmaceutical materials is required in the supply chain system. Spectroscopic techniques (e.g., Near-Infrared and Raman spectroscopies) can be a potential solution to authenticate samples in different locations; they are non-destructive, safe, rapid, …

The Effects Of Different Amino Acid Concentrations, With Or Without Chromium Supplementation, On The Performance And Yield Of Commercial Broiler Chickens Fed Two Different Feeding Programs., Ian Brock

Electronic Theses and Dissertations

Abstract

The objective of this study was to evaluate performance parameters and meat yield of commercial broiler chickens fed diets with different amino acid concentrations, with or without chromium supplementation, and delivered through two different feeding programs over 54 days. The experimental study was completed as a randomized-block design with 4,800, Ross 708 X Ross 708 commercial broiler chickens, picked at random, and evenly divided into six treatment groups (800 birds per group). Treatments 1 and 4 where placed under feeding program (FP1). Treatments 2, 3, 5, and 6 where placed under a different feeding program (FP2). Three different feed …

Testing The Potential Of Environmental Dna: Genetic Monitoring Of Estuarine And Coastal Bottlenose Dolphin (Tursiops Truncatus) Stocks In South Carolina, Kathryn Greiner-Ferris

Electronic Theses and Dissertations

Environmental DNA (eDNA) analysis is a non-invasive monitoring technique that can detect and potentially monitor elusive marine mammals. To date, the majority of eDNA studies have been performed in freshwater environments, partially due to methodological challenges posed by higher salinities and increased dilution effects of large water masses in marine environments. The objective of this study was to design and optimize species-specific oligonucleotide PCR primers to accurately detect and quantify common bottlenose dolphin (Tursiops truncatus) eDNA collected from the marine environment and to evaluate potential trends between eDNA concentration and dolphin abundance and seasonality. Primer pairs were designed to target …

Pilot Study Exploring The Effect Of Targeted Cox-2 Inhibition In Macrophages Responding To Neuronal Injury; Promoting Enhanced Axonal Regeneration, Alyssa Brauckmann

Electronic Theses and Dissertations

Celecoxib nanoemulsion (CXB-NE) has been developed as a macrophage targeted analgesics by Dr. Janjic and her team at Duquesne University, (Janjic et al, 2018; Liu et al, 2020; Saleem et al, 2019b; Vasudeva et al, 2014). The CXB-NE nanoemulsion carrying a Nonsteroidal Anti-inflammatory (NSAID) inhibitor of COX-2 activity result in a reduction in PGE2 expression in macrophages. Using CXB-NE in rats that have peripheral nerve injury constricting the sciatic nerve relieves hypersensitivity, a pain-like behavior. The treatment also decreases inflammation associated with this chronic constriction injury (Janjic et al, 2018; Saleem et al, 2019b; Stevens et al, 2019). In this …

The Physiology And Evolution Of Selenite Respiration In Bacteria, Michael Wells

Electronic Theses and Dissertations

The selenium oxyanions selenate (Se(VI)) and selenite (Se(IV)) can be utilized by some bacteria and archaea as terminal electron acceptors in anaerobic respiration. Se(VI) and Se(IV) respiration is mediated by a phylogenetically and ecologically diverse array of organisms, suggesting that selenium respiration is ubiquitous in natural environments. Several respiratory Se(VI) reductases have been characterized in bacteria, revealing that Se(VI) respiration has evolved independently several times in this domain. Se(IV) respiration, in contrast, has yet to be characterized. I have purified and characterized the first respiratory Se(IV) reductase from Bacillus selenitireducens MLS10. The Se(IV) reductase appeared to purify as a single …

A Genomic Analysis Of Bobcat Populations In North America With A Comparison To The Canada Lynx: An Assessment Of Local Adaptation To Unique Ecoregions And Phylogeography, Jennifer C. Broderick

Electronic Theses and Dissertations

Bobcats (Lynx rufus) are an ecologically and genetically diverse species with a large contiguous range throughout North America. The species not only has a wide array of phenotypic variation compared to other mammals, but shows marked adaptability across ecozones with differing ecological influences. It is these various selective pressures in distinctive parts of the continent that have likely led to localized adaptations within the bobcat metapopulations. The species is also marked by its ability to maintain connectivity and populations in anthropogenically developed areas, an advantage it has over other felids, including its close relative the Canada lynx ( …

Effects Of Warming On Decomposition Of Submerged Plant Litter And Associated Microorganisms In Streamside Channels, Kaity Ackerman

Electronic Theses and Dissertations

Surface air temperatures are predicted to increase in the near future, which will likely affect microbial activity and carbon flow in stream ecosystems. I performed an experiment in streamside channels at Coweeta Hydrological Laboratory, NC to assess responses of litter-associated microorganisms to moderate increases in water temperature (5 levels, ambient to +4°C). The objectives of the experiment were to determine: (1) if there are differences in the magnitude of responses to temperature among various microbial parameters and (2) whether microbial responses to temperature vary among plant litter of different carbon quality. Thus, I measured litter decomposition rate, fungal biomass (ergosterol), …

Modulation Of Host Innate Immune Cells By Yersinia Pestis To Create A Permissive Environment For Replication., Amanda Rose Pulsifer

Electronic Theses and Dissertations

Yersinia pestis has gained widespread infamy due to the historic outbreak during the middle ages, referred to as The Black Death. Infection with Y. pestis typically begins with deposition of Y. pestis into the dermis (bubonic plague) or respiratory tract (pneumonic plague). Tissue resident macrophages are the first innate immune cell encountered by Y. pestis. Macrophages are likely a way for Y. pestis to avoid neutrophils early in infection when the neutrophil neutralizing Type Three Secretion System is not expressed. This work focuses on which Rab host proteins are manipulated by Y. pestis, and how neutrophils are forced to …

Formation, Organization, And Synaptic Properties Of Circuits Between Thalamic Reticular Nucleus And Dorsal Lateral Geniculate Nucleus., Peter W. Campbell

Electronic Theses and Dissertations

The thalamic reticular nucleus (TRN) is an interface between thalamus and cortex that regulates thalamocortical rhythms and modulates sensory processing. Thalamocortical axon collaterals provide feedforward excitatory input onto GABAergic TRN neurons, which in turn convey feedback inhibition to dorsal thalamus. Here we used the mouse visual system to study the organization, pattern of innervation and functional responses between TRN and the dorsal lateral geniculate nucleus (dLGN). We used genetically modified mice to target components of this feedback loop (feedforward: CRH-Cre; feedback: GAD65 or SST-Cre) and we created Math 5^-/- strains to examine the impact of visual deaffrentation in these …

The Role Of Slc7a11 In Controlling Extracellular And Intracellular Redox Environments Of Lung Fibroblasts - Potential Targets For Intervention In Aging And Idiopathic Pulmonary Fibrosis., Yuxuan Zheng

Electronic Theses and Dissertations

Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease characterized by extracellular matrix deposition by fibroblasts. Aging and oxidative stress increase the susceptibility to IPF. Redox couples, cysteine/cystine (Cys/CySS) and glutathione/glutathione disulfide (GSH/GSSG), and their redox potentials (E_h) quantify oxidative stress. Fibroblasts from old mice maintain more oxidized extracellular E_h(Cys/CySS) than young mice. Microarray shows down-regulation of Slc7a11 potentially mediates this age-related oxidation. Slc7a11 is the key component of system X_c^-, an antiporter that imports CySS and exports glutamate. The first aim of this dissertation is to investigate the mechanistic link between Slc7a11 …

Alcohol Consumption In A Preclinical Model Of Schizophrenia, Liza Hernandez

Electronic Theses and Dissertations

Schizophrenia is a debilitating psychiatric disorder that affects approximately 1% of the global population. Schizophrenia is highly comorbid with other psychiatric disorders such as Alcohol Use Disorder (AUD) with a prevalence rate of 27% - 65%, which is significantly higher than AUD exhibited by the general population (6%). Research indicates that a higher rate of AUD in individuals suffering from schizophrenia may be related to the common neuronal pathways that underlie the expression of both disorders. The present study will determine whether the neonatal quinpirole (NQ) rodent model of schizophrenia will approximate the human condition and exhibit increased EtOH consumption. …

Chronoecology Of A Cave-Dwelling Orb-Weaver Spider, Meta Ovalis (Araneae: Tetragnathidae), Rebecca Steele

Electronic Theses and Dissertations

Circadian clocks enable coordination of essential biological and metabolic processes in relation to the 24-hour light cycle. However, there are many habitats that are not subject to this light cycle, such as the deep sea, arctic regions, and cave systems. This study analyzes the circadian pattern of isolated populations of a subterranean spider, Meta ovalis from two Tennessee caves and five Indiana caves. Locomotor activity was recorded with TriKinetics LAM50 Locomotor Activity Monitor under a 12-hour light (L), 12-hour dark (D) (LD 12:12) cycle preceding total darkness (DD). Significant differences were found within and among populations found in Tennessee cave …

Encephalization In Commensal Raccoons: A Unique Test Of The Cognitive Buffer Hypothesis, Peter M. Anderson

Electronic Theses and Dissertations

This study investigated selective pressures associated with encephalization in mammals and discussed broader implications. Relative brain size as measured by EQ (Encephalization Quotient) was compared between ecological categories. Omnivores had higher average EQ than ecological specialists. Since specialists are disproportionately affected by extinction events, selection for ecological generalism is proposed as encephalization mechanism. This mechanism may reinforce the more widely known Cognitive Buffer Hypothesis (CBH)—the idea that possessing relatively large brains has buffered lineages against environmental change. CBH is tested here by comparing EQs in Procyon lotor (raccoon) in urban and rural environments. CBH predicts that raccoons in the most …

Understanding The Implications Of Anandamide, An Endocannabinoid In An Early Land Plant, Physcomitrella Patens, Md Imdadul Haq

Electronic Theses and Dissertations

Endocannabinoid signaling is well studied in mammals and known to be involved in numerous pathological and physiological processes. Fatty acid amide hydrolase (FAAH) terminates endocannabinoid signaling in mammals. In Physcomitrella patens, we identified nine orthologs of FAAH (PpFAAH1 to PpFAAH9) with the characteristic catalytic triad and amidase signature sequence. Kinetics of PpFAAH1 showed specificity towards anandamide (AEA) at 37°C and pH 8.0. Further biophysical and bioinformatic analyses revealed that, structurally, PpFAAH1 to PpFAAH4 were closely associated to the plant FAAH whereas PpFAAH6 to PpFAAH9 were more closely associated to the animal FAAH. A substrate entry gate or ‘dynamic paddle’ …

A Novel Mode Of Action Of C-Reactive Protein In Protecting Against Streptococcus Pneumoniae Infection And Synergy With Antibiotics, Donald Ngwa

Electronic Theses and Dissertations

C-reactive protein (CRP) is a part of the innate immune system, is synthesized in the liver, its blood level increases in inflammatory states, and it binds to Streptococcus pneumoniae. The conformation of CRP is altered under conditions mimicking an inflammatory milieu and this non-native CRP also binds to immobilized/aggregated/pathogenic proteins. Experiments in mice have revealed that one of the functions of CRP is to protect against pneumococcal infection. For protection, CRP must be injected into mice within two hours of administering pneumococci, thus, CRP is protective against early-stage infection but not against late-stage infection. It is unknown how CRP protects …

Protection Against Atherosclerosis By A Non-Native Pentameric Crp That Shares Its Ligand Recognition Functions With An Evolutionarily Distant Crp, Asmita Pathak

Electronic Theses and Dissertations

C-reactive protein (CRP) is an acute phase protein of the innate immune system that has been evolutionarily conserved. Human CRP is known to exist in two different pentameric conformations; native CRP and non-native CRP that possess differential ligand recognition functions. The structure of CRP evolved from arthropods to humans, in terms of subunit composition, disulfide bonds, and glycosylation pattern. Along with change in structure, the gene expression pattern of CRP also evolved from a constitutive protein in lower invertebrates to an acute phase protein in humans. The objective of this study was to determine the function of a non-native pentameric …

Ontogenetic And Adult Shape Variation In The Endocast Of Tapirus: Implications For T. Polkensis From The Gray Fossil Site, Thomas M. Gaetano

Electronic Theses and Dissertations

Endocranial morphology provides evidence of sensory ecology and sociality of extinct vertebrates. The Earliest Pliocene Gray Fossil Site (GFS) of NE Tennessee features a conspicuous dominance of skeletal elements belonging to the dwarf tapir, Tapirus polkensis. Numerous individuals in one fossil locality often suggests gregarious behavior, but sociality in T. polkensis contradicts behavior documented for extant Tapirus species. I test T. polkensis for variation in sensory and social ecology using computed tomography and 3D digital endocasts from an ontogenetic sequence. I compare the T. polkensis endocasts with extant Tapirus species using Encephalization Quotients (EQs) and 3D geometric morphometrics. Results …