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Impact Of Lyophilization On Porcine Hemoglobin Properties., Mustafa Almosawi May 2023

Impact Of Lyophilization On Porcine Hemoglobin Properties., Mustafa Almosawi

College of Arts & Sciences Senior Theses

Blood transfusion is the single most often performed lifesaving procedure in hospitals worldwide. Unfortunately, packed red blood cells (RBCs) used for transfusion can only be stored for 42 days at 4 °C before being discarded due to irreversible damage that occurs during storage. Any reduction in available RBCs for an extended period can lead to blood shortages. To increase the shelf-life of RBCs, we investigated freeze-drying (lyophilizing) in the presence of the non-toxic sugar trehalose as a method for long-term preservation. However, the oxidative stress of the lyophilization and storage processes can compromise the functionality of these cells, and the …


A Field‐Capable Rapid Plant Dna Extraction Protocol Using Microneedle Patches For Botanical Surveying And Monitoring, Jonathan Selz, Nicolas R. Adam, Céline E. M. Magrini, Fulvia Malvido Montandon, Sven Buerki, Sebastian J. Maerkl May 2023

A Field‐Capable Rapid Plant Dna Extraction Protocol Using Microneedle Patches For Botanical Surveying And Monitoring, Jonathan Selz, Nicolas R. Adam, Céline E. M. Magrini, Fulvia Malvido Montandon, Sven Buerki, Sebastian J. Maerkl

Biology Faculty Publications and Presentations

Premise: A novel protocol for rapid plant DNA extraction using microneedles is proposed, which supports botanic surveys, taxonomy, and systematics. This protocol can be conducted in the field with limited laboratory skills and equipment. The protocol is validated by sequencing and comparing the results with QIAGEN spin-column DNA extractions using BLAST analyses.

Methods and Results: Two sets of DNA extractions were conducted on 13 species spanning various leaf anatomies and phylogenetic lineages: (i) fresh leaves were punched with custom polymeric microneedle patches to recover genomic DNA, or (ii) QIAGEN DNA extractions. Three plastid (matK, rbcL, and trnH-psbA …


Use Of Space And Foraging Behavior Of Loggerhead Shrikes In Urban Areas, Katie Anne Maddox May 2023

Use Of Space And Foraging Behavior Of Loggerhead Shrikes In Urban Areas, Katie Anne Maddox

Electronic Theses and Dissertations

Loggerhead shrikes, Lanius ludovicianus, are a declining grassland songbird native to North America. Land-use change has been associated with the decline of grassland bird species. However, the process of urbanization creates novel short-grass habitats reminiscent of shrikes’ natural habitats. Loggerhead shrikes have been observed living in developed areas, particularly in Southeastern coastal states. Understanding the long-term impacts of urban-dwelling on loggerhead shrike populations is vital to identifying whether urban areas offer refuge or act as an ecological sink for shrike populations.

In chapter one, I quantified the use of space by shrikes in urban habitats within Horry County, South …


Deterrent Effects Of The Select Magnetic And Repellent Treated (Smarttm) Hooks And The Recently Developed "Smarter" Hooks On Sharks In Recreational Hook-And-Line And Longline Trials, Ryan Lowndes May 2023

Deterrent Effects Of The Select Magnetic And Repellent Treated (Smarttm) Hooks And The Recently Developed "Smarter" Hooks On Sharks In Recreational Hook-And-Line And Longline Trials, Ryan Lowndes

Electronic Theses and Dissertations

As bycatch continues to impact global shark populations, there is a continuing need for effective bycatch reduction devices. Prior research has shown promise in exploiting sharks' electrosensory ability to this end. We tested the deterrent efficacy of the Select Magnetic and Repellant Treated (SMARTTM) and the newly developed "SMARTER" hooks in experimental longline and hook-and-line trials. Both are magnetized and contain an electropositive metal component made of magnesium (SMART) and a magnesium alloy designed to extend longevity (SMARTER). We deployed 127 longlines with SMART hooks, SMARTER hooks, controls, and procedural controls from 2021-2022 in Winyah Bay, South Carolina, and caught …


Importance Of Pelvic Floor Education And Rehabilitation Techniques For Adolescents And Young Adults: A Review, Katherine Laura Schmidt May 2023

Importance Of Pelvic Floor Education And Rehabilitation Techniques For Adolescents And Young Adults: A Review, Katherine Laura Schmidt

Honors Program: Senior Projects (Public)

The pelvic floor is the collection of many muscles forming what is often called the pelvic girdle. Understanding the different muscles and their roles is an important part of pelvic floor education. Although both males and females have pelvic floors, there is a lack of knowledge of basic anatomy seen in adolescents and young adults. This review analyzes the importance of providing more education for students about the pelvic floor, gives examples of common pelvic disorders for young adults, and provides details on the physical therapy rehabilitation techniques offered today to treat these conditions.


Extranodal Tumors And Chromosomal Abnormalities Associated With Non-Hodgkin Lymphoma In T(14;18)-Positive Patients, Alexis Finch May 2023

Extranodal Tumors And Chromosomal Abnormalities Associated With Non-Hodgkin Lymphoma In T(14;18)-Positive Patients, Alexis Finch

Honors Program: Senior Projects (Public)

Nebraska is mostly an agricultural state with a non-Hodgkin lymphoma (NHL) incidence rate of 20.1 per 100,000 individuals, which is greater than the US incidence rate of 19 per 100,000 individuals. It is possible that the higher incidence rate in Nebraska is due to an increase in pesticide usage. Pesticide exposure is linked to t(14;18), a genetic translocation involving the BCL2 gene that regulates apoptosis. The dysregulation of apoptosis could contribute to the proliferation of NHL. This exploratory study utilized the Nebraska Lymphoma Study Group, which consists of patients with non-Hodgkin lymphoma, Hodgkin disease, or some other neoplastic hematologic disorder …


Education, Beliefs, And Health Literacy Of Care Providers On Mouth Care Of Older Adults, Molly Lakin May 2023

Education, Beliefs, And Health Literacy Of Care Providers On Mouth Care Of Older Adults, Molly Lakin

Honors Program: Senior Projects (Public)

Oral health is important to one’s overall health and quality of life as it can lead to chronic illnesses such as cardiovascular disease, stroke, and neurodegenerative disorders (Haumschild et al. 2021). In long-term care facilities, it is important that dependent older adults are provided mouth care to maintain their oral health and decrease their chances of developing a chronic illness; however, there are barriers affecting the level, quality, and quantity of mouth care being provided in these facilities. A survey was developed to look at the education, beliefs, and health literacy of care providers on providing mouth care in hopes …


Investigation Of The Vira Linker Domain To Characterize Its Phenol Interactions, Jessica Garofalo May 2023

Investigation Of The Vira Linker Domain To Characterize Its Phenol Interactions, Jessica Garofalo

Honors Theses

The soil bacterium Agrobacterium tumefaciens causes tumors in plants through interkingdom gene transfer. This transfer is initiated upon a wounding event that results in the release of plant signaling factors such as phenols and sugars that are recognized by protein machinery in the periplasm and inner membrane of A. tumefaciens. The histidine kinase protein VirA, in combination with the periplasmic protein ChvE, recognizes these signals and initiates induction of virulence genes via a signaling pathway, culminating with the insertion of tumor-inducing T-DNA into the wounded plant cells. While the interaction between the Periplasmic domain of VirA and sugar-bound ChvE …


Examining Transcriptional Regulators During Muscle Development In Drosophila Melanogaster, Chaamy Yapa May 2023

Examining Transcriptional Regulators During Muscle Development In Drosophila Melanogaster, Chaamy Yapa

Student Theses and Dissertations

In Drosophila melanogaster embryos, a distinct approach to study the transcriptional regulation is to examine the larval somatic muscle development. Transcription factors are essential regulatory proteins that help to control gene expression and respond to signaling pathways and various cues. Today, there are at least twenty transcription factors that have been discovered to contribute to the development of the 30 distinct larval somatic muscles in each abdominal hemisegment of Drosophila melanogaster. Several studies have already been conducted on muscle regulatory transcription factors including midline and apterous. These transcription factors were shown to control the development of muscles through mutant …


The Effects Of Glycolytic Mutations In Drosophila Melanogaster Muscle Development, Coco Lim May 2023

The Effects Of Glycolytic Mutations In Drosophila Melanogaster Muscle Development, Coco Lim

Student Theses and Dissertations

Muscle atrophy, or muscle wasting, is caused due to lack of physical activity for an extended period of time, due to muscle diseases (such as muscle dystrophies), cancer chemotherapies, and aging. It is also extensively found on astronauts after spaceflight, particularly missions of long durations. Muscle cells are dependent on different metabolic pathways to optimize Adenosine triphosphate (ATP) production to compensate for muscle exertion. Glycolysis converts glucose into ATP producing pyruvate, which can be sent into the citric acid cycle or converted to lactate (lactic acid). Muscles preferentially use lactate production, despite the fact that fewer molecules of ATP are …


Development Of A Computational Model To Investigate Pathways And The Effects Of Treatment In Fanconi Anemia, Sabrina Kellett May 2023

Development Of A Computational Model To Investigate Pathways And The Effects Of Treatment In Fanconi Anemia, Sabrina Kellett

Biological Sciences Undergraduate Honors Theses

Fanconi Anemia (FA) is a rare type of anemia that is not easily studied and can have very detrimental effects. This disease compromises the bone marrow, resulting in decreased hemopoiesis. Symptoms of FA also include abnormalities in the brain and spinal cord, incorrect formation of the kidneys, abnormal formation of the heart and lungs, and a dramatically increased risk of developing cancer. FA can be caused by various mutations in any of the 22 genes that encode for proteins involved in what is called the FA DNA repair pathway. In healthy individuals, this pathway specifically repairs interstrand cross-links (ICLs) recognized …


Sequence Analysis Of Herbicide Target Genes In Herbicide-Tolerant Rice, Jonathan Kearney, Nilda R. Burgos, Gulab D. Rangani May 2023

Sequence Analysis Of Herbicide Target Genes In Herbicide-Tolerant Rice, Jonathan Kearney, Nilda R. Burgos, Gulab D. Rangani

Biological Sciences Undergraduate Honors Theses

The tolerance of mutagenized rice (Oryza sativa) lines to selector herbicides was investigated and the sequence of ALS gene was analyzed in plants that survived treatment with 4x the label rate of imazethapyr herbicide. This was done to determine if insensitivity to imazethapyr is due to mutation(s) in the herbicide binding site. Seedlots previously treated with ethyl-methyl sulfonate were planted in the field and 3-leaf seedlings were treated with various herbicides to screen for herbicide-tolerant mutants. Seeds from survivors composed the rice lines tested in the current research. Seeds were planted in the greenhouse and 3-leaf seedlings were …


Interactive Map Code (R And Rstudio), Peter G. Butterfield May 2023

Interactive Map Code (R And Rstudio), Peter G. Butterfield

Data Files: White Oaks in Vinton Furnace Experimental Forest

Interactive map code puts data and coordinates into readable table format and creates data visualizations.


Investigation Into The Roles Of Esxa N-Α-Acetylation In Pathogenesis Of Mycobacterium Tuberculosis And Potential Host-Binding Proteins, Javier Aguilera May 2023

Investigation Into The Roles Of Esxa N-Α-Acetylation In Pathogenesis Of Mycobacterium Tuberculosis And Potential Host-Binding Proteins, Javier Aguilera

Open Access Theses & Dissertations

EsxA (6-kDa early secreted antigenic target, ESAT-6) is a critical virulence factor of Mycobacterium tuberculosis (Mtb). EsxA is secreted in a heterodimer with EsxB (10-kDa culture filtrate protein, CFP-10) through the Type VII secretion system of Mtb, called ESX-1. The dissociation of EsxA and EsxB heterodimer (EsxA:B), upon acidification, is required for EsxA to penetrate into the phagosomal membranes, which has been implicated in Mtb translocation from the phagosome to the cytosol. However, the mechanism of EsxA:B dissociation is not clear. In this study, we investigated the role of N-α-acetylation of EsxA in the heterodimer dissociation, mycobacterial cytosolic translocation, and …


Phylogenetics And Integrative Taxonomy Of African Water Snakes (Squamata: Colubridae: Grayia), Teslin Chaney May 2023

Phylogenetics And Integrative Taxonomy Of African Water Snakes (Squamata: Colubridae: Grayia), Teslin Chaney

Open Access Theses & Dissertations

Grayia is a genus of relatively large (1.5 - 2.5 m) aquatic Afrotropical snakes. Recent molecular phylogenies recovered Grayia in its own distinct subfamily (Grayiinae), which was strongly supported as the sister group to Colubrinae. Because tropical African snakes are generally understudied, the relationships within Grayia are poorly known. Due to high degrees of intra- and interspecies variation, identification is often difficult and previous studies involving Grayia included misidentified specimens in other genera. The goal of this study is to create a phylogenetic tree that can be used to understand the relationships and taxonomy of Grayia via an integrative taxonomic …


Linking Decomposition Reactions In Arctic Soils To Microbial Enzyme Production, Jane Karen Martinez May 2023

Linking Decomposition Reactions In Arctic Soils To Microbial Enzyme Production, Jane Karen Martinez

Open Access Theses & Dissertations

Microbial processes such as soil enzyme production are a major driver of decomposition and a current topic of interest in arctic soils due to the effects of climate warming. Despite the advances in understanding soil enzymes, there are still knowledge gaps regarding the role of enzymes in decomposition. In this dissertation, I addressed three of those gaps in the following chapters: (Ch.2) to explore the location of enzymes within the soil matrix, (Ch.3) to identify peptides matched to soil enzymes produced by microorganisms for organic matter decomposition, and (Ch.4) understand the longevity of enzymes in the soil after microbial production. …


Carbon Quantum Dots' Effects On The Structure And Function Of Neurodegenerative And Non-Neurodegenerative Associated Proteins, Shima Masoudi Asil May 2023

Carbon Quantum Dots' Effects On The Structure And Function Of Neurodegenerative And Non-Neurodegenerative Associated Proteins, Shima Masoudi Asil

Open Access Theses & Dissertations

Protein folding is an important physical process in which the sequences of polypeptides fold into a three-dimensional biological active structure. Misfolding is the conversion of a protein molecule into a structure unlike the native form, and therefore misfolded proteins have a strong tendency to aggregate and make fibrils. Amyloid aggregation is constituted by misfolded amyloidogenic proteins. Neurodegenerative diseases, such as Alzheimer’s Disease (AD), stem from the abnormal accumulation of harmful proteins, including Amyloid-ß peptides, tau protein, and the presynaptic protein α-synuclein in the nervous system. Alzheimer's disease is the most common neurodegenerative disorder that causes memory and learning deficits and …


We Travel Together: Examining The Drivers And Functions Of Animal Movement In Biotic Seed Dispersal, Binod Borah May 2023

We Travel Together: Examining The Drivers And Functions Of Animal Movement In Biotic Seed Dispersal, Binod Borah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plants and frugivorous animals exist in mutually beneficial relations, as these animals feed on fruits, ingest the seeds, and carry them away from the parent trees. Such dispersion of seeds over space helps them colonize new habitats, escape high mortality rates near their parent trees, and avoid competition with conspecifics. Therefore, seed dispersing animal movement can be critical for the persistence of plant populations. Yet what drives such seed disperser movement is often less understood and how it affects seed dispersal is little explored. In my dissertation, I investigate multiple drivers of seed disperser movement, link movement to potential seed …


Bone Metabolite Profile Differs Between Normal And Femur Head Necrosis (Fhn/Bco)-Affected Broilers: Implications For Dysregulated Metabolic Cascades In Fhn Pathophysiology, Alison Ramser, Rachel Hawken, Elizabeth Greene, Ron Okimoto, Brenda Flack, Courtney J. Christopher, Shawn R. Campagna, Sami Dridi May 2023

Bone Metabolite Profile Differs Between Normal And Femur Head Necrosis (Fhn/Bco)-Affected Broilers: Implications For Dysregulated Metabolic Cascades In Fhn Pathophysiology, Alison Ramser, Rachel Hawken, Elizabeth Greene, Ron Okimoto, Brenda Flack, Courtney J. Christopher, Shawn R. Campagna, Sami Dridi

Poultry Science Faculty Publications and Presentations

Femur head necrosis (FHN), also known as bacterial chondronecrosis with osteomyelitis (BCO), has remained an animal welfare and production concern for modern broilers regardless of efforts to select against it in primary breeder flocks. Characterized by the bacterial infection of weak bone, FHN has been found in birds without clinical lameness and remains only detectable via necropsy. This presents an opportunity to utilize untargeted metabolomics to elucidate potential non-invasive biomarkers and key causative pathways involved in FHN pathology. The current study used ultra-performance liquid chromatography coupled with high-resolution mass spectrometry (UPLC–HRMS) and identified a total of 152 metabolites. Mean intensity …


Effects Of Maternal Disease History On Provisioning, Brooding, And Offspring Outcomes, Sakura Roberts May 2023

Effects Of Maternal Disease History On Provisioning, Brooding, And Offspring Outcomes, Sakura Roberts

Biological Sciences Undergraduate Honors Theses

Disease within a population has the ability to shape the development, evolution, and general performance of a species. Pathogen exposure to hosts can influence their physiology and behavioral patterns to further shape offspring immunity. Parental conditions experienced by offspring during early development can benefit survival and fitness (e.g. increasing provisioning rates), as well as help deter against similar diseases experienced by parents. By testing if parental behavior changes can better prepare offspring outcomes for disease exposure, such as disease severity or duration of infection, we can see the beneficial impacts it has on disease dynamics and host-pathogen processes. Incubation temperature, …


Computational Modeling Of The Fanconi Anemia Gene Network And Its Connection To Cancer, Alyssa Warren-Belford May 2023

Computational Modeling Of The Fanconi Anemia Gene Network And Its Connection To Cancer, Alyssa Warren-Belford

Biological Sciences Undergraduate Honors Theses

Fanconi anemia (FA) is a rare genetic condition in which the cell’s DNA repair machinery is dysregulated, significantly increasing the chances of tumorigenesis. Further research is being done in order to improve patient outcomes and incidences of cancer. Our group created a computational model of the FA DNA repair gene network, which removes interstrand crosslinks found in damaged DNA and repairs it so DNA synthesis can continue. Computer simulations show the number of DNA damage indicators decreased as the pathway continued. This was expected as the FA pathway repairs DNA damage. The goal of this project was to provide further …


Identifying Nocturnal Pollinator Diversity In Apple Orchards In Northwest Arkansas, Emily Brown May 2023

Identifying Nocturnal Pollinator Diversity In Apple Orchards In Northwest Arkansas, Emily Brown

Biological Sciences Undergraduate Honors Theses

Insects have an essential role in nature, largely in part to pollination. These animals allow for many plants to reproduce and are directly involved in many of the earth’s fruit and vegetable supply. Bees, along with many other diurnal pollinators have gained the attention of the public, which has sparked debates and change to protect them. Many nocturnal species have previously been disregarded due to the assumption that diurnal pollinators provide the only significant pollinations, although recent studies show otherwise. For example, a recent study in apples suggests that nocturnal insects increase fruit production and flower cluster pollination at comparable …


Involvement Of Chromosome Remodeling Complexes On Chromosome Segregation, Adelle Warford May 2023

Involvement Of Chromosome Remodeling Complexes On Chromosome Segregation, Adelle Warford

Biological Sciences Undergraduate Honors Theses

Errors in chromosome segregation during cell replication are detrimental to the health of living cells. These errors cause aneuploidy: daughter cells with an incorrect number of chromosomes, as well as polyploidy: the complete duplication of a genome. In humans, these segregation errors are responsible for many harmful diseases and disorders. Using the model organism S. cerevisiae, a double mutant was created by removing two key chromosome remodeling complexes, SWR1 and INO80, both known to independently cause aneuploidy, decreased fitness, and damages the sensitivity of a cell's DNA (Andalis et al. 2004). By creating a double mutant strain, genetic cell …


Past And Present Patterns Of Neutral And Adaptive Genetic Diversity In Wild Mandrills (Mandrillus Sphinx), Anna Weber May 2023

Past And Present Patterns Of Neutral And Adaptive Genetic Diversity In Wild Mandrills (Mandrillus Sphinx), Anna Weber

LSU New Orleans Theses and Dissertations

Although primates have fascinated researchers and the public alike for generations, one species that has remained enigmatic is the mandrill (Mandrillus sphinx), a large Cercopithecine monkey endemic to Central Africa. Mandrills are currently in decline due to bushmeat hunting, urbanization, and habitat loss. Neutral and adaptive genetic diversity are important tools for understanding evolutionary history and future viability, since diversity influences a species’ ability to adapt to a changing environment. However, thus far, minimal genetic information has been available for wild mandrills. Because of the dense vegetation in their tropical forest habitat, studying wild mandrills has proven to …


Biochemical Characterization Of Fsa1572 From Fervidibacter Sacchari, The First Hyperthermophilic Gh50 With Β-1, 4-Glucanase Activity, Jonathan Covington May 2023

Biochemical Characterization Of Fsa1572 From Fervidibacter Sacchari, The First Hyperthermophilic Gh50 With Β-1, 4-Glucanase Activity, Jonathan Covington

UNLV Theses, Dissertations, Professional Papers, and Capstones

The bacterium Fervidibacter sacchari is an aerobic hyperthermophile that catabolizes various polysaccharides and is the only cultivated member of the class Fervidibacteria within the phylum Armatimonadota. Among its glycoside hydrolase (GH) cache is an enzyme from GH family 50 (GH50), an understudied family with only 25 characterized representatives and two known activities from 1,518 predicted members in the Carbohydrate-Active EnZyme (CAZy) Database. Here, we expressed, purified, and functionally characterized an extracellular GH50 from F. sacchari called Fsa1572. Using colorimetric assays, we show it has novel β-1,4-glucanase activity and only weak agarose activity that is typical for GH50 enzymes. The purified …


Long-Range Regulation By The Shigella Virulence Gene Regulator, Virb, Cody Cris May 2023

Long-Range Regulation By The Shigella Virulence Gene Regulator, Virb, Cody Cris

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nucleoid-structuring proteins (NSPs) in bacterial cells can exert gene regulatory effects over great distances on DNA. This contrasts with the traditional view of bacterial transcriptional regulation, where transcription factors bind cis-acting regulatory sites proximal (<250 bp) to promoters to influence gene expression. In Shigella species, the histone-like nucleoid-structuring protein (H-NS) transcriptionally silences many genes on the large (~220 kb) virulence plasmid. During host colonization, however, silencing by H-NS is alleviated by the anti-silencer protein, VirB, which remodels the H-NS:DNA complex. This transcriptional anti-silencing is mediated by VirB:DNA interactions and the modulation of DNA supercoiling, which lead to the up-regulation of virulence genes. VirB is a central regulator of Shigella virulence, but the mechanistic basis for transcriptional regulation is incompletely characterized. Here, I focus on the potential for VirB to regulate transcription from remotely located DNA binding sites. Employing complementary in vivo approaches, I assessed the spatial stringency of the VirB binding site and elucidated how varying cellular VirB levels impacts regulation over different distances. I also evaluated how a molecular roadblock on DNA influences remote regulation by VirB. Additionally, I developed control tools to validate the ability of VirB to spread along DNA, an activity of VirB that putatively drives transcriptional regulation. These data are consistent with transcriptional anti-silencing being driven by VirB spreading along DNA. Overall, these findings highlight how VirB is not a conventional transcriptional regulator and broaden our perspective on transcriptional control in bacteria. Furthermore, this work contributes to our understanding of long-range gene regulatory effects, which are frequently overlooked and poorly characterized in bacteria.


Desert Spring Prokaryotes And Benthic Macroinvertebrates: Geological And Ecological Controls, Ariel D. Friel May 2023

Desert Spring Prokaryotes And Benthic Macroinvertebrates: Geological And Ecological Controls, Ariel D. Friel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Desert springs are aquatic oases, being considered among the most diverse and imperiled ecosystems on Earth. Despite the ecological significance and threatened status of desert springs, few studies have surveyed the microorganisms in these systems or their interactions with other community members. The primary goal of this dissertation was to describe the major controls influencing the community ecology of prokaryotic and BMI communities in cold- and moderate-temperature desert springs of the southern hydrographic Great Basin. Chapter 1 provides a broad overview of spring ecosystems and of each chapter included in this dissertation. Chapter 2 documents the first-ever, regional-scale survey of …


Optimizing Resin Infiltration Treatment Of Post-Orthodontic White Spot Lesions By Increasing Infiltrant Penetration Duration — In Vitro Study, Hahnnah Park May 2023

Optimizing Resin Infiltration Treatment Of Post-Orthodontic White Spot Lesions By Increasing Infiltrant Penetration Duration — In Vitro Study, Hahnnah Park

UNLV Theses, Dissertations, Professional Papers, and Capstones

Background: This study focuses on evaluating the effect of increasing duration allowed for resin infiltrant penetration in improving the aesthetic outcome of resin infiltration treatment. Additional investigations into repeat treatment and long-term stability were also conducted. Artifically created white spot lesions were induced on one hundred extracted teeth made up of either incisors or canines. Teeth were divided into enamel and dentin groups depending on the extent of the lesion and then further subdivided into varying treatment protocol groups: 3-minute, 6-minute, and 9-minute penetration time. Teeth were thermocycled for one clinical year and then divided into a repeat treatment and …


Poop! There It Is! Anti-Germinants And Biological Variables As Modulators Of Clostridioides Difficile Infection (Cdi), Jacqueline Renee Phan May 2023

Poop! There It Is! Anti-Germinants And Biological Variables As Modulators Of Clostridioides Difficile Infection (Cdi), Jacqueline Renee Phan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Clostridioides difficile infection (CDI) is a major cause of antibiotic-associated diarrhea. Due to its insidious nature, the Centers for Disease Control and Prevention (CDC) has declared CDI an urgent threat. A key characteristic of C. difficile is its ability to form dormant spores that act as the infectious vehicles for disease. In the gut, spores recognize bile salts to germinate into toxin-producing cells.Dysbiosis of the gut microbiome is a key factor in allowing the C. difficile spores to germinate. Normal gut microbiota naturally protects from CDI. However, biological variables such as diet and sex have been found to modulate to …


The Effects Of Habitat Isolation On Fine-Scale Genetic And Geographic Structure Of Populations Of Two Threatened Endemic Insects In Southern Nevada, Pseudocotalpa Giulianii And Icaricia Shasta Charlestonensis, Kristen Tovar May 2023

The Effects Of Habitat Isolation On Fine-Scale Genetic And Geographic Structure Of Populations Of Two Threatened Endemic Insects In Southern Nevada, Pseudocotalpa Giulianii And Icaricia Shasta Charlestonensis, Kristen Tovar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Assessing the role geographic isolation and ecological specialization have on phylogeographic patterns contributes to our understanding of the evolutionary history of a species and the processes that erode genetic diversity. I used mitochondrial and nuclear genomic sequences to assess whether habitat isolation has shaped the fine-scale patterns of present-day genetic structure and diversity in two threatened insect species endemic to southern Nevada. Pseudocotalpa giulianii (Coleoptera; Scarabaeidae) is a dune obligate scarab beetle endemic to only two small, isolated sand dunes in Nye County, Nevada, with a usable habitat of less than 4.2 km sq that is impacted by on-going degradation. …