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Research Methods in Life Sciences Commons™
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Articles 1 - 30 of 31
Full-Text Articles in Research Methods in Life Sciences
Moisture Effects On Visible Near-Infrared And Mid-Infrared Soil Spectra And Strategies To Mitigate The Impact For Predictive Modeling, Francis Hettige Chamika Anuradha Silva
Moisture Effects On Visible Near-Infrared And Mid-Infrared Soil Spectra And Strategies To Mitigate The Impact For Predictive Modeling, Francis Hettige Chamika Anuradha Silva
Theses and Dissertations
Instrumental disparities and soil moisture are two of the key limitations in implementing spectroscopic techniques in the field. This study sought to address these challenges through two objectives. The first objective was to assess Visible-near infrared (VisNIR) and mid-infrared (MIR) spectroscopic approaches and explore the feasibility of transferring calibration models between laboratory and portable spectrometers. The second objective addressed the challenge of soil moisture and its impact on spectra. The portable spectrometers demonstrated comparable performance to their laboratory-based counterparts in both regions. Spiking with extra-weight, was the most effective calibration transfer method eliminating disparities between instruments. The samples were rewetted …
A Signal To Divide: Apoptotic Extracellular Vesicles As Carriers Of Mitogenic And Immunogenic Signals, Safia Essien, Safia Essien
A Signal To Divide: Apoptotic Extracellular Vesicles As Carriers Of Mitogenic And Immunogenic Signals, Safia Essien, Safia Essien
Dissertations & Theses (Open Access)
Efficient replacement of dead cells in epithelial tissue is crucial for maintaining barrier function and tissue homeostasis. Apoptotic cells can signal to neighboring cells to stimulate proliferation and compensate for cell loss and maintain overall cell numbers in normal physiology and cancer. While dying cells can transmit instructive cues to neighboring cells, the molecular mechanisms that induce cell division are not well understood. Recent evidence suggests that apoptotic bodies (ABs) or apoptotic extracellular vesicles (AEVs) mediate cell-to-cell communication and carry diverse biologically active cellular cargo which can influence cell proliferation. This dissertation visualizes and characterizes AEVs in larval zebrafish and …
Interactions Between Sediment Mechanical Structure And Infaunal Community Structure Following Physical Disturbance, William Cyrus Roger Clemo
Interactions Between Sediment Mechanical Structure And Infaunal Community Structure Following Physical Disturbance, William Cyrus Roger Clemo
<strong> Theses and Dissertations </strong>
Shallow, river-influenced coastal sediments are important for global carbon storage and nutrient cycling and provide a habitat for diverse communities of invertebrates (infauna). Elevated bed shear stress from extreme storms can resuspend, transport, and deposit sediments, disrupting the cohesive structure of muds, and sorting and depositing sand eroded from beaches. These physical disruptions can also resuspend or smother infauna, decreasing abundances and changing community structure. Infaunal activities such as burrowing, tube construction, and feeding can impact sediment structure and stability. However, little is known about how physical disturbance impacts short and long-term sediment habitat suitability and whether disturbance-tolerant infauna influence …
Demographics, Sexual Dimorphism, And Ecological Aspects Of Ambystoma Annulatum (Ringed Salamander) In Northwest Arkansas, Usa, Brian M. Becker
Demographics, Sexual Dimorphism, And Ecological Aspects Of Ambystoma Annulatum (Ringed Salamander) In Northwest Arkansas, Usa, Brian M. Becker
Graduate Theses and Dissertations
The need to study and monitor amphibian populations is increasing along with the threats to their population stability and persistence in nature. Northwest Arkansas is one of the fastest growing areas in the nation and with that growth comes rapid changes in land use, massive alterations to habitats, habitat loss, and the introduction of nonnative plants and animals. Ambystoma annulatum (Ringed Salamander) is an Ambystomatid endemic to the Ozark and Ouachita Mountains of southern Missouri, northern and western Arkansas, and eastern Oklahoma giving it a relatively small distribution compared to most Ambystoma. Therefore, Arkansas constitutes a significant portion of the …
In Vitro And In Vivo Evaluation Of Antimicrobial Activity, Oocyst Sporulation Rate, Oocyst Integrity And Oocyst Infectivity In Eimeria Maxima M6 Oocyst Suspensions Treated With Chlorhexidine Salts In Comparison With Potassium Dichromate, Lauren Laverty
Graduate Theses and Dissertations
Eimeria species oocysts cause coccidiosis, one of the costliest diseases in the poultry industry. Coccidiosis infections cause significant economic losses due to reduced performance in chickens and turkeys. The objective of this thesis was to determine fecal bacterial recovery from chlorhexidine (CHX) salt suspensions containing Eimeria maxima M6 oocysts and evaluate the effect of CHX salts on oocysts during long-term cold storage. For bacterial recovery experiments, CHX digluconate and CHX gluconate were tested at different concentrations on poultry fecal slurries during oocyst shedding. Eimeria maxima M6 oocysts were evaluated in CHX salt suspensions to test the effect on oocyst degradation …
Assessment Of Dietary Energy And Amino Acid Diet Formulation In The Modern Broilers, Matheus Freitas Costa
Assessment Of Dietary Energy And Amino Acid Diet Formulation In The Modern Broilers, Matheus Freitas Costa
Graduate Theses and Dissertations
As a result of the advancement of genetics, understanding broiler requirements for dietary energy and amino acids is essential for improving live performance and carcass characteristics. The energy system used to formulate diets in poultry is based on metabolizable energy (ME); this equation can be described as the total amount of energy in the feed minus gases and feces. However, the net energy (NE) system may be the best depiction of the energy utilized by birds for production and maintenance purposes once the heat increment (HI) is measured. Thus, a series of studies were conducted to establish the responsiveness of …
Human-Bat Interactions In A Disease Emergence Hotspot: Implications For Human Health And Bat Conservation, Reilly Tempest Jackson
Human-Bat Interactions In A Disease Emergence Hotspot: Implications For Human Health And Bat Conservation, Reilly Tempest Jackson
Graduate Theses and Dissertations
Bats are an ecologically important taxon that can host zoonotic pathogens. Globally, many bat species are synanthropic and live closely with humans, often roosting in man-made structures. The spatial overlap between humans and bats creates opportunities for human-bat contact, which can lead to human exposure to bat-borne pathogens and conflicts that cause bat mortality. Despite this risk, little is known about the drivers and characteristics of these human-bat interactions in buildings and work is needed to understand this aspect of the wildlife-urban interface. In Chapter I, I present a literature review that identifies the geographic and taxonomic trends in reported …
Deep Ocean Vehicle Applications And Modifications, Nichole "Nikki" T. Arm
Deep Ocean Vehicle Applications And Modifications, Nichole "Nikki" T. Arm
Master's Theses
This project had two primary goals: (1) to explore opportunities to further a deep-ocean vehicle’s reach using alternative pressure spheres, and (2) to implement an existing deep-ocean vehicle (lander) in active scientific research.
I gained a greater understanding of the limitations and design choices made for existing pressure spheres using Finite Element Analysis (FEA). My simplified FEA model predicted sphere failure for the existing 30% Fiber Glass 70% Nylon injection molded spheres at an external pressure of 3,954psi or 2,690m ocean-depth (only a 7.38% error compared to the tested minimum failure depth), so I determined it a valid model. I …
Effect Of Rearing Conditions On The Allocation Of Larval And Adult Acquired Essential And Nonessential Fatty Acids To Flight In Two Adult Lepidoptera: Danaus Plexippus And Mythimna Unipuncta, Libesha Anparasan
Electronic Thesis and Dissertation Repository
Insects which are nectivorous as adults acquire essential fatty acids, which are important for many biological processes, almost exclusively from the larval diet. Thus, adult allocation of this limited resource may result in trade-offs in migrant insects that delay reproduction. I used the true armyworm, Mythimna unipuncta, and monarch butterfly, Danaus plexippus, to test the hypothesis that environmental cues (fall migratory or summer reproductive) would influence the use of fatty acids during flight (0-6h). I used larval and adult diets manipulated isotopically (δ13C) and chromatographic analyses to determine fatty acid composition and source in the fat …
Evaluation Of The Virulence Potential Of Avian Pathogenic Escherichia Coli Isolated From Broiler Breeders With Colibacillosis In Mississippi, Jiddu Joseph
Theses and Dissertations
Avian pathogenic Escherichia coli (APEC) is a bacterium that is responsible for colibacillosis in birds. However, information about broiler breeder APEC isolates is limited, but the data is critical due to the transfer of this bacteria down the production pyramid to progenies resulting in high mortality. Therefore, we evaluated the phenotypic virulence characteristics of 28 isolates using embryo lethality and day-old chick challenge assays. Also, the in vitro adhesion and invasion potential of selected nine isolates were identified. Results showed more than 1/3rd of the isolates were highly virulent and the virulence increased as the number of virulence-associated genes …
Investigating The Age-Dependent Impact Of Lactate Dehydrogenase On Cognition In Flies And Mice, Ariel Khaya Frame
Investigating The Age-Dependent Impact Of Lactate Dehydrogenase On Cognition In Flies And Mice, Ariel Khaya Frame
Electronic Thesis and Dissertation Repository
Lactate is a carbohydrate breakdown product typically produced in astrocytes, a type of glial cell, and transported to neurons within the brain. This type of metabolic coupling is commonly referred to as the astrocyte neuron lactate shuttle (ANLS). While numerous studies have shown that the ANLS is involved in cognition in mammals few have taken into consideration sex differences, changes with age, or evolutionary conservation in invertebrates. Lactate metabolism is controlled by the enzymatic interconversion of pyruvate and lactate in a reaction catalyzed by lactate dehydrogenase (LDH). In this thesis I examined cognitive changes across lifespan affected by genetic manipulation …
An Evolutionary Comparative Study Of Congenital Stationary Night Blindness-Associated Trpm1 Genetic Variants Of Uncertain Significance In Horses And Humans Utilizing Caenorhabditis Elegans, Gabrielle Davis
Theses
Congenital stationary night blindness (CSNB) is a heterogeneous collection of genetic diseases affecting the eyes and vision in horses and humans. Current research has implicated several genetic mutations impacting different genes involved in phototransduction and signal transmission, including TRPM1. In horses, genetic mutations in TRPM1 also result in a leopard spotting pattern or leopard complex. The goal of this study is to examine the potential impact of CSNB associated TRPM1 missense variants of uncertain significance (VUS). Previous research in Caenorhabditis elegans have revealed an orthologous TRPM1 gene known as gon-2 that allows for comparative studies. The evolutionary relationship of …
Cadmium And Salinity Stressor Antagonism On Vallisneria Neotropicalis, Christopher P. Mikolaitis
Cadmium And Salinity Stressor Antagonism On Vallisneria Neotropicalis, Christopher P. Mikolaitis
<strong> Theses and Dissertations </strong>
Submerged macrophytes form the foundation of freshwater ecosystems. These organisms are sessile and are very susceptible to shifts in their environment. Heavy metals are of particular concern as they can be sequestered indefinitely in sediments and are readily taken up by rooted vegetation. In the presence of saltwater intrusions, these metals can interact with salt ions potentially changing their availability to submerged vegetation. In this study a freshwater macrophyte, Vallisneria neotropicalis, was used as a test species for interactive effects between Cd, a non-essential heavy metal, and salt stress. The metrics used to establish the individual as well as …
Evaluating The Impact Of Temperature And Artificial Light At Night On The Growth, Swimming Performance, And Corticosterone Levels Of Southern Leopard Frog (Lithobates Sphenocephalus) Tadpoles, Skylar Alexander
Honors Theses
Anthropogenic activities caused by urbanization have considerably altered our world’s ecosystems which has led to a global amphibian population decline. Encroaching and unyielding urbanization by humans has contributed to a rise in artificial light at night due to light pollution as well as increased temperature due to climate change. Both rising temperatures and artificial light at night (ALAN) have been shown to individually have negative effects on amphibian physiology such as increased stress and decreased behavior. However, due to the drastic nature of human imposition, amphibians typically encounter these anthropogenic stressors in combination. Therefore, it is important to understand how …
Reverse Genetics: Downregulating Chk-1 And Fasn-1 In The Gonads Of C. Elegans, Sam Thompson
Reverse Genetics: Downregulating Chk-1 And Fasn-1 In The Gonads Of C. Elegans, Sam Thompson
Undergraduate Theses
Despite its widespread use in research, the model organism C. elegans has several biological processes like gonadal development with potentially unexplored genetic regulators. Previous transcriptome analysis has identified several genes that are upregulated in a specific tissue or sex during the development of the somatic gonad in C. elegans (Kroetz et al. 2015) that have not been previously connected to this process. Of these genes, this research is concerned with chk-1 and fasn-1. Abrogating the expression of these genes in gonadal tissue during gonadogenesis could cause a change in phenotype for affected C. elegans that would aid in understanding these …
Sexual Dimorphism Of Glomerular Capillary Morphology In Rats, Zackarias Coker
Sexual Dimorphism Of Glomerular Capillary Morphology In Rats, Zackarias Coker
Undergraduate Honors Theses
Chronic kidney disease (CKD) progresses faster in males than females; however, the underlying mechanisms remain poorly understood. Sex differences in glomerular capillary morphology has been hypothesized to contribute, in part, to the increased susceptibility to hypertension-induced renal injury and CKD progression in males, but this has not been investigated. The goal of the present study was to assess glomerular capillary morphology in male vs. female rats with intact kidneys and after uninephrectomy (UNX). We hypothesized that glomerular capillary radii (RCAP) and length (LCAP) would be greater in male rats.
Male (n=4) and female (n=4) with intact …
Targeting Metabolic Alterations Associated With Smooth Muscle Α-Actin Pathogenic Variant Attenuates Moyamoya-Like Cerebrovascular Disease, Anita Kaw
Dissertations & Theses (Open Access)
Heterozygous pathogenic variants in ACTA2, encoding smooth muscle α-actin (α-SMA), predispose to thoracic aortic aneurysms and dissections. De novo missense variants disrupting ACTA2 arginine 179 (p.Arg179) cause a multisystemic disease termed smooth muscle dysfunction syndrome (SMDS), which is characterized by early onset thoracic aortic disease and moyamoya disease-like (MMD) cerebrovascular disease. The MMD-like cerebrovascular disease in SMDS patients is marked by bilateral steno-occlusive lesions in the distal internal carotid arteries (ICAs) and their branches. To study the molecular mechanisms that underlie the ACTA2 p.Arg179 variants, a smooth muscle-specific Cre-lox knock-in mouse model of the heterozygous Acta2 R179C variant, termed …
Fecal Pellet Production By North Atlantic Zooplankton, Michael Gibson
Fecal Pellet Production By North Atlantic Zooplankton, Michael Gibson
Undergraduate Honors Theses
Fecal pellet carbon (FPC) production by zooplankton is a significant component of the ocean’s biological carbon pump: the suite of biological processes that mediate export of carbon to the deep ocean, ultimately leading to the sequestration of atmospheric carbon dioxide in the ocean. In this study, mesozooplankton (zooplankton 0.2 mm to ~2 cm) were collected from the epipelagic zone in the temperate North Atlantic Ocean during day and night in May 2021. Zooplankton were live separated into five size fractions and incubated on board ship in natural surface seawater to measure fecal pellet production rate of the mixed mesozooplankton community. …
Characterizing And Evaluating Growth Performance And Poultry Production Efficiencies Using Conventional And Novel Monitoring Methods On Modern Broilers And Japanese Quail, Travis Tabler
Graduate Theses and Dissertations
The poultry industry is integral to the global agricultural system as consumption rates continue to rise worldwide. With the global population projected to reach 10 billion by 2050, there is an increasing need for efficient and sustainable animal protein sources. Feed efficiency is a significant factor in poultry production costs, as feed accounts for 50 to 70% of total production costs. Given increasing concerns surrounding feed efficiency improvements, there is a focus on the genetic improvement of broiler digestibility to improve nutrient utilization and reduce production costs. Water availability is also of critical concern for the poultry industry, as estimates …
An Ecological Perspective Of American Rodent-Borne Orthohantavirus Surveillance, Nathaniel Mull
An Ecological Perspective Of American Rodent-Borne Orthohantavirus Surveillance, Nathaniel Mull
Graduate Theses and Dissertations
Orthohantaviruses are a global group of viruses found primarily in rodents, though several viruses have also been found in shrews and moles. Many rodent-borne orthohantaviruses are capable of causing one of several diseases in humans, and the mortality associated with these diseases ranges from < 0.1% - 50% depending on the specific etiological virus. In North and South America, orthohantavirus research was ignited by an outbreak of severe disease in the Four Corners region of the United States in 1993. However, despite the discovery of over 20 orthohantaviruses in the Americas, our understanding of orthohantavirus ecology and virus-host dynamics in this region is still limited, and orthohantavirus surveillance is generally restricted in scope to select regions and small portions of host distributional ranges. In Chapter I, I present a literature review on the current understanding of American rodent-borne orthohantavirus ecology. This review focused on under-studied orthohantaviruses, addressing gaps in knowledge by extrapolating information from well-studied orthohantaviruses, general rodent ecology, and occassionally from Eurasian orthohantavirus-host ecology. There were several key conclusions generated from this review that warrant further research: 1) the large number of putative orthohantaviruses and gaps in orthohantavirus evolution necessitate further surveillance and characterization, 2) orthohantavirus traits differ and are more generalizable based on host taxonomy rather than geography, and 3) orthohantavirus host species are disproportionately found in grasslands and disturbed habitats. In Chapter II, I present a prioritized list of rodent species to target for orthohantavirus surveillance based on predictive modeling using machine learning. Probable orthohantavirus hosts were predicted based on traits of known orthohantavirus hosts using two different types of evidence: RT-PCR and virus isolation. Predicted host distributions were also mapped to identify geographic hotspots to spatially guide future surveillance efforts. In Chapter III, I present a framework for understanding and predicting orthohantavirus traits based on reservoir host phylogeny, as opposed to the traditional geographic dichotomy used to group orthohantaviruses. This framework establishes three distinct orthohantavirus groups: murid-borne orthohantaviruses, arvicoline-borne orthohantaviruses, and non-arvicoline cricetid-borne orthohantaviruses, which differ in several key traits, including the human disease they cause, transmission routes, and virus-host fidelity. In Chapter IV, I compare rodent communities and orthohantavirus prevalence among grassland management regimes. Sites that were periodically burned had high rodent diversity and a high proportion of grassland species. However, rodent seroprevalence for orthohantavirus was also highest in burned sites, representing a trade-off in habitat management outcomes. The high seroprevalence in burned sites is likely due to the robust populations supported by the high quality habitat resulting from prescribed burning. In Chapters V and VI, I describe Ozark virus and Sager Creek virus, two novel orthohantaviruses discovered from specimens collected during Chapter IV. Both chapters report full genome sequences of the respective viruses and compare both nucleotide and protein phylogenies with related orthohantaviruses. Additionally in Chapter VI, I support the genetic analyses with molecular and ecological characterizations, including seasonal fluctuations in host abundance, correlates of prevalence, evidence of virus shedding, and information on host cell susceptibility to Sager Creek virus.
Factors That Affect Home Range Of Timber Rattlesnakes (Crotalus Horridus) In Northwest Arkansas, Bannon Gallaher
Factors That Affect Home Range Of Timber Rattlesnakes (Crotalus Horridus) In Northwest Arkansas, Bannon Gallaher
Graduate Theses and Dissertations
Conservation of animal populations requires knowledge of their habitat and spatial needs. Quantifying spatial requirements involves the analysis of home range. We examined the effects of sex, body size (SVL), body condition (log mass/log SVL), and year on home range in Timber Rattlesnakes (Crotalus horridus) in Northwest Arkansas. Individual locality data from an ongoing, 22+ year radio-telemetry study in Madison Co., Arkansas were analyzed using both minimum convex polygon (MCP) and Kernel Density Estimates (KDE). Plots of the number of sequential observations versus home range (MCP and KDE) determined that a minimum of 25 locations per individual per active season …
Mitral Valve Imaging And Biomechanics: A Workflow Towards Computational Modeling And Validation, Sam Stephens
Mitral Valve Imaging And Biomechanics: A Workflow Towards Computational Modeling And Validation, Sam Stephens
Graduate Theses and Dissertations
The mitral valve serves a critical role in healthy cardiac function by ensuring the unidirectional flow of oxygenated blood from the left atrium into the left ventricle. It experiences the highest pressures found within the heart and its closure is the result of a complex interaction of several different structures that, furthermore, are unique to each individual. Despite the valve’s vital role however, the specific function of these constituent structures is not fully understood. This, confounded by its asymmetric, personalized nature, make surgical interventions for the mitral valve far less effective than for its neighboring aortic valve. Efforts to overcome …
Analysis Of Wild Rodent Gut Microbiota As A Function Of Exposure To Ticks And Tick-Borne Pathogens, Joshua Pandian
Analysis Of Wild Rodent Gut Microbiota As A Function Of Exposure To Ticks And Tick-Borne Pathogens, Joshua Pandian
Honors Theses
Due to advances in high-throughput parallel sequencing, researchers have conducted novel studies exploring relationships between microbiome compositions and different aspects of organism health. Some of these studies have shown that the gut microbiome of rodent models has effects on organism health and behavior and that infection with pathogens and the composition of the skin microbiome are linked to changes in gut microbiome composition. While previous studies have shown how vector microbiota impact vector behavior and pathogen transmission, the effect vectors have on reservoir species microbiomes has been a less prominent focus. We were interested in the relationships between tick parasitism, …
Movement, Behavior, And Trophic Ecology Of A Pelagic Predator Guild In The Eastern Tropical Pacific Ocean, Ryan Keith Logan
Movement, Behavior, And Trophic Ecology Of A Pelagic Predator Guild In The Eastern Tropical Pacific Ocean, Ryan Keith Logan
All HCAS Student Capstones, Theses, and Dissertations
Pelagic apex predators exert strong influences on ecological communities, and often support valuable commercial or recreational fisheries worldwide. Yet, due to their rarity and pelagic lifestyle, many species, such as billfishes, have proven particularly difficult to study at resolutions necessary to define dynamics of recovery from fishery interaction, physical interaction with environmental features and prey exploitation, and competitive interactions among other billfish predators. This leads to a paucity of knowledge on billfish ecology and habitat use, and hinders management efforts. With the ever-improving and miniaturization of technology and oceanographic datasets, the ability to define and quantify these interactions of fish …
Vertebral Endplate Structural Defects: Measurement, Prevalence And Associated Factors, Aliyu Lawan
Vertebral Endplate Structural Defects: Measurement, Prevalence And Associated Factors, Aliyu Lawan
Electronic Thesis and Dissertation Repository
Objective: To synthesize current knowledge on the association of endplate structural defects (EPSD) with back pain (BP), improve EPSD measurement, and investigate EPSD prevalence, distribution, and association with age and body mass index (BMI).
Methods: In study 1, a systematic review was conducted on five databases for studies reporting on the association between EPSD and BP. Studies 2 and 3 used CTs and mCTs of 19 embalmed cadavers to examine the diagnostic accuracy of common EPSD assessment methods, and to develop and validate a novel method. Study 4 used the novel method on 200 adult males’ MRI to estimate EPSD …
The Effects Of Sex On Zebrafish Bone Metabolism, Simon Bagatto
The Effects Of Sex On Zebrafish Bone Metabolism, Simon Bagatto
Williams Honors College, Honors Research Projects
I investigated the effects of diet and sex on zebrafish bone metabolism. Zebrafish were subjected to either a high-calorie or low-calorie diet over a five-week period. After this diet, zebrafish scales were used to measure alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) enzyme activity with a fluorescent substrate. The enzyme activities were markers of the osteoblasts (ALP) and the osteoclasts (TRAP). These data were compared among sex and diet of the zebrafish using a repeated measures ANOVA statistical test. I also measured the number of resorption lacunae per scale (another indicator of osteoclast activity). The results showed higher TRAP …
Epithelial Membrane Protein 3 (Emp3b) Is A Novel Regulator Of Sympathetic Nervous System Development In Zebrafish., Jessica M. White
Epithelial Membrane Protein 3 (Emp3b) Is A Novel Regulator Of Sympathetic Nervous System Development In Zebrafish., Jessica M. White
Theses and Dissertations
Notable progress has been made in understanding the development of the neural crest (NC). Neural crest cells (NCCs) can be divided into 4-5 subpopulations. A major lineage among trunk NC derivatives are sympathoadrenal (SA) cells, which give rise to the sympathetic nervous system (SNS). Trunk NCCs follow a ventromedial migration pathway where signals derived from the dorsal aorta instruct migrating NCCs to a SA cell fate. Defects in NC development can result in syndromes known as neurocristopathies. Neuroblastoma is one of the most common forms of pediatric cancer affecting nearly 800 infants each year in the United States (Takita et …
Determining Species-Specific False-Positive Rates Using Visual And Auditory Cues: A Case Study With Sagebrush Steppe Songbirds, Amelia K. Evavold
Determining Species-Specific False-Positive Rates Using Visual And Auditory Cues: A Case Study With Sagebrush Steppe Songbirds, Amelia K. Evavold
Undergraduate Theses, Professional Papers, and Capstone Artifacts
Errors in wildlife field data threaten to bias resulting abundance and occupancy estimates if not properly accounted for or minimized. Methods to account for false-positive errors in wildlife data have not been as thoroughly developed as those for false-negative errors despite false-positives being present across diverse wildlife taxa and study systems. The calibration method to account for false-positives involves assessing the field detection method to determine how often false-positive errors occur in the field data. Rates can then be incorporated into estimations based on the field data to improve estimation accuracy. This study presents an application of the calibration approach …
The Impact Of Hiv-1 Tat And Morphine On Spatial Distribution Of Drugs In The Brain., Austin M. Jones
The Impact Of Hiv-1 Tat And Morphine On Spatial Distribution Of Drugs In The Brain., Austin M. Jones
Theses and Dissertations
Despite combination antiretroviral therapy effectively suppressing HIV within the periphery, the central nervous system (CNS) remains affected by the virus. Approximately half of people living with HIV will experience HIV-associated neurocognitive disorders (HAND) or neuroHIV. Concurrent opioid use exacerbates neuroHIV by promoting neuroinflammation, viral replication, and potentially altering the antiretroviral concentrations within the brain.
Using a transgenic mouse that expresses the HIV-1 Tat protein, we examined the effects of Tat and morphine on antiretroviral accumulation and distribution and the effects of Tat on morphine accumulation within the brain using infrared matrix-assisted laser desorption electrospray ionization with mass spectrometry imaging (IR-MALDESI-MSI). …
Genetic Evaluation Of The Current Distribution And Possible Diffrentations Between Lasiurus Borealis And Lasiurus Frantzii In Southwestern North America, Zeinab M. Haidar
Genetic Evaluation Of The Current Distribution And Possible Diffrentations Between Lasiurus Borealis And Lasiurus Frantzii In Southwestern North America, Zeinab M. Haidar
Cal Poly Humboldt theses and projects
Several recent accounts of overlap and historic misidentifications regarding two species of the genus Lasiurus, Western red bat (Lasiurus frantzii) and Eastern red bat (Lasiurus borealis), have cast doubt on our understanding of their distribution, assumed spatial allopatry, and interactions in the United States Southwest. With the use of morphometrics and genetic sequencing, utilizing tissue collected from specimens throughout California and adjoining states, we have reassessed the current distribution, best practices for field identification, and genetic differentiation between both species. Appropriate species classification by region was achieved utilizing mitochondrial DNA, targeting the cytochrome c oxidase …