Biology Commons^™

Biochar Impacts On Soil And Sagebrush Seedling Establishment Across A Natural Recovery Gradient In The Sagebrush Steppe, Ashley Leavell

Boise State University Theses and Dissertations

Large areas of the sagebrush steppe are destroyed by wildfire, which catalyzes invasive species growth, increases soil nitrogen availability, reduces soil water retention, and disrupts soil symbiont-plant interactions. These changes in biogeochemical properties may explain why restoration success remains limited. Biochar is a soil amendment created from pyrolyzed plant biomass that may reduce soil N availability and increase water retention. Our study aims to evaluate whether changing soil properties using biochar may enhance the survival of sagebrush seedlings. We installed an experiment south of Boise, Idaho at a site that burned in 1983. Nursery-grown sagebrush seedlings were hand-planted in November …

Challenges Of The Fentanyl Epidemic: Understanding The Crisis, Analyzing The Analogs, And Investigating The Detection Methods, Sophia Hontzas

Graduate Student Dissertations, Theses, Capstones, and Portfolios

The fentanyl epidemic has become a significant public health concern, identified by a rise in overdose deaths pertaining to the use of illicitly manufactured fentanyl (IMF). In 2021 alone, there were 70,601 overdose deaths attributed to fentanyl, emphasizing the severity of the crisis. This paper discusses the challenges posed by fentanyl and its analogs, investigating the origins, market dynamics, biological impacts, and the issues with detection and regulation. While fentanyl was initially created as a potent pain reliever, its misuse has grown due to the presence of new analogs. Case studies provide insight into how fentanyl rose in popularity and …

Effects Of Hypoxia On Monocyte Differentiation And Macrophage Specification During Ischemic Heart Injury, Farid Faridovich Kadyrov

Arts & Sciences Graduate Student Theses and Dissertations

Myocardial infarction (MI) occurs following cessation of blood flow to an area of the heart and leads to ischemia, cardiomyocyte death, and inflammation. Chronically, MI initiates a compensatory process referred to as left ventricular remodeling, which is characterized by cardiomyocyte hypertrophy, fibrosis, and a decline in heart function. Left ventricular remodeling is central to the pathogenesis of heart failure. During myocardial infarction, Ly6chigh CCR2+ monocytes enter the heart and differentiate into a variety of macrophage populations including inflammatory CCR2+ macrophages. Resident cardiac macrophages are also present within the heart at homeostasis. Previous research from several groups has shown that once …

The Influence Of Oxidative Stress On Ion Homeostasis And Glycolysis Activation, With Implications For Neurological Health And Multiple Sclerosis, Xavier Hayes

Graduate Student Dissertations, Theses, Capstones, and Portfolios

Multiple sclerosis (MS) is a neurodegenerative disease in which the body’s immune system attacks its own tissues, notably the neural cells, and one of the contributing factors to this is oxidative stress. Oxidative stress is the build-up of reactive oxygen species ROS that causes oxidative damage to the cells. Chronic and environmental stressors are explored as significant factors that exacerbate these conditions by disrupting cellular processes and energy metabolism. The paper reviews current literature on MS, examining the interplay between oxidative stress, environmental factors, and genetic predispositions. Additionally, it discusses how these factors contribute to MS, where the immune system …

Avian Communities Monitored Along A Successional Chronosequence In Bottomland Hardwood Forests In The Lower Mississippi Alluvial Valley, Eamonn Alasdair Thurmond

Electronic Theses and Dissertations

Bottomland hardwood forests in the Lower Mississippi Alluvial Valley have been extensively reduced due to agriculture conversion and altered hydrology. Remnant forests have undergone further degradation from sources such as a lack of forest management, invasive species, and reduced regeneration of oaks (Quercus spp.). Recent restoration efforts of bottomland hardwood forests have focused on implementing wildlife forestry practices that prioritize restoring wildlife habitat while retaining profitable timber harvests. In this study I surveyed bird communities in bottomland hardwood forests in the Lower Mississippi Alluvial Valley along a successional chronosequence. Birds were sampled using automated recording units over 10 days …

Distribution Of Great Horned Owls (Bubo Virginianus) Near Breeding Grounds Of The Reintroduced Northern Aplomado Falcon (Falco Femoralis Septentrionalis) At Laguna Atascosa National Wildlife Refuge In Coastal South Texas, David Roman Bontrager

Boise State University Theses and Dissertations

Habitat change is the leading cause of species extinctions and declines worldwide. In addition to species losses, habitat changes can also alter species behavior, diet, and the way they interact with other species. Less than one percent of coastal grasslands and prairies in Texas, U.S.A. remain intact as a result of agriculture, urbanization, and woody plant encroachment. This loss of Texas grasslands has resulted in bottom-up impacts, including the extirpations of multiple species that inhabited these ecosystems, such as the Northern Aplomado Falcon (Falco femoralis septentrionalis), Attwater’s Prairie Chicken (Tympnuchus cupido attwateri), and Pronghorn (Antilocapra …

Associations Between Landscape Changes And Declines In Golden Eagle Territory Occupancy In The Morley Nelson Snake River Birds Of Prey National Conservation Area, Ashley Santiago

Boise State University Theses and Dissertations

Rapid loss of native shrubs and expansion of invasive annuals like cheatgrass (Bromus tectorum) have extensively altered shrub-steppe systems. Vegetation changes can have bottom-up effects on trophic interactions and ecosystem dynamics. Predators, like Golden Eagles (Aquila chrysaetos) that forage on shrub-reliant prey, may increase their territory size to cope with degraded habitat or abandon historically occupied territories. We used a multi-season occupancy model that accounted for imperfect detection to investigate the associations between landscape cover (i.e., shrub and annual herbaceous), fire history, neighbor density, and territory occupancy of 36 Golden Eagle nesting territories in the Morley …

An Analysis Of Fish Assemblages And Flow Regimes Upstream And Downstream Of Falcon Reservoir, Christopher J. Austin

Theses and Dissertations

The lower Rio Grande is regulated by Falcon and Amistad dams. Native fish species rely on the natural flow regime for habitat and spawning. I analyzed streamflow discharge and fish assemblages above and below Falcon Reservoir to assess potential impacts of dam impoundment. Fish collections were conducted by seine, and river discharge data was provided by the International Boundaries and Water Commission. I found significant differences in fish assemblages above vs below Falcon Reservoir, and the flow regime was significantly more altered downstream of Falcon Reservoir. I also identified two Species of Greatest Concern for Texas above Falcon Reservoir (Notropis …

The Functional Role Of The Dynorphin-Kappa Opioid Receptor System In Cocaine-Dependent Male Rats, Jessica Lord

Electronic Theses and Dissertations

Activation of the dynorphin-kappa opioid receptor (KOR) system produces a negative emotional state during drug withdrawal, thereby motivating continued cocaine-seeking behaviors. However, it is not clear whether dynorphin plays a functional role in the onset of compulsive cocaine-taking. Here, escalation of cocaine self-administration was significantly attenuated by pretreatment of a long-acting KOR antagonist, norbinaltorphimine (NBI), in long access (LgA; 6-hours) male rats, whereas there was no effect of NBI on short access (ShA; 1-hour) rats on a fixed or progressive ratio schedule of reinforcement. Additionally, optical density of prodynorphin was increased in the nucleus accumbens (NAc) core and shell, bed …

Effect Of Chemical Enhancers On Transdermal Delivery Of Amiloride For Management Of Resistant Hypertension, Oluwatosin Tabitha Leshaodo

Electronic Theses and Dissertations

Amiloride, a diuretic used for managing resistant hypertension, is hindered by low oral bioavailability and Gastrointestinal side effects, impacting patient compliance. This study investigates transdermal delivery as an alternative to reduce pill burden and improve adherence. Using dermatomed porcine ear skin, the research examined the passive transdermal delivery of amiloride and the effect of various chemical enhancers, including oleic acid, oleyl alcohol, tocopheryl polyethylene glycol succinate, and N-methyl-2-pyrrolidone, individually or in combination. A validated High-Performance Liquid Chromatography method, adhering to Internal Council for Harmonized guidelines (ICH), was employed for quantitative analysis. In vitro permeation studies, conducted using porcine skin and …

From Inbreeding To Admixture: How The Diverse Consequences Of Gene Flow Shape Evolutionary Dynamics And Population Viability, Amy L. Springer

All Graduate Theses and Dissertations, Fall 2023 to Present

When Homo sapiens traveled out of Africa and interbred with the Neanderthals of Europe, human genes spread into the Neanderthal population. Likewise, genes from Neanderthals spread into the human genome—genes humans still carry to this day. The process whereby genetic material from one population is spread to another is known as gene flow. Gene flow—or the absence thereof—can have critical consequences for a population’s health and survival. On one hand, if no gene flow occurs, mating among close relatives can lead to high levels of inbreeding. Inbreeding can have devastating consequences for the health of populations, in some cases even …

Microbiome Assembly And Function In The Solitary Mason Bee, Osmia Lignaria (Megachilidae), Bailey Crowley

All Graduate Theses and Dissertations, Fall 2023 to Present

Animal-microbe interactions can influence host biology, ecology, and evolution. The assembly and function of microbes found within animal hosts oftentimes depends on which species are involved. Advances in sequencing technologies have permitted the exploration of host-microbe interactions in a variety of animals, including bees. Early research aimed at understanding the microbiomes of social bees, such as honey bees and bumble bees, found that microbes prevent the spoilage of stored pollen, breakdown indigestible nutrients into smaller molecules available for uptake by the host, and also protect the host from pathogens. When environmental stressors, such as increased temperatures, disrupt the microbiome, the …

The Interactions Between Drought Tolerant Corn Hybrids And Plant Water-Stress On Weeds And Their Host Capability For Spider Mites, Mercy Adhiambo Odemba

All Graduate Theses and Dissertations, Fall 2023 to Present

With climate change, it is predicted that more frequent high temperatures and drought severity will lead to an increase in damage caused by pests that thrive under these conditions. Spider mite outbreaks, for example, are associated with plant waterstress and there is evidence that some weeds are more resilient and adapted to drought than some crops, leading to major concerns for the management of these two pest types. Weeds directly compete with crops for limited resources, but what is unclear is which weeds harbor spider mites and whether they exacerbate the impact of spider mites on corn crops under water-stressed …

Early Onset Alzheimer’S Disease Markers In Mouse Hippocampus Unveiled By Single-Cell Transcriptomic Analysis Following Cranial Radiotherapy, Tuba Aksoy

Dissertations and Theses (Open Access)

Cranial radiation therapy plays an integral role in the treatment of brain tumors but can lead to progressive cognitive deficits in survivors by mechanisms that are poorly understood. To develop preventive or mitigative strategies, it is crucial to better understand the underlying pathogenesis of radiation-induced cognitive impairments. The study investigated single-cell transcriptomics and DNA methylation changes as potential drivers of persistent cellular dysfunction after radiation exposure, specifically concentrating on the CA1-3 regions of the hippocampus and the prefrontal cortex due to their role in cognitive functions. Thirteen-week-old mice underwent whole-brain radiation at clinically relevant doses. Following whole-brain radiation, an assessment …

Exploring The Role Of The Arginine-Methylation Writer-Reader Pair Prmt5/Snd1 In Jak2-Mutant Myeloproliferative Neoplasms, Rocio Rubiano

Dissertations and Theses (Open Access)

Myeloproliferative neoplasms (MPNs) are a hematopoietic disease characterized by hyperproliferation of cells of the myeloid lineage for which current therapeutic options are limited. Discovered in 2005, the JAK2V617F mutation is the most common driver mutation in BCR-ABL negative MPNs, resulting in constitutive activation of the JAK2 protein and the JAK-STAT signaling pathway. A role for the methyltransferase activity of Protein Arginine Methyltransferase 5 (PRMT5) has been proposed in JAK2-mutant MPN, highlighting both a mechanism through which this mutation can drive disease progression and a potential mode of therapeutic intervention. Staphylococcal Nuclease Domain-Containing Protein 1 (SND1) is the effector molecule responsible …

The Role Of An Ultraconserved Long Non-Coding Rna In B-Cell Lymphomagenesis, Swati Mohapatra

Dissertations and Theses (Open Access)

Ultraconserved regions (UCRs) are genomic segments with perfect (100%) conservation between the orthologous regions of human, rat, and mouse genomes. UCRs can be transcribed into mono-exonic long non-coding RNAs (lncRNAs) known as transcribed ultraconserved regions (T-UCRs). These regions, despite lacking protein-coding potential, are increasingly recognized for their regulatory roles in gene expression, including the modulation of non-coding RNA (ncRNA) transcripts. NcRNAs play crucial roles in cellular processes, including oncogenic transformation, with emerging evidence revealing their ability to encode small peptides known as ncRNA-encoded peptides (ncPEPs). These peptides, originating from small open reading frames (smORFs), contribute to diverse cellular functions and …

Outcomes Of Different Steroid Dosing Regimens In Critical Covid-19 Pneumonia At A Kenyan Hospital: A Retrospective Cohort Study, John Odhiambo, Jasmit Shah, Nancy Kunyiha, Felix Riunga, Charles Makasa

Internal Medicine, East Africa

Background: Among therapeutic options for severe and critical COVID- 19 infection, dexamethasone six milligrams once daily for ten days has demonstrated mortality benefit and is guideline recommended at this dose. In practice, variable doses of steroids have been used, especially in critical care settings. Our study aimed to determine the pattern of steroid dosing and outcomes in terms of critical care mortality, occurrence of dysglycaemias, and occurrence of superadded infections in patients with critical COVID-19.

Methods: A retrospective cohort study was carried out on all eligible patients admitted to the Aga Khan University Hospital, Nairobi, with critical COVID-19 between 1st …

Pelvic Sucker Form And Function In Waterfall Climbing Gobies: Variation In Morphology And Adhesive Performance Can Inspire Biomimetic Innovation, Amanda Palecek Mcclung

All Dissertations

Adhesive systems have evolved in many animal lineages and have appeared multiple times among the fishes. Bioadhesion in the gobies, a group found around the world, plays a role in both station-holding and even climbing. Among the Hawaiian streams, we find four species of amphidromous gobies which must face predators as juveniles and climb streams up to hundreds of feet tall to reach adult habitats. These gobies exhibit a range of climbing and adhesive abilities that result in an elevation-dependent species stratification, in which increasingly proficient climbing species are found in streams at increasingly higher elevations. This group is therefore …

Diatom Abundance In The Polar Oceans Is Predicted By Genome Size, Wade R. Roberts, Adam M. Siepielski, Andrew J. Alverson

Biological Sciences Faculty Publications and Presentations

A principal goal in ecology is to identify the determinants of species abundances in nature. Body size has emerged as a fundamental and repeatable predictor of abundance, with smaller organisms occurring in greater numbers than larger ones. A biogeographic component, known as Bergmann’s rule, describes the preponderance, across taxonomic groups, of larger-bodied organisms in colder areas. Although undeniably important, the extent to which body size is the key trait underlying these patterns is unclear. We explored these questions in diatoms, unicellular algae of global importance for their roles in carbon fixation and energy flow through marine food webs. Using a …

A Robust Genome Assembly With Transcriptomic Data From The Striped Bark Scorpion, Centruroides Vittatus, Tsunemi Yamashita, Douglas D. Rhoads, Jeff Pummill

Biological Sciences Faculty Publications and Presentations

Scorpions, a seemingly primitive, stinging arthropod taxa, are known to exhibit marked diversity in their venom components. These venoms are known for their human pathology, but they are also important as models for therapeutic and drug development applications. In this study, we report a high-quality genome assembly and annotation of the striped bark scorpion, Centruroides vittatus, created with several shotgun libraries. The final assembly is 760 Mb in size, with a BUSCO score of 97.8%, a 30.85% GC, and an N50 of 2.35 Mb. We estimated 36,189 proteins with 37.32% assigned to Gene Ontology (GO) terms in our GO …

Uvc And Planetary Habitability: Insights From Desert Lichens And Cyanobacteria, Tejinder Singh

UNLV Theses, Dissertations, Professional Papers, and Capstones

An important question in astrobiology is whether life can exist under the levels of UVC radiation found on Archean Earth, Mars, and exoplanets. We investigated this question by studying the UVC survival of colonial cyanobacterium and lichens that grow in harsh desert environments and possess natural sunscreens. We irradiated them nonstop in a desiccated state with a UVC flux closely representing the upper limit on those planets: 55-60 W/m². After irradiation, we rehydrated and assessed their survival using chlorophyll fluorometry and by counting the number of viable colonies that formed on agar plates. All three study organisms survived two to …

Probing The Ecological Functions Of Thermophiles Using Cultivation-Dependent And Cultivation-Independent Techniques, Dengxun Lai

UNLV Theses, Dissertations, Professional Papers, and Capstones

High-temperature geothermal springs are ecosystems that resemble early Earth, offering insights into the origins and early evolution of life. In these unique ecosystems, thermophilic microorganisms thrive. However, our knowledge of thermophiles remains limited. A major challenge is that many thermophiles remain uncultivated. The primary goal of this dissertation was to explore the diversity, metabolism, and ecological functions of thermophiles using cultivation-dependent and cultivation-independent approaches. Chapter 1 provides a broad overview of geothermal spring ecosystems and thermophiles, along with a roadmap of the dissertation. Chapter 2 documents a study on the response of specific thermophiles from Gongxiaoshe (GXS) Hot Spring in …

Analysis Of Malarial Impact: Understanding Disease Transmission, Epidemiology, And Effects On Fetal Life, Josey Sumpter

Graduate Student Dissertations, Theses, Capstones, and Portfolios

Malaria is a significant public health problem which mainly affects malaria endemic regions, such as parts of Africa, South America, and Western Asia. However, all hot and humid environments are susceptible to spread leading to a global scale. Malaria affects an estimated 200 million people each year, with about 600,000 cases resulting in death. Malaria is passed through the bites of infected female anopheles mosquitos, with one of the six Plasmodium genus parasites that are malarial causing. Once the parasite enters the blood stream it infects erythrocytes which can then spread throughout the entire body. Disease is often characterized by …

Impacts Of Anthropogenic Disturbances And Urbanization On The Behavior And Morphology Of Two Free-Living Lizard Species (Uta Stansburiana And Aspidoscelis Neotesselatus), Layne O. Sermersheim

All Graduate Theses and Dissertations, Fall 2023 to Present

Urbanization can alter wildlife, requiring species to adjust to anthropogenic changes via life history strategies. Reptiles are particularly vulnerable to these changes, as ectotherms directly rely on their environment to maintain their optimal homeostatic state. As urbanization changes the landscape, reptiles will have to adapt to anthropogenic change, but it is unclear what behaviors may be aiding in this adaptation and whether there are morphological tradeoffs existing to support this change. To analyze the impact of urbanization and anthropogenic disturbances on reptile behavior and morphology, I conducted three research studies on two different species – the common side-blotched lizard and …

Comparative Morphology And Development Of The Trigeminally Innervated Infrared-Imaging System In Boas And Pythons, Helen Bond Plylar

All Graduate Theses and Dissertations, Fall 2023 to Present

Boas and pythons use specialized sense organs called pit organs to detect radiant heat. Pit organs in these lineages occur in paired arrays along the upper and lower jaws and are served by the trigeminal nerve (the fifth cranial nerve and one of the largest). Information from the pit organs travels via branches of the trigeminal to the brain and ultimately is processed in the optic tectum, along with information from the visual system. That means these snakes effectively “see” heat. While studies of the pitviper infrared-imaging system are numerous, very few studies of this system in pythons or boas …

Partial Immunity To Mycoplasma Gallisepticum After An Initial Infection Is Long-Lasting And Reduces Transmission In Flocks Of Canaries, Madeline Sudnick

Graduate Theses and Dissertations

Pathology during a second infection can be influenced by immunity and an increase in resistance or tolerance of individuals. Population-level differences in the ability to maintain immunity can lead to contrasting survival outcomes between groups and determine how future outbreaks will spread. However, long term wildlife disease surveillance can be challenging due to lack of infrastructure and host-pathogen specific tests. Calculating disease transmission likelihood requires understanding individual-level heterogeneity in pathology and behavior, and there is limited knowledge in understanding how populations in different stages of an epidemic will transmit disease. In Chapter I, we aim to help fill a gap …

Effects Of Land Cover And Land Change On Monarch Butterfly Presence Across The Conus, Chris R. Burkhart

Graduate Theses and Dissertations

The decline of monarch butterfly populations (Danaus plexippus L.) over the past four decades, particularly in their overwintering habitats, has raised concerns about the species' conservation. Habitat loss and modification, particularly within the contiguous United States, are attributed as one of the key drivers of this decline. However, the specific impact of land use and land cover (LULC) changes on monarch distributions remains inadequately documented. This study integrates monarch observations from multiple sources spanning 2008 to 2019 with LULC data to analyze the relationship between habitat configuration and monarch presence. Using a randomized grid sampling approach, habitat configuration metrics were …

Influence Of Invasive Species, Drought, And Stream Permanence On Stream Crayfish Species With A Focus On The Imperiled Mammoth Spring Crayfish (Faxonius Marchandi), Leah Marie Bayer

Graduate Theses and Dissertations

Freshwater crayfish constitute one of the most-threatened taxonomic groups in North America. Invasion by other crayfish species as well as habitat degradation through alteration of natural flow regime are two of the most prominent threats to crayfish persistence. Additionally, extreme weather events like droughts can amplify threats posed by other stressors on crayfish populations and are expected to increase in frequency, magnitude, and/or duration in the future, which may negatively influence narrow-ranged endemic crayfish populations typical of the Southeast. The Mammoth Spring Crayfish, Faxonius marchandi, is a narrow-ranged endemic that occurs in the Spring River drainage of Arkansas and Missouri …

Spectral Sensitivity Of Circadian Entrainment In Araneoid And Non-Araneoid Spiders, Craig Campbell

Electronic Theses and Dissertations

Artificial lighting at night is a growing worldwide phenomenon that can negatively impact flora and fauna in the surrounding area. With new technology, there is now opportunity for change: newer LEDs can emit specific wavelengths of light that may be less ecologically damaging. In this study, we aim to describe the circadian spectral sensitivity of two phylogenetically distant urban spider species with similar life histories, the Araneoid Parasteatoda tepidariorum and non-Araneoid Pholcus manueli, to determine differences between them. We exposed these spiders to progressively dimmer levels of white, blue, green, or red light. Despite evidence that spiders lack visual …

Aging Antiviral Immunity In The Central Nervous System: Mechanisms And Implications, Artem D. Arutyunov

Arts & Sciences Graduate Student Theses and Dissertations

The complex interplay between aging, neuroinflammation, and neuroimmune responses has become increasingly evident in recent years. Microglia, the resident immune cells of the central nervous system (CNS), play a pivotal role in maintaining neural homeostasis and responding to neuroinflammatory triggers. This dissertation focuses on the role that aging plays in microglial activation and neuroinflammation, specifically in the context of West Nile Virus (WNV) encephalitis. While the incidence of WNV is consistent across age groups, the risk of West Nile Neuroinvasive Disease (WNND), a serious complication of WNV infection, increases with advanced age. Using mouse models of WNV infection, our group …