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Comparing Novel And Traditional Sampling Methodologies To Analyze The Population Status Of The Rio Grande Cooter (Pseudemys Gorzugi), Amy P. Bogolin May 2020

Comparing Novel And Traditional Sampling Methodologies To Analyze The Population Status Of The Rio Grande Cooter (Pseudemys Gorzugi), Amy P. Bogolin

Theses and Dissertations

The Rio Grande Cooter, Pseudemys gorzugi, is an understudied aquatic turtle species of conservation concern in the Rio Grande, Pecos, and Devils river systems. Traditional sampling methodologies for aquatic turtle species face numerous challenges, but novel sampling methodologies, such as drone-based surveys and environmental DNA analysis, may address these issues. This study compared novel sampling methodologies to traditional sampling methodologies in mean detections and identifications of aquatic turtle species, developed and implemented an environmental DNA assay to detect P. gorzugi, and characterized P. gorzugi habitat. Following an introductory chapter, each task is addressed by chapter and formatted to …


Lipid Analysis, Fluorescence Microscopy And Flow Cytometry As Tools To Evaluate Microalgae For Potential Biofuel Production, Giovanina Aimee Hinojosa May 2020

Lipid Analysis, Fluorescence Microscopy And Flow Cytometry As Tools To Evaluate Microalgae For Potential Biofuel Production, Giovanina Aimee Hinojosa

Theses and Dissertations

Petroleum-based crude oil is nonrenewable and toxic to the environment, leading to a need for a more efficient and environmentally effective replacement. Microalgae produce lipids which can be converted to recyclable biofuels; therefore, research in lipid production by algae is becoming important for an economic and environmental sustainability. Microalgae can re-absorb atmospheric CO2 and have rapid growth, thereby lowering greenhouse gasses (GHGs) emission, renewability, and simple growth requirements.

Nannochloris sp. is a marine microalga that is amenable for lipid production because there is little research on it so this study will focus on using flow cytometry, fluorescence microscopy and other …


Regional Differences In Wild North American River Otter (Lontra Canadensis) Behavior And Communication, Sarah Walkley May 2020

Regional Differences In Wild North American River Otter (Lontra Canadensis) Behavior And Communication, Sarah Walkley

Dissertations

This study focuses on the vocalization repertoires of wild North American river otters (Lontra canadensis) in New York and California. Although they are the same species, these two established populations of river otters are separated by a significant distance and are distinct from one another. River otters are semi-aquatic social predators that can be found throughout North America. This is the first study to examine the vocalizations of wild river otters, and results are compared across field sites in the different regions. River otter vocalizations and behaviors in New York were recorded using Bushnell Aggressor trail cameras that …


How Water Level And Irrigation Practices Affect Waterbird Community, Nesting, And Foraging Habitat Use On The Duck Valley Indian Reservation, Jamie L. Burke May 2020

How Water Level And Irrigation Practices Affect Waterbird Community, Nesting, And Foraging Habitat Use On The Duck Valley Indian Reservation, Jamie L. Burke

Boise State University Theses and Dissertations

Loss of habitat continues to threaten all bird populations. Despite efforts for conservation of wetlands, waterbirds continue to face habitat threats especially in western North America where water resources are limited across the landscape. The White-faced Ibis (Plegadis chihi) is a colonial nesting waterbird of conservation concern that builds nests in emergent vegetation of freshwater wetlands throughout the western United States. An ibis breeding colony site located at the Blue Creek Wetland complex on Duck Valley Indian Reservation may face habitat threats in the future due to plans intended to increase irrigation water use efficiency. Plans include manipulation …


Differences In Learning And Gene Expression In Brains Of Male And Female Bicyclus Anynana, Gabrielle Agcaoili May 2020

Differences In Learning And Gene Expression In Brains Of Male And Female Bicyclus Anynana, Gabrielle Agcaoili

Biological Sciences Undergraduate Honors Theses

One way to understand the variation in the behavior of animals is by looking at the genes involved. We were particularly interested in behavioral differences between the sexes. How might these differences be manifested in the brain? This study worked to answer this question by using male and female butterflies of the species Bicyclus anynana, examining what is going on in the brains of males and females as they learned from a social exposure. We focused in on how sex plays a role in behavior and learning; it has been seen that males and females respond to the same social …


Direct Evidence Of Missing Mepsps Using Ca2-Sensor Imaging, Petar Gajic May 2020

Direct Evidence Of Missing Mepsps Using Ca2-Sensor Imaging, Petar Gajic

Biological Sciences

Following an action potential in the presynaptic neuron there is evoked release of neurotransmitter into the synapse which activates ionotropic transmembrane receptors on the postsynaptic membrane that cause depolarizations in voltage that get recorded as excitatory postsynaptic potentials (EPSPs). In the absence of an action potential there is spontaneous release of neurotransmitter that postsynaptically gets recorded as miniature excitatory postsynaptic potentials (mEPSPs). According to the quantal hypothesis, postulated by Bernard Katz, the mEPSPs are allor- none changes in potential caused by a single quantum of neurotransmitter, which when added up create EPSPs. Following studies have found that these two modes …


The Effects Of The Atypical Dopamine Uptake Inhibitor Ce-158 On Extracellular Dopamine In The Nucleus Accumbens, Julia Neri May 2020

The Effects Of The Atypical Dopamine Uptake Inhibitor Ce-158 On Extracellular Dopamine In The Nucleus Accumbens, Julia Neri

Honors Scholar Theses

Major Depressive Disorder (MDD) is characterized by symptoms such as cognitive dysfunctions, inflammatory changes, and motivational symptoms such as amotivation, fatigue, and anergia. While depressed people are commonly treated by traditional antidepressants such as serotonin reuptake inhibitors (SSRIs), previous studies have reported that SSRI medications do not treat fatigue and anergia symptoms well, and in some cases, can even worsen those symptoms. Subjects treated with dopamine (DA) uptake inhibitors, on the other hand, have been less likely to report symptoms of anergia and fatigue compared to those treated with SSRIs. Common DA uptake inhibitors such as methylphenidate and amphetamines, however, …


The Effects Of Salvia Hispanica On Biochemical Markers Related To Immune System, Hormone Regulation, And Lumbar Vertebrae In Postmenopausal Rat Model, Daisy M. Mendez May 2020

The Effects Of Salvia Hispanica On Biochemical Markers Related To Immune System, Hormone Regulation, And Lumbar Vertebrae In Postmenopausal Rat Model, Daisy M. Mendez

Theses and Dissertations

In women, with age and menopause there is increase in body weight and decreased immunity and bone mass. Due to severe side effects of currently available drugs for obesity and bone loss, new therapies with less side effects are sought after and alternative medications are becoming more popular. Recently, Salvia hispanica (SH), a herbal supplement is implicated in losing body weight. Currently, there is no information on how SH modulates obesity or bone health. In this study, effects of SH seed extract was investigated in a postmenopausal rat model on certain hormones, immune markers, and fourth lumbar vertebrae. The highest …


Organizational Effects Of Exogenous Corticosterone On Vocal Development In A Wild Parrot, Rory Eggleston May 2020

Organizational Effects Of Exogenous Corticosterone On Vocal Development In A Wild Parrot, Rory Eggleston

Theses and Dissertations

Songbirds learn songs during a plastic phase in vocal development, similar to human vocal babbling. Research has focused on male song learning, a process influenced by gonadal steroids. Like humans, parrots are very plastic vocal learners and both sexes learn vocalizations throughout life. It is unclear how the endocrine system mediates environmental information with developing phenotypes in parrots. Corticosterone (CORT) is a sex-neutral hormone that can affect cognitive development, but its role in vocal development has not been experimentally tested in wild parrots. I quantified vocal babbling from nestling Green-rumped Parrotlets (Forpus passerinus) recorded in Venezuela. Nestlings received oral CORT-oil …


Effects Of Arbuscular Mycorrhizal Fungi (Amf) On Growth And Herbivore Defenses In Sorghum Sudangrass (Sorghum X Drummondii), Jasleen Kaur May 2020

Effects Of Arbuscular Mycorrhizal Fungi (Amf) On Growth And Herbivore Defenses In Sorghum Sudangrass (Sorghum X Drummondii), Jasleen Kaur

Theses and Dissertations

Chapter 2: In this chapter we have examined the role of trichomes in plant stress biology, reviewed the studies on herbivore X trichome interactions, and their role in plant defences. Ultimately, we have proposed new areas of research for future work.

Chapter 3: In this chapter, we examined whether AMF has cascading effects on insect community dynamics through attraction/repulsion of beneficial and damaging insects using Sorghum-sudangrass (Sorghum x drummondii), either inoculated with commercial AMF mix or left as control in lab and field experiments. Our results suggest positive effects of AMF on plant growth, and a lower initial incidence of …


Tobacco Enhances Bacterial-Induced Periodontal Bone Loss In Mice., Mina Iskander May 2020

Tobacco Enhances Bacterial-Induced Periodontal Bone Loss In Mice., Mina Iskander

Electronic Theses and Dissertations

Background: Tobacco smoking is the leading environmental risk factor for periodontal diseases. Delineation of the mechanisms underlying tobacco-induced or exacerbated periodontitis is hampered by the lack of an appropriate and reliable animal model. Hypothesis: We hypothesized that Porphyromonas-gingivalis-infected, cigarette smoke-exposed mice would represent reproducible models of acute (ligature model) and chronic (oral gavage model) tobacco-enhanced periodontitis that reflect multiple aspects of the disease noted in human smokers. Methods: In a chronic oral gavage disease model, Balb/c mice (6-8 weeks, 4 groups of n = 6 per group) were exposed to smoke produced by a Teague-10 smoking machine from 1R6F research …


Toxoplasma Gondii Requires Its Plant-Like Heme Biosynthesis Pathway For Infection, Amy Bergmann, Kathleen Floyd, Melanie Key, Carly Dameron, Kerrick C. Rees, L. Brock Thornton, Daniel C. Whitehead, Iqbal Hamza, Zhicheng Dou May 2020

Toxoplasma Gondii Requires Its Plant-Like Heme Biosynthesis Pathway For Infection, Amy Bergmann, Kathleen Floyd, Melanie Key, Carly Dameron, Kerrick C. Rees, L. Brock Thornton, Daniel C. Whitehead, Iqbal Hamza, Zhicheng Dou

Publications

Heme, an iron-containing organic ring, is essential for virtually all living organisms by serving as a prosthetic group in proteins that function in diverse cellular activities ranging from diatomic gas transport and sensing, to mitochondrial respiration, to detoxification. Cellular heme levels in microbial pathogens can be a composite of endogenous de novo synthesis or exogenous uptake of heme or heme synthesis intermediates. Intracellular pathogenic microbes switch routes for heme supply when heme availability fluctuates in their replicative environment throughout infection. Here, we show that Toxoplasma gondii, an obligate intracellular human pathogen, encodes a functional heme biosynthesis pathway. A chloroplast-derived …


Impact Of Epa And Dha Supplementation And 15-Lox-1 Expression On Colitis And Colitis-Associated Colorectal Cancer, Jonathan Jaoude May 2020

Impact Of Epa And Dha Supplementation And 15-Lox-1 Expression On Colitis And Colitis-Associated Colorectal Cancer, Jonathan Jaoude

Dissertations and Theses (Open Access)

Inflammatory bowel disease (IBD) patients not only suffer from colitis but also from increased morbidity and mortality of colitis-associated colorectal cancer (CAC). The enzyme 15-lipoxygenase-1 (15-LOX-1) is crucial to converting omega-3 fatty acid derivatives eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) to resolvins, potent anti-inflammatory products. 15-LOX-1 effects on the conversion of EPA and DHA to resolvins that subsequently exert anti-inflammatory and anti-tumorigenic effects have received little attention. To address this knowledge gap, we hypothesize that 15-LOX-1 expression in colonic epithelial cells is essential for resolvin biosynthesis from EPA and DHA to modulate immunophenotype, limit inflammation, promote resolution, and help …


Understanding Intercellular Signaling During Lung Injury-Repair, Margo Patricia Cain May 2020

Understanding Intercellular Signaling During Lung Injury-Repair, Margo Patricia Cain

Dissertations and Theses (Open Access)

The mammalian lung is a complex system of specialized cell types with precise spatial organization designed to cooperate to perform gas exchange. These cell types together coordinate organ development, homeostasis, and repair after injury through signals either presented or secreted, known as ligands, to be received by receptors on the surface of another, or in some cases, the same cell. The alveolar region of the lung, the primary region of gas exchange, responds to various types of injuries with different lung repair mechanisms. In order to explore how the various cell types in the lung communicate to drive tissue repair …


The Tropical Seagrass Halophila Stipulacea: Reviewing What We Know From Its Native And Invasive Habitats, Alongside Identifying Knowledge Gaps, Gidon Winters, Sven Beer, Demian A. Willette, Inés G. Viana, Kelcie L. Chiquillo, Pedro Beca-Carretero, Betty Villamayor, Tomás Azcárate-García, Rachamim Shem-Tov, Bridget Mwabvu, Luciana Migliore, Alice Rotini, Michelle A. Oscar, Jonathan Belmaker, Inbal Gamliel, Ana Alexandre, Aschwin H. Engelen, Gabriele Procaccini, Gil Rilov May 2020

The Tropical Seagrass Halophila Stipulacea: Reviewing What We Know From Its Native And Invasive Habitats, Alongside Identifying Knowledge Gaps, Gidon Winters, Sven Beer, Demian A. Willette, Inés G. Viana, Kelcie L. Chiquillo, Pedro Beca-Carretero, Betty Villamayor, Tomás Azcárate-García, Rachamim Shem-Tov, Bridget Mwabvu, Luciana Migliore, Alice Rotini, Michelle A. Oscar, Jonathan Belmaker, Inbal Gamliel, Ana Alexandre, Aschwin H. Engelen, Gabriele Procaccini, Gil Rilov

Biology Faculty Works

Halophila stipulacea is a small tropical seagrass, native to the Red Sea, Persian Gulf, and the Indian Ocean. It invaded the Mediterranean Sea 150 years ago as a Lessepsian migrant, but so far has remained in insulated, small populations across this basin. Surprisingly, in 2002 it was reported in the Caribbean Sea, where within less than two decades it spread to most of the Caribbean Island nations and reaching the South American continent. Unlike its invasion of Mediterranean, in the Caribbean H. stipulacea creates large, continuous populations in many areas. Reports from the Caribbean demonstrated the invasiveness of H. stipulacea …


Effects Of Management For Productivity On Adult Survival Of Snowy Plovers, Eleanor P. Gaines, Stephen J. Dinsmore, Michael T. Murphy May 2020

Effects Of Management For Productivity On Adult Survival Of Snowy Plovers, Eleanor P. Gaines, Stephen J. Dinsmore, Michael T. Murphy

Biology Faculty Publications and Presentations

Understanding the factors contributing to variation in demographic parameters and their influences on population growth is fundamental to effective conservation of small populations, but this information is often not available. Among shorebirds, population growth is generally most sensitive to changes in adult survival so understanding the factors affecting this vital rate is important. We used a long‐term mark–resight dataset and Program MARK to examine the effect of management actions, initiated to improve nesting productivity, on adult survival in a threatened population of Snowy Plovers (Charadrius nivosus ) in Oregon, USA. Apparent adult survival averaged 0.71 ± 0.01 (SE), but …


Exposure Of Phlebotomus Argentipes To Alpha-Cypermethrin, Permethrin, And Ddt Using Cdc Bottle Bioassays To Assess Insecticide Susceptibility, Jacob Rex Andersen May 2020

Exposure Of Phlebotomus Argentipes To Alpha-Cypermethrin, Permethrin, And Ddt Using Cdc Bottle Bioassays To Assess Insecticide Susceptibility, Jacob Rex Andersen

Undergraduate Honors Capstone Projects

Background: Insecticide resistance for sand flies is a concern since sand flies are vectors for Leishmania spp. parasites which cause leishmaniasis affecting millions of people each year. The CDC bottle bioassay is used to assess resistance by comparing known insecticide diagnostic doses and diagnostic times from an insecticide-susceptible population. The objective of this study was to determine diagnostic doses and diagnostic times for α-cypermethrin and the lethal dose for 50% and 90% mortality for α-cypermethrin, permethrin, and DDT for Phlebotomus argentipes.

Methods: The CDC bottle bioassays were performed in 1,000 mL glass bottles with 15-25 sand flies from a laboratory …


Symbiosis And Immunity At The Tri-Kingdom Interface, Stephen Alexander Lazar May 2020

Symbiosis And Immunity At The Tri-Kingdom Interface, Stephen Alexander Lazar

Theses and Dissertations

The rise in global sea-surface temperatures drastically and adversely impacts coral reefs worldwide through coral bleaching, diseases, and subsequent coral mortality. Corals become bleached by the expulsion of endo-symbiotic dinoflagellates, which reduces host pigmentation. Coral bleaching can also lead to enhanced disease prevalence immediately after thermal-stress and during the associated re-uptake of symbiotic dinoflagellates. This aspect has yet to be thoroughly investigated. A model system is necessary to study the relationships between symbiosis and disease that has sufficient flexibility to include a variety of host symbionts as well as pathogens. For this dissertation project, Exaiptasia pallida was investigated as a …


Glare Reduction By Dark Facial Markings And Bills In Birds, Clara Lebow May 2020

Glare Reduction By Dark Facial Markings And Bills In Birds, Clara Lebow

Electronic Theses and Dissertations

Avian facial plumage, bill coloration, and feather microstructure may serve one or more adaptive functions. Several researchers have proposed that dark eyestripes, bills, and facial masks aid in reducing glare, however, there have been relatively few tests of this hypothesis. Dark facial markings have been shown to have an adaptive glare-reduction function in recent field studies of a few species, but this hypothesis has never been tested in a broad multispecies analysis. It is likely that feather microstructure influences feather brightness and has an effect on the efficacy of glare reduction properties of feathers. I examined the link between dark …


Effects Of Nicotine On Contextual Fear Conditioning In Adult Zebrafish (Danio Rerio), Brianna Fann May 2020

Effects Of Nicotine On Contextual Fear Conditioning In Adult Zebrafish (Danio Rerio), Brianna Fann

Undergraduate Theses and Capstone Projects

The goal of this experiment was to investigate the effects of nicotine in fear-conditioned zebrafish. Fear was analyzed by the presence of freezing, which was defined as the absence of movement for at least two consecutive seconds, excepting gill-related or ocular motions. Zebrafish have been used as subjects in many experiments to understand the effects of drugs on behavioral mecahnisms, but their memory processes have not been extensively studied. The present experiment investigated whether or not nicotine, given immediately after contextual fear conditioning, enhanced memory consolidation. Zebrafish were randomly categorized into two groups: placebo and high-dose nicotine (100mg/L). Individual fish …


Efficient Conditional Inactivation Of Rdh10 Reveals Important Role Of Retinoic Acid During Lung Branching Morphogenesis., Nhut Quang Huy Tran May 2020

Efficient Conditional Inactivation Of Rdh10 Reveals Important Role Of Retinoic Acid During Lung Branching Morphogenesis., Nhut Quang Huy Tran

Electronic Theses and Dissertations

Birth defects are complicated pathological processes. Many birth defects can be traced back to disrupted regulation of molecular signaling pathways during embryogenesis. One of the most important gene regulatory factors during embryo development is retinoic acid (RA). However, studying the specific roles of RA in each organ during embryogenesis in vivo is challenging. The Sandell laboratory has a conditional mutant mouse model that can potentially be used for studying the role of RA during embryogenesis by inducing stage-specific RA deficiency. This model allows retinol dehydrogenase 10 (Rdh10), a gene required for RA production, to be inactivated at a …


An Investigation Of The Impacts Of Traditional, Virtual, And Hybrid Biological Laboratories On College Students’ Achievement And Motivation To Learn Biology, Shavonda Jackson May 2020

An Investigation Of The Impacts Of Traditional, Virtual, And Hybrid Biological Laboratories On College Students’ Achievement And Motivation To Learn Biology, Shavonda Jackson

Dissertations

Virtual courses function in a different manner than traditional courses, therefore they require teaching methods and assessment techniques geared specifically to maximize this learning experience. Internet-based learning and distance-education are no longer new concepts in the science field. Because of this, many collegiate biology programs have created courses that can be taken virtual or hybrid. A number of experimental studies have had great influence in terms of the effects and impacts of educational technology in relation to virtual laboratories.

However, not many studies emphasize the impact of hybrid laboratories on student achievement or assess students’ motivation to learn in a …


Herbivory Changes Soil Microbial Communities And Greenhouse Gas Fluxes In High-Latitude Wetlands, Karen M. Foley May 2020

Herbivory Changes Soil Microbial Communities And Greenhouse Gas Fluxes In High-Latitude Wetlands, Karen M. Foley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Herbivory by migratory animals in high-latitude ecosystems is known to impact greenhouse gas emissions from soils. However, few studies quantify the relationships between changes herbivores make to plant communities and soil conditions, and the biological interactions soil organisms have with their environment that result in changes to greenhouse gas emissions. These relationships are important to understand because they capture important carbon-climate feedbacks that may have implications for climate change policy and land management decisions, especially since high-latitude systems are experiencing unprecedented changes in climate.

In the Yukon-Kuskokwim (Y-K) Delta in western Alaska, herbivory by migratory geese affects the magnitude of …


A Comparison Of Coyote Diets In Urban And Rural Habitats In The Piedmont Of South Carolina, Bethany Krug May 2020

A Comparison Of Coyote Diets In Urban And Rural Habitats In The Piedmont Of South Carolina, Bethany Krug

Graduate Theses

With increasing rates of urban expansion, interactions between humans and wildlife become inevitable. These urban environments present novel situations to native species, frequently resulting in their displacement or extirpation. However, some species, often referred to as “urban adapters”, have thrived in these landscapes. Coyotes (Canis latrans) are a prime example of a species that has adapted to exploit urban habitats. Coyotes are omnivores with food choices ranging from small/medium mammals to invertebrates depending on habitat. With their recent range expansion into the Southeast, little is known of their behavioral ecology in the region, especially details relating to their diet. Macroscopic …


Rapid Evolution Of Starvation Resistance In Drosophila: Physiological And Molecular Mechanisms, Austin Joseph Mckenna May 2020

Rapid Evolution Of Starvation Resistance In Drosophila: Physiological And Molecular Mechanisms, Austin Joseph Mckenna

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Gibbs lab has maintained starvation-selected Drosophila melanogaster for >130 generations. These starvation-selected flies evolved an obese phenotype with a suite of physiological differences compared to control-fed flies. Previous studies have shown that long-term starvation-selected Drosophila contain more lipids, have lower metabolic rates and develop more slowly than controls. This dissertation encompasses 1) Examining the molecular mechanisms contributing to starvation resistance, 2) Functional validation of the candidate plin1 allele, and 3) Rapid physiological and genomic evolution in starvation-selected Drosophila.

Starvation-selected Drosophila survive starvation conditions much longer than control-fed flies. This study took a simple approach to identify possible differences in …


Analysis Of The Spatial Distribution, And Recruitment Of Native And Non-Native Tunicate Species On Zostera Marina In New Jersey, Sarah Hoffman May 2020

Analysis Of The Spatial Distribution, And Recruitment Of Native And Non-Native Tunicate Species On Zostera Marina In New Jersey, Sarah Hoffman

Theses, Dissertations and Culminating Projects

Many tunicate species have invaded the Western North Atlantic coast in the last century. These tunicates can have negative impacts on important industries like shellfish aquaculture, but they also foul natural and anthropogenic surfaces leading to displacement of native communities. During the summer of 2017 and 2018, the spatial distribution and recruitment of tunicate species in Zostera marina (Eelgrass) beds in Barnegat Bay, New Jersey were assessed. Samples were collected during the summer by excavating all eelgrass from a 0.125m2 area. Samples were then assessed for tunicate presence, as well as percent coverage of tunicates. In 2017, Botrylloides violaceus was …


Do Chemical Cues Influence Giant Waterbug Belostoma Flumineum Say (Hemiptera: Belostomatidae) Turning Behavior?, Olivia Paradis May 2020

Do Chemical Cues Influence Giant Waterbug Belostoma Flumineum Say (Hemiptera: Belostomatidae) Turning Behavior?, Olivia Paradis

Theses, Dissertations and Culminating Projects

Lateral biases and alternation of directional turns influence impact navigation, foraging, and predator avoidance in diverse animal species. Extended alternating turn successions are known to reflect anti-predation escape behaviors of organisms in complex environments. This study examined the effects of chemosensory cues from bluegill sunfish, Lepomis macrochirus, red-eared slider turtles Trachemys scripta elegans, American bullfrogs, Rana catesbeiana, and conspecific giant waterbugs on turning behaviors of Belostoma flumineum in a multiple T-maze.

As a study population, B. flumineum were found to perform significantly different alternating turn behaviors than those predicted, but overall were not influenced by any one specific treatment. When …


Megafaunal Extinction In The Neotropics: A Landscape Approach, Angela Rozas Davila May 2020

Megafaunal Extinction In The Neotropics: A Landscape Approach, Angela Rozas Davila

Theses and Dissertations

A 20 million years reign of large terrestrial mammals, known as megafauna (animals over 45 kg), came to an end during the Pleistocene-Holocene transition. Particularly apparent in the Americas, the sudden extinction of Pleistocene megafauna has no equivalent in the fossil record as it only targeted large terrestrial animals. Early hypotheses explaining this extinction focused on climatic forcing and anthropogenic interactions, which included extensive hunting and/or landscape transformation. More recently, a third plausible explanation of megafaunal extinction has been the combined effects of climate-change and human influences; commonly referred to as the ‘synergistic effect of climate-humans’ hypothesis. The study of …


Impact Of Intracellular Hemin On N-Type Inactivation Of Voltage-Gated K+ Channels, Ina Coburger, Kefan Yang, Alisa Bernert, Eric Wiesel, Nirakar Sahoo, Sandip M. Swain, Toshinori Hoshi, Roland Schönherr, Stefan H. Heinemann May 2020

Impact Of Intracellular Hemin On N-Type Inactivation Of Voltage-Gated K+ Channels, Ina Coburger, Kefan Yang, Alisa Bernert, Eric Wiesel, Nirakar Sahoo, Sandip M. Swain, Toshinori Hoshi, Roland Schönherr, Stefan H. Heinemann

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

N-type inactivation of voltage-gated K+ channels is conferred by the N-terminal “ball” domains of select pore-forming α subunits or of auxiliary β subunits, and influences electrical cellular excitability. Here, we show that hemin impairs inactivation of K+ channels formed by Kv3.4 α subunits as well as that induced by the subunits Kvβ1.1, Kvβ1.2, and Kvβ3.1 when coexpressed with α subunits of the Kv1 subfamily. In Kvβ1.1, hemin interacts with cysteine and histidine residues in the N terminus (C7 and H10) with high affinity (EC50 100 nM). Similarly, rapid inactivation of Kv4.2 channels induced by the dipeptidyl peptidase-like protein DPP6a is …


A Comparison Of Egg Desiccation Tolerance And Development Under Different Temperatures For Three Common Aedes Mosquitoes, Shelby A. Hosch May 2020

A Comparison Of Egg Desiccation Tolerance And Development Under Different Temperatures For Three Common Aedes Mosquitoes, Shelby A. Hosch

Honors Theses

With the rise in global temperatures, invasive mosquito species like Aedes albopictus may be able to reach regions that were previously inhospitable to these species. Therefore, if A. albopictus were to potentially reach Puerto Rico, it would come into contact with the species of Aedes aegypti and Aedes mediovittatus in local containers, and it is unclear how the tropical temperatures and precipitation patterns would affect the co-occurrence of these three species. Egg desiccation and temperature dependent growth among the species were measured to test how these species hatched and developed during different humidity and temperature. It was hypothesized that there …