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2018

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Articles 3091 - 3120 of 3206

Full-Text Articles in Biology

Molecular Characterization Of The Mummichog (Fundulus Heteroclitus) Ovarian Steroidogenic Pathway And Implications For Exogenous Estrogen Effects During Follicular Development, Thiviya Kanagasabesan Jan 2018

Molecular Characterization Of The Mummichog (Fundulus Heteroclitus) Ovarian Steroidogenic Pathway And Implications For Exogenous Estrogen Effects During Follicular Development, Thiviya Kanagasabesan

Theses and Dissertations (Comprehensive)

This study investigated ovarian development in Fundulus heteroclitus (mummichog), through molecular characterization of key mediators in the ovarian steroidogenic pathway; these included ovarian StAR (steroidogenic acute regulatory protein), cytochrome P450 enzymes, estrogen receptors (ERα, ERβ1 and ERβ2), and gonadotropin receptors (FSHr and LHr); additionally, hepatic vitellogenin (VTG1) and ERs, and brain P450 aromatase (P450arom; CYP19b) were studied. Fish were staged into cortical alveolus, vitellogenic, early mature, late mature, and ovulating stages of maturation; blood (plasma), ovary (tissue and isolated ovarian follicles per stage), liver, and brains were collected. Testosterone (T), 17β-estradiol (E2) and maturation inducing steroid (MIS), measured …


Evidence For Extra-Gastric Expression Of The Proton Pump H+/K+ -Atpase In The Gills And Kidney Of The Teleost Oreochromis Niloticus, Ebtesam Barnawi Jan 2018

Evidence For Extra-Gastric Expression Of The Proton Pump H+/K+ -Atpase In The Gills And Kidney Of The Teleost Oreochromis Niloticus, Ebtesam Barnawi

Theses and Dissertations (Comprehensive)

It is well known that stomach acid secretion by oxynticopeptic cells of the gastric mucosa is accomplished by the H+/ K+-ATPase (HKA), which is comprised of the HKα1 (gene: atp4a) and HKβ (gene: atp4b) subunits. However, the role of the HKA in extra-gastric organs such as the gill and kidney is less clear especially in fishes. This pump may contribute to active ion and/or acid-base regulation either through direct ion transport or through secondary transport proteins against unfavorable concentration gradients via the energy derived from ATP hydrolysis. In the present work I have demonstrated …


Relationships Between Factors Influencing Biofilm Formation And Pathogen Retention In Complex Rhizosphere Microbial Communities, Aaron Coristine Jan 2018

Relationships Between Factors Influencing Biofilm Formation And Pathogen Retention In Complex Rhizosphere Microbial Communities, Aaron Coristine

Theses and Dissertations (Comprehensive)

Riparian wetlands are unique habitats facilitating all forms of life. The riverbanks of these environments provide ideal conditions for bacteria, plants, and higher organisms. Of particular interest to this research was the variation in microbial community structure at high, intermediate and poor water quality impacted areas. Assessing the capabilities of plants to retain microbial pathogens was identified. Root systems and corresponding soil are ideal locations for bacterial deposition, resulting in attachment at these areas. Biofilm production in these regions is important for long-term establishment, leading to persistence and potential naturalization. Opportunistic pathogens originating from mammalian fecal matter are introduced into …


Forensic Markers Of Lampricide Toxicity In Oncorhynchsus Mykiss, Chris White Jan 2018

Forensic Markers Of Lampricide Toxicity In Oncorhynchsus Mykiss, Chris White

Theses and Dissertations (Comprehensive)

The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) has been used for decades to control invasive sea lamprey (Petromyzon marinus) populations in the Great Lakes, normally with little harm to other fish populations. However, due to the nature of lampricide treatments and the chemical properties of TFM, adverse effects to non-target fishes and non-target mortality occasionally occur. However, investigations of non-target mortality can be complex, particularly if fish deaths are not noticed immediately, due to decomposition of the carcasses. The objectives of this thesis were to expose rainbow trout (Oncorhynchsus mykiss) to TFM in order to: (i) identify forensic markers …


Distribution And Stability Of The Lampricide 3-Trifluoromethyl-4-Nitrophenol (Tfm) In Non-Target Rainbow Trout (Oncorhynchus Mykiss) And White Sucker (Catostomus Commersonii), Darren Foubister Jan 2018

Distribution And Stability Of The Lampricide 3-Trifluoromethyl-4-Nitrophenol (Tfm) In Non-Target Rainbow Trout (Oncorhynchus Mykiss) And White Sucker (Catostomus Commersonii), Darren Foubister

Theses and Dissertations (Comprehensive)

The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) is applied to tributaries of the Great Lakes to control invasive sea lampreys (Petromyzon marinus). Although TFM is selectively toxic to larval sea lampreys, non-target mortality can occur during lampricide treatments. It is important to know whether or not TFM played a role in the death of these fishes, and the most direct means to do this is using forensic science principles. The objectives of this study were to: (i) determine the acute toxicity of TFM to the non-target fishes, rainbow trout (Oncorhynchus mykiss) and white sucker (Catostomus commersonii), and how the lampricide is …


Charecterization Of The Innate Immune Response In The Rat Intervertebral Disc At The Tissue And Cellular Level, Matthew Guerreiro Jan 2018

Charecterization Of The Innate Immune Response In The Rat Intervertebral Disc At The Tissue And Cellular Level, Matthew Guerreiro

Theses and Dissertations (Comprehensive)

Low back pain (LBP) affects up to 80% of the global population at some point during their life. The costs associated with LBP are estimated at $100 billion per year, putting significant strains on our healthcare system. As intervertebral disc (IVD) herniation is one of the major causes of LBP we decided to focus on herniation facilitated inflammatory responses, where damage caused by herniation triggers an innate immune response which likely results in pain, inflammation, and recruitment of specialized innate immune cells like macrophages to the affected area. Since the role of the inflammatory response is relatively uncharacterized in the …


Gill Structure & Function In Parasitic And Non-Parasitic Lampreys: The Effects Of Metamorphosis And Freshwater-Seawater Transfer, Julia Sunga Jan 2018

Gill Structure & Function In Parasitic And Non-Parasitic Lampreys: The Effects Of Metamorphosis And Freshwater-Seawater Transfer, Julia Sunga

Theses and Dissertations (Comprehensive)

Lamprey (Petromyzontiformes) are a phylogenetically ancient group of jawless fishes that begin their lives as filter-feeding larvae (ammocoetes) before undergoing a complex metamorphosis into juvenile lamprey that involves major changes to their internal and external body plan. Some parasitic species, such as the sea lamprey (Petromyzon marinus), migrate to sea following metamorphosis, where they use their oral discs and rasping tongue to attach to and ingest vast quantities of blood from fishes. Thus, sea lamprey have to counter the simultaneous challenges of hyposmoregulation in sea water and the generation of large quantities of ammonia due to the …


An Assessment Of The Plant And Mycorrhizal Community At Steeves Lake Shoreline, Colomac Mine, Nwt, Rebekah Hamp, Dr. Kevin Stevens Jan 2018

An Assessment Of The Plant And Mycorrhizal Community At Steeves Lake Shoreline, Colomac Mine, Nwt, Rebekah Hamp, Dr. Kevin Stevens

Theses and Dissertations (Comprehensive)

This study focused on the environmental impacts of mining and potential techniques to mitigate them. The goals of this study were to (1) Quantify vegetation and fungal colonization at a remediated mine site in northern Canada, and to determine if there were effects from petroleum hydrocarbon contamination, (2) Determine the response of northern plants inoculated with mycorrhizal fungi to diesel contamination. Mycorrhizal colonization was observed in field collected roots and trends in colonization and vegetation cover suggested that these communities were no longer impacted by residual contamination. Mean hyphal colonization of Elymus trachycaulus roots collected over two years was 47.3±3.8% …


Near-Surface Permafrost Ground Ice Characteristics And Ecological And Physical Drivers Of Transient Layer Ice Content In Discontinuous Permafrost, Jason Paul Jan 2018

Near-Surface Permafrost Ground Ice Characteristics And Ecological And Physical Drivers Of Transient Layer Ice Content In Discontinuous Permafrost, Jason Paul

Theses and Dissertations (Comprehensive)

Accelerated climate warming in northern regions is causing permafrost degradation, leading to the reduction of the areal extent of permafrost. Permafrost is the foundation for many northern ecosystems and communities, so its thaw can have important ecological and societal consequences. Thaw of ice-rich permafrost can cause subsidence of the ground surface proportional to excess ice content. Terrain settlement can cause ponding or damage to infrastructure. Following a surface disturbance that removes much of the vegetation cover, a shift in the ground thermal regime can cause an increase in active layer thickness and rapid thaw of the top portion of permafrost. …


Detection Of “Xisco” Gene For Identification Of Streptococcus Pneumoniae Isolates, Francisco Salvà-Serra, Gwendolyn Connolly, Edward Moore, Lucia Gonzales-Siles Jan 2018

Detection Of “Xisco” Gene For Identification Of Streptococcus Pneumoniae Isolates, Francisco Salvà-Serra, Gwendolyn Connolly, Edward Moore, Lucia Gonzales-Siles

Articles

We describe a PCR-assay differentiating Streptococcus pneumoniae from closely-related species of the Mitis group of the genus Streptococcus and identification of pneumococcus clinical isolates, based on the “Xisco” gene discriminatory marker. The complete “Xisco” gene sequence was observed in all S. pneumoniae genomes analyzed and absent in all non-pneumococcus genomes.


A Physical Biology, The Electron Neutrino Mass, And The Role Of Quantum Mechanics In Nature, Maurice Goodman Jan 2018

A Physical Biology, The Electron Neutrino Mass, And The Role Of Quantum Mechanics In Nature, Maurice Goodman

Articles

In science we need to remove physics and earth science from the fundamental sciences and treat Biology as a fundamental natural (physical) science. Attempts to keep Biology autonomous because it is holistic, from the physical sciences, are just disguised anthropocentrism. Physical sciences have holistic features also. The autonomy of Biology is at odds with a holistic, integrated, science and is preventing progress in science. For example, every cell needs a 'global' communication system to keep order and stability with rapid information transfer across cellular scales. We have yet to figure out how this is achieved. Over the last 30 years, …


Morphological And Behavioral Traits Associated With Locomotion In Lizards, Chase T. Kinsey Jan 2018

Morphological And Behavioral Traits Associated With Locomotion In Lizards, Chase T. Kinsey

College of Graduate Studies: Theses & Dissertations

Morphology, locomotion, and behavior are co-adapted to optimize performance and ultimately fitness. Successfully navigating a complex environment is dictated by an animal’s locomotor behavior, and for some behaviors, its locomotor performance. The locomotor performance of an organism is directly related to the form and function of the structures involved in locomotion such that movement is efficient – that is, minimal loss of energy. The first chapter of this thesis focuses on the effects of obstacle placement and forelimb position on facultative bipedalism. Placing an obstacle beyond a lizard’s acceleration threshold did not affect the frequency of bipedal posture. Furthermore, the …


Predictors Of Fish Assemblage Structure And Dynamics In Atlantic Coastal Plain Streams, Rebecca Scott Jan 2018

Predictors Of Fish Assemblage Structure And Dynamics In Atlantic Coastal Plain Streams, Rebecca Scott

College of Graduate Studies: Theses & Dissertations

Effective management of freshwater fishes requires a mechanistic understanding of the drivers of assemblage composition; in other words, what determines who is where and when. Stream fish assemblages are potentially influenced by environmental factors that act on multiple spatiotemporal scales, but the relative influence of these drivers may vary between geophysically distinct regions. This study sought to determine the patterns and drivers of fish taxonomic and functional assemblage composition in the coastal plain, a region possessing unique hydrologies, faunas, and physiochemical conditions. I addressed this goal using two complementary chapters, both of which utilized environmental and biotic data collected from …


Comparison Of Three Benthic Macroinvertebrate Passive Sampling Devices For Non-Wadeable Streams, Kelsey A. Laymon Jan 2018

Comparison Of Three Benthic Macroinvertebrate Passive Sampling Devices For Non-Wadeable Streams, Kelsey A. Laymon

College of Graduate Studies: Theses & Dissertations

Rivers and streams provide essential ecosystem services to the degree that the monitoring and maintenance of these systems becomes imperative. Biomonitoring provides managers and policymakers with the tools to make informed decisions, and macroinvertebrates are often the object of biomonitoring because they are ubiquitous in most systems and are known to be good indicators of water quality. However, methods for sampling macroinvertebrates in non-wadeable streams (i.e., large rivers) have not been standardized across states and regions and an established method for macroinvertebrate biomonitoring in large rivers of Georgia is not currently available. My study compared macroinvertebrates collected with three types …


Crispr Genetic Editing: Paths For Christian Acceptance And Analysis Of In Vivo And In Vitro Efficiency, Mandeep Sandhu Jan 2018

Crispr Genetic Editing: Paths For Christian Acceptance And Analysis Of In Vivo And In Vitro Efficiency, Mandeep Sandhu

Scripps Senior Theses

With advancements in CRISPR-cas9 broadening the potential paths for clinical usage of genetic editing, conversations about genetic editing have grown to outside simply scientific communities and into mainstream conversations. This study focuses specifically on Christian discourse of genetic editing and locates four major tensions for many Christians when they think about genetic editing: beginning of life, Creator-human relationship, imago Dei, and stewardship. With these major concerns in mind, I identify epigenetics, somatic cell genetic editing, and in vivo genetic editing research as important research paths to pursue as they can potentially produce techniques that more Christian individuals would feel comfortable …


The Mechanism Responsible For Mechanically Enhanced Cancer Cell Invasion, Alexander Nicholas Gasparski Jan 2018

The Mechanism Responsible For Mechanically Enhanced Cancer Cell Invasion, Alexander Nicholas Gasparski

Wayne State University Dissertations

Cell invasion is an important process utilized by cancer cells to progress through the metastatic cascade to form deadly secondary tumors. This process can be influenced by the wide array of biomechanical forces that cancer cells within and around a tumor face in their microenvironment. It is not completely clear how these forces, either alone or simultaneously combined with other forces, can impact the metastatic capacity of cancer cells. To address this, we have utilized an in vitro mechano-invasion assay to mimic a transient tugging force that exists within the tumor microenvironment caused by the remodeling of the extracellular matrix …


Comparative Toxicology Of Nio And Ni(Oh)₂ Nanoparticles, Melissa Hope Cambre Jan 2018

Comparative Toxicology Of Nio And Ni(Oh)₂ Nanoparticles, Melissa Hope Cambre

Masters Theses

“Understanding the potential toxicity of nanoparticles (NPs) is important to ensure that these new products do not impose harmful effects to human and environmental health. Paper I is a literature review in which we discuss characteristics of nanomaterials, with an emphasis on transition metal oxide nanoparticles that influence cytotoxicity. Identification of those properties may lead to the design of more efficient and safer nanosized products for various industrial purposes and provide guidance for assessment of human and environmental health risk. We then investigate biochemical and molecular mechanisms of cytotoxicity that include oxidative stress-induced cellular events and alteration of the pathways …


Fluid Flow In A Krogh Cylinder: A Model For A Single Capillary And Surrounding Tissue, Xianjie Qiu Jan 2018

Fluid Flow In A Krogh Cylinder: A Model For A Single Capillary And Surrounding Tissue, Xianjie Qiu

Masters Theses

"A model describing the flow of plasma from the capillaries to the interstitial space in the extravascular tissue and back into the capillaries is constructed and solved. The flow through the tissue or the interstitial spaces is described by the Brinkman equation for porous medium, modified to account for the presence of cells considered as spheres. The flow of blood through the capillaries is considered to be that of a Newtonian fluid. The flow between capillary and tissue is coupled by the permeability of the capillary wall. The nature of flow and its magnitude was found to be highly dependent …


Untangling The Effects Of Biosynthetic And Metabolic Rates On Oxidative Cellular Damage In An Insect Model, Nikki Jihui Gomez Jan 2018

Untangling The Effects Of Biosynthetic And Metabolic Rates On Oxidative Cellular Damage In An Insect Model, Nikki Jihui Gomez

Masters Theses

“Previously, a theoretical model for unravelling the entwined effects of metabolic and biosynthetic rates on oxidative cellular damage accumulation during an animal’s growth period was developed and tested in hornworms (Manduca sexta larvae). In theory, if an animal had unrestricted amounts of energy and a high repair efficiency, they could repair most of the oxidative cellular damage accumulated, regardless of how their metabolic rate varies. However, organisms have a finite amount of energy that is allocated to repair and, during the animal’s development period, a considerable amount of energy goes towards growth eliciting a tradeoff between biosynthesis and repair. …


The Distinction Of The Interactions Between The Transmembrane Domains Of Basigin Gene Products And Monocarboxylate Transporters, Joseph D. Fong Jan 2018

The Distinction Of The Interactions Between The Transmembrane Domains Of Basigin Gene Products And Monocarboxylate Transporters, Joseph D. Fong

UNF Graduate Theses and Dissertations

Although it was once thought that neurons solely rely on glucose as a substrate for cellular energy production, it is now known that small monocarboxylate molecules, like pyruvate, lactate, and ketone bodies, are also utilized. Monocarboxylates are transported across plasma membranes via facilitated diffusion using a family of transport proteins known as monocarboxylate transporters (MCTs). Four MCTs (MCT1, MCT2, MCT3, and MCT4) are expressed within neural tissues. Expression of the MCTs has been tied to co-expression of a cell adhesion molecule belonging to the Basigin subset of the immunoglobulin superfamily (IgSF). Basigin gene products are known to interact with MCT1 …


Detection Of Cyanotoxins (Microcystins/Nodularins) In Hepatic Tissues And Epidermal Mats Of Stranded Bottlenose Dolphins (Tursiops Truncatus) In Northeast Florida, Amber Brown Jan 2018

Detection Of Cyanotoxins (Microcystins/Nodularins) In Hepatic Tissues And Epidermal Mats Of Stranded Bottlenose Dolphins (Tursiops Truncatus) In Northeast Florida, Amber Brown

UNF Graduate Theses and Dissertations

The St. Johns River (SJR; Jacksonville, FL, USA) is a large, brackish, estuarine system characterized by considerable anthropogenic pollution, recurrent harmful algal blooms (HABs), and diverse toxin-producing cyanobacteria. The most prevalent toxins in SJR water samples are microcystins/nodularins (MCs/NODs). Additionally, the SJR provides critical habitat for a genetically and behaviorally distinct estuarine community of bottlenose dolphins (Tursiops truncatus) that routinely uses and strands in low mesohaline and oligohaline areas of the river. This population has been subject to two unusual mortality events (UME) since 2010 and has since been described as having substantial declines in population health, characterized …


Tetratricopeptide 39c (Ttc39c) Is Upregulated During Skeletal Muscle Atrophy And Is Necessary For Muscle Cell Differentiation, Caleb Hayes Jan 2018

Tetratricopeptide 39c (Ttc39c) Is Upregulated During Skeletal Muscle Atrophy And Is Necessary For Muscle Cell Differentiation, Caleb Hayes

UNF Graduate Theses and Dissertations

Ttc39c has been identified as a novel gene in skeletal muscle that is upregulated in response to neurogenic atrophy in mice. Quantitative PCR and Western blot analysis confirmed that Ttc39c is expressed in both proliferating and differentiated muscle cells. Furthermore, comparison of Ttc39c expression in undifferentiated and differentiated C2C12 cells demonstrated that Ttc39c levels peak in early differentiation, but decreases as cells become fully differentiated myotubes. The transcriptional regulation of Ttc39c was examined by cloning promoter fragments of the gene and fusing it with the SEAP reporter gene. The Ttc39c reporter gene constructs were transfected into muscle …


Characterization Of Vitellogenesis In The Bonnethead Shark Sphyrna Tiburo, Adrien Kathleen Mowle Jan 2018

Characterization Of Vitellogenesis In The Bonnethead Shark Sphyrna Tiburo, Adrien Kathleen Mowle

UNF Graduate Theses and Dissertations

Vitellogenin (Vtg) is a precursor to yolk-proteins produced in the liver of many invertebrates and non-mammalian vertebrates; its synthesis is stimulated by the hormone estradiol (E2). This study is the first to characterize vitellogenin synthesis in a placental viviparous elasmobranch, the yolk-sac placental bonnethead shark, Sphyrna tiburo. This study focused on determining where and when Vtg is produced, as well as what hormonal factors regulate Vtg production. The liver was confirmed as the site of Vtg production via immunohistochemistry. Immunoreactivity was also observed within granulosa cells of ovarian follicles; further experimentation is needed to determine if this is indicative …


Establishing Relationships Among Environmental Stressors, Host Immune Status, And Wasting Disease Susceptibility In The Dominant Seagrass Species Thalassia Testudinum, Paige Joy Duffin Jan 2018

Establishing Relationships Among Environmental Stressors, Host Immune Status, And Wasting Disease Susceptibility In The Dominant Seagrass Species Thalassia Testudinum, Paige Joy Duffin

UNF Graduate Theses and Dissertations

A growing body of evidence supports the observation that marine disease outbreaks, especially those caused by opportunistic pathogens, are increasing in frequency and severity. One genus of such pathogens, Labyrinthula, has been identified as the causative agent of seagrass wasting disease, an epidemic that has historically plagued seagrass beds around the world. It is suspected that pathogenicity is intimately linked to the ability of the host to initiate defense responses, but a lack of compelling evidence prevents any meaningful application of preliminary observations. This body of work investigated the roles of host genotype, host immune status, and environmental stressors …


Migratory Patterns And Population Genetic Structure In A Declining Wetland-Dependent Songbird, Matthew G. Desaix Jan 2018

Migratory Patterns And Population Genetic Structure In A Declining Wetland-Dependent Songbird, Matthew G. Desaix

Theses and Dissertations

Understanding migratory connectivity is essential for assessing the drivers behind population dynamics and for implementing effective management in migratory species. Genetic markers provide a means to describe migratory connectivity, as well as incorporate population genetic analyses, however genetic markers can be uninformative for species with weak genetic structure. In this study, we evaluate range-wide population genetic structure and migratory connectivity in the prothonotary warbler, Protonotaria citrea, a wetland-dependent neotropical migratory songbird, using high-resolution genetic markers. We reveal regional genetic structure between sampling sites in the Mississippi River Valley and the Atlantic Seaboard with overall weak genetic differentiation among populations …


Quantification Of Twist From The Central Lines Of Β-Strands, Tunazzina Islam, Michael Poteat, Jing He Jan 2018

Quantification Of Twist From The Central Lines Of Β-Strands, Tunazzina Islam, Michael Poteat, Jing He

Computer Science Faculty Publications

Since the discovery of right-handed twist of a β-strand, many studies have been conducted to understand the twist. Given the atomic structure of a protein, twist angles have been defined using atomic positions of the backbone. However, limited study is available to characterize twist when the atomic positions are not available, but the central lines of β-strands are. Recent studies in cryoelectron microscopy show that it is possible to predict the central lines of β-strands from a medium-resolution density map. Accurate measurement of twist angles is important in identification of β-strands from such density maps. We propose an effective method …


Pulmonary Alveolar Proteinosis- A Case Report, Renee M. Horner, Douglas S. Gardenhire, Ralph D. Zimmerman Jan 2018

Pulmonary Alveolar Proteinosis- A Case Report, Renee M. Horner, Douglas S. Gardenhire, Ralph D. Zimmerman

Internet Journal of Allied Health Sciences and Practice

ABSTRACT

Background: Pulmonary Alveolar Proteinosis (PAP) is a rare pulmonary disorder caused by a congregation of excessive lipoproteinaceous material in the alveolar spaces due to impaired surfactant metabolism. The congregation of the protein in the alveolar space leads to difficulty in breathing, impaired pulmonary immunity, and susceptibility to both opportunistic and acquired pulmonary infections. Although Pulmonary Alveolar Proteinosis is rare, there are potential treatments. Whole-lung lavage is the most widely accepted therapy and course of treatment. An additional form of therapy, GM-CSF stimulating therapy, uses recombinant deoxyribonucleic acid (DNA) technology to increase white cell production.

Purpose: The purpose …


Endocrine Responses To Repeated Adrenocorticotropic Hormone Administration In Free-Ranging Elephant, Molly Mccormley Jan 2018

Endocrine Responses To Repeated Adrenocorticotropic Hormone Administration In Free-Ranging Elephant, Molly Mccormley

University of the Pacific Theses and Dissertations

Understanding the physiological response of marine mammals to anthropogenic stressors can inform marine ecosystem conservation strategies. Stress stimulates release of glucocorticoid (GC) hormones, which increase energy substrate availability while suppressing energy-intensive processes. Exposure to repeated stressors can potentially affect an animal’s ability to respond to and recover from subsequent challenges. To assess the endocrine response of a marine mammal to repeated stressors, we administered adrenocorticotropic hormone (ACTH) to free-ranging juvenile northern elephant seals (Mirounga angustirostris; n=7) once daily for four days. ACTH administration induced significant, but transient (<24 h) elevation in circulating cortisol levels (p < 0.0001). These increases did not vary in magnitude between the first ACTH challenge on day 1 and the last challenge on day 4. In contrast, aldosterone levels remained elevated above baseline for at least 24 hours after each ACTH injection (p < 0.001), and responses were greater on day 4 than day 1 (p < 0.01). Total triiodothyronine (tT3) levels were decreased on day 4 relative to day 1 (p < 0.01), while reverse triiodothyronine (rT3) concentrations increased relative to baseline on days 1 and 4 (p < 0.001) in response to ACTH, indicating a suppression of thyroid hormone secretion. There was no effect of ACTH on the sex steroid dehydroepiandrosterone (DHEA). These results suggest that elephant seals are able to mount adrenal responses to multiple ACTH challenges. However, repeated stress results in facilitation of aldosterone secretion and suppression of tT3, which may impact osmoregulation and metabolism. We propose that aldosterone and tT3 are informative additional indicators of repeated stress in marine mammals.


Unknown And Cryptic Diversity In The Adelpha Serpa-Group, Cassidi Rush Jan 2018

Unknown And Cryptic Diversity In The Adelpha Serpa-Group, Cassidi Rush

University of the Pacific Theses and Dissertations

The tropics are host to incredible insect diversity. One of the most charismatic groups that exhibit this diversity are the butterflies. Despite the tropical butterfly fauna being heavily researched, there remains much hidden diversity in the form of undescribed life histories and cryptic species. This is especially true among the species rich Nymphalidae, the brush-footed butterflies. Species in the genus Adelpha are known to be “the most trying taxonomically of all nymphalids” DeVries (1987), and as such are fruitful ground for uncovering unknown diversity. About half of the species within Adelpha have undescribed life histories, while A. serpa stands out …


Spatial And Temporal Dynamics Of Batesian Mimicry Between Adelpha Californica And Limenitis Lorquini, Louis Albert Prusa Jan 2018

Spatial And Temporal Dynamics Of Batesian Mimicry Between Adelpha Californica And Limenitis Lorquini, Louis Albert Prusa

University of the Pacific Theses and Dissertations

Conspicuous coloration is one of the main ways that animals communicate. The use of eye-catching color patterns to warn predators of an unprofitable trait is referred to as aposematism. Once predators learn to recognize the color pattern, a new signaling niche becomes available where other species can share the same signal. This mimicry niche can involve a “hide in plain sight” strategy by mimicking or parasitizing this signal, with mimics lacking the defense and associated costs that make them unprofitable. This is termed Batesian mimicry, and it decreases predation by taking advantage of the memory and learning of the predator …