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Full-Text Articles in Life Sciences

Correlation Between Pluripotent Stem Cell Markers And Microrna Expression In Dental Pulp Stem Cells, Mark Whiting May 2019

Correlation Between Pluripotent Stem Cell Markers And Microrna Expression In Dental Pulp Stem Cells, Mark Whiting

UNLV Theses, Dissertations, Professional Papers, and Capstones

In human development there are many factors that cause our cells to form certain organs and systems with specific functions. These cells original start as stem cells before biological processes take over and cause differentiation into different cell lines. Since these undifferentiated stem cells have been discovered, many studies have been done to try and find the exact mechanism that causes a cell to change into another specific cell. Due to the multiple sources that stem cells can be harvest from the human body, this knowledge of how differentiation works could lead to breakthroughs in regenerative medicine.

Traditional biomarkers have ...


Effects Of Ecological Restoration Techniques In Glen Canyon National Recreation Area, Simone Ka-Voka Jackson May 2019

Effects Of Ecological Restoration Techniques In Glen Canyon National Recreation Area, Simone Ka-Voka Jackson

UNLV Theses, Dissertations, Professional Papers, and Capstones

A better understanding of key ecological restoration techniques can inform land management in the Southwest on restoration options for areas infested by invasive grasses that can pose threats to ecosystems, from changes in nutrient cycling to altered fire regimes. In the semi-arid desert of Glen Canyon National Recreation Area (GLCA), several exotic grasses pose risks to local ecosystems: Saccharum ravennae, a relatively new invasive perennial grass, and Bromus rubens and Bromus tectorum, widespread annual grasses. In this study, multiple ecological restoration techniques were implemented to assess their effects on native and nonnative vegetation on sites invaded by the non-native grasses ...


Assessing Minimal-Input Restoration Strategies For Desert Soil And Vegetation Restoration, Audrey Jean Rader May 2019

Assessing Minimal-Input Restoration Strategies For Desert Soil And Vegetation Restoration, Audrey Jean Rader

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Mojave and Sonoran Deserts have been negatively impacted by anthropogenic disturbances. Considering that these ecosystems may recover on millennial timescales, research has shown that restoration techniques can be fairly successful in initiating long-term recovery processes in these sensitive environments. However, uncertainty remains as to which techniques are effective in different circumstances, such as in different climates or across different soil properties, and which techniques may best avoid unintended consequences, such as facilitating non-native plants. To reduce fugitive dust as a human health hazard, increase soil stability, and enhance wildlife habitat, further work is necessary to develop restoration techniques for ...


Tree To Grass Water Use Ratios; Assessing Turfgrass’ High Water Use In The Urban Landscape, Tamara Wynne May 2019

Tree To Grass Water Use Ratios; Assessing Turfgrass’ High Water Use In The Urban Landscape, Tamara Wynne

UNLV Theses, Dissertations, Professional Papers, and Capstones

Water demand in the southwestern United States continues to rise. The population of the Las Vegas Valley doubled from 2000-2010 and now more than two million people call it home. The residential sector uses 60% of all water consumed in the valley. Outdoor urban landscape irrigation is responsible for 70% of all residential use. These landscapes are dominated by trees and turf grass. Although the water use of turf grass species is well studied, there are few published results about the water use of landscape trees in the desert southwest USA. To obtain a more complete picture of the tradeoffs ...


Expression Of Line-1 In Human Somatic Tissues And The Factors Correlated With Line- 1 Expression, G. M. Jonaid Aug 2018

Expression Of Line-1 In Human Somatic Tissues And The Factors Correlated With Line- 1 Expression, G. M. Jonaid

UNLV Theses, Dissertations, Professional Papers, and Capstones

Despite the long-held assumption that transposons are normally only expressed in the germline, recently we discovered that full length or partial transcripts of LINE1 are frequently found in the somatic cells. However, the extent of variation in LINE1 levels across different tissues and different individuals, and the genes and pathways that are co-expressed with LINE1 are unknown. Co-expressed genes may be candidate genes that are functioning in transposon silencing. Here, we report the extent of variation in L1HS expression levels across cancer tissues and healthy tissues collected for The Cancer Genome Atlas (TCGA). L1HS is overexpressed in most of the ...


Effect Of Bmp Treatment On Periostin Gene Expression In Pre-Osteoblastic Mc3t3-E1 Mouse Cells, Vincent Lee Khang May 2018

Effect Of Bmp Treatment On Periostin Gene Expression In Pre-Osteoblastic Mc3t3-E1 Mouse Cells, Vincent Lee Khang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Periostin is a secreted, extracellular matrix (ECM) protein widely expressed within collagen-rich fibrous connective tissues of the body including the periodontal ligament (PDL), bone, skin, heart, and cornea. Periostin has been shown to serve many important regulatory functions including cell adhesion, cell motility, wound healing and of particular importance to the dental field, differentiation of osteoblasts. The deletion of periostin compromises osteoblast attachment to bone matrix and induces a reduction in mineralization and expression of bone markers, including type I collagen, osteocalcin, osteopontin and alkaline phosphatase. Periostin has also been shown to play a significant role in collagen fibrillogenesis by ...


Digging Biomechanics In Geomyoid Rodents, Alexis Moore Crisp May 2018

Digging Biomechanics In Geomyoid Rodents, Alexis Moore Crisp

UNLV Theses, Dissertations, Professional Papers, and Capstones

Subterranean digging behaviors provide opportunities for protection, access to prey, and predator avoidance for a diverse array of vertebrates, yet studies of the biomechanics of burrowing have been limited by the technical challenges of measuring kinetics and kinematics of animals moving within a substrate. Prior studies of burrowing have recorded a single axis of x-ray video and/or force. However, empirical observations show that burrowing is not restricted to a single axis or plane. I describe a new system called a ‘tunnel-tube’ for measuring 3D reaction force during burrowing. This tunnel-tube has two separate tubes, one ‘entry tube’ that has ...


Prevalence Of Cariogenic Microbial Flora Among Scardovia Wiggsiae-Positive And Negative Patients, Amy Tam May 2018

Prevalence Of Cariogenic Microbial Flora Among Scardovia Wiggsiae-Positive And Negative Patients, Amy Tam

UNLV Theses, Dissertations, Professional Papers, and Capstones

The formation of dental caries (cavities) is a complex, multi-dimensional process that necessarily involves many risk factors – including the acquisition and colonization of cariogenic oral bacteria. The most frequently associated oral pathogens are the acid-producing and acid-tolerant oral streptococcus species, such as Streptococcus mutans (S. mutans or SM). Many studies have established and confirmed the critical role of the formation of biofilm in the virulence of S. mutans, and the critical role this may play in determining the balance of the oral microbiome towards health or disease.

More recent efforts have discovered a novel cariogenic pathogen, Scardovia wiggsiae (S. wiggsiae ...


The Caspase Cascade During Hibernation In The Golden-Mantled Ground Squirrel, Spermophilus Lateralis, Michael David Treat May 2018

The Caspase Cascade During Hibernation In The Golden-Mantled Ground Squirrel, Spermophilus Lateralis, Michael David Treat

UNLV Theses, Dissertations, Professional Papers, and Capstones

In several human pathologies like heart attack, stroke, neurodegenerative diseases, and autoimmune disorders, widespread cell death, or apoptosis, is a major cause of organ dysfunction and death. Hibernating golden-mantled ground squirrels, Spermophilus lateralis, experience numerous conditions during the winter that are known to be pro-apoptotic in other mammal systems (e.g. extreme hypothermia, ischemia and reperfusion, acidosis, increased reactive oxygen species, bone and muscle disuse). However, studies suggest that hibernators may invoke a protective phenotype to limit widespread cell damage and loss during the hibernation season. Could regulating apoptosis provide protection against the harmful conditions experienced during the hibernation season ...


Screening For The Novel Cariogenic Pathogen Scardovia Wiggsiae Among Orthodontic Patients, Adam Whiteley May 2018

Screening For The Novel Cariogenic Pathogen Scardovia Wiggsiae Among Orthodontic Patients, Adam Whiteley

UNLV Theses, Dissertations, Professional Papers, and Capstones

Screening for the Novel Cariogenic Pathogen Scardovia wiggsiae among Orthodontic Patients

by

Adam Whiteley

Dr. Karl Kingsley, Examination Committee Chair Professor of Biomedical Sciences University of Nevada, Las Vegas School of Dental Medicine

The recent discovery of a novel cariogenic pathogen Scardovia wiggsiae has led many scientists and oral health researchers to re-evaluate and re-examine existing saliva repositories to determine the prevalence among patient populations. Recent efforts at this institution have used existing saliva samples to determine the prevalence among both adults and pediatric patients. These studies have revealed this organism may be found in approximately one-quarter of all samples ...


An Analysis Of The Spatial, Temporal, And Functional Role Of Key Proteins In The Drosophila Melanogaster Salivary Gland During Exocrine Secretion, Kathryn Lantz Dec 2017

An Analysis Of The Spatial, Temporal, And Functional Role Of Key Proteins In The Drosophila Melanogaster Salivary Gland During Exocrine Secretion, Kathryn Lantz

UNLV Theses, Dissertations, Professional Papers, and Capstones

For over 60 years, the larval salivary gland of Drosophila melanogaster has been the ultimate model for elucidating how steroid hormones trigger genome-wide changes in gene expression in a specific target tissue. Because of the unusual interphase chromosomes of the salivary gland, the regions of the genome that are being induced by the steroid/receptor complex actually form puffs that are easily visible in compound microscopy. Despite the importance of this system, little has been elucidated over the years regarding how the hormone exposure actually changes the physiological activity of this secretory system. The work presented in this dissertation makes ...


A Potential Solution To A Poopy Problem: Bile Salt Analogs As Prophylactics Against Clostridium Difficile Infection, Jacqueline Renee Phan Dec 2017

A Potential Solution To A Poopy Problem: Bile Salt Analogs As Prophylactics Against Clostridium Difficile Infection, Jacqueline Renee Phan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Clostridium difficile infection (CDI) is a major cause of antibiotic-associated diarrhea. In 2011, over 500,000 patients were diagnosed with CDI in the United States and over 29,000 people died of CDI-related complications. With an average of $35,000 to treat a single case of inpatient CDI, cost burden to the healthcare system can reach up to $3.2 billion annually. As both hospital- and community-acquired CDI incidences rise due to the emergence of hypervirulent strains and CDI reoccurrences of up to 25%, standard treatments are rendered less effective and new methods of prevention are critical.

CDI is caused ...


Factors Influencing Induction Of Desiccation Tolerance In Bryophytes: Redefining Fundamental Aspects Of The Organism’S Relationship With The Environment In Xeric Habitats, Joshua Lee Greenwood May 2017

Factors Influencing Induction Of Desiccation Tolerance In Bryophytes: Redefining Fundamental Aspects Of The Organism’S Relationship With The Environment In Xeric Habitats, Joshua Lee Greenwood

UNLV Theses, Dissertations, Professional Papers, and Capstones

If one wishes to understand the ecological role, range, habitat preferences, selective pressures, reproduction, response to climate change, and the potential for survival under climactic change, range expansion and range contraction for species and populations of bryophytes, an understanding of their survival of the desiccated state, is essential. In order to further our understanding of desiccation tolerance in mosses, three projects were undertaken. The first of these investigated the nature of desiccation tolerance in mosses, specifically if desiccation tolerance can be induced; thereby providing a desiccation tolerant phenotype in a moss species generally considered desiccation sensitive (Physcomitrella patens, the model ...


Gene Expression Profiling In The Larval Fat Body Of Desiccation Selected Drosophila Melanogaster, Adriana Michelle Charles May 2017

Gene Expression Profiling In The Larval Fat Body Of Desiccation Selected Drosophila Melanogaster, Adriana Michelle Charles

UNLV Theses, Dissertations, Professional Papers, and Capstones

Drosophila melanogaster selected for resistance to desiccation (no food or water) display slower development and a higher body mass compared to fed controls due to an extended third larval instar. I hypothesize that desiccation selected D. melanogaster larvae will have a different gene expression profile compared to fed controls. Separate populations of D. melanogaster were subjected to desiccation (no food or water), starvation (no food) until 80-85% mortality, for 75 generations. mRNA from the larval fat body was collected at 88 hours, 96 hours, 112 hours and 120 hours post-hatching. Four replicate samples were used for each condition and time ...


Differential Cbct Analysis Of Collum Angles In Maxillary And Mandibular Anterior Teeth In Patients With Different Malocclusions, Erin Shane Wan Ma Dec 2016

Differential Cbct Analysis Of Collum Angles In Maxillary And Mandibular Anterior Teeth In Patients With Different Malocclusions, Erin Shane Wan Ma

UNLV Theses, Dissertations, Professional Papers, and Capstones

Background: The collum angle is an angular measurement of the difference between the longitudinal axis of the crown and the longitudinal axis of the root. The aim of this study was to determine the mean collum angles for all maxillary and mandibular anterior teeth. In addition, the collum angles of different molar and skeletal classifications were compared for each anterior tooth.

Methods: Based on patient records obtained from the University of Nevada, Las Vegas Department of Orthodontics and Dentofacial Orthopedics, 326 CBCT scans were selected and divided into four molar and skeletal classifications. The patients were divided into Class I ...


The Role Of Mfd In Stationary-Phase Oxidative Damage Repair In Bacillus Subtilis, Katelyn E. Porter Aug 2016

The Role Of Mfd In Stationary-Phase Oxidative Damage Repair In Bacillus Subtilis, Katelyn E. Porter

UNLV Theses, Dissertations, Professional Papers, and Capstones

Since the 1950’s it has been shown that bacterial cells accumulate mutations even in non- dividing conditions, but how this type of mutation occurs is still highly debated. In Bacillus subtilis, Mfd, a precursor of the nucleotide excision repair (NER) system, mediates the formation of mutations in stationary-phase or non-replicating cells. In growing cells, Mfd recruits repair when RNA polymerase is stalled during transcription; it then recruits proteins from NER to repair damage. Here, we examine the hypothesis that Mfd mediates the formation of mutations by interacting with cellular components that repair reactive oxygen species (ROS), a natural byproduct ...


Incomplete Denitrification In Thermus Species, Chrisabelle Mefferd Aug 2016

Incomplete Denitrification In Thermus Species, Chrisabelle Mefferd

UNLV Theses, Dissertations, Professional Papers, and Capstones

Members the bacterial genus Thermus have been shown to be incomplete denitrifiers, terminating with nitrite or nitrous oxide (N2O). However, the ability to carry out denitrification and the evolution of nitrogen oxide reductase genes in Thermus remains poorly understood. This study tests the hypothesis that incomplete denitrification is common in Thermus and seeks to uncover patterns in the evolution of denitrification pathways in Thermus. Denitrification capacity was determined in a collection of 25 strains representing ten species of Thermus and phylogenetic analysis was performed to determine whether denitrification genes evolved horizontally in Thermus. No strains in this study reduced nitrate ...


Physiology And Genetics Of Starvation-Selected Drosophila Melanogaster, Christopher Michael Hardy May 2016

Physiology And Genetics Of Starvation-Selected Drosophila Melanogaster, Christopher Michael Hardy

UNLV Theses, Dissertations, Professional Papers, and Capstones

In nature, organisms have evolved to survive in stressful environments. This has driven organisms to adopt a wide range of unique adaptations. Investigating the mechanistic basis of these adaptations is an important tool for discovery that has led to major advances in science and medicine.

We study how organisms survive life without food, or starvational stress. Environmental stressors have shaped the quantity and quality of food sources across the globe. This has led to vast differences in the ability of some organisms to tolerate starvation over others. Many researchers have used Drosophila melanogaster as a model to study global patterns ...


A Bioinformatics Approach To Addressing The Responses Of Rice Aleurone Cells To Hormones Abscisic Acid And Gibberellic Acid, Kenneth Arthur Watanabe May 2016

A Bioinformatics Approach To Addressing The Responses Of Rice Aleurone Cells To Hormones Abscisic Acid And Gibberellic Acid, Kenneth Arthur Watanabe

UNLV Theses, Dissertations, Professional Papers, and Capstones

The hormone abscisic acid (ABA) is biosynthesized by higher plants in response to various abiotic stresses such as drought and antagonizes the growth and germination-promoting hormone gibberellic acid (GA). The seed is a model system for studying desiccation tolerance and germination. The thin layer of cells surrounding the seed, the aleurone layer, plays a direct role in seed germination and an indirect role in desiccation tolerance. The goal of my research is to address the molecular mechanism underlying the responses of rice aleurone cells to ABA and GA, by taking a genomics approach. An accurate and complete annotation of the ...


Assessing The Importance Of Nurse Plant Associations To The Growth Of Pre-~Reproductive Yucca Brevifolia, Eric James Chameroy Dec 2015

Assessing The Importance Of Nurse Plant Associations To The Growth Of Pre-~Reproductive Yucca Brevifolia, Eric James Chameroy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Facilitation and competition among plant species, in addition to abiotic factors, play an important role in determining plant community structure in arid and semi-arid environments. I conducted a study in Dry Lake Valley, Lincoln County, Nevada, USA to investigate the importance of nurse plant associations to pre-reproductive Yucca brevifolia (Joshua tree). Dry Lake Valley lies within a transition desert between the Mojave and Great Basin Deserts with ecotonal plant communities consisting of species representative of both deserts. A vegetation survey described the communities in which this study was conducted as a Y. brevifolia woodland dominated by an understory of Ephedra ...


Scardovia Wiggsiae Prevalence In Orthodontic Patients, Brandon Joseph Streiff Dec 2015

Scardovia Wiggsiae Prevalence In Orthodontic Patients, Brandon Joseph Streiff

UNLV Theses, Dissertations, Professional Papers, and Capstones

Dental caries has mainly been associated with Streptococcus, Lactobacillus, Actinomyces and Veillonella species. But in recent salivary studies a new cariogenic pathogen, has been identified. This new bacteria, Scardovia wiggsiae (SW), is currently being tested within the UNLV School of Dental Medicine patient population. Although these current studies are being conducted to study its prevalence in both pediatric and adult populations, it has not been evaluated among patients with an altered oral environment as seen in patients with orthodontic appliances. Fixed orthodontic appliances increase the difficulty of removing daily plaque on and in between the teeth with standard oral hygiene ...


Paenibacillus Larvae Spore Germination And American Foulbrood Disease Development In Honey Bee Larvae, Israel Alvarado Aug 2015

Paenibacillus Larvae Spore Germination And American Foulbrood Disease Development In Honey Bee Larvae, Israel Alvarado

UNLV Theses, Dissertations, Professional Papers, and Capstones

Honey bee (Apis mellifera) pollination plays an important role in meeting our agricultural needs, yet we are incapable of completely preventing a decline in bee health, partially due to bacterial diseases. American Foulbrood (AFB), a bacterial disease of honey bee larvae, is particularly troublesome because the infectious agent is the bacterial spore of Paenibacillus larvae. Bacterial spores are resistant to extreme temperatures, unaffected by antibiotics, withstand exposure to disinfectants, and can remain dormant for years until they can revert back to vegetative cells.

Our research investigated P. larvae spore germination at the functional and pathogen-host level. We have found that ...


Cultivation-Dependent Analysis Of Microorganisms Associated With Various Hydraulic Fracturing Fluids, Anthony Harrington Aug 2015

Cultivation-Dependent Analysis Of Microorganisms Associated With Various Hydraulic Fracturing Fluids, Anthony Harrington

UNLV Theses, Dissertations, Professional Papers, and Capstones

The overarching goal of this study is to gain more insight to the microbial interactions associated with hydraulic fracturing by studying the culturable microorganisms present in various types of hydraulic fracturing fluids. Extraction of natural gas and other unconventional resources using hydraulic fracturing has increased in the last decade and very few studies have been conducted on the microorganisms associated with the various water types used in the process. From the very few published studies, the only cultivation-dependent method used involved determining the most probable number (MPN) of various metabolic groups, however the researchers failed to ask more in-depth questions ...


Decontamination Protocols For Watercraft And Wildland Firefighting Equipment In Preventing The Spread Of Invasive Quagga (Dreissena Rostriformis Bugensis) And Zebra (Dreissena Polymorpha) Mussels, Ashlie Watters Dec 2014

Decontamination Protocols For Watercraft And Wildland Firefighting Equipment In Preventing The Spread Of Invasive Quagga (Dreissena Rostriformis Bugensis) And Zebra (Dreissena Polymorpha) Mussels, Ashlie Watters

UNLV Theses, Dissertations, Professional Papers, and Capstones

Quagga and zebra mussels (Dreissena rostriformis bugensis and Dreissena polymorpha) are two invasive species introduced via ballast water discharged by large oceanic cargo ships to the North American Great Lakes in the late 1980s. Once established, the mussels spread quickly. In January 2007, D. rostriformis bugensis was discovered in Lake Mead, NV-AZ, and in that same year, mussels were confirmed further south on the Colorado River in Lakes Mojave and Havasu. Dreissenids clog water intake pipes, water filtration systems, and electric generating plants. The mussels also ruin boat motors, damage recreational equipment, and once established in the reservoir, routine maintenance ...


Characterization Of Metal-Reducing Microorganisms In Walker Lake: A Terminal Saline Desert Lake, Memona Khan Oct 2014

Characterization Of Metal-Reducing Microorganisms In Walker Lake: A Terminal Saline Desert Lake, Memona Khan

Honors College Theses

Metal-reducing microorganisms are increasingly being recognized as an essential component of aquatic microbial ecosystems involved in decomposition of organic matter. Alkaliphilic microbial reduction from alkaline lakes is a little studied field and one particular ecosystem, Walker Lake, presents the opportunity to investigate alkaliphilic metal reducers in their native ecological setting. Walker lake is a terminal, saline, desert lake with pH 9.4, Walker Lake samples of surface and deep sediments and water column samples from 0, 10, 5, 15, 17.5, 19 m depths were cultured by serial dilution in synthetic Walker Lake medium and supplemented separately with Hydrous Ferric ...


Mars-Relevant Phosphate Minerals And Implications For Martian Habitability, Christopher Adcock Aug 2014

Mars-Relevant Phosphate Minerals And Implications For Martian Habitability, Christopher Adcock

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation is comprised of three studies focused on martian phosphate availability, with an introductory chapter introducing and linking the three studies. Chapter two is on the subject of merrillite synthesis. Merrillite is an extraterrestrial Ca-phosphate mineral similar to the mineral whitlockite and is found as a dominant primary phosphate mineral in martian meteorites. The chapter includes methods of whitlockite and merrillite synthesis as well as a detailed characterization of the produced minerals and a mechanism by which charge balance can be maintained when merrillite is synthesized through dehydrogenation of whitlockite.

Chapter three presents the results of kinetic and thermodynamic ...


Survival, Growth, And Settlement Of Dreissena Rostriformis Bugensis Veligers In Low And High Calcium Waters, Emma Ruhmann Aug 2014

Survival, Growth, And Settlement Of Dreissena Rostriformis Bugensis Veligers In Low And High Calcium Waters, Emma Ruhmann

UNLV Theses, Dissertations, Professional Papers, and Capstones

Populations ofDreissena rostriformis bugensis(quagga mussels) have continued to spread throughout the western United States since their discovery in the Boulder Basin of Lake Mead, NV-AZ in early 2007. Today, quagga mussel specific research is still lacking and the physicochemical characteristics of aquatic systems required by quagga mussels to successfully establish is not fully understood. This includes an absence of research in aquatic environments in the western United States and on quagga mussel veligers (larval stage). Calcium is considered the defining factor for determining if a lake or river is suitable for quagga mussel establishment. The minimum calcium threshold for ...


Life History Tradeoffs And The Costs Of Reproduction In Arizona Bark Scorpions (Centruroides Sculpturatus), Michael Marie Webber May 2014

Life History Tradeoffs And The Costs Of Reproduction In Arizona Bark Scorpions (Centruroides Sculpturatus), Michael Marie Webber

UNLV Theses, Dissertations, Professional Papers, and Capstones

Tradeoffs in life history evolution result from conflicts in the time and energy that can be simultaneously invested in activities such as growth, reproduction, and survival. Reproduction is an energetically costly activity for organisms, and is known to elicit alterations in the daily activity patterns of individuals. I investigated reproductive tradeoffs in the Arizona Bark Scorpion,Centruroides sculpturatus. To better understand the nature of tradeoffs in this species, I examined the influence of reproductive state on the predatory efficiency and thermal preference of reproductive females. Further, I examined the influence of reproductive activities (i.e. gestation) on the ability of ...


The Grass Shrimp, Palaemonetes, Pugio: Hypoxic Influences On Embryonic Development, Christensen C. Javier May 2014

The Grass Shrimp, Palaemonetes, Pugio: Hypoxic Influences On Embryonic Development, Christensen C. Javier

UNLV Theses, Dissertations, Professional Papers, and Capstones

Grass shrimp,Palaemonetes pugio, can survive in brackish waters and estuarine ecosystems despite the frequent oscillations and fluctuations in salinity, temperature and oxygen. AdultP. pugiohave the ability to osmoregulate (Romney and Reiber 2011), change cardiac parameters to tolerate temperatures (not yet published, Mika and Reiber) and oxyregulate (Guadagnoli and Reiber 2013). Manipulation of cardiac parameters allows for these methods of regulation. However, cardiac contraction and internal convection of oxygen do not occur until later stages of embryonic development. Studies focused on these morphological and physiological advantages may provide further understanding of the regulatory mechanisms within grass shrimp embryos, larvae and ...


Understanding How Honey Bee Flight And Senescence Are Connected Through Oxidative Stress., Joseph Margotta May 2014

Understanding How Honey Bee Flight And Senescence Are Connected Through Oxidative Stress., Joseph Margotta

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goal of this dissertation was to exploit the tractability of the honey bee (Apis mellifera) to understand how the physiological and cellular mechanisms that determine the onset and duration of senescence are shaped by behavioral development and behavioral intensity. These data reveal how behavior can damage cells and consequently limit lifespan. The honey bee represents the ideal model to address these factors because age, behavior, functional senescence, and lifespan are easily manipulated independently of each other while in its natural environment. I determined if there was a cause-effect relationship between honey bee flight and oxidative stress by comparing damage ...