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Molecular Mechanism Of Cyanobacteria Circadian Clock Oscillator And Effect Of Co Factors On Its Oscillation, Manpreet Kaur

Dissertations

The circadian rhythms arise as an adaptation to the environmental 24-hour day and night cycle due to Earth's rotation. These rhythms prepare organisms to align their internal biological activities and day to day behavior or events with the environmental change of the 24-hour day and night cycle. Circadian rhythms are found widely in all living kingdoms of life on Earth. Cyanobacteria are photosynthetic prokaryotes which first used to study these circadian rhythms. Among cyanobacterial species, Synechococcus elongatus PCC 7942 (henceforth, S. Elongatus) is the simplest organism with a durable and sturdy circadian clock and is study as a model organism. …

A Phenomenological Study On The Impact Of Servant Leadership For Establishing A Culture Of High Performance As Perceived By High School Principals, Darrick Rice

Dissertations

Purpose: The purpose of this phenomenological study was to explore and describe the perceived impact of Patterson’s (2003) 7 servant leadership constructs on high school principals in establishing a culture of high performance.

Methodology: The qualitative phenomenological study described the lived experiences of high school principals who lead schools that have implemented Patterson's (2003) 7 servant leadership constructs for establishing a culture of high performance in Los Angeles County, California. The researcher was a part of 8 peer researchers and 2 faculty advisors. The data collection included virtual face-to-face semi structured interviews using a protocol developed by the thematic team. …

A Management Strategy Evaluation Of The Impacts Of Interspecific Competition And Recreational Fishery Dynamics On Vermilion Snapper (Rhomboplites Aurorubens) In The Gulf Of Mexico, Megumi C. Oshima

Dissertations

In the Gulf of Mexico (GOM), Vermilion Snapper (Rhomboplites auroruben), are believed to compete with Red Snapper directly for prey and habitat. The two species share similar diets and have significant spatial overlap in the Gulf. Red Snapper are thought to be the dominate competitor, forcing Vermilion Snapper to feed on less nutritious prey when local resources are depleted. In addition to ecological pressures, GOM Vermilion Snapper support substantial commercial and recreational fisheries. Over the past decade, recreational landings have steadily increased, reaching a historical high in 2018. One cause may be stricter regulations for similar target species such as …

An Examination Of The Influence Of Multi-Scale Processes And Connectivity On The Population And Assemblage Dynamics Of Headwater Fishes, Josh P. Hubbell

Dissertations

Typified by their branching pattern, headwaters are numerically abundant as the density of these habitats increases with increasing distance from the base of a dendritic river system. Connectivity among headwaters is complex, resulting in the spatial isolation of populations. Headwater specialists have evolved a suite of traits that permit these species to permanently reside within these habitats. The spatial configuration and connectivity of headwaters has repercussions for metapopulations and meta-assemblages. I investigated how multi-scale processes and connectivity influenced the patch occupancy, coexistence, movement ecology, population structure, and gene flow of headwater specialists. In chapter two, I used occupancy modeling to …

Interactions Of The Nlrp3 Inflammasome Complex, Nyasha Makoni

Dissertations

The innate immune system is the first line of defense in response to invasion by pathogens. One of the major pathways in the innate immune system involves a three-protein complex known as the NLRP3 inflammasome. This complex comprises of NLRP3, ASC, and procaspase-1. In response to stimuli, the inflammasome assembles to activate caspase-1 which subsequently facilitates production of interleukin-1β (IL-1β), an inflammatory cytokine. The NLRP3 inflammasome has been implicated in a variety of inflammatory disorders including Alzheimer’s disease (AD). Amyloid beta (Aβ) is the protein that causes AD and Aβ deposits in the brain activate microglia resulting in chronic inflammation. …

Evaluation Of The Genetic And Structural Variations Of Camel Hemoglobin, Amanat Ali

Dissertations

The single-humped Arabian camel (Camelus dromedarius) thrives in the hot arid Arabian desert. Many unique adaptations permit it to accomplish this. Camel erythrocytes or red blood cells (RBCs) have a peculiar elliptical shape and are amenable to large variations in physical conditions resulting from dehydration and rehydration cycles. The oxygen transport protein hemoglobin is found abundantly in RBCs and is also believed to behave differently in camels. While several physiological and biochemical studies have been performed on camel hemoglobin, very little is known about genetic and structural adaptions in this protein. The camel genome harbors several unique variations …

Identification And Characterization Of Novel Genes And Genetic Interactions That Influence Iba Metabolism, Vanessica Jawahir

Dissertations

Indole-3-butyric acid (IBA) is an endogenous storage auxin important for maintaining appropriate indole-3-acetic acid (IAA) levels that influences primary root elongation and lateral root development. IBA is metabolized into free IAA in the peroxisome in a multistep process similar to fatty acid β-oxidation. Although many components specific to IBA metabolism and peroxisome function have been identified, our understanding is incomplete. I sought to identify novel components of IBA metabolism or peroxisome function by conducting a forward genetic screen for Arabidopsis thaliana plants with enhanced resistance to IBA. I identified Long chain acyl-CoA synthetase 4 (LACS4) as a novel gene functioning …

Enrichment Of Ontologies Using Machine Learning And Summarization, Hao Liu

Dissertations

Biomedical ontologies are structured knowledge systems in biomedicine. They play a major role in enabling precise communications in support of healthcare applications, e.g., Electronic Healthcare Records (EHR) systems. Biomedical ontologies are used in many different contexts to facilitate information and knowledge management. The most widely used clinical ontology is the SNOMED CT. Placing a new concept into its proper position in an ontology is a fundamental task in its lifecycle of curation and enrichment.

A large biomedical ontology, which typically consists of many tens of thousands of concepts and relationships, can be viewed as a complex network with concepts as …

Mathematical Models And Tools To Understand Coupled Circadian Oscillations And Limit Cycling Systems, Guangyuan Liao

Dissertations

The circadian rhythm refers to an internal body process that regulates many body processes including the sleep-wake cycle, digestion and hormone release. The ability of a circadian system to entrain to the 24-hour light-dark cycle is one of the most important properties. There are several scenarios in which circadian oscillators do not directly receive light-dark forcing. Instead they are part of hierarchical systems in which, as \peripheral" oscillators, they are periodically forced by other \central" circadian oscillators that do directly receive light input. Such dynamics are modeled as hierarchical coupled limit cycle systems. Those models usually have a large population, …

Efficient Approximations For Stationary Single-Channel Calcium Nanodomains, Yinbo Chen

Dissertations

Mathematical and computational modeling plays an important role in the study of local Ca2+ signals underlying many fundamental physiological processes such as synaptic neurotransmitter release and myocyte contraction. Closed-form approximations describing steady-state distribution of Ca2+ in the vicinity of an open Ca2+ channel have proved particularly useful for the qualitative modeling of local Ca2+ signals. This dissertation presents several simple and efficient approximants for the equilibrium Ca2+ concentration near a point source in the presence of a mobile Ca2+ buffer, which achieve great accuracy over a wide range of model parameters. Such approximations provide an efficient method for estimating Ca2+ …

Genetic Population Structure And Microbiome Of German Cockroaches In Urban Environments, Xueyang Fan

Dissertations

Pests of human habitats may harbor and disperse pathogens that cause human disease. One such pest is the German cockroach (Blattella germanica), which is known to harbor numerous pathogens, including Klebsiella and Pseudomonas. The aim of this study is to reveal the importance of the German cockroach as a potential vector of human medically important diseases. To do so, this study investigates German cockroach population structure and their associated bacterial microbiome in urban residential environments. Ninety German cockroaches are collected from three residential apartment buildings in three New Jersey cities. Samples are caught by glue traps and stored at -20°C. …

1,4-Dioxane Biodegradation In Propanotrophs: Molecular Foundations And Implications For Environmental Remediation, Li Fei

Dissertations

1,4-Dioxane (dioxane) has emerged with an escalating concern given its human carcinogenicity and widespread occurrence in groundwater. Bioremediation is promising as an effective and cost-efficient treatment alternative for in situ or ex situ cleanup of dioxane and co-existing pollutants in the field. Soluble di-iron monooxygenases (SDIMOs) are reputed for their essential roles in initiating the cleavage of dioxane and other pollutants. In this doctoral dissertation, molecular foundations for SDIMOs-mediated dioxane biodegradation are untangled to promote the development and implication of site-specific bioremediation and natural attenuation strategies. This dissertation focused on propanotrophic bacteria given their pivotal roles in dioxane metabolism and …

Investigating The Combined Effects Of Whole Body Vibration And Vestibular Stimulation On Spasticity And Dystonia In Cerebral Palsy, Peter A. Michael

Dissertations

This study identifies and addresses three voids and potential shortcomings associated with the classification, assessment and management of Cerebral Palsy (CP). These concerns should not undermine the significant advancement that has been made in this specific branch of rehabilitation, but addressing them is necessary. Cerebral Palsy is a group of motor impairments due to hypoxic-ischemic brain damage around the time of birth and very commonly manifests as excessive muscle tone and poor motor control. There are classifications within CP including spasticity and dystonia.

First, a level of discrepancy is present in the classification of CP between the clinical and research …

Microglia Induced Neuroinflammation Through The Nlrp3 Inflammasome Following Blast Traumatic Brain Injury, Daniel Younger

Dissertations

The incidence of traumatic brain injury (TBI) among military personnel have been steadily increasing with modern conflicts. A recent RAND report estimated 320,000 service members, totaling 20% of deployed forces, suffer from TBI. However, of this population roughly 60% have not seen a medical professional specifically for TBI. Unlike the civilian population, the primary cause of TBI for active-duty military personnel is blast exposure. Blasts now account for over 70% of all US military casualties in operation Iraqi Freedom (OIF) and Operation enduring freedom (OEF) and are the major cause of TBI. Among many pathological mechanisms associated with blast TBI, …

The Assessment Of Co2 Exposures, Workload Demands, And Musculoskeletal Disorder Risk On Heart Rate For Select Craft Brewery Job Tasks, David L. Huizen

Dissertations

Americans have embraced craft beer, and the ensuing demand has resulted in an ever-increasing number of craft breweries opening over the past 20 years. Craft brewers are generally small employers and, as such, lack the resources necessary to address the safety and health of their employees adequately. Brewers face many safety and health hazards in their work environment. These hazards include exposures to carbon dioxide (CO₂), workload demand, and MSD risk. It is essential to evaluate these hazards in craft breweries as they handle carbon dioxide (CO₂) differently than large breweries by having the CO_{2 …}

Comparison Of Retention Rates Between Traditional On-Ground And Online Biology Laboratory Courses In The Community College Setting, Megan Davis Winborne

Dissertations

Community colleges provide vital educational resources to students across the nation. Online learning has become an integral part of the course offerings for community colleges. With regards to online learning, there is a lack of empirical evidence and research focused on community college offered biology laboratories, particularly concerning retention rates of these students. Means, Toyama, Murphy, and Bakia. (2013) found that even though there are copious amounts of studies dedicated to evaluation of evidence-based practices in online learning formats, many of them neglected to review retention rates associated with online educational courses.

The purpose of this study was to determine …

The Role Of Homologous Cyclin B’S In The Cell Cycle And, In Their Absence, The Effect On Zebrafish Early Development, Tetiana Petrachkova

Dissertations

Regulation of cell division is essential for normal embryo development. The Cyclins and their Cyclin-dependent kinases are key regulators controlling this process. In this thesis, I examine the role of cyclin B1 and cyclin B2 in zebrafish development. It is thought that both Cyclins are necessary for a cell to progress past the G2/M checkpoint into mitosis. First, I show that zygotic Cyclin B1 is essential for normal cell cycle progression, but not for cells to enter mitosis. Lack of zygotic Cyclin B1 in the early arrest mutant specter, which carries a nonsense mutation in the cyclin B1 gene, …

The Role Of Plasticity In Bumble Bee Responses To Environmental Variability, Matthew Austin

Dissertations

An aim of contemporary biology is elucidating the causes and consequences of phenotypic plasticity. Here, I approach this aim by exploring the eco-evolutionary dynamics of phenotypic plasticity and environmental variability in bumble bees (Apidae: Bombus), a congeneric clade of eusocial pollinating insects. Throughout their evolution, bumble bees have encountered spatiotemporal variability imposed by dynamic floral environments. Today, bumble bees additionally encounter spatiotemporal variability imposed by anthropogenic environmental change. In this dissertation, I explore how phenotypic plasticity affects how successfully bumble bees respond to environmental variability imposed by anthropogenic global change (Chapters 1 and 2) and their floral resources (Chapters …

A Strategic Plan To Thread Genomics Competencies Into Undergraduate Curriculum, Holly Mathis

Dissertations

Problem: Genomics in undergraduate nursing education has experienced slow adoption in the United States. Various approaches have been proposed but do not address barriers to successful implementation.

Methods: A strategic plan was developed to increase the amount of genetics and genomic content in the curriculum of an undergraduate nursing program. A gap analysis was performed on the curriculum revealing a paucity of content. A SWOT analysis informed the strategic plan, which included a faculty education program using the ANA/ISONG’s Essentials of Genetic and Genomic Nursing: Competencies, Curricula Guidelines and Outcome Indicators (2^nd ed.) (2009) as a foundation.

Results: Faculty …

Modeling Single Microtubules As A Colloidal System To Measure The Harmonic Interactions Between Tubulin Dimers In Bovine Brain Derived Versus Cancer Cell Derived Microtubules, Arooj Aslam

Dissertations

The local properties of tubulin dimers dictate the properties of the larger microtubule assembly. In order to elucidate this connection, tubulin-tubulin interactions are be modeled as harmonic interactions to map the stiffness matrix along the length of the microtubule. The strength of the interactions are measured by imaging and tracking the movement of segments along the microtubule over time, and then performing a fourier transform to extract the natural vibrational frequencies. Using this method the first ever reported experimental phonon spectrum of the microtubule is reported. This method can also be applied to other biological materials, and opens new doors …

Modulation Of Cerebellar Purkinje Cell Activity With Low Intensity Electric And Ultrasound Stimulation, Ahmet S. Asan

Dissertations

Non-invasive brain stimulation (NIBS) techniques garner significant interest due to their potential to offer instantaneous and region-specific treatments to neurological disorders. The cerebellum is one of the target sites for NIBS methods due to its central role in motor and cognitive functions. Among several modulation techniques, transcranial electric stimulations (tEs), in particular, transcranial direct and alternating current stimulations (tDCs/tACs), and low intensity focused ultrasound stimulation (LIFUS) show encouraging outcomes in clinical applications. tDCs and tACs are favored due to their low cost and accessibility while LIFUS offers high spatial resolution and deeper penetration without affecting the surrounding structures. In order …

Plant Evolution And Urbanization: Quantifying The Effects Of Natural Selection In Shaping Shepherd’S Purse (Capsella Bursa-Pastoris) Populations In New York City, Rebecca Panko

Dissertations

The aim of this study is to quantify the effects of natural selection in shaping Capsella bursa-pastoris populations along an urban-rural gradient in New York City.

A reciprocal transplant experiment with 168 lab-germinated C. bursa-pastoris seedlings from both urban and rural populations are grown in eight paired home and away sites distributed throughout the New York metropolitan area. Sites are visited approximately thirteen times to record plant fitness. There is evidence for local adaptation of urban populations: urban plants have longer reproductive durations and produce more seed pods in urban environments. These findings suggest that urban plants are better adapted …

Nanocarbon Modification Of Membranes For Enhanced Water Desalination And Water Treatment, Worawit Intrchom

Dissertations

Water scarcity is foreseen to be one of the great global issues in the coming decades. The challenges are not only in providing water supply to cope with the growing public demand, but recovering clean water to natural resources. Clean water supply, from brackish and seawater is attractive. Membrane distillation (MD) is an emerging thermal membrane-based process that has been used for desalination and other pollutant separations from water. MD can be operated at low temperature, so low-grade energy sources are a good alternative heat source for MD. High salt rejection and low membrane fouling also make MD interesting for …

Data Assimilation For Conductance-Based Neuronal Models, Matthew Moye

Dissertations

This dissertation illustrates the use of data assimilation algorithms to estimate unobserved variables and unknown parameters of conductance-based neuronal models. Modern data assimilation (DA) techniques are widely used in climate science and weather prediction, but have only recently begun to be applied in neuroscience. The two main classes of DA techniques are sequential methods and variational methods. Throughout this work, twin experiments, where the data is synthetically generated from output of the model, are used to validate use of these techniques for conductance-based models observing only the voltage trace. In Chapter 1, these techniques are described in detail and the …

The Roles Of Inhibition In C. Elegans Locomotion, Lan Deng

Dissertations

Inhibition plays important roles in modulating neural activities at different levels from small synapses to brain regions, and different systems from sensory to motor. To achieve translocation, locomotor systems produce alternation of antagonist muscles, including axial posture and limb movement and alternation. In the nematode C. elegans, a cross-inhibition circuit, involving excitatory cholinergic and inhibitory GABAergic motoneurons, is believed to generate the dorsoventral alternation of body-wall muscles that supports backward undulatory locomotion. This dissertation challenges this prevalent hypothesis, delves into studying different roles of inhibition, and depicts the expression pattern and functional role of ionotropic GABAA receptor, UNC-49, in motoneurons …

Antibiotic Resistant Bacteria, Antibiotic Resistance Genes And Potential Drivers In The Aquatic Environments, Shuo Shen

Dissertations

As antibiotic resistance genes in aquatic environment have been increasing across the world, affecting water quality and public health, many studies documented concentrations of antibiotic resistance genes and some studies discussed their potential drivers. However, systematic and quantitative reviews that link antibiotic resistance genes (ARGs) to anthropogenic and environmental factors are limited. Nevertheless, this information will be important for developing regulation policy on controlling antibiotic use and therefore reducing potential risks to antibiotic resistance. I conducted meta-analysis of ARGs concentration at a global scale using Bayesian inference to explore climatic and socio-economic factors as drivers. I found local-scale climatic variables …

Chemoenzymatic Study Of Coa-Linked Rna In Bacteria, Krishna Sapkota

Dissertations

The ability of RNA to store genetic information and to catalyze biochemical transformations led to the speculation of the existence of RNA world before the evolution of contemporary ribonucleoprotein (RNP) world. Recent discovery of RNA molecules containing metabolic cofactors including coenzyme A and its various thioesters at their 5’ end further supported the RNA world hypothesis as these CoA-linked RNA molecules could be the molecular fossils with very ancient origin. As both RNA and Coenzyme A are believed to have co-existed since last universal common ancestor (LUCA) or even before, the CoA-RNA conjugates in current biology may reveal fundamental molecular …

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 …

The Ecology And Evolutionary History Of Two Musk Turtles In The Southeastern United States, Grover Brown

Dissertations

Turtles are among one of the most imperiled vertebrate groups on the planet with more than half of all species worldwide listed as threatened, endangered or extinct by the International Union of the Conservation of Nature. The Southeastern United States is a global biodiversity hotspot for turtles, and it likely represents the last area on the planet of both high diversity and high abundance of turtle species. In the past century, there has been an exponential increase in the number of publications on turtles in the United States and Canada, however a recent review of the literature suggests that this …

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 …