Digital Commons Network^™

A Study Of The Effect Of Harvesting On A Discrete System With Two Competing Species, Rebecca G. Clark

Theses and Dissertations

This is a study of the effect of harvesting on a system with two competing species. The system is a Ricker-type model that extends the work done by Luis, Elaydi, and Oliveira to include the effect of harvesting on the system. We look at the uniform bound of the system as well as the isoclines and perform a stability analysis of the equilibrium points. We also look at the effects of harvesting on the stability of the system by looking at the bifurcation of the system with respect to harvesting.

N-Methyl 4-Methyl Amphetamine N-Alkyl Chain Extension Differentially Affects Ion Flux At The Human Dopamine And Norepinephrine Transporters, Alan C. Harris Jr.

Theses and Dissertations

Amphetamine (AMPH) and its derivatives embody a remarkable breadth of pharmacology. These molecules exert their effects, both therapeutic and pathological, at the human monoamine transporters, which tune synaptic dynamics by evacuating monoamine neuromodulators from the synapse subsequent to neuronal impulses. These transporters are electrogenic, and the transporter-mediated current can be correlated to a surrogate measure of the change in membrane voltage: Ca⁺⁺ currents from co-transfected L-type Ca⁺⁺ channels. The present work makes use of this assay, with which it is possible to derive pharmacodynamic metrics from both substrates and inhibitors. This work presents data on a heretofore-unstudied class …

Pharmacological Implications Of Adenosine 2a Receptor- Dopamine Type 2 Receptor Heteromerization, Candice N. Hatcher-Solis

Theses and Dissertations

G protein-coupled receptors (GPCRs) are heptahelical, transmembrane proteins that mediate a plethora of physiological functions by binding ligands and releasing G proteins that interact with downstream effectors. GPCRs signal as monomers, complexes of the same receptor subtype (homomers), or complexes of different receptor subtypes (heteromers). Recently, heteromeric GPCR complexes have become attractive targets for drug development since they exhibit distinct signaling and cell-specific localization from their homomeric counterparts. Yet, the effect of heteromerization on the pharmacology of many GPCR homomers remains unknown. Therefore, we have undertaken the task to examine the effect of heteromerization on G_s signaling through the …

In-House Fabrication Of Multi-Sized Polystyrene Microcarriers For Neural Stem Cell Expansion, Jessica Forrester

Theses and Dissertations

The clinical demand for neural stem cells drives the need for a reproducible method used to generate a large quantity of well-characterized cells to support regenerative therapies. Microcarriers are currently being used as a scaffold for stem cell culture to aid in this expansion process because they provide a larger surface area while also requiring fewer cell passages compared to monolayer culture. The main objective of this project was to investigate how human neural stem cell attachment, proliferation, and multipotency would respond to three-dimensional (3D) culture using peptide-coated microcarriers of varying diameters. In this study, multi-sized polystyrene microcarriers were fabricated …

Fabricating Superhydrophobic And Superoleophobic Surfaces With Multiscale Roughness Using Airbrush And Electrospray, Karam N. Almilaji

Theses and Dissertations

Examples of superhydrophobic surfaces found in nature such as self-cleaning property of lotus leaf and walking on water ability of water strider have led to an extensive investigation in this area over the past few decades. When a water droplet rests on a textured surface, it may either form a liquid-solid-vapor composite interface by which the liquid droplet partially sits on air pockets or it may wet the surface in which the water replaces the trapped air depending on the surface roughness and the surface chemistry. Super water repellent surfaces have numerous applications in our daily life such as drag …

Response Of Soil Microbial Communities To Saltwater Intrusion In Tidal Freshwater Wetlands, Chansotheary Dang

Theses and Dissertations

Saltwater intrusion due to global change is expected to have a detrimental effect on the biogeochemistry of tidal freshwater wetlands. Of particular concern is that fact that salinization can alter the role of these ecosystems in the global carbon cycling by causing shifts in microbial metabolism that alter greenhouse gas emissions and increase carbon mineralization rates. However, our understanding of how wetland microbial community dynamics will respond to saltwater intrusion is limited. To address this knowledge gap and increase our understanding of how microbial communities in tidal freshwater wetlands change over time (1, 3, 12, and 49 weeks) under elevated …

Gender Nonconforming, Transgender, And Transsexual Patient Navigation Of The American Health Care System: Locating A Primary Care Provider, Justin M. Vinneau

Theses and Dissertations

This study explores the experiences of gender nonconforming (GNC), transgender, and transsexual (trans) people in the search for a primary care provider in the United States. The current body of literature on transgender health often discusses HIV rates, substance use, mental health/suicide, and few studies have studies primary care seeking behaviors; this study seeks to provide new insight into the primary care (pcp) seeking behaviors of GNC and trans people. The primary theoretical perspectives utilized in this study were West and Zimmerman’s (1987) “Doing Gender” and the Health Beliefs Mode (Ayers et al., 2007; Connor and Norman, 2005; Green and …

Predictors Of Caffeine-Related Withdrawal Symptoms In College Freshmen, David J. Pomm

Theses and Dissertations

While caffeine withdrawal has been well-characterized, research on caffeine intake and factors associated with withdrawal has been limited. The present study examined prevalence rates of caffeine use and identified psychosocial factors associated with having caffeine withdrawal headaches (CWH). Participants were N = 1,989 college freshmen who participated in the 2011 Spit for Science project. Caffeine use was reported by 80% of the sample. Females were more likely than males to consume caffeine, and soda was the primary source of caffeine for both genders. As hypothesized, daily caffeine users were more likely to report CWH than non-daily users. When multivariable analyses …

Continuous Stationary Phase Gradients For Planar And Column Chromatography, Veeren Dewoolkar

Theses and Dissertations

Surfaces that exhibit a gradual change in their chemical and/or physical properties are termed as surface gradients. Based on the changes in properties they are classified either as physical or chemical gradients. Chemical gradients show variations in properties like polarity, charge, functionality concentration and have found potential applications in fields of biology, physics, biosensing, catalysis and separation science. In this dissertation, surface gradients have been prepared using controlled rate infusion (CRI).

CRI is a simple method in which a surface gradient is formed by carrying out the infusion of organoalkoxysilane in a time-dependent fashion using a set infusion rate. Depending …

Evaluation Of Redox Potential As A Novel Biomarker Of Oxidative Stress, Inflammatory Response, And Shock Using Nanoporous Gold Electrodes, Matthew C. Ellenberg

Theses and Dissertations

EVALUATION OF REDOX POTENTIAL AS A NOVEL BIOMARKER OF OXIDATIVE STRESS, INFLAMMATORY RESPONSE, AND SHOCK USING NANOPOROUS GOLD ELECTRODES

Background: Redox potential is a chemical species’ affinity for electrons. Increased oxidant concentration is associated with disease1,2, yet there is not a way to measure systemic redox status.3 Redox potentiometry uses metal electrodes that do not work in blood because protein molecules adhere on the metal surface, blocking electron exchange.

Methods: Nanoporous gold electrodes have large surface areas that allowed electron exchange to continue in blood.4 Redox potential was measured in blood with ascorbic acid, in cardiac bypass patients and pigs …

From Seed To Sky: Impacts Of Explosive Compounds On Vegetation Across Spatial And Developmental Scales, Stephen M. Via

Theses and Dissertations

Explosive compounds are broadly distributed across the globe as a result of nearly two centuries of munitions use in warfare and military activities. Two explosive compounds have seen disproportionate use; RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) and TNT (2-methyl- 1,3,5-trinitrobenzene), being the most commonly found explosives in the environment. The effects of explosives on biota have been studied in great detail; however, there is a general lack of understanding with regard to broader ecological impacts of these contaminants. My dissertation objective was to follow the impacts of explosive compounds on vegetation across scales. Impacts on vegetation at the species scale alter community composition via …

The Molecular And Mechanical Mechanisms Of The Age-Associated Increase In The Severity Of Experimental Ventilator Induced Lung Injury, Joseph Ames Herbert

Theses and Dissertations

Abstract

Background

The majority of patients requiring mechanical ventilation are over the age of 65 and advanced age is known to increase the severity of ventilator-induced lung injury (VILI) and mortality. However, the mechanisms which predispose aging ventilator patients to increased mortality rates are not fully understood.

Pulmonary edema is a hallmark of VILI and the severity of edema increases with age. Ventilation with conservative fluid management decreases mortality rates in acute respiratory distress (ARDS) patients, but has not been investigated in VILI. We hypothesized that age-associated increases in pulmonary edema promote age-related increases in ventilator-associated mortality. Endoplasmic reticulum (ER) …

Host Densities And Parasitism Rates In A Forest Defoliator Across A Rural-Urban Landscape, Abigail J. Nelson

Theses and Dissertations

Fall cankerworm (FCW) outbreaks have recently increased in frequency and intensity in the mid-Atlantic region of the United States, especially around cities of Charlotte, NC and Richmond, VA. This study evaluated the effects of two landscape features associated with urbanization, impervious surface and forest cover, on population patterns of FCW and its parasitoids across eastern Virginia. Forest cover was positively related to parasitism rates while impervious surface was positively related to FCW abundance, suggesting that FCW outbreaks may be amplified in urban areas. FCW abundance declined over the two-year period of this study, but parasitism rate increased at most sites. …

One Of Us, Farrah T. Al Sulaiman

Theses and Dissertations

With this thesis, I reflect on my identity as a Saudi American. I look at how nonverbal communication through gesture and artifact presents the potential for both communication breakdowns, as well as shared understanding. From the lens of Saudi culture, I consider how gender relations and intra-national tribal factions play a role in the division of society, which my work seeks to overcome, at both the national and global levels. My exhibit, One of Us, interrogates one of the most controversial gestures in contemporary society: veiling. As I discuss the notion of camouflage, I review the types of veils available …

Effects Of Antidepressants On Human Mesenchymal Stem Cell Differentiation On Clinically Relevant Titanium Surfaces, Nancy B. Ayad

Theses and Dissertations

Selective Serotonin Reuptake Inhibitors (SSRIs) are the most frequently prescribed class of drugs worldwide and are implemented in the treatment of depression and other psychiatric disorders. SSRIs relieve depressive symptoms by modulating levels of the neurotransmitter serotonin in the brain. SSRIs block the function of the serotonin transporter, thereby increasing concentrations of extracellular serotonin. However, serotonin levels in the neurons of the brain only account for 5% while the remaining 95% is present outside the brain. Serotonin receptors and transporter are located on bone resident cells (mesenchymal stem cells (MSCs)), osteoblasts and osteoclasts, and serotonergic activity is believed to affect …

Multimodal Communication, Idealization, And Relational Quality In College Students' Parental Relationships: A Model Of Partner Idealization In Ongoing Relationships, Erin M. Bryant, Artemio Ramirez Jr.

Human Communication and Theatre Faculty Research

This study tested the partner idealization component of the hyperpersonal perspective, and extended this perspective to the study of an ongoing relationship – college students and their parents. We proposed a model to encompass the cognitive and behavioral idealization mechanisms that past research identified as provoking positive relational outcomes. Results indicated that mediated communication frequency was positively related to both idealization and relational quality, and that idealization partially mediated the statistical relationship between mediated communication frequency and relational quality. Face-to-face communication frequency was inversely related to one indicator of idealization (positive affect thinking), but was not directly related to relational …

Meta-Mindfulness: A New Hope, Peter H. Huang

Publications

This Essay starts by tracing its humble origins to an earlier, related and unique law review article, namely, Tiger Cub Strikes Back: Memoirs of an Ex-Child Prodigy About Legal Education and Parenting. This Essay describes various professional responses to Tiger Cub Strikes Back, provides an update of some developments in research about parenting and legal education since Tiger Cub Strikes Back, and recounts a few personal stories about mindfulness and related to being an ex-child prodigy. This Essay then analyzes meta-mindfulness, defined as mindfulness about mindfulness. This Essay discusses how mindfulness about mindfulness can help facilitate the …

Quantitative Comparison Of A Nanoengineered Alumina Coated Cnt Arrays To Sio2 Coated Cnts And Solution Based Delivery System, Shree Aier

Maseeh Summer Undergraduate Research Experience

To meet the growing need for nanoengineered biocompatible materials to serve as drug delivery platforms, in this research, carbon nanotube arrays were fabricated by chemical vapor deposition, followed by an alumina coating by the high yielding, tightly controlled atomic layer deposition. This nanoengineered vertically aligned alumina nanowire array serves as a platform for delivering antigens, which act as cancer adjuvants. The physicochemical characteristics of the nanowires (NWs) can significantly influence the delivery of a biomolecule to immune cells. To investigate the material characteristics, the delivery efficiency of the antigen using NWs was quantitatively assessed by flow cytometry. Further, the mechanism …

Emerging Adaptive Architectures For Biomolecular Computation, Matthew Fleetwood

Maseeh Summer Undergraduate Research Experience

The goal of this work is to explore applications of reservoir computing in biomolecular computation. Reservoir computing is a unique model for representing a mapping from one instance in time to a specific output. A neural network of randomly connected neurons is linked with a single output neuron or multiple output neurons. The output neurons are capable of mapping inputs to desired outputs using adaptable algorithms. This framework is investigated by using the Python programming language and object oriented design and programming. Neurons are created in programs by bundling information like input data and attributes of the network, which utilize …

Genetic Essentialism In Family Law, Jennifer S. Hendricks

Publications

No abstract provided.

Law, Science, And The Injured Mind, Govind Persad

Publications

Even while we widely recognize legal liability for physical injury, we frequently discount mental, emotional, and psychological injury. We disfavor tort liability for emotional distress; we prohibit prisoners from suing for purely psychological injuries; and we tax the damages victims of emotional injury receive even while leaving damages for physical injury untaxed. This Article argues that neuroscientific, psychological, and technological advances challenge our traditional ideas about the set of injuries that are possible and that merit legal redress. The Article goes on to contend that, while these advances challenge our traditional ideas, they do not inevitably overturn traditional distinctions within …

Health Theater, Govind Persad

Publications

"Security theater" has been defined as an effort to "provide the feeling of security instead of the reality. " The concept of security theater has been discussed in both the popular press and academic literature, but has not yet entered health law. This project suggests that a parallel category of "health theater" picks out a set ofpractices in medical screening and health care delivery that provide a mere simulacrum ofprotection against medical risk, rather than providing genuine medical benefit. Part I summarizes some of the distinctive advantages and disadvantages of health and security theater. Like security theater, health theater frequently …

The Simulation Of Sound Signal Masking With Different Chaotic Oscillations And Its Circuit Application, Mehmet Nuri̇ Almali, Zi̇nnur Di̇ki̇ci̇

Turkish Journal of Electrical Engineering and Computer Sciences

The chaotic masking process on sound signals using the systems of Lorenz, Rössler, Sprott, Chen, and Arneodo chaotic oscillations are simulated with MATLAB/Simulink. The PID control method providing synchronization in the system is defined and the mean square errors between the times to reach synchronization and the input-output sound signals are compared for the system performance. The Sprott chaotic system is found to be the best synchronized system. Therefore, the application circuits are designed with respect to the Sprott chaotic system and its results are investigated in this study. It is seen that the system marked with the Sprott chaotic …

Fpga Implementations Of Scale-Invariant Models Of Neural Networks, Zeinulla Zhanabaev, Yeldos Kozhagulov, Dauren Zhexebay

Turkish Journal of Electrical Engineering and Computer Sciences

Integrated circuit implementations of new models of neural networks with scale-invariant properties are presented. The specifics of such models are necessary in analysis of discrete mappings containing fractional power. We suggest an algorithm for increasing the power of a physical value by using a field-programmable gate array (FPGA). Comparisons between FPGA implementations and numerical results are demonstrated.

Design And Analysis Of A Novel Uwb Bandpass Filter Using 3-D Em Simulation-Based Neural Network Model With Hsa, Sali̇h Demi̇rel, Cafer Uyanik

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a new systematic analysis and design of the ultrawide-band bandpass filter by using the 3-D electromagnetic simulation-based multilayer perceptron neural network (MLP NN) model of unit elements. This MLP NN model is utilized efficiently as a fast and accurate model within a harmony search algorithm (HSA) procedure to determine the resultant optimum microstrip structure geometry. Moreover, the validity and efficiency of the HSA is manifested by comparing it with those of the standard metaheuristics, which are genetic and particle swarm algorithms. The filter that shows the best performance is designed and realized. Measurements taken from the realized …

Discriminant-Based Bistability Analysis Of A Tmg-Induced Lac Operon Model Supported With Boundedness And Local Stability Results, Nesli̇han Avcu, Güleser Kalayci Demi̇r, Ferhan Pekergi̇n, Hakan Alyürük, Levent Çavaş, Cüneyt Güzeli̇ş

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents the results of a theoretical and numerical study on the analysis of bistable behavior of the most studied gene regulatory network, the lac operon, in terms of the model parameters. The boundedness of the state variables for the considered model are demonstrated, the parameter values providing the existence of the multiple equilibria and thus the bistable behavior are determined, and a local stability analysis of the equilibria is performed. The parameter region yielding the existence of multiple equilibria is determined in an algebraic way based on discriminants. The model given in the state equation form is defined …

A Simple Hybrid Method For Segmenting Vessel Structures In Retinal Fundus Images, Cemal Köse

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a simple, fast, and efficient hybrid segmentation method is presented for extracting vessel structures in retinal fundus images. Basically, this hybrid approach combines circular and naive Bayes classifiers to extract blood vessels in retinal fundus images. The circular method samples pixels along the enlarging circles centered at the current pixel and classifies the current pixel as vessel or nonvessel. An elimination technique is then employed to eliminate the nonvessel fragments from the processed image. The naive Bayes method as a supervised technique uses a very small set of features to segment retinal vessels in retinal images. The …

Behavior Characteristics Of A Cap-Resistor, Memcapacitor, And A Memristor From The Response Obtained Of Rc And Rl Electrical Circuits Described By Fractional Differential Equations, Jose Francisco Gomez Aguilar

Turkish Journal of Electrical Engineering and Computer Sciences

This paper provides an analysis of RC and RL electrical circuits described by a fractional difierential equation of Caputo type. The order considered is ${0 \textless \gamma }\le ${ 1}. The Laplace transform of the fractional derivative is used. To keep the dimensionality of the physical quantities, R, C, L, and an auxiliary parameter $\sigma $ are introduced, characterizing the existence of fractional components in the system. The relationship between $\gamma$ and $\sigma $ is reported. The response obtained from the fractional RC and RL circuits exhibits the characteristic behaviors of a cap-resistor, memcapacitor, and memristor, as well as charge-voltage …

A Facial Component-Based System For Emotion Classification, Elena Sönmez, Songül Albayrak

Turkish Journal of Electrical Engineering and Computer Sciences

Smart environments with ubiquitous computers are the next generation of information technology, which requires improved human--computer interfaces. That is, the computer of the future must be aware of the people in its environment; it must know their identities and must understand their moods. Despite the great effort made in the past decades, the development of a system capable of automatic facial emotion recognition is still rather difficult. In this paper, we challenge the benchmark algorithm on emotion classification of the Extended Cohn-Kanade (CK$+)$ database, and we present a facial component-based system for emotion classification, which beats the given benchmark performance: …

Application Of Kappa Statistics In Sequential Tests For Family-Based Design, Farid Rajabli

Turkish Journal of Electrical Engineering and Computer Sciences

Family-based designs are commonly used in genetic association studies to locate markers associated with diseases. It is a challenging task to collect a large enough sample size, perform a statistical test, and obtain the desired statistical power. The sequential probability ratio test (SPRT) was introduced to overcome the limited sample size problem. However, the drawback of SPRT is that, for the sake of accuracy, the test leaves many markers in a gray zone meaning ``no decision''. In this article, we propose a novel approach: a sequential probability ratio test `plus' (SPRT$+)$ to reduce the number of these gray zone markers. …