Digital Commons Network^™

Electric Field Controlled Strain Induced Switching Of Magnetization Of Galfenol Nanomagnets In Magneto-Electrically Coupled Multiferroic Stack, Hasnain Ahmad

Theses and Dissertations

The ability to control the bi-stable magnetization states of shape anisotropic single domain nanomagnets has enormous potential for spawning non-volatile and energy-efficient computing and signal processing systems. One of the most energy efficient switching methods is to adopt a system of a 2-phase multiferroic nanomagnet, where a voltage applied on the piezoelectric layer generates a strain in it and the strain is elastically transferred to the magnetostrictive nanomagnet which rotates the magnetization states of the nanomagnet at room temperature via the converse magnet-electric effect. Recently, it has been demonstrated that the magnetization of a Co nanomagnet can be switched between …

Adducins Are Negative Regulators Of Migration And Invasion Of Normal Lung Epithelial Cells And Lung Cancer Cells, Parth Hitenbhai Amin, Parth Amin

Theses and Dissertations

Cell migration is an important component of many physiological and pathological processes such as tissue and organ morphogenesis during development, wound healing, inflammatory immune response, and tumor metastasis. The actin cytoskeleton is the basic engine driving cell migration. In the present study, we elucidate the role of an important actin interacting proteins, Adducins, in motility of normal lung epithelium and lung cancer cells. Adducins are the family of cytoskeleton protein capping the fast growing end and facilitating the bundling of actin filaments. Adducins are encoded by the three closely related genes namely alpha (ADD1), beta (ADD2) and gamma (ADD3) Adducin. …

Development Of The Student Perceptions Of Writing Feedback Scale, Sarah A. Marrs

Theses and Dissertations

Students’ perceptions of feedback can impact other writing constructs, such as motivation, self-efficacy, self-regulation, and achievement (Ekholm, Zumbrunn, & Conklin, 2015; Magno & Amarles, 2011; Zumbrunn, Marrs, & Mewborn, 2016; Zumbrunn, 2013). The goal of this study was to develop a valid and reliable instrument for measuring students’ perceptions of writing feedback. Evidence for validity and reliability were gathered throughout the development of the Student Perceptions of Writing Feedback (PoWF) Scale, a self-report questionnaire that asks students how they perceive feedback they get on their writing from their teachers. Items on the PoWF reflected the extant literature on students’ feedback …

Discriminative Stimulus Properties Of Endogenous Cannabinoid Degradative Enzyme Inhibitors, Robert Owens Ii

Theses and Dissertations

Inhibition of fatty acid amide hydrolase (FAAH) or monoacylglycerol lipase (MAGL), the chief degradative enzymes of N-arachidonoyl ethanolamine (anandamide; AEA) and 2-arachidonoylglycerol (2-AG), respectively, elicits no or partial substitution for Δ⁹-tetrahydrocannabinol (THC) in drug discrimination procedures. However, combined inhibition of both enzymes fully substitutes for THC, as well as produces a full constellation of cannabimimetic effects. Because no published report to date have investigated whether an inhibitor of endocannabinoid hydrolysis will serve as a discriminative stimulus, the purpose of this doctoral dissertation was to investigate whether C57BL/6J mice would learn to discriminate SA-57 (4-[2-(4-Chlorophenyl)ethyl]-1-piperidinecarboxylic acid 2-(methylamino)-2-oxoethyl ester), a …

Substrate Recognition And Mechanistic Studies Of Protein N-Terminal Methyltransferase 1, Yunfei Mao

Theses and Dissertations

The methylation at the α-N-terminal amines of proteins that start with a canonical motif X-P-K (X=A/P/S) has been a known modification for nearly four decades. In 2010, protein α-N-terminal methyltransferase 1 (NTMT1/NRMT1) was identified as the first enzyme responsible for this modification. NTMT2 was discovered as a second member belonging to this family, but it was reported as a mono-methylase. The identification of RCC1, retinoblastoma (Rb) protein, centromere protein-A/B (CENP-A/B), and DNA damaged-binding protein 2 (DDB2) as new NTMT1 substrates revealed NTMT1’s biological significance in mitosis, cell-cycle regulation, centromere formation, and damaged DNA repair, respectively. Although significant progress had been …

Irreversible Zinc Block Of The Swelling-Activated Chloride Current In Di Tnc1 Astrocytes, Noah Belkhayat

Theses and Dissertations

The swelling-activated chloride current, commonly referred to as ICl,swell, is an outwardly-rectifying anion current that plays an important role in cell volume regulation, among other capacities. Despite several decades of research, the molecular identity of the channel responsible for this chloride current remains controversial. Recent indications that key endogenous sulfhydryl groups are capable of modifying the current led us to assess the effects of several divalent cations, including zinc, on ICl,swell. Zinc is known to tightly associate with sulfhydryl groups such as in zinc finger proteins. We found that extracellular zinc irreversibly inhibited ICl,swell at a site downstream in the …

A Weighted Gene Co-Expression Network Analysis For Streptococcus Sanguinis Microarray Experiments, Erik C. Dvergsten

Theses and Dissertations

Streptococcus sanguinis is a gram-positive, non-motile bacterium native to human mouths. It is the primary cause of endocarditis and is also responsible for tooth decay. Two-component systems (TCSs) are commonly found in bacteria. In response to environmental signals, TCSs may regulate the expression of virulence factor genes.

Gene co-expression networks are exploratory tools used to analyze system-level gene functionality. A gene co-expression network consists of gene expression profiles represented as nodes and gene connections, which occur if two genes are significantly co-expressed. An adjacency function transforms the similarity matrix containing co-expression similarities into the adjacency matrix containing connection strengths. Gene …

Probing Allosteric, Partial Inhibition Of Thrombin Using Novel Anticoagulants, Stephen S. Verespy Iii

Theses and Dissertations

Thrombin is the key protease that regulates hemostasis; the delicate balance between procoagulation and anticoagulation of blood. In clotting disorders, like deep vein thrombosis or pulmonary embolism, procoagulation is up-regulated, but propagation of clotting can be inhibited with drugs targeting the proteases involved, like thrombin. Such drugs however, have serious side effects (e.g., excessive bleeding) and some require monitoring during the course of treatment. The reason for these side effects is the mechanism by which the drugs’ act. The two major mechanisms are direct orthosteric and indirect allosteric inhibition, which will completely abolish the protease’s activity. Herein we sought an …

Provision Of Hospital-Based Palliative Care And The Impact On Organizational And Patient Outcomes, Marisa L. Roczen

Theses and Dissertations

Hospital-based palliative care services aim to streamline medical care for patients with chronic and potentially life-limiting illnesses by focusing on individual patient needs, efficient use of hospital resources, and providing guidance for patients, patients’ families and clinical providers toward making optimal decisions concerning a patient’s care. This study examined the nature of palliative care provision in U.S. hospitals and its impact on selected organizational and patient outcomes, including hospital costs, length of stay, in-hospital mortality, and transfer to hospice. Hospital costs and length of stay are viewed as important economic indicators. Specifically, lower hospital costs may increase a hospital’s profit …

High Affinity Block Of Icl,Swell By Thiol-Reactive Small Molecules, Sung H. Park

Theses and Dissertations

Ebselen (Ebs) is considered as a glutathione peroxidase (GPx) mimetic and primarily thought to function by scavenging intracellular reactive oxygen species (ROS). Previous to our work, Deng et al. (2010a) demonstrated complete block of I_Cl,swell with 15 microM Ebs following endothelin-1 (ET-1) induced activation of the current in cardiomyocytes. This block was presumed to take effect mainly via the quenching of ROS. Nonetheless, our work with DI TNC1 astrocytes strongly emphasizes that Ebs might function by an alternative mechanism based on its kinetic profile in blocking I_Cl,swell. Our experiments showed that 45 nM Ebs can fully block …

The Consequences Of Alcohol Mixed With Energy Drink (Amed) Use In College Students With Attention-Deficit/Hyperactivity Disorder (Adhd), Brooke A. Green

Theses and Dissertations

College students with ADHD, but especially those who consume alcohol, may be at jeopardy for experiencing negative educational and occupational outcomes, problematic substance use, criminal offending, and sexual victimization. Alcohol mixed with energy drink (AmED) use is widespread across college campuses and associated with many of these same problematic outcomes. The risk of experiencing these consequences for college students with ADHD may be exacerbated by AmED use given its unique relationship, above and beyond alcohol use, with these variables. This study sought to examine relationships among GPA, lost work performance, hazardous alcohol use, illicit substance use, criminal offending, and sexual …

Evaluating The Pennebaker Paradigm With Bereaved Emerging Adults: Applications Of Text Analysis, Elizabeth A. Collison

Theses and Dissertations

Bereavement is an important research area as it can result in grief reactions that lead to serious psychological and health consequences, particularly for the at-risk group of emerging adults (Arnett, 2000; Balk, Walker, & Baker, 2010; Fisher, Murray, & Frazer, 1985; Stroebe, Schut, & Stroebe, 2007). Expressive writing is a well-researched intervention for trauma and adjustment, yet research repeatedly has revealed null results with the classic Pennebaker paradigm as a bereavement intervention (Stroebe et al., 2002; Stroebe, Schut, & Stroebe, 2006). It may be premature, however, to conclude expressive writing is ineffective for the bereaved due to limitations in extant …

Investigating The Mechanism Of The Compartmentalized Cbp (Creb-Binding Protein) Ubiquitin Ligase Activities, Oluwatoyin E. Akande

Theses and Dissertations

CBP (CREB Binding Protein) is global transcriptional co-activator and histone acetyltransferase. CBP is involved in the modulation of the transcription of many genes via histone acetylation at the promoter regions of the target genes. Also, non-histone proteins and transcription factors can be acetylated by CBP to promote their transcriptional activation. In addition to its transcription co-activator role, CBP is involved in many other pathological and physiological cellular processes such as cell growth and differentiation, cell transformation and development, response to stress, cell cycle regulation and apoptosis.

CBP and its paralogue p300, play double-edged roles in the regulation of p53, a …

Markerless Lung Tumor Trajectory Estimation From Rotating Cone Beam Computed Tomography Projections, Shufei Chen

Theses and Dissertations

Respiration introduces large tumor motion in the thoracic region which influences treatment outcome for lung cancer patients. Tumor motion management techniques require characterization of temporal tumor motions because tumor motion varies patient to patient, day to day and cycle to cycle. This work develops a markerless algorithm to estimate 3 dimensional (3D) lung-tumor trajectories on free breathing cone beam computed tomography (CBCT) projections, which are 2 dimensional (2D) sequential images rotating about an axis and are used to reconstruct 3D CBCT images.

A gold standard tumor trajectory is required to guide the algorithm development and estimate the tumor detection accuracy …

Student Engagement In Undergraduate Social Work Education Among “At-Risk” Students, Ananda Newmark

Theses and Dissertations

College student engagement is an important factor that contributes to student success. This study is one of the first to explore student engagement in undergraduate social work education by examining engagement levels among at-risk social work students. In this study, two types of at-risk student groups were studied: First Generation College Students (FGCS) and transfer students. A cross sectional research design was used. Secondary analysis was performed on data gathered by the National Survey of Student Engagement (NSSE) from five accredited, Bachelor of Social Work (BSW) programs in one southeast state. A sample of 135 BSW seniors were included in …

Involvement Of Signal Peptidase I In Streptococcus Sanguinis Biofilm Formation, Jessica Aynapudi

Theses and Dissertations

Biofilm accounts for 65%-80% of microbial infections in humans. Considerable evidence links biofilm formation to oral disease and consequently systemic infections. Eradication of biofilm-associated infections is important. Streptococcus sanguinis, a Gram-positive bacterium, is one of the most abundant species in oral biofilm. It contributes to biofilm development in oral cavities and is one of the recognized causes of infective endocarditis. To study and identify biofilm genes in S. sanguinis, biofilm formation of 51 mutants was compared with the wild type SK36 strain using crystal violet (CV) staining in a microtiter plate. Confocal laser scanning microscopy (CLSM) and image analysis was …

Versatile Synthesis Of Transition Metal Phosphides: Emerging Front-Runners For Affordable Catalysis, April C. Mattei

Theses and Dissertations

Transition metal phosphide materials have found themselves at the forefront of research revolving around energy applications. Due to the vast range of properties possessed by marginally different phase compositions, binary and ternary metal phosphides are utilized as catalysts, semi-conductors and magnetocaloric materials along with many others. These attractive properties, which are highly phase dependent, call for a versatile and cost effective synthesis route for various phosphide materials without sacrificing properties important at the nanoscale such as particle size and morphology.

The primary focus outlined in the work of this dissertation pertains to a versatile wet chemical synthesis capable of producing …

Upper Thermal Limits Differ Among Component Species In A Host-Parasitoid-Hyperparasitoid System, Kanchan A. Joshi

Theses and Dissertations

Among the predicted impacts associated with global climate change, warming is of special interest because the rates of physiological processes are temperature-dependent. Insects and other ectotherms are likely to be affected due to their limited ability to control body temperature. In this study, I measured the tolerance to extreme high temperatures, i.e., critical thermal maximum (CT_max), of component species in a tri-trophic system, including an herbivore (Manduca sexta), a primary larval parasitoid (Cotesia congregata) and a hyperparasitoid (genus Silochalcis). For wild insects, the parasitoid had the lowest CT_max, the hyperparasitoid had …

A Correlational Analysis Of Secondary Data For Factors Influencing Graduation From Adult Drug Court, David N. Masri

Theses and Dissertations

The proliferation of drug courts throughout the world over the last two decades presents an opportunity and a challenge. The drug court approach involves a combination of treatment and judicial supervision which is a diversion from incarceration and/or ‘traditional’ criminal justice supervision. Despite widespread study of drug courts, there is much that researchers still do not know and there is still controversy as to how and why drug courts work. This research study is an examination of secondary data from an urban, mid-Atlantic drug court to attempt to correlate factors that contribute to success (as defined by graduation) in drug …

Allosteric Effects Of G-Protein Coupled Receptor Heteromerization: Relevance To Psychosis, Jason W. Younkin

Theses and Dissertations

G-protein coupled receptors (GPCRs) implicated in disease are the predominant pharmaceutical targets. Growing evidence suggests that GPCRs form homo- and heteromeric complexes, resulting in allosteric functional changes. Ligands targeting one receptor can alter the function of the other receptor or receptors. Knowledge of these functional changes will provide unique opportunities to treat diseases. We examined two GPCR heteromers implicated in psychosis: mGlu2R-5HT2AR and D2R-5HT2AR. Using whole-cell patch clamp, we studied HEK-293 cells stably transfected with mGlu2R and 5HT2AR. Maximal heteromer formation allows inverse agonists to increase the G-protein activity of the opposite receptor, while sub-maximal heteromer formation does not. However, …

Exploring Visual Prevention: Developing Infographics As Effective Cervical Cancer Prevention For African American Women, Candace P. Parrish

Theses and Dissertations

The purpose of this dissertation is to explore the creation of a cervical cancer health prevention infographic, geared toward African American women ages 30 to 65, to be potentially used to raise health literacy and influence positive behaviors towards practicing prevention measures—ultimately preventing unnecessary deaths. This dissertation also produced a cervical cancer health prevention infographic prototype for African American Women ages 30 to 65 to be further tested and implemented within future health communication campaigns.

Cervical Cancer is both preventable and treatable (if diagnosed during early stages); therefore the amount of individuals dying from the cancer should be minimal. Still, …

Plant Functional Trait And Hyperspectral Reflectance Responses To Comp B Exposure: Efficacy Of Plants As Landmine Detectors, Paul V. Manley Ii

Theses and Dissertations

At least 110 million landmines have been planted since the 1970s in about 70 nations, many of which remain in place today. Some risk of detection may be mitigated using currently available remote sensing techniques when vegetation is present. My study focused on using plants as phytosensors to detect buried explosives. I exposed three species representing different functional types (Cyperus esculentus (sedge), Ulmus alata (tree), Vitis labrusca (vine)) to 500 mg kg^-1 of Composition B (Comp B; 60/40 mixture of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene (TNT)), a commonly used explosive mixture, and measured functional traits and reflectance over …

Celecoxib Enhances Sorafenib/Sildenafil Lethality In Cancer Cells And Reverts Platinum Chemotherapy Resistance, Timothy A. Webb

Theses and Dissertations

The present studies sought to determine whether the lethality of the drug combination [sorafenib + sildenafil] could be enhanced by the anti-inflammatory agent celecoxib, using ovarian cancer and other tumor cell lines as models. Also, in a dose dependent fashion celecoxib enhanced [sorafenib + sildenafil] lethality in multiple ovarian cancer cell lines. In a dose dependent fashion celecoxib enhanced the ability of [sorafenib + sildenafil] to reduce expression of multiple chaperone proteins in parallel with lower levels of the drug efflux pumps ABCB1 and ABCG2. Over-expression of GRP78 and HSP27 maintained pump expression in the presence of drugs. Cell killing …

Viewing Victorian Prisoners: Representations In The Illustrated Press, Painting, And Photography, Lauren Boasso

Theses and Dissertations

Victorian prisoners were increasingly out of sight due to the ending of public displays of punishment. Although punishment was hidden in the prison, prison life was a frequent subject for representation. In this dissertation, I examine the ways Victorian illustrated newspapers, paintings, and photographs mediated an encounter with prisoners during a time when the prison was closed to outsiders. Reports and images became a significant means by which many people learned about, and defined themselves in relation to, prisoners. Previous scholarship has focused on stereotypes of prisoners that defined them as the “criminal type,” but I argue prisoners were also …

Introducing Novel Combinatorial Targeted Therapies In Multiple Types Of Cancer, Mehrad Tavallai

Theses and Dissertations

The cancers of liver, colon and breast are amongst the top five most prevalent and most fatal worldwide. As the Raf/MEK/ERK pathway is frequently deregulated in hepatocellular carcinoma (HCC), sorafenib, a Raf kinase inhibitor, became the first systemic therapy approved for the treatment of patients with HCC. However, sorafenib only produced modest effects with low response rates in the clinic. Similarly, regorafenib, which was approved for the treatment of metastatic colorectal cancer (CRC), has had a poor response rate in the clinic. Since phosphodiesterase type 5 has been reported to be overexpressed in HCC and CRC, we hypothesized that sildenafil, …

Jamaican Revolts In British Press And Politics, 1760-1865, Thomas R. Day

Theses and Dissertations

This research examines the changes over time in British Newspaper reports covering the Jamaican rebellions of 1760, 1832 and 1865. The uprisings: Tacky’s Rebellion, the Baptist War and the Morant Bay Rebellion respectively, represented three key moments in the history of race, slavery and the British Empire. Though all three rebellions have been studied, this work compares the three events as moments of crisis challenging the British public discourse on slavery, race and subjecthood as it related to the changing Atlantic Empire. British newspapers provided the most direct way in which popular readers and the growing literate public examined and …

Drug And Vaccine Development For Neisseria Gonorrhoeaea, Devin R. Cash

Theses and Dissertations

Neisseria gonorrhoeae, the causative agent of the STI gonorrhea, is not preventable by vaccination and is rapidly developing resistance to antibiotics. One important strategy for gonococcal survival in the host is iron acquisition in the face of nutritional immunity. To overcome iron limitation, the gonococcus expresses TonB dependent transporters (TdTs), outer membrane proteins that facilitate nutrient acquisition. Of the TdTs, the transferrin (Tf), lactoferrin (Lf), and hemoglobin (Hb) receptors hijack iron directly from host proteins, and studies have already shown that the Tf receptor is essential for the initiation of human infection. Given that the TdTs are virulence factors, …

Crescendo, Jeffery A. Pabotoy

Theses and Dissertations

Artist Statement

I have always found comfort and warmth in my family. When I am not with them, I find myself clinging to the objects they leave behind as a substitute in their absence. As I began to re-create these objects through paintings and ceramics, I realized that I was creating symbolic portraits of my family. These portraits are tangible family moments preserved in pigment and clay.

In recent years, my siblings were deployed to war and I began to represent them as various instruments. These instruments, both musical and tools of war, chronicle who they were and who they …

Expansion And Exclusion: A Case Study Of Gentrification In Church Hill, Kathryn S. Parkhurst

Theses and Dissertations

This thesis explores the gentrification process in Church Hill, one of the oldest neighborhoods in Richmond, Virginia. After World War II, Richmond residents knew Church Hill mostly for its crime rate and dilapidated housing. The white, middle-class flight to the suburbs left the remaining residents, mostly African American, to experience decades of disinvestment. Church Hill was considered a neighborhood to avoid for much of the late twentieth century. Yet, Church Hill is currently one of the most desired neighborhoods in Richmond, particularly for young professionals. This thesis seeks to explain the reasons why there has been such a dramatic change …

"Life Under Union Occupation: Elite Women In Richmond, April And May 1865", Amanda C. Tompkins

Theses and Dissertations

This paper crafts a narrative about how elite, white Richmond women experienced the fall and rebuilding of their city in April and May 1865. At first, the women feared the entrance of the occupying army because they believed the troops would treat them as enemies. However, the goal of the white occupiers was to restore order in the city. Even though they were initially saddened by the occupation, many women were surprised at the courtesy and respected afforded them by the Union troops. Black soldiers also made up the occupying army, and women struggled to submit to black authority. With …