Digital Commons Network^™

Development Of Reactions And Methods For Labeling Biomolecules In Cells, Enoch Agbesi Adogla

Theses and Dissertations

The complexity of cellular environments presents a challenge to efforts at studying and elucidating biomolecules in cells. Covalent ligation of biomolecules with fluorescent molecules that have a reactive functional group that can react with a complementary functional group on biomolecules is one way that has been utilized to study biomolecules. It enables visualization and tracking of ligation and transportation of molecules within the cell. However, the myriad of functional groups within the cell makes achieving selectivity difficult. To circumvent this problem, reactions that do not interfere with biology have been developed. These reactions, referred to as bioorthogonal reactions must be …

Investigating The Function Of Aintegumenta-Like6 (Ail6) In Arabidopsis Flower Development, Han Han

Theses and Dissertations

AINTEGUMENTA (ANT) and AINTEGUMENTA-LIKE6 (AIL6) encode related transcription factors with partially overlapping roles in floral organ development in the model plant Arabidopsis thaliana. ANT and AIL6 do not make equivalent contributions to these processes. Loss of ANT function by itself results in smaller flowers, demonstrating that the role of ANT in organ size control cannot be provided by AIL6. Loss of AIL6 function on its own has no phenotypic consequences indicating that all of its roles in flower development can be provided by ANT or some other genes. To further probe the function of AIL6 in flower development, we investigated …

The Development Of A Miniature Spatial Heterodyne Raman Spectrometer For Applications In Planetary Exploration And Other Extreme Environments, Patrick Doyle Barnett

Theses and Dissertations

Space exploration is arguably one of the most important endeavors our species has ever undertaken. Rapid advances in rocketry and robotics in recent years has allowed for positioning of complex scientific instruments on other planets with a precision that was previously thought impossible. This, along with the need for more sophisticated chemical measurements to achieve the goals of new, more ambitious missions and recent advances in in-situ and remote spectroscopic techniques, has led to a boom in the use of spectroscopic instruments for space exploration. However, future missions to the moons of Jupiter and Saturn, along with other planetary bodies …

High-Throughput Sequencing-Based Approaches For The Identification And Development Of Molecular Targets For Cancer Therapy, David Joel Oliver

Theses and Dissertations

Effective cancer treatment depends on the development of therapeutics that efficiently eliminate the disease without significant reduction to quality of life. Targeted therapeutics achieve these goals, but their long-term efficacy is limited by the ability of cancers to become resistant to these therapies over time. The identification of new therapeutic targets is crucial for the future of cancer treatment. In this work we present functional identification and characterization of novel targets for cancer therapy.

Loss-of-function screens are a well-founded approach for the functional identification of new therapeutic targets, and, in combination with high-throughput sequencing technology, can now be performed at …

Relationships Of Chronotype, Social Jetlag, Sleep, Physical Activity And Diet With Mood, Perceived Stress, Obesity, Blood Pressure And Prostate Cancer, Daria M. Mcmahon

Theses and Dissertations

Background: Chronotype, social jetlag, poor sleep, proinflammatory diet, and low physical activity have been associated with increased risk of chronic diseases: obesity, diabetes, cardiovascular disease, depression and cancer. Yet the relationships between these factors have not been extensively investigated in prospective studies.

Methods: Two studies were conducted. The first study followed 390 healthy men and women ages 21-35 for two years. Social jetlag [SJL] and sleep measures (total sleep time [TST], sleep onset latency [SOL], wake after sleep onset [WASO]), sleep efficiency [SE]), were derived from physical activity personal (armband) monitoring. The participants wore the armband for 4-10 …

Ndt And Shm Methods Of Damage Detection In Welded Structures, Saad Mohammed

Theses and Dissertations

There has been an increasing demand for Nondestructive Testing (NDT) and Structural Health Monitoring (SHM) techniques to continuously monitor during all processes of a structure to prevent catastrophic failure and reduce maintenance costs. NDT and SHM are inspection processes which form part of the quality assurance/quality control (QA/QC) scheme. Among NDT and SHM methods, ultrasonic and guided wave techniques are the most commonly and widely used in industry. Ultrasonic methods provide the advantage of accurately locating and dimensioning defects within structures. Most of these structures consist of welded joints because welding is an economical and efficient method for obtaining a …

Using Synthetic Lectins To Investigate Metastatic Potential In Colon Cancer, Erin E. Gatrone

Theses and Dissertations

Cancer is a disease that affects millions of people each year and it is well established that early diagnosis is a key factor towards improving survival rate, with that in mind there is a great need for better diagnostics. From the earliest onset of cancer, changes can be detected in the type and amount of carbohydrates expressed by the cancer cells, i.e., aberrant glycosylation. This process results in differing glycosylation patterns that can be used to detect cancer. Aberrant glycosylation can also greatly affect the potential of cancer cells to metastasize and can be used to stage the disease as …

The Relationship Between Peer-Self Concept And Academic Self-Concept In Elementary Students: A Person-Oriented Perspective, Catherine Jorgensen Snyder

Theses and Dissertations

Self-concept is one of the most researched constructs in educational psychology (Marsh, Xu, & Martin, 2012). It has been established that there are different domains of self-concept which fall into two main categories, academic and non-academic (Shavelson, Hubner, & Stanton, 1976). Unfortunately, little research has been conducted on the non-academic areas of self-concept and little is known about how social self-concept interrelates with academic self-concept. The focus of this study was to contribute to the research base by investigating the relationship between a facet of nonacademic self-concept, namely peer self-concept, and achievement self-concept among elementary students.

The current research utilized …

Semiparametric Estimation Methods For Complex Accelerated Failure Time Model, Yinding Wang

Theses and Dissertations

The proportional hazards (PH) model and the accelerated failure time (AFT) model are the two most popular survival models in fitting the right-censored data. The AFT model is a useful alternative to the PH model, particularly when the PH assumption is not satisfied. Usually, the linear association is assumed with logarithm of survival time in the AFT model. However, the nonlinear association may exist in practice. The first project aims to handle the nonlinear component in the AFT model, which is called the semiparametric additive partial accelerated failure time (AP-AFT) model. Two estimation methods based on the rank-smooth method and …

Contextualizing Multilayered Sexual Subjectivities Of Heterosexual Black Female Undergraduate Students At A Predominantly White Institution In The South, Amarachi Rossana Anakaraonye

Theses and Dissertations

This study uses an intersectional theoretical framework to examine Black college women’s sexual health by focusing on how they engage in sexual decision making within their social contexts. This qualitative study analyzed 20 individual in-depth interviews of Black female undergraduate students, ages 18-22, who attend a predominantly white institution (PWI) in the Southeastern United States. The themes that emerged from qualitative data analysis include Black female undergraduate students’ perceptions of the sexual culture of their campus and the protective strategies they employ to navigate the sexual culture in order to achieve and/or maintain physical, emotional, and social well-being. Key findings …

Interest Detection In Image, Video And Multiple Videos: Model And Applications, Yuewei Lin

Theses and Dissertations

Interest detection is detecting an object, event, or process that draws attention. In this dissertation, we focus on interest detection in images, video and multiple videos. Interest detection in an image or a video is closely related to visual attention. However, the interest detection in multiple videos needs to consider all the videos as a whole rather than considering the attention in each single video independently.

Visual attention is an important mechanism of human vision. The computational model of visual attention has recently attracted a lot of interest in the computer vision community mainly because it helps find the objects …

A Phenomenological Analysis Of Social Justice/Injustice On The Lives Of African-American High School Males, Michael R. Harris

Theses and Dissertations

The purpose of this study is to analyze what high school African-American males perceive as significant influences that directly impact their academic achievement while attending a predominantly White suburban high school. This qualitative research study will utilize semi-structured case interviews to collect and analyze data gathered from among a criteria-based subgroup of African-American high school males. An examination of archival data such as student course selections, a review of high school Carnegie units earned and attempted, the availability of support resources and interventions, as well discipline and attendance reports will each provide evidence of the probable obstacles impacting the achievement …

Development Of Protein-Polymer Core-Shell Nanoparticles (Ppcs-Nps) As Efficient Vehicles To Deliver Therapeutic Agents Across Blood Brain Barrier (Bbb), Napat Tandikul

Theses and Dissertations

Blood Brain Barrier (BBB) plays a main role as selective barrier which controls and limits access of chemicals, molecules and therapeutic agents from blood to brain. The BBB endothelial cells are connected by Tight Junctions (TJs) which close intracellular spaces between the endothelial cells and block the free diffusion of substances, therefore many potential drugs for treating human brain diseases cannot reach the brain in sufficient concentration. Recently, many studies have thrown an interest in development of nanoparticles for delivering drugs and imaging agents across BBB. Our research group has developed protein-polymer core-shell nanoparticles (PPCS-NPs) which demonstrate great potential for …

Some Extremal And Structural Problems In Graph Theory, Taylor Mitchell Short

Theses and Dissertations

This work considers three main topics. In Chapter 2, we deal with König-Egerváry graphs. We will give two new characterizations of König-Egerváry graphs as well as prove a related lower bound for the independence number of a graph. In Chapter 3, we study joint degree vectors (JDV). A problem arising from statistics is to determine the maximum number of non-zero elements of a JDV. We provide reasonable lower and upper bounds for this maximum number. Lastly, in Chapter 4 we study a problem in chemical graph theory. In particular, we characterize extremal cases for the number of maximal matchings in …

Influence Of Built Environment On Physical Activity Outcomes Among African Americans In Community-Based Obesity Intervention Studies, Amanda Sue Thomas

Theses and Dissertations

More than sixty-five percent of people in the U.S. are considered overweight or obese. African-Americans in the U.S. have a higher risk of obesity than any other racial group. One way to reduce this statistic is physical activity. Recreational green spaces (parks) can serve as an avenue to complete the 150 min/wk of recommended physical activity for adults by the ACSM. Data from SISTAS and HEALS interventions, that recruited overweight/obese African-Americans from Columbia and Florence, SC, was used to assess the association of recreational green space (parks) around a residence and physical activity. Physical activity measures of RAPA questionnaire (self-report), …

Iv Prenatal Nicotine Exposure Modulates Α6, Α7, And Α4Β2 Nicotinic Acetylcholinergic Receptor Subunit Expression In Male And Female Neonatal And Adolescent Rat Offspring: An Autoradiographical Analysis, Amanda Morgan

Theses and Dissertations

Maternal smoke exposure produces long-term adverse cognitive and behavioral outcomes in offspring, including an increased likelihood of attention problems (e.g., attention deficit hyperactivity disorder; ADHD) and drug abuse. Preclinical research shows that gestational exposure to nicotine, the primary psychoactive compound in tobacco smoke, influences the neurodevelopment of attention and reward neuronal circuits. This study investigated hypotheses about five brain regions, to determine if prenatal nicotine (PN) exposure altered expression of nicotinic acetylcholine receptors (nAChRs). A low dose, intravenous nicotine (IV) exposure method was used to administer nicotine (0.05 mg/kg/injection) or saline, 3x/day on gestational days 8–21 (Treatment). Brain tissue was …

Utilization Of Satellite-Derived Salinity For Enso Studies And Climate Indices, Caroline Mary Corbett

Theses and Dissertations

Conventionally, El Niño-Southern Oscillation (ENSO) is studied using sea surface temperature (SST) observations in the central and eastern equatorial Pacific Ocean. Recently, sea surface salinity (SSS) in the equatorial Pacific has been studied in relation to the phases of ENSO. Previously, SSS was observed in the equatorial Pacific using the Tropical Ocean Global Atmosphere (TOGA) / Tropical Atmosphere Ocean (TOA), the Argo float network, and Oceanic General Circulation Models (OGCM). The launch of NASA’s Aquarius Salinity Mission and ESA’s Soil Moisture Ocean Salinity (SMOS) opened a new era in which high resolution global near real-time SSS observations are readily available. …

Physical Property Control In Core/Shell Inorganic Nanostructures For Fluorescence And Magnetic Targeting Applications, Stephen K. Roberts

Theses and Dissertations

Nanomaterials show immense promise for the future in numerous areas of application. Properties that are unique from the bulk material and are tunable allow for innovation in material design. This thesis will focus on controlling the physical properties of core/shell nanostructures to enhance the utility of the materials.

The first focus is on the impact of different solvent mixtures during the shell growth phase of SILAR based core/shell quantum dot synthesis is studied. Gaining insight into the mechanism for SILAR growth of core/shell nanoparticles allows improved synthetic yields and precursor binding, providing enhanced control to synthesis of core/shell nanoparticles. The …

A Theoretical Study Of Polymer Based Drug Delivery Systems, Ebtisam Abdullatif Aldaais

Theses and Dissertations

Polymer nanostructured materials for drug delivery applications have witnessed tremendous progress in recent years due to their vast potential. One-end-grafted polymers can form grafted micelles with specific mechanical properties. Biological conditions can alter these properties resulting in the protection or release of drugs. Charged surfactants can also form micelles in an aqueous solution, which can also be manipulated through special conditions. On the micellar surface, self-organized polyelectrolytes can be stimulated to extend their attached ligands and thus increase the probability of binding to targeted receptors. This thesis focuses on modeling polymer-based drug delivery systems by studying the physical interactions between …

Understanding The Problem Solving Approaches Of Special Educators Through The Lens Of Adaptive Expertise, Serra T. De Arment

Theses and Dissertations

The purpose of this research was to investigate special educators’ problem solving approaches through the lens of adaptive expertise. An explanatory sequential mixed methods design was used with participants of varying experience levels and teaching contexts from one Mid-Atlantic state. Participants responded to a researcher-developed survey about their orientations to problem solving (N = 162), then a purposive sample completed semi-structured interviews (N = 8). Following survey measure refinement and validation, quantitative data were analyzed through descriptive statistics, z-scores, correlation, and chi-square test of independence. Subsequently, qualitative data were analyzed through iterative cycles of hypothesis and open coding. …

The Role Of N-Acetyl-L-Cysteine (Nac) As An Adjuvant To Opioid Treatment In Patients With Inadequately Controlled Chronic Neuropathic Pain, Thomas B. Moore

Theses and Dissertations

Introduction. While opioid medications are commonly prescribed for management of neuropathic pain (NP), long-term use has been associated with increased risk for overdose, drug interactions and addiction. New strategies are necessary to better manage chronic pain, thereby reducing need for opioid medications and their associated adverse consequences. N-acetyl-L-cysteine (NAC), an over-the-counter supplement, has shown promise in the treatment of psychiatric and addictive disorders. In addition, NAC has shown promise for reducing physiological signs of NP in laboratory rat models, prompting this study.

Purpose. The present study was an open-label clinical trial of NAC as an adjuvant to opioid treatment for …

Radioprotective Cerium Oxide Nanoparticles: Molecular Imaging Investigations Of Conps’ Pharmacokinetics, Efficacy, And Mechanisms Of Action, Philip R. Mcdonagh Iii

Theses and Dissertations

Cerium oxide nanoparticles (CONPs) are being investigated for several anti-oxidant applications in medicine. One of their most promising applications is as a radioprotective drug, an area of research in need due to the severe side effects from radiation therapy. In this work, the potential of CONPs as a radioprotective drug is examined using four criteria: favorable biodistribution/pharmacokinetics, low toxicity, ability to protect normal tissue from radiation damage, and lack of protection of tumor. The mechanisms of action of CONPs are also studied. Biodistribution was determined in radiolabeled CONPs with surface coatings including citrate, dextran T10-amine (DT10-NH₂), dextran T10-polyethylene …

Dynamic Regulation Of Mitochondrial Stat3 And Its Association With Cypd, Jeremy A. Meier

Theses and Dissertations

In recent years, a number of nuclear transcription factors have been shown to be present in the mitochondria where they have distinct roles in regulating mitochondrial function. Signal Transducer and Activator of Transcription 3 (STAT3), classically activated by the JAK family of receptor associated tyrosine kinases to drive nuclear gene expression, is one such transcription factor with a unique mitochondrial role. There, it has been shown to support oxidative phosphorylation, regulate mitochondrial-encoded transcripts, and be key for the transformation and growth of a number of different cancers. Despite its well-characterized functional importance at the level of the mitochondria, the mechanism …

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 …

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, …

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, …

Characterization Of Fibrin Matrix Incorporated Electrospun Polycaprolactone Scaffold, Cho Yi Wong

Theses and Dissertations

Specific objective: Guided tissue regeneration (GTR) aims to regenerate the lost attachment apparatus caused by periodontal disease through the use of a barrier membrane. For the GTR procedures to be successful, barrier membranes are required to be present at the surgical site for an extended period of time (weeks to months). Synthetic membranes have the advantage of prolonged presence in a wound site; however, they do not actively contribute to wound healing. Biologic membranes are recognized by the host tissue and participate in wound healing but have the disadvantage of early resorption. Therefore, the goal of this study is …

Vital Pulp Therapy Survivability Based On Radiographic Depth Of Caries, Aaron T. Schmick

Theses and Dissertations

Purpose: The purpose of this retrospective chart review was to determine if the survival of two methods of vital pulp therapy (VPT) were influenced by the pre-operative radiographic depth and location of caries. Methods: Electronic patient records (axiUm®) that contained the procedure codes D3120, Indirect Pulp Therapy (IPT), or D3220, Therapeutic Pulpotomy (TP), were queried. Qualifying charts’ pre-operative and post-operative radiographs were viewed in MiPACS® by two raters. Visit records were queried again to identify any other treatment failures. Results: A total of 568 primary molars met the eligibility criteria. There was a difference in survival depending upon the treatment …

Fabrication Of Multifunctional Nanostructured Porous Materials, Ahmed A. Farghaly

Theses and Dissertations

Nanostructured porous materials generally, and nanoporous noble metals specifically, have received considerable attention due to their superior chemical and physical properties over nanoparticles and bulk counterparts. This dissertation work aims to develop well-established strategies for the preparation of multifunctional nanostructured porous materials based on the combination of inorganic-chemistry, organic-chemistry and electrochemistry. The preparation strategies involved one or more of the following processes: sol-gel synthesis, co-electrodeposition, metal ions reduction, electropolymerization and dealloying or chemical etching. The study did not stop at the preparation limits but extended to investigate the reaction mechanism behind the formation of these multifunctional nanoporous structures in order …