Digital Commons Network^™

Optical Method For High Magnification Imaging And Video Recording Of Live Cells At Sub-Micron Resolution, Jaime E. Romo Jr.

Theses and Dissertations

Optical microscopy, the most common technique for viewing living microorganisms, is limited in resolution by Abbe’s criterion. Recent microscopy techniques focus on circumnavigating the light diffraction limit by using different methods to obtain the topography of the sample. Systems like the AFM and SEM provide images with fields of view in the nanometer range with high resolvable detail, however these techniques are expensive, and limited in their ability to document live cells. The Dino-Lite digital microscope coupled with the Zeiss Axiovert 25 CFL microscope delivers a cost-effective method for recording live cells. Fields of view ranging from 8 microns to …

Wettability Of Nonwoven Polymeric Nanofiber Mats, Edgar Munoz

Theses and Dissertations

The wettability of heterogeneous materials has been attracting special interest by academia and industrial sector given the need to development self-cleaning Nonwoven nanofiber mats have demonstrated potential given its hydrophobicity granted by the ultimate structure of the system, small fiber diameter and small pores giving rise to effects such as the Cassie-Baxter. This thesis analyzed the wettability of a wide range of polymeric systems. Nanofiber mats were manufactured using the Forcespinning® technology. Samples were prepared at different polymeric concentrations and rotational speeds to alter fiber size; density of the mat was also altered to evaluate the effect of porosity on …

Knee Joint Internal Forces During Squat Jump Exercise, Ricardo Moreno

Theses and Dissertations

The purpose of this research is to investigate muscular ligament and joint contact forces produced during squat jump exercise. An inverse dynamics, two dimensional, leg model is used to describe the motion in the sagittal plane. The lower extremity model includes two bones, tibia and femur, tibio-femoral ligaments, and muscles such as quadriceps, hamstrings, and gastrocnemius. The ligaments are anatomically modeled as nonlinear strings, but the femoral condyle is modeled as a circle and the tibial plateau as a straight line. Experimental squat jump exercises are conducted to obtain the ground reaction forces, the angular accelerations, and centroid linear acceleration …

Development Of A Fundamental Autonomous Ground Vehicle Cruise Control Using Matlab And Simulink, Luis F. Martinez

Theses and Dissertations

This study presents and describes the development of a fully autonomous vehicle cruise control system covering the vehicle dynamics and control design needed to simulate such system. It encompasses obstacle avoidance, intelligent-and-optimal lane change as well as adaptive behavior. This study offers a comprehensive two-dimensional cruise control with three degrees of freedom and it is designed using active obstacle avoidance controllers. It also includes optimized fuzzy logic for optimal vehicle trajectory and an extensive array of control law methodology. The end work shows a complete simulation run using MATLAB and Simulink.

Using Machine Learning To Predict Student Achievement On The State Of Texas Assessment Of Academic Readiness Examination In Charter Schools, Christopher D. Gonzalez

Theses and Dissertations

The purpose of this study was to research and develop a way to use machine learning algorithms (MLAs) to predict student achievement on the State of Texas Assessment of Academic Readiness (STAAR), specifically in the charter school setting. Charter schools have the disadvantage of a constant influx in students, so providing historical student data in order to analyze trends proves difficult. This study expands on previous research done on students in secondary and post-secondary school and determining features that indicate success in these settings. The data used is from the district of IDEA Public Schools who focuses on providing education …

Syntheses And Characterization Of A New Cyano-Substituted Bis(Pyrazolyl)Borate And Its Thallium (I) Complex, Chris Acquah

Electronic Theses and Dissertations

Scorpionates are versatile and flexible ligands with a wide range of applications including catalysis, C-H bond activation, formation of new class of materials, and mimicking enzymatic reactions. This is as a result of its steric and electronic properties, and due to the relative ease with which the 3, and 5-positions of the pyrazole ring can be functionalized. In this work, we report the synthesis of a new class of scorpionate ligands known as cyanoscorpionates which can crosslink various metal centers. Thus, bis (4-cyano-3,5-diphenylpyrazolyl)borate Bp^Ph2,4CN was synthesized and fully characterized by ¹H NMR and FT-IR. Coordination of bis (4-cyano-3,5-diphenylpyrazolyl)borate …

Portrayal Of African Women In Nollywood Films Over A Five-Year Period: A Content Analysis Of Traits Applying The Stereotype Content Model, Olushola Aromona

Electronic Theses and Dissertations

Previous research shows that perceptions, attitudes, and beliefs are cultivated via media exposure. A content analysis of stereotypical traits in five Nollywood movies in a five-year span examines the prevalent portrayals of women in the Nigerian movie industry – Nollywood, and the effect of these portrayals on reinforcement of stereotypical norms and perpetuation of gender disparity. Cultivation and Objectification theories were the theoretical frameworks for this study. Findings revealed no significant change in the stereotypical portrayals of women in the past five years. From the movies analyzed, Nollywood movies appear to remain persistent in typically depicting women as unambitious domestic …

Pharmacokinetics, Tissue Distribution, Synergistic Activity, And Antitumor Activity Of Two Isomeric Flavones, Crystal L. Whitted

Electronic Theses and Dissertations

Flavonoids are polyphenolic secondary metabolites found in plants that have bioactive properties including antiviral, antioxidant, and anticancer. Two isomeric flavone were extracted from Gnaphalium elegans and Achyrocline bogotensis, plants used by the people from the Andean region of South America as remedies for cancer. 5,7-dihydroxy-3,6,8-trimethoxy-2-phenyl-4H-chromen-4-one (5, 7–dihydroxy- 3, 6, 8 trimethoxy flavone/ flavone A) and 3,5-dihydroxy-6,7,8-trimethoxy-2-phenyl-4H-chromen-4-one (3, 5–dihydroxy-6, 7, 8–trimethoxy flavone/ flavone B) have shown antineoplastic activity against colon cancer cell lines dependent upon their differentiation status. Pharmacokinetic studies reported herein were used to determine dosing for antitumor assays, as well as determine target tissue concentration. These included the …

Fishes As A Template For Reticulate Evolution: A Case Study Involving Catostomus In The Colorado River Basin Of Western North America, Max Russell Bangs

Graduate Theses and Dissertations

Hybridization is neither simplistic nor phylogenetically constrained, and post hoc introgression can have profound evolutionary effects. Most studies have focused on tractable model systems, rather than organisms with complicated phylogenetic histories. Finescale Sucker (genus Catostomus) in western North America is recognized as a paradigm of fish hybridization. Yet, its extent of historic and contemporary introgression is largely unstudied, an aspect that impedes the resolution of its phylogeny as a baseline for conservation. To explore reticulation in this group, I assayed variation of 20 Catostomus species across temporal and geographic scales by analyzing hundreds of samples and employing a combination of …

Multiscale Mechanics Of Bone: Examining The Influence Of Genetic Alterations, Brendyn James Miller

Theses and Dissertations

This MSc thesis investigates how genetic alterations involved in the synthesis of proteins or in the regulation of tissue remodeling affects the composition, structure and mechanics of bone at the multiscale levels. This was accomplished by performing two mouse model studies. In the first study, bone properties of TIMP-3 knock-out (Timp-3⁻ˊ⁻) mice were examined by performing mechanical testing, µCT analysis, and FTIR analysis. Results demonstrated that the mechanical integrity of the Timp-3⁻ˊ⁻ bone was compromised. Decreased values for the yield and ultimate load, stress capacity, and fracture toughness were observed in both the TIMP-3 deficient bones. These reductions in the …

Symptom Prevalence In A Cohort Of 147 Patients Improved With The Homoeopathic Medicine Ocimum Canum: A Multicenter, Open, Observational, Clinical Verification Study, Rajkumar Manchanda, Parthasarathi Chakraborty, K Das, M Rai, Ojit Singh, P Pradhan, Darshan Singh, Munmun Koley

Indian Journal of Research in Homoeopathy

Context: Clinical verification is an ongoing research program of the Council that verified many rare homoeopathic drugs. Aims: To clinically verify the "symptomatology" of Ocimum canum by ascertaining the prevalence of symptoms. Materials and Methods: The study was a multicenter, open, observational trial. A total of 214 patients were enrolled after matching with the available symptom compendium and eligibility criteria in seven units/institutes of the Council. The medicine was prescribed in 6C, 30C, 200C and 1M potencies as per the need of each patient, following homoeopathic principles and protocol developed by the Council. The collected data were presented in terms …

Ancient Maya Agricultural Resources In The Rio Amarillo Valley Near Copán, Honduras, Bryce Matthew Brown

Theses and Dissertations

The purpose of this study was to use soil physical and chemical analyses to better understand the ancient agricultural landscape around the ancient Maya cities of Rio Amarillo and Piedras Negras, two tributary sites to Copan, Honduras. Our primary objective was to determine whether a mass erosion event around 800 A.D. occurred which could have caused crop failure and famine or if stable soil conditions persisted during the collapse of these city-states. Stable carbon isotope analysis of the humin fraction of the soils showed that much of this valley was used anciently for agriculture, including hillslopes and hilltops; however, there …

Control Of Matrix Metalloproteinases In A Periodontitis Model: Molecules That Trigger Or Inhibit Mmp Production, Catalina Matias Orozco

Theses and Dissertations

In periodontitis, there is a disruption in the homeostasis of the oral microbiome by peridontopathogenic bacteria. However, while bacteria is essential for periodontitis to occur, the severity, pattern and progression of the disease is not solely determined by the microbial burden, and in fact has a lot to do with the overwhelming host inflammatory response. The response can vary even in two individuals with similar periodontopathogenic profiles. The host response leads to extracellular matrix (ECM) destruction, loss of attachment, alveolar bone resorption and eventually, edentulism. The host's reaction is orchestrated by proinflammatory cytokines and chemokines and matrix metalloproteinases (MMPs). MMPs …

An Investigation Of Ssglux, A Glucosidase Co-Expressed With Cslf6 In Oat (Avena Sativa) And Barley (Hordeum Vulgare), Michael Christopher Gines

Theses and Dissertations

Mixed Linkage Glucan (MLG, or (1,3;1,4)-ß-D glucan) is a component of cell walls for major cereal crops and is significant to food and beverage industries. To better understand genetic factors affecting MLG content in oats, this study investigates the presence of glucosidases likely to participate in MLG production. A glucosidase showing co-expression with CslF6—the primary gene responsible for MLG synthesis—could indicate a hand in MLG production by association. Reference genes for expression analysis as well as glucosidase candidates were first selected using in silico methods. In both cases, barley was used as model species because it has abundant public bioinformatic …

Genetically Engineered Crops: How The Courts Dismantled The Doctrine Of Substantial Equivalence, Trevor Findley

Duke Environmental Law & Policy Forum

No abstract provided.

The Trans-Pacific Partnership And The Construction Of A Syncretic Animal Welfare Norm, Andrew Jensen Kerr

Duke Environmental Law & Policy Forum

No abstract provided.

Transgender Bathroom Rights, Catherine Jean Archibald

Duke Journal of Gender Law & Policy

After winning the right to same-sex marriage in all 50 states in June, 2015, the LGBT community is once again battling in court for its rights, this time for the right of transgender people to use bathrooms and locker rooms that match their gender identity. In its “Dear Colleague Letter on Transgender Students,” the Federal Government has recently interpreted federal law as requiring that transgender students be permitted to use bathroom and locker rooms that correspond with their gender identity in schools receiving federal funding. In two separate lawsuits, 20 states have challenged the legitimacy of this interpretation.

This Article …

The Right To Privacy And The Right To Use The Bathroom Consistent With One’S Gender Identity, Vincent J. Samar

Duke Journal of Gender Law & Policy

No abstract provided.

Obergefell’S Legacy, Mark P. Strasser

Duke Journal of Gender Law & Policy

No abstract provided.

The Parched Earth Of Cooperation: How To Solve The Tragedy Of The Commons In International Environmental Governance, Bryan H. Druzin

Duke Journal of Comparative & International Law

This article proposes a way to strengthen international environmental agreements, such as the Paris Agreement and the Kyoto Protocol. Multilateral environmental agreements such as these are extremely fragile. At the heart of the problem is what is known as the tragedy of the commons—a unique dynamic that viciously sabotages cooperation. The cause of this tragedy is that no one can trust that other actors will conserve the common resource, which triggers a race to the bottom—a race to deplete. Global warming and our inability to halt it is perhaps the ultimate example of a tragedy of the commons on a …

Accommodating Students Different Learning Styles With The Use Of Technology, Jaime Prieto

Capstone Projects and Master's Theses

The understanding of different learning styles is crucial for student academic success. The area of concentration pertaining to this topic includes the cognitive development during the adolescent age group selected. To create a good academic foundation, the teacher must exhibit different forms of learning styles to the students to create awareness and a good academic foundation. With the mass inclusion of technology in our society and education system, this research will attempt to understand the positive and negative effects of technology on effecting the students’ ability to use their effective learning style. Through the use of literature reviews and interviews …

A Cad System For Early Diagnosis Of Autism Using Different Imaging Modalities., Marwa Maher Tawfik Ismail

Electronic Theses and Dissertations

The term “autism spectrum disorder” (ASD) refers to a collection of neuro-developmental disorders that affect linguistic, behavioral, and social skills. Autism has many symptoms, most prominently, social impairment and repetitive behaviors. It is crucial to diagnose autism at an early stage for better assessment and investigation of this complex syndrome. There have been a lot of efforts to diagnose ASD using different techniques, such as imaging modalities, genetic techniques, and behavior reports. Imaging modalities have been extensively exploited for ASD diagnosis, and one of the most successful ones is Magnetic resonance imaging(MRI),where it has shown promise for the early diagnosis …

"The Quality Of Women's Intelligence" : Female Humanists In Renaissance Italy., Julie Myers-Mushkin

Electronic Theses and Dissertations

This thesis examines how the advent of humanism in Renaissance Italy impacted women, namely those who were raised within intellectual families and granted educational opportunities not before afforded to members of their sex. In quattrocento Italy, learned women began to circulate their writings and participate in the humanist milieu, and the intellectual lives and published works of these female humanists all in some manner contested Renaissance patriarchy and gender perceptions. As such, this thesis challenges the conception that the Renaissance further disenfranchised women and offers a framework for analyzing and appreciating the ways in which women participated in the academic …

Understanding Adolescents' Unique Experience Of Happiness Within The Family: Bridging Multiple Perspectives Of Adolescents, Parents, And Siblings, Marsha Cohen

Dissertations

The purpose of this phenomenological study was to explore the essence of middle adolescents'; unique experiences of happiness within the family system from the multiple perspectives of adolescents, their parents, and their siblings. Another goal was to make thematic comparisons between and within families in order to better understand the complexity and development of the phenomenon for adolescents. Seven families participated in this study. Each family consisted of a middle adolescent, a parent, and a sibling, yielding a total of 21 participants. A semistructured interview was conducted with each participant. Data were analyzed using Moustakas's (1994) modification of the Stevick-Colaizzi-Keen …

The Bayesian Method Of Estimation For The Number Of Latent Classes In Growth Mixture Models, Chittanun Sitthisan

Dissertations

It is widely accepted that blindly specifying an incorrect number of latent classes may result in misidentifying the class membership of observations and in inconsistently estimated parameters. The current dissertation examined the Bayesian method to estimate the number of latent classes in growth mixture models. The procedure for estimating the number of latent classes was developed via Markov chain Monte Carlo using the Metropolis-Hastings algorithm. The key idea was to construct the likelihood function and then specify the prior information toward the number of latent classes (K), and then calculate the posterior distribution for K. Simulated observations were generated by …

Examining Teachers' And College Students' Perspectives Toward E-Textbooks As An Educational Tool, Nariman Ali Alawami

Dissertations

The purpose of this research was to understand the perspectives of teachers and students regarding their use of specific e-textbooks in a higher education learning environment. The e-textbooks used by the teachers and students were examined in order to determine functions and features to focus on during the inquiry. This study was particularly interested in the design of e-textbooks and how they are used by both teachers and students in the learning process. The participants in the research were also prompted to suggest improvements to e-textbooks. A case study approach was used as the methodology to examine three teachers represented …

Faculty's Knowledge, Pedagogy, And Integration Levels In The Implementation Of Ipads As An Instructional Tool, Xin Wang

Dissertations

Current literature showed there is a need to help faculty improve their iPad integration practices. Using a sequential mixed-methods design, the researcher explored the relationship among faculty’s iPad integration levels, their teachers’ knowledge (TPACK), and pedagogy among faculty members who had integrated iPads into their teaching for at least two semesters. The data were collected with a cross-section questionnaire, follow-up interviews and artifacts. Responses were collected respectively with the three sections of the questionnaire: iPad Usage (N=160), TPACK (N=151), and demographics (N=147). Eight participants were interviewed after the survey. The results indicated TPACK and learning-centered pedagogy were necessary but insufficient …

Biology Laboratories At A Distance: A Case Study And Experiment Of Ecology And Evolution Labs With Community College Students, Beverly E. Ranney

Dissertations

Community colleges deliver more courses online; laboratory-based courses face challenges in how to do this. This study examined how ecology and evolution laboratories could effectively be delivered in an online biology community college course. Virtual simulations and hands-on, at-home kits were used in two groups. Results showed that students using the virtual simulations had higher learning gains and more positive perceptions towards their laboratory experiences than those students using athome kits. By evaluating learning gains on a pretest/posttest and utilizing interviews and focus groups, this research concluded that virtual simulations offered a superior learning experience for online learners. The results …

Aluminum Is More Tightly Bound In Soil After Wollastonite Treatment To A Forest Watershed, Weiyao Gu

Dissertations - ALL

Aluminum concentrations decreased on soil exchange sites and in soil solutions after a whole-watershed wollastonite (CaSiO3) treatment at the Hubbard Brook Experimental Forest in New Hampshire. This study was conducted to determine whether these decreases could be explained by changes in organically bound Al (Alorg) in soils. The concentrations of Alorg, exchangeable Al (AlKCl) and other chemical properties in organic (Oi + Oe, Oa) and 0-10 cm mineral soil layers were measured using samples collected prior to treatment (1998) and afterwards (2002, 2006, 2010 and 2014). Compared to pre-treatment values, Alorg concentrations in the Oa horizon and the 0-10 cm …

Prevalence Of Triple-Negative Breast Cancer In India: Systematic Review And Meta-Analysis, Gurprataap S. Sandhu, Sebhat Erqou, Heidi Patterson, Aju Mathew

Markey Cancer Center Faculty Publications

Purpose There is considerable variation in prevalence rates of triple-negative breast cancer (TNBC) reported by various studies from India. We performed a systematic review and literature-based meta-analysis of these studies.

Methods We searched databases of Medline, Scopus, EMBASE, and Web of Science for studies that reported on the prevalence of TNBC in India that were published between January 1, 1999, and December 31, 2015. We extracted relevant information from each study by using a standardized form. We pooled study-specific estimates by using random-effects meta-analysis to provide summary estimates. We explored sources of heterogeneity by using subgroup analyses and metaregression.

Results …