Medicine and Health Sciences Commons^™

Grid-Based Fourier Transform Phase Contrast Imaging, Sajjad Tahir

Legacy Theses & Dissertations (2009 - 2024)

Low contrast in x-ray attenuation imaging between different materials of low electron density is a limitation of traditional x-ray radiography. Phase contrast imaging offers the potential to improve the contrast between such materials, but due to the requirements on the spatial coherence of the x-ray beam, practical implementation of such systems with tabletop (i.e. non-synchrotron) sources has been limited. One recently developed phase imaging technique employs multiple fine-pitched gratings. However, the strict manufacturing tolerances and precise alignment requirements have limited the widespread adoption of grating-based techniques. In this work, we have investigated a technique recently demonstrated by Bennett et al.1 …

An Investigation Of Alkaline Earth And Rare Earth Elements In Human Bone Following Long-Term Parenteral Nutrition, Aubrey L. Galusha

Legacy Theses & Dissertations (2009 - 2024)

This investigation focused on a unique collection of archived human bones obtained post-mortem from 7 patients, who had received long-term parenteral nutrition (PN) for up to 21 years. Parenterals are administered intravenously as a nutritional supplement, and may be contaminated with metals, which are completely absorbed into the blood compartment. Some metal contaminants may be deposited in the body’s reservoir for inorganic elements – bone.

Phase Imaging Using Focusing Polycapillary Optics, Sajid Bashir

Legacy Theses & Dissertations (2009 - 2024)

The interaction of X rays in diagnostic energy range with soft tissues can be described by Compton scattering and by the complex refractive index, which together characterize the attenuation properties of the tissue and the phase imparted to X rays passing through it. Many soft tissues exhibit extremely similar attenuation, so that their discrimination using conventional radiography, which generates contrast in an image through differential attenuation, is challenging. However, these tissues will impart phase differences significantly greater than attenuation differences to the X rays passing through them, so that phase-contrast imaging techniques can enable their discrimination.

The Genesis And Emergence Of Community-Associated Methicillin-Resistant Staphylococcus Aureus (Ca-Mrsa): An Example Of Evolution In Action?, Alan L. Gillen, Jason Conrad, Michael Cargill

Faculty Publications and Presentations

Staphylococcus aureus infections are a common cause of disease, particularly in colonized persons. Recently, a series of published articles have reported that community-acquired methicillin-resistant S. aureus (CA-MRSA) strains are evolving and increasingly becoming prevalent in households while health care acquired MRSA (HA-MRSA) is declining in the USA. The changing superbugs have often been used as an example of evolution in action. Although MRSA infections have become increasingly reported in the community, population-based studies of students preparing for the health professions having S. aureus and MRSA colonization are lacking. During the 2014–2015 school year 544 students were tested for MRSA carriage …

Saccharomyces Boulardii And Bismuth Subsalicylate As Low-Cost Interventions To Reduce The Duration And Severity Of Cholera, Johnathan Sheele, Jessica Cartowski, Angela Dart, Arjun Poddar, Shikha Gupta, Ajay Gupta

Computer Science Faculty Publications

We conducted a randomised single-blinded clinical trial of 100 cholera patients in Port-au-Prince, Haiti to determine if the probiotic Saccharomyces cerevisiae var. boulardii and the anti-diarrhoeal drug bismuth subsalicylate (BS) were able to reduce the duration and severity of cholera. Subjects received either: S. boulardii 250 mg, S. boulardii 250 mg capsule plus BS 524 mg tablet, BS 524 mg, or two placebo capsules every 6 hours alongside standard treatment for cholera. The length of hospitalisation plus the number and volume of emesis, stool and urine were recorded every 6 hours until the study subject was discharged (n=83), left against …

A Dynamic Programming Algorithm For Finding The Optimal Placement Of A Secondary Structure Topology In Cryo-Em Data, Abhishek Biswas, Desh Ranjan, Mohammad Zubair, Jing He

Computer Science Faculty Publications

The determination of secondary structure topology is a critical step in deriving the atomic structures from the protein density maps obtained from electron cryomicroscopy technique. This step often relies on matching the secondary structure traces detected from the protein density map to the secondary structure sequence segments predicted from the amino acid sequence. Due to inaccuracies in both sources of information, a pool of possible secondary structure positions needs to be sampled. One way to approach the problem is to first derive a small number of possible topologies using existing matching algorithms, and then find the optimal placement for each …

Risk Based Optimization For Improving Emergency Medical Systems, Sandhya Saisubramanian, Pradeep Varakantham, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

In emergency medical systems, arriving at the incident location a few seconds early can save a human life. Thus, this paper is motivated by the need to reduce the response time – time taken to arrive at the incident location after receiving the emergency call – of Emergency Response Vehicles, ERVs (ex: ambulances, fire rescue vehicles) for as many requests as possible. We expect to achieve this primarily by positioning the "right" number of ERVs at the "right" places and at the "right" times. Given the exponentially large action space (with respect to number of ERVs and their placement) and …

Characterization Of Calbindin Positive Interneurons Within The Ventral Horn Of The Mouse Spinal Cord, Taylor L. Floyd, David R. Ladle

Celebration of Undergraduate & Graduate Research, Scholarship, and Creative Activities Materials

Sensory-motor circuits in the spinal cord integrate sensory feedback from muscles and modulate locomotor behavior. Although we know how the sensory-motor system generally works, the main issue lies in identifying all neurons involved and understanding their interrelationships. Many interneurons contribute to sensory-motor circuits and have been well studied. For example, Renshaw cells (RC) are inhibitory interneurons that prevent motor neurons from over-activity. A distinguishing feature of RCs is that they are the only interneurons within the ventral-most region of the spinal cord expressing the calcium binding protein calbindin (CB). Recent studies have found other subpopulations of ventral horn interneurons outside …

Comparison Of Blood Lead Levels Between Children In An Urban Setting And Children In A Rural Setting, Juan Manuel Alvarez

Open Access Theses & Dissertations

Environmental heavy metal exposure is a public health problem that is of great concern because it is highly toxic for children. The urban setting in downtown El Paso is historically known to be contaminated through various sources of contamination of heavy metals. The goal of this study was to compare whether children in a historically contaminated urban downtown area had significantly increased levels of lead exposure as compared to children in a demographically similar rural area approximately 20 miles north of the urban center, while controlling for gender and age. Cadmium and mercury were also measured for comparison purposes. It …

A Pilot Study Of Arsenic In Young Children From Two Rural West Texas Communities: Blood Levels, Household Water Levels, And Behavioral Outcomes, Michelle Del Rio

Open Access Theses & Dissertations

Background & Significance: Heavy metals have been identified as a child health hazard because children are highly vulnerable to the effects of exposure, which can be physical, cognitive, and behavioral. Levels of arsenic (As) greater than the EPA Maximum Contaminant Level (10μg/L) were identified in some household water samples in two rural west Texas communities located within 20 miles of the U.S.-Mexico border by a Health Impact Assessment conducted in 2013 (Hargrove, Juarez-Carillo, & Korc 2015). Whether home water samples predicted child blood As levels needed to be examined. Since lead (Pb) is another common heavy metal contaminant in the …

Advances And Applications Of Dezert-Smarandache Theory (Dsmt) For Information Fusion (Collected Works), Vol. 4, Florentin Smarandache, Jean Dezert

Branch Mathematics and Statistics Faculty and Staff Publications

The fourth volume on Advances and Applications of Dezert-Smarandache Theory (DSmT) for information fusion collects theoretical and applied contributions of researchers working in different fields of applications and in mathematics. The contributions (see List of Articles published in this book, at the end of the volume) have been published or presented after disseminating the third volume (2009, http://fs.unm.edu/DSmT-book3.pdf) in international conferences, seminars, workshops and journals.

First Part of this book presents the theoretical advancement of DSmT, dealing with Belief functions, conditioning and deconditioning, Analytic Hierarchy Process, Decision Making, Multi-Criteria, evidence theory, combination rule, evidence distance, conflicting belief, sources of evidences …

Diffuse Optical Measurements Of Head And Neck Tumor Hemodynamics For Early Prediction Of Chemo-Radiation Therapy Outcomes, Lixin Dong

Theses and Dissertations--Biomedical Engineering

Chemo-radiation therapy is a principal modality for the treatment of head and neck cancers, and its efficacy depends on the interaction of tumor oxygen with free radicals. In this study, we adopted a novel hybrid diffuse optical instrument combining a commercial frequency-domain tissue oximeter (Imagent) and a custom-made diffuse correlation spectroscopy (DCS) flowmeter, which allowed for simultaneous measurements of tumor blood flow and blood oxygenation. Using this hybrid instrument we continually measured tumor hemodynamic responses to chemo-radiation therapy over the treatment period of 7 weeks. We also explored monitoring dynamic tumor hemodynamic changes during radiation delivery. Blood flow data analysis …

Design, Synthesis, And Pharmacological Evaluation Of Three Series Of Lobelane Analogs As Inhibitors Of The Vesicular Monoamine Transporter (Vmat2), John P. Culver

Theses and Dissertations--Pharmacy

Methamphetamine (METH) abuse is a serious problem in the United States and worldwide. The reward experienced by METH users is due to the increase in extracellular dopamine (DA) concentrations caused by an interaction between METH and the DA transporter (DAT) as well as the Vesicular Monoamine Transporter-2 (VMAT2). The reward felt by users of METH leads to further use of the drug and subsequent abuse. The current project examined the ability of three novel series of lobelane analogs to interact with a binding site on the Vesicular Monoamine Transporter-2 (VMAT2) in an attempt to inhibit the effects of METH. Lobelane …

Chemoenzymatic Studies To Enhance The Chemical Space Of Natural Products, Jhong-Min Chen

Theses and Dissertations--Pharmacy

Natural products provide some of the most potent anticancer agents and offer a template for new drug design or improvement with the advantage of an enormous chemical space. The overall goal of this thesis research is to enhance the chemical space of two natural products in order to generate novel drugs with better in vivo bioactivities than the original natural products.

Polycarcin V (PV) is a gilvocarcin-type antitumor agent with similar structure and comparable bioactivity with the principle compound of this group, gilvocarcin V (GV). Modest modifications of the polyketide-derived tetracyclic core of GV had been accomplished, but the most …

A Molecular-Level View Of The Physical Stability Of Amorphous Solid Dispersions, Xiaoda Yuan

Theses and Dissertations--Pharmacy

Many pharmaceutical compounds being developed in recent years are poorly soluble in water. This has led to insufficient oral bioavailability of many compounds in vitro. The amorphous formulation is one of the promising techniques to increase the oral bioavailability of these poorly water-soluble compounds. However, an amorphous drug substance is inherently unstable because it is a high energy form. In order to increase the physical stability, the amorphous drug is often formulated with a suitable polymer to form an amorphous solid dispersion. Previous research has suggested that the formation of an intimately mixed drug-polymer mixture contributes to the stabilization …

Developments In Nonparametric Regression Methods With Application To Raman Spectroscopy Analysis, Jing Guo

Theses and Dissertations--Epidemiology and Biostatistics

Raman spectroscopy has been successfully employed in the classification of breast pathologies involving basis spectra for chemical constituents of breast tissue and resulted in high sensitivity (94%) and specificity (96%) (Haka et al, 2005). Motivated by recent developments in nonparametric regression, in this work, we adapt stacking, boosting, and dynamic ensemble learning into a nonparametric regression framework with application to Raman spectroscopy analysis for breast cancer diagnosis. In Chapter 2, we apply compound estimation (Charnigo and Srinivasan, 2011) in Raman spectra analysis to classify normal, benign, and malignant breast tissue. We explore both the spectra profiles and their derivatives to …

Nonlinear Hierarchical Models For Longitudinal Experimental Infection Studies, Michael David Singleton

Theses and Dissertations--Epidemiology and Biostatistics

Experimental infection (EI) studies, involving the intentional inoculation of animal or human subjects with an infectious agent under controlled conditions, have a long history in infectious disease research. Longitudinal infection response data often arise in EI studies designed to demonstrate vaccine efficacy, explore disease etiology, pathogenesis and transmission, or understand the host immune response to infection. Viral loads, antibody titers, symptom scores and body temperature are a few of the outcome variables commonly studied. Longitudinal EI data are inherently nonlinear, often with single-peaked response trajectories with a common pre- and post-infection baseline. Such data are frequently analyzed with statistical methods …

The Relationship Between Information Technology And Organizational Effectiveness As Perceived By Health Care Providers, Christian Chikwem Ukaga

Walden Dissertations and Doctoral Studies

The U.S. Congress has made health information technology a central component of the national quest to improve health care delivery. The problem addressed in this study was the uncertainty among healthcare providers regarding the benefits of health care information technology adoption relative to healthcare delivery processes and outcomes. The purpose of the study was to understand the effectiveness of information technology as perceived by healthcare providers. The research questions were designed to investigate the relationship between health information technology and organizational effectiveness, exchange of information, organizational process, organizational productivity, and direct personal care. Sociotechnical systems theory and Donabedian's framework for …

Cybersecurity Vulnerabilities In Medical Devices: A Complex Environment And Multifaceted Problem, Patricia A.H. Williams, Andrew J. Woodward

Research outputs 2014 to 2021

The increased connectivity to existing computer networks has exposed medical devices to cybersecurity vulnerabilities from which they were previously shielded. For the prevention of cybersecurity incidents, it is important to recognize the complexity of the operational environment as well as to catalog the technical vulnerabilities. Cybersecurity protection is not just a technical issue; it is a richer and more intricate problem to solve. A review of the factors that contribute to such a potentially insecure environment, together with the identification of the vulnerabilities, is important for understanding why these vulnerabilities persist and what the solution space should look like. This …

Exploration Of Materials Used In 3-Dimensional Printing For The Dental Industry, Holly Chang Hayden

Scripps Senior Theses

A limiting factor in the digitization of dental devices is the availability of materials suitable for use in both dentistry and the new digital technologies. As a rapidly growing industry, three-dimensional printing (3DP) has the potential to disrupt traditional manufacturing and prototyping methods. A review of both restorative materials and the current 3DP materials has lead to a focus on fiber- reinforced composites in the exploration for a new 3DP material. In addition, another area worth exploring and investing in would be 3D bioprinting as it opens up the possibility of regenerative dentistry.

Outcomes Of Asymmetric Selection Pressure And Larval Dispersal On Evolution Of Disease Resistance: A Metapopulation Modeling Study With Oysters, Daphne M. Munroe, Eric N. Powell, Susan E. Ford, Eileen E. Hofmann, John M. Klinck

CCPO Publications

Marine diseases are a strong selective force that can have important economic and ecological consequences. Larval dispersal patterns, selective mortality and individual growth rates can modulate metapopulation responses to disease pressure. Here, we use a modeling framework that includes distinct populations, connected via larval transport, with varying disease selection pressure and connectivity to examine how these dynamics enhance or inhibit the evolution of disease resistance in metapopulations. Our system, oysters and MSX disease, is one in which disease resistance is highly and demonstrably heritable. Simulations show that under conditions of population isolation (i.e. local retention of larvae) and strong disease …

Sharp Rna Recognition Motif Optimizations, Extensions, And Mutations For Use In 2d And 3d Nmr Experiments, Shaun M. Christie

Williams Honors College, Honors Research Projects

SMRT/HDAC Associated Repressor Protein interacts with the long noncoding RNA, produced by SRA, by binding at the RRMs. Three projects were done to prepare the truncated proteins for use in 2D and 3D NMR experiments. The first focuses on RRM 3 and its optimization during the purification process. The second focuses on RRM 2-4, which was found to be missing two alpha helices that may be important for protein stability. These helices can also interact with RRM 3 as well due to the tight association of RRMs 3 and 4. The two step PCR extension of RRM 2-4 was assumed …

Security Of Eprescription: Security Of Data At Rest In Prescription Exchange Services Vs On Mobile Devices, Kyaw Kyaw Htat, Patricia A. H. Williams, Vincent Mccauley

Australian eHealth Informatics and Security Conference

One area of healthcare that has moved more quickly than others in adopting electronic transfer of information is prescribing in the primary care environment. Several Acts and Regulations have been repealed and amended at Commonwealth and State levels to enable this progress over the past decade, as medication provision is a strictly controlled area of healthcare. Further, numerous standards and specifications have been developed and adopted to support and safeguard the regulatory changes and facilitate the electronic transfer of prescriptions. However, the current model of electronic prescription transfer comes with a substantial price tag for ongoing use. With the Nation’s …

Climate, Environmental And Socio-Economic Change: Weighing Up The Balance In Vector-Borne Disease Transmission, Paul E. Parham, Joanna Waldock, George K. Christophides, Deborah Hemming, Folashade Agusto, Katherine J. Evans, Nina Fefferman, Holly Gaff, Abba Gumel, Shannon Ladeau

Biological Sciences Faculty Publications

Arguably one of the most important effects of climate change is the potential impact on human health. While this is likely to take many forms, the implications for future transmission of vector-borne diseases (VBDs), given their ongoing contribution to global disease burden, are both extremely important and highly uncertain. In part, this is owing not only to data limitations and methodological challenges when integrating climate-driven VBD models and climate change projections, but also, perhaps most crucially, to the multitude of epidemiological, ecological and socio-economic factors that drive VBD transmission, and this complexity has generated considerable debate over the past 10-15 …

The Hare And The Hortoise [Sic]: The Potential Versus The Reality Of Etp Implementation, Kyaw Kyaw Htat, Patricia A. H Williams, Vincent Mccauley

Research outputs 2014 to 2021

In a health system increasingly driven by cost constraints, there is a focus on improved electronic transfer of information to support healthcare delivery. One area of healthcare that has moved more quickly than others to achieve this is prescribing in the primary care environment. Whilst the move to electronic transfer of prescriptions has reduced transcription errors, the regulatory environment persists with handwritten signatures. This constraint, whilst addressed slowly with technology solutions, needs support from legislative change. The ultimate step is to have a secure mobile model, which would support the move to a fully-electronic, paperless transaction model.

Killing Adherent And Nonadherent Cancer Cells With The Plasma Pencil, Mounir Laroussi, Soheila Mohades, Nazir Barekzi

Electrical & Computer Engineering Faculty Publications

The application of low temperature plasmas in biology and medicine may lead to a paradigm shift in the way various diseases can be treated without serious side effects. Low temperature plasmas generated in gas mixtures that contain oxygen or air produce several chemically reactive species that have important biological implications when they interact with eukaryotic or prokaryotic cells. Here, a review of the effects of low temperature plasma generated by the plasma pencil on different cancerous cells is presented. Results indicate that plasma consistently shows a delayed killing effect that is dose dependent. In addition, there is some evidence that …

The Multimodal Brain Tumor Image Segmentation Benchmark (Brats), Bjoern H. Menze, Andras Jakab, Stefan Bauer, Jayashree Kalpathy-Cramer, Khan M. Iftekharuddin, Syed M.S. Reza

Electrical & Computer Engineering Faculty Publications

In this paper we report the set-up and results of the Multimodal Brain Tumor Image Segmentation Benchmark (BRATS) organized in conjunction with the MICCAI 2012 and 2013 conferences. Twenty state-of-the-art tumor segmentation algorithms were applied to a set of 65 multi-contrast MR scans of low-and high-grade glioma patients-manually annotated by up to four raters-and to 65 comparable scans generated using tumor image simulation software. Quantitative evaluations revealed considerable disagreement between the human raters in segmenting various tumor sub-regions (Dice scores in the range 74%-85%), illustrating the difficulty of this task. We found that different algorithms worked best for different sub-regions …

Total Synthesis Of Clavatadine A Analogs To Produce A Viable Reversible Inhibitor For Factor Xia, Christopher E. Malmberg

All Master's Theses

Cardiovascular disease has quickly become a major health concern in the United States, with numerous citizens dying from cardiovascular disease each year. Older medications, while effective against cardiovascular disease, are problematic to prescribe. A recently isolated natural product, clavatadine A, selectively inhibits human blood coagulation factor XIa. As a result, the synthesis and biological testing of clavatadine A and synthetic clavatadine A analogues that selectively inhibit factor XIa would represent a new direction in cardiovascular disease research. A potent and selective factor XIa inhibitor has the potential to be a safer replacement for current anticoagulants, such as Warfarin, Pradaxa^{® …}

An Appraisal Of Experiences Of Climate Change And Adaptive Response To Heat Stress By Farmers In Rural Ghana, Kwasi Frimpong

Theses: Doctorates and Masters

With the increase in average global temperatures, heat-related illnesses and deaths have unfolded as occupational and health issues. Periods of high to extreme temperatures are becoming more common and are a leading cause of weather-related deaths in many countries. In agricultural settings of African countries, heat stress is a major concern as many smallholder farmers work outdoors with limited access to cooling systems even in their resting and living environments. This study, conducted in the Bawku East part of Northern-East Ghana in 2013, examines, in the context of climate change, the trends and impacts of heat stress on smallholder farmers, …

Effects Of Ambient Coarse, Fine, And Ultrafine Particles And Their Biological Constituents On Systemic Biomarkers: A Controlled Human Exposure Study, Ling Liu, Bruce Urch, Raymond Poon, Mieczyslaw Szyszkowicz, Mary Speck, Diane R. Gold, Amanda J. Wheeler, James A. Scott, Jeffrey R. Brook, Peter S. Thorne, Frances S. Silverman

Research outputs 2014 to 2021

Background: Ambient coarse, fine, and ultrafine particles have been associated with mortality and morbidity. Few studies have compared how various particle size fractions affect systemic biomarkers. Objectives: We examined changes of blood and urinary biomarkers following exposures to three particle sizes. Methods: Fifty healthy nonsmoking volunteers, mean age of 28 years, were exposed to coarse (2.5–10 μm; mean, 213 μg/m3) and fine (0.15–2.5 μm; mean, 238 μg/m3) concentrated ambient particles (CAPs), and filtered ambient and/or medical air. Twenty-five participants were exposed to ultrafine CAP (< 0.3 μm; mean, 136 μg/m3) and filtered medical air. Exposures lasted 130 min, separated by ≥ 2 weeks. Blood/urine samples were collected preexposure and 1 hr and 21 hr postexposure to determine blood interleukin-6 and C-reactive protein (inflammation), endothelin-1 and vascular endothelial growth factor (VEGF; vascular mediators), and malondialdehyde (lipid peroxidation); as well as urinary VEGF, 8-hydroxy-deoxy-guanosine (DNA oxidation), and malondialdehyde. Mixed-model regressions assessed pre- and postexposure differences. results: One hour postexposure, for every 100-μg/m3 increase, coarse CAP was associated with increased blood VEGF (2.41 pg/mL; 95% CI: 0.41, 4.40) in models adjusted for O3, fine CAP with increased urinary malondialdehyde in single- (0.31 nmol/mg creatinine; 95% CI: 0.02, 0.60) and two-pollutant models, and ultrafine CAP with increased urinary 8-hydroxydeoxyguanosine in single- (0.69 ng/mg creatinine; 95% CI: 0.09, 1.29) and two-pollutant models, lasting < 21 hr. Endotoxin was significantly associated with biomarker changes similar to those found with CAPs. conclusions: Ambient particles with various sizes/constituents may influence systemic biomarkers differently. Endotoxin in ambient particles may contribute to vascular mediator changes and oxidative stress.