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Graduate Theses and Dissertations

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Full-Text Articles in Physical Sciences and Mathematics

Studies Aimed At The Synthesis Of Anti-Infective Agents, Ankush Kanwar Apr 2018

Studies Aimed At The Synthesis Of Anti-Infective Agents, Ankush Kanwar

Graduate Theses and Dissertations

Infectious diseases continue to be a major concern worldwide. They are the second leading cause of death after heart disease. Factors such as an increasing global population, travel, urbanization, global climate change and evolution of pathogens have made infectious diseases more common. Infectious diseases, particularly neglected tropical diseases (NTDs) result in many deaths worldwide. Malaria and leishmaniasis are two common (NTDs) which affect low income countries around the globe. Low cost drugs with novel mechanism of action are required to tackle the growing resistances of parasites against current drugs used in the developing world, where most of the cases occur ...


The Association Of Size Variation In The Dental Arch To Third Molar Agenesis For A Modern Population, Devin N. Williams Apr 2018

The Association Of Size Variation In The Dental Arch To Third Molar Agenesis For A Modern Population, Devin N. Williams

Graduate Theses and Dissertations

The frequency with which individuals do not develop their third molars, or wisdom teeth, is increasing worldwide. This current topic of human evolution is relevant to the research of anthropologists, geneticists, dentists, and other researchers involved in the study of human dentition. Many explanations have been offered to account for the prevalence of molar agenesis including, evolutionary, environmental, and genetic theories. The purpose of this research project is to determine the frequency of third molar agenesis and investigate the relationship between third molar agenesis and maxillomandibular jaw dimensions in a sample of orthodontic patients. This research tests the hypotheses that ...


Evaluation Of Academic And Social Engagement In A Technology-Based Collaborative Approach To Inclusive Geoscience Field Learning, Anita Marie Stone Marshall Apr 2018

Evaluation Of Academic And Social Engagement In A Technology-Based Collaborative Approach To Inclusive Geoscience Field Learning, Anita Marie Stone Marshall

Graduate Theses and Dissertations

Field learning is an important aspect of geoscience education to teach or reinforce concepts and skills, and the highly social experience of field work can improve learning outcomes, create networks to support future academic success, and promote a sense of belonging in the geosciences. However, field learning presents significant barriers to participation for students with physical disabilities. The introduction of digital data collection and communication devices into traditional field work settings has created new opportunities to expand access to field learning experiences such as remote collaboration; a method of undertaking field work through collaborative teamwork and the use of digital ...


Characterization Of Nylon-12 In A Novel Additive Manufacturing Technology, And The Rheological And Spectroscopic Analysis Of Peg-Starch Matrix Interactions, Garrett Michael Craft Apr 2018

Characterization Of Nylon-12 In A Novel Additive Manufacturing Technology, And The Rheological And Spectroscopic Analysis Of Peg-Starch Matrix Interactions, Garrett Michael Craft

Graduate Theses and Dissertations

In this work differential scanning calorimetry, dynamic mechanical analysis, Fourier-Transformed Infrared Spectroscopy [FT-IR] and polarized light microscopy will be employed to characterize polymeric systems. The first chapter broadly covers polymer synthesis and important characterization methods.

In the second chapter, a polyamide (PA12) will be sintered via a novel additive manufacturing (AM) technology developed here at USF termed LAPS (Large Area Projection Sintering). LAPS uses extended sintering timespans to ensure complete melting and densification of the polymer powder over the entire two-dimensional area of the part’s footprint. Further, it allows for the printed layer to crystallize and shrink in its ...


Identification Of Individuals From Ears In Real World Conditions, Earnest Eugene Hansley Apr 2018

Identification Of Individuals From Ears In Real World Conditions, Earnest Eugene Hansley

Graduate Theses and Dissertations

A number of researchers have shown that ear recognition is a viable alternative to more common biometrics such as fingerprint, face and iris because the ear is relatively stable over time, the ear is non-invasive to capture, the ear is expressionless, and both the ear’s geometry and shape have significant variation among individuals. Researchers have used different approaches to enhance ear recognition. Some researchers have improved upon existing algorithms, some have developed algorithms from scratch to assist with recognizing individuals by ears, and some researchers have taken algorithms tried and tested for another purpose, i.e., face recognition, and ...


Coarse-Grained Modeling Studies Of Polymeric And Granular Systems, Hong Trung Nguyen Apr 2018

Coarse-Grained Modeling Studies Of Polymeric And Granular Systems, Hong Trung Nguyen

Graduate Theses and Dissertations

This Dissertation is devoted to computational study of the solidification, dynamics and mechanics of model semiflexible polymers with variable chain flexibility as well as a computational investigation of the clogging phenomena observed in granular materials.

Chain stiffness is an intrinsic factor that governs single-chain flexibility. It plays a critical role in the physics of polymeric materials. In this work, we employ a coarse-grained polymer model in which chain stiffness can be tuned by a single parameter (bending stiffness kb) that yields chain shape ranging from coil-like to rod-like in the flexible and very stiff limit respectively. In chapter 2, we ...


Computational Discovery Of Energetic Polynitrogen Compounds At High Pressure, Brad A. Steele Apr 2018

Computational Discovery Of Energetic Polynitrogen Compounds At High Pressure, Brad A. Steele

Graduate Theses and Dissertations

High-nitrogen-content energetic compounds containing multiple N-N bonds are an attractive alternative towards developing new generation of environmentally friendly, and more powerful energetic materials. High-N content translates into much higher heat of formation resulting in much larger energy output, detonation pressure and velocity upon conversion to large amounts of non-toxic, strongly bonded N2 gas. This thesis describes recent advances in the computational discovery of group-I alkali and hydrogen polynitrogen materials at high pressures using powerful first-principles evolutionary crystal structure prediction methods. This is highlighted by the discovery of a new family of materials that consist of long-sought after all-nitrogen N􀀀 5 ...


Synthesis Of Novel Agents For The Treatment Of Infectious And Neurodegenerative Diseases, Benjamin Joe Eduful Apr 2018

Synthesis Of Novel Agents For The Treatment Of Infectious And Neurodegenerative Diseases, Benjamin Joe Eduful

Graduate Theses and Dissertations

Infectious and neurodegenerative diseases continue to be a major concern worldwide. In spite of the great advances in drug therapy for treating various infectious and neurodegenerative diseases, there is still an urgent need for new and improved drugs due to increasing drug resistance among pathogens, emergence of new pathogens, ease of transmission of infections, ineffective available treatments, toxicity associated with current standard of care, aging populations and the lack of better alternative treatment options.

The first part of this manuscript (chapters 1 - 5) describes the synthesis of novel agents active against Leishmania donovani. According to the World Health Organization (WHO ...


Flow And Transport In Low-Gradient Rivers And Estuaries, Hunter Lee Clasen Apr 2018

Flow And Transport In Low-Gradient Rivers And Estuaries, Hunter Lee Clasen

Graduate Theses and Dissertations

For this dissertation I studied flow and transport in low gradient Florida streams. Chapter 2 is a statewide analysis of long-term variations in stream discharge. The results from Chapter 2 suggest that changes in mean annual stream discharge are controlled by the Atlantic Multi-Decadal Oscillation (AMO). During the warm phase, mean annual discharge decreases in central Florida and increases in north Florida. The opposite is true during the cool phase, with mean annual discharge increasing in central Florida and decreasing in north Florida. This pattern is observed for both components of stream discharge, base flow and runoff.

The following two ...


In Situ Extrinsic Doping Of Cdte Thin Films For Photovoltaic Applications, Imran Suhrid Khan Mar 2018

In Situ Extrinsic Doping Of Cdte Thin Films For Photovoltaic Applications, Imran Suhrid Khan

Graduate Theses and Dissertations

The Cadmium Telluride thin film solar cell is one of the leading photovoltaic technologies. Efficiency improvements in the past decade made it a very attractive and practical source of renewable energy. Considering the theoretical limit, there is still room for improvement, especially the cell’s open circuit voltage (VOC). To improve VOC, the p-type carrier concentration and minority carrier lifetime of the CdTe absorber needs to be improved. Both these parameters are directly related to the point defect distribution of the semiconductor, which is a function of deposition stoichiometry, dopant incorporation and post-deposition treatments.

CdTe films were deposited by the ...


A Fall Prevention System For The Elderly And Visually Impaired, Yueng Santiago De La Hoz Isaza Mar 2018

A Fall Prevention System For The Elderly And Visually Impaired, Yueng Santiago De La Hoz Isaza

Graduate Theses and Dissertations

The World Health Organization claims that there are more than 285 million blind and visually impaired people in the world. In the US, 25 million Americans suffer from total or partial vision loss. As a result of their impairment, they struggle with mobility problems, especially the risk of falling. According to the National Council On Aging, falls are among the primary causes for fatal injury and they are the most common cause of non-fatal trauma-related hospital admissions among older adults. Visibility, an organization that helps visually impaired people, reports that people with visual impairments are twice as likely to fall ...


Dynamic Energy-Aware Database Storage And Operations, Peyman Behzadnia Mar 2018

Dynamic Energy-Aware Database Storage And Operations, Peyman Behzadnia

Graduate Theses and Dissertations

Energy consumption has become a first-class optimization goal in design and implementation of data-intensive computing systems. This is particularly true in the design of database management systems (DBMS), which is one of the most important servers in software stack of modern data centers. Data storage system is one of the essential components of database and has been under many research efforts aiming at reducing its energy consumption. In previous work, dynamic power management (DPM) techniques that make real-time decisions to transition the disks to low-power modes are normally used to save energy in storage systems. In this research, we tackle ...


Signal Detection Of Adverse Drug Reaction Using The Adverse Event Reporting System: Literature Review And Novel Methods, Minh H. Pham Mar 2018

Signal Detection Of Adverse Drug Reaction Using The Adverse Event Reporting System: Literature Review And Novel Methods, Minh H. Pham

Graduate Theses and Dissertations

One of the objectives of the U.S. Food and Drug Administration is to protect the public health through post-marketing drug safety surveillance, also known as Pharmacovigilance. An inexpensive and efficient method to inspect post-marketing drug safety is to use data mining algorithms on electronic health records to discover associations between drugs and adverse events.

The purpose of this study is two-fold. First, we review the methods and algorithms proposed in the literature for identifying association drug interactions to an adverse event and discuss their advantages and drawbacks. Second, we attempt to adapt some novel methods that have been used ...


Remote Sensing And Spatial Metrics For Quantifying Seagrass Landscape Changes: A Study On The 2011 Indian River Lagoon Florida Seagrass Die-Off Event, René Dieter Baumstark Mar 2018

Remote Sensing And Spatial Metrics For Quantifying Seagrass Landscape Changes: A Study On The 2011 Indian River Lagoon Florida Seagrass Die-Off Event, René Dieter Baumstark

Graduate Theses and Dissertations

Florida’s seagrasses are ecologically important marine environments which have suffered major degradation caused by increasing anthropogenic pressures. A 2011 seagrass die-off event caused by an algal bloom in the Florida Indian River Lagoon (IRL) was particularly severe with a majority of seagrass lost in areas such as the Banana River. An understanding of how this coastal marine environment changed is an important step toward better managing resources for conservation. Modern tools and methods provide new opportunities to study these changes at the landscape scale, a scale that informs on the larger more comprehensive state of a system. Classified satellite ...


The Stability Of Sand Waves In A Tidally-Influenced Shipping Channel, Tampa Bay, Florida, John Willis Gray Mar 2018

The Stability Of Sand Waves In A Tidally-Influenced Shipping Channel, Tampa Bay, Florida, John Willis Gray

Graduate Theses and Dissertations

Tidally-influenced sandwaves are common coastal features present in various settings, including shipping channels. The main shipping channel in Tampa Bay under the Bob Graham Sunshine Skyway Bridge (a.k.a. the Skyway Bridge) contains such sandwave bedforms. Between the years 2000 and 2017, these bedforms have been surveyed with multibeam echosounders (MBES) on 21 occasions with ranging coverage and quality of returns. Surveys between 2000 and 2009 used a 300 kHz Kongsberg EM3000; surveys between 2015 and 2017 used a 400 kHz Reson Seabat 7125. For comparable surveys, bathymetry, backscatter, slope, curvature, planform curvature, and profile curvature maps were created ...


Geochemical Modeling Of Primary Morb Magmas: Implications For Parental Melting Regimes In Melt Lenses Along-Axis Of The Hess Deep Rift, Stephanie Michelle Drumm Mar 2018

Geochemical Modeling Of Primary Morb Magmas: Implications For Parental Melting Regimes In Melt Lenses Along-Axis Of The Hess Deep Rift, Stephanie Michelle Drumm

Graduate Theses and Dissertations

The Hess Deep Rift in the East Pacific Rise is a mid-ocean ridge spreading center that produces melts which exhibit geochemical characteristics of evolved MORB. Using basaltic glass samples collected from multiple dive cruises that explored Hess Deep geology, volatile and chemical data were collected at USF using FTIR and EMPA, respectively. In addition, a data suite of samples of glass from Hess Deep were compiled from the EarthChem database. The intention was to use the data suite and models to compare the Hess Deep regime to analog models for mid-ocean ridge crystallization regimes and tectonic structures. The USF and ...


Assessment Of Drinking Water Quality Management And A Treatment Feasibility Study For Brick By Brick Water Storage Tanks In Rakai Uganda, James V. Murduca Mar 2018

Assessment Of Drinking Water Quality Management And A Treatment Feasibility Study For Brick By Brick Water Storage Tanks In Rakai Uganda, James V. Murduca

Graduate Theses and Dissertations

Reliable access to safe drinking water is one necessity for humans to live without concern for major health risks. The overall goal of this research is to improve the public health, through improved drinking water, for communities in the Rakai District in Uganda, directly, and other communities in the world, indirectly, via dissemination of knowledge. This study specifically assessed the knowledge of drinking water quality in regards to public health, their sanitation measures, and water treatment methods for users of Brick by Brick rainwater harvesting tanks in the Rakai District (N = 28) by using a knowledge, attitudes, and practice survey ...


Improving The Security Of Building Automation Systems Through An Sel4-Based Communication Framework, Richard Habeeb Mar 2018

Improving The Security Of Building Automation Systems Through An Sel4-Based Communication Framework, Richard Habeeb

Graduate Theses and Dissertations

Existing Building Automation Systems (BASs) and Building Automation Networks (BANs) have been shown to have serious cybersecurity problems. Due to the safety-critical and interconnected nature of building subsystems, local and network access control needs to be finer grained, taking into consideration the varying criticality of applications running on heterogeneous devices. In this paper, we present a secure communication framework for BASs that 1) enforces rich access control policy for operating system services and objects, leveraging a microkernel-based architecture; 2) supports fine-grained network access control on a per-process basis; 3) unifies the security control of inter-device and intra-device communication using proxy ...


Optimal Latin Hypercube Designs For Computer Experiments Based On Multiple Objectives, Ruizhe Hou Mar 2018

Optimal Latin Hypercube Designs For Computer Experiments Based On Multiple Objectives, Ruizhe Hou

Graduate Theses and Dissertations

Latin hypercube designs (LHDs) have broad applications in constructing computer experiments and sampling for Monte-Carlo integration due to its nice property of having projections evenly distributed on the univariate distribution of each input variable. The LHDs have been combined with some commonly used computer experimental design criteria to achieve enhanced design performance. For example, the Maximin-LHDs were developed to improve its space-filling property in the full dimension of all input variables. The MaxPro-LHDs were proposed in recent years to obtain nicer projections in any subspace of input variables. This thesis integrates both space-filling and projection characteristics for LHDs and develops ...


Reduction In Needlestick Injuries Using A Novel Package Of Interventions, Kamal Thakor Patel Mar 2018

Reduction In Needlestick Injuries Using A Novel Package Of Interventions, Kamal Thakor Patel

Graduate Theses and Dissertations

In 2015 Dr. Pratiksha Vaghela started the “Stop Poking Me” campaign which was aimed at curbing the increase in the number of needlesticks at the James A. Haley Veteran Affairs Hospital (JAHVA). The data for needlesticks was collected by the Occupational Medicine Clinic (OMC) between Oct 2013 and Oct 2016. We then obtained the original data from Dr. Vaghela’s project and compared the data to assess whether the new implementations have truly decreased the number of needlesticks. There was a 23.6% reduction in the number of needlesticks between 2013 and 2016 and even more importantly a 60.1 ...


Quantifying The Effect Of Topographic Slope On Lava Flow Thickness: A First Step To Improve Lava Flow Volume Estimation Methods, Steven R. Rizo Mar 2018

Quantifying The Effect Of Topographic Slope On Lava Flow Thickness: A First Step To Improve Lava Flow Volume Estimation Methods, Steven R. Rizo

Graduate Theses and Dissertations

The volume of lava flows provide important information on the magnitude of volcanic eruptions, and accurate volumes are necessary to produce reliable models of lava flow emplacement or constrain the internal structure of volcanoes. The most accurate lava flow volumes are obtainable when the topography before and after an eruption are both known, but information for the topography before lava flow emplacement is absent in non-historic lava flows. To calculate the volume of non-historic lava flows, this pre-emplacement topography needs to be reconstructed. Common methods for this include using inverse distance-weighted averages or global polynomial interpolation methods, but these can ...


A Point Cloud Approach To Object Slicing For 3d Printing, William Edward Oropallo Jr. Mar 2018

A Point Cloud Approach To Object Slicing For 3d Printing, William Edward Oropallo Jr.

Graduate Theses and Dissertations

Various industries have embraced 3D printing for manufacturing on-demand, custom printed parts. However, 3D printing requires intelligent data processing and algorithms to go from CAD model to machine instructions. One of the most crucial steps in the process is the slicing of the object. Most 3D printers build parts by accumulating material layers by layer. 3D printing software needs to calculate these layers for manufacturing by slicing a model and calculating the intersections. Finding exact solutions of intersections on the original model is mathematically complicated and computationally demanding. A preprocessing stage of tessellation has become the standard practice for slicing ...


Design And Implementation Of A Ferrocement Improved Cookstove In Rural Panama, Josh Donegan Mar 2018

Design And Implementation Of A Ferrocement Improved Cookstove In Rural Panama, Josh Donegan

Graduate Theses and Dissertations

Household air pollution contributes to the premature death of more than 4 million people annually. Improved cookstoves are one technological intervention that can potentially reduce exposure to household air pollution. However, improved cookstove implementation programs need to consider measures to increase sustainability and promote long-term adoption. The objectives of this research were 1) to develop and implement a new ferrocement cookstove for Peña Blanca, a rural indigenous community in the Ngäbe-Bugle region of Panama, 2) to evaluate its potential sustainability in comparison to the most common cooking technologies observed in the community, 3) to prepare a construction manual for the ...


Effectiveness Of Biocide Substitution And Management Plan Implementation For The Control Of, Adelmarie Bones Mar 2018

Effectiveness Of Biocide Substitution And Management Plan Implementation For The Control Of, Adelmarie Bones

Graduate Theses and Dissertations

After the notorious outbreak and discovery of Legionella bacteria in 1976, the waterborne pathogen was added to the list of disease-causing agents associated with the built environment. Legionella pneumophila was discovered when it was identified as the agent that caused 34 deaths and an outbreak of pneumonia-like symptoms in several attendees of the 1976 American Legion Convention held in Philadelphia (OSHA, 2017).

Recently published data from the year 2015 reported more than 6,000 Legionnaires’ cases identified in the United States (CDC, 2016). This is a concerning number given that one in every ten infected persons will die of the ...


Angiostrongylus Cantonensis: Epidemiologic Review, Location-Specific Habitat Modelling, And Surveillance In Hillsborough County, Florida, U.S.A., Brad Christian Perich Mar 2018

Angiostrongylus Cantonensis: Epidemiologic Review, Location-Specific Habitat Modelling, And Surveillance In Hillsborough County, Florida, U.S.A., Brad Christian Perich

Graduate Theses and Dissertations

Angiostrongylus cantonensis is a parasitic nematode endemic to tropical and subtropical regions and is the leading cause of human eosinophilic meningitis. The parasite is commonly known as rat lungworm because the primary host in its lifecycle is the rat. A clinical overview of rat lungworm infection is presented, followed by a literature review of rat lungworm epidemiology, risk factors, and surveillance projects. Data collected from previous snail surveys in Florida was considered alongside elevation, population per square kilometer, median household income by zip code territory, and normalized difference vegetation index specific to the geographic coordinates from which the snail samples ...


Assessing The Impacts Of Climate Change On Streamflow And Reservoir Operation In Central Florida, Toni Panaou Jan 2018

Assessing The Impacts Of Climate Change On Streamflow And Reservoir Operation In Central Florida, Toni Panaou

Graduate Theses and Dissertations

Climate change is a global concern as it may affect many aspects of life, including water supply. A tool used to model climate change’s impacts is called a General Circulation Model (GCM). GCMs project future scenarios including temperature and precipitation, but these are designed at a coarse resolution and require downscaling for employment for regional hydrologic modeling. There is a vast amount of research on downscaling and bias-correcting GCMs data, but it is unknown whether these techniques alter precipitation signals embedded in these models or reproduce climate states that are viable for water resource planning and management. Using the ...


The Role Of Biosolids-Derived Dissolved Organic Matter On The Interaction Of Selected Endocrine-Disrupting Chemicals With Two Alluvial Soils, Fritzie Rivas Jan 2018

The Role Of Biosolids-Derived Dissolved Organic Matter On The Interaction Of Selected Endocrine-Disrupting Chemicals With Two Alluvial Soils, Fritzie Rivas

Graduate Theses and Dissertations

Overpopulation is one of the major causes of many environmental problems we experience today. With increasing population, the demand for quality food and clean water is becoming difficult to realize. Although with advancement in technology, we are still able to cope with the demand, but eventually we will exhaust the supply for quality food and clean water as well as the different methods of achieving them.

Quality food and clean water are necessities to live. To help in delivering these needs, federal regulations and policies were developed and implemented to protect the public from environmental contaminants that might be hazardous ...


Structures And Dynamics Investigation Of Phase Selection In Metallic Alloy Systems, Lin Yang Jan 2018

Structures And Dynamics Investigation Of Phase Selection In Metallic Alloy Systems, Lin Yang

Graduate Theses and Dissertations

Different phases of metallic alloys have a wide range of applications. However, the driving mechanisms of the phase selections can be complex. For example, the detailed pathways of the phase transitions in the devitrification process still lack a comprehensive interpretation. So, the understanding of the driving mechanisms of the phase selections is very important.

In this thesis, we focus on the study of the Al-Sm and other related metallic alloy systems by simulation and experiment. A procedure to evaluate the free energy has been developed within the framework of thermodynamic integration, coupled with extensive GPU-accelerated molecular dynamics (MD) simulations; The ...


Evaluation Of Nitrogen And Potassium Interactions In Corn, Jackson Hirniak Jan 2018

Evaluation Of Nitrogen And Potassium Interactions In Corn, Jackson Hirniak

Graduate Theses and Dissertations

Research is needed to further evaluate N by K interactions in crops. The objective of this study was to evaluate potential interactions in corn (Zea mays L.). Two long-term trials with continuous corn were evaluated from 2013 to 2017 in two Iowa soils. Annual treatments were the combinations of five N rates (0-336 kg N ha-1) and four K rates (0-66 kg K ha-1) replicated three times. Grain yield, ear-leaf (R1 stage) and grain (at harvest) N and K concentrations, N and K removed with grain harvest, and post-harvest soil-test K (STK) (15-cm depth) were measured each year. Leaf N ...


The Growing Together Project: Understanding Impacts On Field Day Attendees And Iowa Master Gardeners, Laura Irish Jan 2018

The Growing Together Project: Understanding Impacts On Field Day Attendees And Iowa Master Gardeners, Laura Irish

Graduate Theses and Dissertations

Citizen science has been shown to be an effective tool for increasing data collection, as well as a great benefit to those who participate in the research project. The rising costs and limited funding for conducting large-scale research projects make citizen science projects valuable assets for researchers. Understanding the impact of citizen science projects on the volunteers must be done to better engage with and retain the volunteers. The Growing Together project, a partnership between the ISU Extension and Outreach Master Gardener program and the Human Sciences Extension, was created to increase food security in Iowa. The two major components ...