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Can Including Time Delay In Epidemic Models Significantly Improve Predictions Concerning Intervention Strategies?, Adrienna N. Bingham, Leah Shaw

Biology and Medicine Through Mathematics Conference

No abstract provided.

General Models For Ecological Drivers Of Poverty, Calistus Ngeh Ngonghala

Biology and Medicine Through Mathematics Conference

No abstract provided.

Genetic Engineering And Sustainable Crop Disease Management: Opportunities For Case-By-Case Decision-Making, Paul Vincelli

Plant Pathology Faculty Publications

Genetic engineering (GE) offers an expanding array of strategies for enhancing disease resistance of crop plants in sustainable ways, including the potential for reduced pesticide usage. Certain GE applications involve transgenesis, in some cases creating a metabolic pathway novel to the GE crop. In other cases, only cisgenessis is employed. In yet other cases, engineered genetic changes can be so minimal as to be indistinguishable from natural mutations. Thus, GE crops vary substantially and should be evaluated for risks, benefits, and social considerations on a case-by-case basis. Deployment of GE traits should be with an eye towards long-term sustainability; several …

Evaluating Infection Prevention Strategies In Out-Patient Dialysis Units Using Agent-Based Modeling, Joanna R. Wares, Barry Lawson, Douglas Shemin, Erika D'Agata

Department of Math & Statistics Faculty Publications

Patients receiving chronic hemodialysis (CHD) are among the most vulnerable to infections caused by multidrug-resistant organisms (MDRO), which are associated with high rates of morbidity and mortality. Current guidelines to reduce transmission of MDRO in the out-patient dialysis unit are targeted at patients considered to be high-risk for transmitting these organisms: those with infected skin wounds not contained by a dressing, or those with fecal incontinence or uncontrolled diarrhea. Here, we hypothesize that targeting patients receiving antimicrobial treatment would more effectively reduce transmission and acquisition of MDRO. We also hypothesize that environmental contamination plays a role in the dissemination of …

Inhibitory Effects Of Unique Sulfonamides On Leishmania Tarentolae And Potential Pathway Of Inhibition, Jade M. Katinas

Theses and Dissertations

Leishmaniasis is an endemic disease caused by the protozoan parasite Leishmania. Current treatments for the parasite are limited by cost, availability, and drug resistance as the worldwide occurrence of leishmaniasis continues to be more prevalent. Sulfonamides are a class of compounds with medicinal properties that have been used to treat bacterial and parasitic diseases via various pathways. In this study, newly synthesized, unique structural analogs of sulfonamide compounds were assessed for their impact on Leishmania cell viability and potential pathways for inhibition were evaluated. Leishmania tarentolae (ATCC Strain 30143) axenic promastigote cells were grown in BHI medium and treated with …

Synthesis And Evaluation Of Biological Activity Of A Potential Immunomodulatory Zwitterionic Polysaccharide, Vikram Basava

Seton Hall University Dissertations and Theses (ETDs)

The gram-negative anaerobic bacterium Bacteroides fragilis is an integral component of the normal gastrointestinal flora. The bacterium colonizes the intestinal tract of human beings as it has no reservoir other than mammals. An unprecedented proportion of the genomic DNA of B. fragilus is involved in the production of capsular polysaccharides. These capsular polysaccharides are important virulence factors in most extracellular bacterial pathogens. Eight of these polysaccharides have been identified thus far, out of which two were found to be zwitterionic polymers, PSA1 and PSA2. PSA1 was found to stimulate T-cell lineage of the immune system because of the dual charge …

How Infectious Was #Deflategate?, Megan Eberle, Eric A. Eager, James Peirce

Spora: A Journal of Biomathematics

In mid-January 2015 the National Football League (NFL) started an investigation into whether the New England Patriots deliberately deflated the footballs used during their AFC Championship win. Like an infectious disease, the initial discussion regarding Deflategate grew rapidly on social media sites in the days after the release of the story, only to slowly dissipate as interest in the NFL waned following the completion of its season. We apply a simple epidemic model for the infectiousness of the Deflategate news story. We find that the infectiousness of Deflategate rivals that of many of the infectious diseases that we have seen …

Fluctuating Survival Selection Explains Variation In Avian Group Size, Charles R. Brown, Mary Bomberger Brown, Erin A. Roche, Valerie A. O'Brien, Catherine E. Page

School of Natural Resources: Faculty Publications

Most animal groups vary extensively in size. Because individuals in certain sizes of groups often have higher apparent fitness than those in other groups, why wide group size variation persists in most populations remains unexplained. We used a 30-y mark– recapture study of colonially breeding cliff swallows (Petrochelidon pyrrhonota) to show that the survival advantages of different colony sizes fluctuated among years. Colony size was under both stabilizing and directional selection in different years, and reversals in the sign of directional selection regularly occurred. Directional selection was predicted in part by drought conditions: birds in larger colonies tended …

Progression Magazine, 2016 Spring, Coastal Carolina University

Progression Magazine

Magazine of the College of Science at Coastal Carolina University.

Modeling Consequences Of Reduced Vaccination Levels On The Spread Of Measles, Guillermo Ortiz

Honors Program Theses and Projects

Introduction: In this thesis we propose a mathematical model for the spread of measles in a closed population. In section 1 we offer a motivation for the project, describe the measles virus as well as its history in the U.S., and provide a brief summary of three epidemiological models from the literature. In section 2.1 we introduce some probabilistic tools used in our model. Section 2.2.1 outlines our stochastic model used for the spread of measles in a population, which is refined in section 2.2.2 to include health interventions from the CDC. We conclude the thesis by presenting in section …

Dissemination And Persistence Of Plasmid Located, Integron Associated Antibiotic Resistant Genes In Wastewater Treatment Plant Effluent And Stream Water Bacteria, _ Suhartono

Graduate Theses and Dissertations

Transmissible plasmid-mediated integrons play important role in the persistence and dissemination of antibiotic resistance throughout the environment. Plasmids from 139 multi-antibiotic resistant Escherichia coli recovered from wastewater treatment plant effluent and upstream and downstream receiving stream water in Northwest Arkansas were extracted and profiled. Genes of class 1 and class 2 integrase (intI), mobilization (mob), sulfamethoxazole resistance (sul), and trimethoprim resistance (dfr) were detected using PCR and confirmed through DNA sequencing. Plasmids from almost half of the isolates (47%) were transmissible with mobF12 gene as the most frequently detected mobilization gene. Plasmid-borne class 1 with and without class 2 integrons …

Development Of Arginyl-Trna Synthetase From Pseudomonas Aeruginosa As A Platform To Screen For Inhibitors Of Protein Synthesis, Daniel Cantu

Theses and Dissertations

Pseudomonas aeruginosa is a Gram- negative bacteria that is the leading cause of mortality in immunocompromised patients. Arginyl-tRNA synthetase (ArgRS) is an enzyme that catalyzes the covalent attachment of arginine to the cognate tRNAArg during protein synthesis. Scintillation proximity assays (SPA) were adapted to the aminoacylation assay and used to screen, one natural compound library (800) and one synthetic compound library (890) to identify inhibitors of the activity of ArgRS. Five compounds were identified which inhibited greater than 50% of enzymatic activity, two of these compounds (BT04F10 and BT11F03) exhibited promising MICs against Gram+ bacteria and moderate activity against Gram- …

Expression, Purification, Enzymatic And Inhibition Profile Of Brugia Malayi Dihydrofolate Reductase, Romy Perez-Abraham

Theses, Dissertations and Culminating Projects

Dihydrofolate reductase (DHFR) is an essential enzyme that plays an important role in the production of cofactors that are required in deoxyribonucleic acid (DNA) synthesis. The literature suggests that DHFR is a potential drug target for the elimination of the parasitic worm, B. malayi. B. malayi is one of the causative parasites of lymphatic filariasis, a globally neglected tropical disease. In this study, we expressed and purified B. malayi DHFR. Expression was carried out in E. coli with a His6-tagged construct, and purification was achieved through affinity chromatography using a special strain of E. coli cells called “LOBSTR.” The resulting …

Computing The Optimal Path In Stochastic Dynamical Systems, Martha Bauver

Theses, Dissertations and Culminating Projects

In stochastic systems, one is often interested in finding the optimal path that maximizes the probability of escape from a metastable state or of switching between metastable states. Even for simple systems it may be impossible to find an analytic form of the optimal path, and in high-dimensional systems, this is almost always the case. The optimal path is of great importance, since it represents the most likely path of a rare switching or escape event. For instance, the optimal path for an infectious disease model represents a switching from an infectious state to the extinction of the disease within …

Ecological Niche Modeling Of The North American Giant Salamander: Predicting Current And Future Potential Distributions And Examining Environmental Influences, Selena S. Roark

Electronic Theses and Dissertations

North American Giant Salamanders (Cryptobranchus alleganiensis), commonly known as hellbenders, have been experiencing a population decline for decades due to human influences, such as pollution and habitat destruction. Many efforts are underway to save the hellbender but their entire potential geographical range has not been well-studied. Currently, hellbender populations are delineated by county boundaries and are on the International Union for Conservation of Nature Red List. The Genetic Algorithm for Rule-set Production, an Ecological Niche Model, was used to model the current hellbender potential distribution at a macro-scale under two different environmental scenarios. Additionally, future potential distributions were …

A Spatiotemporal Mountain Pine Beetle Outbreak Model Predicting Severity, Cycle Period, And Invasion Speed, Jacob P. Duncan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The mountain pine beetle (MPB, Dendroctonus ponderosae), a tree-killing bark beetle, has historically been part of the normal disturbance regime in lodgepole pine (Pinus contorta) forests. In recent years, warm winters and summers have allowed MPB populations to achieve synchronous emergence and successful attacks, resulting in widespread population outbreaks and resultant tree mortality across western North America. We develop an age-structured forest demographic model that incorporates temperature-dependent MPB infestations: the Susceptible-Infested-Juvenile (SIJ) model. Stability of equilibria is analyzed as a function of population growth rates, and indicates the existence of periodic outbreaks that intensify as growth rates …

Synthesis, Structure-Activity Relationship Study, And Mode Of Action Study Of 1,4-Naphthoquinone Based Anticancer And Antimicrobial Agents, Jaya P. Shrestha

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The first three projects involve the synthesis and the mode of action study of 1,4-naphthoquinone based anticancer agents. These anticancer agents are highly potent against a wide range of cancer cell lines. These compounds showed ~8-fold selectivity towards the lung cancer cell line than the normal cell line. We also studied the mode of action and observed that generation of reactive oxygen species is the primary mode of action.

The final project involves the synthesis of multi-cationic antimicrobial agents. These compounds are active against both bacteria and fungi. These compounds are very easy to synthesize and can be scaled up …

Infinite Color Urn Models., Debleena Thacker Dr.

Doctoral Theses

In recent years, there has been a wide variety of work on random reinforcement models of various kinds. Urn models form an important class of random reinforcement models, with numerous applications in engineering and informatics and bioscience. In recent years there have been several works on different kinds of urn models and their generalizations. For occupancy urn models, where one considers recursive addition of balls into finite or infinite number of boxes, there are some works which introduce models with infinitely many colors, typically represented by the boxes.As observed in [51], the earliest mentions of urn models are in the …

The Firece Green Fire: Vol. 6 Issue 23, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.

Developing Molecular Tools For Diagnosis Of Human Ehrlichiosis, Megan Mears

GS4 Student Scholars Symposium

Background: Ehrlichia chaffeensis, E. ewingii, E. muris and E. canis are known to cause febrile illnesses in humans and dogs. These pathogens are transmitted by ticks, and infection is established following invasion of the human or dog white blood cells. Ehrlichia chaffeensis infections of humans have a fatality rate up to 5%. Ehrlichia ewingii displays antigenic cross-reactivity with E. chaffeensis; however, laboratory case confirmation is difficult because E. ewingii is not cultivable so antigens and genetic data are hard to acquire. Our project will develop approaches and tools to characterize E. ewingii surface protein gene homologous to the major 120 …

Intramolecular Cross-Linking Of Beta Subunits And Pegylation Of Bovine Stroma Free Hemoglobin For Use As A Hemoglobin Based Oxygen Carrier, Gil Salazar

GS4 Student Scholars Symposium

Purified Bovine Stroma-Free Hemoglobin's (BSFHb) two beta subunits where intramolecularly cross-linked (BXLHb) using bis(3,5-dibromosalicyl) fumarate (DBBF) and further modified with Polyethylene glycol (BPEGXLHb) for possible use as a Hemoglobin Based Oxygen Carrier (HBOC). Each stage of modification was characterized by size exclusion chromatography and fluorescence methods. We prepared several different molar ratios of DBBF and BSFHb to acquire the highest yield of BXLHb. Cross-linking of the beta subunits will stabilize the whole Hb tetramer from dissociation and prevent unwanted degradation of the HBOC. We prepared a sample modified with PEG (PEGylation) that had a molecular weight of 5kDa. PEGylation increases …

Mathematical Models For Infectious Disease Transmission With Stochastic Simulation Of Measles Outbreaks, Valerie Welty

Honors College Theses

As they are the leading cause of death among children and adolescents worldwide, it is of extreme importance to control the spread of infectious diseases. Information gained from mathematical modeling of these events often proves quite useful in establishing policy decisions to accomplish this goal. Human behavior, however, is quite difficult to recreate when using equations with pre-determined results, such as deterministic differential equations often used with epidemic models. Because of this, the focus of the research was to create a simulation of an outbreak, specifically of measles, by using an imaginary population experiencing simulated stochastic events on a discrete …

Wright State University's Celebration Of Research, Scholarship And Creative Activities Book Of Abstracts From Friday, April 15, 2016, Wright State University Office Of Undergraduate Research And Stemm Activities

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

The student abstract booklet is a compilation of abstracts from students' oral and poster presentations at Wright State University's Annual Celebration of Research, Scholarship and Creative Activities on April 15, 2016.

The Firece Green Fire: Vol. 6 Issue 22, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.

The Role Of Mathematical Modeling In Designing And Evaluating Antimicrobial Stewardship Programs, Lester Caudill, Joanna R. Wares

Department of Math & Statistics Faculty Publications

Antimicrobial agent effectiveness continues to be threatened by the rise and spread of pathogen strains that exhibit drug resistance. This challenge is most acute in healthcare facilities where the well-established connection between resistance and sub-optimal antimicrobial use has prompted the creation of antimicrobial stewardship programs (ASPs). Mathematical models offer tremendous potential for serving as an alternative to controlled human experimentation for assessing the effectiveness of ASPs. Models can simulate controlled randomized experiments between groups of virtual patients, some treated with the ASP measure under investigation, and some without. By removing the limitations inherent in human experimentation, including health risks, study …

The Role Of Mathematical Modeling In Designing And Evaluating Antimicrobial Stewardship Programs, Lester Caudill, Joanna R. Wares

Department of Math & Statistics Faculty Publications

Antimicrobial agent effectiveness continues to be threatened by the rise and spread of pathogen strains that exhibit drug resistance. This challenge is most acute in healthcare facilities where the well-established connection between resistance and suboptimal antimicrobial use has prompted the creation of antimicrobial stewardship programs (ASPs). Mathematical models offer tremendous potential for serving as an alternative to controlled human experimentation for assessing the effectiveness of ASPs. Models can simulate controlled randomized experiments between groups of virtual patients, some treated with the ASP measure under investigation, and some without. By removing the limitations inherent in human experimentation, including health risks, study …

Combatting Biases: Illusory Imagery In Us News Coverage On Central American Immigration, Katharine Poor

Butler Journal of Undergraduate Research

This paper comprises of original research and analysis of contemporary news media discourse surrounding Central American immigration in the United States. Subjects of study included more than 50 news articles, images, and videos from a variety of major politically-unaffiliated news outlets for English-speaking audiences. Rhetoric was analyzed in representations of the Central American immigration “crisis” that sparked a trend of media coverage in 2014, as well as several articles that covered events leading up to the “crisis.” Common rhetorical analogies ascertained through media analyses include the representation of immigrants as aliens, diseases, parasites, floods, criminals, natural disasters, terrorists, and drug …

Costumbres, Creencias, Y “Lo Normal”: A Biocultural Study On Changing Prenatal Dietary Practices In A Rural Tourism Community In Costa Rica, Allison Rachel Cantor

USF Tampa Graduate Theses and Dissertations

This study explores the relationship between tourism, the nutrition transition, and prenatal dietary practices in the Monteverde Zone, Costa Rica. This rural tourism community, located in the central highlands of Costa Rica, has seen rapid growth and development since the tourism boom in the early 1990s, leading to changes in the local food system and increased food insecurity. This investigation added to this work by identifying the ways that prenatal dietary practices have shifted over time in the context of increased tourism and the concomitant nutrition transition, and by describing the relationship between food insecurity and nutritional status among pregnant …

Comparison Of Growth Rates In Two Captive Bred Species Of Atelopus (Anura; Bufonidae), At El Valle Amphibian Conservation Center, Cecile Avery

Independent Study Project (ISP) Collection

Since their evolution, amphibians have managed to survive four mass extinctions. But today’s amphibians are now facing severe decline due to a plethora of causes including habitat destruction, climate change, pathogens, and pollution. Of all the possible causes of decline and extinction of amphibian populations, one of the most startling has been the effect of Batrachochytrium dendrobatidis (Bd), or chytrid fungus. It was decided that rapid action was needed to preserve the amphibian populations in the area, since it was clear that current in situ conservation methods were ineffective against Bd. EVACC, the El Valle Amphibian Conservation Center, was created …

An Adaptive Visual Learning Approach For Waterborne Disease Prevention In Rural West Africa, Jonathan Le Mar Oglesby

Masters Theses & Specialist Projects

Depleted water supplies, along with industrial and human waste, are driving a world water crisis that poses a growing risk to food markets, energy production, political stability, and human health (Global Water Security 2012). One obvious example of the this crisis is the more than 1 billion people who obtain their drinking water from contaminated sources (WHO/UNICEF 2006; Clasen et al. 2008). With a projected increase of 1.3 billion people between now and 2050, Africa will add more to the global population than any other world region (Haub and Kaneda 2013). For this research, visual learning design factors were incorporated …