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Full-Text Articles in Physical Sciences and Mathematics

Information Feedback Delays Within Epidemic Models And Their Effect On Model Dynamics., Maria K. Bouka, Christopher Strickland Dr May 2024

Information Feedback Delays Within Epidemic Models And Their Effect On Model Dynamics., Maria K. Bouka, Christopher Strickland Dr

Biology and Medicine Through Mathematics Conference

No abstract provided.


Analytical Approach For Monitoring The Behavior Of Patients With Pancreatic Adenocarcinoma At Different Stages As A Function Of Time, Aditya Chakaborty Dr, Chris P. Tsokos Dr May 2023

Analytical Approach For Monitoring The Behavior Of Patients With Pancreatic Adenocarcinoma At Different Stages As A Function Of Time, Aditya Chakaborty Dr, Chris P. Tsokos Dr

Biology and Medicine Through Mathematics Conference

No abstract provided.


Generalized Differential Equation Models For Disease Interventions: A Novel Approach For Predicting Sexually Transmitted Disease Outbreaks, Scott Greenhalgh May 2023

Generalized Differential Equation Models For Disease Interventions: A Novel Approach For Predicting Sexually Transmitted Disease Outbreaks, Scott Greenhalgh

Biology and Medicine Through Mathematics Conference

No abstract provided.


Modeling The Dynamics Of Alcohol-Marijuana Co-Abuse In Virginia, Ana L. Vivas-Barber, James Tipton, Sujan Pant, Anne Fernando May 2023

Modeling The Dynamics Of Alcohol-Marijuana Co-Abuse In Virginia, Ana L. Vivas-Barber, James Tipton, Sujan Pant, Anne Fernando

Biology and Medicine Through Mathematics Conference

No abstract provided.


Relative Efficacy Of Resource Constrained Forward And Backward Contact Tracing In An Open Population, Nicholas Roberts May 2023

Relative Efficacy Of Resource Constrained Forward And Backward Contact Tracing In An Open Population, Nicholas Roberts

Biology and Medicine Through Mathematics Conference

No abstract provided.


Epidemiological Assessment Of Wolbachia-Based Biocontrol For Reduction Of Dengue Morbidity, Olga Vasilieva, Oscar E. Escobar, Hector J. Martinez, Pierre-Alexandre Bliman, Yves Dumont May 2022

Epidemiological Assessment Of Wolbachia-Based Biocontrol For Reduction Of Dengue Morbidity, Olga Vasilieva, Oscar E. Escobar, Hector J. Martinez, Pierre-Alexandre Bliman, Yves Dumont

Biology and Medicine Through Mathematics Conference

No abstract provided.


Estimating Weighted Panel Sizes For Primary Care Providers: An Assessment Of Clustering And Novel Methods Of Panel Size Estimation On Electronic Medical Records, Martin A. Lavallee Jan 2022

Estimating Weighted Panel Sizes For Primary Care Providers: An Assessment Of Clustering And Novel Methods Of Panel Size Estimation On Electronic Medical Records, Martin A. Lavallee

Theses and Dissertations

Primary Care is on the frontlines of healthcare, thus they see the most diverse set of patients. In order to achieve high functioning primary care, a practice must establish empanelment, the pairing of patients to providers. Enumeration of empanelment, or estimating panel sizes, helps ensure that the demands of the patients demand the supply of providers and optimize the balance of primary care resources to improve quality of care. Further we can adjust panel sizes by using patient-level data on healthcare utilization and complexity extracted from the electronic medial record to determine the amount of care or burden of work …


Mathematical Models Of Infection Prevention Programs In Hospital Settings, Kelly A. Reagan Jan 2022

Mathematical Models Of Infection Prevention Programs In Hospital Settings, Kelly A. Reagan

Theses and Dissertations

Hospitals play a vital role in providing for the healthcare needs of a community. Patients can develop hospital-acquired infections (HAIs) during their hospitalization due to exposure to foreign bacteria, viruses, and fungi. Infection prevention programs target and reduce HAIs, but implementing the infection prevention programs often comes with a cost. The goal of my research is to use mathematical models to quantify the impact of infection prevention programs on cases of HAIs and total healthcare costs. First, I use a Markov chain model to quantify how one infection prevention program reduces general HAIs in the hospital. Then, I calculate the …


Behavioral Screening And Chiral Bioanalysis Of Emerging Stimulant-Type Drugs In Rats, Tyson R. Baird Jan 2022

Behavioral Screening And Chiral Bioanalysis Of Emerging Stimulant-Type Drugs In Rats, Tyson R. Baird

Theses and Dissertations

The epidemic of drug use in the United States and elsewhere in the world has resulted in tragic loss of life and substantial economic costs. Novel psychoactive substances (NPS) are one of the contributors to this problem, and the lack of information about many of these drugs compounds their risk. This dissertation proposes a strategy to use intracranial self-stimulation (ICSS) as a behavioral screening tool to assess emerging drugs of abuse for their abuse potential in order to generate a proactive threat assessment. A series of stimulant-type drugs including methcathinone, α-pyrrolidinohexanophenone (α-PHP), cocaine, and the phenyltropane analogs of cocaine WIN35428 …


A Participatory Group Process To Collect And Disseminate Covid-19 Needs Assessment Data, Areebah Ahmed Jan 2022

A Participatory Group Process To Collect And Disseminate Covid-19 Needs Assessment Data, Areebah Ahmed

Undergraduate Research Posters

The Richmond, VA COVID-19 Needs Assessment Survey (RVA CoNA) was created in March 2020 to identify behaviors and needs related to COVID-19 in Richmond area adults ages 18 and over. Results are being used to inform support, strategic efforts, and educational outreach of local community organizations. The purpose of this study is to (1) summarize the process used to develop the RVA CoNA, (2) summarize preliminary survey results from a second phase of data collection as well as initial feedback from community partners, and (3) summarize initial conclusions and results dissemination strategies.Community partners and researchers at Virginia Commonwealth University jointly …


Modeling Longitudinal Change In Cervical Length Across Pregnancy, Hope M. Wolf, Shawn J. Latendresse, Jerome F. Strauss Iii, Timothy P. York Jan 2021

Modeling Longitudinal Change In Cervical Length Across Pregnancy, Hope M. Wolf, Shawn J. Latendresse, Jerome F. Strauss Iii, Timothy P. York

Graduate Research Posters

Introduction: A short cervix (cervical length < 25 mm) in the mid-trimester (18 to 24 weeks) of pregnancy is a powerful predictor of spontaneous preterm delivery (gestational age at delivery < 37 weeks). Although the biological mechanisms of cervical remodeling have been the subject of extensive investigation, very little is known about the rate of change in cervical length over the course of a pregnancy, or the extent to which rapid cervical shortening increases maternal risk for spontaneous preterm delivery.

Methods: A cohort of 5,160 unique women carrying 5,971 singleton pregnancies provided two or more measurements of cervical length during pregnancy. Cervical length was measured in millimeters using a transvaginal 12-3 MHz ultrasound endocavity probe (SuperSonic Imagine). Maternal characteristics, including relevant medical history and birth outcome data, were collected for each participant. Gestational age at delivery was measured from the first day of each woman’s last menstrual period and confirmed by ultrasound. Repeated measurements of cervical length during pregnancy were modeled as a longitudinal, multilevel growth curve in MPlus. A three-level variance structure was …


A Deep Learning U-Net For Detecting And Segmenting Liver Tumors, Vidhya Cardozo Jan 2021

A Deep Learning U-Net For Detecting And Segmenting Liver Tumors, Vidhya Cardozo

Theses and Dissertations

Visualization of liver tumors on simulation CT scans is challenging even with contrast-enhancement, due to the sensitivity of the contrast enhancement to the timing of the CT acquisition. Image registration to magnetic resonance imaging (MRI) can be helpful for delineation, but differences in patient position, liver shape and volume, and the lack of anatomical landmarks between the two image sets makes the task difficult. This study develops a U-Net based neural network for automated liver and tumor segmentation for purposes of radiotherapy treatment planning. Non-contrast simulation based abdominal CT axial scans of 52 patients with primary liver tumors were utilized. …


Saving Lives, Limbs And Healthcare Costs]{Saving Lives, Limbs And Healthcare Costs: Quantifying The Impact Of Chg Bathing And Effective Leadership On The Reduction Of Hospital-Acquired Infections, Kelly A. Reagan May 2020

Saving Lives, Limbs And Healthcare Costs]{Saving Lives, Limbs And Healthcare Costs: Quantifying The Impact Of Chg Bathing And Effective Leadership On The Reduction Of Hospital-Acquired Infections, Kelly A. Reagan

Biology and Medicine Through Mathematics Conference

No abstract provided.


The Role Of Variation In Mate Choice And Wolbachia Infection On Aedes Aegypti Population Dynamics, Bernardo Ameneyro May 2020

The Role Of Variation In Mate Choice And Wolbachia Infection On Aedes Aegypti Population Dynamics, Bernardo Ameneyro

Biology and Medicine Through Mathematics Conference

No abstract provided.


Characterizing The Permanence And Stationary Distribution For A Family Of Malaria Stochastic Models, Divine Wanduku May 2019

Characterizing The Permanence And Stationary Distribution For A Family Of Malaria Stochastic Models, Divine Wanduku

Biology and Medicine Through Mathematics Conference

No abstract provided.


Investigating Drivers Of Dengue Emergence In Cordoba, Argentina, Michael Andrew Robert, Rachel Sippy, Anna M. Stewart-Ibarra, Rebecca C. Christofferson, Helen J. Wearing, Elizabet L. Estallo May 2019

Investigating Drivers Of Dengue Emergence In Cordoba, Argentina, Michael Andrew Robert, Rachel Sippy, Anna M. Stewart-Ibarra, Rebecca C. Christofferson, Helen J. Wearing, Elizabet L. Estallo

Biology and Medicine Through Mathematics Conference

No abstract provided.


Parameter Identification For A Stochastic Seirs Epidemic Model: Case Study Influenza, Olusegun M. Otunuga, Anna Mummert May 2019

Parameter Identification For A Stochastic Seirs Epidemic Model: Case Study Influenza, Olusegun M. Otunuga, Anna Mummert

Biology and Medicine Through Mathematics Conference

No abstract provided.


Ebola: Impact Of Hospital's Admission Policy In An Overwhelmed Scenario, Mondal H. Zahid May 2019

Ebola: Impact Of Hospital's Admission Policy In An Overwhelmed Scenario, Mondal H. Zahid

Biology and Medicine Through Mathematics Conference

No abstract provided.


A Study Of Pair Formation Disease Models With A Two Phase Infection, Berlinda Rosa Batista May 2019

A Study Of Pair Formation Disease Models With A Two Phase Infection, Berlinda Rosa Batista

Biology and Medicine Through Mathematics Conference

No abstract provided.


Decoys And Dilution: The Impact Of Incompetent Hosts On Prevalence Of Chagas Disease, Mondal H. Zahid May 2019

Decoys And Dilution: The Impact Of Incompetent Hosts On Prevalence Of Chagas Disease, Mondal H. Zahid

Biology and Medicine Through Mathematics Conference

No abstract provided.


Machine Learning Methods To Forecast Temporal Pattern Of Aedes Mosquito Species Using Meteorological Variables In Ontario, Canada, Mohammad A. Al-Mamun, Ernest O. Asare May 2019

Machine Learning Methods To Forecast Temporal Pattern Of Aedes Mosquito Species Using Meteorological Variables In Ontario, Canada, Mohammad A. Al-Mamun, Ernest O. Asare

Biology and Medicine Through Mathematics Conference

No abstract provided.


2nd Tier Assay For The Detection Of Congenital Adrenal Hyperplasia By Virginia’S Newborn Screening Laboratory: Steroid Profile By Hplc-Ms/Ms, Christopher E. Nixon Jan 2019

2nd Tier Assay For The Detection Of Congenital Adrenal Hyperplasia By Virginia’S Newborn Screening Laboratory: Steroid Profile By Hplc-Ms/Ms, Christopher E. Nixon

Theses and Dissertations

Congenital Adrenal Hyperplasia (CAH) encompasses several disorders related to disruptions in the adrenal steroid production pathway. These disruptions may cause virilization of the external female sex organs, incorrect gender assignment, precocious puberty, and in the most severe form, may cause life-threatening salt wasting and adrenal crisis if not detected and treated early in the newborn period.

17α-Hydroxyprogesterone (17-OHP) is the primary target for immunofluorescence detection of CAH from dried blood spots in newborn screening (NBS). Unfortunately, current immunoassay techniques for the detection of CAH suffer from high false positive rates. The primary factors contributing to false positive determinations can include …


Penalized Mixed-Effects Ordinal Response Models For High-Dimensional Genomic Data In Twins And Families, Amanda E. Gentry Jan 2018

Penalized Mixed-Effects Ordinal Response Models For High-Dimensional Genomic Data In Twins And Families, Amanda E. Gentry

Theses and Dissertations

The Brisbane Longitudinal Twin Study (BLTS) was being conducted in Australia and was funded by the US National Institute on Drug Abuse (NIDA). Adolescent twins were sampled as a part of this study and surveyed about their substance use as part of the Pathways to Cannabis Use, Abuse and Dependence project. The methods developed in this dissertation were designed for the purpose of analyzing a subset of the Pathways data that includes demographics, cannabis use metrics, personality measures, and imputed genotypes (SNPs) for 493 complete twin pairs (986 subjects.) The primary goal was to determine what combination of SNPs and …


Analyzing Sexual Transmission In The Spread Of The Zika Virus In Colombia, Victoria M. Kelley May 2017

Analyzing Sexual Transmission In The Spread Of The Zika Virus In Colombia, Victoria M. Kelley

Biology and Medicine Through Mathematics Conference

No abstract provided.


Control Policies And Sensitivity Analysis In A Cutaneous Leishmaniasis Model: A Case Study In Cusco Region, Peru., Rocio M. Caja-Rivera, Ignacio Barradas May 2017

Control Policies And Sensitivity Analysis In A Cutaneous Leishmaniasis Model: A Case Study In Cusco Region, Peru., Rocio M. Caja-Rivera, Ignacio Barradas

Biology and Medicine Through Mathematics Conference

No abstract provided.


A Mathematical Model Of The Spread Of Dengue Fever Incorporating Mobility, Kelly A. Reagan May 2016

A Mathematical Model Of The Spread Of Dengue Fever Incorporating Mobility, Kelly A. Reagan

Biology and Medicine Through Mathematics Conference

No abstract provided.


Dynamics Of Two Pathogens In A Single Tick Population, Alexis White May 2016

Dynamics Of Two Pathogens In A Single Tick Population, Alexis White

Biology and Medicine Through Mathematics Conference

No abstract provided.


General Models For Ecological Drivers Of Poverty, Calistus Ngeh Ngonghala May 2016

General Models For Ecological Drivers Of Poverty, Calistus Ngeh Ngonghala

Biology and Medicine Through Mathematics Conference

No abstract provided.


Provision Of Hospital-Based Palliative Care And The Impact On Organizational And Patient Outcomes, Marisa L. Roczen Jan 2016

Provision Of Hospital-Based Palliative Care And The Impact On Organizational And Patient Outcomes, Marisa L. Roczen

Theses and Dissertations

Hospital-based palliative care services aim to streamline medical care for patients with chronic and potentially life-limiting illnesses by focusing on individual patient needs, efficient use of hospital resources, and providing guidance for patients, patients’ families and clinical providers toward making optimal decisions concerning a patient’s care. This study examined the nature of palliative care provision in U.S. hospitals and its impact on selected organizational and patient outcomes, including hospital costs, length of stay, in-hospital mortality, and transfer to hospice. Hospital costs and length of stay are viewed as important economic indicators. Specifically, lower hospital costs may increase a hospital’s profit …