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Biological And Practical Implications Of Genome-Wide Association Study Of Schizophrenia Using Bayesian Variable Selection, Benazir Rowe, Xiangning Chen, Zuoheng Wang, Jingchun Chen, Amei Amei 2019 University of Nevada, Las Vegas

Biological And Practical Implications Of Genome-Wide Association Study Of Schizophrenia Using Bayesian Variable Selection, Benazir Rowe, Xiangning Chen, Zuoheng Wang, Jingchun Chen, Amei Amei

School of Medicine Faculty Publications

Genome-wide association studies (GWAS) have identified over 100 loci associated with schizophrenia. Most of these studies test genetic variants for association one at a time. In this study, we performed GWAS of the molecular genetics of schizophrenia (MGS) dataset with 5334 subjects using multivariate Bayesian variable selection (BVS) method Posterior Inference via Model Averaging and Subset Selection (piMASS) and compared our results with the previous univariate analysis of the MGS dataset. We showed that piMASS can improve the power of detecting schizophrenia-associated SNPs, potentially leading to new discoveries from existing data without increasing the sample size. We tested SNPs in ...


Introduction To The Special Issue On Reproducibility In Neuroimaging, Russell A. Poldrack, Kirstie Whitaker, David N. Kennedy 2019 Stanford University

Introduction To The Special Issue On Reproducibility In Neuroimaging, Russell A. Poldrack, Kirstie Whitaker, David N. Kennedy

Open Access Publications by UMMS Authors

The last decade has seen increasing attention to the problem of scientific reproducibility, across a broad range of scientific fields (Camerer et al., 2016;Morrison, 2014;Open Science Collaboration, 2015). Within the field of neuroimaging, there has been a particular focus on issues of analytic variability (Bowring et al., 2019;Carp, 2012) statistical power (Button et al., 2013;Poldrack et al., 2017), and test-retest reliability (Bennett and Miller, 2013), all of which have raised alarms regarding the potential for irreproducible results. In addition, failed replications (Boekel et al., 2015;Dinga et al., 2019) and meta-analytic null results (Müller et al ...


Conditional Survival Analysis For Concrete Bridge Decks, Azam Nabizadeh, Habib Tabatabai, Mohammad A. Tabatabai 2019 University of Wisconsin-Milwaukee

Conditional Survival Analysis For Concrete Bridge Decks, Azam Nabizadeh, Habib Tabatabai, Mohammad A. Tabatabai

Civil and Environmental Engineering Faculty Articles

Bridge decks are a significant factor in the deterioration of bridges, and substantially affect long-term bridge maintenance decisions. In this study, conditional survival (reliability) analysis techniques are applied to bridge decks to evaluate the age at the end of service life using the National Bridge Inventory records. As bridge decks age, the probability of survival and the expected service life would change. The additional knowledge gained from the fact that a bridge deck has already survived a specific number of years alters (increases) the original probability of survival at subsequent years based on the conditional probability theory. The conditional expected ...


Post-Acquisition Processing Confounds In Brain Volumetric Quantification Of White Matter Hyperintensities, Ahmed A. Bahrani, Omar M. Al-Janabi, Erin L. Abner, Shoshana H. Bardach, Richard J. Kryscio, Donna M. Wilcock, Charles D. Smith, Gregory A. Jicha 2019 University of Kentucky

Post-Acquisition Processing Confounds In Brain Volumetric Quantification Of White Matter Hyperintensities, Ahmed A. Bahrani, Omar M. Al-Janabi, Erin L. Abner, Shoshana H. Bardach, Richard J. Kryscio, Donna M. Wilcock, Charles D. Smith, Gregory A. Jicha

Neurology Faculty Publications

BACKGROUND: Disparate research sites using identical or near-identical magnetic resonance imaging (MRI) acquisition techniques often produce results that demonstrate significant variability regarding volumetric quantification of white matter hyperintensities (WMH) in the aging population. The sources of such variability have not previously been fully explored.

NEW METHOD: 3D FLAIR sequences from a group of randomly selected aged subjects were analyzed to identify sources-of-variability in post-acquisition processing that can be problematic when comparing WMH volumetric data across disparate sites. The methods developed focused on standardizing post-acquisition protocol processing methods to develop a protocol with less than 0.5% inter-rater variance.

RESULTS: A ...


Inferring A Consensus Problem List Using Penalized Multistage Models For Ordered Data, Philip S. Boonstra, John C. Krauss 2019 The University Of Michigan

Inferring A Consensus Problem List Using Penalized Multistage Models For Ordered Data, Philip S. Boonstra, John C. Krauss

The University of Michigan Department of Biostatistics Working Paper Series

A patient's medical problem list describes his or her current health status and aids in the coordination and transfer of care between providers, among other things. Because a problem list is generated once and then subsequently modified or updated, what is not usually observable is the provider-effect. That is, to what extent does a patient's problem in the electronic medical record actually reflect a consensus communication of that patient's current health status? To that end, we report on and analyze a unique interview-based design in which multiple medical providers independently generate problem lists for each of three ...


Enhancing Timeliness Of Drug Overdose Mortality Surveillance: A Machine Learning Approach, Patrick J. Ward, Peter J. Rock, Svetla Slavova, April M. Young, Terry L. Bunn, Ramakanth Kavuluru 2019 University of Kentucky

Enhancing Timeliness Of Drug Overdose Mortality Surveillance: A Machine Learning Approach, Patrick J. Ward, Peter J. Rock, Svetla Slavova, April M. Young, Terry L. Bunn, Ramakanth Kavuluru

Kentucky Injury Prevention and Research Center Faculty Publications

BACKGROUND: Timely data is key to effective public health responses to epidemics. Drug overdose deaths are identified in surveillance systems through ICD-10 codes present on death certificates. ICD-10 coding takes time, but free-text information is available on death certificates prior to ICD-10 coding. The objective of this study was to develop a machine learning method to classify free-text death certificates as drug overdoses to provide faster drug overdose mortality surveillance.

METHODS: Using 2017–2018 Kentucky death certificate data, free-text fields were tokenized and features were created from these tokens using natural language processing (NLP). Word, bigram, and trigram features were ...


Choosing Clinical Variables For Risk Stratification Post-Acute Coronary Syndrome, Paul D. Myers, Wei Huang, Frederick A. Anderson Jr., Collin M. Stultz 2019 Massachusetts Institute of Technology

Choosing Clinical Variables For Risk Stratification Post-Acute Coronary Syndrome, Paul D. Myers, Wei Huang, Frederick A. Anderson Jr., Collin M. Stultz

Open Access Publications by UMMS Authors

Most risk stratification methods use expert opinion to identify a fixed number of clinical variables that have prognostic significance. In this study our goal was to develop improved metrics that utilize a variable number of input parameters. We first used Bootstrap Lasso Regression (BLR) - a Machine Learning method for selecting important variables - to identify a prognostic set of features that identify patients at high risk of death 6-months after presenting with an Acute Coronary Syndrome. Using data derived from the Global Registry of Acute Coronary Events (GRACE) we trained a logistic regression model using these features and evaluated its performance ...


Quantifying Pollen Traits To Build A Mathematical Model Of Pollen Competition - A Biologist's Perspective, Rob Swanson, Alex Capaldi 2019 Valparaiso University

Quantifying Pollen Traits To Build A Mathematical Model Of Pollen Competition - A Biologist's Perspective, Rob Swanson, Alex Capaldi

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


Classification Of Coronary Artery Disease In Non-Diabetic Patients Using Artificial Neural Networks, Demond Handley 2019 Illinois State University

Classification Of Coronary Artery Disease In Non-Diabetic Patients Using Artificial Neural Networks, Demond Handley

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


What About The Environment?: Exploring The Neglected Third Dimension Of Antimicrobial Resistance, Paige E. Montfort 2019 SIT Study Abroad

What About The Environment?: Exploring The Neglected Third Dimension Of Antimicrobial Resistance, Paige E. Montfort

Independent Study Project (ISP) Collection

Antimicrobial resistance (AMR) is one of the most urgent and complex health risks of our time, with links to human health, animal health, and the environment. The majority of research and policy related to AMR, however, has been dedicated to human and animal health. The third dimension — the environment — has been relatively neglected. Conversations about this problem have begun, but gaps in understanding remain. This study explores the key barriers that have hindered developments related to the environmental aspect of AMR and some of the solutions that have begun to or could be utilized to overcome these barriers.

A grounded ...


36 Years After The Species' Mass-Mortality: Diadema Antillarum Test Sizes, Population Densities, And Substrate Preferences In Three Guna Yala Reefs Near Wichub Wala Island, Bimini Horstmann 2019 SIT Study Abroad

36 Years After The Species' Mass-Mortality: Diadema Antillarum Test Sizes, Population Densities, And Substrate Preferences In Three Guna Yala Reefs Near Wichub Wala Island, Bimini Horstmann

Independent Study Project (ISP) Collection

In January 1983, a waterborne pathogen beginning near the Atlantic Panama Canal entrance caused history's largest recorded marine animal die-off, wiping out 95-99% of Diadema antillarum populations throughout the Caribbean. D. antillarum, the long-spined sea urchin, is a keystone herbivore in coral reefs and its decreased densities have caused many reefs to suffer macroalgal phase shifts. Modest recovery of this species has been documented in some Caribbean locations, but reefs in Guna Yala, Panama continued to experience population decline. This study investigates density, test size, and substrate preferences of D. antillarum in three shallow coral reef areas to update ...


Socioemotional Selectivity And Psychological Health In Amyotrophic Lateral Sclerosis Patients And Caregivers: A Longitudinal, Dyadic Analysis, Suzanne C. Segerstrom, Edward J. Kasarskis, David W. Fardo, Philip M. Westgate 2019 University of Kentucky

Socioemotional Selectivity And Psychological Health In Amyotrophic Lateral Sclerosis Patients And Caregivers: A Longitudinal, Dyadic Analysis, Suzanne C. Segerstrom, Edward J. Kasarskis, David W. Fardo, Philip M. Westgate

Psychology Faculty Publications

Objective: Socioemotional selectivity theory predicts that as the end of life approaches, goals and resources that provide immediate, hedonic reward become more important than those that provide delayed rewards. This study tested whether these goal domains differentially affected psychological health in the context of marital dyads in which one partner had been diagnosed with amyotrophic lateral sclerosis (ALS), a life-limiting disease.

Design: ALS patients (N = 102) being treated in three multidisciplinary clinics and their spouses (N = 100) reported their loneliness, financial worry and psychological health every 3 months for up to 18 months.

Main Outcome Measure: Psychological health composite.

Results ...


Acute Systemic Inflammatory Response To Lipopolysaccharide Stimulation In Pigs Divergently Selected For Residual Feed Intake, Haibo Liu, Kristina M. Feye, Yet T. Nguyen, Anoosh Rakhshandeh, Crystal L. Loving, Jack C. M. Sekkers, Nicholas K. Gabler, Christopher K. Tuggle 2019 Old Dominion University

Acute Systemic Inflammatory Response To Lipopolysaccharide Stimulation In Pigs Divergently Selected For Residual Feed Intake, Haibo Liu, Kristina M. Feye, Yet T. Nguyen, Anoosh Rakhshandeh, Crystal L. Loving, Jack C. M. Sekkers, Nicholas K. Gabler, Christopher K. Tuggle

Mathematics & Statistics Faculty Publications

Background: It is unclear whether improving feed efficiency by selection for low residual feed intake (RFI) compromises pigs’ immunocompetence. Here, we aimed at investigating whether pig lines divergently selected for RFI had different inflammatory responses to lipopolysaccharide (LPS) exposure, regarding to clinical presentations and transcriptomic changes in peripheral blood cells.

Results: LPS injection induced acute systemic inflammation in both the low-RFI and high-RFI line (n = 8 per line). At 4 h post injection (hpi), the low-RFI line had a significantly lower (p= 0.0075) mean rectal temperature compared to the high-RFI line. However, no significant differences in complete blood count ...


From Traps To Snapshots: Examining The Ecology Of Feral Predators And Native Small Mammals In Southeastern Australia Through Case Studies Of Two Faunal Sampling Methods, Katherine Karson 2019 SIT Study Abroad

From Traps To Snapshots: Examining The Ecology Of Feral Predators And Native Small Mammals In Southeastern Australia Through Case Studies Of Two Faunal Sampling Methods, Katherine Karson

Independent Study Project (ISP) Collection

The red fox (Vulpes vulpes) and feral cat (Felis catus) are introduced mesopredators that significantly threaten native small mammal species in Australia. For decades, environmental managers have attempted to mitigate the effects of these introduced species. However, ecosystems are highly complex, making it difficult to assess the impacts of feral predators on communities of native fauna independent of other disturbances such as fire regime and habitat fragmentation. Cost-effective ecological monitoring programs are imperative for evaluating threats to native species and informing environmental decisions. New technology has become increasingly present in wildlife monitoring, and camera trapping has provided an alternative to ...


An Analysis Of The Rajasthan Public Health System’S Response To The 2019 Dengue Insurgence, Luke Bryan 2019 SIT Study Abroad

An Analysis Of The Rajasthan Public Health System’S Response To The 2019 Dengue Insurgence, Luke Bryan

Independent Study Project (ISP) Collection

Dengue virus is in a pandemic status and is a major public health issue in the modern world. The mosquito-borne disease is largely prevalent in Asia and specifically India, where more than half of the states are considered to have complete presence of the dengue virus. The intricate infrastructure of the Indian public health system looks for dengue cases at all levels and reports to the integrated disease surveillance programme (IDSP).

Analyses of the IDSP and trends of dengue cases was done in response to dengue outbreaks throughout the state. Geographic information system (GIS) maps were created to evaluate a ...


Optimizing Water Quality And Temperature Parameters To Increase Survival Rates Of Anotheca Spinosa (Anura: Hylidae) Eggs At The El Valle Amphibian Conservation Center, Morgan Oestereich 2019 SIT Study Abroad

Optimizing Water Quality And Temperature Parameters To Increase Survival Rates Of Anotheca Spinosa (Anura: Hylidae) Eggs At The El Valle Amphibian Conservation Center, Morgan Oestereich

Independent Study Project (ISP) Collection

Amphibians globally are facing extinction due to the fungus Batrachochytrium dendrobatidis (Bd). This has resulted in a worldwide push for increased conservation efforts. These efforts include those of the El Valle Amphibian Conservation Center (EVACC) in El Valle de Antón, Panama, where captive assurance colonies of many native amphibian species are housed. Among these species is Anotheca spinosa, a species of tree frog native to mountainous regions of Central America. This study was performed to analyze the relationship between water quality parameters and egg survival and reproductive success of EVACC’s captive population of A. spinosa and assess how related ...


Metformin Blunts Muscle Hypertrophy In Response To Progressive Resistance Exercise Training In Older Adults: A Randomized, Double‐Blind, Placebo‐Controlled, Multicenter Trial: The Masters Trial, R. Grace Walton, Cory M. Dungan, Douglas E. Long, S. Craig Tuggle, Kate Kosmac, Bailey D. Peck, Heather M. Bush, Alejandro G. Villasante Tezanos, Gerald McGwin, Samuel T. Windham, Fernando Ovalle, Marcas M. Bamman, Philip A. Kern, Charlotte A. Peterson 2019 University of Kentucky

Metformin Blunts Muscle Hypertrophy In Response To Progressive Resistance Exercise Training In Older Adults: A Randomized, Double‐Blind, Placebo‐Controlled, Multicenter Trial: The Masters Trial, R. Grace Walton, Cory M. Dungan, Douglas E. Long, S. Craig Tuggle, Kate Kosmac, Bailey D. Peck, Heather M. Bush, Alejandro G. Villasante Tezanos, Gerald Mcgwin, Samuel T. Windham, Fernando Ovalle, Marcas M. Bamman, Philip A. Kern, Charlotte A. Peterson

Center for Muscle Biology Faculty Publications

Progressive resistance exercise training (PRT) is the most effective known intervention for combating aging skeletal muscle atrophy. However, the hypertrophic response to PRT is variable, and this may be due to muscle inflammation susceptibility. Metformin reduces inflammation, so we hypothesized that metformin would augment the muscle response to PRT in healthy women and men aged 65 and older. In a randomized, double-blind trial, participants received 1,700 mg/day metformin (N = 46) or placebo (N = 48) throughout the study, and all subjects performed 14 weeks of supervised PRT. Although responses to PRT varied, placebo gained more lean body mass (p ...


Probabilistic Modeling Of Democracy, Corruption, Hemophilia A And Prediabetes Data, A. K. M. Raquibul Bashar 2019 University of South Florida

Probabilistic Modeling Of Democracy, Corruption, Hemophilia A And Prediabetes Data, A. K. M. Raquibul Bashar

Graduate Theses and Dissertations

Parametric analysis of any real-world data is the most powerful tool to characterize the probabilistic behavior in social, economic, medical, epidemiological, and other areas of study. In the present study, we identify the theoretical Probability Distribution Function(PDF) for Democracy Index Scores (DIS) from the Economist Intelligence Unit (EIU) database and estimate the maximum likelihood estimates of the theoretical PDFS. We also identify the individual PDFs for each of the clusters, Full Democracy, Flawed Democracy, Hybrid Regime, and Authoritarian Regime defined by the Economist Intelligence Unit (EIU).

A statistical model is a convenient instrument to predict the future value of ...


Estimated Stroke Risk, Yield, And Number Needed To Screen For Atrial Fibrillation Detected Through Single Time Screening: A Multicountry Patient-Level Meta-Analysis Of 141,220 Screened Individuals, Nicole Lowres, David D. McManus, Apurv Soni 2019 University of Sydney

Estimated Stroke Risk, Yield, And Number Needed To Screen For Atrial Fibrillation Detected Through Single Time Screening: A Multicountry Patient-Level Meta-Analysis Of 141,220 Screened Individuals, Nicole Lowres, David D. Mcmanus, Apurv Soni

Open Access Publications by UMMS Authors

BACKGROUND: The precise age distribution and calculated stroke risk of screen-detected atrial fibrillation (AF) is not known. Therefore, it is not possible to determine the number needed to screen (NNS) to identify one treatable new AF case (NNS-Rx) (i.e., Class-1 oral anticoagulation [OAC] treatment recommendation) in each age stratum. If the NNS-Rx is known for each age stratum, precise cost-effectiveness and sensitivity simulations can be performed based on the age distribution of the population/region to be screened. Such calculations are required by national authorities and organisations responsible for health system budgets to determine the best age cutoffs for ...


Neutral Diagnosis: An Innovative Concept For Medical Device Clinical Trials, Bo Zhang, Shangyuan Ye, Sravya B. Shankara, Hui Zhang, Qingfeng Zheng 2019 University of Massachusetts Medical School

Neutral Diagnosis: An Innovative Concept For Medical Device Clinical Trials, Bo Zhang, Shangyuan Ye, Sravya B. Shankara, Hui Zhang, Qingfeng Zheng

Open Access Publications by UMMS Authors

Study design and statistical analysis are crucial in pivotal clinical trials to evaluate the effectiveness and safety of new medical devices under investigation. In recent years, innovative intraoperative in vivo breast tumor diagnostic devices have been proposed to improve the accuracy and surgical outcomes of breast tumor patients undergoing resection. Although such technologies are promising, investigators need to obtain statistical evidence for the effectiveness and safety of these devices by conducting valid clinical trials. However, the study design and statistical analysis for these clinical trials are complicated. While these trials are designed to provide real-time intraoperative diagnosis of cancerous tissue ...


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