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Of Rats And Men, Thomas S. Walsh 2018 Cuny Graduate School of Journalism

Of Rats And Men, Thomas S. Walsh

Capstones

This capstone is a data-driven investigation into New York City's rat problem. By using publicly available government data to map rat activity in NYC, I identified several socio-economic variables that correlate with rat populations at the community district, borough, and city-scale. I used these findings (mainly that rat problems are linked to lower incomes) as the basis of an investigation, which includes interviews with residents, experts, and city officials. Prof. Bobby Corrigan, urban rodentologist and formerly with the NYC Department of Health criticizes the city's efforts for the first time on the record.

https://thomasseiyawalsh.wixsite.com/ratstone


Analysis Of Ranked Gene Tree Probability Distributions Under The Coalescent Process For Detecting Anomaly Zones, Anastasiia Kim 2018 University of New Mexico

Analysis Of Ranked Gene Tree Probability Distributions Under The Coalescent Process For Detecting Anomaly Zones, Anastasiia Kim

Shared Knowledge Conference

In phylogenetic studies, gene trees are used to reconstruct species tree. Under the multispecies coalescent model, gene trees topologies may differ from that of species trees. The incorrect gene tree topology (one that does not match the species tree) that is more probable than the correct one is termed anomalous gene tree (AGT). Species trees that can generate such AGTs are said to be in the anomaly zone (AZ). In this region, the method of choosing the most common gene tree as the estimate of the species tree will be inconsistent and will converge to an incorrect species tree when ...


Genome-Wide Analysis Of Alternative Rna Splicing In Children With Acute Myeloid Leukemia (Aml), Xichen Li 2018 University of New Mexico - Main Campus

Genome-Wide Analysis Of Alternative Rna Splicing In Children With Acute Myeloid Leukemia (Aml), Xichen Li

Shared Knowledge Conference

The pediatric Acute Myeloid Leukemia (AML) is a high-risk and hard-to-treat childhood cancer that originates in the bone marrow from immature white blood cells. Recently, more and more evidence indicates that aberrant splicing of genes is a common characteristic for AML. Gene expression profiles have proved extremely useful for identifying genes that are associated with clinical characteristics and survival outcome of cancer patients. However, conventional gene expression profiles do not account for the differences observed in expressed isoforms when alternative RNA splicing is analyzed. Alternative RNA splicing can generate dozens of distinct transcripts from individual genes and the expressions of ...


Analysis Of Covariance (Ancova) In Randomized Trials: More Precision, Less Conditional Bias, And Valid Confidence Intervals, Without Model Assumptions, Bingkai Wang, Elizabeth Ogburn, Michael Rosenblum 2018 Department of Biostatistics, Johns Hopkins University

Analysis Of Covariance (Ancova) In Randomized Trials: More Precision, Less Conditional Bias, And Valid Confidence Intervals, Without Model Assumptions, Bingkai Wang, Elizabeth Ogburn, Michael Rosenblum

Johns Hopkins University, Dept. of Biostatistics Working Papers

Covariate adjustment" in the randomized trial context refers to an estimator of the average treatment effect that adjusts for chance imbalances between study arms in baseline variables (called “covariates"). The baseline variables could include, e.g., age, sex, disease severity, and biomarkers. According to two surveys of clinical trial reports, there is confusion about the statistical properties of covariate adjustment. We focus on the ANCOVA estimator, which involves fitting a linear model for the outcome given the treatment arm and baseline variables, and trials with equal probability of assignment to treatment and control. We prove the following new (to the ...


Statistical Tools For Assessment Of Spatial Properties Of Mutations Observed Under The Microarray Platform, Bin Luo 2018 The University of Western Ontario

Statistical Tools For Assessment Of Spatial Properties Of Mutations Observed Under The Microarray Platform, Bin Luo

Electronic Thesis and Dissertation Repository

Mutations are alterations of the DNA nucleotide sequence of the genome. Analyses of spatial properties of mutations are critical for understanding certain mutational mechanisms relevant to genetic disease, diversity, and evolution. The studies in this thesis focus on two types of mutations: point mutations, i.e., single nucleotide polymorphism (SNP) genotype differences, and mutations in segments, i.e., copy number variations (CNVs). The microarray platform, such as the Mouse Diversity Genotyping Array (MDGA), detects these mutations genome-wide with lower cost compared to whole genome sequencing, and thus is considered for suitability as a screening tool for large populations. Yet it ...


Cross-Sectional Hiv Incidence Estimation Accounting For Heterogeneity Across Communities, Yuejia Xu, Oliver B. Laeyendecker, Rui Wang 2018 University of Cambridge

Cross-Sectional Hiv Incidence Estimation Accounting For Heterogeneity Across Communities, Yuejia Xu, Oliver B. Laeyendecker, Rui Wang

Harvard University Biostatistics Working Paper Series

No abstract provided.


Basics Of Sample Size And Power Calculations For Comparing Two Groups, Scott C. Quinlan 2018 Himmelfarb Health Sciences Library, The George Washington University

Basics Of Sample Size And Power Calculations For Comparing Two Groups, Scott C. Quinlan

Epidemiology and Biostatistics Faculty Posters and Presentations

No abstract provided.


A Math Research Project Inspired By Twin Motherhood, Tiffany N. Kolba 2018 Valparaiso University

A Math Research Project Inspired By Twin Motherhood, Tiffany N. Kolba

Tiffany N Kolba

The phenomenon of twins, triplets, quadruplets, and other higher order multiples has fascinated humans for centuries and has even captured the attention of mathematicians who have sought to model the probabilities of multiple births. However, there has not been extensive research into the phenomenon of polyovulation, which is one of the biological mechanisms that produces multiple births. In this paper, I describe how my own experience becoming a mother to twins led me on a quest to better understand the scientific processes going on inside my own body and motivated me to conduct research on polyovulation frequencies. An overview of ...


Robust Inference For The Stepped Wedge Design, James P. Hughes, Patrick J. Heagerty, Fan Xia, Yuqi Ren 2018 University of Washington - Seattle Campus

Robust Inference For The Stepped Wedge Design, James P. Hughes, Patrick J. Heagerty, Fan Xia, Yuqi Ren

UW Biostatistics Working Paper Series

Based on a permutation argument, we derive a closed form expression for an estimate of the treatment effect, along with its standard error, in a stepped wedge design. We show that these estimates are robust to misspecification of both the mean and covariance structure of the underlying data-generating mechanism, thereby providing a robust approach to inference for the treatment effect in stepped wedge designs. We use simulations to evaluate the type I error and power of the proposed estimate and to compare the performance of the proposed estimate to the optimal estimate when the correct model specification is known. The ...


Prediction Of Preterm Birth With And Without Preeclampsia Using Mid-Pregnancy Immune And Growth-Related Molecular Factors And Maternal Characteristics, Laura L. Jelliffe-Pawlowski, Larry Rand, Bruce Bedell, Rebecca J. Baer, Scott P. Oltman, Mary E. Norton, Gary M. Shaw, David K. Stevenson, Jeffrey C. Murray, Kelli K. Ryckman 2018 University of Iowa

Prediction Of Preterm Birth With And Without Preeclampsia Using Mid-Pregnancy Immune And Growth-Related Molecular Factors And Maternal Characteristics, Laura L. Jelliffe-Pawlowski, Larry Rand, Bruce Bedell, Rebecca J. Baer, Scott P. Oltman, Mary E. Norton, Gary M. Shaw, David K. Stevenson, Jeffrey C. Murray, Kelli K. Ryckman

Stead Family Department of Pediatrics Publications

OBJECTIVE: To evaluate if mid-pregnancy immune and growth-related molecular factors predict preterm birth (PTB) with and without (±) preeclampsia.

STUDY DESIGN: Included were 400 women with singleton deliveries in California in 2009-2010 (200 PTB and 200 term) divided into training and testing samples at a 2:1 ratio. Sixty-three markers were tested in 15-20 serum samples using multiplex technology. Linear discriminate analysis was used to create a discriminate function. Model performance was assessed using area under the receiver operating characteristic curve (AUC).

RESULTS: Twenty-five serum biomarkers along with maternal age80% of women with PTB ± preeclampsia with best performance in women with ...


Bayesian Analytical Approaches For Metabolomics : A Novel Method For Molecular Structure-Informed Metabolite Interaction Modeling, A Novel Diagnostic Model For Differentiating Myocardial Infarction Type, And Approaches For Compound Identification Given Mass Spectrometry Data., Patrick J. Trainor 2018 University of Louisville

Bayesian Analytical Approaches For Metabolomics : A Novel Method For Molecular Structure-Informed Metabolite Interaction Modeling, A Novel Diagnostic Model For Differentiating Myocardial Infarction Type, And Approaches For Compound Identification Given Mass Spectrometry Data., Patrick J. Trainor

Electronic Theses and Dissertations

Metabolomics, the study of small molecules in biological systems, has enjoyed great success in enabling researchers to examine disease-associated metabolic dysregulation and has been utilized for the discovery biomarkers of disease and phenotypic states. In spite of recent technological advances in the analytical platforms utilized in metabolomics and the proliferation of tools for the analysis of metabolomics data, significant challenges in metabolomics data analyses remain. In this dissertation, we present three of these challenges and Bayesian methodological solutions for each. In the first part we develop a new methodology to serve a basis for making higher order inferences in metabolomics ...


Generalized Spatiotemporal Modeling And Causal Inference For Assessing Treatment Effects For Multiple Groups For Ordinal Outcome., Soutik Ghosal 2018 University of Louisville

Generalized Spatiotemporal Modeling And Causal Inference For Assessing Treatment Effects For Multiple Groups For Ordinal Outcome., Soutik Ghosal

Electronic Theses and Dissertations

This dissertation consists of three projects and can be categorized in two broad research areas: generalized spatiotemporal modeling and causal inference based on observational data. In the first project, I introduce a Bayesian hierarchical mixed effect hurdle model with a nested random effect structure to model the count for primary care providers and understand their spatial and temporal variation. This study further enables us to identify the health professional shortage areas and the possible impacting factors. In the second project, I have unified popular parametric and nonparametric propensity score-based methods to assess the treatment effect of multiple groups for ordinal ...


A Math Research Project Inspired By Twin Motherhood, Tiffany N. Kolba 2018 Valparaiso University

A Math Research Project Inspired By Twin Motherhood, Tiffany N. Kolba

Journal of Humanistic Mathematics

The phenomenon of twins, triplets, quadruplets, and other higher order multiples has fascinated humans for centuries and has even captured the attention of mathematicians who have sought to model the probabilities of multiple births. However, there has not been extensive research into the phenomenon of polyovulation, which is one of the biological mechanisms that produces multiple births. In this paper, I describe how my own experience becoming a mother to twins led me on a quest to better understand the scientific processes going on inside my own body and motivated me to conduct research on polyovulation frequencies. An overview of ...


Investigations Of Biotremors In The Veiled Chameleon (Chamaeleo Calyptratus), Kathryn C. Laslie 2018 Western Kentucky University

Investigations Of Biotremors In The Veiled Chameleon (Chamaeleo Calyptratus), Kathryn C. Laslie

Masters Theses & Specialist Projects

While substrate-borne vibrations are utilized by different reptile species, true conspecific communication via biotremors has not yet been demonstrated in reptiles. This study follows a preliminary report that the veiled chameleon (Chamaeleo calyptratus) could produce biotremors in communicative contexts. I tested chameleon behavioral sensitivity to vibrations by placing them on a dowel attached to a shaker emitting vibrations of 25, 50, 150, 300, and 600 Hz and then measured their changes in velocity before and after the stimulus. I then paired chameleons in various social contexts [anthropogenic disturbance (human disruption of animal); dominance (malemale; female-female C. calyptratus); courtship (male-female C ...


Association Tests For Genetic Effect And Its Interaction With Environmental Factors, Zhengyang Zhou 2018 Southern Methodist University

Association Tests For Genetic Effect And Its Interaction With Environmental Factors, Zhengyang Zhou

Statistical Science Theses and Dissertations

My research is in the area of statistical genetics, and it contains three projects: (1) Differentiating the Cochran-Armitage (CA) trend test and Pearson’s chi-square test: location and dispersion; (2) Decomposing Pearson’s chi-square test: a linear regression and its departure from linearity; (3) Testing nonlinear gene-environment (GxE) interaction through varying coefficient and linear mixed models.

(1) In genetic case-control association studies, a standard practice is to perform the CA trend test with 1 degree-of-freedom (df) under the assumption of an additive model. However, when the true genetic model is recessive or near recessive, it is outperformed by Pearson’s ...


A Qualitative Study Examining The Benefits And Challenges Of Incorporating Patient-Reported Outcome Substance Use And Mental Health Questionnaires Into Clinical Practice To Improve Outcomes On The Hiv Care Continuum., Anne K Monroe, Sarah M Jabour, Sebastian Peña, Jeanne C Keruly, Richard D Moore, Geetanjali Chander, Kristin A Riekert 2018 George Washington University

A Qualitative Study Examining The Benefits And Challenges Of Incorporating Patient-Reported Outcome Substance Use And Mental Health Questionnaires Into Clinical Practice To Improve Outcomes On The Hiv Care Continuum., Anne K Monroe, Sarah M Jabour, Sebastian Peña, Jeanne C Keruly, Richard D Moore, Geetanjali Chander, Kristin A Riekert

Epidemiology and Biostatistics Faculty Publications

BACKGROUND: Inadequate identification and treatment of substance use (SU) and mental health (MH) disorders hinders retention in HIV care. The objective of this study was to elicit stakeholder input on integration of SU/MH screening using computer-assisted patient-reported outcomes (PROs) into clinical practice.

METHODS: We conducted semi-structured interviews with HIV-positive patients who self-reported SU/MH symptoms on a computer-assisted PROs (n = 19) and HIV primary care providers (n = 11) recruited from an urban academic HIV clinic. Interviews were audio-recorded and transcribed. We iteratively developed codes and organized key themes using editing style analysis.

RESULTS: Two themes emerged: (1) Honest Disclosure ...


Quantitative Electroencephalography For Detecting Concussions, Sara Krehbiel, Kathy Hoke, Joanna Wares 2018 University of Richmond

Quantitative Electroencephalography For Detecting Concussions, Sara Krehbiel, Kathy Hoke, Joanna Wares

Biology and Medicine Through Mathematics Conference

No abstract provided.


Prevention Paradox: Medical Students Are Less Inclined To Prescribe Hiv Pre-Exposure Prophylaxis For Patients In Highest Need., Sarah K Calabrese, Valerie A Earnshaw, Kristen Underhill, Douglas S Krakower, Manya Magnus, Nathan B Hansen, Kenneth H Mayer, Joseph R Betancourt, Trace S Kershaw, John F Dovidio 2018 George Washington University

Prevention Paradox: Medical Students Are Less Inclined To Prescribe Hiv Pre-Exposure Prophylaxis For Patients In Highest Need., Sarah K Calabrese, Valerie A Earnshaw, Kristen Underhill, Douglas S Krakower, Manya Magnus, Nathan B Hansen, Kenneth H Mayer, Joseph R Betancourt, Trace S Kershaw, John F Dovidio

Epidemiology and Biostatistics Faculty Publications

INTRODUCTION: Despite healthcare providers' growing awareness of pre-exposure prophylaxis (PrEP), prescription rates remain low. PrEP is an efficacious HIV prevention strategy recommended for use with condoms but still protective in their absence. Concern about the impact of PrEP on condom use and other risk behaviour is, nonetheless, among the barriers to prescription commonly reported. To understand the implications of this concern for PrEP access, we examined how medical students' willingness to prescribe PrEP varied by patients' condom use and partnering practices. We also assessed the perceived acceptability of various reasons for condom discontinuation with PrEP.

METHODS: An online survey was ...


Spatio-Temporal Dynamics Of Atlantic Cod Bycatch In The Maine Lobster Fishery And Its Impacts On Stock Assessment, Robert E. Boenish 2018 University of Maine

Spatio-Temporal Dynamics Of Atlantic Cod Bycatch In The Maine Lobster Fishery And Its Impacts On Stock Assessment, Robert E. Boenish

Electronic Theses and Dissertations

Of the most iconic fish species in the world, the Atlantic cod (Gadus morhua, hereafter, cod) has been a mainstay in the North Atlantic for centuries. While many global fish stocks have received increased pressure with the advent of new, more efficient fishing technology in the mid-20th century, exceptional pressure has been placed on this prized gadoid. Bycatch, or the unintended catch of organisms, is one of the biggest global fisheries issues. Directly resulting from the failed recovery of cod in the GoM, attention has been placed as to possible sources of unaccounted catch. Among the most prominent is ...


The Ethics In Synthetics: Statistics In The Service Of Ethics And Law In Health-Related Research In Big Data From Multiple Sources, Sharon Bassan Ph.D., Ofer Harel Ph.D. 2018 Princeton University

The Ethics In Synthetics: Statistics In The Service Of Ethics And Law In Health-Related Research In Big Data From Multiple Sources, Sharon Bassan Ph.D., Ofer Harel Ph.D.

Journal of Law and Health

An ethical advancement of scientific knowledge demands a delicate equilibrium between benefits and harms, in particular in health-related research. When applying and advancing scientific knowledge or technologies, Article 4 of UNESCO’s Universal Declaration on Bioethics and Human Rights, ethically justifiable research requires maximizing direct and indirect benefits and minimizing possible harms. The National Institution of Health [NIH] Data Sharing Policy and Implementation Guidance similarly states that data necessary for drawing valid conclusions and advancing medical research should be made as widely and freely available as possible (in order to share the benefits) while safeguarding the privacy of participants from ...


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