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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


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.


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 ...


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 ...


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 ...


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 ...


Oxidative Stress And Cardiovascular Risk In Type 1 Diabetes Mellitus: Insights From The Dcct/Edic Study, W. Wilson Tang, P. McGee, John M. Lachin, D. Li, B. Hoogwerf, S. Hazen, +several additional authors 2018 George Washington University

Oxidative Stress And Cardiovascular Risk In Type 1 Diabetes Mellitus: Insights From The Dcct/Edic Study, W. Wilson Tang, P. Mcgee, John M. Lachin, D. Li, B. Hoogwerf, S. Hazen, +Several Additional Authors

Epidemiology and Biostatistics Faculty Publications

Background--Hyperglycemia leading to increased oxidative stress is implicated in the increased risk for the development of macrovascular and microvascular complications in patients with type 1 diabetes mellitus. Methods and Results--A random subcohort of 349 participants was selected from the DCCT/EDIC (Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications) cohort. This included 320 controls and 29 cardiovascular disease cases that were augmented with 98 additional known cases to yield a case cohort of 447 participants (320 controls, 127 cases). Biosamples from DCCT baseline, year 1, and closeout of DCCT, and 1 to 2 years post-DCCT (EDIC years ...


Response To Persistent Er Stress In Plants: A Multiphasic Process That Transitions Cells From Prosurvival Activities To Cell Death, Renu Srivastava, Zhaoxia Li, Giulia Russo, Jie Tang, Ran Bi, Usha Muppirala, Sivanandan Chudalayandi, Andrew J. Severin, Mingze He, Samuel I. Vaitkevicius, Carolyn J. Lawrence-Dill, Peng Liu, Ann E. Stapleton, Diane C. Bassham, Federica Brandizzi, Stephen H. Howell 2018 Iowa State University

Response To Persistent Er Stress In Plants: A Multiphasic Process That Transitions Cells From Prosurvival Activities To Cell Death, Renu Srivastava, Zhaoxia Li, Giulia Russo, Jie Tang, Ran Bi, Usha Muppirala, Sivanandan Chudalayandi, Andrew J. Severin, Mingze He, Samuel I. Vaitkevicius, Carolyn J. Lawrence-Dill, Peng Liu, Ann E. Stapleton, Diane C. Bassham, Federica Brandizzi, Stephen H. Howell

Office of Biotechnology Publications

The unfolded protein response (UPR) is a highly conserved response that protects plants from adverse environmental conditions. The UPR is elicited by endoplasmic reticulum (ER) stress, in which unfolded and misfolded proteins accumulate within the ER. Here, we induced the UPR in maize (Zea mays) seedlings to characterize the molecular events that occur over time during persistent ER stress. We found that a multiphasic program of gene expression was interwoven among other cellular events, including the induction of autophagy. One of the earliest phases involved the degradation by regulated IRE1-dependent RNA degradation (RIDD) of RNA transcripts derived from a family ...


Probabilistic Pairwise Model Comparisons Based On Discrepancy Measures And A Reconceptualization Of The P-Value, Benjamin N. Riedle 2018 University of Iowa

Probabilistic Pairwise Model Comparisons Based On Discrepancy Measures And A Reconceptualization Of The P-Value, Benjamin N. Riedle

Theses and Dissertations

Discrepancy measures are often employed in problems involving the selection and assessment of statistical models. A discrepancy gauges the separation between a fitted candidate model and the underlying generating model. In this work, we consider pairwise comparisons of fitted models based on a probabilistic evaluation of the ordering of the constituent discrepancies. An estimator of the probability is derived using the bootstrap.

In the framework of hypothesis testing, nested models are often compared on the basis of the p-value. Specifically, the simpler null model is favored unless the p-value is sufficiently small, in which case the null model is rejected ...


Aggressive Diuresis And Severity-Adjusted Length Of Hospital Stay In Acute Congestive Heart Failure Patients., Muhammad U. Butt M.D. 2018 Selected Works

Aggressive Diuresis And Severity-Adjusted Length Of Hospital Stay In Acute Congestive Heart Failure Patients., Muhammad U. Butt M.D.

Muhammad Umer Butt M.D., MSCRD

To see if aggressive diuresis in 1st 24 hours is associated with a comparable number of total days in the hospital as compared to non-aggressive diuresis.  In this retrospective cohort study, we compared the length of hospital stay of consecutive patients admitted in one year based on their diuresis during the first twenty-four hours of hospitalization: aggressive diuresis (group 1) i.e. >2400mL versus non-aggressive diuresis (group 2) i.e. ≤ 2400mL urine output. Patients were excluded if in cardiogenic shock, had creatinine level above 3 mg/dL on admission, or on dialysis. A total of 194 patients were enrolled (29 ...


Analysis Challenges For High Dimensional Data, Bangxin Zhao 2018 The University of Western Ontario

Analysis Challenges For High Dimensional Data, Bangxin Zhao

Electronic Thesis and Dissertation Repository

In this thesis, we propose new methodologies targeting the areas of high-dimensional variable screening, influence measure and post-selection inference. We propose a new estimator for the correlation between the response and high-dimensional predictor variables, and based on the estimator we develop a new screening technique termed Dynamic Tilted Current Correlation Screening (DTCCS) for high dimensional variables screening. DTCCS is capable of picking up the relevant predictor variables within a finite number of steps. The DTCCS method takes the popular used sure independent screening (SIS) method and the high-dimensional ordinary least squares projection (HOLP) approach as its special cases.

Two methods ...


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