Engineering Commons^™

Augmentative And Alternative Communication Use, Service Delivery Experiences, And Communicative Participation For People With Amyotrophic Lateral Sclerosis, Betts Peters

Dissertations and Theses

People with amyotrophic lateral sclerosis (ALS) often experience changes to their speech, and may use augmentative and alternative communication (AAC) devices and techniques to maintain the ability to communicate. The use of AAC may facilitate the participation of people with ALS in various life situations involving communication. There is limited data in the literature about the AAC approaches currently used by people with ALS, the professional services they receive to support communication, or the effects of AAC on their communicative participation. This dissertation involved a nationwide online survey of people with ALS, and comprises three papers intended to add to …

Reconstructability Analysis: Discrete Multivariate Modeling, Martin Zwick

Systems Science Faculty Publications and Presentations

An introduction to Reconstructability Analysis for the Discrete Multivariate Modeling course and for other purposes.

Modeling Renal Function During Pregnancy, Christina A. Valtierra

REU Final Reports

The main goal of this research project is to build a computational model that illustrates the main processes in renal function during pregnancy. The analysis of how pregnancy affects all the factors that take place within the kidney will allow for a better understanding of how pathologies like proteinuria, hypertension, and glomerular endotheliosis develop. This model is a small part of a more complex model that showcases the complete pathophysiology of preeclampsia.

Ronald E. Mcnair Scholars Program Profiles And Abstracts 2021, Mcnair Scholars Program

McNair Symposium

This is the complete event program and provides presentation abstracts and biographies of McNair scholars and their mentors.

Graphical Models In Reconstructability Analysis And Bayesian Networks, Marcus Harris, Martin Zwick

Systems Science Faculty Publications and Presentations

Reconstructability Analysis (RA) and Bayesian Networks (BN) are both probabilistic graphical modeling methodologies used in machine learning and artificial intelligence. There are RA models that are statistically equivalent to BN models and there are also models unique to RA and models unique to BN. The primary goal of this paper is to unify these two methodologies via a lattice of structures that offers an expanded set of models to represent complex systems more accurately or more simply. The conceptualization of this lattice also offers a framework for additional innovations beyond what is presented here. Specifically, this paper integrates RA and …

Effect Of Bout Length On Gait Measures In People With And Without Parkinson’S Disease During Daily Life, Vrutangkumar Shah, James Mcnames, Graham Harker, Martina Mancini, Patricia Carlson-Kuhta, John G. Nutt, Mahmoud El-Gohary, Carolin Curtze, Fay Horak

Electrical and Computer Engineering Faculty Publications and Presentations

Although the use of wearable technology to characterize gait disorders in daily life is increasing, there is no consensus on which specific gait bout length should be used to characterize gait. Clinical trialists using daily life gait quality as study outcomes need to understand how gait bout length affects the sensitivity and specificity of measures to discriminate pathological gait as well as the reliability of gait measures across gait bout lengths. We investigated whether Parkinson’s disease (PD) affects how gait characteristics change as bout length changes, and how gait bout length affects the reliability and discriminative ability of gait measures …

Ronald E. Mcnair Scholars Program Profiles And Abstracts 2020, Mcnair Scholars Program

McNair Symposium

This is the complete event program and provides presentation abstracts and biographies of McNair scholars and their mentors.

Managing Healthcare Data Assets As A Complex Adaptive System, Katie Clifton

Systems Science Friday Noon Seminar Series

A major project is underway to develop a shared platform for data and analytics in a highly federated healthcare delivery organization. In the status quo data environment, analysts have integrated information from various domains — medical records, claims, membership — to produce a multitude of reports and analysis. Duplicative, mis-aligned, and siloed datasets were created as an unintended consequence.

One objective of the project is to produce outcomes (reports, analysis) that are more standardized and efficient than the status quo without sacrificing adaptability. Standards and practices are being intentionally developed as a mechanism for this emerging system to achieve more …

Benzene Formation In Electronic Cigarettes, James F. Pankow, Kilsun Kim, Kevin J. Mcwhirter, Wentai Luo, Jorge O. Escobedo, Robert M. Strongin, Anna K. Duell, David H. Peyton

Chemistry Faculty Publications and Presentations

The heating of the fluids used in electronic cigarettes (“e-cigarettes”) used to create “vaping” aerosols is capable of causing a wide range of degradation reaction products. We investigated formation of benzene (an important human carcinogen) from e-cigarette fluids containing propylene glycol (PG), glycerol (GL), benzoic acid, the flavor chemical benzaldehyde, and nicotine.

Selecting Medical Hardware Using Pairwise Comparisons: A Patient's Perspective Of Cochlear Implant Device Selection, Timothy R. Anderson, Shabnam Razeghian Jahromi

Engineering and Technology Management Faculty Publications and Presentations

Selecting medical hardware can be a difficult and permanent decision for patients that they are often unprepared for. The authors explore the use of pairwise comparison techniques to better inform medical decision making in an application of choosing between three major cochlear implant manufacturers. This paper appears to be the first study to apply a pairwise comparison decision making approach for cochlear implant device selection. Also, unlike many medical decision making studies that are developed by the healthcare professional, this model and analysis was conducted entirely by the patient for the purpose of making the real-world decision of a device. …

Study Design Of A Cluster-Randomized Controlled Trial To Evaluate A Large-Scale Distribution Of Cook Stoves And Water Filters In Western Province, Rwanda, Corey L. Nagel, Miles Kirby, Laura D. Zambrano, Ghislaine Rosa, Christina K. Barstow, Evan A. Thomas, Thomas Clasen

Mechanical and Materials Engineering Faculty Publications and Presentations

Background: In Rwanda, pneumonia and diarrhea are the first and second leading causes of death, respectively, among children under five. Household air pollution (HAP) resultant from cooking indoors with biomass fuels on traditional stoves is a significant risk factor for pneumonia, while consumption of contaminated drinking water is a primary cause of diarrheal disease. To date, there have been no largescale effectiveness trials of programmatic efforts to provide either improved cookstoves or household water filters at scale in a low-income country. In this paper we describe the design of a clusterrandomized trial to evaluate the impact of a national-level program …

Process Evaluation And Assessment Of Use Of A Large Scale Water Filter And Cookstove Program In Rwanda, Christina K. Barstow, Corey Nagel, Thomas Clasen, Evan A. Thomas

OHSU-PSU School of Public Health Faculty Publications and Presentations

Background: In an effort to reduce the disease burden in rural Rwanda, decrease poverty associated with expenditures for fuel, and minimize the environmental impact on forests and greenhouse gases from inefficient combustion of biomass, the Rwanda Ministry of Health (MOH) partnered with DelAgua Health (DelAgua), a private social enterprise, to distribute and promote the use of improved cookstoves and advanced water filters to the poorest quarter of households (Ubudehe 1 and 2) nationally, beginning in Western Province under a program branded Tubeho Neza (“Live Well”). The project is privately financed and earns revenue from carbon credits under the United Nations …

Acid-Base Equilibria In Organic-Solvent/Water Mixtures And Their Relevance To Gas/Particle Partitioning In The Atmosphere And In Tobacco Smoke, Julia Lynn Degagne

Dissertations and Theses

Acid-base equilibria in organic particulate matter (PM) are poorly understood, but have important implications for air quality and public health. First, acid-base reactions in organic particulate matter affect the gas/particle partitioning of organic compounds in the atmosphere, and these processes are not currently represented in atmospheric and climate change models. Second, the acid-base balance of tobacco smoke affects the amount of nicotine absorbed by the smoker, and a greater understanding of this balance would help to relate cigarette smoke composition to the addictive properties of cigarettes. This work presents data related to both air quality and tobacco smoke modeling.

The …

Flavour Chemicals In Electronic Cigarette Fluids, Peyton A. Tierney, Clarissa D. Karpinski, Jessica E. Brown, Wentai Luo, James F. Pankow

Chemistry Faculty Publications and Presentations

Background: Most e-cigarette liquids contain flavour chemicals. Flavour chemicals certified as safe for ingestion by the Flavor Extracts Manufacturers Association may not be safe for use in e-cigarettes. This study identified and measured flavour chemicals in 30 e-cigarette fluids.

Methods: Two brands of single-use e-cigarettes were selected and their fluids in multiple flavour types analysed by gas chromatography/mass spectrometry. For the same flavour types, and for selected confectionary flavours (eg, bubble gum and cotton candy), also analysed were convenience samples of e-cigarette fluids in refill bottles from local ‘vape’ shops and online retailers.

Results: In many liquids, total flavour chemicals …

Assessment Of Similarity In Chemically Complex Samples, Jessica Elise Brown

Dissertations and Theses

Concern within the public health community is mounting regarding what some deem as "candy-flavored tobacco". A recent study by King et al. (2014) found that >40% of middle and high school student smokers use flavored cigarettes or flavored little cigars. This study investigated the validity of the "candy-flavored tobacco" designation by comparing flavor profiles of 18 flavored tobacco products with 15 candy and Kool-Aid products using gas chromatography mass spectrometry (GC/MS). Significant compositional overlap was found; nearly 75% of the compounds detected were present in at least one flavored tobacco and one candy or Kool-Aid product. Benzaldehyde and or benzyl …

Assessing The Impact Of Water Filters And Improved Cook Stoves On Drinking Water Quality And Household Air Pollution: A Randomised Controlled Trial In Rwanda, Ghislaine Rosa, Fiona Majorin, Sophie Boisson, Christina Barstow, Michael Johnson, Miles Kirby, Fidele Ngabo, Evan A. Thomas, Thomas Clasen

Mechanical and Materials Engineering Faculty Publications and Presentations

Diarrhea and respiratory infections remain the biggest killers of children under 5 years in developing countries. We conducted a 5-month household randomised controlled trial among 566 households in rural Rwanda to assess uptake, compliance and impact on environmental exposures of a combined intervention delivering high-performance water filters and improved stoves for free. Compliance was measured monthly by self-report and spot-check observations. Semicontinuous 24-h PM2.5 monitoring of the cooking area was conducted in a random subsample of 121 households to assess household air pollution, while samples of drinking water from all households were collected monthly to assess the levels of thermotolerant …

Efferent Copy And Corollary Discharge Motor Control Behavior Associated With A Hopping Activity, Wangdo Kim, António P. Veloso, Filipa João, Sean S. Kohles

Mechanical and Materials Engineering Faculty Publications and Presentations

Hoppers respond not only to stimuli from the ground surfaces but also to cues generated by their own behaviors. This leads to desensitization because although the afferent and reafferent signals have distinct causes, they are carried by the same sensory channels. From a behavioral viewpoint, it may be necessary to distinguish between signals from the two causes especially when monitoring changes in the external environment separate from those due to self-movement. We were able to separate afferent sensory stimuli from self-generated, reafferent signals using an action oriented perception system and dynamic programming approach. This effort addressed the question of how …

Automated Channel Assessment For Single Chip Medradio Transceivers, Mark Alexander Hillig

Dissertations and Theses

Modern implantable and body worn medical devices leverage wireless telemetry to improve patient experience and expand therapeutic options. Wireless medical devices are subject to a unique set of regulations in which monitoring of the available frequency spectrum is a requirement. To this end, implants use software protocols to assess the in-band activity to determine which channel should be used. These software protocols take valuable processing time and possibly degrade the operational lifetime of the battery. Implantable medical devices often take advantage of a single chip transceiver as the physical layer for wireless communications. Embedding the channel assessment task in the …

Tracking Knee Joint Functional Axes Through Tikhonov Filtering And Plűcker Coordinates, Wangdo Kim, Yoon-Hyuk Kim, António P. Veloso, Sean S. Kohles

Mechanical and Materials Engineering Faculty Publications and Presentations

Researchers have reported several compensation methods to estimate bone and joint position from a cluster of skin-mounted markers as influenced by Soft Tissue Artifacts (STA). Tikhonov Regularization Filtering (TRF) as a means to estimate Instantaneous Screw Axes (ISA) was introduced here as a means to reduce the displacement of a rigid body to its simplest geometric form. Recent studies have suggested that the ISA of the knee, i.e., Knee Functional Axes (KFA), might be closely connected to the estimation of constraint forces such as those due to medial and lateral connective tissues. The estimations of ISAs were known to be …

Thirdhand Tobacco Smoke: Emerging Evidence And Arguments For A Multidisciplinary Research Agenda, Georg E. Matt, Penelope J. Quintana, Hugo Destaillats, Lara A. Gundel, Mohamad Sleiman, Brett C. Singer, Peyton Jacob, Jonathan P. Winickoff, Prue Talbot, Suzaynn Schick, Yinsheng Wang, Bo Hang, Manuela Martins-Green, James F. Pankow, Melbourne F. Hovell, Neal L. Benowitz, Virender K. Rehan, Jonathan M. Samet

Civil and Environmental Engineering Faculty Publications and Presentations

There is broad consensus regarding the health impact of tobacco use and secondhand smoke exposure, yet considerable ambiguity exists about the nature and consequences of thirdhand smoke (THS). We introduce definitions of THS and THS exposure and review recent findings about constituents, indoor sorption-desorption dynamics, and transformations of THS; distribution and persistence of THS in residential settings; implications for pathways of exposure; potential clinical significance and health effects; and behavioral and policy issues that affect and are affected by THS. Physical and chemical transformations of tobacco smoke pollutants take place over time scales ranging from seconds to months and include …

A System Dynamics Model Of Pharmaceutical Opioids: Medical Use, Diversion, And Nonmedical Use, Teresa D. Schmidt, Wayne W. Wakeland, J. David Haddox

Wayne W. Wakeland

Abstract: A dramatic rise in the nonmedical of pharmaceutical opioids has presented the United States with a substantial public health problem. Nonmedical use of prescription pain relievers has become increasingly prevalent in the US over the last two decades, and diversion of medicines obtained by prescription is assumed to be a major source of supply for nonmedical opioid use. Policymakers striving to protect population health by ameliorating the adverse outcomes of nonmedical use of opioid analgesics could benefit from a systems-level model which reflects the complexity of the system and incorporates the full range of available data. To address this …

A System Dynamics Model Of Pharmaceutical Opioids: Medical Use, Diversion, And Nonmedical Use, Teresa Schmidt, Wayne Wakeland, J. David Haddox

Systems Science Faculty Publications and Presentations

A dramatic rise in the nonmedical of pharmaceutical opioids has presented the United States with a substantial public health problem. Nonmedical use of prescription pain relievers has become increasingly prevalent in the US over the last two decades, and diversion of medicines obtained by prescription is assumed to be a major source of supply for nonmedical opioid use. Policymakers striving to protect population health by ameliorating the adverse outcomes of nonmedical use of opioid analgesics could benefit from a systems-level model which reflects the complexity of the system and incorporates the full range of available data. To address this need, …

Reproducing Published Results From In Silico Computer Models Of The Acute Inflammatory Response To Severe Sepsis, Wayne W. Wakeland, Joe Fusion, Brahm Goldstein

Systems Science Faculty Publications and Presentations

Recent studies describe computer simulation models of the acute or systemic inflammatory response (AIR or SIR) to severe sepsis, a condition that can lead to multiple organ failure and death. One study used an agent-based model, while the other used differential equations (DEs) to simulate a randomized clinical trial. Both studies obtained results similar to the actual results from a successful clinical drug trial of severe sepsis, suggesting that in silico (simulated) randomized clinical trials may be used to design more effective in vivo clinical trials.

Dynamic Matrix Composition In Engineered Cartilage With Stochastic Supplementation Of Growth Factors, Asit K. Saha, J. (Jagannath) Mazumdar, Sean S. Kohles

Mechanical and Materials Engineering Faculty Publications and Presentations

Dynamic extracellular matrix (ECM) synthesis is explored in a hypothesized engineered cartilage construct. Growth (α) and decay (β) rate parameters are developed from a previous engineered cartilage model. The presented mathematical model was constructed from the parameterized experimental data using a deterministic and stochastic examination of ECM synthesis based on a negative feedback control mechanism. A growth factor supplementation is incorporated in a probabilistic mathematical approach. The growth factor component modified an initial deterministic model through a Gaussian white noise fluctuation. As the primary constituents of ECM, the mathematical tool is intended to characterize the probable steady state distribution of …

Investigation Of Blood Pressure Measurement Using A Hydraulic Occlusive Cuff, Kusha R. Bhattarai

Dissertations and Theses

This thesis presents an improved oscillotonometric system for the measurement of human blood pressure. The study included:

1. The design of a hydraulic occlusive cuff,

2. The investigation of the wave forms taken from the blood pressure measurements, and

3. The design of a mechanism for the simulation of human blood pressure pulse.

In this study, an experimental system consisting of a rigid shell occlusive cuff, a constant volume displacement pump, a transducer, and a chart recorder was designed and used for data collection.