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Hospital Location, Socioeconomic Factors, And Obesity Impact On Patient Readmission Rates 30 Days Post-Coronary Artery Bypass Graft, Mazalo Looky

Walden Dissertations and Doctoral Studies

Coronary artery bypass graft (CABG) is associated with a high rate of readmissions within 30 days after discharge. Patient variables such as obesity and socioeconomic status (SES) are modifiable, whereas hospital factors such as location indicate the need for a better regional needs assessment. The purpose of this study was to examine the impact of hospital location, SES, and obesity (independent variables) on the 30-day readmission rate post-CABG (dependent variable) among US patients. Secondary data sets available from the Centers for Medicare & Medicaid Services and the Society of Thoracic Surgery websites were analyzed to assess the impact of location, …

Enhancement Of Ambient Air Quality Index Forecasting Using Optimized Ensemble Model, Vanitha M

Theses and Dissertations

Forecasting ambient air quality is essential for environmental sustainability and public health, especially in heavily populated regions such as China, India, and the United States where air pollution remains a serious concern. Traditional forecasting models often struggle to accurately represent air quality data because of its complex patterns and nonlinear interactions. To address these challenges and improve forecast performance, this research proposes a comprehensive strategy that integrates parallel heterogeneous ensemble modeling with Bayesian optimization.

The study begins with a seasonal machine learning–based imputation technique (SeasonalMLImpute) designed to handle missing data in meteorological and air quality parameters. This method is evaluated …

Exploring The Factors Involved To Support African American Males' Success In Mathematics During The Early Grades, Elmore Travis Collier

LMU Theses and Dissertations

This study used a mixed methods approach to examine the instructional and social emotional factors that support African American boys’ success during early elementary grades. The study investigated key influences including teacher and parent demographics, student-teacher, and parent-student relationships, building mathematical confidence in students, and approaching math as a long-term investment. It explored how these factors existed within an ecosystem that contributed to positive math outcomes for students by the third grade. The study used surveys and interviews of teachers, parents, and students to describe instructional activities, relationships, and interactions at school and home that supported positive math outcomes. Findings …

Microstructured Microstructure: Effects Of Concentration Variations On Shock Initiation Of Hmx-Based Plastic Explosives, Dana D. Dlott, Lawrence Salvati, Siva Kumar Valluri

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We studied shock-compressed plastic-bonded explosives (PBX) consisting of HMX (cyclotetramethylene-tetranitramine) with PDMS (poly-dimethylsiloxane) binder, where we varied the HMX weight percent (wt%) up to a maximum of 60 wt%. In this lower-concentration regime, HMX particle clustering causes the PBX structure to consist of HMX clusters and PDMS islands. Structural analysis by optical microscopy allowed us to compute a radial correlation function that gives the mean distance from an average HMX particle to the nearest polymer island. Short-duration 20 GPa shocks (4 ns) created hot spots, and time-resolved thermal emission was used to obtain the growth rate of the subsequent deflagration. …

Accelerating Shock-Driven Reactions In Metal Nanocomposites, Siva Kumar Valluri, Edward L. Dreizin, Dana D. Dlott

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Metal powders are sought as energetic additives to conventional explosives. However, due to their sluggish reaction kinetics with external gaseous oxidizers, pure metals are replaced with metallic composites with intimately mixed condensed phase oxidizers prepared by arrested reactive milling (ARM). Such composites can be initiated by non-thermal, mechanical means; through shear mixing of fuel and oxidizer under a shock compressive load. Since the ARM preparatory technique allows for tuning multiple powder attributes such as fuel/oxidizer of interest, their degree of mixing, amount of oxidizer, particle porosity, among others, a parametric study is crucial in identifying suitable traits for fast reactions …

12.09.2024 Orsp Connect, Liz Williamson

ORED Newsletter

Employee Profiles

In Person Account Reconciliation and Tableau Training

NSF Proposals with Consultant or Professional Services

Ud In The News Nov. 30-Dec. 6, University Of Dayton

News Releases

National media highlighted UD engineering research and Charles Russo's legal expertise. Local media featured an engineering student's work with United Rehabilitation Services to help a local teen learn to handle everyday tasks.

Adipocyte-Derived Small Extracellular Vesicles Exacerbate Diabetic Ischemic Heart Injury By Promoting Oxidative Stress And Mitochondrial-Mediated Cardiomyocyte Apoptosis, Lu Gan, Jianli Zhao, Peng Yao, Theodore A. Christopher, Bernard Lopez, Wayne B. Lau, Walter Koch, Erhe Gao, Xin-Liang Ma, Yajing Wang

Department of Emergency Medicine Faculty Papers

BACKGROUND: Diabetes increases ischemic heart injury via incompletely understood mechanisms. We recently reported that diabetic adipocytes-derived small extracellular vesicles (sEV) exacerbate myocardial reperfusion (MI/R) injury by promoting cardiomyocyte apoptosis. Combining in vitro mechanistic investigation and in vivo proof-concept demonstration, we determined the underlying molecular mechanism responsible for diabetic sEV-induced cardiomyocyte apoptosis after MI/R.

METHODS AND RESULTS: Adult mice were fed a high-fat diet (HFD) for 12 weeks. sEV were isolated from plasma or epididymal adipose tissue. HFD significantly increased the number and size of plasma- and adipocyte-derived sEV. Intramyocardial injection of an equal number of diabetic plasma sEV in nondiabetic …

Sd-Weat: Towards Robustly Measuring Bias In Input Embeddings For Artificial Intelligence Language Models, Magnus Gray

Theses and Dissertations

Artificial intelligence (AI) is rapidly transforming industries and markets, from healthcare to entertainment, revolutionizing decision-making processes. However, as AI grow more influential, they also risk amplifying existing biases, potentially leading to harmful consequences. Recent advancements in large language models (LLMs), such as GPT-4 and Llama, have heightened concerns about bias in natural language processing (NLP) tasks, driving the need for robust methods to detect and mitigate bias. Current approaches, such as the Word Embedding Association Test (WEAT) and its sentence-level extension the Sentence Encoder Association Test (SEAT) often fall short in capturing the nuances of biases in the input embeddings …

When Help Hurts: Workplace Instrumental Support And Employee Emotional Exhaustion Within-Person, Jensine Paoletti-Hatcher, Anthony T. Misisco, Eden B. King

Psychology Faculty Publications and Presentations

The social support paradox describes mixed findings on the effects of social support on well-being. An application of the person-environment fit perspective can address the paradox by reasoning that similar quantities of social support needs and social support supplies should result in optimal well-being outcomes. We integrate a person-environment fit perspective with self-determination theory in an examination of the relationship between workplace instrumental support and emotional exhaustion through a two-week experience sampling method study. Fifty-nine participants responded to questions about desired quantities of work-related help from their colleagues (coworkers and supervisors) and their perceived quantities of work-related help after work …

Algorithmic Reconstruction Of High-Fidelity Synthetic Sird Data, Dylan Mack

Electrical and Systems Engineering Undergraduate Student Research

During infectious disease outbreaks, epidemiologists are faced with problems similar to those of state estimation. Often, only population-level measures of the outbreak are available, such as infection counts per week or test positivity rates. However, these aggregate statistics yield little insight into the individual-level dynamics of an epidemic. Further, empirical data does not directly measure transmission network structure and producing this information via contact tracing is extremely resource-intensive and scales poorly. In this poster, I present an algorithm that produces synthetic, individual-level disease state measurements that both obey the mechanics of an SIRD model and, in aggregate, match empirical infection …

Mems 411: Electrostatic Precipitator Design For Washu Racing Composites Team, Robert J. Wild, Takato Muro, Jackson Ford, David Wiggin

Mechanical Engineering Design Project Class

The objective of this paper is to develop an effective method to remove carbon fiber particulates from the air in the WashU Racing garage using electrostatic precipitation.

Mems 411: Talking Goniometer, Jeffrey Reinhold, Matthew Ren, Corin Riahi, Moises Rodriguez

Mechanical Engineering Design Project Class

Our project is about designing a goniometer that will aid Rachel Apter, an occupational therapy graduate student, more easily determine the angles created by limbs bending about a joint. A goniometer is essentially a protractor designed to affix its base arm to a stationary limb and it’s rotating arm to a moving limb. The moving arm follows the moving limb, measuring the coupled limb’s range of motion. The main complaint centering around goniometers is that they are hard to read due to the small tick marks that indicate the angle. To fix this problem, the goniometer will be edited to …

Mems 411: The Ball Bearing Sorter Group N, Jack Zhao, Anri Cifuentes, Shawn Xiong, Richard Li

Mechanical Engineering Design Project Class

The challenge was to design and develop an automated device capable of sorting and packaging six types of ball bearings—varying in size (1/4 inch and 1/2 inch) and material (stainless steel, brass, and nylon). The device needed to meet strict performance and design constraints, including fitting within a compact 20x20x20-inch footprint, weighing no more than 15 pounds, and sorting bearings with high speed and accuracy.

This problem represents a practical scenario in automated manufacturing, where efficient and precise sorting is crucial for streamlining assembly line operations. The solution required integrating innovative engineering mechanisms, such as size differentiation, material separation, and …

Mems 411: Mailbox Assistant, Peter Scholl, Benjamin Cortes, Garbiel Arcas, Colin Zeiss

Mechanical Engineering Design Project Class

Oftentimes elderly people struggle with reaching into their curbside mailbox from their car, especially if the mail is pushed all the way to the back. With the Mailbox Assistant, sore shoulders can be saved through a drawer that slides out from the mailbox. This modification can be made to any mailbox without altering the outside appearance thus keeping it within HOA standards.

Mems 411: Hydroponic Gardening System, Tiger Lu, Aj Shanahan, Jaquelin Guzman, Brandon Lacy

Mechanical Engineering Design Project Class

This report summarizes the engineering design process undertaken for the development of a hydroponic gardening system. The project began with selecting a concept, as a team, we decided to focus on designing a system tailored to community gardening needs. The report is organized into five main sections: Problem Understanding, Concept Generation, Concept Selection, Concept Embodiment, and Design Refinement. In the Problem Understanding phase, the team conducted extensive research on patents, codes and standards, user needs, design metrics, and project management. This foundational research was critical to ensure all aspects were considered before beginning the building process. User needs were identified …

Mems 411: Diving Surface Breaker, Chandler Gartner, Freddy Phillips, Maya Sumra, Olivia Slemmer

Mechanical Engineering Design Project Class

We have been recruited by the WashU diving team to design and construct a surface breaker for the Millstone Pool so the divers can have an affordable way to stay safe while practicing dives.

Mems 411: Timed Mosquito Egg Container Design Project, Paige Warren, Witt Ciesla, Ethan Sobel

Mechanical Engineering Design Project Class

The goal of this project is to design and construct a device that allows for the controlled study of mosquito egg-laying behavior in response to artificial light and temperature variations. Specifically, the device will limit access to cups of standing water, which serve as egg-laying sites, to preprogrammed times of day over a 7-day period.
The device should ensure the following:

• Control Access: The container should be open and closed at predetermined intervals, allowing mosquitoes to access the cups of standing water only during these times.
• Programmability: It should be easy for a novice to specify the opening and closing …

Mems 411: Ball Bearing Sorter, Abdissa Effa, Juliet Whitehead, Ayub Shifa

Mechanical Engineering Design Project Class

The challenge is to design and fabricate a compact device capable of autonomously sorting and transporting ball bearings of varying materials (chrome steel, brass, nylon) and sizes (¼” and ½”) into designated packaging stations. The device must operate efficiently, accurately, and within the constraints of a 20x20x20-inch enclosure, meeting industrial assembly line standards of speed and precision while minimizing human intervention. It aims to address the need for high-rate sorting systems in manufacturing environments, ensuring accurate material identification and classification for streamlined operations.

Mems 411: Asme Ball Bearing Sorter, Ryan Lively, Joseph Huster, Wil Collins

Mechanical Engineering Design Project Class

The ASME Student Design Competition focused on the design and construction of a ball bearing sorter. This ball bearing sorter must be capable of sorting 2 sizes of ball bearings, being 1/2 inch and 1/4 inch. For each size, there are 3 different bearing materials, brass, steel, and acetal plastic. The device is intended to have the bearings fed into a hopper, and then fully autonomously sort the bearings. The autonomous sorting was to transport the various bearings into 6 different packing stations, one for each size and material bearing. These packing stations must be easily removable. This design project …

Mems 411: Automated Assistive Toilet, Alex Scaff, Kenna Mcgahren, Daniel Sibley

Mechanical Engineering Design Project Class

How do we make toilets more accessible for all people - regardless of physical, mental, emotional impediments - while also ensuring simplicity and cost-effectiveness? Utilizing sensors, our toilet device is designed to automatically open and close the toilet lid upon approach, increasing ease of use and general hygiene of the user while being friendly to those who struggle with certain disabilities or impairments.

Mems 411: Adjustable Desk, Catryn Cattoor, Natalia Pilpil, Jamie Burgasser, Adam Wong

Mechanical Engineering Design Project Class

Design and create a desk for a special education classroom of kindergarteners to third graders. The desk needs slanting capabilities, wheel chair accessibility, raising/lower capabilities, distraction prevention capabilities, and light board capabilities. These capabilities need to be configurable for students with different needs. This desk also needs to be very durable, safe, and mobile. The main motivation for this project is the desire to provide the teacher and her students with a single, cost-effective product that is safe, easy to use, and meets their desired needs.

Mems 411: Group V Ball Bearing Sorter, Matthew Hernandez, Sean Huffert, Ethan Delair

Mechanical Engineering Design Project Class

After a semester of hard work, Team V is proud to unveil its finished prototype for the 2024-2025 ASME Student Design Competition. The theme of this challenge was "Assembly Line Sorting and Packaging." The goal of this challenge was to make a device able to satisfy the criteria of sorting between six different bearings of different sizing and material properties, and meeting spatial and time limitations. This device needed to be fast, accurate, compact, and able to sort in bulk. Team V feels like we have met most of these requirements with our final design prototype. For this project, a …

Mems 411: Rc Plane Mount For Cfd Validation, Jake Schwartz, Margot Jay, Ian Torres, Sam Ehrman

Mechanical Engineering Design Project Class

Washington University in St. Louis’ Design/Build/Fly team (WashU DBF) participates in an annual international competition with over 100 teams where they create a Remote Control (RC) plane that can perform various missions. One of the difficulties in developing a plane each year is testing the forces on the plane. Currently, Ansys and XFLR5 are used to create computational fluid dynamics (CFD) models for the plane. CFD modeling simulates air flow over the plane’s wings to analyze how to optimize the aircraft’s aerodynamics. While this is a useful strategy to predict the plane’s theoretical performance, WashU DBF Technical President, Eleni Kambouris, …

Mems 411: Mini Syringe Pump, Rachel Foulk, Braxton Hart, Camilo Hernandez

Mechanical Engineering Design Project Class

In many research and medical settings, small amounts of liquids are dispensed using syringes. Very often, syringe pumps like those shown in the left image, are used to control the amount (i.e., flow rate) of dispensed/collected fluid. There are single- or multi-style syringe pumps; the one shown is single-style; multi-style have 2-8 parallel syringes that are all pushed/pulled at the same flow rate. However, these syringe
pumps are bulky and heavy, making them impractical for many experimental setups. Commercial alternatives include very expensive syringe pumps with remote dispensers. Furthermore, it is often necessary to have two syringe pumps operate in …

Money Laundering Transactions Chronology Analysis Using Artificial Intelligence, Marwan Alawadhi

Theses

Money laundering is one of the most significant threats for the financial systems of the world, as it promotes other crimes and destabilizes the economy. This thesis presents an enhanced analysis of AI and ML on financial transaction data for the identification of patterns that relate to money laundering. It uses techniques like the Isolation Forest for the identification of outliers and clustering techniques like K-means and DBSCAN for identification of unusual transaction patterns across the four high risk countries that include United States, United Kingdom, Japan and Italy. The preprocessed dataset included different types of transactions like cross-border transactions, …

Chimes: December 9, 2024, Calvin University

Chimes

“That’s not true inclusion:” For disabled students, full campus accessibility remains elusive by Sarah Sparling

Umm al-Jimal archaeological site added to UNESCO World Heritage by Grace Buller and Elisabeth Stevens

2025 January Series sees restructure and big names by Graham Kort

Changes to dining hall hours, staffing benefits leave students broadly dissatisfied by Maya Oeverman

Making worship more accessible: A Q&A with Eleanor Plutz about ASL chapel interpretation by Anna Caruso

“The Holy Spirit Made Me Dance” by Natasha Jayaputra

Inference For Regression With Variables Generated By Ai Or Machine Learning, Laura Battaglia, Timothy Christensen, Stephen Hansen, Szymon Sacher

Cowles Foundation Discussion Papers

It has become common practice for researchers to use AI-powered information retrieval algorithms or other machine learning methods to estimate variables of economic interest, then use these estimates as covariates in a regression model. We show both theoretically and empirically that naively treating AI- and ML-generated variables as “data” leads to biased estimates and invalid inference. We propose two methods to correct bias and perform valid inference: (i) an explicit bias correction with bias-corrected confidence intervals, and (ii) joint maximum likelihood estimation of the regression model and the variables of interest. Through several applications, we demonstrate that the common approach …

Comparing Recovery Volumes Of Steady And Unsteady Injections Into An Aquifer Storage And Recovery Well, Saeid Masoudiashtiani, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Aquifer Storage and Recovery (ASR) can involve injecting available surface water into an unconfined aquifer and then extracting it to provide secondary water for irrigation. This study demonstrates a method for evaluating the appropriateness of steady injection versus unsteady injection for an assumed situation. In design, it can be important to affect the transient: the proportion of the injected water that would be subsequently extracted (versus that remaining in the aquifer) and the proportion within the extracted water that would be an injectate (versus ambient groundwater). These proportions can be predicted from the predicted value of an ASR well's Recovery …

Mae Enewsbrief July-Sept 2024, Department Of Mechanical And Aerospce Engineering, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.