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Articles 211 - 240 of 1825

Full-Text Articles in Engineering

Characterizing Brain And Skull Mechanics In The Minipig Using Magnetic Resonance Elastography, Shuaihu Wang Apr 2024

Characterizing Brain And Skull Mechanics In The Minipig Using Magnetic Resonance Elastography, Shuaihu Wang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Computational models and simulation are important tools to investigate the mechanisms underlying traumatic brain injury (TBI); their accuracy depends strongly on accurate model parameters, including the mechanical properties of the brain and its interactions with the skull. However, most existing TBI modeling studies are performed using material properties derived from animal tissue obtained after death. Magnetic resonance elastography (MRE) provides a non-invasive method for estimating the mechanical properties of soft tissue. The overall objective of this thesis is to characterize the biomechanical properties of brain tissue and brain-skull interface in the minipig by using MRE. This was achieved through pursuit …


Low Impedance, Durable, Self-Adhesive Hydrogel Epidermal Electrodes For Electrophysiology Recording, Naiyan Wu Apr 2024

Low Impedance, Durable, Self-Adhesive Hydrogel Epidermal Electrodes For Electrophysiology Recording, Naiyan Wu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Traditional electrodes used for electrophysiology recording, characterized by their hard, dry, and inanimate nature, are fundamentally mismatched with the soft, moist, and bioactive characteristics of biological tissues, leading to suboptimal skin-electrode interfaces. Hydrogel materials, mirroring the high water content and biocompatibility of biological tissues, emerge as promising candidates for epidermal electronic materials due to their adjustable physicochemical properties. However, challenges such as inadequate electrical conductivity, elevated skin impedance, unreliable adhesion in moist conditions, and performance decline from dehydration have significantly restricted the efficacy and applicability of hydrogel-based electrodes. In this thesis, we report a high-performance hydrogel epidermal electrode patch for …


Electrochemical Phosphorus Recovery From The Anaerobically Digested Sludge: Mechanism, Performance, Application, And Solids Disposal, Zixuan Wang Apr 2024

Electrochemical Phosphorus Recovery From The Anaerobically Digested Sludge: Mechanism, Performance, Application, And Solids Disposal, Zixuan Wang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Phosphorus (P) is life’s bottleneck element and an essential nutrient for food production. However, phosphate rock is a non-renewable resource and its geological distribution is highly uneven, making P recovery a crucial step for a circular economy. Approximately 55% of mined phosphorus ends up in centralized wastewater treatment plants (WWTPs), where up to 90% is captured in the sludge. This sludge, treated in anaerobic digesters to produce anaerobically digested sludge (ADS), emerges as a viable secondary source for phosphorus recovery. Recovering phosphorus from ADS typically involves leaching and separation. Leaching mobilizes phosphates from sludge solid phase into a liquid phase, …


Resolving The Nanoscale Structure Of Β-Sheet Peptide Self-Assemblies Using Single-Molecule Orientation–Localization Microscopy, Weiyan Zhou, Conor L. O'Neill, Tianben Ding, Oumeng Zhang, Jai S. Rudra, Matthew D. Lew Mar 2024

Resolving The Nanoscale Structure Of Β-Sheet Peptide Self-Assemblies Using Single-Molecule Orientation–Localization Microscopy, Weiyan Zhou, Conor L. O'Neill, Tianben Ding, Oumeng Zhang, Jai S. Rudra, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

Synthetic peptides that self-assemble into cross-β fibrils are versatile building blocks for engineered biomaterials due to their modularity and biocompatibility, but their structural and morphological similarities to amyloid species have been a long-standing concern for their translation. Further, their polymorphs are difficult to characterize using spectroscopic and imaging techniques that rely on ensemble averaging to achieve high resolution. Here, we utilize Nile red (NR), an amyloidophilic fluorogenic probe, and single-molecule orientation-localization microscopy (SMOLM) to characterize fibrils formed by the designed amphipathic enantiomers KFE8L and KFE8D and the pathological amyloid-beta peptide Aβ42. Importantly, NR SMOLM reveals the helical (bilayer) …


6d Single-Fluorogen Orientation-Localization Microscopy For Elucidating The Architecture Of Beta-Sheet Assemblies And Biomolecular Condensates, Tingting Wu, Weiyan Zhou, Jai S. Rudra, Rohit V. Pappu, Matthew D. Lew Mar 2024

6d Single-Fluorogen Orientation-Localization Microscopy For Elucidating The Architecture Of Beta-Sheet Assemblies And Biomolecular Condensates, Tingting Wu, Weiyan Zhou, Jai S. Rudra, Rohit V. Pappu, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

We develop six-dimensional single-molecule orientation-localization microscopy (SMOLM) to measure the 3D positions and 3D orientations simultaneously of single fluorophores. We show how careful optimization of phase and polarization modulation components can encode phase, polarization, and angular spectrum information from each fluorescence photon into a microscope’s dipole-spread function. We used the transient binding and blinking of Nile red (NR) to characterize the helical structure of fibrils formed by designed amphipathic peptides, KFE8L and KFE8D, and the pathological amyloid-beta peptide Aβ42. We also deployed merocyanine 540 to uncover the interfacial architectures of biomolecular condensates.


Engineering Mussel Foot Protein 5 (Mfp5) For Enhanced Adhesive Performance In Tendon And Bone Repair, Ziyue Zhu Jan 2024

Engineering Mussel Foot Protein 5 (Mfp5) For Enhanced Adhesive Performance In Tendon And Bone Repair, Ziyue Zhu

McKelvey School of Engineering Graduate Student Theses & Dissertations

This study explores the development of Mussel Foot Protein 5 (MFP5) bioadhesives to improve tendon-to-tendon and tendon-to-bone adhesive outcomes. MFP5, known for its underwater adhesive properties, was synthesized using recombinant techniques and optimized through coacervation and cross-linking. Adhesion tests demonstrated the superior performance of the optimized MFP5 adhesive on the tendon and bone samples. Improved protein concentration testing and purification methods enhanced MFP5 yield and consistency. Future research will focus on further standardization, exploring alternative purification methods, and evaluating the adhesive's performance in animal models. This study lays a foundation for developing robust MFP5-based bioadhesives, potentially revolutionizing surgical repair techniques …


Data-Driven Approaches To System Analysis And Control Design, Minh Vu Dec 2023

Data-Driven Approaches To System Analysis And Control Design, Minh Vu

McKelvey School of Engineering Graduate Student Theses & Dissertations

In this thesis, we study the integration of data and computational methods in nonlinear system analysis and control design. In the first part of this thesis, we develop a constructive framework for designing a set of candidate functions from data such that desired control-theoretic conditions are satisfied. This new design framework is aimed at offering a general data-driven approach to a number of problems in systems and control, including stability analysis, stabilization, and safety-critical control designs. The second half of the thesis focuses on the specific problem of designing a point-to-point steering, which is often considered in many practical control …


Decentralized Computing For Reliable Home Automation, Rahav Dor Dec 2023

Decentralized Computing For Reliable Home Automation, Rahav Dor

McKelvey School of Engineering Graduate Student Theses & Dissertations

Smart homes are distributed systems that should provide reliable home automation services. Distributed controllers have been used to improve the reliability of smart homes. However, despite the redundancy in controllers, the reliability of smart homes is hindered by the unreliable network infrastructure comprising home Wi-Fi and low-power wireless networks. As a result, smart homes cannot be trusted with much more than casual automation to date. This dissertation identifies the limitations of traditional fault-tolerant approaches that require inter-controller coordination over an unreliable network infrastructure. A new class of decentralized control paradigm named Banyan, with fully autonomous controllers, is introduced by this …


Estimating And Detecting Slow-Wave Events In Eeg Signals, Zhenghao Xiong Dec 2023

Estimating And Detecting Slow-Wave Events In Eeg Signals, Zhenghao Xiong

McKelvey School of Engineering Graduate Student Theses & Dissertations

Slow wave activity (SWA) is an electroencephalogram (EEG) pattern commonly occurring during anesthesia and deep sleep, and is hence a candidate biomarker to quantify such states and understand their connection to various phenotypes. SWA consists of individual slow waves (ISW), high-amplitude deflections lasting for approximately 0.5 to 1 second, and occurring quasi-periodically. This latter fact poses a challenge for conventional power spectral density EEG analysis methods that perform best when there is persistency of oscillatory activity. In this work, we pursue a time-domain detection framework for identifying and quantifying ISWs as a metric for SWA. Our method works, in essence, …


Commercial Adsorbents For Co2 Removal For Biogas Upgradation: An Experimental Study, Aakriti Bagla Dec 2023

Commercial Adsorbents For Co2 Removal For Biogas Upgradation: An Experimental Study, Aakriti Bagla

McKelvey School of Engineering Graduate Student Theses & Dissertations

No abstract provided.


An Apparatus To Quantify Lengthwise Flexural Rigidity Profiles Of Endovascular Devices, Charles B. Suskin Dec 2023

An Apparatus To Quantify Lengthwise Flexural Rigidity Profiles Of Endovascular Devices, Charles B. Suskin

McKelvey School of Engineering Graduate Student Theses & Dissertations

Endovascular procedures require access to distal anatomical sites through the vasculature using catheters and guidewires. Quantitative frameworks for device behavior during procedures hold the potential to drive device design through greater understanding of the mechanical behavior of endovascular devices, and offer the potential to personalize care based on a patient's particular vascular anatomy. However, data that would facilitate this technology are lacking, partly due to undisclosed material properties from manufacturers and partly due to the intricate variations along the length of each device due to material changes and the intersections between them. We developed a three-point bend test methodology on …


Enhanced Fabrication Of Microdroplet Generator Nozzle Arrays: Optimizing Koh Etching For Microfluidic Applications, Hongyu Bai Dec 2023

Enhanced Fabrication Of Microdroplet Generator Nozzle Arrays: Optimizing Koh Etching For Microfluidic Applications, Hongyu Bai

McKelvey School of Engineering Graduate Student Theses & Dissertations

Ultrasonic microdroplet generators are useful devices with broad applications ranging from aerosolized drug delivery to three-dimensional (3D) printing-based additive manufacturing. One such technology comprises a microfabricated array of nozzles with droplet production driven by a piezoelectric transducer. The present study focuses on refining a critical fabrication step, anisotropic wet etching of pyramidal nozzles using a basic potassium hydroxide (KOH) solution. Given the integral role of nozzle geometry in device operation, high-precision techniques including Reactive Ion Etching (RIE), Deep Reactive Ion Etching (DRIE), and KOH wet etching were employed. A tapering geometry is preferred for acoustic wave focusing and efficient droplet …


Design Of Human Serum Albumin And Adenovirus Conjugation Via Catcher/Tag Molecular Glue, Peijie Zhao Dec 2023

Design Of Human Serum Albumin And Adenovirus Conjugation Via Catcher/Tag Molecular Glue, Peijie Zhao

McKelvey School of Engineering Graduate Student Theses & Dissertations

Adenovirus (Ad) has been the ideal cargo delivery mechanism, and its moderate immunological response makes it ideal for in vivo gene therapies since its discovery in 1953. However, the robust immunogenicity of the Ad capsid and low vaccine absorption via mucous membranes and epithelium put a limit on the process of developing intranasal vaccines. Efforts are being made to enhance the effectiveness of Ad vectors and numerous studies have demonstrated the remarkable capacity of human serum albumin (HSA) to extend plasma half-life and facilitate targeted intranasal delivery. In this study, we devised an innovative method for employing the Catcher/Tag molecular …


Improving And Integrating Quantitative Single Cell Spatial Biology For Theranostic Medicine, Peng Lu Dec 2023

Improving And Integrating Quantitative Single Cell Spatial Biology For Theranostic Medicine, Peng Lu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Disease states are the result of a complex interplay of many different cell types interacting in close proximity in the context of often heterogeneous tissues. Alpha particles are drawing intense research and clinical interest because of their potent cytotoxic effects and their short path lengths. Analyzing the dose distribution and tissue micro-environment for alpha therapy plays a key role in predicting the efficacy of this targeted radiotherapy. However, to date there have been no direct on-tissue analytical methods for alpha dose distributions and the corresponding tissue microenvironments.

Therefore, we have developed a pipeline to overcome this limitation by utilizing quantitative …


Real-Time Analysis Of Aerosol Size Distributions With The Fast Integrated Mobility Spectrometer (Fims), Daisy Wang Dec 2023

Real-Time Analysis Of Aerosol Size Distributions With The Fast Integrated Mobility Spectrometer (Fims), Daisy Wang

McKelvey School of Engineering Graduate Student Theses & Dissertations

The Fast Integrated Mobility Spectrometer (FIMS) has emerged as an innovative instrument in the aerosol science domain. It employs a spatially varying electric field to separate charged aerosol particles by their electrical mobilities. These separated particles are then enlarged through vapor condensation and imaged in real time by a high-speed CCD camera. FIMS achieves near 100% detection efficiency for particles ranging from 10 nm to 600 nm with a temporal resolution of one second. However, FIMS’ real-time capabilities are limited by an offline data analysis process. Deferring analysis until hours or days after measurement makes FIMS' capabilities less valuable for …


Mems 411: Robot Mini Golf - Striker, Jasmine Davy, Maya Charak, Ilias Bouchibti Oct 2023

Mems 411: Robot Mini Golf - Striker, Jasmine Davy, Maya Charak, Ilias Bouchibti

Mechanical Engineering Design Project Class

The goal of this project was to design a remote-controlled device that is able to putt and chip a golf ball to achieve several obstacles. This project was designed using the guidelines for the ASME design challenge. The guidelines for this challenge required that the striker fit in a half-meter box, have the capacity to both putt and chip a ball, and be able to overcome obstacles, such as getting up a half pipe onto an elevated surface, clear a 3” hoop, and traverse an inclined ramp. These guidelines had to be met while maintaining a budget of $400.


Mems 411: Vehicle Entry Aid, Sara Wargo, Joshua Doro, Benjamin Swonger, Justin Stohlman Oct 2023

Mems 411: Vehicle Entry Aid, Sara Wargo, Joshua Doro, Benjamin Swonger, Justin Stohlman

Mechanical Engineering Design Project Class

Handicapped individuals such as those with prosthetic legs or diabetes can struggle greatly with entering large vehicles such as trucks. In this struggle, a client uses a rigid step stool with a rope tied through it to lift himself and then the stool into the vehicle. This report outlines an initiative to design and manufacture a better solution to this problem. A collapsible, two-step step stool was fabricated with a spring loaded retraction system. The design process for this solution is outline from start to finish, showing the extensive thought process that was followed to create the final product.


Mems 411: Motorized Striker, Joseph Crossin, Joana Hadzhilazova, Connor Petersen, Vyas Venkataraman Oct 2023

Mems 411: Motorized Striker, Joseph Crossin, Joana Hadzhilazova, Connor Petersen, Vyas Venkataraman

Mechanical Engineering Design Project Class

This report follows the design and prototyping process for Group B5’s Senior Mechanical Engineering Design Project. Group B5 was tasked with designing a motorized golf striker to perform in the ASME design challenge. This report lays out the progression of the design process beginning with Problem Understanding, then Concept Generation, Concept Selection, Concept Embodiment, Design Refinement, and concludes with an assessment of the final prototype.


Mems 411: Mini-Golf Robot Vehicle, Catherine Huang, Shicheng Li, Colin Chen, Maximilian Li Oct 2023

Mems 411: Mini-Golf Robot Vehicle, Catherine Huang, Shicheng Li, Colin Chen, Maximilian Li

Mechanical Engineering Design Project Class

The primary objective of the project is to develop a remote-controlled vehicle capable of completing a round of mini golf as part of the ASME Student Design Competition. The vehicle’s functionalities are categorized into driving and golf-ball striking. Our group is specifically responsible for the former aspect.

The remote-controlled vehicle is expected to traverse through the designated competition field and exhibit the ability to maneuver between and over obstacles, including a high wall and a low platform. Our design should adhere to the competition regulations set forth by ASME SDC, which include specific criteria for the vehicle such as size …


Mems 411: B2 Striker Group Final Design Report, Jacob Rapoza, Ian M. Veserra, Alex J. Webert, Keaton Porch Oct 2023

Mems 411: B2 Striker Group Final Design Report, Jacob Rapoza, Ian M. Veserra, Alex J. Webert, Keaton Porch

Mechanical Engineering Design Project Class

Design a golf striker that can accomplish all the holes set forth by the ASME 2023 design competition and could be attached to a robot without major design modifications.


Mems 411: Medical Clamp, Edis Skampo, Rodery Gonzalez, Sokcheatra Samrith, Sean Lucas Oct 2023

Mems 411: Medical Clamp, Edis Skampo, Rodery Gonzalez, Sokcheatra Samrith, Sean Lucas

Mechanical Engineering Design Project Class

The goal of the team was to design a plier that would be able to clamp down a medical clamp used for a dialysis machine. Ideally the plier should be able to clamp down 3 medical clamps on three separate dialysis tubes in less than 5 seconds, reduce the force required to clamp those clamps by 4 times, and weigh less than 113 grams. The product design was broken down into 3 separate concepts, with four options for each component. The most preferable option of each component was chosen and several risk factors were taken in consideration so that the …


Mems 411: Dialysqueeze, Ranch Kimball, Maeve Lomax, Tyler Carlson Oct 2023

Mems 411: Dialysqueeze, Ranch Kimball, Maeve Lomax, Tyler Carlson

Mechanical Engineering Design Project Class

Design a device to reduce occupational fatigue injuries suffered by nurses who must manually clamp and unclamp tubing for dialysis machines. This device was designed for MEMS 411 Senior Design.


Mems 411: Asme Design Challenge Hitting Apparatus, Benjamin Deobald, Curtis Hung, Joseph Kodsi, Andrew Sheen Oct 2023

Mems 411: Asme Design Challenge Hitting Apparatus, Benjamin Deobald, Curtis Hung, Joseph Kodsi, Andrew Sheen

Mechanical Engineering Design Project Class

Develop a specialized hitting mechanism for the modified 2023 ASME Design Competition's mini-golf robot challenge. The mechanism needs to accurately chip and putt golf balls, ensuring compatibility for mounting onto another team's vehicle chassis. Key considerations include weight, form-factor, remote operation ease, and endurance within a $400 budget. The mechanism must adhere to competition rules, stopping before hitting, non-operation during ball contact except for relocation, and transport of the ball to designated areas.


Mems 411: B8-Golf Striker, Theodore Francis Anastasoff, Mitchell Oswald Shannon, Aidan Richard Tierney, Nick Alexander Vazquez Oct 2023

Mems 411: B8-Golf Striker, Theodore Francis Anastasoff, Mitchell Oswald Shannon, Aidan Richard Tierney, Nick Alexander Vazquez

Mechanical Engineering Design Project Class

Robots are useful for a variety of tasks and can be very fun to make. For our design of a golf striker robot, we will use our knowledge of core mechanical engineering principles to achieve our goal of a functional end product. Our research into existing devices of such nature showed us how useful these robots are in the golf industry. Whether it is to see how far technology ad machine learning has evolved or to test how golf equipment will stand under duress, these robots provide useful feedback for companies and players. Seeing devices like Golfi, LDRICK, and the …


Mems 411: Heavy Cart Ramp Assistant, Caelyn Walton-Macaulay, Eniya Jaber, Nashleen Salazar Rodriguez Oct 2023

Mems 411: Heavy Cart Ramp Assistant, Caelyn Walton-Macaulay, Eniya Jaber, Nashleen Salazar Rodriguez

Mechanical Engineering Design Project Class

Some experiments in Prof. Kathy Flores’s lab use argon gas, which is stored in a
big tank. A scale is used to determine how much gas is left in the tank.
To get the tank onto the scale, a person must roll it up a short, fairly steep ramp
onto the scale platform. There is a ramp on the other side of the scale too, so
overshooting the platform causes the ramp to crash into the wall (the lab has taped a foam bumper onto the wall to mitigate this). Once finished, the cart is rolled
back down the ramp, …


Mems 411: Pinch Clamp Clipper, Mackenzie Molina, Jaimie Lin, Oliver Avery Oct 2023

Mems 411: Pinch Clamp Clipper, Mackenzie Molina, Jaimie Lin, Oliver Avery

Mechanical Engineering Design Project Class

The purpose of this project was to design a device to take stress off the CMC thumb joint when applying pinch clamps to dialysis tubing. The motivation was to reduce the risk of osteoarthritis in renal care nurses. Sydney Livermore, an OT student at McMaster University, identified that nurses who had to routinely clip pinch clamps on dialysis tubes were at risk of developing osteoarthritis in their CMC joints. She asked us to design a device that could clip the pinch clamps while reducing the force required to do so. The device needed to be able to clip the clamps …


Mems 411: Heavy Cart Ramp Assistant, Ethan Current, Kevin Xiong, Nick Zanchi Oct 2023

Mems 411: Heavy Cart Ramp Assistant, Ethan Current, Kevin Xiong, Nick Zanchi

Mechanical Engineering Design Project Class

Dr. Katharine Flores has a heavy Argon tank that needs to be put on a scale and wants a device that a single person can operate to assist them in that task.


Mems 411: In-Beach Pressure Sampler Design Report, Alex Mccormick, Mark Lipkin, Nirvan Patel Masini, Austin Bick Oct 2023

Mems 411: In-Beach Pressure Sampler Design Report, Alex Mccormick, Mark Lipkin, Nirvan Patel Masini, Austin Bick

Mechanical Engineering Design Project Class

Claudio would like a device to put into the beach sand, around nest-depth, to
measure and record data that can determine pressure as waves crash and recede.


Mems 411: Pinskee Ball - A Work-Energy Demo, Kyle Puckett, Helena Teixeira-Dasilva, Seth Kleinberg, Sydney Norstad Oct 2023

Mems 411: Pinskee Ball - A Work-Energy Demo, Kyle Puckett, Helena Teixeira-Dasilva, Seth Kleinberg, Sydney Norstad

Mechanical Engineering Design Project Class

The goal of our project is to develop a fun and engaging Work-Energy Demo for Dr. James Potter of Washington University in St. Louis and a Science Center or Children's Museum. We aim to teach 6 - 10 year old children about Work-Energy and Energy Transfer in a fun, engaging, and competitive way by using an arcade style machine. The following project is intended to be a Pinball-Based Conservation of Energy Demo/Game for a Science Museum. Using both pinball and skeeball characteristics, this device will give kids thorough knowledge of work energy systems in a fun and interactive way. The …


Mems 411: Bamboo Clamping Device, Grace Chen, Anya Gupta, Yosef Weiss Oct 2023

Mems 411: Bamboo Clamping Device, Grace Chen, Anya Gupta, Yosef Weiss

Mechanical Engineering Design Project Class

The objective of this design project was to create an automatic clamping machine to
keep bamboo bundles tight during lashing. Currently, manual clamping and lashing
of bamboo require simultaneous user effort, posing challenges in terms of efficiency
and safety. Our project introduces a mechanical and automatic clamping tool,
designed to significantly alleviate the physical strain on users and enhance overall
safety. This report details two primary designs of solutions to this problem. The
first is a motor-tightened hose clamp controlled via a three-way switch. The second
design is a claw clamp with an inflatable pouch used to pin the bamboo …