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Scitechatorium Exhibit, Adam Khan, Cole Busch, Logan Femling, Alan Onuma Jun 2024

Scitechatorium Exhibit, Adam Khan, Cole Busch, Logan Femling, Alan Onuma

Mechanical Engineering

This document outlines the final stages of development and analysis of our interactive children’s exhibit for the Bellevue-Santa Fe Charter School’s SciTechatorium. We will showcase the final form of our ball and track display, giving a detailed look at each component and subsystem.

To describe how our final prototype will be built we have included a detailed manufacturing summary for our design. Our models have been designed with manufacturability in mind, and we have outlined which processes were used to produce all our parts.

There are also detailed descriptions of testing that were conducted to verify the performance of the …


Acoustic Activation Imaging With Intravenous Perfluoropropane Nanodroplets Results In Selective Bioactivation Of The Risk Area, S. Li, C. Chen, J. Lof, E. A. Stolze, J. Sklenar, X. Chen, J. J. Pacella, F. S. Villanueva, T. O. Matsunaga, E. Carr Everbach, S. J. Radio, S. N. Westphal, S. Shiva, F. Xie, X. Leng, T. R. Porter Jun 2024

Acoustic Activation Imaging With Intravenous Perfluoropropane Nanodroplets Results In Selective Bioactivation Of The Risk Area, S. Li, C. Chen, J. Lof, E. A. Stolze, J. Sklenar, X. Chen, J. J. Pacella, F. S. Villanueva, T. O. Matsunaga, E. Carr Everbach, S. J. Radio, S. N. Westphal, S. Shiva, F. Xie, X. Leng, T. R. Porter

Engineering Faculty Works

Background: Acoustically activatable perfluoropropane droplets (PD) can be formulated from commercially available microbubble preparations. Diagnostic transthoracic ultrasound frequencies have resulted in acoustic activation (AA) predominately within myocardial infarct zones (IZ). Objective: We hypothesized that the AA area following acute coronary ischemia/reperfusion (I/R) would selectively enhance the developing scar zone, and target bioeffects specifically to this region. Methods: We administered intravenous PD in 36 rats and 20 pigs at various stages of myocardial scar formation (30 minutes, 1 day, and 7 days post I/R) to determine what effect infarct age had on the AA within the IZ. This was correlated with …


Polypropylene As Partial Fine Aggregate Substitute In Concrete, Samuel E. Royston, Chrisitan G. Achkar, Nicholas B. Tabarez Jun 2024

Polypropylene As Partial Fine Aggregate Substitute In Concrete, Samuel E. Royston, Chrisitan G. Achkar, Nicholas B. Tabarez

Architectural Engineering

The objective of this project is to discover a structurally effective method in repurposing recyclable plastic waste through its partial substitution for traditional fine aggregate in concrete.

Results obtained from analysis indicate a 25 percent compressive strength reduction with polypropylene at a 10 percent partial substitution for total sand content. This material successfully performed as an alternative, presenting a ductile mode of failure.

Three material alternatives - polypropylene, polyethylene, and rubber - were substituted for a percentage of sand. These materials underwent concrete cylinder crushing tests to determine their ultimate crushing strength, with the intent of identifying the most effective …


Advances In Bone And Orthopedics 2024 Edition, Jean-Philippe Berteau, Laurent Pujo-Menjouet Jun 2024

Advances In Bone And Orthopedics 2024 Edition, Jean-Philippe Berteau, Laurent Pujo-Menjouet

Publications and Research

We are delighted to present the latest edition of ”Advances in Bone and Orthopedics,” a comprehensive compilation of pioneering research and innovative developments in the field. This volume brings together a selection of peer-reviewed abstracts from BONITOS 2024, the Fourth Season of the Bone and Orthopedics Interdisciplinary Symposium, held on May 31st, 2024, at the College of Staten Island in New York. This symposium, a hallmark event in the calendar of professionals dedicated to bone health and orthopedic excellence. The contributions within this volume reflect the breadth and depth of research presented at BONITOS 2024. These abstracts represent cutting-edge studies …


Consumption And Waste For Hydrating Workers With Single Use Plastic Bottles, James Colnett Jun 2024

Consumption And Waste For Hydrating Workers With Single Use Plastic Bottles, James Colnett

Construction Management

The construction industry significantly contributes to environmental waste, notably through the extensive use of plastic water bottles for hydrating field personnel. This case study investigates the hydration practices of a midsize construction company in the Bay Area, focusing on the volume of plastic waste generated and potential sustainable alternatives. Data were collected via surveys sent to 15 employees, revealing that approximately 130,416 plastic bottles are used annually across 11 project sites. Despite the convenience and compliance with OSHA regulations, the reliance on single-use plastic bottles presents severe environmental and health concerns, such as resource depletion and microplastic pollution. Survey results …


Performance Analysis Of Underground-To-Aboveground Communication In Agricultural Iot Networks, Irfana Ilyas Manzil Jun 2024

Performance Analysis Of Underground-To-Aboveground Communication In Agricultural Iot Networks, Irfana Ilyas Manzil

Theses

This thesis investigates the potential of LoRa, a low-power, wide-area networking technology, for establishing reliable communication between underground sensors and aboveground infrastructure. We comprehensively analyze LoRa's performance in both single-hop and multi-hop configurations, considering the impact of diverse environmental factors such as soil composition, moisture content, underground transmission distance, and path loss on signal propagation. We delve into the crucial role of the spreading factor (SF) within the LoRa communication system, analyzing its influence on network performance. Furthermore, we develop a comprehensive mathematical model for bit error rate (BER) under various channel conditions, including additive white Gaussian noise (AWGN) and …


An Analysis Of Indoor Air Quality At Cal Poly For Sensor Design, Isabella M. Santi Jun 2024

An Analysis Of Indoor Air Quality At Cal Poly For Sensor Design, Isabella M. Santi

Master's Theses

Prior research has shown that indoor air quality (IAQ) impacts cognitive performance. At Cal Poly, many older buildings are unable to maintain appropriate IAQ because of their outdated ventilation systems and the increasing number of students in the rooms. This work analyzes the IAQ of different buildings at Cal Poly, with a focus on Building 20. Carbon dioxide, temperature, and relative humidity inside classrooms are collected using an integrated circuit sensor and a microcontroller. A total of 38 hours of data was collected, with 22 of those hours in Building 20 specifically. We find that unlike temperature and relative humidity, …


Naturify 2300, Yarina Yiwei Dai Jun 2024

Naturify 2300, Yarina Yiwei Dai

Masters Theses

In my art practice, I explore the interplay between human desires to manipulate and anthropomorphize nature, as seen in the technological augmentation of plants and living entities. This investigation delves into how this intersection, alongside empathy towards these creations, contributes to fears of uncontrollability and the risks of addiction and excessive dependence on technology.

Bioengineering and genetic modification have cultivated unprecedented developments, allowing humans to manipulate the fundamental building blocks of life. My research speculates on this technology further, modifying the genetic code of organisms and creating bioengineered wearable entities with enhanced traits or entirely new functionalities. The primary objective …


Architecture As A Carbon-Based Practice, Qixin Yu Jun 2024

Architecture As A Carbon-Based Practice, Qixin Yu

Masters Theses

Carbon serves as both a silent protagonist and a looming antagonist in the narrative of architecture, shaping not only the physical structures we inhabit but also the ecological legacy we leave behind.

Centuries of human exploitation of the environment have led to climate and material crises. Shifting this dynamic requires action at micro (matter), meso (material), and macro (materiality) levels. Biogenic materials offer significant potential for carbon sequestration and present opportunities for the building industry to collaborate with nature rather than merely extract from it.

This thesis establishes a research and manufacturing practice that prioritizes material innovation, carbon sequestration, environmental …


Coolsplint: Inflammation Reduction Accessory, Laura C. Denney, Winston H. Giang, Aanchal Singh Jun 2024

Coolsplint: Inflammation Reduction Accessory, Laura C. Denney, Winston H. Giang, Aanchal Singh

Biomedical Engineering

This document outlines a project sponsored by Elizabeth Mentel and Michael Clausson that addresses the shortcomings in current splinting options, particularly for wrist fractures in elderly patients. Stakeholders include clinicians, patients, and emergency medical technicians. Multiple improvements can be made to current splinting options to help alleviate inflammation along with splint versatility, affordability, accessibility, and ease of use. After determining the critical customer requirements, the primary objective of this project was to find a way to manage inflammation. The project explores existing splinting solutions and proposes a new design that utilizes cooling rods to reduce inflammation. The document reviews various …


Cervical Spinal Cord Angiography And Vessel-Selective Perfusion Imaging In The Rat, Seongtaek Lee, Brian Schmit, Shekar N. Kurpad, Matthew D. Budde Jun 2024

Cervical Spinal Cord Angiography And Vessel-Selective Perfusion Imaging In The Rat, Seongtaek Lee, Brian Schmit, Shekar N. Kurpad, Matthew D. Budde

Biomedical Engineering Faculty Research and Publications

Arterial spin labeling (ASL) has been widely used to evaluate arterial blood and perfusion dynamics, particularly in the brain, but its application to the spinal cord has been limited. The purpose of this study was to optimize vessel-selective pseudocontinuous arterial spin labeling (pCASL) for angiographic and perfusion imaging of the rat cervical spinal cord. A pCASL preparation module was combined with a train of gradient echoes for dynamic angiography. The effects of the echo train flip angle, label duration, and a Cartesian or radial readout were compared to examine their effects on visualizing the segmental arteries and anterior spinal artery …


San Luis Obispo High School Ffa Barn Demolition: Disposal Of Material, Jake B. Schulman Jun 2024

San Luis Obispo High School Ffa Barn Demolition: Disposal Of Material, Jake B. Schulman

Construction Management

San Luis Obispo High School’s FFA program needed to upgrade its deteriorating pig barn, involving three key scopes of work: demolition of the existing structure, proper disposal of materials, and reconfiguration of pig pens and water lines. This project required skills in demolition, framing, and plumbing, all of which our team learned during construction management courses at Cal Poly. The demolition entailed the complete removal of a barn with metal roof panels, wood trusses, joists, studs, and plywood sheathing. Proper disposal of these materials was crucial and will be detailed in this paper, with a brief discussion on demolition and …


San Luis Obispo High School Ffa Barn Demolition: Demolition, Ryan Reza Manesh Jun 2024

San Luis Obispo High School Ffa Barn Demolition: Demolition, Ryan Reza Manesh

Construction Management

The San Luis Obispo High School FFA program required an upgrade to its swine enclosure including removal of the deteriorating pig barn. This project came in three unique scopes of work: demolition of the existing barn, proper disposal of materials, and reconfiguration of pig pens and water lines. This paper will cover specifically the demolition of the barn.. This phase of the project required skills in framing and plumbing, which our team had absorbed during specific construction management courses at Cal Poly. The reconfiguration included framing and securing a long span of fencing along the northern side of the project …


San Luis Obispo High School Ffa Swine Barn Demolition And Enclosure Reconfiguration, John F. Spurlock Jun 2024

San Luis Obispo High School Ffa Swine Barn Demolition And Enclosure Reconfiguration, John F. Spurlock

Construction Management

The San Luis Obispo High School (SLOHS) FFA program required an upgrade to its deteriorating swine barn. This project came in three unique scopes of work: demolition of the existing barn, proper disposal of materials, and reconfiguration of the enclosure and water lines. This paper will cover specifically the reconfiguration of the enclosures and the redesign of the watering system. This phase of the project required skills in framing and plumbing, which our team had absorbed during specific construction management courses at Cal Poly. The reconfiguration included framing and securing a long span of fencing along the northern side of …


Leaning Pine Arboretum Gazebo- Phase 1: Preconstruction, Layout, Material Procurement, Hunter Froud, Aleena Panchal Jun 2024

Leaning Pine Arboretum Gazebo- Phase 1: Preconstruction, Layout, Material Procurement, Hunter Froud, Aleena Panchal

Construction Management

This essay outlines the thorough preconstruction procedure that went into building a pavilion in the university's Leaning Pine Arboretum. Every step that our team took, from the preliminary surveying phase to the foundation laying prior to frame, is painstakingly planned and carried out. The main objective is to create a dynamic area that effortlessly combines education and recreation; it should be both a lively meeting place and a haven for students to study under cover. The team took a calculated risk to make sure our pre-construction phase was successful. This included carrying out thorough quantity takeoffs, keeping lines of communication …


San Luis Obispo High School Ffa Farm Chicken Coop Construction, Tara R. Keene Jun 2024

San Luis Obispo High School Ffa Farm Chicken Coop Construction, Tara R. Keene

Construction Management

This paper covers the construction process by a team of students from California Polytechnic State University, San Luis Obispo (Cal Poly) to provide a chicken coop for the San Luis Obispo High School FFA Farm. First initiated in Fall 2023, the project will replace the existing temporary chicken coops with a larger and more functional structure to house over 10 chickens. This paper focuses on the construction phase, but also briefly touches on the design and pre-construction phases. Through meetings with the client, the team of students developed a design that met the high school’s criteria and needs. Key features …


Network Slicing And Noma Enabled Mobile Edge Computing For Next-Generation Networks, Mohammad Arif Hossain May 2024

Network Slicing And Noma Enabled Mobile Edge Computing For Next-Generation Networks, Mohammad Arif Hossain

Dissertations

The advent of next-generation wireless networks ushers in a new era of potential, harnessing cutting-edge technologies like mobile edge computing (MEC), non-orthogonal multiple access (NOMA), and network slicing as pivotal drivers of transformation. Within this landscape, an innovative approach is proposed by introducing a NOMA-enabled network slicing technique within MEC networks. This approach aims to achieve multiple objectives: meeting stringent quality of service requirements, minimizing service latency, and enhancing spectral efficiency. By seamlessly integrating NOMA with network slicing in edge computing environments, significant reductions in overall latency are achieved, alongside ensuring optimal resource allocation for NOMA users. To address these …


Interaction Of Particles With Plasma And Shock Produced By Pulsed Spark Discharge, Shomik Mukhopadhyay May 2024

Interaction Of Particles With Plasma And Shock Produced By Pulsed Spark Discharge, Shomik Mukhopadhyay

Dissertations

Interactions of powders with high-temperature plasma and shockwaves occur in diverse scenarios, such as nuclear blasts, accidental industrial dust explosions, solid propellant combustion in explosive charges and when removing contaminants from surfaces. Electrostatic Discharge (ESD), known for generating shock and plasma, is a promising lab-scale technique for simulating these interactions. Studies with ESD involved placing powders near a spark-producing gap between electrodes and observing mechanical and chemical processes like particle motion and ignition. A limited range of spark conditions and material properties have been tested, which facilitated the development and validation of preliminary computational models describing this system. Significant gaps …


A Molecular Dynamics Study On The Destruction Mechanism Of Per And Polyfluoroalkyl Substances Due To Ultrasound Technology, Bruno Bezerra De Souza May 2024

A Molecular Dynamics Study On The Destruction Mechanism Of Per And Polyfluoroalkyl Substances Due To Ultrasound Technology, Bruno Bezerra De Souza

Dissertations

Per- and polyfluoroalkyl substances (PFAS) are a group of stable synthetic chemicals that are highly persistent and harmful pollutants to the environment and human health. PFAS have caused a strong public and regulatory response due to their ubiquitous presence in the environment and toxicity to humans. The application of ultrasound is one of the most effective treatment technologies for the mineralization of PFAS in contaminated water. However, this technology is treated as a black box causing the inability to be optimized. Therefore, there is a pressing need to investigate the intricate dynamics of PFAS degradation under ultrasound to unlock its …


Targeted Drug Delivery: Investigating Protein Corona Behavior, Atharva Markale May 2024

Targeted Drug Delivery: Investigating Protein Corona Behavior, Atharva Markale

Theses

Due to high specificity and less toxicity, nanoparticles have become promising for targeted drug delivery against cancer, although they face challenges when they enter the bloodstream, making their behavior unpredictable. The deposition of proteins on nanoparticles, the protein corona, changes their biosignature, affecting their circulation, drug release potency, targeting ability, and immunogenicity. The continuous exchange of protein layers on a nanoscale is complex to analyze.

Nanoparticle tracking analysis (NTA) is a method to characterize nanoparticles in blood plasma by combining principles of light scattering microscopy and Brownian motion. In this work, time-dependent experiments with plasma were conducted to analyze the …


Strawberry Nectar Preservation Through Innovative Techniques And Energy Evaluation For High-Pressure Processing, Caterina Scaioli May 2024

Strawberry Nectar Preservation Through Innovative Techniques And Energy Evaluation For High-Pressure Processing, Caterina Scaioli

Theses

Strawberries are universally adored by people of all ages, owing to their richness in vitamins, nutrients, and antioxidants, offering myriad health benefits, including combating free radicals. However, despite their popularity, strawberry juices or nectars are not commonly found in markets due to their delicate structure, which makes them prone to rapid deterioration of their prized qualities and vibrant red color. In the food industry, preventing browning and nutrient deterioration are often the primary challenges faced when processing red juices. Traditional preservation methods, such as pasteurization, are inadequate in maintaining their freshness. The focus of this study is to explore alternative …


Methodology For Developing Biodegradable Polymer Blends And Composites For Agriculture, Fangzhong Xing May 2024

Methodology For Developing Biodegradable Polymer Blends And Composites For Agriculture, Fangzhong Xing

Theses

The use of polyethylene (PE) films to improve soil conditions and to increase crop yield has produced microplastics that are harmful to our ecosystem. The overall objective of this thesis is to develop an effective biodegradable polymer/composite to replace PE, and hence, to reduce microplastic pollution. The focus of this research is to develop a systematic protocol for assessing the suitability of the biodegradable films based on industry standards in agriculture. For this purpose, a range of biodegradable polymer blends are prepared using polylactic acid (PLA) and polybutylene adipate-co-terephthalate (PBAT) with varying PLA to PBAT ratios. Solvent casting combined with …


Utilization Of Iron Fillings Solid Waste For Optimum Biodiesel Production, Fady Ihab Bayoumy Eng., Ahmed Osman Ahmed Dr., David W. Rooney Dr., Mai H. Roushdy May 2024

Utilization Of Iron Fillings Solid Waste For Optimum Biodiesel Production, Fady Ihab Bayoumy Eng., Ahmed Osman Ahmed Dr., David W. Rooney Dr., Mai H. Roushdy

Chemical Engineering

This study explores the innovative application of iron filings solid waste, a byproduct from mechanical workshops, as a heterogeneous catalyst in the production of biodiesel from waste cooking oil. Focusing on sustainability and waste valorization, the research presents a dual-benefit approach: addressing the environmental issue of solid waste disposal while contributing to the renewable energy sector. Particle size distribution analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray fluorescence (XRF), Thermal analysis (TG-DTA), and FTIR analysis were used to characterize the iron filings. The response surface methodology (RSM) was used to guide a series of experiments that were conducted to …


Investigating The Relationship Between Hypoxia, Hypoxia-Inducible Factor 1, And The Optical Redox Ratio In Response To Radiation Therapy, Jesse D. Ivers, Nagavenkatasai Puvvada, Charles M. Quick, Narasimhan Rajaram May 2024

Investigating The Relationship Between Hypoxia, Hypoxia-Inducible Factor 1, And The Optical Redox Ratio In Response To Radiation Therapy, Jesse D. Ivers, Nagavenkatasai Puvvada, Charles M. Quick, Narasimhan Rajaram

Biomedical Engineering Faculty Publications and Presentations

Significance

Radiation resistance is a major contributor to cancer treatment failure and is likely driven by multiple pathways. Multivariate visualization that preserves the spatial co-localization of factors could aid in understanding mechanisms of resistance and identifying biomarkers of response.

Aim

We aim to investigate the spatial and temporal relationship between hypoxia, hypoxia-inducible factor 1 (HIF-1α), and metabolism in response to radiation therapy in two cell lines of known radiation resistance and sensitivity.

Approach

Two-photon excited fluorescence and fluorescence lifetime imaging microscopy were used to quantify the optical redox ratio (ORR) and NAD(P)H fluorescent lifetime and bound fraction in frozen tumor …


Passive Mechanical Properties Of Cardiac And Arterial Tissue: A Paired Comparison Study In A Calf Model, Ola Alsaadi, Jieyang Zhang, Masod Sadipour, Ali N. Azadani May 2024

Passive Mechanical Properties Of Cardiac And Arterial Tissue: A Paired Comparison Study In A Calf Model, Ola Alsaadi, Jieyang Zhang, Masod Sadipour, Ali N. Azadani

DU Undergraduate Research Journal Archive

Purpose: The mechanical behavior of heart tissue plays a crucial role in elucidating cardiac physiology and pathophysiology. Accurate measurement of the mechanical properties of cardiac and arterial tissues is indispensable for advancing computer simulations and developing medical devices. This study aimed to assess the passive mechanical properties of cardiac and arterial tissue in a calf model using a paired comparison method.

Methods: A planar biaxial stretching device was used to determine the mechanical characteristics of 84 square specimens obtained from 14 different anatomical regions. Cauchy stress-Green strain curves were constructed for each anatomical area, and a Fung-type constitutive …


Impact Of Student Beliefs And Self-Efficacy On Performance In Higher Education Stem Courses, Lauren Nicole Fogg May 2024

Impact Of Student Beliefs And Self-Efficacy On Performance In Higher Education Stem Courses, Lauren Nicole Fogg

Doctoral Dissertations

In engineering education, students often face feelings of inadequacy, leading to academic struggles and potential dropout. This dissertation investigates the impact of interactive course materials on students' confidence and self-efficacy in problem-solving, focusing on an Engineering Materials class at Louisiana Tech University. Over four quarters, involving seven sections and 218 students, a 13-question Likert scale survey was administered repeatedly, alongside demographic data and textbook usage surveys. The study aims to compare students’ attitudes and beliefs when not using a textbook versus when using an interactive web-native book. Hypotheses suggest that the interactive book will enhance problem-solving beliefs, confidence, and grades. …


Two Heads Are Better Than One: Single Pilot Operation Threatens The Safety Of The Friendly Skies, Alexandria E. Rook May 2024

Two Heads Are Better Than One: Single Pilot Operation Threatens The Safety Of The Friendly Skies, Alexandria E. Rook

Arkansas Law Review

Boeing’s Maneuvering Characteristics Augmentation System (“MCAS”), an automated piloting system, is only supposed to handle aircraft operations in very specific circumstances. Despite devasting results with MCAS, Boeing has another automated piloting system on the horizon that poses even more grave risks: Single Pilot Operation (“SPO”). Boeing—along with Airbus—wants to replace one of the pilots in the cockpit of commercial airline flights with the new SPO technology it is developing. The FAA should not allow SPO technology to be implemented because it is premature, motivated by financial gain to the detriment of safety, and ignores the importance of professional judgment in …


A Computational Investigation Of Wood Selection For Acoustic Guitar, Jonah Osterhus May 2024

A Computational Investigation Of Wood Selection For Acoustic Guitar, Jonah Osterhus

Senior Honors Theses

The acoustic guitar is a stringed instrument, often made of wood, that transduces vibrational energy of steel strings into coupled vibrations of the wood and acoustic pressure waves in the air. Variations in wood selection and instrument geometry have been shown to affect the timbre of the acoustic guitar. Computational methods were utilized to investigate the impact of material properties on acoustic performance. Sitka spruce was deemed the most suitable wood for guitar soundboards due to its acoustic characteristics, strength, and uniform aesthetic. Mahogany was deemed to be the best wood for the back and sides of the guitar body …


The 2019 Raikoke Eruption As A Testbed Used By The Volcano Response Group For Rapid Assessment Of Volcanic Atmospheric Impacts, Jean Paul Vernier, Thomas J. Aubry, Claudia Timmreck, Anja Schmidt, Lieven Clarisse, Fred Prata, Nicolas Theys, Andrew T. Prata, Graham Mann, Hyundeok Choi, Simon Carn, Richard Rigby, Susan C. Loughlin, John A. Stevenson May 2024

The 2019 Raikoke Eruption As A Testbed Used By The Volcano Response Group For Rapid Assessment Of Volcanic Atmospheric Impacts, Jean Paul Vernier, Thomas J. Aubry, Claudia Timmreck, Anja Schmidt, Lieven Clarisse, Fred Prata, Nicolas Theys, Andrew T. Prata, Graham Mann, Hyundeok Choi, Simon Carn, Richard Rigby, Susan C. Loughlin, John A. Stevenson

Michigan Tech Publications

The 21 June 2019 Raikoke eruption (48°N, 153°E) generated one of the largest amounts of sulfur emission to the stratosphere since the 1991 Mt. Pinatubo eruption. Satellite measurements indicate a consensus best estimate of 1.5Tg for the sulfur dioxide (SO2) injected at an altitude of around 14-15km. The peak Northern Hemisphere (NH) mean 525gnm stratospheric aerosol optical depth (SAOD) increased to 0.025, a factor of 3 higher than background levels. The Volcano Response (VolRes) initiative provided a platform for the community to share information about this eruption which significantly enhanced coordination efforts in the days after the eruption. A multi-platform …


Structural Fiber Mesh Reinforcement Of A Polymeric Heart Valve: Improving Valve Durability And Leaflet Closure Effectiveness, Peter J. Choi, Hugo Zazueta, John A. Acevedo, Philip Park May 2024

Structural Fiber Mesh Reinforcement Of A Polymeric Heart Valve: Improving Valve Durability And Leaflet Closure Effectiveness, Peter J. Choi, Hugo Zazueta, John A. Acevedo, Philip Park

Civil Engineering Faculty Publications

Objective: Bioprosthetic valves using either porcine or bovine pericardium have been widely used for transcatheter heart valve replacements. However, producing bioprosthetic valves is not a sustainable solution. Acquiring animal tissue is often not readily available and costly and requires time-consuming modifications. Moreover, its primary tissue failure requires reoperation after roughly 15 years. The suggested replacement of porcine and bovine leaflets with biocompatible polymers appears to be an attractive alternative to bioprosthetic valves. In this study, engineered fiber-reinforced polymers were developed, which are less degenerative and offer greater hemocompatibility in relation to mechanical valves.
Methods: Polydimethylsiloxane (PDMS) polymer reduces calcification significantly …