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Extended Time, Elevated Expectations: The Unappreciated Downsides Of Pausing The Tenure Clock, Maria A. Holland, Katharina Maisel, Carolyn B. Ibberson, Laura K. Wiley, David C. Burnett, Emily M. Mace, Mary Williard Elting Aug 2024

Extended Time, Elevated Expectations: The Unappreciated Downsides Of Pausing The Tenure Clock, Maria A. Holland, Katharina Maisel, Carolyn B. Ibberson, Laura K. Wiley, David C. Burnett, Emily M. Mace, Mary Williard Elting

Electrical and Computer Engineering Faculty Publications and Presentations

In 1971, Stanford became the first university to introduce tenure clock extensions in academia for new mothers. The American Association of University Professors (AAUP) began recommending such policies a few years later, and in 2001, modified their recommendation to include primary or coequal caregivers, following either the birth or adoption of a child (1). By 2004, 43% of 255 surveyed institutions had formal clock-stop policies...


Supportive-Leadership Training To Improve Social Connection: A Cluster-Randomized Trial Demonstrating Efficacy In A High-Risk Occupational Context, Cynthia Mohr, Leslie Hammer, Jennifer Dimoff, Shalene Allen, James Lee, Sarah Arpin, Sheila Mccabe, Krista Brockwood, Todd Bodner, Luke Mahoney, Multiple Additional Authors Aug 2024

Supportive-Leadership Training To Improve Social Connection: A Cluster-Randomized Trial Demonstrating Efficacy In A High-Risk Occupational Context, Cynthia Mohr, Leslie Hammer, Jennifer Dimoff, Shalene Allen, James Lee, Sarah Arpin, Sheila Mccabe, Krista Brockwood, Todd Bodner, Luke Mahoney, Multiple Additional Authors

Psychology Faculty Publications and Presentations

The high, and rate of loneliness is a threat to public health (Office of the Surgeon General, 2023), with negative mental and physical health consequences (e.g., Holt-Lunstad, 2021). Given that loneliness is a risk factor for poor mental health, efforts to address loneliness are urgently needed. Workplaces can facilitate an employee's social connection through supervisor support training, which can help mitigate loneliness. Among occupational groups, the military is at higher risk for mental health disorders, suicide, and loneliness (Fikretoglu et al., 2022; Naifeh et al., 2019). This study evaluated the efficacy of an evidence-based supportive-leadership training intervention targeting active-duty U.S. …


Ronald E. Mcnair Scholars Program Profiles And Abstracts 2024, Mcnair Scholars Program Aug 2024

Ronald E. Mcnair Scholars Program Profiles And Abstracts 2024, Mcnair Scholars Program

McNair Symposium

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


A Pwm Control Method For Reducing Electromagnetic Noise At The Generation Source In Power Electronic Converters, Abhijeet Prem Aug 2024

A Pwm Control Method For Reducing Electromagnetic Noise At The Generation Source In Power Electronic Converters, Abhijeet Prem

Dissertations and Theses

Advancements in power semiconductor devices are enabling the design of better electrical power conversion systems. Wide Bandgap (WBG) switching devices using materials like Silicon Carbide and Gallium Nitride can operate at higher temperatures, voltages, and frequencies with faster turn-on/off periods, improving converter performance over silicon devices. However, WBG technologies are still new, and the rapid switching transitions of these devices lead to issues such as voltage overshoots, ringing, and electromagnetic interference, which need to be addressed for widespread adoption. This work introduces a new control method for reshaping the switching voltages, which overcomes the disadvantages of fast transition time without …


Layered Naba2m3q3(Q2) (M = Cu Or Ag; Q = S Or Se) Chalcogenides And Local Ordering In Their Mixed-Anion Compositions, Ayat Tassanov, Huiju Lee, Yi Xia, James M. Hodges Aug 2024

Layered Naba2m3q3(Q2) (M = Cu Or Ag; Q = S Or Se) Chalcogenides And Local Ordering In Their Mixed-Anion Compositions, Ayat Tassanov, Huiju Lee, Yi Xia, James M. Hodges

Mechanical and Materials Engineering Faculty Publications and Presentations

Three new NaBa2M3Q3(Q2) (M = Ag or Cu; Q = S or Se) chalcogenides were prepared by using solid-state methods and structurally characterized by using single-crystal X-ray diffraction. NaBa2Ag3Se3(Se2) and NaBa2Cu3Se3(Se2) crystallize in monoclinic space group C2/m and have a two-dimensional structure composed of edge-sharing MSe4/4 tetrahedra separated by Na+ and Ba2+ cations, along with (Se2)2– dimers at the center of the spacings between [M3Se3]3– slabs. NaBa2Ag3S3(S2) adopts a related structure with space group C2/m but has additional, crystallographically distinct Ag atoms in the [Ag3S3]3– layer that are linearly coordinated. NaBa2Ag3Se3(Se2) and NaBa2Ag3S3(S2) have indirect band gaps measured to be …


Agnotology Of The E-Cigarette Industry: How The E-Cigarette Industry Continues The Tobacco Industry's Legacy Of Creating Controversy And Confusion Within The Scientific Community And The General Population, Calvin Lewis Aug 2024

Agnotology Of The E-Cigarette Industry: How The E-Cigarette Industry Continues The Tobacco Industry's Legacy Of Creating Controversy And Confusion Within The Scientific Community And The General Population, Calvin Lewis

University Honors Theses

The purpose of this paper is to determine the extent to which the e-cigarette industry follows in the footsteps of the tobacco industry's attempts to disrupt science and cause controversy. Four tactics are described that the tobacco industry uses to disrupt science: funding research that is designed to show results that support their position, criticizing and suppressing research that goes against their position, changing risk assessment and scientific research standards to fit their aims, and spreading data created by their interest groups to politicians and the nonacademic press. Evidence is found to show that both the tobacco industry and e-cigarette …


Comparing The Performance Of Different Missing Data Imputation Approaches In Discrete Outcome Modeling, Md Istiak Jahan, Tanmoy Bhowmik, Lauren Hoover, Naveen Eluru Aug 2024

Comparing The Performance Of Different Missing Data Imputation Approaches In Discrete Outcome Modeling, Md Istiak Jahan, Tanmoy Bhowmik, Lauren Hoover, Naveen Eluru

Civil and Environmental Engineering Faculty Publications and Presentations

Although several approaches exist for data imputation, these approaches are not commonly applied in transportation. The current paper is geared toward assisting transportation researchers and practitioners in developing models using datasets with missing data. The study begins with a data simulation exercise evaluating different solutions implemented for missing data. The dimensions considered in our analysis include: the nature of independent variables, different types of missing variables, different shares of missing values, multiple data sample sizes, and evaluation of single imputation (SI), multiple imputation (MI) and complete case data (CCD) approach. The comparison is conducted by adopting the appropriate inference process …


Participatory Democracy: The Potential For Civic Transformation Understanding Participants' Learning In The Milwaukie Citizens Jury, Amanda Grace Hudson Aug 2024

Participatory Democracy: The Potential For Civic Transformation Understanding Participants' Learning In The Milwaukie Citizens Jury, Amanda Grace Hudson

Dissertations and Theses

Faced with unresponsive government institutions and the limitations of representative democracy, participatory and deliberative democrats have created alternative models for robust democratic participation such as civic juries, civic assemblies and participatory budgeting. Advocates claim that these methods create better citizens and better outcomes and they claim these forums act as a school of democracy. The schools of democracy theory describes participation as a virtuous circle--that doing democracy will make people more democratic. While these processes often produce enthusiastic supporters and encouraging results, there has been very little research to date that attempts to explain how and why people learn and …


Hierarchy Of Exchange-Correlation Functionals In Computing Lattice Thermal Conductivities Of Rocksalt And Zinc-Blende Semiconductors, Jiacheng Wei, Zhonghao Xia, Yi Xia, Jiangang He Aug 2024

Hierarchy Of Exchange-Correlation Functionals In Computing Lattice Thermal Conductivities Of Rocksalt And Zinc-Blende Semiconductors, Jiacheng Wei, Zhonghao Xia, Yi Xia, Jiangang He

Mechanical and Materials Engineering Faculty Publications and Presentations

Lattice thermal conductivity (𝜅L) is a crucial characteristic of crystalline solids with significant implications for thermal management, energy conversion, and thermal barrier coating. The advancement of computational tools based on density functional theory (DFT) has enabled the effective utilization of phonon quasiparticle-based approaches to unravel the underlying physics of various crystalline systems. While the higher order of anharmonicity is commonly used for explaining extraordinary heat transfer behaviors in crystals, the impact of exchange-correlation (XC) functionals in DFT on describing anharmonicity has been largely overlooked. The XC functional is essential for determining the accuracy of DFT in describing interactions among electrons/ions …


Mmwave Tx-Rx Self-Interference Suppression Through A High Impedance Surface Stacked Ebg, Adewale K. Oladeinde, Ehsan Aryafar, Branimir Pejcinovic Aug 2024

Mmwave Tx-Rx Self-Interference Suppression Through A High Impedance Surface Stacked Ebg, Adewale K. Oladeinde, Ehsan Aryafar, Branimir Pejcinovic

Electrical and Computer Engineering Faculty Publications and Presentations

This paper proposes a full-duplex (FD) antenna design with passive self-interference (SI) suppression for the 28 GHz mmWave band. The reduction in SI is achieved through the design of a novel configuration of stacked Electromagnetic Band Gap structures (EBGs), which create a high impedance path to travelling electromagnetic waves between the transmit and receive antenna elements. The EBG is composed of stacked patches on layers 1 and 2 of a four-layer stack-up configuration. We present the design, optimization, and prototyping of unit antenna elements, stacked EBGs, and integration of stacked EBGs with antenna elements. We also evaluate the design through …


Predicting Hurricane Evacuation Behavior Synthesizing Data From Travel Surveys And Social Media, Tanmoy Bhowmik, Naveen Eluru, Samiul Hasan, Aron Culotta, Kamol Chandra Roy Aug 2024

Predicting Hurricane Evacuation Behavior Synthesizing Data From Travel Surveys And Social Media, Tanmoy Bhowmik, Naveen Eluru, Samiul Hasan, Aron Culotta, Kamol Chandra Roy

Civil and Environmental Engineering Faculty Publications and Presentations

Evacuation behavior models estimated using post-disaster surveys are not adequate to predict real-time dynamic population response as a hurricane unfolds. With the emergence of ubiquitous technology and devices in recent times, social media data with its higher spatio-temporal coverage has become a potential alternative for understanding evacuation behaviour during hurricanes. However, these data are often associated with selection bias and population representativeness issues. To that extent, the current study proposes a novel data fusion algorithm to combine heterogeneous data sources from transportation systems and social media, in a unified framework to understand and predict real-time population response during hurricanes. Specifically, …


Organizational Reliability And Resilience As A Dynamic System: Knowledge Modeling With Fuzzy Cognitive Maps, Antonie J. Jetter, Ahmed A. Alibage, Nan Peter Liang Aug 2024

Organizational Reliability And Resilience As A Dynamic System: Knowledge Modeling With Fuzzy Cognitive Maps, Antonie J. Jetter, Ahmed A. Alibage, Nan Peter Liang

Engineering and Technology Management Faculty Publications and Presentations

Safety research in complex environments recommends that high-hazard industries improve reliability and increase their capacity for resilience by enacting principles for high-reliability organizing (HRO). This view has been highly influential in many industries, ranging from aviation to hospitals, and is at the core of many safety culture programs. However, even though HRO principles originated in business practice and were observed in diverse organizations, practitioners frequently struggle to enact them in the contexts of their work. This is likely caused by two limitations of current research: principles are insufficiently specified and the interdependencies between them, such as mutually reinforcing vs. tradeoff …


Smart Grid Cybersecurity In The Age Of Artificial Intelligence, Chip Corbett, Charles M. Weber, Timothy R. Anderson Aug 2024

Smart Grid Cybersecurity In The Age Of Artificial Intelligence, Chip Corbett, Charles M. Weber, Timothy R. Anderson

Engineering and Technology Management Faculty Publications and Presentations

The security of the power grid is essential for the proper function of a democratic society, yet it is constantly under threat. The internet of things (loT) will make a bad situation much worse. Misinformation, disinformation, and malinformation (MDM) have been identified as serious threats to our democratic institutions, and that same acronym applies to mobile device management (MDM), and these devices have become ubiquitous. People are notoriously bad at doing basic cybersecurity. With trillions of devices and remote access everywhere, what could possibly go wrong? Now add in the engaging opportunity of distributed energy resources (DERs) and life gets …


Power Resilience Planning Under The Threat Of Artificial Intelligence, Chip Corbett, Cuong Nguyen, Dahm M. Hongchai, Prajakta Thorat, Pavithra Prasad, Sarah Von Schimmelmann, Charles M. Weber, Timothy R. Anderson Aug 2024

Power Resilience Planning Under The Threat Of Artificial Intelligence, Chip Corbett, Cuong Nguyen, Dahm M. Hongchai, Prajakta Thorat, Pavithra Prasad, Sarah Von Schimmelmann, Charles M. Weber, Timothy R. Anderson

Engineering and Technology Management Faculty Publications and Presentations

The earth is an unstable planet. Change is constant and frequently chaotic. It is very important to plan carefully to manage changes that can be anticipated now, and to cover potential issues that might not yet have been discovered. The dawn of artificial intelligence (AI) presents a host of new concerns and opportunities. The criteria for evaluation are diverse and complex. Cybersecurity is absolutely essential, yet advances in technology have created an internet of things (IoT) where threat vectors might gain access to critical command and control elements through trillions of connected IoT devices. Whereas elegant zero trust cybersecurity models …


Five Pivotal Practices For Leaders To Cultivate Empathy Within Virtual Scrum Teams, Dahm Mongkol Hongchai, Charles M. Weber Aug 2024

Five Pivotal Practices For Leaders To Cultivate Empathy Within Virtual Scrum Teams, Dahm Mongkol Hongchai, Charles M. Weber

Engineering and Technology Management Faculty Publications and Presentations

In the digital and global economy, business leaders need more than just business and technology competencies; they also require empathy. However, there is a notable scarcity of research on empathy in Scrum for product development. This study aims to uncover critical insights into how leaders can foster empathy within virtual Scrum teams. Accordingly, this paper proposes five pivotal themes leaders can employ: Scrum fundamentals, meditation, self- and other-analysis, healthy interactions, and informal connections. These vital strategies offer actionable methods for leaders seeking to enhance empathy within their virtual Scrum teams.


Improving Attendance To Achieve Organizational Goals: A Case Study Of Human-Centered Design In A Small Us Plant-Based Food Manufacturer, Angel Contreras-Cruz, Eduardo Ahumada-Tello Aug 2024

Improving Attendance To Achieve Organizational Goals: A Case Study Of Human-Centered Design In A Small Us Plant-Based Food Manufacturer, Angel Contreras-Cruz, Eduardo Ahumada-Tello

Engineering and Technology Management Faculty Publications and Presentations

Plant-based food manufacturing companies face high staff turnover rates and attendance problems. It is challenging for those companies to maintain an acceptance level of employee retention and attendance to achieve their objectives. Companies rely on front-line employees to meet production plans, but employees who do not show up at work jeopardize companies' operations. Additional challenges, such as retaining and attracting talent after the COVID-19 pandemic, are present daily for several U.S. organizations. This study analyzes attendance data from the case study company to design an attendance policy. Attendance data suggested that nearly 60 percent of the operational workforce had attendance …


Mental Models Of Translational Scientists, Rasnia Tabpla, Antonie J. Jetter Aug 2024

Mental Models Of Translational Scientists, Rasnia Tabpla, Antonie J. Jetter

Engineering and Technology Management Faculty Publications and Presentations

Translational science aims to bridge the gap between scientific discoveries and practical application yet faces challenges in achieving high success rates. This study examines the effective engagement of translational scientists, who play a key role in the translation process. It uses Fuzzy Cognitive Maps (FCMs) to analyze the scientists' mental models and identify common concepts related to success factors, such as ability, resources, opportunity, and entrepreneurial competencies. It then compares the mental models of the scientists and finds that mental models exhibit similarities, yet variations exist such as density and connectedness. Scenario analysis with FCM is then used to identify …


Technology Convergence And Its Influence On Innovation Networks: An Assessment Of Emerging Trends, Shuying Li, Wudan Ma, Xiaoyu Wang, Xian Zhang, Haiyun Xu, Edwin Garces, Tugrul U. Daim Aug 2024

Technology Convergence And Its Influence On Innovation Networks: An Assessment Of Emerging Trends, Shuying Li, Wudan Ma, Xiaoyu Wang, Xian Zhang, Haiyun Xu, Edwin Garces, Tugrul U. Daim

Engineering and Technology Management Faculty Publications and Presentations

AI-age technologies will evolve at an accelerated pace, driven by long-term mutually beneficial symbiosis. Technology convergence will disrupt existing industrial technology fields in general. Assessing and predicting technology convergence will become an important technology management issue in the AI era, providing new clues for distinguishing key technologies in innovation. Existing analytical models prefer to detect retrospective convergence. The role of emerging converging technologies in developing new technologies, generating new applications, and facilitating collaboration and commercialization across different phases is not well understood. In this paper, we build a technology co-occurrence network from the perspective of technology evolution and community detection, …


Strengthening Capacity In Industrial Revolution 4.0 (Ir 4.0): A Case Study On Training Product-Service Systems Between The Us And Vietnam, Man Hang Yip, Ana Sofia Castellanos Santarnaria, Julia J. Babcock Aug 2024

Strengthening Capacity In Industrial Revolution 4.0 (Ir 4.0): A Case Study On Training Product-Service Systems Between The Us And Vietnam, Man Hang Yip, Ana Sofia Castellanos Santarnaria, Julia J. Babcock

Engineering and Technology Management Faculty Publications and Presentations

This case study analyzes how value is created in the development process of a collaborative training product-service system (PSS) designed for provincial government officials in Vietnam. This initiative, part of the USAID Strengthening Provincial Capacity (USAID SPC) project, encapsulates a series of training solutions designed to empower officials with key skills in engineering and technology management, including the knowledge to improve global value chains, upgrade technology infrastructure and sustainable production models. A primary driver for the “four-day course delivery”, the PSS analyzed in this study, was to bolster economic competitiveness at the provincial level in the context of Industrial Revolution …


Wired For Success: A Neurobiological Approach To Improving The Academic Outcomes Of Middle School Boys, Allison Emery Aug 2024

Wired For Success: A Neurobiological Approach To Improving The Academic Outcomes Of Middle School Boys, Allison Emery

University Honors Theses

Male accomplishment in scholastic settings has been declining globally for the last decade, leading to long-term consequences for boys and men. Possible neurobiological underpinnings of the gender gap in education are discussed in this literature review. While male and female differences have, in the past, largely been considered socialized, recent science also confirms neurobiological variances between male and female development. These distinctions are assessed for their potential ties to the decline in male academic success, and are correlated to classroom practices, strategies and interventions meant to increase boys' engagement and performance.


Climate And Extreme Weather Event Impacts On Administrators, Direct Care Staff, And Residents In Oregon Assisted Living, Residential Care, And Memory Care Communities, 2024, Dani Himes, Jacklyn Kohon, Madeline Fox, Laura Rodriguez, Sarah Dys, Diana Jacoby, Paula Carder Aug 2024

Climate And Extreme Weather Event Impacts On Administrators, Direct Care Staff, And Residents In Oregon Assisted Living, Residential Care, And Memory Care Communities, 2024, Dani Himes, Jacklyn Kohon, Madeline Fox, Laura Rodriguez, Sarah Dys, Diana Jacoby, Paula Carder

Institute on Aging Publications

This brief report on AL/RC staff and resident experiences with climate events highlights the voices of AL/RC direct care staff, former direct care staff, residents, administrators, and management representatives to promote well-being in these care settings. This study can inform Oregon’s efforts to support long-term care workforce readiness for future climate emergencies and inform future quantitative data collection on AL/RC and other long-term care workers, including those employed in home health agencies, nursing facilities, and adult foster homes.


Quantifying Relationships In Fuzzy Cognitive Maps Based On Content Analysis Of Unstructured Research Texts, Ahmed Alibage, Antonie J. Jetter, Elpiniki Papageorgiou Aug 2024

Quantifying Relationships In Fuzzy Cognitive Maps Based On Content Analysis Of Unstructured Research Texts, Ahmed Alibage, Antonie J. Jetter, Elpiniki Papageorgiou

Engineering and Technology Management Faculty Publications and Presentations

FCM projects often rely on knowledge-based approaches, such as expert interviews, which can be challenging to conduct because they require extensive expert participation. We propose a novel alternative to create FCM models based on expert knowledge that is already codified in research texts and other publications. In this approach, thematic network analysis identifies FCM concepts and signed causal connections, while computation of t-coefficient is used to determine the weights of the identified edges. We introduce and evaluate the approach in the context of a real-world system modeling project that is based on 47 carefully selected, peer reviewed research publications on …


Story Of Your Lazy Function’S Life: A Bidirectional Demand Semantics For Mechanized Cost Analysis Of Lazy Programs, Liyao Xia, Laura Israel, Maite Kramarz, Stephanie Weirich, Koen Claessen, Nicolas Coltharp, Yao Li Aug 2024

Story Of Your Lazy Function’S Life: A Bidirectional Demand Semantics For Mechanized Cost Analysis Of Lazy Programs, Liyao Xia, Laura Israel, Maite Kramarz, Stephanie Weirich, Koen Claessen, Nicolas Coltharp, Yao Li

Computer Science Faculty Publications and Presentations

Lazy evaluation is a powerful tool that enables better compositionality and potentially better performance in functional programming, but it is challenging to analyze its computation cost. Existing works either require manually annotating sharing, or rely on separation logic to reason about heaps of mutable cells. In this paper, we propose a bidirectional demand semantics that allows for extrinsic reasoning about the computation cost of lazy programs without relying on special program logics. To show the effectiveness of our approach, we apply the demand semantics to a variety of case studies including insertion sort, selection sort, Okasaki's banker's queue, and the …


Story Of Your Lazy Function's Life: A Bidirectional Demand Semantics For Mechanized Cost Analysis Of Lazy Programs, Li-Yao Xia, Laura Israel, Maite Kramarz, Nicholas Coltharp, Koen Claessen, Stephanie Weirich, Yao Li Aug 2024

Story Of Your Lazy Function's Life: A Bidirectional Demand Semantics For Mechanized Cost Analysis Of Lazy Programs, Li-Yao Xia, Laura Israel, Maite Kramarz, Nicholas Coltharp, Koen Claessen, Stephanie Weirich, Yao Li

Computer Science Faculty Publications and Presentations

Lazy evaluation is a powerful tool that enables better compositionality and potentially better performance in functional programming, but it is challenging to analyze its computation cost. Existing works either require manually annotating sharing, or rely on separation logic to reason about heaps of mutable cells. In this paper, we propose a bidirectional demand semantics that allows for extrinsic reasoning about the computation cost of lazy programs without relying on special program logics. To show the effectiveness of our approach, we apply the demand semantics to a variety of case studies including insertion sort, selection sort, Okasaki's banker's queue, and the …


Improving Biomimetic Passive Dynamics Of A Quadruped Robot Hind Leg Hip Joint With A 3d Printed Torsion Spring, Haonan Zheng Jul 2024

Improving Biomimetic Passive Dynamics Of A Quadruped Robot Hind Leg Hip Joint With A 3d Printed Torsion Spring, Haonan Zheng

Dissertations and Theses

The Agile and Adaptive Robotics Lab is interested in researching the neuromuscular control network of legged animal locomotion. To validate the lab's understanding of biological neural control, synthetic neural networks are developed and applied to biologically inspired legged robots. For a synthetic neural network to operate in the same manner as a biological neural network and produce the same locomotor behavior, the robot that the synthetic neural network is controlling must also mimic its biological counterpart. Previous research produced a quadruped robot hind leg designed with biomimetic passive dynamics by installing spring and damper pairs at each joint, however, an …


Enhancement Of Mechanical Properties Of Pcl/Pla/Dmso2 Composites For Bone Tissue Engineering, Kyung-Eun Min, Jae-Won Jang, Cheolhee Kim, Sung Yi Jul 2024

Enhancement Of Mechanical Properties Of Pcl/Pla/Dmso2 Composites For Bone Tissue Engineering, Kyung-Eun Min, Jae-Won Jang, Cheolhee Kim, Sung Yi

Mechanical and Materials Engineering Faculty Publications and Presentations

Bone tissue engineering shows potential for regenerating or replacing damaged bone tissues by utilizing biomaterials renowned for their biocompatibility and structural support capabilities. Among these biomaterials, polycaprolactone (PCL) and polylactic acid (PLA) have gained attention due to their biodegradability and versatile applications. However, challenges such as low degradation rates and poor mechanical properties limit their effectiveness. Dimethyl sulfone (DMSO2) has emerged as a potential additive to address these limitations, offering benefits such as reduced viscosity, increased degradation time, and enhanced surface tension. In this study, we investigate tailored composites comprising PLA, PCL, and DMSO2 to enhance mechanical …


Ultrasonic Cigarettes: Chemicals And Cytotoxicity Are Similar To Heated-Coil Pod-Style Electronic Cigarettes., Esther E. Omaiye, Wentai Luo, Kevin J. Mcwhirter, Prue Talbot Jul 2024

Ultrasonic Cigarettes: Chemicals And Cytotoxicity Are Similar To Heated-Coil Pod-Style Electronic Cigarettes., Esther E. Omaiye, Wentai Luo, Kevin J. Mcwhirter, Prue Talbot

Civil and Environmental Engineering Faculty Publications and Presentations

Our purpose was to test the hypothesis that ultrasonic cigarettes (u-cigarettes), which operate at relatively low temperatures, produce aerosols that are less harmful than heated-coil pod-style electronic cigarettes (e-cigarettes). The major chemicals in SURGE u-cigarette fluids and aerosols were quantified, their cytotoxicity and cellular effects were assessed, and a Margin of Exposure risk assessment was performed on chemicals in SURGE fluids. Four SURGE u-cigarette flavor variants ("Blueberry Ice," "Watermelon Ice," "Green Mint," and "Polar Mint") were evaluated. Flavor chemicals were quantified in fluids and aerosols using gas chromatography/mass spectrometry. Cytotoxicity and cell dynamics were assessed using the MTT assay, live-cell …


Examining Driver Injury Severity In Motor Vehicle Crashes: A Copula-Based Approach Considering Temporal Heterogeneity In A Developing Country Context, Shahrior Pervaz, Tanmoy Bhowmik, Naveen Eluru Jul 2024

Examining Driver Injury Severity In Motor Vehicle Crashes: A Copula-Based Approach Considering Temporal Heterogeneity In A Developing Country Context, Shahrior Pervaz, Tanmoy Bhowmik, Naveen Eluru

Civil and Environmental Engineering Faculty Publications and Presentations

Using data from a developing country, the current study develops a copula-based joint modeling framework to study crash type and driver injury severity as two dimensions of the severity process. To be specific, a copula-based multinomial logit model (for crash type) and generalized ordered logit model (for driver severity) is estimated in the study. The data for our analysis is drawn from Bangladesh for the years of 2000 to 2015. Given the presence of multiple years of data, we develop a novel spline variable generation approach that facilitates easy testing of variation in parameters across time in crash type and …


Toxicity Of Waterpipe Tobacco Smoking: The Role Of Flavors, Sweeteners, Humectants, And Charcoal, Nada O F Kassem, Robert M. Strongin, Andrea M. Stroup, Marielle C. Brinkman, Ahmad El-Hellani, Hanno C. Erythropel, Arash Etemadi, Maciej L. Goniewicz, Eleanore G. Hansen, Noura O. Kassem, Multiple Additional Authors Jul 2024

Toxicity Of Waterpipe Tobacco Smoking: The Role Of Flavors, Sweeteners, Humectants, And Charcoal, Nada O F Kassem, Robert M. Strongin, Andrea M. Stroup, Marielle C. Brinkman, Ahmad El-Hellani, Hanno C. Erythropel, Arash Etemadi, Maciej L. Goniewicz, Eleanore G. Hansen, Noura O. Kassem, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

Waterpipe tobacco (WPT) smoking is a public health concern, particularly among youth and young adults. The global spread of WPT use has surged since the introduction of pre-packaged flavored and sweetened WPT, which is widely marketed as a safer tobacco alternative. Besides flavorants and sugars, WPT additives include humectants, which enhance the moisture and sweetness of WPT, act as solvents for flavors, and impart smoothness to the smoke, thus increasing appeal to users. In the United States (U.S.), unlike cigarette tobacco flavoring (with the exception of menthol), there is no FDA product standard or policy in place prohibiting sales of …


Water Throughout The Green Energy Transition: Hydrosocial Dimensions Of Coal, Natural Gas, And Lithium, Joshua J. Cousins, Alida Cantor, Bethani Turley Jul 2024

Water Throughout The Green Energy Transition: Hydrosocial Dimensions Of Coal, Natural Gas, And Lithium, Joshua J. Cousins, Alida Cantor, Bethani Turley

Geography Faculty Publications and Presentations

Energy transitions are reshaping hydrosocial relations. How they will be reshaped, however, depends on location and water's material relationship to other resources and industrial activities embedded within energy transitions. To highlight this, we focus on three different resources—coal, natural gas, and lithium—to signal how the water–energy nexus will be reworked in a transition away from fossil fuels. We examine the water–coal nexus as an example of a resource relationship that is transitioning out, or that is being moved away from in the green energy transition. Natural gas represents the “bridge fuel” used through the transition. Lithium illustrates a resource inside …