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Detection Of The Presence And Growth Of E. Coli Bacteria In A Droplet-Based Microfluidic System Using Laser Induced Fluorescence, Oshira Peiris Apr 2026

Detection Of The Presence And Growth Of E. Coli Bacteria In A Droplet-Based Microfluidic System Using Laser Induced Fluorescence, Oshira Peiris

Theses and Dissertations

Antimicrobial resistance is a biomedical event, wherein an infectious microbe becomes non-responsive to the dosage of a particular antibiotic due to previous overuse or overexposure. Currently, agar plate disc diffusion is used as the gold standard for detecting antimicrobial resistance. The possibility of miniaturizing and speeding up detection techniques for antimicrobial resistance is investigated in this thesis. Microfabrication techniques were used in developing two droplet microfluidic systems interfaced with laser induced fluorescence detection. Microfluidic devices were manufactured with different droplet generating geometries using poly-dimethyl siloxane, soft lithography and hydrophobic surface treatment. The microfluidic devices were tested for droplet quality using …


Model Unification: A Systematic Approach For The Cluster Expansion, Kolten Barfuss Apr 2026

Model Unification: A Systematic Approach For The Cluster Expansion, Kolten Barfuss

Theses and Dissertations

A systematic approach for model unification of cluster expansion models is developed and demonstrated. The method builds on previous work with the Manifold Boundary Approximation Method (MBAM) to identify supremal models. The work is motivated by the exercise of unifying cluster expansion models – characterized by Π matrices – for two binary alloys that share one atomic species to form a model for the ternary alloy. The result is the Supremal Π Algorithm, a systematic unification algorithm that relies on an MBAM-informed understanding of models and on the singular value decomposition. The algorithm yields ΠΛ, a Π matrix for the …


Development And Flight Of Stratospheric Missions For Hard X-Ray Polarimetry And Hard X-Ray Spectroscopy, Ephraim Gau Apr 2026

Development And Flight Of Stratospheric Missions For Hard X-Ray Polarimetry And Hard X-Ray Spectroscopy, Ephraim Gau

Arts & Sciences Graduate Student Theses and Dissertations

The recent launches of the {\it Imaging X-ray Polarimetry Explorer} ({\it IXPE}\,) and {\it XRISM} have provided significant advances to the realms of polarization and high-resolution spectroscopy in X-ray astrophysics. However, both of these satellite missions conduct measurements in the soft X-rays, below 10 keV. To obtain a complete picture of any astrophysical source, we must extend these capabilities to the hard X-rays, above 10 keV, as well. Thus, in my graduate work, I have directed my efforts in these two regimes: measuring the polarization of hard X-rays with {\it XL-Calibur}, and improving the energy resolution of hard X-ray telescopes …


Some Closure On The Relation Between Cfg And Peg, Nathan J. Bulloch Apr 2026

Some Closure On The Relation Between Cfg And Peg, Nathan J. Bulloch

Theses and Dissertations

We work toward a practical, unified language formalism for structurally recursive languages by expressing the mathematical theories underlying context-free grammars with lookahead (CFGLA) in the Rocq theorem prover and leveraging CFGLA semantics to analyze interactions between between recursion and negative lookahead. We give examples of grammars with left-recursive negation cycles for the parsing expression grammar (PEG) variant due to Medeiros et al. and for the translation from PEG to CFGLA due to Miyazaki and Minamide. To study the interaction between left recursion and negative lookahead in a PEG context, we introduce FPEG, a left-recursive extension of PEG with Fitting semantics.


Templating Effect Of Neutral Dithiane Ligands On The Self-Assembly Of Cationic Au(I)-Phosphine Units, Farzane Osanlou, Abdollah Neshat, Mohammad Reza Yousefshahi, Vaclav Eigner, Michal Dusek, Shahram Seidi Apr 2026

Templating Effect Of Neutral Dithiane Ligands On The Self-Assembly Of Cationic Au(I)-Phosphine Units, Farzane Osanlou, Abdollah Neshat, Mohammad Reza Yousefshahi, Vaclav Eigner, Michal Dusek, Shahram Seidi

Turkish Journal of Chemistry

The interactions between the dinuclear Au(I) precursor (dppm)Au2Cl2 and neutral sulfur-containing dithianes (specifically 1,3- and 1,4-dithiane) were examined in the presence of NH₄PF₆. Although these sulfur-based ligands were initially employed to facilitate the formation of mixed phosphine/sulfur Au(I) complexes, single-crystal X-ray diffraction analysis revealed the unexpected generation of multinuclear Au(I) assemblies exclusively coordinated by phosphine ligands. When 1,3-dithiane was present, a trinuclear Au(I) complex was isolated, characterized by a central four-coordinate Au(I) center exhibiting a distorted see-saw geometry, flanked by two terminal Au(I) centers with T-shaped coordination environments. Importantly, the dithiane ligand did not coordinate directly to the gold centers …


Sustainability, Culture, And Higher Education: An Autoethnographic Sustainability Comparison Of The Sustainability Initiatives At The University Of Salzburg And Bowling Green State University, Madison Alt Apr 2026

Sustainability, Culture, And Higher Education: An Autoethnographic Sustainability Comparison Of The Sustainability Initiatives At The University Of Salzburg And Bowling Green State University, Madison Alt

Honors Projects

Human activity is already triggering damaging environmental tipping points (Lenton, 2020), emphasizing the need for sustainability in all aspects of development. Institutes of Higher Education (IHEs) have the power and responsibility to contribute to a more sustainable world (Parr et al., 2022). Bowling Green State University (BGSU) in Ohio, United States, and the Paris Lodron University of Salzburg (PLUS) in Salzburg, Austria are two IHEs with multifaceted sustainability programs. While living and studying at BGSU and PLUS, I used autoethnography, a personal narrative approach, combined with public sustainability information to compare the sustainability initiatives at each university, and determine what …


Exploring Alternate Methods Of Flood Output Estimation During Natural Disasters, Finley Gardner Apr 2026

Exploring Alternate Methods Of Flood Output Estimation During Natural Disasters, Finley Gardner

Honors College Theses

In April of 2025, extreme flooding damaged many homes and buildings of people across Kentucky. The Federal Emergency Management Agency (FEMA) produces maps that show the potential for flooding in areas around water bodies, but many of the April flooding damaged areas were well outside of the FEMA classification zones. The main purpose of this thesis research was to create an accurate model of potential flood extent in Kentucky and compare it to FEMA maps. This model did not require extensive computing power and produced a map that accurately depicted flood extent through the use of Digital Elevation Model (DEM) …


Designing, Integrating, And Evaluating Blockchain Assignments In The Undergraduate Computer Science Program, Karol Lejmbach Apr 2026

Designing, Integrating, And Evaluating Blockchain Assignments In The Undergraduate Computer Science Program, Karol Lejmbach

Dissertations (1934 -)

Blockchains as a technology rely heavily on a wide range of computer science topics. These topics include: algorithms, data structures, network communication, cryptography and many more. These topics align nicely with topics often covered in undergraduate computer science course. Blockchain technology offers an interesting opportunity for computer science educa- tors. Blockchains rely heavily on a wide range of computer science topics. These topics include: cryptography, networking, data structures, and algorithms. Many of these top- ics are explored in undergraduate computer science programs either in core or elective classes. This offers an opportunity for teaching students about emerging technologies, such as …


The Impact Of State And Federal Policies On Academic Researchers: Findings From A National Survey, Dylan Ruediger, Chelsea Mccracken, Jonathan Barefield Apr 2026

The Impact Of State And Federal Policies On Academic Researchers: Findings From A National Survey, Dylan Ruediger, Chelsea Mccracken, Jonathan Barefield

Copyright, Fair Use, Scholarly Communication, etc.

Key findings

● State and federal policies targeting divisive concepts or DEI are shaping research agendas at scale and across disciplines. Twenty percent of all respondents, and 29 percent of researchers working in states with divisive concepts or similar laws, reported having avoided certain research topics because of state laws and policies.

● Eight percent of respondents representing a wide range of disciplines reported having had a federal grant cancelled in 2025.

● Eleven percent of respondents reported that federal and state policies restricting research activities are compelling them to seek employment out of state, to leave the academy, or …


Uptake And Fate Of Silver And Zinc Engineered Nanoparticles In Maize Under Single And Binary Dosing Soil Ecosystems, Lei Xu, Qingbo Yang, Xingmao Ma, Honglan Shi, John Yang, Hu Yang, Samira Mahdi, Ying Wang, Young Shin Jun Apr 2026

Uptake And Fate Of Silver And Zinc Engineered Nanoparticles In Maize Under Single And Binary Dosing Soil Ecosystems, Lei Xu, Qingbo Yang, Xingmao Ma, Honglan Shi, John Yang, Hu Yang, Samira Mahdi, Ying Wang, Young Shin Jun

Chemistry Faculty Research & Creative Works

Recent agricultural applications of engineered metallic nanoparticles (ENPs) have raised concerns about their uptake and fate in plants. To understand this critical issue, this study investigated the fate and uptake of silver (Ag) and zinc oxide (ZnO) ENPs in maize (Zea mays L.) after single or binary ENP exposure in soil. Results indicated that both Zn and Ag elemental concentrations in roots increased with increasing ENP dosage. Ag NPs in the tissues were detected, but not Zn NPs. Ag NP concentration was 3 times higher in the roots than in the shoots at low Ag NP dosing, while Ag NP …


Reading The Room: A Structural Account Of Constraint-Based Processing And Its Limits In Artificial Systems, Griselda Poe Apr 2026

Reading The Room: A Structural Account Of Constraint-Based Processing And Its Limits In Artificial Systems, Griselda Poe

Publications and Research

This paper does not introduce a new structure.

It makes explicit a structural relation implied but not directly stated in prior work.

Human interpersonal processing is grounded in the co-presence of internal constraint and dependency.

These do not exist as separable components.

They form a single structural condition.

This paper shows that what is commonly described as “reading the room” is not a unitary function.

It differs across configurations in how this condition is processed.

In EF configurations, the effect of this condition is expressed through translation into self-return: outputs are evaluated in terms of how they return to the …


Extreme Cf: A Structural Account Of Processing Absence And Category Absence In Cf-Foregrounded Configurations, Griselda Poe Apr 2026

Extreme Cf: A Structural Account Of Processing Absence And Category Absence In Cf-Foregrounded Configurations, Griselda Poe

Publications and Research

Existing frameworks of cognition and intervention assume that processing occurs, meaning is available, and evaluation can be applied.

This paper describes a configuration in which this assumption does not hold.

In CF-foregrounded processing where modulation is absent, processing occurs only when coherence is satisfied. When coherence is not satisfied, processing does not occur. Under this condition, no representation is generated, no evaluation applies, and no action selection is produced.

Within single-layer cognitive models, EF and CF are not distinguished. Within such models, CF does not exist as a condition.

This configuration has not been represented as a category within existing …


A Backend Database Architecture For Persistent Epilepsy Classification Records, Attiksh A. Panda, Deep Desai, Artem Zabarov, Katrina D. Prantzalos, Satya S. Sahoo, Shuai Xu Apr 2026

A Backend Database Architecture For Persistent Epilepsy Classification Records, Attiksh A. Panda, Deep Desai, Artem Zabarov, Katrina D. Prantzalos, Satya S. Sahoo, Shuai Xu

Student Scholarship

Epilepsy affects over five million people globally each year, yet consistent clinical diagnosis remains a persistent challenge due to the lack of standardized classification workflows across medical institutions. The Four-Dimensional Epilepsy Classification (4D-EC) framework, developed by Lüders et al., provides a comprehensive structure for characterizing paroxysmal events across four dimensions: seizure semiology, epileptogenic zone, etiology, and comorbidities. Despite its clinical and educational value, no dedicated informatics platform existed to support its routine use until recently, limiting widespread adoption among clinicians and trainees. This project addresses that gap by implementing a full-stack web application that operationalizes the 4D-EC framework for clinical …


Quantum Simulation And Nanoscale Sensing Of Many-Body Phenomena With Solid-State Spin Defects, Guanghui He Apr 2026

Quantum Simulation And Nanoscale Sensing Of Many-Body Phenomena With Solid-State Spin Defects, Guanghui He

Arts & Sciences Graduate Student Theses and Dissertations

Emergent phenomena in interacting quantum systems arise from collective behavior that cannot be reduced to single-particle physics. Understanding these phenomena requires platforms capable of both synthesizing many-body states under controlled conditions and probing them at the microscopic scale where correlations originate. Solid-state spin defects, including nitrogen-vacancy (NV) centers in diamond and negatively charged boron vacancy centers in hexagonal boron nitride (hBN), offer precisely this dual capability. In the first part of this dissertation, a strongly interacting NV ensemble is subjected to periodic and quasi-periodic drives to access a long-lived prethermal regime and realize a discrete time quasicrystal (DTQC). In the …


Asymptotic Sensitivity And Adjoint Methods For Equation Discovery With Open-Source Implementation, Nathan Schill Apr 2026

Asymptotic Sensitivity And Adjoint Methods For Equation Discovery With Open-Source Implementation, Nathan Schill

Theses and Dissertations

The "on-the-fly" (OTF) method is a gradient-based approach to equation discovery. It makes use of (potentially limited) observational data, a data assimilation technique such as continuous data assimilation (also called nudging), and an error metric. From these it computes an asymptotic approximation of a simulated system's error sensitivity with respect to unknown parameters and utilizes any gradient-based optimization algorithm to perform parameter updates. These parameter updates may be done online or offline, and the model may be of a precisely specified form or simply a library of possible terms with potentially nonlinear parameters. We have applied the adjoint method to …


Sonic Booms From Rockets: Measurements And Modeling, Mark Charles Anderson Apr 2026

Sonic Booms From Rockets: Measurements And Modeling, Mark Charles Anderson

Theses and Dissertations

Rocket sonic booms are produced when launch vehicles or boosters travel faster than the local speed of sound in the atmosphere, generating systems of conical shock waves. The purpose of this dissertation is to perform high-fidelity measurements of rocket sonic booms and to explain the physics behind the unique phenomena observed. After a thorough literature review on sonic booms produced during spaceflight operations, Part I of this dissertation deals with measurement and analysis challenges. One challenge is reducing contaminating noise effects on sonic boom perception metrics, addressed using a low-pass filtering method tied to the noise floor. A second challenge …


Characterizing The Unique Chemical Imprint Of On-Axis, Lower-Temperature Hydrothermal Flow To The Deep Ocean (Southern East Pacific Rise, 16.5°–18.0°S), Laura E. Moore, Randelle M. Bundy, Joseph A. Resing, Scott M. White, Tamara Baumberger, Peter N. Sedwick, Nathaniel J. Buck, Anson M. Antriasian, Isaac Keohane Apr 2026

Characterizing The Unique Chemical Imprint Of On-Axis, Lower-Temperature Hydrothermal Flow To The Deep Ocean (Southern East Pacific Rise, 16.5°–18.0°S), Laura E. Moore, Randelle M. Bundy, Joseph A. Resing, Scott M. White, Tamara Baumberger, Peter N. Sedwick, Nathaniel J. Buck, Anson M. Antriasian, Isaac Keohane

Faculty Publications

In addition to high-temperature vents, lower-temperature flow (LTF) (< 300°C) is abundant along mid-ocean ridges and contributes globally-important fluxes of heat and water along with largely-unconstrained geochemical influences on the ocean. We examined the impact of on-axis LTF on the chemical composition of the overlying water column (< 40 m above seafloor) along the 16.5°–18.0°S sector of the ultrafast-spreading southern East Pacific Rise using autonomous underwater vehicle Sentry surveys and conductivity-temperature-depth rosette casts. LTF sites were typically spatially isolated from high-temperature systems and imparted unique chemical signatures to the overlying ocean. Water column samples impacted by LTF exhibited low particulate iron:sulfur ratios and high methane: total-dissolvable manganese ratios, whereas samples influenced by high-temperature venting exhibited opposite trends. We confirmed that LTF imparts a distinct and measurable chemical signature to the water column, independent from high-temperature vents. Isolated, on-axis LTF will be important to consider when assessing hydrothermal circulation impacts upon ocean biogeochemistry.


Real And Perceived Barriers To Effective Use Of Cataract Surgical Supplies, Caitlin Davie, Lindsay K. Cloud, Scott Burris, Shaina Shiwdin, Brooke Sherry, Christina R. Prescott, Joel Schuman, David Palmer, David Chang, Daniel Parra, Cordelia Kwon, Margaret A. Tharp, Cassandra L. Thiel Apr 2026

Real And Perceived Barriers To Effective Use Of Cataract Surgical Supplies, Caitlin Davie, Lindsay K. Cloud, Scott Burris, Shaina Shiwdin, Brooke Sherry, Christina R. Prescott, Joel Schuman, David Palmer, David Chang, Daniel Parra, Cordelia Kwon, Margaret A. Tharp, Cassandra L. Thiel

Wills Eye Hospital Papers

INTRODUCTION: Cataract surgery, among the most common procedures worldwide, significantly contributes to climate change through both solid waste and air pollution, highlighting the urgent need for targeted interventions. Implementation faces hurdles including legal constraints and concerns about infection risks and malpractice.

METHODS: This article examines federal and state regulatory structures around two key waste reduction strategies: reduction of multidose medications and distribution of partly-used operating room medication to patients post-surgery.

RESULTS: We find little-to-no legitimate regulatory barriers to either waste reduction practice. Dispensing and redistributing partly-used medication has been codified in law in some states. Evidence-based reports indicate minimal risks …


Unlocking Inexpensive Training Through Overcoming Weaknesses In Dataset Distillation, Connor Wilhelm Apr 2026

Unlocking Inexpensive Training Through Overcoming Weaknesses In Dataset Distillation, Connor Wilhelm

Theses and Dissertations

Dataset distillation is a nascent technique that promises accelerated neural network training. In particular, distillation produces a highly compressed dataset that can train a neural network in as little as a single optimization step. However, distillation has not been adopted for real-world use cases due to weaknesses, such as poor approximation of the original task, unclear interpretability, high costs of the initial distillation, and poorly elaborated use cases. Here, we present five papers that advance task distillation towards real-world adoption. The papers focus on: distilling reinforcement learning environments, interpreting distillation-produced datasets, improving distillation performance using ensembling, examining distillation's generalization to …


Climate Change And Transportation, Paul J. Marchese Apr 2026

Climate Change And Transportation, Paul J. Marchese

Open Educational Resources

This module examines how climate change is affecting transportation systems across multiple sectors, including roads, rail, air, maritime, and active transportation. It highlights key climate trends such as rising temperatures, sea level rise, and extreme weather, and explains how these factors disrupt infrastructure, operations, and safety. The module also explores the economic, operational, and policy challenges associated with maintaining resilient transportation systems under changing environmental conditions. Finally, it presents a range of adaptation and mitigation strategies, emphasizing engineering solutions, sustainable technologies, and data-driven decision-making.


Understanding The Role Of Tiktok As A Source Of Support For Cyberbullying Victims, Saba Iqbal Apr 2026

Understanding The Role Of Tiktok As A Source Of Support For Cyberbullying Victims, Saba Iqbal

Theses and Dissertations

Cyberbullying poses a significant threat to teenagers and young adults, who often seek support and advice online. Little is known about the support and advice shared online for victims of cyberbullying and whether it is helpful. In this study, we used qualitative thematic analysis to examine a sample of 150 TikTok videos that give support or advice for cyberbullying victims. We identify 33 unique pieces of support and advice across 5 categories, with differences in tone and delivery among different types of videos. We then evaluated the quality of 33 unique pieces of cyberbullying advice in a user study with …


The Impact Of An Interactive Open Education Textbook For An Undergraduate Introductory Chemistry Course For Nonmajors, Erin Avram Apr 2026

The Impact Of An Interactive Open Education Textbook For An Undergraduate Introductory Chemistry Course For Nonmajors, Erin Avram

Chemistry Faculty Publications

Reading informational text is a critical skill across most professions. Unfortunately, students are less likely to purchase the required course materials now compared to 2010. A free, interactive text was developed for an introductory chemistry course for non-STEM majors. This involved remixing existing texts and incorporating interactive activities to engage students during the learning process and provide opportunities for them to gauge their learning. Based on the results of a student survey, 82% of students reported that it was very important to them that the text was free and 80% of students who responded reported that they used the eText …


Engineering Ferrate(Vi) For Water And Wastewater Treatment: Translating Science Into Technology, Zepei Tang, Zhenli He, Yang Deng Apr 2026

Engineering Ferrate(Vi) For Water And Wastewater Treatment: Translating Science Into Technology, Zepei Tang, Zhenli He, Yang Deng

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Over the past five decades, ferrate(VI) (FeO42–) for water and wastewater treatment has remained largely at the laboratory scale, with limited pilot- and full-scale implementation. This gap between sustained research and scarce real-world deployment places the technology in the Valley of Death─a high-risk stage of development─and highlights the need for an engineering-centric approach to enable practical application. This article presents an engineering framework to guide the development and translation of ferrate(VI) technology for water and wastewater treatment. From a system perspective, ferrate(VI) technology comprises three core subsystems: generation, treatment, and solid–liquid separation. Technology maturity depends on both the advancement of …


Electroenzymatic Cascades For Nitrogen Upgrading: Beyond Ammonia Towards Value-Added Nitrogen Chemicals, Rohit G. Jadhav, Vamshi Krishna Kamaja, Wassim El Housseini, Monica Brachi, Shelley D. Minteer Apr 2026

Electroenzymatic Cascades For Nitrogen Upgrading: Beyond Ammonia Towards Value-Added Nitrogen Chemicals, Rohit G. Jadhav, Vamshi Krishna Kamaja, Wassim El Housseini, Monica Brachi, Shelley D. Minteer

Chemistry Faculty Research & Creative Works

The global transition toward sustainable chemical manufacturing demands technologies that leverage natural carbon and nitrogen cycles while minimizing reliance on sacrificial reagents and fossil resources. These biogeochemical cycles are fundamental to life, and enzymes catalyze many of their key transformations. Bio electrochemical, specifically electroenzymatic, systems offer a promising route to sustainable synthesis by enabling selective redox transformations powered by electricity. However, whereas carbon-cycle enzymes are now well established in bio electrochemical synthesis, enzymes from the nitrogen cycle remain comparatively underexplored. Moreover, the nitrogen cycle alone does not access many value-added nitrogen-containing products, which require additional C-N bond formation and organic …


Quantum Scattering Of Hc5n And Para-H2 On A New Potential Energy Surface, Shan Gao, François Lique, Ernesto Quintas-Sánchez, Richard Dawes, Jérôme Loreau Apr 2026

Quantum Scattering Of Hc5n And Para-H2 On A New Potential Energy Surface, Shan Gao, François Lique, Ernesto Quintas-Sánchez, Richard Dawes, Jérôme Loreau

Chemistry Faculty Research & Creative Works

In the interstellar medium (ISM), non-local thermodynamic equilibrium situations are common due to low density, and one needs to consider the effect of molecular collisions in order to interpret the observations. Among the species detected in the ISM, cyanopolyynes, with the general molecular formula HC2n+1N (n = 1, 2, …), are characterized by large dipole moments and small rotational constants and constitute an indispensable class of candidates for the sensitive tracers of local density and temperature. We present a study of the collisional (de-) excitation of HC5N by para-H2 (p-H2) in its ground …


Drainage Proximity And Sinkhole Occurrence In Sivrihisar (Central Turkey): A Comparative Analysis Of Linear, Poisson, And Negative Binomial Regression Models, Bilge Bingül, Emrah Pekkan, Resul Çömert Apr 2026

Drainage Proximity And Sinkhole Occurrence In Sivrihisar (Central Turkey): A Comparative Analysis Of Linear, Poisson, And Negative Binomial Regression Models, Bilge Bingül, Emrah Pekkan, Resul Çömert

International Journal of Speleology

This study investigates the relationship between sinkhole occurrence and distance to drainage in the Sivrihisar region (Central Turkey) and evaluates the suitability of different regression approaches for modeling clustered count data in karst terrains. A comprehensive inventory of 104 sinkholes developed within the Neogene lacustrine limestones of the Akpınar Formation was compiled using official records, remote sensing analyses, and detailed field surveys. Sinkhole occurrences were analyzed relative to a drainage network derived from a high-resolution Digital Surface Model and grouped by proximity to drainage lines. Linear Regression (LM), Poisson Regression (PR), and Negative Binomial Regression (NBR) models were comparatively applied …


Mathematical Modeling, Analysis And Numerical Simulation Of Air Quality Using The Advection-Diffusion-Reaction Equation, Md Timorul Islam Apr 2026

Mathematical Modeling, Analysis And Numerical Simulation Of Air Quality Using The Advection-Diffusion-Reaction Equation, Md Timorul Islam

Math Theses

In this thesis, we study an air quality model by using a nonlinear one-dimensional advection-diffusion-reaction system of partial differential equations for NO-NO2-O3 chemical cycle. The model incorporates advection, diffusion, chemical reactions, and source terms, and is formulated based on standard atmospheric chemistry.

We first develop numerical methods to approximate the solutions of the governing equations. Both explicit and implicit finite difference schemes are considered, and the implicit scheme provides approximations without any restrictions on the stability.

The model is then nondimensionalized to identify key parameter combinations governing the system. This leads us to a regime in which the transport and …


When Generative Ai Is Intimate, Sexy, And Violent: Examining Not-Safe-For-Work (Nsfw) Chatbots On Flowgpt, Xian Li, Yuanning Han, Di Liu, Pengcheng An, Shuo Niu Apr 2026

When Generative Ai Is Intimate, Sexy, And Violent: Examining Not-Safe-For-Work (Nsfw) Chatbots On Flowgpt, Xian Li, Yuanning Han, Di Liu, Pengcheng An, Shuo Niu

Computer Science

Content Warning: This paper contains sexually explicit and violent images and text. User-created chatbots powered by generative AI offer new ways to share and interact with Not-Safe-For-Work (NSFW) content. However, little is known about the characteristics of these GenAI-based chatbots and their user interactions. Drawing on the functional theory of NSFW on social media, this study analyzes 376 NSFW chatbots and 307 public conversation sessions on FlowGPT. Findings identify four chatbot types: roleplay characters, story generators, image generators, and do-anything-now bots. AI Characters portraying fantasy personas and enabling hangout-style interactions are most common, often using explicit avatar images to invite …


Coral Reef Hydrodynamics: A Critical Review Of Roughness Indices And Their Characteristic Complexity, Faisal Karim, N. A. K. Nandasena, Lujain Kuruvachalil, Mohamed M. Mohamed, James P. Terry Apr 2026

Coral Reef Hydrodynamics: A Critical Review Of Roughness Indices And Their Characteristic Complexity, Faisal Karim, N. A. K. Nandasena, Lujain Kuruvachalil, Mohamed M. Mohamed, James P. Terry

All Works

This study provides a systematic review of hydrodynamic roughness in coral reef systems, focusing on drag coefficient (Cd), Manning's roughness coefficient (n), friction factor, and rugosity metrics. A structured bibliometric analysis was conducted using Scopus and Web of Science databases, including field measurements, laboratory flume experiments, and numerical studies validated with physical data. Results show substantial variability in roughness parameters across scales and environments. Reported drag coefficients range from 0.002 for smooth sandy beds to values exceeding 7.0 in complex mangrove-reef systems, with typical reef crest values between 0.05 and 0.30. Manning's n varies from 0.01 in smooth channels to …


Advancing Cyclic Ion Mobility Mass Spectrometry For Structural Characterization, Isomer Discrimination And Gas-Phase Ion Chemistry, Sudam Shivaji Mane Apr 2026

Advancing Cyclic Ion Mobility Mass Spectrometry For Structural Characterization, Isomer Discrimination And Gas-Phase Ion Chemistry, Sudam Shivaji Mane

Theses and Dissertations

This dissertation focuses on the development and application of high-resolution ion mobility-mass spectrometry (IMS-MS) methodologies for gas-phase separation and structural characterization of small molecules, with particular emphasis on epimers, positional isomers, and protomers. In addition to structural separations, this work investigates fundamental aspects of gas-phase ion chemistry using IMS-MS in combination with collision-induced ion activation and dissociation techniques. Advanced separations were performed using cyclic traveling-wave ion mobility spectrometry (cyclic TWIMS), implemented in a commercial cyclic ion mobility-mass spectrometry (cIMS) platform, to systematically evaluate both the capabilities and limitations of high-resolution IMS in resolving subtle structural differences. Initial studies demonstrated that, …