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Articles 31 - 60 of 10137
Full-Text Articles in Entire DC Network
Improving Fairness On Semantic Segmentation Using Large Language Models, Samuel E. Burggraf
Improving Fairness On Semantic Segmentation Using Large Language Models, Samuel E. Burggraf
Electrical & Computer Engineering Projects for D. Eng. Degree
As machine learning systems are increasingly integrated into critical decision-making processes, ensuring fairness in their design and implementation has become a significant concern. While fairness research has primarily focused on specific protected attributes, less attention has been given to spatial fairness, which can affect individuals at specific locations. If fairness is not addressed, models may systematically underperform in certain regions or across populations which can lead to unequal access to accurate predictions and potentially biased decision-making. Fairness considerations should extend across all machine learning applications to align with the National Institute of Standards and Technology (NIST) guidelines of fair and …
Temperature-Induced Uncertainty In Fixed-Context Retrieval-Augmented Generation, Steven Zeng, Murat Kuzlu
Temperature-Induced Uncertainty In Fixed-Context Retrieval-Augmented Generation, Steven Zeng, Murat Kuzlu
Cybersecurity Undergraduate Research Showcase
This study examines how decoding temperature affects output uncertainty in a fixed-context retrieval-augmented generation (RAG) system. We define uncertainty as the semantic dispersion among repeated answers under the same fixed retrieved context, with greater dispersion interpreted as higher uncertainty. To isolate this answer-generation variability from retrieval drift, each question was paired with a fixed retrieved context, and repeated generations differed only in temperature. The experiment used nine questions drawn from a machine-learning textbook corpus, with three questions each at easy, moderate, and hard difficulty. Each question was evaluated at five temperatures (0.0, 0.25, 0.5, 0.75, and 1.0) over 30 iterations, …
Phishing Restraint: University Simulated Phishing Campaigns, Alexander M. Abou Khir
Phishing Restraint: University Simulated Phishing Campaigns, Alexander M. Abou Khir
Cybersecurity Undergraduate Research Showcase
Universities face heightened vulnerability to phishing attacks due to their open information-sharing culture and diverse user populations. This study examines how phishing exploits human factors within campus environments and evaluates three major training strategies: embedded phishing, microlearning, and role-based instruction to understand their individual and combined effectiveness. I explored studies that implement these strategies in pairs and use the strategies alone, identified trends in susceptibility reduction, behavioral reinforcement, and contextual relevance. I suggest that, while each method independently improves user awareness, multiple approaches offer stronger, more adaptable protection by addressing both psychological triggers and role-specific risks. The paper contributes a …
Hijacking The Prompt: A Survey Of Prompt Injection Attacks, Detection, And Defense In Large Language Models, Edward J. Griggs
Hijacking The Prompt: A Survey Of Prompt Injection Attacks, Detection, And Defense In Large Language Models, Edward J. Griggs
Cybersecurity Undergraduate Research Showcase
Prompt injection attacks, ranked the number-one vulnerability in AI systems by OWASP's 2025 Top 10 for Large Language Model Applications, remain largely unsolved, and this survey examines why. As large language models (LLMs) are deployed across enterprise workflows, agentic systems, and consumer tools, their fundamental inability to distinguish trusted instructions from untrusted user data has created a persistent and expanding attack surface. This paper presents a structured taxonomy of prompt injection attack vectors, including direct injection, indirect injection, multimodal attacks, tool and agent exploitation, hybrid chained techniques, and autonomous propagating threats. These vectors are mapped across five impact categories (data …
Limitations Of Signature-Based Network Intrusion Detection Under Modern Traffic Conditions, Henry Guidry
Limitations Of Signature-Based Network Intrusion Detection Under Modern Traffic Conditions, Henry Guidry
Cybersecurity Undergraduate Research Showcase
Network Intrusion Detection Systems are tools used to monitor network traffic and alert to suspicious or harmful activity before it can cause harm. Signature-based versions of these systems are a foundation for intrusion detection, operating by finding common patterns and forming malicious signatures. However, three developments in modern network environments have greatly impacted the significance of Network Intrusion Detection Systems. These three developments are the near-complete adoption of end-to-end encryption, the use of sophisticated packet fragmentation techniques, and the processing demands of high-throughput networks. Encryption makes deep packet inspection practically infeasible by transforming inspectable payloads into ciphertext, forcing NIDS to …
Artificial Intelligence Moderation In Online Gaming: A Cybersecurity Analysis Of Risks And Defenses, Labib Khan
Artificial Intelligence Moderation In Online Gaming: A Cybersecurity Analysis Of Risks And Defenses, Labib Khan
Cybersecurity Undergraduate Research Showcase
This research paper will examine the role of artificial intelligence (AI) moderation systems in enhancing cybersecurity within online gaming environments. As multiplayer platforms increasingly rely on real-time text, voice communication, and user-generated content, developers have implemented AI-driven tools such as natural language processing (NLP), speech recognition, and behavioral analytics to detect harassment, toxic behavior, cheating coordination, and other malicious activity. These systems enable gaming companies to efficiently monitor large volumes of player interactions, improving response times and helping maintain safer and more controlled digital environments for users across global gaming communities of varying sizes and activity levels.
While these technologies …
Escaping Isolation: An Analysis Of Virtual Machine And Container Breakout Vulnerabilities, Felix Iov
Escaping Isolation: An Analysis Of Virtual Machine And Container Breakout Vulnerabilities, Felix Iov
Cybersecurity Undergraduate Research Showcase
Cloud computing providers rely on multi-tenant architectures to maximize resource efficiency. This infrastructure depends on virtualization, which provides isolation between clients. This comes primarily in the form of Virtual Machines (VMs) and Containers. However, “breakout attacks” or “escapes” are a critical threat where attackers bypass these isolation layers to gain unauthorized access to the host system and neighboring environments. This paper surveys virtualization escape threats and analyzes three case studies: a runc container escape (Leaky Vessels), a VMware ESXi VM escape (VSOCKPuppet), and an NVIDIA GPU container escape (NVIDIAScape). Each demonstrates different attack surfaces, including file descriptor misuse, kernel driver …
Bio-Cybersecurity: Securing The Healthcare Industry, Amanda D. Coleman
Bio-Cybersecurity: Securing The Healthcare Industry, Amanda D. Coleman
Cybersecurity Undergraduate Research Showcase
Bio-cybersecurity refers to the aspect of cybersecurity that applies to the biological sciences and the protection of digital biomedical information. Today’s healthcare industry has evolved with the enhancement of internet and biomedical technology. While hospitals and private medical providers remain compliant with the Health Information Portability and Accountability Act (HIPAA) through traditional means of securing documented patient information, the emergence of beneficial internet-based healthcare services like virtual appointments and digital patient records requires new policies and healthcare cybersecurity frameworks to protect sensitive information from unauthorized access. This paper examines the role of cybersecurity in healthcare, the vulnerabilities that exist and …
Ai's Double Edged Sword: Fighting Against Synthetic Csam, Shekhinah Adra Green
Ai's Double Edged Sword: Fighting Against Synthetic Csam, Shekhinah Adra Green
Cybersecurity Undergraduate Research Showcase
The rapid advancements in generative artificial intelligence has introduced new challenges in the production and distribution of synthetic child sexual abuse material (CSAM). AI has the capabilities of creating highly realistic imagery and videos, which raises serious legal and ethical concerns, increasing the risk of harm, exploitation, and revictimization.
This paper discusses the legal improvements needed in order to lower the change of legal loopholes, how digital forensic analyst use advanced tools to identify and investigate synthetic material, and different methods to start the reduction of synthetic CSAM.
Enhancing Urban Garden Capacity By Linking Biodiversity And Ecosystem Function, Mary T. Nguyen, Carleen Rauh, Shelby Gresch, Charlotte Correiro, Heidi Elmendorf, Adriane Fugh-Berman, Gina Wimp, Alexandra L. Decandia
Enhancing Urban Garden Capacity By Linking Biodiversity And Ecosystem Function, Mary T. Nguyen, Carleen Rauh, Shelby Gresch, Charlotte Correiro, Heidi Elmendorf, Adriane Fugh-Berman, Gina Wimp, Alexandra L. Decandia
Virginia Journal of Science
Urban agriculture broadly describes food and plant cultivation in metropolitan areas. While biodiversity is thought to support ecosystem health and resilience, the relationship between above-ground and below-ground diversity has been understudied in urban green spaces. This study examines plant, animal, bacterial, and fungal diversity across three distinct urban habitats: a turf lawn, a forb garden, and a farming space. Using bacterial 16S rRNA and fungal ITS2 sequencing, soil nutrient analyses, and surveys of vegetation and wildlife, we connect diverse philosophies in urban agriculture to their role in advancing community diversity and ecosystem function. We found that different urban gardens support …
Program: Virginia Academy Of Science 104th Annual Meeting, 2026, Virginia Academy Of Science
Program: Virginia Academy Of Science 104th Annual Meeting, 2026, Virginia Academy Of Science
Virginia Journal of Science
Full program of the 104th Annual Meeting of the Virginia Academy of Science. Held at Christopher Newport University, Newport News, Virginia on May 28, 2026.
Proceedings Of The 104th Annual Virginia Academy Of Science Meeting, 2026, Virginia Academy Of Science
Proceedings Of The 104th Annual Virginia Academy Of Science Meeting, 2026, Virginia Academy Of Science
Virginia Journal of Science
Proceedings (abstracts) of the 104th Annual Meeting of the Virginia Academy of Science, May 28, 2026, at Christopher Newport University, in Newport News, Virginia.
The Psychology Behind Ai-Generated Phishing And Social Engineering Attacks, A’Shya Reynolds
The Psychology Behind Ai-Generated Phishing And Social Engineering Attacks, A’Shya Reynolds
School of Cybersecurity Master's Level Projects and Papers
Cybercrime has evolved significantly with the integration of artificial intelligence (AI), transforming traditional phishing and social engineering attacks into highly sophisticated and personalized threats. While early phishing attempts relied on generic messaging and low success rates, modern AI-driven attacks leverage advanced data analytics, natural language processing, and behavioral prediction to manipulate victims more effectively.
This research examines how cybercriminals utilize AI to enhance psychological manipulation techniques in phishing and social engineering attacks, increasing victim susceptibility. Drawing from interdisciplinary literature in cybersecurity and psychology, this study explores key psychological mechanisms, including cognitive biases, emotional triggers, and decision-making processes that influence victim …
Pushing High-Performance Private Inference Towards Resource-Constrained Edge Clients, Xiangrui Xu
Pushing High-Performance Private Inference Towards Resource-Constrained Edge Clients, Xiangrui Xu
Computer Science Theses & Dissertations
The widespread adoption of Machine Learning as a Service (MLaaS) has enabled resource constrained edge clients, such as mobile and IoT devices, to leverage powerful deep learning mod els hosted on the cloud. However, this paradigm introduces critical privacy challenges regarding the client’s sensitive input data and the server’s proprietary model parameters. While cryptographic techniques like Homomorphic Encryption (HE) and Multi-Party Computation (MPC) enable Private Inference (PI), existing frameworks impose prohibitive computational and communication overheads that render them impractical for edge deployment. This dissertation introduces three novel frameworks—SPOT, LUTless, and PrivShap—to systematically address the efficiency bottlenecks of PI in edge …
Downstream Effects Of Post Aerobic Digestion And Divalent Cation Treatment: Dewaterability, Phosphorus Mitigation, And Process Odors, Maya Marisol Quijano Garcia
Downstream Effects Of Post Aerobic Digestion And Divalent Cation Treatment: Dewaterability, Phosphorus Mitigation, And Process Odors, Maya Marisol Quijano Garcia
Civil & Environmental Engineering Theses & Dissertations
This study evaluated post-aerobic digestion (PAD) with aeration, mixing, and divalent cation addition to improve phosphorus capture, dewaterability, and odor control in thermal hydrolysis process (THP)–treated anaerobic digestate at the Hampton Roads Sanitation District’s Atlantic Treatment Plant. A three-day PAD process was operated under constant air flow (5 LPM) and dissolved oxygen (DO)-setpoint (0.2 mg/L) aeration conditions with Ca(OH)₂ or Mg(OH)₂ dosing. Aeration and mixing alone increased polymer demand by 14–46 % relative to untreated influent, indicating enhanced extracellular polymeric substance release. Chemical conditioning partially mitigated this increase but did not restore polymer demand to baseline levels. Dewatered cake total …
Learning Techniques In Prediction Of Functional Epigenomic Events, Mohammad Shiri
Learning Techniques In Prediction Of Functional Epigenomic Events, Mohammad Shiri
Computer Science Theses & Dissertations
Accurately predicting functional epigenomic events from DNA sequences is critical to understanding gene regulation and the functional impact of non-coding variants. Despite considerable progress, critical challenges hamper the effectiveness and efficiency of existing deep learning approaches. These challenges include negative transfer in multi-task learning (MTL), suboptimal network architectures, and pervasive label noise, particularly the positive-unlabeled problem arising from data sparsity in single-cell assays. This dissertation presents a cohesive framework of novel learning techniques to effectively address these challenges. First, a highly scalable task grouping framework is presented to mitigate negative transfer in deep MTL. This method clusters tasks based on …
Radicals Transforming Organic Matter: Implications For Non-Pyrogenic Black Carbon And Nitrogen Formation, Molecular Dynamics In Tropical Soils, And Lignin Valorization, João Vitor Dos Santos
Radicals Transforming Organic Matter: Implications For Non-Pyrogenic Black Carbon And Nitrogen Formation, Molecular Dynamics In Tropical Soils, And Lignin Valorization, João Vitor Dos Santos
Chemistry & Biochemistry Theses & Dissertations
Radicals drive the transformation of organic matter in natural and engineered systems, altering its structure, reactivity, and stability. Condensed aromatic carbon (ConAC) and condensed aromatic nitrogen (ConAN) are among the most persistent forms of organic matter in soils and are traditionally interpreted as products of biomass burning. This dissertation challenges the long-standing assumption that these materials are exclusively pyrogenic, showing that iron-mediated radical chemistry can generate condensed aromatic structures under ambient conditions.
Chapters II and III show that Fenton-like radical oxidation of lignin-rich biomass produces condensed aromatic structures compositionally similar to pyrogenic black carbon and black nitrogen when assessed with …
Bridging Mission And Execution: Integrating Participatory Design In Early-Phase Mission Engineering For Stakeholder Alignment And Mission Clarity, Rafi Soule
Engineering Management & Systems Engineering Theses & Dissertations
This dissertation develops and evaluates an integration-centered approach to early-phase Mission Engineering that improves mission clarity under ambiguity. Stakeholder interpretations diverge, and interoperability constraints are not surfaced early. These conditions reduce mission clarity and weaken mission-to-system mapping readiness. The dissertation proposes an integration-centered approach that strengthens early mission framing through two complementary mechanisms: (1) a participatory design-inspired, artifact-first workflow that surfaces and repairs interpretation divergence, and (2) closed-corpus, RAG-enabled retrieval that grounds mission-to-system mapping in traceable evidence. The study was organized around a construct spine linking shared understanding, stakeholder alignment, and interoperability feasibility to mission clarity. A three phase mixed-methods …
Student Perceptions Of The Community Of Inquiry In Online Human Anatomy And Physiology Discussion Boards Using 2-D And 3-D Anatomical Models, Timothy J. Mcguire
Student Perceptions Of The Community Of Inquiry In Online Human Anatomy And Physiology Discussion Boards Using 2-D And 3-D Anatomical Models, Timothy J. Mcguire
EVMS School of Health Professions Theses & Dissertations
Online human anatomy and physiology (HA&P) courses require students to learn complex anatomical content outside of a physical laboratory environment, a challenge that may be supported by enhancing students’ perceptions of collaborative learning (CL) through the community of inquiry (CoI) framework. This convergent parallel mixed-methods study examined participants’ perceptions of the CoI framework during two discussion board (DB) activities in an online, asynchronous, noncredit HA&P I study course at a midwestern community college.
Participants were recruited via convenience sampling and randomly assigned to one of two instructional sequence groups (2-D→3-D or 3-D→2-D) to complete two DB activities requiring annotation of …
Perceptions Of The Community Eligibility Provision (Cep) Program, Angela H. Napier
Perceptions Of The Community Eligibility Provision (Cep) Program, Angela H. Napier
Educational Leadership & Workforce Development Theses & Dissertations
This study examined how educators and families perceive and experience the Community Eligibility Provision (CEP) and its influence on student attendance, engagement, well-being, and school climate within one public school division. While prior research has established quantitative links between universal meal programs and academic outcomes, limited research has explored how stakeholders interpret and experience these effects in practice. Addressing this gap, this study employed a convergent mixed-methods design, integrating archival attendance data, surveys, and semi-structured interviews with principals, assistant principals, teachers and families. Quantitative findings revealed modest but inconsistent changes in absenteeism following the CEP implementation, while qualitative findings provided …
The Leadership Lens: A Phenomenological Study Of The Lived Sensemaking Experiences Of School Leaders Implementing Virginia's New Standards Of Accreditation And Accountability, Paul M. Wilson Jr.
The Leadership Lens: A Phenomenological Study Of The Lived Sensemaking Experiences Of School Leaders Implementing Virginia's New Standards Of Accreditation And Accountability, Paul M. Wilson Jr.
Educational Leadership & Workforce Development Theses & Dissertations
This phenomenological study exposes the complex cognitive and organizational processes school leaders navigate as they translate high-stakes state mandates into localized action. By examining the implementation of Virginia’s revised Standards of Accreditation and Accountability (SOA), this study challenges the prevailing managerial paradigm that views policy implementation as a linear, mechanical execution of directives. Instead, grounded in sensemaking theory and SDT, this research conceptualizes implementation as a situated and interpretive act shaped by leaders’ prior experiences, beliefs, and psychological needs for autonomy, competence, and relatedness.
Using a qualitative phenomenological design, data were collected through semi structured interviews with 12 school and …
A Transcendental Phenomenological Study Of The "Intervention Implementation Experience" With Department Chairs And Program Coordinators During A Performance Improvement, Courtney W. Schoolmaster
A Transcendental Phenomenological Study Of The "Intervention Implementation Experience" With Department Chairs And Program Coordinators During A Performance Improvement, Courtney W. Schoolmaster
STEMPS Theses & Dissertations
Minimal research has been conducted on the experiences of department chairs and program coordinators with the implementation of performance improvement in learning outcome assessment. Focusing on a multidisciplinary college that offered associate degrees, technical diplomas, and certificates, located within the SACSCOC region, this transcendental phenomenology aims to understand the lived experiences of department chairs and program coordinators in a community college during the implementation/maintenance phases of a performance improvement initiative for the college’s program and general learning outcome assessment process.
This phenomenological study was conducted with eighteen department chairs and program coordinators, and two semi-structured interviews were conducted via Webex. …
The Role Of Autonomy And Motivation On Teacher Retention: A Mixed Methods Study, Jordan Overton
The Role Of Autonomy And Motivation On Teacher Retention: A Mixed Methods Study, Jordan Overton
STEMPS Theses & Dissertations
Teacher retention remains a persistent concern in the United States, with nearly 13% of classrooms unfilled by licensed teachers. Grounded in self-determination theory and basic psychological needs theory, this mixed methods sequential explanatory study examined the relationship between teacher autonomy, motivation, and intentions to leave, while also exploring the contextual factors that shaped teachers’ perceptions of autonomy within their work environments.
In the quantitative phase, survey data were collected from 123 elementary and middle school teachers across three school divisions in Southeastern Virginia. Measures included teacher autonomy, work motivation, and intentions to leave one’s school or division and the teaching …
Exclusive Neutral Pion Electroproduction Cross Section Measurements With A Neutral Particle Spectrometer, Mitchell R. Kerver
Exclusive Neutral Pion Electroproduction Cross Section Measurements With A Neutral Particle Spectrometer, Mitchell R. Kerver
Physics Theses & Dissertations
Deep Virtual Compton Scattering (DVCS), the exclusive electron-proton scattering process ep →e′p′γ, provides access to generalized parton distributions (GPDs), which correlate informa tion about the longitudinal momentum and transverse spatial structure of quarks inside the nucleon. Experiment E12-13-010 in Hall C at Jefferson Lab was designed to take high-precision measure ments of the DVCS cross section over an extended kinematic range using the newly commis sioned Neutral Particle Spectrometer (NPS). The NPS features a high-resolution electromagnetic calorimeter and a streaming data acquisition system optimized for operation at high luminosities. This thesis presents the detector and analysis work carried out to …
Dissecting The Etiology Of Alcohol Use Disorder By An Integrative Heritable Component Approach, Ivy Garrenton
Dissecting The Etiology Of Alcohol Use Disorder By An Integrative Heritable Component Approach, Ivy Garrenton
Computer Science Theses & Dissertations
Alcohol Use Disorder (AUD) is a pervasive condition characterized by complex interplay among genetic, phenotypic, and environmental factors. Although previous studies have identi fied genetic loci associated with alcohol consumption, these efforts have not captured the genetic heterogeneity and gene-environment interactions underlying AUD pathogenesis. To address this critical gap, we developed a novel statistical methodology that integrates phenotypic, genotypic, and environmental data through an environmentally modified Genetic Relationship Matrix (GRM) to derive AUD-related traits with enhanced heritability.
This approach demonstrated superior performance in both simulated and real-world datasets. Traits derived using the environmentally modified GRM exhibited significantly higher estimated heritability …
Optimization Of Niobium Film For Particle Accelerators And Quantum Applications, Bektur Abdisatarov
Optimization Of Niobium Film For Particle Accelerators And Quantum Applications, Bektur Abdisatarov
Electrical & Computer Engineering Theses & Dissertations
Niobium (Nb) films play a central role in superconducting technologies used in particle accelerators and superconducting quantum circuits. Optimizing the physical properties of Nb films is therefore critical for improving both radiofrequency (RF) performance in superconducting radiofrequency (SRF) cavities and coherence in superconducting qubits. This thesis investigates the relationship between Nb film microstructure, impurity content, and electromagnetic response across these two application domains.
For particle accelerator applications, we studied Nb films deposited using high-power impulse magnetron sputtering (HiPIMS) with DC bias onto a 1.3 GHz elliptical SRF cavity. Nb film cavities exhibit a pronounced medium-field Q-slope, limiting their achievable accelerating …
A Study Of Short-Range Correlated Pair Formation Mechanisms, Noah S. Swan
A Study Of Short-Range Correlated Pair Formation Mechanisms, Noah S. Swan
Physics Theses & Dissertations
Short-Range Correlations (SRCs) refers to pairs of nucleons that are temporary high density fluctuations with high relative momenta and lower center-of-mass momenta com pared to the nuclear Fermi momentum (kF). SRCs account for 20–25% of the nucleons in medium to heavy nuclei, make up essentially all nucleons with momentum greater than kF, and contribute most of the kinetic energy carried by nucleons in nuclei.
The existing semi-inclusive and exclusive measurements only cover a handful of light nu clei or heavy elements. This does not allow for a systematic study of the dependence of SRC pairs on nuclear mass and proton-neutron …
Observations Of An Oscillatory Mechanochemical Reaction Between Tetrathiafulvalene And Chloranilic Acid, Alastair Deans
Observations Of An Oscillatory Mechanochemical Reaction Between Tetrathiafulvalene And Chloranilic Acid, Alastair Deans
Physics Theses & Dissertations
Mechanochemistry is the study of chemical reactions driven by the input of mechanical en ergy in addition to thermal activation. Mechanochemical reactions from powders are carried out by manual grinding or milling using various types of ball mills, or in twin extruders. While mechanochemistry has great potential affording economically and environmentally advantageous “green” synthetic methods, a drawback is that its chemical mechanisms are not well understood. One example of such a reaction currently under study involves tetrathiafulvalene, an organic elec tron donor with two polymorphs (orange and brown), and chloranilic acid, an electron acceptor. Previous results show that neat grinding …
Ultra-High Vacuum Outgassing Characterization Of Thermally Processed Low-Carbon Steel For Advanced Particle Accelerator And Gravitational Wave Detector Applications, Aiman H. Al-Allaq
Ultra-High Vacuum Outgassing Characterization Of Thermally Processed Low-Carbon Steel For Advanced Particle Accelerator And Gravitational Wave Detector Applications, Aiman H. Al-Allaq
Mechanical & Aerospace Engineering Theses & Dissertations
This dissertation investigated AISI 1020 low-carbon steel as an alternative vacuum chamber material to conventional stainless steel for ultra-high vacuum (UHV) and extreme-high vacuum (XHV) applications. After a 400 °C/48 h bake, AISI 1020 tube chambers achieved a hydrogen outgassing rate of 2.4 × 10⁻¹⁶ Torr·L·s⁻¹·cm⁻², approximately 2,300 times lower than the prebaked 316L stainless-steel comparator, among the lowest hydrogen outgassing rates ever reported for an uncoated metallic vacuum chamber. Bare and magnetite-coated AISI 1020 chambers were then compared using throughput and rate-of-rise methods. The magnetite coating yielded 5× lower water outgassing at room temperature, but this advantage disappeared after …
Quantifying Nutrient Fluxes Across The Sediment-Water Interface In The Lafayette River Estuary, Adriana E. Amrhein
Quantifying Nutrient Fluxes Across The Sediment-Water Interface In The Lafayette River Estuary, Adriana E. Amrhein
OES Theses and Dissertations
The Lafayette River, a shallow, eutrophic tributary of the Chesapeake Bay, experiences seasonal harmful algal blooms (HABs). While management efforts focus on reducing external nutrient inputs, internal loading from benthic sediments remains poorly constrained. This study quantifies spatial and seasonal variability in nutrient and radium isotope fluxes across the sediment–water interface at three sites where HABs are known to initiate and represent contrasting sediment textures and hydrodynamic conditions. Sediment cores and porewater samples were collected in summer 2023 and winter 2024 to measure grain size, porosity, dissolved nutrients (NH₄⁺, NOₓ⁻, PO₄³⁻), and radionuclide activities (²²⁴Ra and ²²⁸Th). Radium isotope disequilibrium …