Digital Commons Network^™

Contribution Of Non-Linear Internal Waves To Marine Net Primary Production Has Been Underestimated, Xiaoju Pan, Tung-Yuan Ho, George T. F. Wong, Jen-Hua Tai, Shoude Guan, Fuh-Kuo Shiah

OES Faculty Publications

Field observations in the northern South China Sea (NSCS) indicate that elevated concentrations of chlorophyll a (Chl_a) associated with non-linear internal waves (NIWs) were more pronounced in the subsurface than at the sea-surface. At a given surface Chl_a, the vertically integrated Chl_a in an NIW-active area was 45% higher than that in an area where the NIW activities were minimal. As a result, net primary production (PP_eu) estimated from surface Chl_a from remote sensing by using the current Chl_a-based PP_eu model (e.g. VGPM) would have underestimated the true value by the same amount. If this correction is …

Autonomous Float Data Reveal Decoupled Trends In Chlorophyll And Stratification In The Indian Ocean, Marufa Ishaque, Sophie Clayton, John Klinck

OES Faculty Publications

Recent studies have shown that the Indian Ocean is warming significantly, but how this warming impacts primary production is largely unresolved due to a relative lack of depth-resolved biological observations. In this study, we have used Biogeochemical-Argo data from 2013 to 2022, comprising over 9,000 individual profiles, to examine regional patterns and trends in depth-integrated chlorophyll, depth-integrated net primary production and stratification in the northern and Equatorial Indian Ocean. Our analysis shows that water column stratification is increasing in the majority of the study area, with the highest rate of increase observed in the western Bay of Bengal. At the …

Recirculated Submarine Groundwater Discharge Dominates Nutrient Inputs And Enhances Eutrophication Risk In A Coastal Lagoon, Júlia Rodriguez-Puig, Clara Ruiz-González, Marc Diego-Feliu, Irene Alorda-Montiel, Aaron Alorda-Kleinglass, Daniel Romano-Gude, Andrea G. Bravo, Júlia Dordal-Soriano, Javier Gilabert, Sophia Bergeler, Celine Lavergne, Gemma Casas, Marisol Manzano, Jordi Garcia-Orellana, Valentí Rodellas

OES Faculty Publications

Submarine groundwater discharge (SGD) is a widely recognized pathway for nutrient transport to coastal systems. Prior studies overlook the unique biogeochemical signatures of different SGD pathways, neglecting their differences in biogeochemical transformations and spatiotemporal factors. Here, we present an integrated assessment of nutrient delivery through three SGD pathways (fresh SGD, long‐scale recirculated SGD, and short‐scale porewater exchange), alongside surface water inputs, to evaluate their seasonality and impact on nutrient dynamics in a coastal lagoon. We conducted five field surveys in March, July, and November 2021, July 2024, and March 2025 in the Mar Menor lagoon, an ecosystem facing severe ecological …

Microbial Mats In Dinosaur Ichnocoenoses, Nora Noffke, Paul C. Murphy, Roger C. Buntin, Martin G. Lockley

OES Faculty Publications

Until now, the significance of microbial mats in preservation of dinosaur tracks and in reconstructing the palaeoenvironment in which dinosaurs roamed was rarely studied. Dinosaur tracks are commonly found close to ancient aquatic bodies where moist sediment had once allowed footstep registration. At such sites, epibenthic or endobenthic microbial mats may have developed as well and may have led to exquisite track preservation. Microbial mats in coastal, lacustrine or flood plain environments cause 'microbially induced sedimentary structures—MISS', which are micobialites found in sandy or evaporitic settings. The microbial structures record environmental parameters including meteorological conditions that existed at the time …

Unintended Consequences Of Estuarine Management Within The Trajectory Of Recovery: Examples From The Chesapeake Bay, Jessica S. Turner, Fei Da, Molly M. Mitchell

OES Faculty Publications

Estuaries are vital ecosystems that support biodiversity, human populations, and economic activities such as fisheries, aquaculture, and tourism. Managing estuarine systems often involves interventions to regulate sediment and nutrient inputs with the goal of improving water quality, and subsequently the economic values of the estuary. However, these management strategies can produce unintended consequences. The Chesapeake Bay is an estuary recovering from eutrophication which provides clear case studies for these patterns. In the Chesapeake Bay, decreased sediment inputs, resulting from shoreline stabilization and watershed modifications, can impair marsh resilience to sea level rise and disrupt sediment-light-algal interactions affecting water clarity. Likewise, …

Regional Oceanographic Controls On Water Column Nitrogen Fixation In Northern Australian Waters, Douglas G. Capone, Ajit Subramaniam, Yubin Raut, Joseph P. Montoya, Margaret R. Mulholland, Rachel Ann Foster, Miles Furnas, Edward J. Carpenter

OES Faculty Publications

Large blooms of the diazotrophic cyanobacteria, Trichodesmium, have been re-ported along the north coast of Australia and are readily evident in remote sensing images. During a research cruise in November 1999, we sampled from Townsville to Broome, examined Trichodesmium population densities and their rates of carbon and N₂ fixation alongside microscopy-based cell counts of them and other cyanobacte-rial diazotrophs. Additionally, we also enumerated the picophytoplankton community using flow-cytometry, measured bulk chlorophyll concentrations, carbon and N₂ fixation rates, and water column hydrography, enabling comparison of diazotrophic and picophytoplankton functional groups across the system. Agglomerative hierarchical clustering analysis of physicochemical oceanographic …

Efficient Preservation Of Old Methane-Derived Organic Carbon In Deep-Sea Surface Sediments, Rui Bao, Yangli Che, Mingzhi Liu, Naiyu Zhang, Yang Zhou, Lihua Dong, Shen Li, Owen A. Sherwood, Min Yu, Zongheng Chen, Shengxiong Yang, Nan Wang, Longhai Zhu, Jiawang Chen, Mutai Bao, Haoshuai Li, Luonan Chen, Weifeng Wu, Haiyue Ma, David J. Burdige

OES Faculty Publications

Methane released from the subseafloor is significantly attenuated during upward migration, yet the preservation of methane-derived organic carbon (OC) in global deep-sea sediments remains poorly understood. Here, we measured carbon isotopes coupled with temperature-ramped analyses on various methane seepage sediments. Our results reveal a correlation between the radiocarbon (¹⁴)C) content in deep-sea surface sediments and sulfate-methane transition depth. Notably, our findings suggest that a substantial amount of (¹⁴)C-depleted OC may originate from deep-seated methane and is efficiently preserved in surface seepage sediments. We propose that the efficient OC preservation is related to microbial-mediated aggregate formation at the seawater-sediment interface, where …

The Effects Of A Microplate On Plume-Ridge Interactions: Constraints From Comparing Easter And Juan Fernandez Microplates In The Eastern Pacific Ocean, Katherine Ames, Jennifer Georgen

OES Faculty Publications

This study investigates the nature of plume-ridge interactions near a tectonic microplate using mantle Bouguer anomaly (MBA) gravity calculations. The focus of this investigation is a comparison of the Easter and Juan Fernandez microplates, which are located in the eastern Pacific Ocean along the Pacific, Nazca, and Antarctic plate boundaries. The microplates have several similar characteristics, including general size, time of formation, and clockwise rotation within the larger bounding mid-ocean ridge systems. Unlike the Juan Fernandez microplate, however, the Easter microplate is located near a mantle plume (Easter/Salas y Gomez). Previously published geochemical data suggest that material from this plume …

Visualizing The Barely Detectable: Particle Characteristics Of The Elusive Aquatic Gel Phase In The Northeastern Subtropical Atlantic, Huanqing Huang, María Couret, Santiago Hernández-León, Alexander B. Bochdansky

OES Faculty Publications

Marine gels constitute a large yet poorly explored ocean carbon pool. Shadow imaging was tuned to detect particles at two sensitivity levels: high–optical density particles (HODP), resembling the particles captured by most imaging systems, and low–optical density particles (LODP), representing a vastly more abundant and gel-dominated pool. This method enabled us to map and characterize a portion of oceanic gels without filtration and staining. In the subtropical northeast Atlantic, LODP outnumbered HODP of the same size by one or two orders of magnitude. Morphology and particle number spectra differed greatly between the two pools, with LODP showing greater morphological homogeneity …

Microplastics Suppress Copepod Grazing Of The Harmful Algal Bloom-Forming Dinoflagellate, Alexandrium Catenella, Megan Ladds, Christopher Gobler

OES Faculty Publications

While harmful algal blooms (HABs) are prominent occurrences in coastal zones where microplastic concentrations are maximal, the manner in which microplastics may influence food webs and HABs is poorly understood. This study explored how polystyrene microplastics affected copepod grazing of the saxitoxin-synthesizing harmful dinoflagellate, Alexandrium catenella, as well as a non-toxic dinoflagellate, Gymnodinium aureolum. Experiments were performed using multiple densities of microplastics (250 – 10,000 mL^–¹) of differing sizes (4 and 10 µm), as well as multiple densities of microalgae in microplates. The addition of 10 µm microplastics at densities of 1000 – 10,000 beads mL^{– …}

Remote Sensing Of Particulate Organic Carbon And Phytoplankton Carbon In The Northern South China Sea, Xiaoju Pan, Tung-Yuan Ho, George T. F. Wong, Jen-Hua Tai, Lijuan Nie

OES Faculty Publications

Surface concentrations of particulate organic carbon (POC) and phytoplankton carbon (C_phy) in the northern South China Sea (NSCS) have been assessed successfully by remote sensing with appropriate regional tuning. Match-up comparisons between satellite derivations and field observations showed uncertainties of ± 28.5% for POC and ± 37.0% for C_phy. The satellite-derived climatological distributions are consistent with previous reports. In the open NSCS where phytoplankton growth is controlled primarily by the convective overturn, both POC and C_phy are higher in winter, associating with the effect of stronger northeast monsoons and surface cooling, than in summer, when …

Differences In Sideerophore Production During The Growth Of Phytoplankton In Southern Ocean Incubation Experiments Under High- And Low-Iron Conditions, Randelle M. Bundy, Kristen N. Buck, Bethany D. Jenkins, P. Dreux Chappell, Daniel J. Repeta, Alexa Sterling, Shannon M. Yang, Laura Holland, Léo Mahieu, Laura E. Moore

OES Faculty Publications

Iron is an important micronutrient required by marine microorganisms. The Southern Ocean is an ecosystem where primary production is limited by the availability of iron, but how microorganisms in this region adapt to low-iron conditions or respond to episodic iron inputs is understudied. We tested how external iron additions would impact bacterial production of siderophores during phytoplankton growth using shipboard incubation experiments under a range of iron conditions. Similar heterotrophic bacteria communities and phytoplankton biomass were observed whether iron was added from the continental margin or as inorganic iron. Under both high- and low-iron conditions, the heterotrophic bacteria community remained …

Different Last Millennium El Niño Southern Oscillation Sea Surface Temperature Patterns Drive Disparate North Atlantic Tropical Cyclone Characteristics, Elizabeth Wallace, Sylvia Dee, Andrew Bierbower, Xinyue Luo, Richard Sullivan, Wenchang Yang, Gabe Vecchi, Kerry Emanuel

OES Faculty Publications

Understanding the relationship between the El Niño-Southern Oscillation (ENSO) phenomenon and North Atlantic tropical cyclone (TC) activity is critical for both seasonal predictions and future projections of TCs. Unfortunately, the satellite observational era (1970-present) captures too few El Niño events to fully characterize the response of TC activity to this multivariate, multi-scalar, and non-linear climate phenomenon. Here we explore ENSO-TC teleconnections using large data sets (>100 k) of synthetic North Atlantic tropical cyclones simulated for the past millennium using three different climate reconstructions - two earth system models (Max Planck Institute, Community Earth System Model) and one paleoclimate data …

Water Mass Dynamics Drive Nitrogen Fixation Rates And Diazotroph Community Composition In The Coastal Region, Katherine E. Crider, Corday R. Selden, Kimberly Powell, Sing-How Tuo, Michael Muglia, Patterson Taylor, Margaret R. Mulholland, P. Dreux Chappell

OES Faculty Publications

Although significant N₂ fixation rates (NFRs) have been observed throughout mid-Atlantic coastal waters, studies have been limited in their temporal coverage, and the methods used to detect nitrogen fixers (diazotrophs) and their findings have varied. This study investigated NFRs and diazotroph communities in a dynamic coastal setting between Nags Head and Pea Island, North Carolina, USA, during a monthly time series from June 2019 to August 2020, and an August 2019 cruise. We observed movement of the Cape Hatteras Front and distinct NFRs and diazotroph communities in the Mid-Atlantic Bight, South-Atlantic Bight, Chesapeake Bay and Oregon Inlet plume waters, and …

Decoupling Of Dissolved Iron And Iron-Binding Humic-Like Substances Along The West Antarctic Peninsula, Laura E. Moore, Alayna Kisiday, Shannon M. Yang, P. Dreux Chappell, Randelle M. Bundy, Bethany D. Jenkins, Kristen N. Buck

OES Faculty Publications

The chemical speciation of iron (Fe) has important ramifications for the stabilization, transport, and bioavailability of this critical nutrient. Organic ligands mediate dissolved Fe biogeochemistry such that ligand concentration and molecular composition help shape dissolved Fe distributions. Electroactive Fe-binding humic-like substances ("humic substances") are one such class of ligands, a mixture thought to be predominantly comprised of degradation products of marine and terrestrial origin. Here, we examine the distributions of humic substances across large environmental gradients in dissolved Fe along the West Antarctic Peninsula in early austral spring. We found that the distributions of humic substances and dissolved Fe were …

Plasma Proteomic Profile Of Dietary Potassium And Incident Ckd, Bing Yu, Casey M Rebholz

Faculty, Staff and Student Publications

Background:: There is a need for objective biomarkers of dietary potassium. The mechanisms through which dietary potassium influences kidney health are incompletely understood.

Methods:: Atherosclerosis Risk in Communities study participants at visit 3 (1993–1995) with dietary and proteomics data were randomly divided into discovery (N=6,814) and replication (N=3,380) sets. We examined associations between dietary potassium and 4,955 aptamers using multivariable linear regression, adjusting for sociodemographic factors, health behaviors, and estimated glomerular filtration rate, with a false discovery rate of 0.05. Then, we tested the prospective associations between potassium-related proteins and incident chronic kidney disease (CKD).

Results:: …

Understanding Practices Of Lactation And Infant Feeding Together With Women With Hiv: The Uplift Observational Study Protocol, Hulin Wu, Carly Hoffmann, Ciarra Brown, Angela B Hutchinson, K Rivet Amico, Ifeyinwa V Asiodu, Elizabeth J Mcfarland, Margaret A Lampe, Preetam A Cholli, Olga Varechtchouk, Allahna Esber, Athena P Kourtis, Lisa Abuogi

Faculty, Staff and Student Publications

Introduction: There is a limited understanding of infant feeding decisions, practices, and outcomes for women living with HIV (WLHIV) and their infants since U.S. guidelines were updated in 2023 to support breastfeeding for virally suppressed women on antiretroviral treatment.

Methods and analysis: The Understanding Practices of Lactation and Infant Feeding Together with women with HIV (UPLIFT) study is a convergent mixed-methods, multisite, observational study designed to address key knowledge gaps. Twelve US sites will begin enrollment in early 2026 to accomplish three core activities (CA). In CA1, we explore infant feeding decision-making and experiences via in-depth interviews with pregnant/postpartum WLHIV …

How To Build A Black Girl Traphouse:A Meditation And Manual For Black Feminist Survival In And Beyond The Academy, Loren Cahill, Brandyn-Dior Mckinley, Arianne Napier-White, Janae Peters, Jalisa Williams

School for Social Work: Faculty Publications

By design, the university is a colonizing, racializing, and classed space, built through unequal structures that perpetuate systemic violence (Peña, 2022). When many marginalized folks enter any university setting, they are marred by projections, judgments, assumptions, and assaults by those who question their worth, ability, and competence (y Muhs, Niemann, González, & Harris, 2012). Discriminatory actions and attitudes endured by Black women in academia often make us severely angry as well as mentally andphysically ill. Many of us are so traumatized that we choose to leave and/or are pushed out of our jobs. Those of us who choose to stay …

Likelihood-Based Inference For Random Networks With Changepoints, Daniel Cirkovic, Tiandong Wang, Xianyang Zhang

Mathematical and Statistical Science Faculty Research and Publications

Generative, temporal network models play an important role in analyzing the dependence structure and evolution patterns of complex networks. Due to the complicated nature of real network data, it is often naive to assume that the underlying data-generative mechanism itself is invariant with time. Such observation leads to the study of changepoints or sudden shifts in the distributional structure of the evolving network. In this paper, we propose a likelihood-based methodology to detect changepoints in undirected, affine preferential attachment networks where, upon introduction, a new node selects one old to attach to with probability proportional to its degree. In particular, …

4th Circuit Panel Rejects Challenge To Defense Department Ban On Enlisting People Living With Hiv Infection, Arthur S. Leonard

Other Publications

No abstract provided.

Civil Litigation Notes, Arthur S. Leonard

Other Publications

No abstract provided.

U.S. Supreme Court Rules A State Ban On Conversion Therapy For Minors Probably Violates The Free Speech Rights Of A Licensed Counselor Who Allegedly Performs Only “Talk Therapy”, Arthur S. Leonard

Other Publications

No abstract provided.

Predicting Oil Contamination In Water Using Machine Learning On Microbial Compositions, Tong Gao, Isaac Bigcraft, Stephen Techtmann, Issei Nakamura

Michigan Tech Publications

We present a compact and generative machine-learning framework that predicts oil contamination based on microbial community compositions from experimental samples. Our method combines dimensionality reduction with data augmentation and generative modeling to address high-dimensional, non-linear, and sparse microbial data. To reduce the 503-dimensional bacterial composition dataset, we compared three dimensionality reduction techniques: feature importance from random forest, principal component analysis (PCA), and t-distributed stochastic neighbor embedding (t-SNE). Feature importance outperformed PCA and t-SNE, improving predictive performance and identifying microbial species most strongly correlated with oil contamination. To mitigate data scarcity, we augmented the training data using an augmented data neural …

Large Aerosol Particles Favor Haze Conditions Through Limitations On Water Budget And Activation Kinetics, Hamed F. Sadi, Ernie Lewis, Kadja Flore Gali, Fan Yang, Jesse Anderson, Suryadev Pratap Singh, Jae Min Yeom, Will Cantrell, Raymond Shaw

Michigan Tech Publications

Experiments in the Pi Convection‐Cloud Chamber conducted by systematically changing the diameter of injected dry aerosol particles while holding the temperature difference constant demonstrate that dry diameter strongly influences the onset of haze‐dominated conditions. Two factors contribute: the system becomes water‐limited, resulting in reduction of supersaturation by growing aerosol particles to the activation diameter; and the activation process becomes kinetically limited. Dry aerosol diameter exerts a strong influence on activation time, with a power‐law exponent of 9/2. Kinetically limited activation occurs when the ratio of the activation and droplet residence times is greater than unity. The findings demonstrate that a …

Equity And Justice In Water Pricing And The Effects On Water Distribution System Management, Brian Barkdoll

Michigan Tech Publications

Equity regarding access to potable water is paramount. Municipal Water Distribution Systems supply potable water to users and are essential to public health. To find the optimal price of water to maximize utility revenue and allow changes to the system components for capital and maintenance expenditures, network modeling was performed for 15 real MDWSs. A new power-law price-usage elasticity curve, entitled the Power Law Elasticity Function (PLEF), was used that allowed for various users, both high- and low-income, and a non-discretionary level of usage. It was found that: (1) the maximum profit was obtained when the price was approximately 0.8 …

Population-Based Analysis Of Synergistic Effects Of Functional Disability And Comorbidities On Retention In Hiv Care Among People With Hiv, Charles Darkoh

Faculty, Staff and Student Publications

Objective: This cross-sectional study examined how types of disability and comorbidities influence retention in care (RIC) among people with HIV (PWH) in Houston/Harris County, Texas, USA.

Methods: Data from 1142 participants in the Houston Medical Monitoring Project (2015–2021) were analyzed. Descriptive statistics, bivariate analyses, and multivariable logistic regression were used to evaluate factors associated with RIC.

Results: Approximately 74.9% of participants were retained in care. Compared to PWH without specific comorbidities, those with dyslipidemia and kidney disease had higher odds of RIC (AOR: 2.66; 95% CI: 1.40–5.03 and AOR: 14.08; 95% CI: 1.44–138.12, respectively). PWH reporting only mobility disability had …

The Holistic Healing Source Scholarly Anthology Volume 1 (2026), Kimberly Johnson

Psychology: Faculty Publications

• Breaking Generational Curses: The Struggle of Achieving Peace and Prosperity Coming from an Under-Resourced Family: Explores the biological and systemic barriers marginalized families face, offering strength-based frameworks for breaking cycles of poverty and trauma.

Subgroup Identification Of Disparities In Buprenorphine Discontinuation In Opioid-Use Disorder: A Virtual Twins Machine Learning Approach Using Nationwide United States Claims Data, 2006–2022, Yuanxiong Guo

Faculty, Staff and Student Publications

Buprenorphine retention is crucial for effective treatment of opioid use disorder (OUD), yet disparities in treatment discontinuation persist. This study aims to identify and quantify disparities in buprenorphine treatment retention using a machine learning framework adapted from Virtual Twins approach focusing on disparities related to sex, age, insurance type, geographic region, mental health status and community-level Social Vulnerability Index (SVI). Using a nationwide longitudinal cohort, we applied a two-stage machine learning approach. In Stage one, we trained classification models to estimate the counterfactual differences in treatment discontinuation across disparity types. Model performance was assessed using C-statistics and precision-recall curve. In …

“If He Did It, I Can Do It, Too. I Can Change My Life Around”: The Social Model Of Recovery Within The Context Of Recovery Homes Accepting Residents Prescribed Medications For Opioid Use Disorder

Faculty, Staff and Student Publications

Introduction: This paper provides an in-depth examination of examines four recovery residences, that serve individuals prescribed medications for opioid use disorder (MOUD). The study has two primary aims: first, to deepen understanding of how recovery residences adopt and operationalize Social Model of Recovery principles; and second, to identify gaps in staff integration of residents receiving MOUD-gaps that may either support or undermine the integrity of the social model within these settings.

Methods: We conducted semi-structured interviews with 17 residents receiving MOUD living in four participating recovery homes. The interviews were conducted between August 2022 and January 2024 using a semi-structured …

Feasibility And Preliminary Outcomes Of A Remotely-Delivered Exercise Training Intervention For English-Speaking Hispanics/Latinos With Multiple Sclerosis: Results From The Ferla Ms Study, Augusto Miravalle

Faculty, Staff and Student Publications

Background: There is limited evidence on the feasibility of remotely delivered exercise interventions for English-speaking Hispanics/Latinos with MS.

Objectives: To evaluate the feasibility and exploratory efficacy of a remotely-delivered, home-based exercise program for English-speaking Hispanics/Latinos with MS and to explore associations among feasibility metrics, outcomes, and social determinants of health (SDOH).

Results: Of 340 individuals contacted, 112 were eligible (33%), 33 enrolled (9.7%), 30 randomized, and 26 completed (87% retention). Adherence averaged 81% (exercise) and 89% (control). No serious adverse events occurred. Exploratory within-group improvements were observed in the exercise group for physical activity (p = 0.03, d = …