Digital Commons Network^™

Navigating Health Management Decisions In Pediatric Food Allergy: Exploring Caregiver Needs, Experiences, And Behaviors, Perry Allen Catlin

Dissertations (1934 -)

Food allergy (FA) is a prevalent and often severe condition affecting approximately 8% of U.S. children (Gupta et al., 2018; Robson & Assa’ad, 2024). The responsibility for daily management of FA, including making critical health management decisions, often falls to caregivers. These responsibilities can impose significant psychosocial demands on caregivers, particularly as treatment options expand and require more nuanced decision-making (Collins et al., 2024; Hamadi et al., 2024; Knibb & Jones, 2024; Lieberman, 2024; Umetsu, 2024). Caregivers' decisions are shaped by a range of individual needs, experiences, and sociodemographic characteristics (Dale & Hemmerich, 2009; Hoefel, O’Connor, et al., 2020). As …

The Local Neighborhood Interactions Shaping Tree Communities Through Ecological Disturbance And Environmental Change, Cole Doolittle

Dissertations (1934 -)

My dissertation consists of four chapters focused on understanding the factors maintaining local species diversity, addressing a central goal of ecology increasingly critical for preserving ecosystem services and human well-being in the face of climate change. Specifically, I investigate how local neighborhoods – that is, the spatial arrangement, density, and identity of nearby competitors – contribute to patterns of growth and survival along gradients of ecological disturbance and environmental change using forest tree communities as a study system. In my first chapter, I develop a conceptual framework that synthesizes why we may expect local neighborhood interactions to weaken under ecological …

Comparison Of Leveling A Deep Curve Of Spee With Extractions Versus Non-Extraction: A Biomechanical Perspective, Mitchell James Muller

Master's Theses (2009 -)

Introduction: This study evaluated and compared orthodontic forces from different archwire designs and materials used to correct a deep curve of Spee. Methods: A three-dimensional orthodontic force tester (OFT) was used to measure forces and moments exerted by archwires on brackets from central incisors to first molars. Two setups were tested: one with a full dentition from central incisor to first molar, and another simulating bicuspid extractions with the first premolar removed. Dentoform models representing a deep curve of Spee were created using cone-beam computed tomography (CBCT) data. The setup employed 0.022 × 0.028-inch zero-prescription brackets secured with elastomeric ligatures. …

Respiratory Recovery Via Endogenous And Electrical Stimulation-Induced Mechanisms Following Cervical Spinal Cord Injury, Taylor C. Holmes

Dissertations (1934 -)

Breathing is a complex neuromuscular behavior vital for the maintenance of life. Cervical spinal cord injury (cSCI) disrupts descending respiratory motor drive and can lead to profound breathing impairments. While a limited, endogenous recovery of respiratory function has been well described following cSCI, this work has predominantly utilized single sex investigations. Given that relatively few treatment options exist to address this respiratory insufficiency, a more complete characterization of respiratory recovery post-cSCI is necessary for the development and evaluation of rehabilitative protocols. Diaphragm pacing (DP) is an emerging clinical intervention that utilizes electrical stimulation of the diaphragm muscle to combat the …

Graph Convolutional Networks Enable Fast Hemorrhagic Stroke Monitoring With Electrical Impedance Tomography, J. Toivanen, V. Kolehmainen, A. Paldanius, A. Hänninen, A. Hauptmann, Sarah J. Hamilton

Mathematical and Statistical Science Faculty Research and Publications

Objective: To develop a fast image reconstruction method for stroke monitoring with electrical impedance tomography with image quality comparable to computationally expensive nonlinear model-based methods. Methods: A post-processing approach with graph convolutional networks is employed. Utilizing the flexibility of the graph setting, a graph U-net is trained on linear difference reconstructions from 2D simulated stroke data and applied to fully 3D images from realistic simulated and experimental data. An additional network, trained on 3D vs. 2D images, is also considered for comparison. Results: Post-processing the linear difference reconstructions through the graph U-net significantly improved the image quality, resulting in images …

Advances In Noninvasive Imaging For Detecting Radiation-Induced Lung Injury (Rili), Austen Nissen, Said H. Audi, Anne V. Clough, Brian Fish, Amit Joshi, Meetha Medhora, Jason Walter Sidabras, Heather A. Himburg

Biomedical Engineering Faculty Research and Publications

Purpose: Dr. Richard Hill performed pioneering work in the field of radiation-induced normal tissue injury to the lung including noninvasive imaging studies aimed at identifying imaging biomarkers of radiation-induced lung injury (RILI). RILI is a life-threatening toxicity of radiation exposure relevant to both cancer patients undergoing thoracic radiation therapy (RT) and victims of accidental radiation exposure. The ability to detect RILI noninvasively has the potential to guide treatment planning for RT and, in the case of victims of acute radiation exposures, inform the decision to start mitigative therapies. As part of this special issue of IJRB honoring Dr. Hill’s many …

Quality Of Life Outcomes Following Total Temporomandibular Joint Replacement: A Systematic Review Of Long-Term Efficacy, Functional Improvements, And Complication Rates Across Prosthesis Types, Luis Eduardo Almeida, Samuel Zammuto, Louis G. Mercuri

School of Dentistry Faculty Research and Publications

Introduction:

Total temporomandibular joint replacement (TMJR) is a well-established surgical solution for patients with severe TMJ disorders. It aims to relieve chronic pain, restore jaw mobility, and significantly enhance quality of life. This systematic review evaluates QoL outcomes following TMJR, analyzes complication profiles, compares custom versus stock prostheses, explores pediatric applications, and highlights technological innovations shaping the future of TMJ reconstruction.

Methods:

A systematic search of PubMed, Embase, and the Cochrane Library was conducted throughout April 2025 in accordance with PRISMA 2020 guidelines. Sixty-four studies were included, comprising 2387 patients. Results: Primary outcomes assessed were QoL improvement, pain reduction, and …

Designing A Portable And Accessible Diffuse Reflectance Spectroscopy System For Real-Time Detection Of Cervical Intraepithelial Neoplasia, Allison Scarbrough, Diana Moses, Tongtong Lu, Bing Yu

Biomedical Engineering Faculty Research and Publications

Significance: Over 80% of cervical cancer cases occur in lower-to-middle income countries (LMIC’s). This is partly because current screening techniques lack affordability, accessibility, and/or reliability for use in LMIC’s.

Aim: To develop an optical technique for cervical cancer screening that is affordable, accessible, and reliable for use in LMIC’s.

Approach: We developed a portable diffuse reflectance spectroscopy (DRS) system, which costs < $2500 USD to manufacture, and employs a Raspberry Pi to extract the absorption (μ_a) and reduced scattering (μ'_s) coefficients of biological tissue. The system was subject to travel and intentional rough handling. It was further used to capture 320 DRS spectra taken from 64 tissue-mimicking phantoms. Two …

Lianas Reduce Tree Height With Negative Consequences For Carbon Storage And Growth Estimates, Xingyan Cao, Frieke Van Coillie, Sruthi M. Krishna Moorthy, Kasper Coppieters, Barbara D'Hont, Stefan A. Schnitzer, Geertje M. F. Van Der Heijden, Hans Verbeeck, Félicien Meunier

Biological Sciences Faculty Research and Publications

1. Current evidence suggests that liana (woody vine) competition with trees could be threatening the carbon sink by reducing carbon uptake and storage in tropical forests. Previous studies investigating forest demography in liana removal experiments have, however, assumed similar allometries for trees, regardless of the amount of lianas they support. Yet, recent observations suggest that liana load may alter tree shape and structure, including height, which could result in an underestimation of the liana effects on forest carbon stocks and tree growth.
2. In this study, we used terrestrial laser scanning (TLS) in a liana removal experiment in Gigante Peninsula, Panama, collected …

The State Of The Science Of Natural Family Planning: A Report From Nfp Scientists’ Meeting Held In Orlando, Fl, September 4, 2024, Michael D. Manhart, Richard J. Fehring

College of Nursing Faculty Research and Publications

A one-day meeting was held as a pre-conference to the Catholic Medical Association Annual Educational event in 2024. A panel of eighteen physicians, scientists, and researchers involved in NFP work was convened to review the available evidence in four topical areas: (i) evidence for effectiveness of NFP methods to postpone and achieve pregnancy, (ii) evidence for effectiveness in the postpartum and perimenopause transition periods, (iii) evaluate the current state of technology in NFP (specifically app and quantitative hormone monitoring), and (iv) evidence examining the impact of NFP on marital relations. In each topical area, the panel worked to reach a …

Review Of Viri Dignitatem: Personhood, Masculinity, And Fatherhood In The Thought Of John Paul Ii, Christine Falk Dalessio

Theology Faculty Research and Publications

No abstract provided.

Magnetospectroscopic Studies Of A Series Of Fe (Ii) Scorpionate Complexes: Assessing The Relationship Between Halide Identity And Zero-Field Splitting, Daniel J. Santalucia, Laxmi Devkota, Sergey V. Lindeman, Andrew Ozarowski, J. Krzystek, Mykhaylo Ozerov, Samuel M. Greer, Daniel C. Cummins, Klaus H. Theopold, Mihail Atanasov, Joshua Telser, Adam T. Fiedler

Chemistry Faculty Research and Publications

Ferrous ions in four-coordinate environments are common in protein structures, synthetic catalysts, and molecular magnets. The 3d⁶ configuration of high-spin Fe­(II) imparts an S = 2 ground state, whose analysis using conventional spectroscopic methods is often hindered by substantial zero-field splitting (ZFS). Herein, we provide detailed electronic-structure descriptions for [Fe^IIX­(Tp^tBu,Me)] (1-X; X = F, Cl, Br, I), where (Tp^tBu,Me)⁻ is hydrotris­(3-tert-butyl-5-methyl-pyrazol-1-yl)­borate. The three pyrazolyl N-donors of the “scorpionate” ligand facially coordinate to Fe­(II), giving idealized C_3v symmetry with the halide occupying the axial position. Although originally …

Novel Respirometry Measurement And Comparison Of Monod Kinetic Constants And Methanogen Concentrations For 27 Full-Scale Anaerobic Bioreactors, Nicholas Benn, Antonio Martins, Daniel H. Zitomer

Civil and Environmental Engineering Faculty Research and Publications

Monod kinetic coefficient values (km and Ks) as well as methanogen concentrations (Xac and Xh2) for various anaerobic bioreactors are required to gain a deeper understanding of anaerobic biotechnology. However, there are no existing, practical methods to measure or estimate these parameters or variables in typical anaerobic digester biomass that contains mixed cultures with inert organic solids. Current measurement methods rely on pure cultures developed in the laboratory. In this work, a novel respirometric method was developed and used to determine methanogen Monod parameters and active biomass concentration for samples from 27 full-scale anaerobic reactors. Differences (one to three orders …

Sex-Based Differences In The Representation Of Top Youth Athletes, Jessica J. James, Sandra K. Hunter, Elizabeth P. Bueckers, Michael J. Joyner, Jonathon W. Senefeld

Exercise Science Faculty Research and Publications

Although emerging research demonstrates that male athletes outperform female athletes before puberty, the effect of these sex-related advantages on ordinal ranking of top performances remains unclear.

Objectives

Among overall top performances of youth track and swimming athletes, we aimed to determine 1) the proportional number of male compared with female athletes represented and 2) at what age females are no longer represented.

Methods

Finishing times and sex of the top 10 and top 100 performances of youth runners and swimmers between 5 and 18 yr were abstracted from online U.S.-based databases for four running (100 m–800 m) and six freestyle …

Assessing The Relationship Of Cultural Values, And Neighborhood Factors In Prenatal Depression Amongst Mexican Women, Esmeralda Lezama Ruiz

Master's Theses (2009 -)

Maternal depression during the perinatal period is a debilitating illness which negatively influences maternal health, child development and family functioning. The rate of maternal depression in Mexican-American mothers is substantially higher than non-Hispanic white populations. Some work has linked maternal depression in the US Mexican population to cultural factors and neighborhood dynamics, but these factors are only beginning to be addressed in perinatal mental health. This study investigates the independent and interactive roles of cultural values and neighborhood factors in predicting perinatal maternal depressive symptoms in women of Mexican descent. The study recruited pregnant women (N= 261) of Mexican descent …

Periodontal Diseases In Africa, Mojisola Olujitan, Patricia O. Ayanbadejo, Kehinde Umeizudike, Afolabi Oyapero, Christopher Okunseri, Azeez Butali

School of Dentistry Faculty Research and Publications

Periodontal diseases, a group of complex conditions marked by an excessive immune response and periodontal tissue destruction, are a global health concern. Since 1990, the incidence of these diseases has doubled, with Western sub-Saharan Africa experiencing the highest burden. Accurate diagnosis and case identification are crucial for understanding the etiology, features of disease, research, treatment and prevention. Modern perspectives on periodontal disease classification are based on commonality among those affected. However, current literature is often plagued by methodological inconsistencies and focused on disease mechanisms in European populations. Health inequalities in low- and middle-income countries (LMICs) are exacerbated by these challenges, …

Ensuring Integrity In Dental Education: Developing A Novel Ai Model For Consistent And Traceable Image Analysis In Preclinical Endodontic Procedures, Mohamed Ibrahim, Meisam Omidi, Arndt Guentsch, Joseph Gaffney, Jennifer Talley

School of Dentistry Faculty Research and Publications

Aim

Academic integrity is crucial in dental education, especially during practical exams assessing competencies. Traditional oversight may not detect sophisticated academic dishonesty methods like radiograph substitution or tampering. This study aimed to develop and evaluate a novel artificial intelligence (AI) model utilizing a Siamese neural network to detect inconsistencies in radiographic images taken for root canal treatment (RCT) procedures in preclinical endodontic courses, thereby enhancing educational integrity.

Methododology

A Siamese neural network was designed to compare radiographs from different RCT procedures. The model was trained on 3390 radiographs, with data augmentation applied to improve generalizability. The dataset was split into …

Understanding Parents’ Beliefs About The Etiology Of Youth Mental Health Problems: Differences Across Race/Ethnicity, Madeline Buchanan, Lindsay E. Holly

Psychology Faculty Research and Publications

Parents’ etiological explanations for youth mental health problems are relatively understudied; most studies focus on adult beliefs about the causes of mental disorders experienced by adults. This is concerning given research demonstrating that parents’ causal beliefs may influence several aspects of youth mental health service utilization including whether parents seek help for their youth and how they engage in treatment. The current study used a novel methodology to examine causal beliefs about youth mental health problems among a diverse group of parents (N = 417; 36.9% non-Hispanic White; 33.3% Black/African American; 29.8% Hispanic/Latino) who completed a series of questionnaires …

Understanding Intergenerational Trauma Among Arab, Middle Eastern, And North African (Arab/Mena) Americans, Rawan H. Atari-Khan, Nuha Alshabani, S. Dolma Rabgay, Farida Refaat Elhedk, Ava Clifford, Sofia Gomariz, Warda Sahib

Psychology Faculty Research and Publications

Arab, Middle Eastern, and North African Americans experience various forms of racial–ethnic trauma in the United States, including historical and intergenerational trauma (IGT). The population has been migrating to the United States since the 1800s, and the number of migrants has risen in recent decades due to war, persecution, and family reunification. As a result, the children of these migrants may be exposed to IGT, with research suggesting that descendants of individuals who have experienced trauma are more susceptible to poor mental health outcomes. Using semistructured interviews, alongside the art of storytelling and empowerment through critical consciousness, this study investigated …

A Developmental Texture Framework For Food Texture Progression: Implications For Feeding Development, Oral Motor Skills, And Pediatric Feeding Disorder, Amy L. Delaney, Sarah Staskiewicz, Suzanne Evans Morris, Sarah Smith-Simpson, Praveen S. Goday

Speech Pathology and Audiology Faculty Research and Publications

The introduction of food textures in a child's first 2 years of life plays a vital role in growth, nutrition, and feeding development. However, the absence of a standardized texture framework for studying texture progression limits both pediatric feeding research and the ability to diagnose pediatric feeding disorder (PFD) based on age-appropriate expectations. To address this gap, authors Delaney and Goday proposed data sharing from the Nestlé Feeding Infant-Toddler Study (FITS) to explore texture progression and define age-appropriate texture expectations. In response, Nestlé assembled a multidisciplinary panel of feeding experts to create standardized textures but did not provide financial or …

Evaluating Artificial Intelligence Chatbots For Patient Education In Oral And Maxillofacial Radiology, Dilek Helvacioglu-Yigit, Husniye Demirturk, Kamran Ali, Dania Tamimi, Lisa J. Koenig, Abeer Almashraqi

School of Dentistry Faculty Research and Publications

Objective

This study aimed to compare the quality and readability of the responses generated by 3 publicly available artificial intelligence (AI) chatbots in answering frequently asked questions (FAQs) related to Oral and Maxillofacial Radiology (OMR) to assess their suitability for patient education.

Study Design

Fifteen OMR-related questions were selected from professional patient information websites. These questions were posed to ChatGPT-3.5 by OpenAI, Gemini 1.5 Pro by Google, and Copilot by Microsoft to generate responses. Three board-certified OMR specialists evaluated the responses regarding scientific adequacy, ease of understanding, and overall reader satisfaction. Readability was assessed using the Flesch-Kincaid Grade Level (FKGL) …

Predicting Seizure Onset Zones From Interictal Intracranial Eeg Using Functional Connectivity And Machine Learning, Jared Pilet, Scott A. Beardsley, Chad Carlson, Christopher T. Anderson, Candida Ustine, Sean Lew, Wade Mueller, Manoj Raghavan

Biomedical Engineering Faculty Research and Publications

Functional connectivity (FC) analyses of intracranial EEG (iEEG) signals can potentially improve the mapping of epileptic networks in drug-resistant focal epilepsy. However, it remains unclear whether FC-based metrics provide additional value beyond established epilepsy biomarkers such as epileptic spikes and high-frequency oscillations (HFOs). Using interictal iEEG data from 26 patients, we estimated FC across eight frequency bands (4–290 Hz) using amplitude envelope correlation (AEC) and phase locking value (PLV). From the resulting FC-matrices, we estimated two graph metrics each to derive 32 FC-based features. We also extracted features related to spikes, HFOs, and power spectral densities (PSD). A trained support …

Comparison Of Hand-Wrist And Cvms Methods For Craniofacial Growth Spurt Assessment, Ardita Ajvazi

Master's Theses (2009 -)

Objective: Hand-wrist (HW) radiographs are considered the most accurate method for assessing pubertal growth spurts in orthodontics but have declined in use due to added radiation exposure and the expertise required. Cervical vertebral maturation staging (CVMS) is now commonly used, given the routine availability of lateral cephalograms. However, the validity of CVMS remains uncertain. A recent study reported only 66% inter-observer reliability across time periods (Ingersoll, 2024). This follow-up study aims to evaluate CVMS as a predictor of growth to guide clinical decision-making. Methods: With protocol approval (MU HR-4695), this retrospective study followed a design modeled after a prior study …

Hsp70 Chaperones, Ssa1 And Ssa2, Limit Poly(A) Binding Protein Aggregation, Hannah E. Buchholz, Sean A. Martin, Jane E. Dorweiler, Claire M. Radtke, Adam S. Knier, Natalia B. Beans, Anita L. Manogaran

Biological Sciences Faculty Research and Publications

Molecular chaperones play a central role in maintaining protein homeostasis. The highly conserved Hsp70 family of chaperones have major functions in folding of nascent peptides, protein refolding, and protein aggregate disassembly. In yeast, loss of two Hsp70 proteins, Ssa1 and Ssa2, is associated with decreased cellular growth and shortened lifespan. While heterologous or mutant temperature-sensitive proteins form anomalous large cytoplasmic inclusions in ssa1Δssa2Δ strains, it is unclear how endogenous wild-type proteins behave and are regulated in the presence of limiting Hsp70s. Using the wild-type yeast Poly A binding protein (Pab1), which is involved in mRNA binding and forms stress granules …

Peroxi-Electrocoagulation For Pfas Mitigation: The Impact Of Water Quality And Dissolved Organic Matter On Removal Pathways, Donald R. Ryan, Claire K. Baldus, Shimaa M. Kteeba, Melvin Samuel, Yin Wang, Laodong Wang, Brooke K. Mayer, Patrick J. Mcnamara

Civil and Environmental Engineering Faculty Research and Publications

The recent addition of per- and polyfluoroalkyl substances (PFAS) to the National Primary Drinking Water Regulation per- has increased the need for research on PFAS treatment technologies for water and wastewater. Electrochemical treatment processes have been widely investigated for PFAS removal. Peroxi-electrocoagulation (electrocoagulation paired with hydrogen peroxide (EC:H₂O₂)) was evaluated as a novel water treatment process for PFAS mitigation due to the multimechanistic removal pathways that can proceed during treatment, including chemical degradation via oxidation, and physical separation pathways such as sorption to flocs, flotation layer accumulation, and foam fractionation. This work investigated the impacts of …

Efficient Fully Bayesian Approach To Brain Activity Mapping With Complex-Valued Fmri Data, Zhengxin Wang, Daniel B. Rowe, Xinyi Li, D. Andrew Brown

Mathematical and Statistical Science Faculty Research and Publications

Functional magnetic resonance imaging (fMRI) enables indirect detection of brain activity changes via the blood-oxygen-level-dependent (BOLD) signal. Conventional analysis methods mainly rely on the real-valued magnitude of these signals. In contrast, research suggests that analyzing both real and imaginary components of the complex-valued fMRI (cv-fMRI) signal provides a more holistic approach that can increase power to detect neuronal activation. We propose a fully Bayesian model for brain activity mapping with cv-fMRI data. Our model accommodates temporal and spatial dynamics. Additionally, we propose a computationally efficient sampling algorithm, which enhances processing speed through image partitioning. Our approach is shown to be …

Locked Dimerized Cxcl12 Exerts Radiosensitizing Effects In Head And Neck Cancer, Oscar Villarreal Espinosa, Musaddiq Awan, Abdullah A. Memon, Anne Frei, Jamie Foeckler, Rachel Kuehn, Jennifer Bruening, Becky Massey, Stuart J. Wong, Monica Shukla, Julia Kasprzak, Amit Joshi, Michael B. Dwinell, Heather A. Himburg, Joseph Zenga

Biomedical Engineering Faculty Research and Publications

Background

Head and neck squamous cell carcinoma (HNSCC) presents significant treatment challenges, particularly in cases unrelated to human papillomavirus (HPV). The chemokine receptor CXCR4, interacting with its ligand CXCL12, plays a crucial role in tumor proliferation, metastasis, and treatment resistance. This study explores the therapeutic potential of engineered monomeric and dimerized CXCL12 variants (CXCL121 and CXCL122, respectively) in HNSCC and evaluates potential additive effects when combined with radiation therapy.

Methods

Clinical HNSCC biopsies were evaluated for CXCR4 expression in both previously untreated and radiorecurrent disease. HNSCC cell lines were then treated with combinations of CXCL12 variants and radiotherapy and interrogated …

Influence Of Boundary Conditions And Blood Rheology On Indices Of Wall Shear Stress From Ivus-Based Patient-Specific Stented Coronary Artery Simulations, R. Patrick Mccarthy, Peter J. Mason, David S. Marks, John F. Ladisa Jr.

Biomedical Engineering Faculty Research and Publications

The long-term clinical efficacy of coronary stents is limited by restenosis. Coronary stenting results in altered arterial geometry, local blood flow patterns, and wall shear stress (WSS), all of which can influence restenosis. Computational fluid dynamics (CFD) simulations employ assumptions about blood properties and boundary conditions, which also influence WSS alterations from stenting. Our objective was to evaluate three common assumptions applied with stented coronary artery CFD simulations (inlet velocity profile, outlet boundary conditions, and viscosity) to provide insight for future studies. A patient-specific right coronary artery was reconstructed from intravascular ultrasound and computed tomography imaging. Time-averaged WSS (TAWSS) and …

Involvement Of Long Non-Coding Rna (Lncrna) Malat1 In Shear Stress Regulated Adipocyte Differentiation, Justin Caron, Marjan Ghanbariabdolmaleki, Madison Marino, Chong Qiu, Bo Wang, Michael Mak, Shue Wang

Biomedical Engineering Faculty Research and Publications

Adipocyte differentiation plays an important role in bone remodeling due to secretory factors that can directly modulate osteoblast and osteoclast, thus affecting overall bone mass and skeletal integrity. Excessive adipocyte differentiation within the bone marrow microenvironment can lead to decreased bone mass, eventually causing osteoporosis. The mechanical microenvironment of bone marrow, including fluid shear, maintains the balance of adipocyte and osteoblast differentiation during bone remodeling. However, how mechanical cues interact with long noncoding RNA (lncRNA) and regulate adipocyte differentiation remains unexplored. In this study, we investigated the mechanosensitive role of lncRNA MALAT1 during mesenchymal stem cells (MSCs) adipocyte differentiation. By …

Effects Of Soluble Electron Shuttles On Microbial Iron Reduction And Methanogenesis, Bhim Sen Thapa, Theodore M. Flynn, Zena D. Jensvold, Kenneth M. Kemner, Margaret F. Sladek, Edward J. O'Loughlin, Christopher W. Marshall

Biological Sciences Faculty Research and Publications

In many aquatic and terrestrial ecosystems, iron (Fe) reduction by microorganisms is a key part of biogeochemical cycling and energy flux. The presence of redox-active electron shuttles in the environment potentially enables a phylogenetically diverse group of microbes to use insoluble iron as a terminal electron acceptor. We investigated the impact that different electron shuttles had on respiration, microbial physiology, and microbial ecology. We tested eight different electron shuttles, seven quinones and riboflavin, with redox potentials between 0.217 and −0.340 V. Fe(III) reduction coupled with acetate oxidation was observed with all shuttles. Once Fe(III) reduction began to plateau, a rapid …