Physiology Commons^™

Electromyography, Prosthetic Properties, And Running Biomechanics In Recreationally Active Persons With Lower Extremity Amputation, Paige M. Agnew

Rehabilitation Sciences Theses & Dissertations

Lower extremity loss affects nearly 150,000 individuals in the United States yearly yielding extreme health care costs annually. Typically, prosthetic devices are prescribed for 5-8 years despite known changes to an individual’s gait as time progresses. Patients can expect to undergo approximately 8-12 weeks of gait retraining to improve their comfort and efficiency. Biomechanical changes occur when running with a specific running prosthetic including considerable biomechanical and neuromuscular interlimb asymmetries and alterations in loading patterns. The purpose of this dissertation was to investigate the biomechanical demands for lower extremity prosthesis users during running. The first study synthesized peer reviewed evidence …

Predator-Prey Responses Of The Clamworm Alitta Succinea To Direct Interaction With Crabs And Chemical Cues, Shyann Mcclain, Gloria M. Massamba N'Siala

Knowledge and Creativity Expo

Predator–prey interactions in marine benthic systems can have important indirect effects mediated through environmental signaling. Predators can reveal their presence through the release of chemical cues, influencing the activity and feeding rates of other potential prey through non-consumptive effects, which may ultimately shape energy allocation and survival in targeted populations. Along the Atlantic coast of the United States, predatory crabs overlap spatially with polychaete prey such as the clamworm Alitta succinea, creating consistent predation pressure. This study will set up the experimental system needed to examine the physiological responses of clamworms to both direct and indirect predation cues under controlled …

Establishing Aquarium Systems And Care Protocols For Marine Invertebrates In The Department Of Biological Sciences At Odu, Magdalene R. Hamlin, Gloria Massamba N'Siala Ph.D.

Knowledge and Creativity Expo

Maintaining live animals in lab settings is useful for establishing a stock of specimens available for experimental studies without relying on continuous collection efforts. Previous aquarium systems utilized in the aquatic facility of the Department of Biological Sciences at ODU were suited for research on freshwater and marine vertebrates and were not designed for the care of marine invertebrates. This project aims to establish methods and protocols suitable for maintaining various marine invertebrates in a control laboratory setting. In the first stage of the project, the existing recirculation system and lab space will be reorganized and restructured to suit the …

Chronobiology Of Meal Timing In Early-Stage Hypertension: A Controlled Feeding Pilot Study Investigating The Effects On Renal And Vascular Function, Natalie J. Bohmke, Brittany Barton, Patrice Wiecek, Paula Rodriguez-Miguelez, Dave L. Dixon, Youngdeok Kim, Salvatore Carbone, Danielle L. Kirkman

EVMS School of Health Professions Faculty Publications

Lifestyle intervention is critical for young adults with early-stage hypertension. A Western diet has negative effects on kidney function and blood pressure; however, time-of-day effects are understudied. We hypothesized that consumption of a Western-style meal that is misaligned with the endogenous circadian rhythm would have adverse effects on blood pressure, kidney function, and vascular function. Ten young adults with elevated blood pressure or stage 1 hypertension (means ± SD: 26 ± 8 yr, 50% female) underwent a randomized crossover, isocaloric controlled feeding intervention. Participants were allocated to receive a Western-style meal high in sodium, sugar, and saturated fat in the …

Educational Case: Hidradenitis Suppurativa, Ryan C. Saal, Linnea Lackstrom Westerkam, Cristo A. Carrasco Mendoza, Paul B. George, Christopher J. Sayed

Department of Medicine Faculty Publications

[Introduction] The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see https://doi.org/10.1016/j.acpath.2023.100086.1¹

Objective SK1.1: Pathophysiology of changes in the skin. Describe the pathophysiologic basis for changes in the color, surface texture, swelling, temperature, and sensitivity of skin.

Competency 2: Organ system pathology, Topic: Skin (SK); Learning Goal 1: …

Metabolic Reprogramming Following Mitochondrial Transfer Between Idh2-Mutant Chondrosarcoma Cells And A Normal B-Cell Line, Caleb Wyckoff, Christopher Osgood, Ellen Jing, Michael Stacey

Bioelectrics Publications

Background/Objectives: Chondrosarcoma, glioblastoma, acute myeloid leukemia, chronic lymphocytic leukemia, and cholangiocarcinoma cancers all contain mutations in the gene isocitrate dehydrogenase 2 (IDH2). The mutant IDH2 enzyme metabolizes alpha-ketoglutarate (αKG) into the potent oncometabolite D-2-hydroxyglutarate (D2HG) in the mitochondria of these cancers, leading to altered cellular metabolism. Emerging evidence suggests that mitochondrial transfer between cancer and recipient cells represents an important form of intercellular communication that may influence cellular metabolism. The presence of intercellular TNTs between IDH2-mutant chondrosarcoma cells motivated an investigation into mitochondria-associated physiological changes occurring during an intercellular exchange with immune cells. A mitochondrial transfer is a two-way …

Pilot Study On The Use Of Multimorbidity Index In Patients Receiving Home Parenteral Nutrition, Michael M. Rothkopf, Mohan Pant, Zachary Rothkopf, Rebecca Brown Rdn, Jaime Haselhorst Rdn, Debbie L. Stevenson Rdn, Andrew Depalma Mba, Michael Saracco

Epidemiology, Biostatistics, & Environmental Health Faculty Publications

Background

Home parenteral nutrition (HPN) patients often have multiple comorbidities. A validated multimorbidity index (MMI) could help determine resource needs and risks with HPN. We evaluated MMI scoring to determine if it predicted HPN resource use and outcomes.

Methods

We performed a secondary analysis of 60 HPN patients from a previous study based on Cumulative Illness Rating Scale (CIRS) scoring. We examined three variables: PN formula changes, hospitalizations, and hospital length of stay (LOS). Density plots were produced to select a CIRS score cutoff value. Spearman correlations among the three variables of interest were computed. The data were then subjected …

Severity And Duration-Dependent Aortic Stiffening In A Rabbit Coarctation Model Identifies Constitutive Material Parameters As Promising Regional Biomarkers For Hypertension Progression, Arash Ghorbannia, Jamasp Azarnoosh, John F. Ladisa Jr.

VMASC Publications

Coarctation of the aorta (CoA) alters hemodynamics and drives regional remodeling, yet the influence of severity and duration on constitutive properties is undefined. We quantified mechanical responses from CoA to identify constitutive parameters capturing stiffening across clinical severities and durations. Mild (≤ 12 mmHg), intermediate (13–20 mmHg), and severe (> 20 mmHg) CoA was created in rabbits for short, long, and prolonged durations (~ 1, 3, or 22 weeks, respectively). Stress–stretch curves from proximal and distal regions were fit with multiple constitutive models (Linear Elastic, Neo-Hookean, Yeoh, Ogden, Mooney–Rivlin, Holzapfel). Model performance was evaluated by normalized RMSE and R², with …

Eeg And Imu Gait Signal Processing: A Comparative Assessment Of The "Reza" Exponential Filter And Classic Filters, Reza Pousti, Daniel M. Russell, Derek C. Monroe, Christopher K. Rhea

Rehabilitation Sciences Faculty Publications

Noise degrades both EEG and gait signals, and classical IIR filters (Butterworth, Chebyshev, elliptic) involve trade-offs between passband flatness, ripple, and roll-off. This study compared a novel exponential "Reza" filter with these designs for neural and locomotor data. We analyzed an open-source mobile brain-body imaging dataset with EEG and gait data from 49 healthy adults (EEG: 256-channel, 512 Hz; IMUs: six APDM Opals, 128 Hz). EEG channels were grand-averaged and band-pass filtered at 0.5-50 Hz, while IMU axes were averaged and band-pass filtered at 0.5-5 Hz. The outcomes were signal-to-noise ratio SNR (dB) and band-integrated Welch PSD (EEG:0.5-50 Hz; IMU:0.5-5 …

The Sequence (S) Index As A Marker Of Diminished Step-To-Step Transition Efficiency In Older Adults, Elham Alijanpour, Ashwini Kulkarni, Peter G. Adamczyk, Daniel M. Russell

Rehabilitation Sciences Faculty Publications

Introduction: Age-related declines in walking efficiency are often attributed to musculoskeletal and neuromuscular changes, yet the mechanisms underlying these inefficiencies remain poorly understood. One key contributor is the step-to-step transition (STST), during which the center of mass (CoM) is redirected between limbs. The Sequence (S) index quantifies the temporal overlap between push-off and collision forces during STST, with higher values indicating greater mechanical energy loss. This study investigated whether aging affects STST efficiency, as quantified by the S index, and examined the timing and impulse characteristics underlying observed differences.

Methods: Thirteen young and eleven older healthy adults walked at five …

Ultrasound-Based Assessment Of Talar Cartilage In Individuals With Chronic Ankle Instability: A Systematic Review, Amin Mohammadi, Saeed Eshghi, Iman Mohammadi, Patrick Wilson, Ryan Mccann

Rehabilitation Sciences Faculty Publications

Purpose

To systematically synthesize ultrasound (US) evidence on talar cartilage morphology and load-induced deformation in individuals with chronic ankle instability (CAI), and to map methodological approaches (acquisition, outcome definitions, loading paradigms, and normalization) to inform protocol standardization.

Methods

PubMed, Web of Science, and EBSCO were searched (March 31, 2025). Eligible studies reported quantitative US-derived talar cartilage morphology (e.g., thickness, cross-sectional area [CSA]) and/or deformation following standardized loading in CAI and comparison groups. Due to heterogeneity in imaging protocols, loading tasks, and outcome definitions, findings were synthesized narratively and organized by outcome domain.

Results

Across available cohorts, load-induced deformation was the …

Multisystem Predictors Of Dynamic Gait Stability Across Fall Risk In Older Adults, Ashwini Kulkarni, Neda Moghim, Ross Gore, Soumya Banerjee, Christopher K. Rhea, Brittany Samulski

Rehabilitation Sciences Faculty Publications

Gait stability arises from interactions between physiological, cognitive, and psychological systems, yet these domains are often assessed in isolation. This study examined multisystem predictors of anteroposterior margin of stability during walking (MoSAP) in community-dwelling older adults. Of 340 participants, 143 were retained after data quality screening (105 females; age: 70.8 ± 7.8 years). Participants completed the Physiological Profile Assessment (PPA), cognitive testing using Montreal Cognitive Assessment (MoCA), fear-of-falling evaluations using Modified Falls Efficacy Scale (MFES) and a biomechanical gait assessment during preferred and fast speeds. Participants were stratified into four PPA-based fall-risk groups: low, mild, moderate, and high risk. MoSAP …

Considerations For The Analysis Of Urinary Environmental Chemical Concentrations During Pregnancy, Danielle R. Stevens, Kaleigh Hinton, Katie M. O'Brien, Jessie P. Buckley, Barrett M. Welch, Jason A. Watts, Antonia M. Calafat, Julianne C. Botelho, Elena Sinkovskaya, Ann Przybylska, George Saade, Alfred Abuhamad, Kelly K. Ferguson

Department of Obstetrics & Gynecology Faculty Publications

Background:

Pregnancy physiology may impact indicators of hydration, affecting exposure assessment in gestational studies with urinary chemical biomarkers.

Methods:

We aimed to characterize hydration and demonstrate the impact of different methods for standardizing urinary chemical biomarker concentrations on exposure descriptives in the Human Placenta and Phthalates Study (n = 303, 2017-2020), a prospective pregnancy cohort with eight study visits between 12 and 38 weeks of gestation. We assessed trajectories and predictors of hydration using urine flow rate (UFR) and specific gravity (SG). Likewise, we examined trajectories and predictors of mono-n-butyl phthalate (MBP), for which concentrations were unstandardized or standardized via …

Feeding Mode Is Associated With Infant Night Sleep Trajectories During The First Postnatal Year, Magdalena Olson, Li Liu, Elizabeth Reifsnider, Dean V. Coonrod, Sarada S. Panchanathan, Megan E. Petrov, Corrie M. Whisner

Ellmer School of Nursing Faculty Publications

Background: Short sleep and formula feeding during infancy are associated with increased risk of childhood obesity. Feeding practices and sleep arrangements vary during infancy and may also be dynamic, yet their impact on infant night sleep duration remains unclear. Understanding these relationships is crucial for formulating recommendations to support breastfeeding and address sleep concerns. Objective: We examined the association between feeding mode and parent-reported infant night sleep duration during the first postnatal year, while additionally evaluating night-weaning and bedsharing as contextual sleep-related practices. Methods: Infants in the Phoenix Metropolitan Area (n = 193) were followed up at 3, 8, 13, …

Estrogen Deprivation During Primate (Papio Anubis) Pregnancy: Impact On Systemic Microvascular Flow And Cardiovascular Development And Function After Birth In Offspring, Sifa Turan, Jeffery S. Babischkin, Graham W. Aberdeen, Gerald J. Pepe, Eugene D. Albrecht

Department of Biomedical and Translational Sciences Faculty Publications

Background

Suppressing estradiol (E₂) during baboon pregnancy lowers offspring skeletal muscle capillary density, vital for insulin-mediated glucose uptake, and induces insulin resistance. We examined whether E₂ deprivation also impairs microvascular flow and cardiac function.

Methods

Offspring of untreated baboons, letrozole-treated baboons, or letrozole plus E₂ (maternal s.c. injections during the second half of gestation) underwent contrast-enhanced microbubble ultrasonography to quantify microvessel flow and echocardiography to assess cardiac performance.

Results

Letrozole reduced maternal serum E₂ by 95% (p <  0.01). In letrozole offspring, microbubble flux rate (β) fell 55% (p <  0.02), replenishment was 5 s slower (p <  0.03), and microvessel flow declined 40% (p = 0.05); all were restored by added E₂. Indices of systolic (isovolumic contraction), diastolic (isovolumic relaxation), global performance (Tei index), and cardiac output were unchanged.

Conclusion

Prolonged gestational E₂ deprivation programs a reduction in microvascular flow without altering cardiac function; maternal E₂ prevents this, supporting E₂'s role in …

Comparative Mass Spectrometry Analysis Of High And Low Centrifugation Extracellular Vesicle (Ev) Pellets From Healthy Urine Following Tamm-Horsfall Protein Removal, Dana Bielopolski, Luca Musante, Henrik Molina, Douglas Barrows, Samantha Upson, Lifang Yang, Thomas Carrol, Jonathan N. Tobin, Rhonda G. Kost, U. Erdbrügger

Department of Biomedical and Translational Sciences Faculty Publications

Objectives

Urinary extracellular vesicles (uEVs) are potential biomarkers for renal physiology and disease. Their isolation is challenged by Tamm-Horsfall protein (THP) contamination, particularly in high-speed ultracentrifugation (P100) fractions. Low-speed (P20) fractions contain biologically relevant uEVs, yet their proteomic composition is underexplored. This study evaluates strategies for THP removal to optimize mass spectrometry analysis and characterizes P20 and P100 uEV proteomes and its combination in healthy urine.

Methods

Urine from a healthy volunteer was processed via sequential centrifugation at 21,200 g (P20) and 164,244 g (P100). THP removal was performed using low ionic strength buffer (P20) and size-exclusion chromatography (P100). Western …

Eeg Signatures Of Motor Development In Early Childhood: A Systematic Review, Sonia Khurana, Ashwini Kulkarni, Thomas C. Bulea, Hunter J. Bennett

Rehabilitation Sciences Faculty Publications

Background

Early identification of motor developmental disorders is limited due to lack of objective neural markers that characterize typical neurodevelopmental patterns. This systematic review interprets and synthesizes existing evidence to propose a framework of EEG signatures associated with motor development in children aged 0-5 years, which may help inform future benchmarks for early assessment and intervention.

Methods

Following PRISMA guidelines, we searched published and gray literature across five databases between 2000 and 2025 (registered protocol). Included studies examined EEG during task-based, resting-state, or sleep studies linked to motor milestones, task performance, or standardized motor assessments. Study quality was assessed using …

Evaluating The Mediating Role Of Gestational Phthalate And Replacement Biomarkers In The Associations Between Race/Ethnicity And Birthweight, Amir J. Lueth, Danielle R. Stevens, Sarahna A. Moyd, Elena Sinkovskaya, Ann Przybylska, Antonia M. Calafat, Julianne C. Botelho, George Saade, Alfred Abuhamad, Kelly K. Ferguson

Department of Obstetrics & Gynecology Faculty Publications

Background

Gestational exposure to phthalates is higher among non-Hispanic black (NHB) women than non-Hispanic white (NHW) women and may contribute to racial/ethnic differences in birthweight z-scores.

Objective

We aimed to investigate whether gestational phthalate and replacement biomarkers mediate the association between race/ethnicity and birthweight z-scores.

Methods

We analyzed data from 271 pregnancies in the Human Placenta and Phthalates study, a prospective cohort recruited from 2017 to 2020. Urinary phthalate metabolite concentrations were measured at up to eight time points during pregnancy and averaged to represent gestational exposure. Metabolites were grouped by parent compound. Linear regression models estimated associations in phthalate …

Thyroid Storm At Sea: A Case Report Of Algae-Induced Thyrotoxicosis, Alynna Knaub, Amanda Cecchini, John Janousek, Laura Strojny, Jairo Noreña, Zachary Pawlikowski

Department of Medicine Faculty Publications

Iodine-induced thyrotoxicosis (IIT), also known as the Jod-Basedow phenomenon, is a rare yet recognized cause of hyperthyroidism. While iodinated contrast is the most frequent trigger, iodine-rich supplements such as seaweed products or supplements can also precipitate thyrotoxicosis, particularly in individuals with prior chronic iodine deficiency or preexisting thyroid nodular disease. We present a case of thyroid storm following short-term ingestion of Irish sea moss as part of a “crash diet.” A 37-year-old woman with type 1 diabetes mellitus, well controlled on subcutaneous insulin therapy, presented with nausea and vomiting after 6 days of following a restrictive diet consisting solely of …

Circulating Biomarker Results From A Phase 2 Study Of Seralutinib In Pulmonary Arterial Hypertension, Robin Osterhout, Athénaïs Boucly, Raymond L. Benza, Richard N. Channick, Kelly M. Chin, Robert P. Frantz, Anna R. Hemnes, Luke S. Howard, Vallerie V. Mclaughlin, Olivier Sitbon, Jean-Luc Vachiéry, Rotham T. Zamanian, Richard Aranda, Matt Cravets, Zhaoqing Ding, Thao Duong-Verlé, David Mattola, Robert F. Roscigno, Ravikumar Sitapara, Lawrence S. Zisman, Jean-Marie Bruey, Hossein-Ardeschir Ghofrani

Department of Medicine Faculty Publications

[Introduction] To the Editor: Pulmonary arterial hypertension (PAH) is a progressive disease characterized by obstructive pulmonary arterial remodeling (1). Seralutinib, an investigational inhaled tyrosine kinase inhibitor, potently and selectively targets kinases relevant to PAH pathobiology including platelet-derived growth factor receptors (PDGFR) α and β, colony stimulating factor 1 receptor (CSF1R), and mast/stem cell growth factor receptor kit (c-KIT) (2). In preclinical models, seralutinib improved cardiopulmonary hemodynamics, reversed pulmonary vascular pathology and decreased right ventricular hypertrophy (3). In TORREY, a phase 2, multicenter, double-blind, randomized, placebo-controlled trial in PAH, seralutinib significantly reduced pulmonary vascular resistance (PVR) after 24 weeks with good …

Selenium And Liver Steatosis And Fibrosis: Opposing Direct And Steatosis-Mediated Associations In A Large Cohort, Neda Rehan, Jubilee Benedict, Rehan Qayyum

Department of Medicine Faculty Publications

Background and Aims

Epidemiologic studies have reported conflicting associations between selenium exposure and liver disease. Whether selenium exerts opposing direct and steatosis-mediated effects on liver fibrosis is unknown. To evaluate the associations of blood selenium with elastography-defined hepatic steatosis and fibrosis and to determine whether hepatic steatosis mediates the relationship between selenium and fibrosis.

Methods

We conducted a cross-sectional analysis of adults aged >= 18 years in NHANES 2017-2023. Hepatic steatosis was assessed using the controlled attenuation parameter (CAP) and fibrosis using liver stiffness measurement (LSM). Blood selenium was categorized into quartiles. Survey-weighted multivariable linear regression and structural equation modeling …

Markov Chain Wave Generative Adversarial Network For Bee Bioacoustic Signal Synthesis, Kumudu Samarappuli, Iman Ardekani, Mahsa Mohaghegh, Abdolhossein Sarrafzadeh

Electrical & Computer Engineering Faculty Publications

This paper presents a framework for synthesizing bee bioacoustic signals associated with hive events. While existing approaches like WaveGAN have shown promise in audio generation, they often fail to preserve the subtle temporal and spectral features of bioacoustic signals critical for event-specific classification. The proposed method, MCWaveGAN, extends WaveGAN with a Markov Chain refinement stage, producing synthetic signals that more closely match the distribution of real bioacoustic data. Experimental results show that this method captures signal characteristics more effectively than WaveGAN alone. Furthermore, when integrated into a classifier, synthesized signals improved hive status prediction accuracy. These results highlight the potential …

Micrornas Regulated By Pregnancy Target Antiviral And Cancer Immunity Overlapping With The Hiv Interactome, Paula F. T. Cezar-De-Mello, Jonathan M. Dreyfuss, Pai-Lien Chen, Hidemi Yamamoto, Xiaoming Gao, Hui Pan, Charles Morrison, Gustavo F. Doncel, Robert L. Barbieri, Raina N. Fichorova

CONRAD Publications

Innate immunity predictors of HIV-1 risk and pathogenesis vary with reproductive hormones, pregnancy, and lactation, yet the underlying mechanisms remain unclear. We hypothesized that pregnancy-associated physiological adaptations alter systemic microRNA (miRNA) expression, thereby regulating immunity, pathogenesis and susceptibility to infection. We analyzed 174 serum samples from 88 participants in a longitudinal cohort from Uganda and Zimbabwe across pre-pregnancy (PP), pregnancy (P), and postpartum breastfeeding (BF). Cell-free peripheral blood miRNAs (n = 2083) were profiled using HTG EdgeSeq. Pregnancy-specific miRNAs were identified by intersecting differentially expressed (DE) miRNAs from P vs. PP and P vs. BF comparisons. miRNA targets and pathways …

A Comprehensive Overview Of Neurophysiological Correlates Of Cognitive Impairment In Amyotrophic Lateral Sclerosis, Seyyed Bahram Borgheai, Brie E. Achorn, Alyssa H. Zisk, Sarah M. Hosni, Karl E. G. Richter, Frank S. Menniti, Yalda Shahriari

Computer Science Faculty Publications

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that leads to the gradual loss of motor control, typically resulting in paralysis and death within 3 to 5 years of diagnosis. ALS shares neuropathological and genetic associations with fronto-temporal dementia (FTD), a neurodegenerative condition primarily impacting cognitive functions. These two conditions are increasingly viewed as manifestations of a single molecular disease process that affects distinct brain systems, impacting motor neuronal pathways in ALS and fronto-cortical functions in FTD. However, this simple dichotomy belies the complexity of these conditions. In particular, patients with primary motor ALS can also experience significant cognitive …

Nadph Oxidase Isoforms (Nox-2 And Nox-4) In Myocardial Ischemia/Reperfusion Injury: Platelet Rich Plasma (Prp) As A Therapeutic Agent, Barbara Y. Hargrave, Frank Lattanzio

Cardiovascular Research Symposium

Introduction: Blood flow restoration to ischemic cardiac tissue is a critical and necessary intervention that has an associated downside: reperfusion injury. Reperfusion injury is a complicated process mediated in part by a pathological increase in reactive oxygen species (ROS). Although extremely elevated levels of ROS can cause cell damage, a minimum level of ROS is necessary for activation of Hydroxylated-HIF-1a (HIF-1a) and inhibition of Peroxisome Proliferator-Activated Receptor-alpha (PPARa) during myocardial ischemic reperfusion injury (MIRI). MIRI clinical manifestations include arrhythmias, myocardial stunning, decreased ventricular contractility and no-reflow. Platelet rich plasma (PRP) has improved left ventricular (LV) function after MIRI in …

The Impacts Of Physical (In)Activity On Endothelial Function, Joel Ernest Harden

Rehabilitation Sciences Theses & Dissertations

Exercise and physical activity are known to have beneficial effects on endothelial function and vascular health. Sedentary behavior and physical inactivity, however, have been shown to be related to poor endothelial function and vascular health. The overall purpose of this dissertation was to further elucidate the physiological links between physical (in)activity and vascular health. In the first study, 12 active, young (18-40 yr) individuals and 12 active, old (55+ yr) individuals were recruited. Participants underwent 5 days of removal of exercise, and had their endothelial function assessed via flow-mediated dilation (FMD) during their normal, habitual exercise state (EX) and during …

Organic Geochemical Evidence For Life In Archean Rocks Identified By Pyrolysis-Gc-Ms And Supervised Machine Learning, Michael L. Wong, Anirudh Prabhu, Conel O'D. Alexander, H. James Cleaves Ii, George D. Cody, Grethe Hystad, Marko Bermanec, Wouter Bleeker, C. Kevin Boyce, Andrea Corpolongo, Andrew D. Czaja, Souvik Das, Robert R. Gaines, Daniel D. Gregory, John A. Jaszczak, Emmanuelle J. Javaux, Jaganmoy Jodder, Andrew H. Knoll, Martin Van Kranendonk, Katie M. Maloney, Nora Noffke, Robert Rainbird, Emersyn Slaughter, Eva E. Stüeken, Roger E. Summons, Frances Westall, Jasmina Wiemann, Shuhai Xiao, Robert M. Hazen

OES Faculty Publications

Throughout Earth’s history, organic molecules from both abiogenic and biogenic sources have been buried in sedimentary rocks. Most of these organic molecules have been significantly altered by geologic processes through deep time. Nonetheless, the nature and distribution of those ancient fragmentary organic remains have the potential to reveal diagnostic biomolecular information after billions of years of burial. Here, we analyzed 406 fossil, modern biological, meteoritic, and synthetic samples using pyrolysis gas chromatography and mass spectrometry. We explored these analytical data via supervised machine-learning methods to discriminate samples of biogenic vs. abiogenic origin, plant vs. animal phylogenetic affinity, and photosynthetic vs. …

Traction Force Microscopy Using An Epifluorescence Microscope: Experimental Considerations And Caveats, Zaria Booth, Mazen Mezher, Rudra Patel, Venkat Maruthamuthu

Mechanical & Aerospace Engineering Faculty Publications

Forces exerted by cells due to their internal contractility play fundamental roles in a host of processes, including adhesion, migration, survival and differentiation. Traction force microscopy (TFM) enables the determination of forces exerted by cells or cell collectives on their environment, which is typically taken to be an extra-cellular matrix (ECM)-coated substrate. Sample preparation for TFM involves the plating of cells onto an environment embedded with fiducial markers. The imaging of these fiducial markers in the presence and absence of the cells then enables calculation of the displacement of localized regions of the environment, and, consequently, the spatial distribution of …

Impacts Of Physical Inactivity Models On Endothelial Function: A Systematic Review, Joel E. Harden, J. David Branch, Leryn J. Reynolds

Exercise Science Faculty Publications

Background

Endothelial dysfunction is associated with cardiovascular disease and cardiac events. Numerous studies demonstrate that a reduction in physical activity/exercise levels are associated with poor endothelial function. Yet, these studies use a plethora of models to mimic reduced activity levels which may have widely different results on endothelial function. It is pertinent to collectively review these articles to provide a comprehensive understanding of the impact of reduced activity on vascular health, as endothelial function is one of many factors that influences vascular tone.

Objective

The purpose of this systematic review is to examine and synthesize the current literature regarding the …

Motion Artifacts (Ma) At-Rest In Measured Arterial Pulse Signals: Time-Varying Amplitude In Each Harmonic And Non-Flat Harmonic-Ma Coupled Baseline, Md Mahfuzur Rahman, Mamun Hasan, Zhili Hao

Mechanical & Aerospace Engineering Faculty Publications

Motion artifacts (MA) cause great variability in a measured arterial pulse signal, and treatment of MA solely as a baseline drift (BD) fails to eliminate its effect on the measured signal. This paper presents a study on the effect of MA at rest (< 0.7 Hz) on measured arterial pulse signals using a microfluidic-based tactile sensor. By taking full account of the dynamic behavior of the transmission path from the true pulse signal in an artery to a measured pulse signal at the sensor, the tissue-contact-sensor (TCS) stack, an analytical model of MA in a measured pulse signal is developed. In this model, the TCS stack is treated as a 1DOF system for its dynamic behavior; MA is quantified as the displacement (i.e., BD) and time-varying system parameters (TVSP) of the TCS stack. The mathematical expression of MA in a measured pulse signal reveals that while BD remains as low-frequency additive noise, TVSP causes time-varying harmonics in a measured pulse signal. Further time-frequency analysis (TFA) of measured pulse signals validates the existence of TVSP and, for the first time, reveals its effect on a measured pulse signal: time-varying amplitude in each harmonic and non-flat harmonic-MA-coupled baseline.