Physiology Commons^™

A Decision-Space Model Explains Context-Specific Decision Making, Dirk W. Beck, Cory N. Heaton, Luis D. Davila, Lara I. Rakocevic, Sabrina M. Drammis, Danil Tyulmankov, Atanu Giri, Shreeya Umashankar Beck, Qingyang Zhang, Michael Pokojovy, Kenichiro Negishi, Alexis A. Salcido, Neftali F. Reyes, Andrea Y. Macias, Serina A. Batson, Paulina Vara, Raquel J. Ibáñez Alcalá, Safa B. Hossain, Graham L. Waller, Laura E. O'Dell, Travis M. Moschak, Ki A. Goosens, Alexander Friedman

Mathematics & Statistics Faculty Publications

Optimal decision-making requires consideration of internal and external contexts. Biased decision-making is a transdiagnostic symptom of neuropsychiatric disorders. We created a computational model demonstrating how the striosome compartment of the striatum constructs a context-dependent mathematical space for decision-making computations, and how the matrix compartment uses this space to define action value. The model explains multiple experimental results and unifies other theories like reward prediction error, roles of the direct versus indirect pathways, and roles of the striosome versus matrix, under one framework. We also found, through new analyses, that striosome and matrix neurons increase their synchrony during difficult tasks, caused …

Therapy-Based Strategies To Support Tummy Time In Infants Post-Hospital Discharge: A Scoping Review Protocol, Ketaki Inamdar, Sonia Khurana

Rehabilitation Sciences Faculty Publications

Tummy time is essential for infant development, yet many caregivers face significant challenges with adherence due to behavioral and contextual barriers. While numerous tummy time interventions exist, a limited understanding of their behavioral components hinders effective replication and implementation. This scoping review aims to identify multidisciplinary interventions used to promote tummy time in infants aged 0–12 months, evaluate their impact on adherence, developmental and health outcomes, and examine the behavior change techniques employed using the Theoretical Domains Framework (TDF). Following the Joanna Briggs Institute (JBI) methodology, a comprehensive search will be conducted in MEDLINE (PubMed), Web of Science Core Collection, …

Calculation Of Proton Transmembrane-Electrostatic Interaction Force And Elucidation Of The Water Droplet Experiment With A Transient Protonic Front, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

The “transmembrane-electrostatically localized proton(s)/cation(s) charge(s) (TELC(s), also known as TELP(s)) model” may serve as a theoretical framework to explain protonic cell energetics including both delocalized and localized protonic couplings. TELCs are held by their corresponding transmembrane-electrostatically localized hydroxides anions (TELAs) across the membrane through mutual transmembrane-electrostatic attractive force, which is now calculated to be in the range from 1.96 × 10⁻¹¹ to 2.28 × 10⁻¹¹ newtons (N) across a 2.5 nm thick membrane in a range of transmembrane potential from 10 to 200 mV. At a moderate transmembrane potential (100 mV), the protonic transmembrane attractive force is now calculated to …

Application Of Telc Model To Better Elucidate Neural Stimulation By Touch, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

Aim: This study is to better understand how the transient ion transport activity of touch receptors could change the graded potential to stimulate an action potential firing.

Methods: The latest transmembrane-electrostatically localized protons/cations charges (TELC) theory is employed for numerical analysis to calculate the neural touch signal transduction responding time required to fire an action potential spike.

Results: A neural action potential spike was constructed successfully using newly developed time-dependent TELC-based neural transmembrane potential integral equations (Equations 5, 6, and 7). The results explicated that the TELC curve has an inverse relationship with neural transmembrane potential since its curve appears …

Phytochemical Analysis, Antioxidant, And Antibacterial Properties Of Partition Fractions Of Adansonia Digitata And Annona Muricata Extracts Using Chloroform, Ethyl Acetate, Ethanol, And Aqueous Solvent Systems, Fagbohun Oyenike Bushirat, Hassan Abdusalam Adewuyi, Sakariyau Adio Waheed, Maryam Nana Musa, Timothy God-Giveth Olusegun, Ayomide Babatunde Ishola, Agumage Idoko, Adeola Victor Kolawole, Adesanmi Adefunmilayo Oluwatuyi, Sarah Ngozi Agwasim

Chemistry & Biochemistry Faculty Publications

Adansonia digitata and Annona muricata are traditionally used medicinal plants with reported pharmacological properties. In this study, we aimed to elucidate the phytochemical composition, antioxidant activity, and antibacterial properties of partition fractions of Adansonia digitata and Annona muricata extracts obtained using chloroform, ethyl acetate, ethanol, and aqueous solvent systems. The plant extracts were successively partitioned using chloroform, ethyl acetate, ethanol, and aqueous solvent systems. Phytochemical analysis was performed using standard methods. Antioxidant activity was evaluated using FRAP and DPPH assays. Antibacterial activity was assessed using agar well diffusion and MIC determination. Phytochemical analysis revealed the presence of alkaloids (10.2-15.6%), flavonoids …

Cellphone Separation Modulates The Effects Of Working Memory Load On Ex-Gaussian Parameters Of Choice Reaction Time, Michael Gazzanigo, Alexa Quesnel, Catalina Roldan, Xiao Yang

Psychology Faculty Publications

Cognitive effects of cellphone dependency among young adults have garnered increasing research attention. While cellphones have been identified as a distractor in daily tasks, related psychological processes remain unclear. As a potential mechanism underlying those effects of cellphones, excessive working memory (WM) load has not yet been well examined. Our study investigated the effects of the mental representation of cellphone separation on WM. Seventy-five participants (M(age) = 21.3 years; 55 females, 20 males) were assigned into three groups: the cued separation, natural separation, or control group, and completed a block of choice reaction time (CRT) task, and a dual-task block: …

Fiber Photometry Analysis Of Spontaneous Dopamine Signals: The Z-Scored Data Are Not The Data, Conner W. Wallace, Clare Y. Slinkard, Rachael Shaughnessy, Katherine M. Holleran, Samuel W. Centanni, Christopher C. Lapish, Sara R. Jones

Department of Medicine Faculty Publications

Fluorescent sensors have revolutionized the measurement of molecules in the brain, and the dLight dopamine sensor has been used extensively to examine reward- and cue-evoked dopamine release, but only recently has the field turned its attention to spontaneous release events. Analysis of spontaneous events typically requires evaluation of hundreds of events over minutes to hours, and the most common method of analysis, z-scoring, was not designed for this purpose. Here, we compare the accuracy and reliability of three different analysis methods to identify pharmacologically induced changes in dopamine release and uptake in freely moving C57BL/6J mice. The D1-like receptor antagonist …

The Role Of Tgf-Beta Superfamily Members In Immune Homeostasis And Disease, Natalie Eva Nieuwenhuizen, Ioannis Eleftherianos, Piotr Jan Kraj, Maria Semitekolou

Biological Sciences Faculty Publications

[Introduction] The Transforming Growth Factor beta (TGF-beta) superfamily, encompassing molecules such as TGFs, activins, Bone Morphogenetic Proteins (BMPs), Growth/Differentiation Factor (GDFs) and Nodals, represents the largest family of growth and differentiation factors, playing crucial roles in developmental and physiological processes across animal species (1). These molecules are integral to tissue homeostasis and cell fate determination. Among them, TGF-beta is particularly noted for its regulatory influence on immune responses and tissue fibrosis (2, 3). Recent research has expanded our understanding of the immune functions of other superfamily members, including activin A and BMPs (4). These molecules signal through receptor complexes composed …

Raemap: Real-Time Advanced Eye Movements Analysis Pipeline, Gavindya Jayawardena

Computer Science Theses & Dissertations

Eye-tracking offers insights into human cognition and attention allocation by capturing and interpreting eye movements. Traditionally, eye tracking research has relied on offline analysis methods, requiring post-experiment processing to derive insights from gaze data. This approach limits its applicability in contexts requiring immediate feedback and adaptive responses based on real-time gaze behaviors. Recent advancements in computing power and eye tracking technology have enabled a shift towards real-time analysis, allowing modern systems to interpret gaze data with minimal latency, facilitating integration into interactive applications and experiments. Despite these advancements, existing tools often face challenges with real-time computation of advanced gaze measures …

Use Of Ultrasound For Identification Of Musculoskeletal Injury In Active Populations, Kathleen Karen Hogan

Rehabilitation Sciences Theses & Dissertations

Lower extremity tendinopathies and fasciopathy conditions are prevalent amongst sedentary individuals,^1,2 athletes,^3,4 elite runners,^5,6and military personnel⁷ and can lead to chronic disability and reduction in quality of life. ^8,9 Both tendinopathy and fasciopathy are thought to be mechanical in nature and caused by acute or chronic overloading leading to a disruption in the uniformity of the soft tissue structure. Ultrasound imaging has gained popularity in the last decade among many sports medicine clinicians to gain information regarding tissue structure for musculoskeletal injury (MKSI) management. Ultrasound imaging allows for the evaluation of in-vivo structures and at …

Streaminghub - A Realtime Biosignal Processing Framework For Lab Scale Experimentation, Yasith Jayawardana

Computer Science Theses & Dissertations

In human subjects research, biosignals such as eye movements, heart rate, and brain activity, are often collected and analyzed to find patterns with tangible real-world implications. Modern advancements in technology have sparked interest towards analyzing biosignals in realtime. When developing such algorithms, one may expect to find free, open-source tools that provide easy access to live, recorded, and simulated data streams. Yet, biosignal interfaces are often vendor-specific, making cross-vendor biosignal streaming non-trivial. Likewise, reading biosignal datasets is also non-trivial, as their content may be arranged quite differently.

To combat this divide, we provide the scientific community with a realtime biosignal …

Effects Of Balance Training On Spinal Reflexive Excitability Modulation, Corticospinal Excitability, And Balance Performance In Individuals With Chronic Ankle Instability, Sunghoon Chung

Rehabilitation Sciences Theses & Dissertations

Chronic ankle instability (CAI) is a neurophysiologic deficit resulting in diverse sensorimotor impairments. Following acute ankle sprains, pain, mechanical instability, and joint deafferentation reduce sensory input to the central nervous system (CNS). In response, the CNS sends altered motor signals to lower extremity muscles. These CNS changes contribute to various neuromuscular impairments in CAI patients, the most common of which is reduced balance performance. Specifically, CAI patients struggle to modulate spinal reflex excitability of the soleus muscle when progressing from simpler to more complex balance tasks. This overreliance on spinal reflexes results in inconsistent activation of the ankle stabilizing muscle. …

Gaze Transition Entropy As A Measure Of Attention Allocation In A Dynamic Workspace Involving Automation, Zixin Cui, Tetsuya Sato, Austin Jackson, Sampath Jayarathna, Makoto Itoh, Yusuke Yamani

Psychology Faculty Publications

Real-world work environments require operators to perform multiple tasks with continual support from an automated system. Eye movement is often used as a surrogate measure of operator attention, yet conventional summary measures such as percent dwell time do not capture dynamic transitions of attention in complex visual workspace. This study analyzed eye movement data collected in a controlled a MATB-II task environment using gaze transition entropy analysis. In the study, human subjects performed a compensatory tracking task, a system monitoring task, and a communication task concurrently. The results indicate that both gaze transition entropy and stationary gaze entropy, measures of …

Dental Hygiene Students Reported Physiological Symptoms Associated With Wearing An N95 Respirator Mask, Peyton Shea Butler

Dental Hygiene Theses & Dissertations

Purpose: Physiological symptoms and comfort levels while wearing an N95 respiratory mask has not been examined with dental hygienists. The purpose of this study was to investigate dental hygiene students reported physiological symptoms and comfort perception while wearing an N95 respirator mask during patient care appointments. Methods: After IRB approval (IRB #1987754-2), a 16-item questionnaire was distributed through email to a convenience sample of 65 dental hygiene students. Questions assessed respiratory, dermatologic, cardiac, mask mouth and general physiological symptoms, as well as comfort levels. Additionally, participants were asked to respond to demographic questions and one open ended question inquiring about …

Effect Of Acute Caffeine Ingestion On On-Field Performance In Division 1 Female Field Hockey Players, Nicole Danielle Fredricks

Human Movement Studies & Special Education Theses & Dissertations

This study aimed to determine the effects of acute caffeine ingestion on on-field performance in collegiate female field hockey players. A placebo-controlled, double-blind, randomized, crossover experimental design was utilized. The participants (N=10) were female division 1 field hockey players (age: 20.0 ± 1.6 years). They competed in two 60-minute, off-season scrimmages separated by two weeks. They were randomly assigned to ingest the caffeine, 3 mg/kg of body weight, or placebo treatment 60 minutes before each scrimmage. They wore a PLAYERTEK (Catapult, Australia) global positioning system (GPS) device to track their total distance, sprint distances, power plays, and zone three and …

Effects Of Chewing Time On Gastrointestinal Discomfort, Substrate Use, And Performance During Running, Thomas Geaney

Human Movement Studies & Special Education Theses & Dissertations

Previous research has shown that food particle size affects gastric processing. For example, food particles greater than 3 mm may delay gastric emptying under certain conditions. Delays in gastric emptying can be problematic during aerobic exercise, leading to nausea, bloating, fullness, and other gastrointestinal (GI) symptoms. In some cases, symptoms can be severe enough to negatively affect athletic performance. This study investigated the effects of manipulating chewing duration of carbohydrate sports bars on GI discomfort, physiological responses, and performance during endurance running. This crossover study recruited 12 male runners (age: 36.4 ± 7.2 years, VO_2peak: 57.2 ± 4.7 …

New Frontiers In The Application Of Stable Isotopes To Ecological And Ecophysiological Research, Keith Alan Hobson (Editor), John P. Whiteman (Editor), Seth Newsome (Editor)

Biological Sciences Faculty Books

This Research Topic aims to present cutting-edge applications of stable isotope methods to animal and plant ecology and ecophysiology.

Sound The (Smaller) Alarm: The Triphosphate Magic Spot Nucleotide Pgpp, Areej Malik, Megan A. Hept, Erin B. Purcell

Chemistry & Biochemistry Faculty Publications

It has recently become evident that the bacterial stringent response is regulated by a triphosphate alarmone (pGpp) as well as the canonical tetra- and pentaphosphate alarmones ppGpp and pppGpp [together, (p)ppGpp]. Often dismissed in the past as an artifact or degradation product, pGpp has been confirmed as a deliberate endpoint of multiple synthetic pathways utilizing GMP, (p)ppGpp, or GDP/GTP as precursors. Some early studies concluded that pGpp functionally mimics (p)ppGpp and that its biological role is to make alarmone metabolism less dependent on the guanine energy charge of the cell by allowing GMP-dependent synthesis to continue when GDP/GTP has been …

A Multi-Isotope Approach Reveals Seasonal Variation In The Reliance On Marine Resources, Production Of Metabolic Water, And Ingestion Of Seawater By Two Species Of Coastal Passerine To Maintain Water Balance, Lucas Navarrete, Nico Lübcker, Felipe Alvarez, Roberto Nespolo, Juan Carlos Sanchez-Hernandez, Karin Maldonado, Zachary D. Sharp, John P. Whiteman, Seth D. Newsome, Pablo Sabat

Biological Sciences Faculty Publications

Tracing how free-ranging organisms interact with their environment to maintain water balance is a difficult topic to study for logistical and methodological reasons. We use a novel combination of triple-oxygen stable isotope analyses of water extracted from plasma (δ¹⁶O, δ¹⁷O, δ¹⁸O) and bulk tissue carbon (δ¹³C) and nitrogen (δ¹⁵N) isotopes of feathers and blood to estimate the proportional contribution of marine resources, seawater, and metabolic water used by two species of unique songbirds (genus Cinclodes) to maintain their water balance in a seasonal coastal environment. We …

Integrative Physiology-Coupled Pilot-Centered Flight Simulation, Shawn C. Harrison

Electrical & Computer Engineering Theses & Dissertations

Maintaining the pilot’s physiological performance envelope within the limits of human capabilities may be crucial for avoiding hazardous physiological episodes in fighter aircraft that compromise safety. The main physiological episode of interest is impaired pilot respiration, better known as hypoxia caused by a high fraction of inspired oxygen (FiO₂) at high altitudes and variation in accelerative gravitational forces (g-forces). Integrated into fighter aircraft is an Onboard Oxygen Generating System (OBOGS) developed to mitigate the necessity of gaseous and liquid oxygen cannisters [1]. OBOGS act as a life support in hypoxic environments by providing oxygen-rich air, thereby oxygenating the …

Comparison Of Spine–Pelvis Kinematics Variability During Sit-To-Stand And Stand-To-Sit In People With & Without Chronic Low Back Pain: A Vector Coding And Statistical Parametric Mapping Approach, Narges Jangjoo, Elham Alijanpour, Saeid Khodabakhsh, Seyed Sadredin Shojaedin, Roozbeh Naemi

Rehabilitation Sciences Faculty Publications

There is evidence in the literature to suggest that low back pain may change spine–pelvis coordination during activities of daily living. This study aimed to compare the variability of the spine– pelvis coordination during sit-to-stand in people with and without LBP. Ten healthy individuals with a history of LBP and ten individuals without history of LBP participated in this study. Three-dimensional kinematic data of the upper trunk (UT), lower trunk (LT), lower back (LB), and pelvis segments during sit-to-stand and stand-to-sit were recorded using a multi-segmental spine and pelvis models using a motion capture system. The coordination patterns and the …

Engineering Of Ideal Systems For The Study And Direction Of Stem Cell Asymmetrical Division And Fate Determination, Martina Zamponi

Biomedical Engineering Theses & Dissertations

The cellular microenvironment varies significantly across tissues, and it is constituted by both resident cells and the macromolecules they are exposed to. Cues that the cells receive from the microenvironment, as well as the signaling transmitted to it, affect their physiology and behavior. This notion is valid in the context of stem cells, which are susceptible to biochemical and biomechanical signaling exchanged with the microenvironment, and which plays a fundamental role in establishing fate determination and cell differentiation events. The definition of the molecular mechanisms that drive stem cell asymmetrical division, and how these are modulated by microenvironmental signaling, is …

The Associations Of Cardiovascular Disease, Physical Activity Intensities, And Measures Of Obesity On Static Balance In Middle-Aged And Older Adults, Hannah Martha Twiddy

Human Movement Studies & Special Education Theses & Dissertations

The burden of falls is widely known in older adults, though less research has targeted middle-aged adults (40-64 years of age), particularly at the population level. The purpose of this dissertation was to explore the roles of cardiovascular disease, physical activity (PA) intensity, and body anthropometrics on balance among middle-aged adults. Study 1 sought to determine if balance was impaired in middle-aged adults with poor ankle-brachial pressure index (ABPI), a marker of cardiovascular disease. Study 2 determined the associations between PA intensity with odds of having good static balance. Study 3 explored how strongly a variety of anthropometric measures, including …

Hsp90 Inhibitors Modulate Sars-Cov-2 Spike Protein Subunit 1-Induced Human Pulmonary Microvascular Endothelial Activation And Barrier Dysfunction, Ruben Manuel Luciano Colunga Biancatelli, Pavel Solopov, Betsy W. Gregory, Yara Khodour, John D. Catravas

Bioelectrics Publications

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused more than 5 million deaths worldwide. Multiple reports indicate that the endothelium is involved during SARS-Cov-2-related disease (COVID-19). Indeed, COVID-19 patients display increased thrombophilia with arterial and venous embolism and lung microcapillary thrombotic disease as major determinants of deaths. The pathophysiology of endothelial dysfunction in COVID-19 is not completely understood. We have investigated the role of subunit 1 of the SARS-CoV-2 spike protein (S1SP) in eliciting endothelial barrier dysfunction, characterized dose and time relationships, and tested the hypothesis that heat shock protein 90 (HSP90) inhibitors would prevent and repair such injury. S1SP …

Pulmonary Capillary Recruitment And Distention In Mammalian Lungs: Species Similarities, David Langleben, Benjamin D. Fox, Stylianos E. Orfanos, Michele Giovinazzo, John D. Catravas

Bioelectrics Publications

Pulmonary arterial pressure rises minimally during exercise. The pulmonary microcirculation accommodates increasing blood flow via recruitment of pulmonary capillaries and, at higher flows, by distention of already perfused capillaries. The flow transition range between recruitment and distention has not been studied or compared across mammalian species, including humans. We hypothesised that the range would be similar. Functional pulmonary capillary surface area (FCSA) can be estimated using validated metabolic techniques. We reviewed data from previous studies in three mammalian species (perfused rabbit lungs and dog lung lobes, and exercising humans) and generated blood flow-FCSA curves over a range of flows. We …

Toxic Effects Of Silver Ions On Early Developing Zebrafish Embryos Distinguished From Silver Nanoparticles, Martha S. Johnson, Preeyaporn Songkiatisak, Pavan Kumar Cherukuri, Xiao-Hong Nancy Xu

Chemistry & Biochemistry Faculty Publications

Currently, effects of nanomaterials and their ions, such as silver nanoparticles (Ag NPs) and silver ions (Ag⁺), on living organisms are not yet fully understood. One of the vital questions is whether nanomaterials have distinctive effects on living organisms from any other conventional chemicals (e.g., their ions), owing to their unique physicochemical properties. Due to various experimental protocols, studies of this crucial question have been inconclusive, which hinders rational design of effective regulatory guidelines for safely handling NPs. In this study, we chronically exposed early developing zebrafish embryos (cleavage-stage, 2 hours post-fertilization, hpf) to a dilution series of …

The Impact Of Muscular Strength On Cardiovascular Disease Risk Factors, Joel Ernest Harden

Human Movement Studies & Special Education Theses & Dissertations

The purpose of this study was to determine the associations between isokinetic leg muscular strength and cardiovascular disease (CVD) risk factor characterizations in Americans aged 50 and older. Using a publicly available dataset from the National Health and Nutrition Examination Survey (NHANES), a secondary analysis was conducted on participants (males ≥50 yrs; females ≥55 yrs; N=10,858) pooled from 1999 to 2002. CVD risk factors were determined using the American College of Sports Medicine (ACSM) cutoff values, with all nine ACSM risk factors analyzed. CVD risk factor characterization was determined by creating CVD risk factor profiles (i.e., the total number of …

Effect Of A 2-Week Relaxing Music Intervention On Anxiety, Stress, And Gut Symptoms In Aerobic Exercisers, Halie Marisa Maass

Human Movement Studies & Special Education Theses & Dissertations

The purpose of this study was to determine the impact of a two-week relaxing music intervention on stress, anxiety, and gastrointestinal (GI) symptoms in exercisers with at least mild anxiety and exercise-related GI symptoms. Block randomization was used to allocate 15 women and two men into control (n = 8) or intervention (n = 9) groups following a one-week baseline. During the baseline period, participants recorded details of their aerobic exercise sessions and discomfort with GI symptoms (nausea, regurgitation/reflux, stomach fullness, bloating, abdominal cramps, gas, the urge to defecate). Following randomization, both groups tracked these same details for two additional …

Computational Analysis Of Type 3 Iodothyronine Deiodinase: Potential Inhibitors, Substrate Binding, And Dimer Structure, Eric Scott Marsan

Chemistry & Biochemistry Theses & Dissertations

Thyroid hormones (THs) in mammalian tissues are crucial for development and maintaining metabolic homeostasis. Iodothyronine deiodinases (Dios) remove iodines from THs by a selenocysteine (Sec) residue, which either activates or inactivates them. Halogen bonding (XB) has been proposed to describe the interaction between the Se and I atoms of the T4-Dio complex. Disruption of TH homeostasis by xenobiotics, such as polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) can cause deleterious effects on the endocrine system. Experimental studies have indicated that PBDEs and PCBs could disrupt TH homeostasis by inhibiting Dio through XB formation. However, no current quantitative study exists …

Evidence For The Use Of Dynamic Maximum Normalization Method Of Muscle Activation During Weight Back Squats, Eva Maddox, Hunter J. Bennett

College of Education & Professional Studies (Darden) Posters

The purpose of this study was to evaluate intra and inter-participant variability and reliability of muscle activations when analyzed using maximum voluntary isometric contractions (MVIC) and dynamic maximum (DMVC) normalization methods. Muscle activations were collected on twenty-seven participants (13 females, 14 males) performing one-repetition maximum (1RM) and submaximum (80%) back squats. Data from submaximum squats were normalized to MVICs and DMVCs. Data were compared using intra-class correlations over two testing days, variance ratio, and coefficients of variation. Mixed-model ANOVAs were used to elucidate the influence on intra- (method) and inter- (sex) subject variability. Reliability levels were good for rectus femoris …