Life Sciences Commons^™

Changes In Human Walking Dynamics Induced By Uneven Terrain Are Reduced With Ongoing Exposure, But A Higher Variability Persists, Jenny A. Kent, Joel H. Sommerfeld, Nicholas Stergiou

Journal Articles

During walking, uneven terrain alters the action of the ground reaction force from stride to stride. The extent to which such environmental inconsistencies are withstood may be revealed by the regulation of whole-body angular momentum (L) during walking. L quantifies the balance of momenta of the body segments (thigh, trunk, etc.) about their combined center of mass, and remains close to zero during level walking. A failure to constrain L has been linked to falls. The aim of this study was to explore the ability of young adults to orchestrate their movement on uneven terrain, illustrated by the …

Salt Restriction Lowers Blood Pressure At Rest And During Exercise Without Altering Peripheral Hemodynamics In Hypertensive Individuals, Stephen M. Ratchford, Ryan M. Broxterman, Taylor La Salle, Oh-Sung Kwon, Song-Young Park, Paul N. Hopkins, Russell S. Richardson, Joel D. Trinity

Health and Kinesiology Faculty Publications

Dietary salt restriction is a well-established approach to lower blood pressure and reduce cardiovascular disease risk in hypertensive individuals. However, little is currently known regarding the effects of salt restriction on central and peripheral hemodynamic responses to exercise in those with hypertension. Therefore, this study sought to determine the impact of salt restriction on the central and peripheral hemodynamic responses to static-intermittent handgrip (HG) and dynamic single-leg knee extension (KE) exercise in individuals with hypertension. Twenty-two subjects (14 men and 8 women, 51 ± 10 yr, 173 ± 11 cm, 99 ± 23 kg) forewent their antihypertensive medication use for …

Structure Of The 5′ Untranslated Region Of Enteroviral Genomic Rna, Bejan Mahmud, Christopher M. Horn, William E. Tapprich

Biology Faculty Publications

Enteroviral RNA genomes share a long, highly structured 5= untranslated region (5= UTR) containing a type I internal ribosome entry site (IRES). The 5= UTR is composed of stably folded RNA domains connected by unstructured RNA regions. Proper folding and functioning of the 5= UTR underlies the efficiency of viral replication and also determines viral virulence. We have characterized the structure of 5= UTR genomic RNA from coxsackievirus B3 using selective 2=-hydroxyl acylation analyzed by primer extension (SHAPE) and base-specific chemical probes in solution. Our results revealed novel structural features, including realignment of major domains, newly identified long-range interactions, and …

Abstract 482: Differences In Ground Reaction Forces And Chest Compression Release Velocity In Professional And Lay Rescuers With And Without The Use Of Real-Time Cpr Feedback, Lyra Clark, Ben Senderling, Jeff R. Gould, Chris Kaufman, Nicholas Stergiou

Journal Articles

Purpose: Chest compression release velocity (CCRV) has been associated with survival and favorable neurological outcome after cardiac resuscitation. Both complete chest release and high CCRV contribute to improved venous return during CPR. Differences in compression forces delivered by professional and lay rescuers are reported, which may contribute to differences in CCRV. The aim of this pilot study was to investigate differences in ground reaction force (GRF) and CCRV between professional and lay rescuers during CPR performed on a manikin with and without real-time feedback.

Methods: Professional (n = 5) and lay rescuers (n = 11) performed two minutes of continuous …

Effect Of Sampling Frequency On Fractal Fluctuations During Treadmill Walking, Vivien Marmelat, Austin Duncan, Shane Meltz

Journal Articles

The temporal dynamics of stride-to-stride fluctuations in steady-state walking reveal important information about locomotor control and can be quantified using so-called fractal analyses, notably the detrended fluctuation analysis (DFA). Gait dynamics are often collected during treadmill walking using 3-D motion capture to identify gait events from kinematic data. The sampling frequency of motion capture systems may impact the precision of event detection and consequently impact the quantification of stride-to-stride variability. This study aimed i) to determine if collecting multiple walking trials with different sampling frequency affects DFA values of spatiotemporal parameters during treadmill walking, and ii) to determine the reliability …

Running Economy - A Comprehensive Review For Passive Force Generation, Christos Ziliaskoudis, Song-Young Park, Sang-Ho Lee

Health and Kinesiology Faculty Publications

Running economy is considered a major determinant of distance running performance. Enhancing the body’s ability for passive force generation could have a positive effect on running economy by minimizing the energy cost required for the propulsion of the body. Thus, the purpose of this comprehensive review was to provide a list of modifiable factors that promote this ability. The interest was focused on lower-limb stiffness, as it is a factor of great influence and at the same time can be modified with training and specific biomechanical adjustments. Although it appears that no clear instructions can be provided to athletes and …

Impacts Of Aquatic Walking On Arterial Stiffness, Exercise Tolerance, And Physical Function In Patients With Peripheral Artery Disease: A Randomized Clinical Trial, Song-Young Park, Elizabeth J. Pekas, Yi-Sub Kwak

Health and Kinesiology Faculty Publications

Peripheral artery disease (PAD) is an atherosclerotic disease that is associated with attenuated vascular function, cardiorespiratory capacity, physical function, and muscular strength. It is essential to combat these negative effects on health by incorporating lifestyle interventions to slow disease progression, such as exercise. We sought to examine the effects of aquatic walking exercise on cardiovascular function, cardiorespiratory capacity [maximal volume of oxygen consumption (V̇o2max)], exercise tolerance [6-min walking distance (6MWD)], physical function, muscular strength, and body composition in patients with PAD. Patients with PAD (n = 72) were recruited and randomly assigned to a 12-wk aquatic walking training group …

Ankle And Midtarsal Joint Quasi-Stiffness During Walking With Added Mass, Andrew M. Kern, Nikolaos Papachatzis, Jeffrey M. Patterson, Dustin A. Bruening, Kota Z. Takahashi

Journal Articles

Examination of how the ankle and midtarsal joints modulate stiffness in response to increased force demand will aid understanding of overall limb function and inform the development of bio-inspired assistive and robotic devices. The purpose of this study is to identify how ankle and midtarsal joint quasi-stiffness are affected by added body mass during over-ground walking. Healthy participants walked barefoot over-ground at 1.25 m/s wearing a weighted vest with 0%, 15% and 30% additional body mass. The effect of added mass was investigated on ankle and midtarsal joint range of motion (ROM), peak moment and quasi-stiffness. Joint quasi-stiffness was broken …

Digital Divide Among Caregivers Of Chronic Disease Patients, Ayokunle Olagoke, Harveen Kaur, Ashley M. Hughes

Health and Kinesiology Faculty Publications

Expansive and rapid growth of technology creates unprecedented patient access to health information, including timely communication with care providers via patient portals and the ability to access information regarding specific disease(s) (e.g., cancer). However, several forms of digital engagement with health providers require access and use of reliable internet access. A “digital divide” is used to describe demographic differences which contribute to a patient’s use or disuse of patient portals; prior research have noted disparities in lack of reliable internet access. Despite the prevalence of informal caregivers in patient care, little is known about internet access and use among informal …

Kinematic Differences Between Professional And Lay Rescuers With And Without The Use Of Real-Time Cpr Feedback, Lyra Clark, Ben Senderling, Jeff R. Gould, Chris Kaufman, Nicholas Stergiou

Journal Articles

Purpose: Guideline-compliant cardiopulmonary resuscitation (CPR) performance can be achieved with training and use of real-time feedback. Kinematic differences are reported between experts and novices in various motor tasks. The aim of this pilot study was to investigate differences in kinematics between professional and lay rescuers during CPR performed on a manikin with and without feedback.

Methods: Professional (n = 5) and lay rescuers (n = 11) performed two minutes of continuous chest compressions on a manikin for two trials. Real-time CPR feedback provided by a defibrillator was disabled in the first trial and enabled in the second. CPR …

Resolving The Genetic Paradox Of Invasions: Preadapted Genomes And Postintroduction Hybridization Of Bigheaded Carps In The Mississippi River Basin, Jun Wang, Sarah Gaughan, James T. Lamer, Cao Deng, Wanting Hu, Michael Wachholtz, Shishang Qin, Hu Nie, Xiaolin Liao, Qufei Ling, Weitao Li, Lifeng Zhu, Louis Bernatchez, Chenghui Wang, Guoqing Lu

Biology Faculty Publications

The genetic paradox of biological invasions is complex and multifaceted. In particular, the relative role of disparate propagule sources and genetic adaptation through postintroduction hybridization has remained largely unexplored. To add resolution to this paradox, we investigate the genetic architecture responsible for the invasion of two invasive Asian carp species, bighead carp (Hypophthalmichthys nobilis) and silver carp (H. molitrix) (bigheaded carps) that experience extensive hybridization in the Mississippi River Basin (MRB). We sequenced the genomes of bighead and silver carps (~1.08G bp and ~1.15G bp, respectively) and their hybrids collected from the MRB. We found moderate‐to‐high …

A Low-Cost, Wireless Near-Infrared Spectroscopy Device Detects The Presence Of Lower Extremity Atherosclerosis As Measured By Computed Tomographic Angiography And Characterizes Walking Impairment In Peripheral Artery Disease, Matthew A. Fuglestad, Hernan Hernandez, Yue Gao, Henamari Ybay, Molly Schieber, Katyarina E. Brunette, Sara A. Myers, George P. Casale, Iraklis Pipinos

Journal Articles

Background

Methods

Impacts Of Hiv Cure Interventions On Viral Reservoirs In Tissues, Paul W. Denton, Ole S. Søgaard, Martin Tolstrup

Biology Faculty Publications

HIV reservoirs persist in infected individuals despite combination antiretroviral therapy and can be identified in secondary lymphoid tissues, in intestinal tissues, in the central nervous system as well as in blood. Clinical trials have begun to explore effects of small molecule interventions to perturb the latent viral infection, but only limited information is available regarding the impacts of HIV cure-related clinical interventions on viral reservoirs found in tissues. Of the 14 HIV cure-related clinical trials since 2012 that have evaluated the effects of small molecule interventions in vivo, four trials have examined the impacts of the interventions in peripheral …

Supervised Walking Exercise Therapy Improves Gait Biomechanics In Patients With Peripheral Artery Diseas, Molly Schieber, Iraklis Pipinos, Jason M. Johanning, George P. Casale, Mark A. Williams, Holly Despiegelaere, Ben Senderling, Sara A. Myers

Journal Articles

Objective

Methods

Incidence, Trends And Predictors Of Palliative Care Consultation Among Patients Admitted For Lvad Implantation In The United States, Olakanmi Olagoke, Olisa Ezegwu, Ayokunle Olagoke, Yasmeen Golzar

Health and Kinesiology Faculty Publications

Aim

Left ventricular assist devices (LVAD) have become an important part of advanced heart failure management either as a bridge to transplantation or destination therapy. Patients with advanced heart failure have a poor prognosis and may benefit from palliative care (PC) services. However, there is scarce data regarding the incidence, trends, and predictors of palliative care consultation among patients undergoing LVAD implantation. The main objective of this study is to assess the incidence, trends, and predictors of PC referral in LVAD recipients using the Nationwide Inpatient Sample (NIS) database from 2010 till 2014.

Methods

We conducted a weighted analysis on …

Exploring Rural And Urban Go Nap Sacc Trained Child Care Providers Perceptions And Needs Regarding The Promotion Of Physical Activity And Healthy Eating, Kailey Snyder, Zainab Rida, Emily Hulse, Dipti Dev, Danae Dinkel

Health and Kinesiology Faculty Publications

Introduction: Early childhood is an optimal time to support the development of physical activity and healthy eating behaviors. As over half of children are cared for in family child care homes and child care centers it is crucial to ensure these behaviors are being supported in the childcare setting. One such process that supports provider’s education and implementation of healthy behaviors in the childcare setting is the Nutrition and Physical Activity Assessment in Child Care (Go NAP SACC). However, after participation in Go NAP SACC, little is known regarding how to further support providers in their promotion of healthy behaviors. …

Locomotor Patterns Change Over Time During Walking On An Uneven Surface, Jenny A. Kent, Joel H. Sommerfeld, Mukul Mukherjee, Kota Z. Takahashi, Nicholas Stergiou

Journal Articles

During walking, uneven surfaces impose new demands for controlling balance and forward progression at each step. It is unknown to what extent walking may be refined given an amount of stride-to-stride unpredictability at the distal level. Here, we explored the effects of an uneven terrain surface on whole-body locomotor dynamics immediately following exposure and after a familiarization period. Eleven young, unimpaired adults walked for 12 min on flat and uneven terrain treadmills. The whole-body center of mass excursion range (COM_exc) and peak velocity (COM_vel), step length and width were estimated. On first exposure to uneven terrain, …

Contextual Fear Learning And Memory Differ Between Stress Coping Styles In Zebrafish, Matthew R. Baker, Ryan Y. Wong

Biology Faculty Publications

Animals frequently overcome stressors and the ability to learn and recall these salient experiences is essential to an individual’s survival. As part of an animal’s stress coping style, behavioral and physiological responses to stressors are often consistent across contexts and time. However, we are only beginning to understand how cognitive traits can be biased by different coping styles. Here we investigate learning and memory differences in zebrafish (Danio rerio) displaying proactive and reactive stress coping styles. We assessed learning rate and memory duration using an associative fear conditioning paradigm that trained zebrafish to associate a context with exposure to a …

Tlr9 Agonist Mgn1703 Enhances B Cell Differentiation And Function In Lymph Nodes, Mariane H. Schleimann, Maria-Louise Kobberø, Line K. Vibholm, Katherine Kjær, Leila B. Giron, Kathleen Busman-Sahay, Chi Ngai Chan, Michael Nekorchuk, Manuel Schmidt, Burghardt Wittig, Tine E. Damsgaard, Peter Ahlburg, Michel B. Hellfritzsch, Kaja Zuwala, Frederik H. Rothemejer, Rikke Olesen, Phillipp Schommers, Florian Klein, Harsh Dweep, Andrew Kossenkov, Jens R. Nyengaard, Jacob D. Estes, Mohamed Abdel-Mohsen, Lars Østergaard, Ole S. Søgaard, Paul W. Denton

Biology Faculty Publications

Background

TLR9 agonists are being developed as immunotherapy against malignancies and infections. TLR9 is primarily expressed in B cells and plasmacytoid dendritic cells (pDCs). TLR9 signalling may be critically important for B cell activity in lymph nodes but little is known about the in vivo impact of TLR9 agonism on human lymph node B cells. As a pre-defined sub-study within our clinical trial investigating TLR9 agonist MGN1703 (lefitolimod) treatment in the context of developing HIV cure strategies (NCT02443935), we assessed TLR9 agonist-mediated effects in lymph nodes.

Methods

Participants received MGN1703 for 24 weeks concurrent with antiretroviral therapy. Seven …

The Foot And Ankle Structures Reveal Emergent Properties Analogous To Passive Springs During Human Walking, Erica Hedrick, Steven J. Stanhope, Kota Z. Takahashi

Journal Articles

An objective understanding of human foot and ankle function can drive innovations of bio-inspired wearable devices. Specifically, knowledge regarding how mechanical force and work are produced within the human foot-ankle structures can help determine what type of materials or components are required to engineer devices. In this study, we characterized the combined functions of the foot and ankle structures during walking by synthesizing the total force, displacement, and work profiles from structures distal to the shank. Eleven healthy adults walked at four scaled speeds. We quantified the ground reaction force and center-of-pressure displacement in the shank’s coordinate system during stance …

Alterations In Cortical Activation Among Individuals With Chronic Ankle Instability During Single-Limb Postural Control, Adam Rosen, Jennifer M. Yentes, Melanie L. Mcgrath, Arthur C. Maerlender, Sara A. Myers, Mukul Mukherjee

Journal Articles

Context

Chronic ankle instability (CAI) is characterized by repetitive ankle sprains and perceived instability. Whereas the underlying cause of CAI is disputed, alterations in cortical motor functioning may contribute to the perceived dysfunction. Objective

To assess differences in cortical activity during single-limb stance among control, coper, and CAI groups. Design

Cross-sectional study. Setting

Biomechanics laboratory. Patients or Other Participants

A total of 31 individuals (10 men, 21 women; age = 22.3 ± 2.4 years, height = 169.6 ± 9.7 cm, mass = 70.6 ± 11.6 kg), who were classified into control (n = 13), coper (n = 7), and CAI …

Differences In Stress Reactivity Between Zebrafish With Alternative Stress Coping Styles, Ryan Y. Wong, Jeffrey French, Jacalyn B. Russ

Biology Faculty Publications

Animals experience stress in a variety of contexts and the behavioural and neuroendocrine responses to stress can vary among conspecifics. The responses across stressors often covary within an individual and are consistently different between individuals, which represent distinct stress coping styles (e.g. proactive and reactive). While studies have identified differences in peak glucocorticoid levels, less is known about how cortisol levels differ between stress coping styles at other time points of the glucocorticoid stress response. Here we quantified whole-body cortisol levels and stress-related behaviours (e.g. depth preference, movement) at time points representing the rise and recovery periods of the stress …

Strong Relationship Between Vascular Function In The Coronary And Brachial Arteries: A Clinical Coming Of Age For The Updated Flow-Mediated Dilation Test?, Ryan M. Broxterman, Melissa A. Witman, Joel D. Trinity, H. Jonathan Groot, Matthew J. Rossman, Song-Young Park, Simon Malenfant, Jayson R. Gifford, Oh-Sung Kwon, Soung Hun Park, Catherine L. Jarrett, Katherine L. Shields, Jay R. Hydren, Angela V. Bisconti, Theophilus Owan, Anu Abraham, Anwar Tandar, Charles Y. Lui, Brigham R. Smith, Russell S. Richardson

Health and Kinesiology Faculty Publications

Early detection of coronary artery dysfunction is of paramount cardiovascular clinical importance, but a noninvasive assessment is lacking. Indeed, the brachial artery flow-mediated dilation test only weakly correlated with acetylcholine-induced coronary artery function (r=0.36). However, brachial artery flow-mediated dilation methodologies have, over time, substantially improved. This study sought to determine if updates to this technique have improved the relationship with coronary artery function and the noninvasive indication of coronary artery dysfunction. Coronary artery and brachial artery function were assessed in 28 patients referred for cardiac catheterization (61±11 years). Coronary artery function was determined by the change in artery diameter with …

Synchronization Dynamics Modulates Stride-To-Stride Fluctuations When Walking To An Invariant But Not To A Fractal-Like Stimulus, Joao R. Vaz, Boman Groff, Douglas Rowen, Brian Knarr, Nicholas Stergiou

Journal Articles

Walking with different types of cueing/stimulus (i.e. auditory, visual) has been shown to alter gait variability, thus emerging as an innovative therapeutical tool to restore abnormal gait variability in clinical populations. However, the majority of the research in this area has focused on auditory stimuli while visual stimuli are an understudied alternative that needs more attention, particularly due to the natural dependence on vision during walking. Furthermore, the time differences between the occurrences of the walking steps and the sensory cues, also known as asynchronies, have also received minimal attention, even though the ability to synchronize with different stimuli is …

An Altered Spatiotemporal Gait Adjustment During A Virtual Obstacle Crossing Task In Patients With Diabetic Peripheral Neuropathy, Chun-Kai Huang, Vijay Shivaswamy, Pariwat Thaisetthawatkul, Lynn Mack, Nicholas Stergiou, Ka-Chun Siu

Journal Articles

This study investigates spatiotemporal gait adjustments that occur while stepping over virtual obstacles during treadmill walking in people with/without diabetic peripheral neuropathy (DPN). Eleven adults with Type 2 diabetes mellitus, ten DPN, and 11 age-matched healthy adults (HTY) participated in this study. They stepped over forthcoming virtual obstacles during treadmill walking. Outcomes such as success rate, spatiotemporal gait characteristics during obstacle crossing, and correlations between these variables were evaluated. The results partially supported our hypotheses that when comparing with HTY and DM, people with DPN adopted a crossing strategy which decreased obstacle crossing success rate and maximal toe elevation, …

An Exploration Of Infant And Toddler Unstructured Outdoor Play, Danae Dinkel, Kailey Snyder, Tyler Patterson, Shane Warehime, Miriam E. Kuhn, Deborah Basler Wisneski

Health and Kinesiology Faculty Publications

Unstructured outdoor play is important for children's development. The present study examined infants’ and toddlers’ physical and social unstructured outdoor play behaviors within childcare centers. Children's outdoor play behaviors were video recorded at two centers (A&B) and assessed using a modified version of the Observational System for Recording Physical Activity in Children in Preschool (OSRAC-P). Children in this study primarily took part in active play (56.7%) and engaged in play without any type of prompting from a teacher (91.2%). There was a significant interaction between the effect of center and location on physically active play (p < 0.001). Children at Center B were most active in open play areas (77.6%), while children at Center A were most active in gross motor play areas (72.2%). In sum, the outdoor play environment influences infants’ and toddlers’ physical and social play behaviors; however, more research is needed to determine the optimal environment for development.

Uneven Terrain Exacerbates The Deficits Of A Passive Prosthesis In The Regulation Of Whole Body Angular Momentum In Individuals With A Unilateral Transtibial Amputation, Jenny A. Kent, Kota Z. Takahashi, Nicholas Stergiou

Journal Articles

Background

Uneven ground is a frequently encountered, yet little-studied challenge for individuals with amputation. The absence of control at the prosthetic ankle to facilitate correction for surface inconsistencies, and diminished sensory input from the extremity, add unpredictability to an already complex control problem, and leave limited means to produce appropriate corrective responses in a timely manner. Whole body angular momentum, L, and its variability across several strides may provide insight into the extent to which an individual can regulate their movement in such a context. The aim of this study was to explore L in individuals with a transtibial amputation, …

Gait Mechanics Differences Between Healthy Controls And Patients With Peripheral Artery Disease After Adjusting For Gait Velocity, Stride Length, And Step Width, John D. Mccamley, Eric Cutler, Kendra K. Schmid, Shane R. Wurdeman, Jason Johanning, Iraklis Pipinos, Sara A. Myers

Journal Articles

Patients with peripheral artery disease (PAD) experience significant leg dysfunction. The effects of PAD on gait include shortened steps, slower walking velocity, and altered gait kinematics and kinetics, which may confound joint torques and power measurements. Spatiotemporal parameters and joint torques and powers were calculated and compared between 20 patients with PAD and 20 healthy controls using independent t tests. Separate analysis of covariance models were used to evaluate group differences after independently adjusting for gait velocity, stride length, and step width. Compared with healthy controls, patients with PAD exhibited reduced peak extensor and flexor torques at the knee and …

Burning And Mowing Similarly Increase Prairie Plant Production In The Spring, But Not Due To Increased Soil Temperatures, Timothy L. Dickson

Biology Faculty Publications

Burning and mowing are two of the most common grassland disturbances across millions of hectares worldwide, but uncertainty remains about when and why these disturbances increase plant production. One of the main hypotheses for increased plant production is that disturbances increase soil temperature in the early growing season and thereby increase plant growth. I tested this hypothesis using a multi‐decade study of the frequency (annual or quadrennial) and season (spring, summer, or autumn) of reconstructed tallgrass prairie burning and mowing. To determine plant production, I measured aboveground biomass during three periods of the 2015 growing season: (1) prior to mid‐May; …

Selection Procedures For The Largest Lyapunov Exponent In Gait Biomechanics, Peter C. Raffalt, Jenny A. Kent, Shane R. Wurdeman, Nicholas Stergiou

Journal Articles

The present study was aimed at investigating the effectiveness of the Wolf et al. (LyE_W) and Rosenstein et al. largest Lyapunov Exponent (LyE_R) algorithms to differentiate data sets with distinctly different temporal structures. The three-dimensional displacement of the sacrum was recorded from healthy subjects during walking and running at two speeds; one low speed close to the preferred walking speed and one high speed close to the preferred running speed. LyE_R and LyE_W were calculated using four different time series normalization procedures. The performance of the algorithms were evaluated based on their ability to return relative low values for slow …