Flow Through The Nasal Cavity Of The Spiny Dogfish, Squalus Acanthias, L. L. Timm-Davis, Frank E. Fish

Biology Faculty Publications

The nasal cavity of spiny dogfish is a blind capsule with no internal connection to the oral cavity. Water is envisioned to flow through the cavity in a smooth, continuous flow pattern; however, this assumption is based on previous descriptions of the morphology of the olfactory cavity. No experimentation on the flow through the internal nasal cavity has been reported. Morphology of the head of the spiny dogfish (Squalus acanthias) does not suggest a close external connection between the oral and nasal systems. However, dye visualization showed that there was flow through the nasal apparatus and from the excurrent nostril …

Six Degree-Of-Freedom Analysis Of Hip, Knee, Ankle And Foot Provides Updated Understanding Of Biomechanical Work During Human Walking, Karl E. Zelik, Kota Z. Takahashi, Gregory S. Sawicki

Journal Articles

Measuring biomechanical work performed by humans and other animals is critical for understanding muscle–tendon function, jointspecific contributions and energy-saving mechanisms during locomotion. Inverse dynamics is often employed to estimate jointlevel contributions, and deformable body estimates can be used to study work performed by the foot. We recently discovered that these commonly used experimental estimates fail to explain whole-body energy changes observed during human walking. By re-analyzing previously published data, we found that about 25% (8 J) of total positive energy changes of/about the body’s center-of-mass and >30% of the energy changes during the Push-off phase of walking were not explained …

A Neuromechanics-Based Powered Ankle Exoskeleton To Assist Walking Post-Stroke: A Feasibility Study, Kota Z. Takahashi, Michael D. Lewek, Gregory S. Sawicki

Journal Articles

Background: In persons post-stroke, diminished ankle joint function can contribute to inadequate gait propulsion. To target paretic ankle impairments, we developed a neuromechanics-based powered ankle exoskeleton. Specifically, this exoskeleton supplies plantarflexion assistance that is proportional to the user’s paretic soleus electromyography (EMG) amplitude only during a phase of gait when the stance limb is subjected to an anteriorly directed ground reaction force (GRF). The purpose of this feasibility study was to examine the short-term effects of the powered ankle exoskeleton on the mechanics and energetics of gait.

Methods: Five subjects with stroke walked with a powered ankle exoskeleton …

A Pilot Study Investigating The Reasons For Playing Through Pain And Injury: Emerging Themes In Men’S And Women’S Collegiate Rugby, Leilani Madrigal, Jamie Robbins, Diane L. Gill, Katherine Wurst

Athletic Performance Research

Collegiate rugby is a competitive, collision sport, yet insufficient empirical evidence exists regarding participants’ perspectives on pain and injury. This study addressed male and female rugby players’ experiences with injury, and their views about playing through pain and injury. Eleven rugby players (five male; six female) competing in USA Rugby’s National College 7’s tournament participated in semi structured interviews, which were recorded, transcribed, and content-analyzed. Two major themes emerged: passion for sport and sport ethic. Passion for sport was composed of (a) love of the sport, (b) meaning of the sport, and (c) desire to be on the field. Sport …

A Methodology For Physically-Based Contact And Meniscus Properties In Rigid-Body Computational Knee Modeling, Stephen Wilson

Open Access Theses & Dissertations

Determining natural inner knee mechanics is a longstanding goal for researchers with applications to prevention and treatment of knee trauma and osteoarthritis. Physical testing has only provided limited information of knee mechanics due to technical challenges and cost. Modeling has been used for decades to obtain some of this otherwise inaccessible information, and recently finite element analysis (FEA) has become a popular means to this end. However, FEA requires time intensive mesh-creation and has large computational requirements. Ideally, model creation should be easy and simulations should be fast to allow for sensitivity analysis. Although allowing easier model creation and offering …

Effects Of Controlled Whole-Body Vibration Training On Reducing Risk Of Falls Among Young Adults With Obesity, Jose Jesus Munoz

Open Access Theses & Dissertations

Introduction: Among people with obesity, several factors increase the risk of falls: an abnormal body mass distribution, muscle weakness, and postural instability. Although standard exercise-based training could change these factors, a significant portion of people with obesity may be unable or unwilling to comply with long duration and high intensity training programs. Therefore, alternative training methods are highly demanded. Growing evidence supports that controlled whole-body vibration (CWBV) training can reduce risk of falls among older adults. No study has yet investigated the potential effect of CWBV training on reducing risk of falls among obese populations. The purpose of this study …

Trunk Postural Control In Unstable Sitting: Effect Of Sex And Low Back Pain Status, Christian Larivière, Dany H. Gagnon, Hakim Mecheri

Études primaires

Background

Adequate neuromuscular control of the lumbar spine is required to prevent lumbar injuries. A trunk postural control test protocol, controlling for the influence of body size on performance, was implemented to carry out between-subject comparisons. The aim of this study was to assess the effect of sex and low back pain status with the use of two measures of trunk postural control, the first based on chair motion, and the second based on trunk motion.

Methods

Thirty-six subjects (with and without low back pain) performed three 60-s trunk postural control trials with their eyes closed while seated on an …

Spatiotemporal Changes Posttreatment In Peripheral Arterial Disease, Sara A. Myers, Neil B. Huben, Jennifer M. Yentes, John D. Mccamley, Elizabeth E. Lyden, Iraklis I. Pipinos, Jason M. Johanning

Journal Articles

Accumulating evidence suggests revascularization of peripheral arterial disease (PAD) limbs results in limited improvement in functional gait parameters, suggesting underlying locomotor system pathology. Spatial and temporal (ST) gait parameters are well studied in patients with PAD at baseline and are abnormal when compared to controls. The purpose of this study was to systematically review and critically analyze the available data on ST gait parameters before and after interventions. A full review of literature was conducted and articles were included which examined ST gait parameters before and after intervention (revascularization and exercise). Thirty-three intervention articles were identified based on 154 articles …

The Effects Of Muscle Cross-Sectional Area On The Physical Working Capacity At The Fatigue Threshold, Meghan B. Barry, Jorge M. Zuniga, Makenna M. Brown, William M. Garnett, Zachary V. Hadden, Paul K. Nguyen, Geoffrey A. Supplee, Claire J. Svobada

Journal Articles

Purpose: The purpose of this study was to examine the effects of quadriceps cross-sectional area (CSA) of the dominant quadriceps muscle in the assessment of the physical working capacity at the fatigue threshold (PWCFT) during incremental cycle ergometry. Methods: Eighteen adults (9 men and 9 women; mean age ± SD = 20.5 ± 1.04 yr; mean body weight ± SD = 73.9 ± 18.2 kg; mean height ± SD = 172.3 ± 11.5 cm; mean dominant quadriceps CSA ± SD = 68.7 ± 14.5 cm2) performed an incremental cycle ergometry test to exhaustion while the electromyographic (EMG) signals …

Identification Of Intrinsic And Reflexive Contributions To Low-Back Stiffness: Medium-Term Reliability And Construct Validity, Christian Lariviere, Daniel Ludvig, Robert Kearney, Hakim Mecheri, Jean-Maxime Caron, Richard Preuss

Études primaires

This study aimed at testing the reliability and construct validity of a trunk perturbation protocol (TPP) that estimates the intrinsic and reflexive contributions to low-back stiffness. The TPP consists of a series of pseudorandom position-controlled trunk perturbations in an apparatus measuring forces and displacements at the harness surrounding the thorax. Intrinsic and reflexive contributions to low-back stiffness were estimated using a system identification procedure, leading to 12 parameters. Study 1 methods (reliability): 30 subjects performed five 75- s trials, on each of two separate days (eight weeks apart). Reliability was assessed using the generalizability theory, which allowed computing indexes of …

Influence Of Planning Resources On Gait Control In Parkinson’S Disease, Frederico P. Faria

Theses and Dissertations (Comprehensive)

Movement disturbances in individuals with Parkinson’s disease (PD) have been associated with difficulties to plan complex actions. Performance of simple and complex actions overloads resources for individuals with Parkinson’s disease (PD). However, it is unclear if central resources required to plan gait adjustments while walking exacerbate gait disturbances of patients with PD. More specifically, it is unclear how gait impairments, sensory processing, and the dopaminergic system influence the load on processing resources (e.g. cognitive load) during the planning of step modifications. In order to investigate the relative influence of these factors on cognitive load and its impact on gait control, …

The Effect Of Training Older Adults In Tai Chi And Compensatory Stepping On Balance Control, Hannah L. Moore Miss

Theses and Dissertations (Comprehensive)

Abstract

Introduction: In Canadian society, there is a growing prevalence of older adults and one of the main problems facing this generation today is the risk of falling. Tai Chi (TC) is a martial art that has demonstrated improvements in balance control. It uses a series of fluid movements that engage head, neck and trunk rotation while simultaneously reducing base of support. In addition, it has been demonstrated that training older adults by administering unpredictable perturbations to challenge balance better equips them to react successfully in response to balance perturbations. This study aims to determine the potential balance specific benefits …

A New Qualitative Typology To Classify Treading Water Movement Patterns, Christophe Schnitzler, Chris Button, James L. Croft, Ludovic Seifert

Research outputs 2014 to 2021

This study proposes a new qualitative typology that can be used to classify learners treading water into different skill-based categories. To establish the typology, 38 participants were videotaped while treading water and their movement patterns were qualitatively analyzed by two experienced biomechanists. 13 sport science students were then asked to classify eight of the original participants after watching a brief tutorial video about how to use the typology. To examine intra-rater consistency, each participant was presented in a random order three times. Generalizability (G) and Decision (D) studies were performed to estimate the importance variance due to rater, occasion, video …

Hip Abductors And Thigh Muscles Strength Ratios And Their Relation To Electromyography Amplitude During Split Squat And Walking Lunge Exercises, Petr Stastny, James J. Tufano, Michal Lehnert, Artur Golas, Amr Zaatar, Zuzana Xaverova, Adam Maszczyk

Research outputs 2014 to 2021

Background: The hip abductors (HAB), quadriceps (Q) and hamstrings (H) reciprocal strength ratios are predictors of electromyography (EMG) amplitude during load carrying walking at moderate intensity. Therefore, these strength ratios might predict also the EMG during the exercises as walking lunge (WL) or split squat (SSq) at submaximal intensity. Objective: To determine whether the EMG amplitude of vastus mediali (VM), vastus laterali (VL), biceps femoris (BF) and gluteus medius (Gmed) is associated with muscle strength ratio during SSqs and WLs. To determine whether the EMG amplitude differs between individuals with HAB/H ratio above and below one and between individuals with …

Investigating The Effects Of Biochemical And Biophysical Signals On Vascular Smooth Muscle Cell Differentiation, Ruikai Chen

All Dissertations

In blood vessel engineering, an optimal bioartifical scaffold can be characterized as a 3D tubular structure with high porosity for nutrient diffusion and enough mechanical strength to sustain in vivo dynamic environment. The luminal surface of the scaffold is supposed to have a continuous layer of endothelial cell that is ideally non-immunogenic and non-thrombogenic while the media layer of the construct is assigned for the ingrowth of vascular smooth muscle cell which can provide structural integrity and contractility. While reconstructing endothelial cell layer has been at the center of interest in most polymeric vascular replacements related research, growing VSMCs has …

Putting Reins On The Brain. How The Body And Environment Use It, Dobromir Dotov

Journal Articles

Radical embodied cognitive neuroscience (RECN) will probably rely on dynamical systems theory (DST) and complex systems theory for methods and formalism. Yet, there have been plenty of non-radical neurodynamicists out there for quite some time. How much of their work fits with radical embodied cognitive science, what do they need RECN for, and what are the inconsistencies between RECN and established neurodynamics that would have to be resolved? This paper is both theoretical hypothesis and review. First, it provides a brief overview of the typical, purely structural considerations why the central nervous systems (CNS) should be treated as a nonlinear …

Effects Of Yoga On Arm Volume Among Women With Breast Cancer Related Lymphedema: A Pilot Study, Mary Insana Fisher, Betsy Donahoe-Fillmore, Laura Leach, Colleen O'Malley, Cheryl Paeplow, Tess Prescott, Harold L. Merriman

Physical Therapy Faculty Publications

Lymphedema affects 3–58% of survivors of breast cancer and can result in upper extremity impairments. Exercise can be beneficial in managing lymphedema. Yoga practice has been minimally studied for its effects on breast cancer related lymphedema (BCRL). The purpose of this study was to determine the effect of yoga on arm volume, quality of life (QOL), self-reported arm function, and hand grip strength in women with BCRL. Six women with BCRL participated in modified Hatha yoga 3×/week for 8 weeks. Compression sleeves were worn during yoga sessions. Arm volume, QOL, self-reported arm function, and hand grip strength were measured at …

University Of Nebraska At Omaha Biomechanics Research Building Annual Report, Fall 2014, Biomechanics Research Building

Biomechanics Annual Report

This annual report features:

Letter from the Directer; COBRE Grant Press Release

Updates - Our New Building; Visitors; Moving on Up; Why Choose BRB as a Student?; Where Are They Now?; From the Bench to the Market

Projects - Neuroscience; NASA: Stimulation of the Sensory System; Motor Development; Variability Studies; Path Integration; Peripheral Artery Disease and Aging

Other Content - Beyond our Borders; Journal Club; Awards; Faculty Travels; Conferences; NE Science Fest; Campaign for Nebraska

A Comparative Assessment Of Hand Preference In Captive Red Howler Monkeys, Alouatta Seniculus And Yellow-Breasted Capuchin Monkeys, Sapajus Xanthosternos, Nasibah Sfar, Madhur Mangalam, Werner Kaumanns, Mewa Singh

Journal Articles

There are two major theories that attempt to explain hand preference in non-human primates–the ‘task complexity’ theory and the ‘postural origins’ theory. In the present study, we proposed a third hypothesis to explain the evolutionary origin of hand preference in non-human primates, stating that it could have evolved owing to structural and functional adaptations to feeding, which we refer to as the ‘niche structure’ hypothesis. We attempted to explore this hypothesis by comparing hand preference across species that differ in the feeding ecology and niche structure: red howler monkeys, Alouatta seniculus and yellow-breasted capuchin monkeys, Sapajus xanthosternos. The red …

Locomotor Sensory Organization Test: A Novel Paradigm For The Assessment Of Sensory Contributions In Gait, Jung Hung Chien, Diderik-Jan Eikema, Mukul Mukherjee, Nicholas Stergiou

Journal Articles

Feedback based balance control requires the integration of visual, proprioceptive and vestibular input to detect the body’s movement within the environment. When the accuracy of sensory signals is compromised, the system reorganizes the relative contributions through a process of sensory recalibration, for upright postural stability to be maintained. Whereas this process has been studied extensively in standing using the Sensory Organization Test (SOT), less is known about these processes in more dynamic tasks such as locomotion. In the present study, ten healthy young adults performed the six conditions of the traditional SOT to quantify standing postural control when exposed to …

Motor Output Structure In Targeted Aiming: A Mechanistic Model, Dale Lewis, Roger Young, Jeffrey Eder, Andrew B, Slifkin

Undergraduate Research Posters 2014

Studies using a variety of experimental tasks have established that when humans repeatedly produce an action, fluctuations in action output are highest at the lowest frequencies and fluctuation magnitude (power) systematically declines as frequency increases. Such time series structure is termed pink noise. However, the appearance of pink noise seems to be limited to tasks where action is executed in the absence of task-related feedback. A few studies have demonstrated that when action was executed in the presence of task-related feedback, power was evenly distributed across all spectral frequencies—i.e., white noise was revealed. Here, participants produced cyclical aiming movements under …

Locomotor Sensory Organization Test: A Novel Paradigm For The Assessment Of Sensory Contributions In Gait, Jung Hung Chien, Diderik Jan Anthony Eikema, Mukul Mukherjee, Nikolaos Stergiou

Journal Articles

Feedback based balance control requires the integration of visual, proprioceptive and vestibular input to detect the body’s movement within the environment. When the accuracy of sensory signals is compromised, the system reorganizes the relative contributions through a process of sensory recalibration, for upright postural stability to be maintained. Whereas this process has been studied extensively in standing using the Sensory Organization Test (SOT), less is known about these processes in more dynamic tasks such as locomotion. In the present study, ten healthy young adults performed the six conditions of the traditional SOT to quantify standing postural control when exposed to …

Lower Extremity Injury In Female Basketball Players Is Related To A Large Difference In Peak Eversion Torque Between Barefoot And Shod Conditions, Jenna M. Yentes, Max J. Kurz, Nikolaos Stergiou

Journal Articles

Background
The majority of injuries reported in female basketball players are ankle sprains and mechanisms leading to injury have been debated. Investigations into muscular imbalances in barefoot versus shod conditions and their relationship with injury severity have not been performed. The purpose of this study was to investigate the effects of wearing athletic shoes on muscular strength and its relationship to lower extremity injuries, specifically female basketball players due to the high incidence of ankle injuries in this population.

Methods
During pre-season, 11 female collegiate basketball players underwent inversion and eversion muscle strength testing using an isokinetic dynamometer in both …

How Sensitive Is The Deltoid Moment Arm To Joint Center Changes With Rtsa?, David Walker, Allison Kinney, Aimee Struk, Benjamin J. Fregly, Thomas Wright, Scott Banks

Mechanical and Aerospace Engineering Faculty Publications

The goal of this study was to assess the sensitivity of the deltoid muscle moment arms as a function of joint configuration for an existing RTSA subject. High variations were found for all three deltoid components. Variation over the entire abduction arc was greatest in the anterior and lateral deltoid, while the posterior deltoid moment arm was mostly sensitive to joint center changes early in the abduction arc. Moment arm changes of 10-16mm represent a significant amount of the total deltoid moment arm. This means there is an opportunity to dramatically change the deltoid moments arms through surgical placement of …

Deltoid Moment Arms During Abduction: A Subject-Specific Musculoskeletal Modeling Study In Healthy Shoulders And Shoulders With Rtsa, David Walker, Allison Kinney, Aimee Struk, Benjamin J. Fregly, Thomas Wright, Scott Banks

Mechanical and Aerospace Engineering Faculty Publications

Reverse total shoulder arthroplasty (RTSA) is increasingly used in the United States since approval by the FDA in 2003. RTSA relieves pain and restores mobility in arthritic rotator cuff deficient shoulders. Though many advantages of RTSA have been demonstrated, there still are a variety of complications (implant loosening, shoulder impingement, infection, frozen shoulder) making apparent much still is to be learned how RTSA modifies normal shoulder function. The goal of this study was to assess how RTSA affects deltoid muscle moment generating capacity post-surgery using a subjectspecific computational model driven by in vivo kinematic data.

A Novel Approach To Estimation Of Patient-Specific Muscle Strength, David Walker, Allison Kinney, Benjamin J. Fregly, Thomas Wright, Scott Banks

Mechanical and Aerospace Engineering Faculty Publications

Current modeling techniques have been used to model the Reverse Total Shoulder Arthroplasty (RTSA) to account for the geometric changes implemented after RTSA. Though these models have provided insight into the effects of geometric changes from RTSA these is still a limitation of understanding muscle function after RTSA on a patient-specific basis. The goal of this study sought to overcome this limitation by developing an approach to calibrate patient-specific muscle strength for an RTSA subject.

Gaze And Posture Coordinate Differently With The Complexity Of Visual Stimulus Motion, Joshua L. Haworth, Srikant Vallabhajosula, Nikolaos Stergiou

Journal Articles

In this study, we explored whether gaze and posture would exhibit coordination with the motion of a presented visual stimulus, specifically with regard to the complexity of the motion structure. Fourteen healthy adults viewed a set of four visual stimulus motion conditions, in both self-selected and semi-tandem stance, during which the stimulus moved horizontally across a screen, with position updated to follow a sine, chaos, surrogate, or random noise trajectory. Posture was measured using a standard force platform in self-selected and semi-tandem stance conditions while gaze was recorded using image-based eye-tracking equipment. Cross-correlation confirmed the continuous coordination of gaze with …

The Influence Of Auditory-Motor Coupling On Fractal Dynamics In Human Gait, Nathaniel Hunt, Denise Mcgrath, Nikolaos Stergiou

Journal Articles

Humans exhibit an innate ability to synchronize their movements to music. The field of gait rehabilitation has sought to capitalize on this phenomenon by invoking patients to walk in time to rhythmic auditory cues with a view to improving pathological gait. However, the temporal structure of the auditory cue, and hence the temporal structure of the target behavior has not been sufficiently explored. This study reveals the plasticity of auditory-motor coupling in human walking in relation to ‘complex’ auditory cues. The authors demonstrate that auditory-motor coupling can be driven by different coloured auditory noise signals (e.g. white, brown), shifting the …

Evaluation Of The Functional Capabilities Of Fins And Limbs For Moving On Land: Insights Into The Invasion Of Land By Tetrapods, Sandy Kawano

All Dissertations

Transitions to novel habitats present different adaptive challenges, producing captivating examples of how functional innovations of the musculoskeletal system influence phenotypic divergence and adaptive radiations. One intriguing example is the transition from aquatic fishes to tetrapods. Recent technological advances and discoveries of critical fossils have catapulted our understanding on how fishes gave rise to terrestrial vertebrates. Considerable attention has been paid to legged locomotion on land, but given that the first tetrapods were aquatic, limbs did not evolve primarily for terrestriality. How, then, is the locomotor function of limbs different from fins? Extant amphibious fishes demonstrate that fins can be …

Stride Length-Speed Relationship During Body Weight Supported Running, Carmen Chona

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to determine if body weight support influences the stride length-speed relationship. Additionally, the purpose was to determine if impact characteristics of running are influenced by body weight support and speed. Subjects (n=10; 6 female, 4 male) volunteered to participate in this study. All subjects were injury free and were comfortable running on a treadmill for 30 minutes. Subjects ran on a lower body positive (LBPP, Alter-G, G-Trainer) treadmill for 4 conditions of body weight (100, 40, 30 and 20% of body weight) and 4 running speeds (100, 110, 120 and 130% of the preferred …