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Sample records for biomechanical tongue model

  1. Use of a biomechanical tongue model to predict the impact of tongue surgery on speech production

    CERN Document Server

    Buchaillard, Stéphanie; Perrier, Pascal; Payan, Yohan

    2008-01-01

    This paper presents predictions of the consequences of tongue surgery on speech production. For this purpose, a 3D finite element model of the tongue is used that represents this articulator as a deformable structure in which tongue muscles anatomy is realistically described. Two examples of tongue surgery, which are common in the treatment of cancers of the oral cavity, are modelled, namely a hemiglossectomy and a large resection of the mouth floor. In both cases, three kinds of possible reconstruction are simulated, assuming flaps with different stiffness. Predictions are computed for the cardinal vowels /i, a, u/ in the absence of any compensatory strategy, i.e. with the same motor commands as the one associated with the production of these vowels in non-pathological conditions. The estimated vocal tract area functions and the corresponding formants are compared to the ones obtained under normal conditions

  2. Influences of tongue biomechanics on speech movements during the production of velar stop consonants: a modeling study

    CERN Document Server

    Perrier, P; Zandipour, M; Perkell, J; Perrier, Pascal; Payan, Yohan; Zandipour, Majid; Perkell, Joseph

    2003-01-01

    This study explores the following hypothesis: forward looping movements of the tongue that are observed in VCV sequences are due partly to the anatomical arrangement of the tongue muscles and how they are used to produce a velar closure. The study uses an anatomically based 2D biomechanical tongue model. Tissue elastic properties are accounted for in finite-element modeling, and movement is controlled by constant-rate control parameter shifts. Tongue raising and lowering movements are produced by the model with the combined actions of the genioglossus, styloglossus and hyoglossus. Simulations of V1CV2 movements were made, where C is a velar consonant and V is [a], [i] or [u]. If V1 is one of the vowels [a] and [u], the resulting trajectories describe movements that begin to loop forward before consonant closure and continue to slide along the palate during the closure. This prediction is in agreement with classical data published in the literature. If V1 is vowel [i], we observe a small backward movement. Thi...

  3. Modeling the consequences of tongue surgery on tongue mobility

    CERN Document Server

    Buchaillard, Stéphanie; Perrier, Pascal; Payan, Yohan

    2007-01-01

    This paper presents the current achievements of a long term project aiming at predicting and assessing the impact of tongue and mouth floor surgery on tongue mobility. The ultimate objective of this project is the design of a software with which surgeons should be able (1) to design a 3D biomechanical model of the tongue and of the mouth floor that matches the anatomical characteristics of each patient specific oral cavity, (2) to simulate the anatomical changes induced by the surgery and the possible reconstruction, and (3) to quantitatively predict and assess the consequences of these anatomical changes on tongue mobility and speech production after surgery.

  4. Degrees of freedom of tongue movements in speech may be constrained by biomechanics

    CERN Document Server

    Perrier, Pascal; Payan, Yohan; Zandipour, Majid; Guenther, Franck; Khalighi, Ali

    2007-01-01

    A number of studies carried out on different languages have found that tongue movements in speech are made along two primary degrees of freedom (d.f.s): the high-front to low-back axis and the high-back to low-front axis. We explore the hypothesis that these two main d.f.s could find their origins in the physical properties of the vocal tract. A large set of tongue shapes was generated with a biomechanical tongue model using a Monte-Carlo method to thoroughly sample the muscle control space. The resulting shapes were analyzed with PCA. The first two factors explain 84% of the variance, and they are similar to the two experimentally observed d.f.s. This finding suggests that the d.f.s. are not speech-specific, and that speech takes advantage of biomechanically based tongue properties to form different sounds.

  5. Computational modeling in biomechanics

    CERN Document Server

    Mofrad, Mohammad

    2010-01-01

    This book provides a glimpse of the diverse and important roles that modern computational technology is playing in various areas of biomechanics. It includes unique chapters on ab initio quantum mechanical, molecular dynamic and scale coupling methods..

  6. A 3D biomechanical vocal tract model to study speech production control: How to take into account the gravity?

    CERN Document Server

    Buchaillard, S; Payan, Y; Buchaillard, St\\'{e}phanie; Perrier, Pascal; Payan, Yohan

    2007-01-01

    This paper presents a modeling study of the way speech motor control can deal with gravity to achieve steady-state tongue positions. It is based on simulations carried out with the 3D biomechanical tongue model developed at ICP, which is now controlled with the Lambda model (Equilibrium-Point Hypothesis). The influence of short-delay orosensory feedback on posture stability is assessed by testing different muscle force/muscle length relationships (Invariant Characteristics). Muscle activation patterns necessary to maintain the tongue in a schwa position are proposed, and the relations of head position, tongue shape and muscle activations are analyzed.

  7. Multiscale modeling methods in biomechanics.

    Science.gov (United States)

    Bhattacharya, Pinaki; Viceconti, Marco

    2017-01-19

    More and more frequently, computational biomechanics deals with problems where the portion of physical reality to be modeled spans over such a large range of spatial and temporal dimensions, that it is impossible to represent it as a single space-time continuum. We are forced to consider multiple space-time continua, each representing the phenomenon of interest at a characteristic space-time scale. Multiscale models describe a complex process across multiple scales, and account for how quantities transform as we move from one scale to another. This review offers a set of definitions for this emerging field, and provides a brief summary of the most recent developments on multiscale modeling in biomechanics. Of all possible perspectives, we chose that of the modeling intent, which vastly affect the nature and the structure of each research activity. To the purpose we organized all papers reviewed in three categories: 'causal confirmation,' where multiscale models are used as materializations of the causation theories; 'predictive accuracy,' where multiscale modeling is aimed to improve the predictive accuracy; and 'determination of effect,' where multiscale modeling is used to model how a change at one scale manifests in an effect at another radically different space-time scale. Consistent with how the volume of computational biomechanics research is distributed across application targets, we extensively reviewed papers targeting the musculoskeletal and the cardiovascular systems, and covered only a few exemplary papers targeting other organ systems. The review shows a research subdomain still in its infancy, where causal confirmation papers remain the most common. For further resources related to this article, please visit the WIREs website.

  8. Modeling spinal cord biomechanics

    Science.gov (United States)

    Luna, Carlos; Shah, Sameer; Cohen, Avis; Aranda-Espinoza, Helim

    2012-02-01

    Regeneration after spinal cord injury is a serious health issue and there is no treatment for ailing patients. To understand regeneration of the spinal cord we used a system where regeneration occurs naturally, such as the lamprey. In this work, we analyzed the stress response of the spinal cord to tensile loading and obtained the mechanical properties of the cord both in vitro and in vivo. Physiological measurements showed that the spinal cord is pre-stressed to a strain of 10%, and during sinusoidal swimming, there is a local strain of 5% concentrated evenly at the mid-body and caudal sections. We found that the mechanical properties are homogeneous along the body and independent of the meninges. The mechanical behavior of the spinal cord can be characterized by a non-linear viscoelastic model, described by a modulus of 20 KPa for strains up to 15% and a modulus of 0.5 MPa for strains above 15%, in agreement with experimental data. However, this model does not offer a full understanding of the behavior of the spinal cord fibers. Using polymer physics we developed a model that relates the stress response as a function of the number of fibers.

  9. A soft biomimetic tongue: model reconstruction and motion tracking

    Science.gov (United States)

    Lu, Xuanming; Xu, Weiliang; Li, Xiaoning

    2016-04-01

    A bioinspired robotic tongue which is actuated by a network of compressed air is proposed for the purpose of mimicking the movements of human tongue. It can be applied in the fields such as medical science and food engineering. The robotic tongue is made of two kinds of silicone rubber Ecoflex 0030 and PDMS with the shape simplified from real human tongue. In order to characterize the robotic tongue, a series of experiments were carried out. Laser scan was applied to reconstruct the static model of robotic tongue when it was under pressurization. After each scan, the robotic tongue was scattered into dense points in the same 3D coordinate system and the coordinates of each point were recorded. Motion tracking system (OptiTrack) was used to track and record the whole process of deformation dynamically during the loading and unloading phase. In the experiments, five types of deformation were achieved including roll-up, roll-down, elongation, groove and twist. Utilizing the discrete points generated by laser scan, the accurate parameterized outline of robotic tongue under different pressure was obtained, which could help demonstrate the static characteristic of robotic tongue. The precise deformation process under one pressure was acquired through the OptiTrack system which contains a series of digital cameras, markers on the robotic tongue and a set of hardware and software for data processing. By means of tracking and recording different process of deformation under different pressure, the dynamic characteristic of robotic tongue could be achieved.

  10. Multiscale modeling in biomechanics and mechanobiology

    CERN Document Server

    Hwang, Wonmuk; Kuhl, Ellen

    2015-01-01

    Presenting a state-of-the-art overview of theoretical and computational models that link characteristic biomechanical phenomena, this book provides guidelines and examples for creating multiscale models in representative systems and organisms. It develops the reader's understanding of and intuition for multiscale phenomena in biomechanics and mechanobiology, and introduces a mathematical framework and computational techniques paramount to creating predictive multiscale models.   Biomechanics involves the study of the interactions of physical forces with biological systems at all scales – including molecular, cellular, tissue and organ scales. The emerging field of mechanobiology focuses on the way that cells produce and respond to mechanical forces – bridging the science of mechanics with the disciplines of genetics and molecular biology. Linking disparate spatial and temporal scales using computational techniques is emerging as a key concept in investigating some of the complex problems underlying these...

  11. Identifying nonlinear biomechanical models by multicriteria analysis

    Science.gov (United States)

    Srdjevic, Zorica; Cveticanin, Livija

    2012-02-01

    In this study, the methodology developed by Srdjevic and Cveticanin (International Journal of Industrial Ergonomics 34 (2004) 307-318) for the nonbiased (objective) parameter identification of the linear biomechanical model exposed to vertical vibrations is extended to the identification of n-degree of freedom (DOF) nonlinear biomechanical models. The dynamic performance of the n-DOF nonlinear model is described in terms of response functions in the frequency domain, such as the driving-point mechanical impedance and seat-to-head transmissibility function. For randomly generated parameters of the model, nonlinear equations of motion are solved using the Runge-Kutta method. The appropriate data transformation from the time-to-frequency domain is performed by a discrete Fourier transformation. Squared deviations of the response functions from the target values are used as the model performance evaluation criteria, thus shifting the problem into the multicriteria framework. The objective weights of criteria are obtained by applying the Shannon entropy concept. The suggested methodology is programmed in Pascal and tested on a 4-DOF nonlinear lumped parameter biomechanical model. The identification process over the 2000 generated sets of parameters lasts less than 20 s. The model response obtained with the imbedded identified parameters correlates well with the target values, therefore, justifying the use of the underlying concept and the mathematical instruments and numerical tools applied. It should be noted that the identified nonlinear model has an improved accuracy of the biomechanical response compared to the accuracy of a linear model.

  12. Biomedical Imaging and Computational Modeling in Biomechanics

    CERN Document Server

    Iacoviello, Daniela

    2013-01-01

    This book collects the state-of-art and new trends in image analysis and biomechanics. It covers a wide field of scientific and cultural topics, ranging from remodeling of bone tissue under the mechanical stimulus up to optimizing the performance of sports equipment, through the patient-specific modeling in orthopedics, microtomography and its application in oral and implant research, computational modeling in the field of hip prostheses, image based model development and analysis of the human knee joint, kinematics of the hip joint, micro-scale analysis of compositional and mechanical properties of dentin, automated techniques for cervical cell image analysis, and iomedical imaging and computational modeling in cardiovascular disease.   The book will be of interest to researchers, Ph.D students, and graduate students with multidisciplinary interests related to image analysis and understanding, medical imaging, biomechanics, simulation and modeling, experimental analysis.

  13. Supplementing biomechanical modeling with EMG analysis

    Science.gov (United States)

    Lewandowski, Beth; Jagodnik, Kathleen; Crentsil, Lawton; Humphreys, Bradley; Funk, Justin; Gallo, Christopher; Thompson, William; DeWitt, John; Perusek, Gail

    2016-01-01

    It is well established that astronauts experience musculoskeletal deconditioning when exposed to microgravity environments for long periods of time. Spaceflight exercise is used to counteract these effects, and the Advanced Resistive Exercise Device (ARED) on the International Space Station (ISS) has been effective in minimizing musculoskeletal losses. However, the exercise devices of the new exploration vehicles will have requirements of limited mass, power and volume. Because of these limitations, there is a concern that the exercise devices will not be as effective as ARED in maintaining astronaut performance. Therefore, biomechanical modeling is being performed to provide insight on whether the small Multi-Purpose Crew Vehicle (MPCV) device, which utilizes a single-strap design, will provide sufficient physiological loading to maintain musculoskeletal performance. Electromyography (EMG) data are used to supplement the biomechanical model results and to explore differences in muscle activation patterns during exercises using different loading configurations.

  14. A Biomechanical Modeling Guided CBCT Estimation Technique.

    Science.gov (United States)

    Zhang, You; Tehrani, Joubin Nasehi; Wang, Jing

    2017-02-01

    Two-dimensional-to-three-dimensional (2D-3D) deformation has emerged as a new technique to estimate cone-beam computed tomography (CBCT) images. The technique is based on deforming a prior high-quality 3D CT/CBCT image to form a new CBCT image, guided by limited-view 2D projections. The accuracy of this intensity-based technique, however, is often limited in low-contrast image regions with subtle intensity differences. The solved deformation vector fields (DVFs) can also be biomechanically unrealistic. To address these problems, we have developed a biomechanical modeling guided CBCT estimation technique (Bio-CBCT-est) by combining 2D-3D deformation with finite element analysis (FEA)-based biomechanical modeling of anatomical structures. Specifically, Bio-CBCT-est first extracts the 2D-3D deformation-generated displacement vectors at the high-contrast anatomical structure boundaries. The extracted surface deformation fields are subsequently used as the boundary conditions to drive structure-based FEA to correct and fine-tune the overall deformation fields, especially those at low-contrast regions within the structure. The resulting FEA-corrected deformation fields are then fed back into 2D-3D deformation to form an iterative loop, combining the benefits of intensity-based deformation and biomechanical modeling for CBCT estimation. Using eleven lung cancer patient cases, the accuracy of the Bio-CBCT-est technique has been compared to that of the 2D-3D deformation technique and the traditional CBCT reconstruction techniques. The accuracy was evaluated in the image domain, and also in the DVF domain through clinician-tracked lung landmarks.

  15. Simulations of the consequences of tongue surgery on tongue mobility: implications for speech production in post-surgery conditions

    CERN Document Server

    Buchaillard, Stéphanie; Perrier, Pascal; Payan, Yohan

    2007-01-01

    This paper presents simulations of the impact of tongue surgery on tongue movements and on speech articulation. For this, a 3D biomechanical Finite Element (FE) model of the tongue is used. Muscles are represented within the FE structure by specific subsets of elements. The tongue model is inserted in the upper airways including jaw, palate and pharyngeal walls. Two examples of tongue surgery, which are quite common in the treatment of cancers of the oral cavity are modelled: hemiglossectomy and large resection of the mouth floor. Three kinds of reconstruction are also modelled, assuming flaps with a low, medium or high stiffnesses. The impact of the surgery without any reconstruction and with the three different reconstructions is quantitatively measured and compared during simulated speech production sequences. More precisely, differences in global 3D tongue shape and in velocity patterns during tongue displacements are evaluated.

  16. Biomechanics trends in modeling and simulation

    CERN Document Server

    Ogden, Ray

    2017-01-01

    The book presents a state-of-the-art overview of biomechanical and mechanobiological modeling and simulation of soft biological tissues. Seven well-known scientists working in that particular field discuss topics such as biomolecules, networks and cells as well as failure, multi-scale, agent-based, bio-chemo-mechanical and finite element models appropriate for computational analysis. Applications include arteries, the heart, vascular stents and valve implants as well as adipose, brain, collagenous and engineered tissues. The mechanics of the whole cell and sub-cellular components as well as the extracellular matrix structure and mechanotransduction are described. In particular, the formation and remodeling of stress fibers, cytoskeletal contractility, cell adhesion and the mechanical regulation of fibroblast migration in healing myocardial infarcts are discussed. The essential ingredients of continuum mechanics are provided. Constitutive models of fiber-reinforced materials with an emphasis on arterial walls ...

  17. Soft Tissue Biomechanical Modeling for Computer Assisted Surgery

    CERN Document Server

    2012-01-01

      This volume focuses on the biomechanical modeling of biological tissues in the context of Computer Assisted Surgery (CAS). More specifically, deformable soft tissues are addressed since they are the subject of the most recent developments in this field. The pioneering works on this CAS topic date from the 1980's, with applications in orthopaedics and biomechanical models of bones. More recently, however, biomechanical models of soft tissues have been proposed since most of the human body is made of soft organs that can be deformed by the surgical gesture. Such models are much more complicated to handle since the tissues can be subject to large deformations (non-linear geometrical framework) as well as complex stress/strain relationships (non-linear mechanical framework). Part 1 of the volume presents biomechanical models that have been developed in a CAS context and used during surgery. This is particularly new since most of the soft tissues models already proposed concern Computer Assisted Planning, with ...

  18. Progress in animation of an EMA-controlled tongue model for acoustic-visual speech synthesis

    CERN Document Server

    Steiner, Ingmar

    2012-01-01

    We present a technique for the animation of a 3D kinematic tongue model, one component of the talking head of an acoustic-visual (AV) speech synthesizer. The skeletal animation approach is adapted to make use of a deformable rig controlled by tongue motion capture data obtained with electromagnetic articulography (EMA), while the tongue surface is extracted from volumetric magnetic resonance imaging (MRI) data. Initial results are shown and future work outlined.

  19. A biomechanical modeling study of the effects of the orbicularis oris muscle and jaw posture on lip shape

    CERN Document Server

    Stavness, Ian; Perrier, Pascal; Demolin, Didier; Payan, Yohan

    2013-01-01

    Purpose: The authors' general aim is to use biomechanical models of speech articulators to explore how possible variations in anatomical structure contribute to differences in articulatory strategies and phone systems across human populations. Specifically, they investigated 2 issues: (a) the link between lip muscle anatomy and variability in lip gestures and (b) the constraints of coupled lip/jaw biomechanics on jaw posture in labial sounds. Method: The authors used a model coupling the jaw, tongue, and face. First, the influence of the orbicularis oris (OO) anatomical implementation was analyzed by assessing how changes in depth (from epidermis to the skull) and peripheralness (proximity to the lip horn center) affected lip shaping. Second, the capability of the lip/jaw system to generate protrusion and rounding, or labial closure, was evaluated for different jaw heights. Results: Results showed that a peripheral and moderately deep OO implementation is most appropriate for protrusion and rounding; a superf...

  20. Use of deterministic models in sports and exercise biomechanics research.

    Science.gov (United States)

    Chow, John W; Knudson, Duane V

    2011-09-01

    A deterministic model is a modeling paradigm that determines the relationships between a movement outcome measure and the biomechanical factors that produce such a measure. This review provides an overview of the use of deterministic models in biomechanics research, a historical summary of this research, and an analysis of the advantages and disadvantages of using deterministic models. The deterministic model approach has been utilized in technique analysis over the last three decades, especially in swimming, athletics field events, and gymnastics. In addition to their applications in sports and exercise biomechanics, deterministic models have been applied successfully in research on selected motor skills. The advantage of the deterministic model approach is that it helps to avoid selecting performance or injury variables arbitrarily and to provide the necessary theoretical basis for examining the relative importance of various factors that influence the outcome of a movement task. Several disadvantages of deterministic models, such as the use of subjective measures for the performance outcome, were discussed. It is recommended that exercise and sports biomechanics scholars should consider using deterministic models to help identify meaningful dependent variables in their studies.

  1. Biomechanically Excited SMD Model of a Walking Pedestrian

    DEFF Research Database (Denmark)

    Zhang, Mengshi; Georgakis, Christos T.; Chen, Jun

    2016-01-01

    estimated from a known walking frequency and the pedestrian's weight, assuming that pedestrians always walk in displacement resonance and retain a constant damping ratio of 0.3. Thus, biomechanical forces were extracted using the measured SMD dynamic responses and the estimated SMD parameters. Extracted...... of biomechanical forces, was used to model a pedestrian for application in vertical human-structure interaction (HSI). Tests were undertaken in a gait laboratory, where a three-dimensional motion-capture system was used to record a pedestrian's walking motions at various frequencies. The motion-capture system...... produced the pedestrian's center of mass (COM) trajectories from the captured motion markers. The vertical COM trajectory was approximated to be the pedestrian SMD dynamic responses under the excitation of biomechanical forces. SMD model parameters of a pedestrian for a specific walking frequency were...

  2. Quantitative modelling of the biomechanics of the avian syrinx

    NARCIS (Netherlands)

    Elemans, C.P.H.; Larsen, O.N.; Hoffmann, M.R.; Leeuwen, van J.L.

    2003-01-01

    We review current quantitative models of the biomechanics of bird sound production. A quantitative model of the vocal apparatus was proposed by Fletcher (1988). He represented the syrinx (i.e. the portions of the trachea and bronchi with labia and membranes) as a single membrane. This membrane acts

  3. Quantitative modelling of the biomechanics of the avian syrinx

    DEFF Research Database (Denmark)

    Elemans, Coen P. H.; Larsen, Ole Næsbye; Hoffmann, Marc R.

    2003-01-01

    We review current quantitative models of the biomechanics of bird sound production. A quantitative model of the vocal apparatus was proposed by Fletcher (1988). He represented the syrinx (i.e. the portions of the trachea and bronchi with labia and membranes) as a single membrane. This membrane acts...

  4. Computational biomechanics for medicine imaging, modeling and computing

    CERN Document Server

    Doyle, Barry; Wittek, Adam; Nielsen, Poul; Miller, Karol

    2016-01-01

    The Computational Biomechanics for Medicine titles provide an opportunity for specialists in computational biomechanics to present their latest methodologies and advancements. This volume comprises eighteen of the newest approaches and applications of computational biomechanics, from researchers in Australia, New Zealand, USA, UK, Switzerland, Scotland, France and Russia. Some of the interesting topics discussed are: tailored computational models; traumatic brain injury; soft-tissue mechanics; medical image analysis; and clinically-relevant simulations. One of the greatest challenges facing the computational engineering community is to extend the success of computational mechanics to fields outside traditional engineering, in particular to biology, the biomedical sciences, and medicine. We hope the research presented within this book series will contribute to overcoming this grand challenge.

  5. Activity Recognition Using Biomechanical Model Based Pose Estimation

    OpenAIRE

    Reiss, Attila; Hendeby, Gustaf; Bleser, Gabriele; Stricker, Didier

    2010-01-01

    In this paper, a novel activity recognition method based on signal-oriented and model-based features is presented. The model-based features are calculated from shoulder and elbow joint angles and torso orientation, provided by upper-body pose estimation based on a biomechanical body model. The recognition performance of signal-oriented and model-based features is compared within this paper, and the potential of improving recognition accuracy by combining the two approaches is proved: the accu...

  6. An observational model for biomechanical assessment of sprint kayaking technique.

    Science.gov (United States)

    McDonnell, Lisa K; Hume, Patria A; Nolte, Volker

    2012-11-01

    Sprint kayaking stroke phase descriptions for biomechanical analysis of technique vary among kayaking literature, with inconsistencies not conducive for the advancement of biomechanics applied service or research. We aimed to provide a consistent basis for the categorisation and analysis of sprint kayak technique by proposing a clear observational model. Electronic databases were searched using key words kayak, sprint, technique, and biomechanics, with 20 sources reviewed. Nine phase-defining positions were identified within the kayak literature and were divided into three distinct types based on how positions were defined: water-contact-defined positions, paddle-shaft-defined positions, and body-defined positions. Videos of elite paddlers from multiple camera views were reviewed to determine the visibility of positions used to define phases. The water-contact-defined positions of catch, immersion, extraction, and release were visible from multiple camera views, therefore were suitable for practical use by coaches and researchers. Using these positions, phases and sub-phases were created for a new observational model. We recommend that kayaking data should be reported using single strokes and described using two phases: water and aerial. For more detailed analysis without disrupting the basic two-phase model, a four-sub-phase model consisting of entry, pull, exit, and aerial sub-phases should be used.

  7. Graphic-based musculoskeletal model for biomechanical analyses and animation.

    Science.gov (United States)

    Chao, Edmund Y S

    2003-04-01

    The ability to combine physiology and engineering analyses with computer sciences has opened the door to the possibility of creating the 'Virtual Human' reality. This paper presents a broad foundation for a full-featured biomechanical simulator for the human musculoskeletal system physiology. This simulation technology unites the expertise in biomechanical analysis and graphic modeling to investigate joint and connective tissue mechanics at the structural level and to visualize the results in both static and animated forms together with the model. Adaptable anatomical models including prosthetic implants and fracture fixation devices and a robust computational infrastructure for static, kinematic, kinetic, and stress analyses under varying boundary and loading conditions are incorporated on a common platform, the VIMS (Virtual Interactive Musculoskeletal System). Within this software system, a manageable database containing long bone dimensions, connective tissue material properties and a library of skeletal joint system functional activities and loading conditions are also available and they can easily be modified, updated and expanded. Application software is also available to allow end-users to perform biomechanical analyses interactively. This paper details the design, capabilities, and features of the VIMS development at Johns Hopkins University, an effort possible only through academic and commercial collaborations. Examples using these models and the computational algorithms in a virtual laboratory environment are used to demonstrate the utility of this unique database and simulation technology. This integrated system will impact on medical education, basic research, device development and application, and clinical patient care related to musculoskeletal diseases, trauma, and rehabilitation.

  8. Probabilistic Modeling of Intracranial Pressure Effects on Optic Nerve Biomechanics

    Science.gov (United States)

    Ethier, C. R.; Feola, Andrew J.; Raykin, Julia; Myers, Jerry G.; Nelson, Emily S.; Samuels, Brian C.

    2016-01-01

    Altered intracranial pressure (ICP) is involved/implicated in several ocular conditions: papilledema, glaucoma and Visual Impairment and Intracranial Pressure (VIIP) syndrome. The biomechanical effects of altered ICP on optic nerve head (ONH) tissues in these conditions are uncertain but likely important. We have quantified ICP-induced deformations of ONH tissues, using finite element (FE) and probabilistic modeling (Latin Hypercube Simulations (LHS)) to consider a range of tissue properties and relevant pressures.

  9. Multiscale computer modeling in biomechanics and biomedical engineering

    CERN Document Server

    2013-01-01

    This book reviews the state-of-the-art in multiscale computer modeling, in terms of both accomplishments and challenges. The information in the book is particularly useful for biomedical engineers, medical physicists and researchers in systems biology, mathematical biology, micro-biomechanics and biomaterials who are interested in how to bridge between traditional biomedical engineering work at the organ and tissue scales, and the newer arenas of cellular and molecular bioengineering.

  10. A novel biomechanical model assessing continuous orthodontic archwire activation

    Science.gov (United States)

    Canales, Christopher; Larson, Matthew; Grauer, Dan; Sheats, Rose; Stevens, Clarke; Ko, Ching-Chang

    2013-01-01

    Objective The biomechanics of a continuous archwire inserted into multiple orthodontic brackets is poorly understood. The purpose of this research was to apply the birth-death technique to simulate insertion of an orthodontic wire and consequent transfer of forces to the dentition in an anatomically accurate model. Methods A digital model containing the maxillary dentition, periodontal ligament (PDL), and surrounding bone was constructed from human computerized tomography data. Virtual brackets were placed on four teeth (central and lateral incisors, canine and first premolar), and a steel archwire (0.019″ × 0.025″) with a 0.5 mm step bend to intrude the lateral incisor was virtually inserted into the bracket slots. Forces applied to the dentition and surrounding structures were simulated utilizing the birth-death technique. Results The goal of simulating a complete bracket-wire system on accurate anatomy including multiple teeth was achieved. Orthodontic force delivered by the wire-bracket interaction was: central incisor 19.1 N, lateral incisor 21.9 N, and canine 19.9 N. Loading the model with equivalent point forces showed a different stress distribution in the PDL. Conclusions The birth-death technique proved to be a useful biomechanical simulation method for placement of a continuous archwire in orthodontic brackets. The ability to view the stress distribution throughout proper anatomy and appliances advances understanding of orthodontic biomechanics. PMID:23374936

  11. Mother Tongue Use in Task-Based Language Teaching Model

    Science.gov (United States)

    Hung, Nguyen Viet

    2012-01-01

    Researches of English language teaching (ELT) have focused on using mother tongue (L1) for years. The proliferation of task-based language teaching (TBLT) has been also occurred. Considerable findings have been made in the existing literature of the two fields; however, no mentions have been made in the combination of these two ELT aspects, i.e.,…

  12. Human body modeling in injury biomechanics

    NARCIS (Netherlands)

    Happee, R.; Morsink, P.L.J.; Horst, M.J. van der; Wismans, J.S.H.M.

    1999-01-01

    Mathematical modelling is widely used for crash-safety research and design. However, most occupant models used in crash simulations are based on crash dummies and thereby inherit their apparent limitations. This paper describes a mathematical model of the real human body for impact loading. A combin

  13. Computer Models in Biomechanics From Nano to Macro

    CERN Document Server

    Kuhl, Ellen

    2013-01-01

    This book contains a collection of papers that were presented at the IUTAM Symposium on “Computer Models in Biomechanics: From Nano to Macro” held at Stanford University, California, USA, from August 29 to September 2, 2011. It contains state-of-the-art papers on: - Protein and Cell Mechanics: coarse-grained model for unfolded proteins, collagen-proteoglycan structural interactions in the cornea, simulations of cell behavior on substrates - Muscle Mechanics: modeling approaches for Ca2+–regulated smooth muscle contraction, smooth muscle modeling using continuum thermodynamical frameworks, cross-bridge model describing the mechanoenergetics of actomyosin interaction, multiscale skeletal muscle modeling - Cardiovascular Mechanics: multiscale modeling of arterial adaptations by incorporating molecular mechanisms, cardiovascular tissue damage, dissection properties of aortic aneurysms, intracranial aneurysms, electromechanics of the heart, hemodynamic alterations associated with arterial remodeling followin...

  14. Biomechanical models to simulate consequences of maxillofacial surgery

    CERN Document Server

    Payan, Y; Pelorson, X; Vilain, C; Levy, P; Luboz, V; Perrier, P; Payan, Yohan; Chabanas, Matthieu; Pelorson, Xavier; Vilain, Coriandre; Levy, Patrick; Luboz, Vincent; Perrier, Pascal

    2002-01-01

    This paper presents the biomechanical finite element models that have been developed in the framework of the computer-assisted maxillofacial surgery. After a brief overview of the continuous elastic modelling method, two models are introduced and their use for computer-assisted applications discussed. The first model deals with orthognathic surgery and aims at predicting the facial consequences of maxillary and mandibular osteotomies. For this, a generic three-dimensional model of the face is automatically adapted to the morphology of the patient by the mean of elastic registration. Qualitative simulations of the consequences of an osteotomy of the mandible can thus be provided. The second model addresses the Sleep Apnoea Syndrome. Its aim is to develop a complete modelling of the interaction between airflow and upper airways walls during respiration. Dynamical simulations of the interaction during a respiratory cycle are computed and compared with observed phenomena.

  15. Quantitative diagnosis of tongue cancer from histological images in an animal model

    Science.gov (United States)

    Lu, Guolan; Qin, Xulei; Wang, Dongsheng; Muller, Susan; Zhang, Hongzheng; Chen, Amy; Chen, Zhuo G.; Fei, Baowei

    2016-03-01

    We developed a chemically-induced oral cancer animal model and a computer aided method for tongue cancer diagnosis. The animal model allows us to monitor the progress of the lesions over time. Tongue tissue dissected from mice was sent for histological processing. Representative areas of hematoxylin and eosin stained tissue from tongue sections were captured for classifying tumor and non-tumor tissue. The image set used in this paper consisted of 214 color images (114 tumor and 100 normal tissue samples). A total of 738 color, texture, morphometry and topology features were extracted from the histological images. The combination of image features from epithelium tissue and its constituent nuclei and cytoplasm has been demonstrated to improve the classification results. With ten iteration nested cross validation, the method achieved an average sensitivity of 96.5% and a specificity of 99% for tongue cancer detection. The next step of this research is to apply this approach to human tissue for computer aided diagnosis of tongue cancer.

  16. Longitudinal modeling in sports: young swimmers' performance and biomechanics profile.

    Science.gov (United States)

    Morais, Jorge E; Marques, Mário C; Marinho, Daniel A; Silva, António J; Barbosa, Tiago M

    2014-10-01

    New theories about dynamical systems highlight the multi-factorial interplay between determinant factors to achieve higher sports performances, including in swimming. Longitudinal research does provide useful information on the sportsmen's changes and how training help him to excel. These questions may be addressed in one single procedure such as latent growth modeling. The aim of the study was to model a latent growth curve of young swimmers' performance and biomechanics over a season. Fourteen boys (12.33 ± 0.65 years-old) and 16 girls (11.15 ± 0.55 years-old) were evaluated. Performance, stroke frequency, speed fluctuation, arm's propelling efficiency, active drag, active drag coefficient and power to overcome drag were collected in four different moments of the season. Latent growth curve modeling was computed to understand the longitudinal variation of performance (endogenous variables) over the season according to the biomechanics (exogenous variables). Latent growth curve modeling showed a high inter- and intra-subject variability in the performance growth. Gender had a significant effect at the baseline and during the performance growth. In each evaluation moment, different variables had a meaningful effect on performance (M1: Da, β = -0.62; M2: Da, β = -0.53; M3: η(p), β = 0.59; M4: SF, β = -0.57; all P performance over time. Different variables were the main responsible for the performance improvement. A gender gap, intra- and inter-subject variability was verified.

  17. Fissured Tongue

    Science.gov (United States)

    ... 2020 Annual Meeting Orlando, FL Our Partners Fissured Tongue The term fissured tongue describes the finding of multiple small furrows or grooves on the dorsal (top) surface of the tongue. These fissures can be shallow or deep, single ...

  18. Tongue biopsy

    Science.gov (United States)

    Biopsy - tongue ... A tongue biopsy can be done using a needle. You will get numbing medicine at the place where the ... provider will gently stick the needle into the tongue and remove a tiny piece of tissue. Some ...

  19. Your Tongue

    Science.gov (United States)

    ... Room? What Happens in the Operating Room? Your Tongue KidsHealth > For Kids > Your Tongue Print A A ... sing. And don't forget talking and tasting! Tongue Twister Has anyone ever told you that the ...

  20. Stents: Biomechanics, Biomaterials, and Insights from Computational Modeling.

    Science.gov (United States)

    Karanasiou, Georgia S; Papafaklis, Michail I; Conway, Claire; Michalis, Lampros K; Tzafriri, Rami; Edelman, Elazer R; Fotiadis, Dimitrios I

    2017-04-01

    Coronary stents have revolutionized the treatment of coronary artery disease. Improvement in clinical outcomes requires detailed evaluation of the performance of stent biomechanics and the effectiveness as well as safety of biomaterials aiming at optimization of endovascular devices. Stents need to harmonize the hemodynamic environment and promote beneficial vessel healing processes with decreased thrombogenicity. Stent design variables and expansion properties are critical for vessel scaffolding. Drug-elution from stents, can help inhibit in-stent restenosis, but adds further complexity as drug release kinetics and coating formulations can dominate tissue responses. Biodegradable and bioabsorbable stents go one step further providing complete absorption over time governed by corrosion and erosion mechanisms. The advances in computing power and computational methods have enabled the application of numerical simulations and the in silico evaluation of the performance of stent devices made up of complex alloys and bioerodible materials in a range of dimensions and designs and with the capacity to retain and elute bioactive agents. This review presents the current knowledge on stent biomechanics, stent fatigue as well as drug release and mechanisms governing biodegradability focusing on the insights from computational modeling approaches.

  1. Evaluation of a laboratory model of human head impact biomechanics.

    Science.gov (United States)

    Hernandez, Fidel; Shull, Peter B; Camarillo, David B

    2015-09-18

    This work describes methodology for evaluating laboratory models of head impact biomechanics. Using this methodology, we investigated: how closely does twin-wire drop testing model head rotation in American football impacts? Head rotation is believed to cause mild traumatic brain injury (mTBI) but helmet safety standards only model head translations believed to cause severe TBI. It is unknown whether laboratory head impact models in safety standards, like twin-wire drop testing, reproduce six degree-of-freedom (6DOF) head impact biomechanics that may cause mTBI. We compared 6DOF measurements of 421 American football head impacts to twin-wire drop tests at impact sites and velocities weighted to represent typical field exposure. The highest rotational velocities produced by drop testing were the 74th percentile of non-injury field impacts. For a given translational acceleration level, drop testing underestimated field rotational acceleration by 46% and rotational velocity by 72%. Primary rotational acceleration frequencies were much larger in drop tests (~100 Hz) than field impacts (~10 Hz). Drop testing was physically unable to produce acceleration directions common in field impacts. Initial conditions of a single field impact were highly resolved in stereo high-speed video and reconstructed in a drop test. Reconstruction results reflected aggregate trends of lower amplitude rotational velocity and higher frequency rotational acceleration in drop testing, apparently due to twin-wire constraints and the absence of a neck. These results suggest twin-wire drop testing is limited in modeling head rotation during impact, and motivate continued evaluation of head impact models to ensure helmets are tested under conditions that may cause mTBI.

  2. Biomechanics of epithelial cell islands analyzed by modeling and experimentation

    CERN Document Server

    Coburn, Luke; Noppe, Adrian; Caldwell, Benjamin J; Moussa, Elliott; Yap, Chloe; Priya, Rashmi; Lobaskin, Vladimir; Roberts, Anthony P; Yap, Alpha S; Neufeld, Zoltan; Gomez, Guillermo A

    2016-01-01

    We generated a new computational approach to analyze the biomechanics of epithelial cell islands that combines both vertex and contact-inhibition-of-locomotion models to include both cell-cell and cell-substrate adhesion. Examination of the distribution of cell protrusions (adhesion to the substrate) in the model predicted high order profiles of cell organization that agree with those previously seen experimentally. Cells acquired an asymmetric distribution of protrusions (and traction forces) that decreased when moving from the edge to the island center. Our in silico analysis also showed that tension on cell-cell junctions (and monolayer stress) is not homogeneous across the island. Instead it is higher at the island center and scales up with island size, which we confirmed experimentally using laser ablation assays and immunofluorescence. Moreover, our approach has the minimal elements necessary to reproduce mechanical crosstalk between both cell-cell and cell substrate adhesion systems. We found that an i...

  3. Experimental model for civilian ballistic brain injury biomechanics quantification.

    Science.gov (United States)

    Zhang, Jiangyue; Yoganandan, Narayan; Pintar, Frank A; Guan, Yabo; Gennarelli, Thomas A

    2007-01-01

    Biomechanical quantification of projectile penetration using experimental head models can enhance the understanding of civilian ballistic brain injury and advance treatment. Two of the most commonly used handgun projectiles (25-cal, 275 m/s and 9 mm, 395 m/s) were discharged to spherical head models with gelatin and Sylgard simulants. Four ballistic pressure transducers recorded temporal pressure distributions at 308kHz, and temporal cavity dynamics were captured at 20,000 frames/second (fps) using high-speed digital video images. Pressures ranged from 644.6 to -92.8 kPa. Entry pressures in gelatin models were higher than exit pressures, whereas in Sylgard models entry pressures were lower or equivalent to exit pressures. Gelatin responded with brittle-type failure, while Sylgard demonstrated a ductile pattern through formation of micro-bubbles along projectile path. Temporary cavities in Sylgard models were 1.5-2x larger than gelatin models. Pressures in Sylgard models were more sensitive to projectile velocity and diameter increase, indicating Sylgard was more rate sensitive than gelatin. Based on failure patterns and brain tissue rate-sensitive characteristics, Sylgard was found to be an appropriate simulant. Compared with spherical projectile data, full-metal jacket (FMJ) projectiles produced different temporary cavity and pressures, demonstrating shape effects. Models using Sylgard gel and FMJ projectiles are appropriate to enhance understanding and mechanisms of ballistic brain injury.

  4. Open Knee: Open Source Modeling and Simulation in Knee Biomechanics.

    Science.gov (United States)

    Erdemir, Ahmet

    2016-02-01

    Virtual representations of the knee joint can provide clinicians, scientists, and engineers the tools to explore mechanical functions of the knee and its tissue structures in health and disease. Modeling and simulation approaches such as finite element analysis also provide the possibility to understand the influence of surgical procedures and implants on joint stresses and tissue deformations. A large number of knee joint models are described in the biomechanics literature. However, freely accessible, customizable, and easy-to-use models are scarce. Availability of such models can accelerate clinical translation of simulations, where labor-intensive reproduction of model development steps can be avoided. Interested parties can immediately utilize readily available models for scientific discovery and clinical care. Motivated by this gap, this study aims to describe an open source and freely available finite element representation of the tibiofemoral joint, namely Open Knee, which includes the detailed anatomical representation of the joint's major tissue structures and their nonlinear mechanical properties and interactions. Three use cases illustrate customization potential of the model, its predictive capacity, and its scientific and clinical utility: prediction of joint movements during passive flexion, examining the role of meniscectomy on contact mechanics and joint movements, and understanding anterior cruciate ligament mechanics. A summary of scientific and clinically directed studies conducted by other investigators are also provided. The utilization of this open source model by groups other than its developers emphasizes the premise of model sharing as an accelerator of simulation-based medicine. Finally, the imminent need to develop next-generation knee models is noted. These are anticipated to incorporate individualized anatomy and tissue properties supported by specimen-specific joint mechanics data for evaluation, all acquired in vitro from varying age

  5. Yellow Tongue

    Science.gov (United States)

    ... may suggest jaundice References Goldstein BG, et al. Oral lesions. http://uptodate.com/home. Accessed Jan. 21, 2015. ... Jan. 27, 2015. Geographic tongue. American Academy of Oral and Maxillofacial Pathology. http://www.aaomp.org/public/geographic-tongue.php. ...

  6. Tongue (image)

    Science.gov (United States)

    The tongue is mainly composed of muscles. It is covered with a mucous membrane. Small nodules of tissue (papillae) cover the upper surface of the tongue. Between the papillae are the taste buds, which ...

  7. A biomechanical model for fluidization of cells under dynamic strain.

    Science.gov (United States)

    Wu, Tenghu; Feng, James J

    2015-01-06

    Recent experiments have investigated the response of smooth muscle cells to transient stretch-compress (SC) and compress-stretch (CS) maneuvers. The results indicate that the transient SC maneuver causes a sudden fluidization of the cell while the CS maneuver does not. To understand this asymmetric behavior, we have built a biomechanical model to probe the response of stress fibers to the two maneuvers. The model couples the cross-bridge cycle of myosin motors with a viscoelastic Kelvin-Voigt element that represents the stress fiber. Simulation results point to the sensitivity of the myosin detachment rate to tension as the cause for the asymmetric response of the stress fiber to the CS and SC maneuvers. For the SC maneuver, the initial stretch increases the tension in the stress fiber and suppresses myosin detachment. The subsequent compression then causes a large proportion of the myosin population to disengage rapidly from actin filaments. This leads to the disassembly of the stress fibers and the observed fluidization. In contrast, the CS maneuver only produces a mild loss of myosin motors and no fluidization.

  8. A fundamental model of quasi-static wheelchair biomechanics.

    Science.gov (United States)

    Leary, M; Gruijters, J; Mazur, M; Subic, A; Burton, M; Fuss, F K

    2012-11-01

    The performance of a wheelchair system is a function of user anatomy, including arm segment lengths and muscle parameters, and wheelchair geometry, in particular, seat position relative to the wheel hub. To quantify performance, researchers have proposed a number of predictive models. In particular, the model proposed by Richter is extremely useful for providing initial analysis as it is simple to apply and provides insight into the peak and transient joint torques required to achieve a given angular velocity. The work presented in this paper identifies and corrects a critical error; specifically that the Richter model incorrectly predicts that shoulder torque is due to an anteflexing muscle moment. This identified error was confirmed analytically, graphically and numerically. The authors have developed a corrected, fundamental model which identifies that the shoulder anteflexes only in the first half of the push phase and retroflexes in the second half. The fundamental model has been extended by the authors to obtain novel data on joint and net power as a function of push progress. These outcomes indicate that shoulder power is positive in the first half of the push phase (concentrically contracting anteflexors) and negative in the second half (eccentrically contracting retroflexors). As the eccentric contraction introduces adverse negative power, these considerations are essential when optimising wheelchair design in terms of the user's musculoskeletal system. The proposed fundamental model was applied to assess the effect of vertical seat position on joint torques and power. Increasing the seat height increases the peak positive (concentric) shoulder and elbow torques while reducing the associated (eccentric) peak negative torque. Furthermore, the transition from positive to negative shoulder torque (as well as from positive to negative power) occurs later in the push phase with increasing seat height. These outcomes will aid in the optimisation of manual

  9. Tongue Disorders

    Science.gov (United States)

    Your tongue helps you taste, swallow, and chew. You also use it to speak. Your tongue is made up of many muscles. The upper surface contains your taste buds. Problems with the tongue include Pain Swelling Changes in color or texture ...

  10. Future of crash dummies and biomechanical mathematical models

    NARCIS (Netherlands)

    Wismans, J.S.H.M.

    2000-01-01

    Thorough knowledge of the characteristics of the human body and its behaviour under extreme loading conditions is essential in order to prevent the serious consequences of road and other accidents. This field of research is called injury or impact biomechanics. In order to study the human body respo

  11. Patient-specific biomechanical model as whole-body CT image registration tool.

    Science.gov (United States)

    Li, Mao; Miller, Karol; Joldes, Grand Roman; Doyle, Barry; Garlapati, Revanth Reddy; Kikinis, Ron; Wittek, Adam

    2015-05-01

    Whole-body computed tomography (CT) image registration is important for cancer diagnosis, therapy planning and treatment. Such registration requires accounting for large differences between source and target images caused by deformations of soft organs/tissues and articulated motion of skeletal structures. The registration algorithms relying solely on image processing methods exhibit deficiencies in accounting for such deformations and motion. We propose to predict the deformations and movements of body organs/tissues and skeletal structures for whole-body CT image registration using patient-specific non-linear biomechanical modelling. Unlike the conventional biomechanical modelling, our approach for building the biomechanical models does not require time-consuming segmentation of CT scans to divide the whole body into non-overlapping constituents with different material properties. Instead, a Fuzzy C-Means (FCM) algorithm is used for tissue classification to assign the constitutive properties automatically at integration points of the computation grid. We use only very simple segmentation of the spine when determining vertebrae displacements to define loading for biomechanical models. We demonstrate the feasibility and accuracy of our approach on CT images of seven patients suffering from cancer and aortic disease. The results confirm that accurate whole-body CT image registration can be achieved using a patient-specific non-linear biomechanical model constructed without time-consuming segmentation of the whole-body images.

  12. Modelling the learning of biomechanics and visual planning for decision-making of motor actions.

    Science.gov (United States)

    Cos, Ignasi; Khamassi, Mehdi; Girard, Benoît

    2013-11-01

    Recent experiments showed that the bio-mechanical ease and end-point stability associated to reaching movements are predicted prior to movement onset, and that these factors exert a significant influence on the choice of movement. As an extension of these results, here we investigate whether the knowledge about biomechanical costs and their influence on decision-making are the result of an adaptation process taking place during each experimental session or whether this knowledge was learned at an earlier stage of development. Specifically, we analysed both the pattern of decision-making and its fluctuations during each session, of several human subjects making free choices between two reaching movements that varied in path distance (target relative distance), biomechanical cost, aiming accuracy and stopping requirement. Our main result shows that the effect of biomechanics is well established at the start of the session, and that, consequently, the learning of biomechanical costs in decision-making occurred at an earlier stage of development. As a means to characterise the dynamics of this learning process, we also developed a model-based reinforcement learning model, which generates a possible account of how biomechanics may be incorporated into the motor plan to select between reaching movements. Results obtained in simulation showed that, after some pre-training corresponding to a motor babbling phase, the model can reproduce the subjects' overall movement preferences. Although preliminary, this supports that the knowledge about biomechanical costs may have been learned in this manner, and supports the hypothesis that the fluctuations observed in the subjects' behaviour may adapt in a similar fashion.

  13. Modeling of the condyle elements within a biomechanical knee model

    DEFF Research Database (Denmark)

    Ribeiro, Ana; Rasmussen, John; Flores, Paulo

    2012-01-01

    The development of a computational multibody knee model able to capture some of the fundamental properties of the human knee articulation is presented. This desideratum is reached by including the kinetics of the real knee articulation. The research question is whether an accurate modeling of the...

  14. Soft Tissue Structure Modelling for Use in Orthopaedic Applications and Musculoskeletal Biomechanics

    Directory of Open Access Journals (Sweden)

    E. A. Audenaert

    2010-01-01

    Full Text Available We present our methodology for the three-dimensional anatomical and geometrical description of soft tissues, relevant for orthopaedic surgical applications and musculoskeletal biomechanics. The technique involves the segmentation and geometrical description of muscles and neurovascular structures from high-resolution computer tomography scanning for the reconstruction of generic anatomical models. These models can be used for quantitative interpretation of anatomical and biomechanical aspects of different soft tissue structures. This approach should allow the use of these data in other application fields, such as musculoskeletal modelling, simulations for radiation therapy, and databases for use in minimally invasive, navigated and robotic surgery.

  15. Fluid–Structure Interaction-Based Biomechanical Perception Model for Tactile Sensing

    Science.gov (United States)

    Wang, Zheng

    2013-01-01

    The reproduced tactile sensation of haptic interfaces usually selectively reproduces a certain object attribute, such as the object's material reflected by vibration and its surface shape by a pneumatic nozzle array. Tactile biomechanics investigates the relation between responses to an external load stimulus and tactile perception and guides the design of haptic interface devices via a tactile mechanism. Focusing on the pneumatic haptic interface, we established a fluid–structure interaction-based biomechanical model of responses to static and dynamic loads and conducted numerical simulation and experiments. This model provides a theoretical basis for designing haptic interfaces and reproducing tactile textures. PMID:24260228

  16. Fluid-structure interaction-based biomechanical perception model for tactile sensing.

    Science.gov (United States)

    Wang, Zheng

    2013-01-01

    The reproduced tactile sensation of haptic interfaces usually selectively reproduces a certain object attribute, such as the object's material reflected by vibration and its surface shape by a pneumatic nozzle array. Tactile biomechanics investigates the relation between responses to an external load stimulus and tactile perception and guides the design of haptic interface devices via a tactile mechanism. Focusing on the pneumatic haptic interface, we established a fluid-structure interaction-based biomechanical model of responses to static and dynamic loads and conducted numerical simulation and experiments. This model provides a theoretical basis for designing haptic interfaces and reproducing tactile textures.

  17. A survey on stochastic multi-scale modeling in biomechanics: computational challenges

    CERN Document Server

    Favino, Marco; Pivkin, Igor

    2016-01-01

    During the last decade, multi-scale models in mechanics, bio-mechanics and life sciences have gained increasing attention. Using multi-scale approaches, effects on different time and length scales, such as, e.g., cellular and organ scale, can be coupled and their interaction can be studied. Clearly, this requires the development of new mathematical models and numerical methods for multi-scale problems, in order to provide reliable and efficient tools for the investigation of multi-scale effects. Here, we give an overview on existing numerical approaches for multi-scale simulations in bio-mechanics with particular emphasis on stochastic effects.

  18. Fluid-structure interaction-based biomechanical perception model for tactile sensing.

    Directory of Open Access Journals (Sweden)

    Zheng Wang

    Full Text Available The reproduced tactile sensation of haptic interfaces usually selectively reproduces a certain object attribute, such as the object's material reflected by vibration and its surface shape by a pneumatic nozzle array. Tactile biomechanics investigates the relation between responses to an external load stimulus and tactile perception and guides the design of haptic interface devices via a tactile mechanism. Focusing on the pneumatic haptic interface, we established a fluid-structure interaction-based biomechanical model of responses to static and dynamic loads and conducted numerical simulation and experiments. This model provides a theoretical basis for designing haptic interfaces and reproducing tactile textures.

  19. Pilot biomechanical design of biomaterials for artificial nucleus prosthesis using 3D finite-element modeling

    Institute of Scientific and Technical Information of China (English)

    Qijin Huang; Guoquan Liu; Yong Li; Jin Gao; Zhengqiu Gu; Yuanzheng Ma; Haibin Xue

    2004-01-01

    Pilot biomechanical design of biomaterials for artificial nucleus prosthesis was carried out based on the 3D finite-element method. Two 3D models of lumbar intervertebral disc respectively with a real human nucleus and with the nucleus removed were developed and validated using published experimental and clinical data. Then the models with a stainless steel nucleus prosthesis implanted and with polymer nucleus prostheses of various properties implanted were used for the 3D finite-element biomechanical analysis. All the above simulation and analysis were carried out for the L4/L5 disc under a human worst-daily compression load of 2000 N. The results show that the polymer materials with Young's modulus of elasticity E = 0.1-100 MPa and Poisson's ratio v=0.35-0.5 are suitable to produce artificial nucleus prosthesis in view of biomechanical consideration.

  20. Biomechanical Strain Exacerbates Inflammation on a Progeria-on-a-Chip Model

    NARCIS (Netherlands)

    Ribas, J.; Zhang, Y.S.; Pitrez, P.R.; Leijten, J.C.H.; Miscuglio, M.; Rouwkema, J.; Dokmeci, M.R.; Nissan, X.; Ferreira, L.; Khademhosseini, A.

    2017-01-01

    A progeria-on-a-chip model is engineered to recapitulate the biomechanical dynamics of vascular disease and aging. The model shows an exacerbated injury response to strain and is rescued by pharmacological treatments. The progeria-on-a-chip is expected to drive the discovery of new drugs and to eluc

  1. Biomechanical comparison of the human cadaveric pelvis with a fourth generation composite model.

    Science.gov (United States)

    Girardi, Brandon L; Attia, Tarik; Backstein, David; Safir, Oleg; Willett, Thomas L; Kuzyk, Paul R T

    2016-02-29

    The use of cadavers for orthopaedic biomechanics research is well established, but presents difficulties to researchers in terms of cost, biosafety, availability, and ease of use. High fidelity composite models of human bone have been developed for use in biomechanical studies. While several studies have utilized composite models of the human pelvis for testing orthopaedic reconstruction techniques, few biomechanical comparisons of the properties of cadaveric and composite pelves exist. The aim of this study was to compare the mechanical properties of cadaveric pelves to those of the 4th generation composite model. An Instron ElectroPuls E10000 mechanical testing machine was used to load specimens with orientation, boundary conditions and degrees of freedom that approximated those occurring during the single legged phase of walking, including hip abductor force. Each specimen was instrumented with strain gauge rosettes. Overall specimen stiffness and principal strains were calculated from the test data. Composite specimens showed significantly higher overall stiffness and slightly less overall variability between specimens (composite K=1448±54N/m, cadaver K=832±62N/m; p<0.0001). Strains measured at specific sites in the composite models and cadavers were similar (but did differ) only when the applied load was scaled to overall construct stiffness. This finding regarding strain distribution and the difference in overall stiffness must be accounted for when using these composite models for biomechanics research. Altering the cortical wall thickness or tuning the elastic moduli of the composite material may improve future generations of the composite model.

  2. Virtual fracture reduction of the acetabulum using a rigid body biomechanical model

    OpenAIRE

    Boudissa, Mehdi; Chabanas, Matthieu; Oliveri, Hadrien; Tonetti, Jérôme

    2014-01-01

    International audience; Acetabular fractures are a challenge in orthopaedic surgery. A simple rigid body biomechanical model of the hip is proposed to simulate the fracture reduction. The action of surgical tools can be simulated interactively, which enables clinicians to evaluate different strategies for a better surgical planning.

  3. Geographic Tongue

    Science.gov (United States)

    ... cases, most often related to eating hot, spicy, salty or acidic foods Many people with geographic tongue ... sensitive oral tissues, including: Hot, spicy, acidic or salty foods Tobacco products Toothpaste that contains tartar-control ...

  4. Tongue problems

    Science.gov (United States)

    ... Tongue pain may also occur with: Diabetic neuropathy Leukoplakia Mouth ulcers Oral cancer After menopause, some women ... problem. Medicine may be prescribed for mouth ulcers, leukoplakia, oral cancer, and other mouth sores. Anti-inflammatory ...

  5. Geographic tongue

    Science.gov (United States)

    ... for a long time. When to Contact a Medical Professional Call your health care provider if the symptoms last longer than 10 days. Seek immediate medical help if: You have breathing problems. Your tongue ...

  6. Are cranial biomechanical simulation data linked to known diets in extant taxa? A method for applying diet-biomechanics linkage models to infer feeding capability of extinct species.

    Science.gov (United States)

    Tseng, Zhijie Jack; Flynn, John J

    2015-01-01

    Performance of the masticatory system directly influences feeding and survival, so adaptive hypotheses often are proposed to explain craniodental evolution via functional morphology changes. However, the prevalence of "many-to-one" association of cranial forms and functions in vertebrates suggests a complex interplay of ecological and evolutionary histories, resulting in redundant morphology-diet linkages. Here we examine the link between cranial biomechanical properties for taxa with different dietary preferences in crown clade Carnivora, the most diverse clade of carnivorous mammals. We test whether hypercarnivores and generalists can be distinguished based on cranial mechanical simulation models, and how such diet-biomechanics linkages relate to morphology. Comparative finite element and geometric morphometrics analyses document that predicted bite force is positively allometric relative to skull strain energy; this is achieved in part by increased stiffness in larger skull models and shape changes that resist deformation and displacement. Size-standardized strain energy levels do not reflect feeding preferences; instead, caniform models have higher strain energy than feliform models. This caniform-feliform split is reinforced by a sensitivity analysis using published models for six additional taxa. Nevertheless, combined bite force-strain energy curves distinguish hypercarnivorous versus generalist feeders. These findings indicate that the link between cranial biomechanical properties and carnivoran feeding preference can be clearly defined and characterized, despite phylogenetic and allometric effects. Application of this diet-biomechanics linkage model to an analysis of an extinct stem carnivoramorphan and an outgroup creodont species provides biomechanical evidence for the evolution of taxa into distinct hypercarnivorous and generalist feeding styles prior to the appearance of crown carnivoran clades with similar feeding preferences.

  7. Are cranial biomechanical simulation data linked to known diets in extant taxa? A method for applying diet-biomechanics linkage models to infer feeding capability of extinct species.

    Directory of Open Access Journals (Sweden)

    Zhijie Jack Tseng

    Full Text Available Performance of the masticatory system directly influences feeding and survival, so adaptive hypotheses often are proposed to explain craniodental evolution via functional morphology changes. However, the prevalence of "many-to-one" association of cranial forms and functions in vertebrates suggests a complex interplay of ecological and evolutionary histories, resulting in redundant morphology-diet linkages. Here we examine the link between cranial biomechanical properties for taxa with different dietary preferences in crown clade Carnivora, the most diverse clade of carnivorous mammals. We test whether hypercarnivores and generalists can be distinguished based on cranial mechanical simulation models, and how such diet-biomechanics linkages relate to morphology. Comparative finite element and geometric morphometrics analyses document that predicted bite force is positively allometric relative to skull strain energy; this is achieved in part by increased stiffness in larger skull models and shape changes that resist deformation and displacement. Size-standardized strain energy levels do not reflect feeding preferences; instead, caniform models have higher strain energy than feliform models. This caniform-feliform split is reinforced by a sensitivity analysis using published models for six additional taxa. Nevertheless, combined bite force-strain energy curves distinguish hypercarnivorous versus generalist feeders. These findings indicate that the link between cranial biomechanical properties and carnivoran feeding preference can be clearly defined and characterized, despite phylogenetic and allometric effects. Application of this diet-biomechanics linkage model to an analysis of an extinct stem carnivoramorphan and an outgroup creodont species provides biomechanical evidence for the evolution of taxa into distinct hypercarnivorous and generalist feeding styles prior to the appearance of crown carnivoran clades with similar feeding preferences.

  8. First Reported Cases of Biomechanically Adaptive Bone Modeling in Non-Avian Dinosaurs.

    Directory of Open Access Journals (Sweden)

    Jorge Cubo

    Full Text Available Predator confrontation or predator evasion frequently produces bone fractures in potential prey in the wild. Although there are reports of healed bone injuries and pathologies in non-avian dinosaurs, no previously published instances of biomechanically adaptive bone modeling exist. Two tibiae from an ontogenetic sample of fifty specimens of the herbivorous dinosaur Maiasaura peeblesorum (Ornithopoda: Hadrosaurinae exhibit exostoses. We show that these outgrowths are cases of biomechanically adaptive periosteal bone modeling resulting from overstrain on the tibia after a fibula fracture. Histological and biomechanical results are congruent with predictions derived from this hypothesis. Histologically, the outgrowths are constituted by radial fibrolamellar periosteal bone tissue formed at very high growth rates, as expected in a process of rapid strain equilibration response. These outgrowths show greater compactness at the periphery, where tensile and compressive biomechanical constraints are higher. Moreover, these outgrowths increase the maximum bending strength in the direction of the stresses derived from locomotion. They are located on the antero-lateral side of the tibia, as expected in a presumably bipedal one year old individual, and in the posterior position of the tibia, as expected in a presumably quadrupedal individual at least four years of age. These results reinforce myological evidence suggesting that Maiasaura underwent an ontogenetic shift from the primitive ornithischian bipedal condition when young to a derived quadrupedal posture when older.

  9. First Reported Cases of Biomechanically Adaptive Bone Modeling in Non-Avian Dinosaurs.

    Science.gov (United States)

    Cubo, Jorge; Woodward, Holly; Wolff, Ewan; Horner, John R

    2015-01-01

    Predator confrontation or predator evasion frequently produces bone fractures in potential prey in the wild. Although there are reports of healed bone injuries and pathologies in non-avian dinosaurs, no previously published instances of biomechanically adaptive bone modeling exist. Two tibiae from an ontogenetic sample of fifty specimens of the herbivorous dinosaur Maiasaura peeblesorum (Ornithopoda: Hadrosaurinae) exhibit exostoses. We show that these outgrowths are cases of biomechanically adaptive periosteal bone modeling resulting from overstrain on the tibia after a fibula fracture. Histological and biomechanical results are congruent with predictions derived from this hypothesis. Histologically, the outgrowths are constituted by radial fibrolamellar periosteal bone tissue formed at very high growth rates, as expected in a process of rapid strain equilibration response. These outgrowths show greater compactness at the periphery, where tensile and compressive biomechanical constraints are higher. Moreover, these outgrowths increase the maximum bending strength in the direction of the stresses derived from locomotion. They are located on the antero-lateral side of the tibia, as expected in a presumably bipedal one year old individual, and in the posterior position of the tibia, as expected in a presumably quadrupedal individual at least four years of age. These results reinforce myological evidence suggesting that Maiasaura underwent an ontogenetic shift from the primitive ornithischian bipedal condition when young to a derived quadrupedal posture when older.

  10. Mathematical functions and their properties as relevant to the biomechanical modeling of cell and tissue damage.

    Science.gov (United States)

    Gefen, Amit

    2010-02-01

    The extrapolation of biological damage from a biomechanical model requires that a closed-form mathematical damage threshold function (DTF) be included in the model. A DTF typically includes a generic load variable, being the critical load (e.g., pressure, strain, temperature) causing irreversible tissue or cell damage, and a generic time variable, which represents the exposure to the load (e.g., duration, strain rate). Despite the central role that DTFs play in biomechanical studies, there is no coherent literature on how to formulate a DTF, excluding the field of heat-induced damage studies. This technical note describes six mathematical function types (Richards, Boltzmann, Morgan-Mercer-Flodin, Gompertz, Weibull, Bertalanffy) that are suitable for formulating a wide range of DTFs. These functions were adapted from the theory of restricted growth, and were fitted herein to describe biomechanical damage phenomena. Relevant properties of each adapted function type were extracted to allow efficient fitting of its parameters to empirical biomechanical data, and some practical examples are provided.

  11. First Reported Cases of Biomechanically Adaptive Bone Modeling in Non-Avian Dinosaurs

    Science.gov (United States)

    Cubo, Jorge; Woodward, Holly; Wolff, Ewan; Horner, John R.

    2015-01-01

    Predator confrontation or predator evasion frequently produces bone fractures in potential prey in the wild. Although there are reports of healed bone injuries and pathologies in non-avian dinosaurs, no previously published instances of biomechanically adaptive bone modeling exist. Two tibiae from an ontogenetic sample of fifty specimens of the herbivorous dinosaur Maiasaura peeblesorum (Ornithopoda: Hadrosaurinae) exhibit exostoses. We show that these outgrowths are cases of biomechanically adaptive periosteal bone modeling resulting from overstrain on the tibia after a fibula fracture. Histological and biomechanical results are congruent with predictions derived from this hypothesis. Histologically, the outgrowths are constituted by radial fibrolamellar periosteal bone tissue formed at very high growth rates, as expected in a process of rapid strain equilibration response. These outgrowths show greater compactness at the periphery, where tensile and compressive biomechanical constraints are higher. Moreover, these outgrowths increase the maximum bending strength in the direction of the stresses derived from locomotion. They are located on the antero-lateral side of the tibia, as expected in a presumably bipedal one year old individual, and in the posterior position of the tibia, as expected in a presumably quadrupedal individual at least four years of age. These results reinforce myological evidence suggesting that Maiasaura underwent an ontogenetic shift from the primitive ornithischian bipedal condition when young to a derived quadrupedal posture when older. PMID:26153689

  12. Embryonic tongue morphogenesis in an organ culture model of mouse mandibular arches: blocking Sonic hedgehog signaling leads to microglossia.

    Science.gov (United States)

    Torii, Daisuke; Soeno, Yuuichi; Fujita, Kazuya; Sato, Kaori; Aoba, Takaaki; Taya, Yuji

    2016-01-01

    Mouse tongue development is initiated with the formation of lateral lingual swellings just before fusion between the mediodorsal surfaces of the mandibular arches at around embryonic day 11.0. Here, we investigated the role of Sonic hedgehog (Shh) signaling in embryonic mouse tongue morphogenesis. For this, we used an organ culture model of the mandibular arches from mouse embryos at embryonic day 10.5. When the Shh signaling inhibitor jervine was added to the culture medium for 24-96 h, the formation of lateral lingual swellings and subsequent epithelial invagination into the mesenchyme were impaired markedly, leading to a hypoplastic tongue with an incomplete oral sulcus. Notably, jervine treatment reduced the proliferation of non-myogenic mesenchymal cells at the onset of forming the lateral lingual swellings, whereas it did not affect the proliferation and differentiation of a myogenic cell lineage, which created a cell community at the central circumferential region of the lateral lingual swellings as seen in vivo and in control cultures lacking the inhibitor. Thus, epithelium-derived Shh signaling stimulates the proliferation of non-myogenic mesenchymal cells essential for forming lateral lingual swellings and contributes to epithelial invagination into the mesenchyme during early tongue development.

  13. Stabilizing PID controllers for a single-link biomechanical model with position, velocity, and force feedback.

    Science.gov (United States)

    Iqbal, Kamran; Roy, Anindo

    2004-12-01

    In this paper we address the problem of PID stabilization of a single-link inverted pendulum-based biomechanical model with force feedback, two levels of position and velocity feedback, and with delays in all the feedback loops. The novelty of the proposed model lies in its physiological relevance, whereby both small and medium latency sensory feedbacks from muscle spindle (MS), and force feedback from Golgi tendon organ (GTO) are included in the formulation. The biomechanical model also includes active and passive viscoelastic feedback from Hill-type muscle model and a second-order low-pass function for muscle activation. The central nervous system (CNS) regulation of postural movement is represented by a proportional-integral-derivative (PID) controller. Padé approximation of delay terms is employed to arrive at an overall rational transfer function of the biomechanical model. The Hermite-Biehler theorem is then used to derive stability results, leading to the existence of stabilizing PID controllers. An algorithm for selection of stabilizing feedback gains is developed using the linear matrix inequality (LMI) approach.

  14. Anterolateral Versus Medial Plating of Distal Extra-articular Tibia Fractures: A Biomechanical Model.

    Science.gov (United States)

    Pirolo, Joseph M; Behn, Anthony W; Abrams, Geoffrey D; Bishop, Julius A

    2015-09-01

    Both medial and anterolateral plate applications have been described for the treatment of distal tibia fractures, each with distinct advantages and disadvantages. The objective of this study was to compare the biomechanical properties of medial and anterolateral plating constructs used to stabilize simulated varus and valgus fracture patterns of the distal tibia. In 16 synthetic tibia models, a 45° oblique cut was made to model an Orthopedic Trauma Association type 43-A1.2 distal tibia fracture in either a varus or valgus injury pattern. Each fracture was then reduced and plated with a precontoured medial or anterolateral distal tibia plate. The specimens were biomechanically tested in axial and torsional loading, cyclic axial loading, and load to failure. For the varus fracture pattern, medial plating showed less fracture site displacement and rotation and was stiffer in both axial and torsional loading (Ptibia fractures.

  15. Biomechanical Model for Evaluation of Pediatric Upper Extremity Joint Dynamics during Wheelchair Mobility

    OpenAIRE

    2013-01-01

    Pediatric manual wheelchair users (MWU) require high joint demands on their upper extremity (UE) during wheelchair mobility, leading them to be at risk of developing pain and pathology. Studies have examined UE biomechanics during wheelchair mobility in the adult population; however, current methods for evaluating UE joint dynamics of pediatric MWU are limited. An inverse dynamics model is proposed to characterize three-dimensional UE joint kinematics and kinetics during pediatric wheelchair ...

  16. Hill’s and Huxley’s muscle models - tools for simulations in biomechanics

    OpenAIRE

    Jovanović Kosta; Vranić Jovana; Miljković Nadica

    2015-01-01

    Numerous mathematical models of human skeletal muscles have been developed. However, none of them is adopted as a general one and each of them is suggested for some specific purpose. This topic is essential in humanoid robotics, since we firstly need to understand how human moves and acts in order to exploit human movement patterns in robotics and design human like actuators. Simulations in biomechanics are intensively used in research of locomotion, safe h...

  17. Finite Element-Derived Surrogate Models of Locked Plate Fracture Fixation Biomechanics.

    Science.gov (United States)

    Wee, Hwabok; Reid, J Spence; Chinchilli, Vernon M; Lewis, Gregory S

    2017-03-01

    Internal fixation of bone fractures using plates and screws involves many choices-implant type, material, sizes, and geometric configuration-made by the surgeon. These decisions can be important for providing adequate stability to promote healing and prevent implant mechanical failure. The purpose of this study was to develop mathematical models of the relationships between fracture fixation construct parameters and resulting 3D biomechanics, based on parametric computer simulations. Finite element models of hundreds of different locked plate fixation constructs for midshaft diaphyseal fractures were systematically assembled using custom algorithms, and axial, torsional, and bending loadings were simulated. Multivariate regression was used to fit response surface polynomial equations relating fixation design parameters to outputs including maximum implant stresses, axial and shear strain at the fracture site, and construct stiffness. Surrogate models with as little as three regressors showed good fitting (R (2) = 0.62-0.97). Inner working length was the strongest predictor of maximum plate and screw stresses, and a variety of quadratic and interaction terms influenced resulting biomechanics. The framework presented in this study can be applied to additional types of bone fractures to provide clinicians and implant designers with clinical insight, surgical optimization, and a comprehensive mathematical description of biomechanics.

  18. Imaging of tongue carcinoma

    OpenAIRE

    Ong, Cheng K.; Chong, Vincent F.H.

    2006-01-01

    The tongue enables taste and plays a critical role in formation of food bolus and deglutition. The tongue is also crucial for speech and the earliest sign of tongue paresis is a change in the quality of speech. Given the importance of the tongue, tongue carcinoma should be accurately staged in order to optimise treatment options and preserve organ function. The intent of this review is to familiarise radiologists with the pertinent anatomy of the tongue and the behaviour of tongue carcinoma s...

  19. Ergonomic Models of Anthropometry, Human Biomechanics and Operator-Equipment Interfaces

    Science.gov (United States)

    Kroemer, Karl H. E. (Editor); Snook, Stover H. (Editor); Meadows, Susan K. (Editor); Deutsch, Stanley (Editor)

    1988-01-01

    The Committee on Human Factors was established in October 1980 by the Commission on Behavioral and Social Sciences and Education of the National Research Council. The committee is sponsored by the Office of Naval Research, the Air Force Office of Scientific Research, the Army Research Institute for the Behavioral and Social Sciences, the National Aeronautics and Space Administration, and the National Science Foundation. The workshop discussed the following: anthropometric models; biomechanical models; human-machine interface models; and research recommendations. A 17-page bibliography is included.

  20. Biomechanical evaluation of Caspar and Cervical Spine Locking Plate systems in a cadaveric model.

    Science.gov (United States)

    Clausen, J D; Ryken, T C; Traynelis, V C; Sawin, P D; Dexter, F; Goel, V K

    1996-06-01

    There exist two markedly different instrumentation systems for the anterior cervical spine: the Cervical Spine Locking Plate (CSLP) system, which uses unicortical screws with a locking hub mechanism for attachment, and the Caspar Trapezial Plate System, which is secured with unlocked bicortical screws. The biomechanical stability of these two systems was evaluated in a cadaveric model of complete C5-6 instability. The immediate stability was determined in six loading modalities: flexion, extension, right and left lateral bending, and right and left axial rotation. Biomechanical stability was reassessed following fatigue with 5000 cycles of flexion-extension, and finally, the spines were loaded in flexion until the instrumentation failed. The Caspar system stabilized significantly in flexion before (p < 0.05) but not after fatigue, and it stabilized significantly in extension before (p < 0.01) and after fatigue (p < 0.01). The CSLP system stabilized significantly in flexion before (p < 0.01) but not after fatigue, and it did not stabilize in extension before or after fatigue. The moment needed to produce failure in flexion did not differ substantially between the two plating systems. The discrepancy in the biomechanical stability of these two systems may be due to differences in bone screw fixation.

  1. Excessive Cold-tongue and Weak ENSO Asymmetry: Are These Two Common Biases in Climate Models Linked?

    Science.gov (United States)

    Sun, D. Z.

    2014-12-01

    Among the biases in the tropical Pacific that are common in the climate models, two stand out. One is the excessive cold-tongue in the mean state---the pool of the cold water that is normally in the eastern tropical Pacific extends too far to the west. The other is the underestimate of the asymmetry of El Nino-Southern Oscillation—the fact that El Nino and La Nina are more or less a mirror image of each other in the models while they are not so in the observations. Results from an analysis from CMIP5 models, forced ocean GCM experiments, as well as an analytical model are presented to suggest that these two common biases in our state-of-the-art models are linked. Specifically, an excessive cold-tongue in the mean climatological state makes the ENSO system more stable and thus leads to a more symmetric ENSO, while a more symmetric ENSO in turn results in less nonlinear heating from the ENSO events to the cental equatorial Pacific which in turn contributes to the development of an excessive cold-tongue. The finding underscores that errors in the mean state and ENSO tend to reinforce each other and thus explains why it has been difficult to simulate the tropical Pacific climate. Further comparison with observations suggests that these two biases are the symptoms of a single structural inadequacy in the models: a weak dynamical coupling between the atmosphere and ocean which puts the ENSO system in the models to a different dynamic regime than the obsereved. Measures that may help push the models closer to the observations are suggested.

  2. Biomechanical modeling and load-carrying simulation of lower limb exoskeleton.

    Science.gov (United States)

    Zhu, Yanhe; Zhang, Guoan; Zhang, Chao; Liu, Gangfeng; Zhao, Jie

    2015-01-01

    This paper introduces novel modern equipment-a lower extremity exoskeleton, which can implement the mutual complement and the interaction between human intelligence and the robot's mechanical strength. In order to provide a reference for the exoskeleton structure and the drive unit, the human biomechanics were modeled and analyzed by LifeModeler and Adams software to derive each joint kinematic parameter. The control was designed to implement the zero-force interaction between human and exoskeleton. Furthermore, simulations were performed to verify the control and assist effect. In conclusion, the system scheme of lower extremity exoskeleton is demonstrated to be feasible.

  3. Digital Astronaut Project Biomechanical Models: Biomechanical Modeling of Squat, Single-Leg Squat and Heel Raise Exercises on the Hybrid Ultimate Lifting Kit (HULK)

    Science.gov (United States)

    Thompson, William K.; Gallo, Christopher A.; Crentsil, Lawton; Lewandowski, Beth E.; Humphreys, Brad T.; DeWitt, John K.; Fincke, Renita S.; Mulugeta, Lealem

    2015-01-01

    The NASA Digital Astronaut Project (DAP) implements well-vetted computational models to predict and assess spaceflight health and performance risks, and to enhance countermeasure development. The DAP Musculoskeletal Modeling effort is developing computational models to inform exercise countermeasure development and to predict physical performance capabilities after a length of time in space. For example, integrated exercise device-biomechanical models can determine localized loading, which will be used as input to muscle and bone adaptation models to estimate the effectiveness of the exercise countermeasure. In addition, simulations of mission tasks can be used to estimate the astronaut's ability to perform the task after exposure to microgravity and after using various exercise countermeasures. The software package OpenSim (Stanford University, Palo Alto, CA) (Ref. 1) is being used to create the DAP biomechanical models and its built-in muscle model is the starting point for the DAP muscle model. During Exploration missions, such as those to asteroids and Mars, astronauts will be exposed to reduced gravity for extended periods. Therefore, the crew must have access to exercise countermeasures that can maintain their musculoskeletal and aerobic health. Exploration vehicles may have very limited volume and power available to accommodate such capabilities, even more so than the International Space Station (ISS). The exercise devices flown on Exploration missions must be designed to provide sufficient load during the performance of various resistance and aerobic/anaerobic exercises while meeting potential additional requirements of limited mass, volume and power. Given that it is not practical to manufacture and test (ground, analog and/or flight) all candidate devices, nor is it always possible to obtain data such as localized muscle and bone loading empirically, computational modeling can estimate the localized loading during various exercise modalities performed on

  4. Tongue-Tie (Ankyloglossia)

    Science.gov (United States)

    ... ENTCareers Marketplace Find an ENT Doctor Near You Tongue-tie (Ankyloglossia) Tongue-tie (Ankyloglossia) Patient Health Information ... may be serious in some individuals. When Is Tongue-tie a Problem That Needs Treatment? In Infants ...

  5. Biomechanical Stability of Juvidur and Bone Models on Osteosyntesic Materials

    Science.gov (United States)

    Grubor, Predrag; Mitković, Milorad; Grubor, Milan; Mitković, Milan; Meccariello, Luigi; Falzarano, Gabriele

    2016-01-01

    Introduction: Artificial models can be useful at approximate and qualitative research, which should give the preliminary results. Artificial models are usually made of photo-elastic plastic e.g.. juvidur, araldite in the three-dimensional contour shape of the bone. Anatomical preparations consist of the same heterogeneous, structural materials with extremely anisotropic and unequal highly elastic characteristics, which are embedded in a complex organic structure. The aim of the study: Examine the budget voltage and deformation of: dynamic compression plate (DCP), locking compression plate (LCP), Mitkovic internal fixator (MIF), Locked intramedullary nailing (LIN) on the compressive and bending forces on juvidur and veal bone models and compared the results of these two methods (juvidur, veal bone). Material and Methods: For the experimental study were used geometrically identical, anatomically shaped models of Juvidur and veal bones diameter of 30 mm and a length of 100 mm. Static tests were performed with SHIMADZU AGS-X testing machine, where the force of pressure (compression) increased from 0 N to 500 N, and then conducted relief. Bending forces grew from 0 N to 250 N, after which came into sharp relief. Results: On models of juvidur and veal bones studies have confirmed that uniform stability at the site of the fracture MIF with a coefficient ranking KMIF=0,1971, KLIN=0,2704, KDCP=0,2727 i KLCP=0,5821. Conclusion: On models of juvidur and veal bones working with Shimadzu AGS-X testing machine is best demonstrated MIF with a coefficient of 0.1971. PMID:27708489

  6. Models in injury biomechanics for improved passive vehicle safety

    NARCIS (Netherlands)

    Wismans, J.S.H.M.

    1996-01-01

    Thorough knowledge of the characteristics of the human body and its behaviour under extreme loading conditions is essential in order to prevent the serious consequences of road and other accidents. In order to study the human body response five type of models for the human body can be distinguished:

  7. Biomechanical modeling of eye trauma for different orbit anthropometries.

    Science.gov (United States)

    Weaver, Ashley A; Loftis, Kathryn L; Duma, Stefan M; Stitzel, Joel D

    2011-04-29

    In military, automotive, and sporting safety, there is concern over eye protection and the effects of facial anthropometry differences on risk of eye injury. The objective of this study is to investigate differences in orbital geometry and analyze their effect on eye impact injury. Clinical measurements of the orbital aperture, brow protrusion angle, eye protrusion, and the eye location within the orbit were used to develop a matrix of simulations. A finite element (FE) model of the orbit was developed from a computed tomography (CT) scan of an average male and transformed to model 27 different anthropometries. Impacts were modeled using an eye model incorporating lagrangian-eulerian fluid flow for the eye, representing a full eye for evaluation of omnidirectional impact and interaction with the orbit. Computational simulations of a Little League (CD25) baseball impact at 30.1m/s were conducted to assess the effect of orbit anthropometry on eye injury metrics. Parameters measured include stress and strain in the corneoscleral shell, internal dynamic eye pressure, and contact forces between the orbit, eye, and baseball. The location of peak stresses and strains was also assessed. Main effects and interaction effects identified in the statistical analysis illustrate the complex relationship between the anthropometric variation and eye response. The results of the study showed that the eye is more protected from impact with smaller orbital apertures, more brow protrusion, and less eye protrusion, provided that the orbital aperture is large enough to deter contact of the eye with the orbit.

  8. An integrated biomechanical modeling approach to the ergonomic evaluation of drywall installation.

    Science.gov (United States)

    Yuan, Lu; Buchholz, Bryan; Punnett, Laura; Kriebel, David

    2016-03-01

    Three different methodologies: work sampling, computer simulation and biomechanical modeling, were integrated to study the physical demands of drywall installation. PATH (Posture, Activity, Tools, and Handling), a work-sampling based method, was used to quantify the percent of time that the drywall installers were conducting different activities with different body segment (trunk, arm, and leg) postures. Utilizing Monte-Carlo simulation to convert the categorical PATH data into continuous variables as inputs for the biomechanical models, the required muscle contraction forces and joint reaction forces at the low back (L4/L5) and shoulder (glenohumeral and sternoclavicular joints) were estimated for a typical eight-hour workday. To demonstrate the robustness of this modeling approach, a sensitivity analysis was conducted to examine the impact of some quantitative assumptions that have been made to facilitate the modeling approach. The results indicated that the modeling approach seemed to be the most sensitive to both the distribution of work cycles for a typical eight-hour workday and the distribution and values of Euler angles that are used to determine the "shoulder rhythm." Other assumptions including the distribution of trunk postures did not appear to have a significant impact on the model outputs. It was concluded that the integrated approach might provide an applicable examination of physical loads during the non-routine construction work, especially for those operations/tasks that have certain patterns/sequences for the workers to follow.

  9. Development of a Dynamic Biomechanical Model for Load Carriage: Phase VI: Assessing Physiological and Biomechanical Loading Using the Portable Measurement System and the Dynamic Biomechanical Model

    Science.gov (United States)

    2007-12-01

    of the rucksack modeled are based on the current issue Clothe the Soldier (CTS) rucksack. This program has applications in quantifying the...estimés à partir des accélérations du haut du corps, ont été validés en les comparants aux angles d’inclinaison mesurés à l’aide d’un capteur à inertie et...During the first 3 seconds of each analysis, waist belt tension ramps up from 10 N to the final value of 60 N. This gradual application of tension

  10. Probabilistic Modeling Of Ocular Biomechanics In VIIP: Risk Stratification

    Science.gov (United States)

    Feola, A.; Myers, J. G.; Raykin, J.; Nelson, E. S.; Mulugeta, L.; Samuels, B.; Ethier, C. R.

    2016-01-01

    Visual Impairment and Intracranial Pressure (VIIP) syndrome is a major health concern for long-duration space missions. Currently, it is thought that a cephalad fluid shift in microgravity causes elevated intracranial pressure (ICP) that is transmitted along the optic nerve sheath (ONS). We hypothesize that this in turn leads to alteration and remodeling of connective tissue in the posterior eye which impacts vision. Finite element (FE) analysis is a powerful tool for examining the effects of mechanical loads in complex geometries. Our goal is to build a FE analysis framework to understand the response of the lamina cribrosa and optic nerve head to elevations in ICP in VIIP. To simulate the effects of different pressures on tissues in the posterior eye, we developed a geometric model of the posterior eye and optic nerve sheath and used a Latin hypercubepartial rank correlation coef-ficient (LHSPRCC) approach to assess the influence of uncertainty in our input parameters (i.e. pressures and material properties) on the peak strains within the retina, lamina cribrosa and optic nerve. The LHSPRCC approach was repeated for three relevant ICP ranges, corresponding to upright and supine posture on earth, and microgravity [1]. At each ICP condition we used intraocular pressure (IOP) and mean arterial pressure (MAP) measurements of in-flight astronauts provided by Lifetime Surveillance of Astronaut Health Program, NASA Johnson Space Center. The lamina cribrosa, optic nerve, retinal vessel and retina were modeled as linear-elastic materials, while other tissues were modeled as a Mooney-Rivlin solid (representing ground substance, stiffness parameter c1) with embedded collagen fibers (stiffness parameters c3, c4 and c5). Geometry creationmesh generation was done in Gmsh [2], while FEBio was used for all FE simulations [3]. The LHSPRCC approach resulted in correlation coefficients in the range of 1. To assess the relative influence of the uncertainty in an input parameter on

  11. Biomechanics of cells and tissues experiments, models and simulations

    CERN Document Server

    2013-01-01

    The application of methodological approaches and mathematical formalisms proper to Physics and Engineering to investigate and describe biological processes and design biological structures has led to the development of many disciplines in the context of computational biology and biotechnology. The best known applicative domain is tissue engineering and its branches. Recent domains of interest are in the field of biophysics, e.g.: multiscale mechanics of biological membranes and films and filaments; multiscale mechanics of adhesion; biomolecular motors and force generation.   Modern hypotheses, models, and tools are currently emerging and resulting from the convergence of the methods and philosophical approaches of the different research areas and disciplines. All these emerging approaches share the purpose of disentangling the complexity of organisms, tissues, and cells and mimicking the function of living systems. The contributions presented in this book are current research highlights of six challenging an...

  12. [Modelling metallic bars in an orthopaedic laboratory: postural and biomechanical analysis].

    Science.gov (United States)

    Draicchio, F; Miccio, A; Mari, S; Silvetti, A; Forzano, F; Ranavolo, A

    2012-01-01

    Aim of this work is to assess, with an objective technique (i.e. surface electromyography), the upper limb biomechanical load in workers specialized in manufacturing of orthopedic prostheses. We considered two different working configurations (workstation height at 105 and 110 cm) and three different materials to be modeled (aluminum, steel and titanium). Our results showed significant differences between aluminum/steel and titanium bars. As regards the working configurations, we found differences in the muscle activation patterns between the two heights, with an increased exertion of the shoulder muscles at 110 cm with respect to 105.

  13. Effect of mouth-rinse formulations on oral malodour processes in tongue-derived perfusion biofilm model.

    Science.gov (United States)

    Saad, S; Hewett, K; Greenman, J

    2012-03-01

    An in vitro matrix biofilm perfusion model of tongue-derived microcosms for studying volatile sulfur compound (VSC) biogenesis has been previously described. The model was modified in order to monitor H(2)S in situ by use of a specialized electrode assembly based on microbial fuel cell technology. This system was designed to give real-time measurements expressed as electrode power output, which were proportional to H(2)S levels, measured by other means. In addition to the model modifications, the aim of this study was to demonstrate the biofilm responses following single or multiple exposure to biocidal, biostatic or VSC-inhibiting active compounds used in products. Tongue-derived biofilms (n = 6 per experiment) were perfused with one-fifth strength BHI at 20 ml h(-1) pH 7.2 and pulsed with putative treatment agent, placebo and controls including Zn(2+) ions and chlorhexidine (CHX). Compared with their pre-treatment conditions, all biofilms responded to the treatments in terms of reductions in hydrogen sulfide generation (as detected by the biofilm-electrode response) and other microbial volatile organic compounds (VOCs) as detected using a selected ion flow tube mass spectrometry analyser. The microbiological analysis of the treated and control biofilms show that test products (formulations with active agents) all gave reduced cell populations compared to the control biofilm. An order of effects (magnitude and duration) suggests that both the test agent and CHX produced the strongest reductions, distinct from the responses obtained for the placebo and water controls, which were largely similar. It is concluded that the in vitro perfusion model may be used to replicate many of the activities and reactions believed to be occurring by the tongue biofilm microflora within a real mouth, including H(2)S and VOC biogenesis and their inhibition by exposure to active agents.

  14. Biomechanics of Growing Trees: Mathematical Model, Numerical Resolution and Perspectives

    Science.gov (United States)

    Fourcaud, Thierry; Guillon, Thomas; Dumont, Yves

    2011-09-01

    The growth of trees is characterized by the elongation and thickening of its axes. New cells are formed at the periphery of the existing body, the properties of the older inner material being unchanged. The calculation of the progressive deflection of a growing stem is not a classical problem in mechanics for three main reasons: 1- the hypothesis of mass conservation is not valid; 2- the new material added at the periphery of the existing and deformed structure does not participate retroactively to the total equilibrium and tends to "fix" the actual shape; 3- an initial reference configuration corresponding to the unloaded structure cannot be classically defined to formulate the equilibrium equations. This paper proposes a theoretical framework that allows bypassing these difficulties. Equations adapted from the beam theory and considering the strong dependencies between space and time are given. A numerical scheme based on the finite element method is proposed to solve these equations. The model opens new research perspectives both in mathematics and plant biology.

  15. Combined Ultrasound Imaging and Biomechanical Modeling to Estimate Triceps Brachii Musculotendon Changes in Stroke Survivors

    Directory of Open Access Journals (Sweden)

    Le Li

    2016-01-01

    Full Text Available The aim of this study was to investigate the changes of musculotendon parameters of triceps brachii in persons after stroke based on subject-specific biomechanical modeling technique combined with in vivo ultrasound measurement. Five chronic stroke survivors and five normal control subjects were recruited. B-mode ultrasound was applied to measure muscle pennation angle and the optimal length of three heads of triceps’ brachii at different joint angle positions in resting and isometric contraction. Measured ultrasound data were used to reduce the unknown parameters during the modeling optimization process. The results showed that pennation angles varied with joint angles, and the longhead TRI pennation from stroke group was smaller than the literature value. The maximum isometric muscle stress from persons after stroke was significantly smaller than that found in the unimpaired subjects. The prediction of joint torque fits well with the measured data from the control group, whereas the prediction error is larger in results from persons after stroke. In vivo parameters from ultrasound data could help to build a subject-specific biomechanical model of elbow extensor for both unimpaired and hemiplegic subjects, and then the results driven from the model could enhance the understanding of motor function changes for persons after stroke.

  16. Modeling Analysis of Biomechanical Changes of Middle Ear and Cochlea in Otitis Media

    Science.gov (United States)

    Gan, Rong Z.; Zhang, Xiangming; Guan, Xiying

    2011-11-01

    A comprehensive finite element (FE) model of the human ear including the ear canal, middle ear, and spiral cochlea was developed using histological sections of human temporal bone. The cochlea was modeled with three chambers separated by the basilar membrane and Reissner's membrane and filled with perilymphatic fluid. The viscoelastic material behavior was applied to middle ear soft tissues based on dynamic measurements of tissues in our lab. The model was validated using the experimental data obtained in human temporal bones and then used to simulate various stages of otitis media (OM) including the changes of morphology, mechanical properties, pressure, and fluid level in the middle ear. Function alterations of the middle ear and cochlea in OM were derived from the model and compared with the measurements from temporal bones. This study indicates that OM can be simulated in the FE model to predict the hearing loss induced by biomechanical changes of the middle ear and cochlea.

  17. Mathematical Modelling of Biomechanical Interactions between Backpack and Bearer during Load Carriage

    Directory of Open Access Journals (Sweden)

    Lei Ren

    2013-01-01

    Full Text Available This paper proposes a three-dimensional mathematical model of the biomechanical interactions between backpack and bearer during load carriage. The model considers both the coupled pack motions, which follow the torso, and also the longitudinal compliance and damping in the backpack suspension. The pack interaction forces and moments, acting on the bearer, are determined from kinematic relationships, equations of motion, and a dynamic pack suspension model. The parameters of the pack suspension model were identified from test data obtained using a load carriage test rig. Output from the load carriage mathematical model has been compared with measurement data during human gait and conclusions drawn with regard to the validity of the proposed approach.

  18. Biomechanical properties of bone in a mouse model of Rett syndrome.

    Science.gov (United States)

    Kamal, Bushra; Russell, David; Payne, Anthony; Constante, Diogo; Tanner, K Elizabeth; Isaksson, Hanna; Mathavan, Neashan; Cobb, Stuart R

    2015-02-01

    Rett syndrome (RTT) is an X-linked genetic disorder and a major cause of intellectual disability in girls. Mutations in the methyl-CpG binding protein 2 (MECP2) gene are the primary cause of the disorder. Despite the dominant neurological phenotypes, MECP2 is expressed ubiquitously throughout the body and a number of peripheral phenotypes such as scoliosis, reduced bone mineral density and skeletal fractures are also common and important clinical features of the disorder. In order to explore whether MeCP2 protein deficiency results in altered structural and functional properties of bone and to test the potential reversibility of any defects, we have conducted a series of histological, imaging and biomechanical tests of bone in a functional knockout mouse model of RTT. Both hemizygous Mecp2(stop/y) male mice in which Mecp2 is silenced in all cells and female Mecp2(stop/+) mice in which Mecp2 is silenced in ~50% of cells as a consequence of random X-chromosome inactivation, revealed significant reductions in cortical bone stiffness, microhardness and tensile modulus. Microstructural analysis also revealed alterations in both cortical and cancellous femoral bone between wild-type and MeCP2-deficient mice. Furthermore, unsilencing of Mecp2 in adult mice cre-mediated stop cassette deletion resulted in a restoration of biomechanical properties (stiffness, microhardness) towards wild-type levels. These results show that MeCP2-deficiency results in overt, but potentially reversible, alterations in the biomechanical integrity of bone and highlights the importance of targeting skeletal phenotypes in considering the development of pharmacological and gene-based therapies.

  19. Robot-musculoskeletal dynamic biomechanical model in robot-assisted diaphyseal fracture reduction.

    Science.gov (United States)

    Li, Changsheng; Wang, Tianmiao; Hu, Lei; Zhang, Lihai; Zhao, Yanpeng; Du, Hailong; Wang, Lifeng; Tang, Peifu

    2015-01-01

    A number of issues that exist in common fracture reduction surgeries can be mitigated by robot-assisted fracture reduction. However, the safety of patients and the performance of the robot, which are closely related to the muscle forces, are important indexes that restrict the development of robots. Though researchers have done a great deal of work on the biomechanics of the musculoskeletal system, the dynamics of the musculoskeletal system, particularly the aspects related to the function of the robot, is not well understood. For this reason, we represent the complex biological system by establishing a dynamic biomechanical model based on the Hill muscle model and the Kane method for the robot that we have developed and the musculoskeletal system. We analyzed the relationship between the motion and force of the bone fragments and the robot during a simulation of a robot-assisted fracture reduction. The influence of the muscle force on the robot system was predicted and managed. The simulation results provide a basis for a fracture reduction path plan that ensures patient safety and a useful reference for the mechanical design of the robot.

  20. Using sensitivity analysis to validate the predictions of a biomechanical model of bite forces.

    Science.gov (United States)

    Sellers, William Irvin; Crompton, Robin Huw

    2004-02-01

    Biomechanical modelling has become a very popular technique for investigating functional anatomy. Modern computer simulation packages make producing such models straightforward and it is tempting to take the results produced at face value. However the predictions of a simulation are only valid when both the model and the input parameters are accurate and little work has been done to verify this. In this paper a model of the human jaw is produced and a sensitivity analysis is performed to validate the results. The model is built using the ADAMS multibody dynamic simulation package incorporating the major occlusive muscles of mastication (temporalis, masseter, medial and lateral pterygoids) as well as a highly mobile temporomandibular joint. This model is used to predict the peak three-dimensional bite forces at each teeth location, joint reaction forces, and the contributions made by each individual muscle. The results for occlusive bite-force (1080N at M1) match those previously published suggesting the model is valid. The sensitivity analysis was performed by sampling the input parameters from likely ranges and running the simulation many times rather than using single, best estimate values. This analysis shows that the magnitudes of the peak retractive forces on the lower teeth were highly sensitive to the chosen origin (and hence fibre direction) of the temporalis and masseter muscles as well as the laxity of the TMJ. Peak protrusive force was also sensitive to the masseter origin. These result shows that the model is insufficiently complex to estimate these values reliably although the much lower sensitivity values obtained for the bite forces in the other directions and also for the joint reaction forces suggest that these predictions are sound. Without the sensitivity analysis it would not have been possible to identify these weaknesses which strongly supports the use of sensitivity analysis as a validation technique for biomechanical modelling.

  1. Biomechanical analysis and modeling of different vertebral growth patterns in adolescent idiopathic scoliosis and healthy subjects

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    Driscoll Mark

    2011-05-01

    Full Text Available Abstract Background The etiology of AIS remains unclear, thus various hypotheses concerning its pathomechanism have been proposed. To date, biomechanical modeling has not been used to thoroughly study the influence of the abnormal growth profile (i.e., the growth rate of the vertebral body during the growth period on the pathomechanism of curve progression in AIS. This study investigated the hypothesis that AIS progression is associated with the abnormal growth profiles of the anterior column of the spine. Methods A finite element model of the spinal column including growth dynamics was utilized. The initial geometric models were constructed from the bi-planar radiographs of a normal subject. Based on this model, five other geometric models were generated to emulate different coronal and sagittal curves. The detailed modeling integrated vertebral body growth plates and growth modulation spinal biomechanics. Ten years of spinal growth was simulated using AIS and normal growth profiles. Sequential measures of spinal alignments were compared. Results (1 Given the initial lateral deformity, the AIS growth profile induced a significant Cobb angle increase, which was roughly between three to five times larger compared to measures utilizing a normal growth profile. (2 Lateral deformities were absent in the models containing no initial coronal curvature. (3 The presence of a smaller kyphosis did not produce an increase lateral deformity on its own. (4 Significant reduction of the kyphosis was found in simulation results of AIS but not when using the growth profile of normal subjects. Conclusion Results from this analysis suggest that accelerated growth profiles may encourage supplementary scoliotic progression and, thus, may pose as a progressive risk factor.

  2. Quantification of Subjective Scaling of Friction Using a Fingertip Biomechanical Model

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    Mohammad Abdolvahab

    2012-01-01

    Full Text Available Subjective scaling of friction is important in many applications in haptic technology. A nonhomogeneous biomechanical finite element model of fingertip is proposed in order to predict neural response of sensitive mechanoreceptors to frictional stimuli (Slowly Adapting SAII receptors under the glabrous skin. In a guided psychophysical experiment, ten human subjects were asked to scale several standard surfaces based on the perception of their frictional properties. Contact forces deployed during the exploratory time of one of the participants were captured in order to estimate required parameters for the model of contact in the simulation procedure. Consequently, the strain energy density at the location of a selective mechanoreceptor in the finite element model as a measure of discharge rate of the neural unit was compared to the subject’s perceptual evaluation of the relevant stimuli. It was observed that the subject’s scores correlate with the discharge rate of the given receptor.

  3. Biomechanical model produced from light-activated dental composite resins: a holographic analysis

    Science.gov (United States)

    Pantelić, Dejan; Vasiljević, Darko; Blažić, Larisa; Savić-Šević, Svetlana; Murić, Branka; Nikolić, Marko

    2013-11-01

    Light-activated dental composites, commonly applied in dentistry, can be used as excellent material for producing biomechanical models. They can be cast in almost any shape in an appropriate silicone mold and quickly solidified by irradiation with light in the blue part of the spectrum. In that way, it is possible to obtain any number of nearly identical casts. The models can be used to study the behavior of arbitrary structure under mechanical loads. To test the technique, a simple mechanical model of the tooth with a mesio-occluso-distal cavity was manufactured. Composite resin restoration was placed inside the cavity and light cured. Real-time holographic interferometry was used to analyze the contraction of the composite resin and its effect on the surrounding material. The results obtained in the holographic experiment were in good agreement with those obtained using the finite element method.

  4. Modelling and Analysis on Biomechanical Dynamic Characteristics of Knee Flexion Movement under Squatting

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    Jianping Wang

    2014-01-01

    Full Text Available The model of three-dimensional (3D geometric knee was built, which included femoral-tibial, patellofemoral articulations and the bone and soft tissues. Dynamic finite element (FE model of knee was developed to simulate both the kinematics and the internal stresses during knee flexion. The biomechanical experimental system of knee was built to simulate knee squatting using cadaver knees. The flexion motion and dynamic contact characteristics of knee were analyzed, and verified by comparing with the data from in vitro experiment. The results showed that the established dynamic FE models of knee are capable of predicting kinematics and the contact stresses during flexion, and could be an efficient tool for the analysis of total knee replacement (TKR and knee prosthesis design.

  5. Biomechanical analyses of prosthetic mesh repair in a hiatal hernia model.

    Science.gov (United States)

    Alizai, Patrick Hamid; Schmid, Sofie; Otto, Jens; Klink, Christian Daniel; Roeth, Anjali; Nolting, Jochen; Neumann, Ulf Peter; Klinge, Uwe

    2014-10-01

    Recurrence rate of hiatal hernia can be reduced with prosthetic mesh repair; however, type and shape of the mesh are still a matter of controversy. The purpose of this study was to investigate the biomechanical properties of four conventional meshes: pure polypropylene mesh (PP-P), polypropylene/poliglecaprone mesh (PP-U), polyvinylidenefluoride/polypropylene mesh (PVDF-I), and pure polyvinylidenefluoride mesh (PVDF-S). Meshes were tested either in warp direction (parallel to production direction) or perpendicular to the warp direction. A Zwick testing machine was used to measure elasticity and effective porosity of the textile probes. Stretching of the meshes in warp direction required forces that were up to 85-fold higher than the same elongation in perpendicular direction. Stretch stress led to loss of effective porosity in most meshes, except for PVDF-S. Biomechanical impact of the mesh was additionally evaluated in a hiatal hernia model. The different meshes were used either as rectangular patches or as circular meshes. Circular meshes led to a significant reinforcement of the hiatus, largely unaffected by the orientation of the warp fibers. In contrast, rectangular meshes provided a significant reinforcement only when warp fibers ran perpendicular to the crura. Anisotropic elasticity of prosthetic meshes should therefore be considered in hiatal closure with rectangular patches.

  6. Chemical and biomechanical characterization of hyperhomocysteinemic bone disease in an animal model

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    Howell David S

    2003-02-01

    Full Text Available Abstract Background Classical homocystinuria is an autosomal recessive disorder caused by cystathionine β-synthase (CBS deficiency and characterized by distinctive alterations of bone growth and skeletal development. Skeletal changes include a reduction in bone density, making it a potentially attractive model for the study of idiopathic osteoporosis. Methods To investigate this aspect of hyperhomocysteinemia, we supplemented developing chicks (n = 8 with 0.6% dl-homocysteine (hCySH for the first 8 weeks of life in comparison to controls (n = 10, and studied biochemical, biomechanical and morphologic effects of this nutritional intervention. Results hCySH-fed animals grew faster and had longer tibiae at the end of the study. Plasma levels of hCySH, methionine, cystathionine, and inorganic sulfate were higher, but calcium, phosphate, and other indices of osteoblast metabolism were not different. Radiographs of the lower limbs showed generalized osteopenia and accelerated epiphyseal ossification with distinct metaphyseal and suprametaphyseal lucencies similar to those found in human homocystinurics. Although biomechanical testing of the tibiae, including maximal load to failure and bone stiffness, indicated stronger bone, strength was proportional to the increased length and cortical thickness in the hCySH-supplemented group. Bone ash weights and IR-spectroscopy of cortical bone showed no difference in mineral content, but there were higher Ca2+/PO43- and lower Ca2+/CO32- molar ratios than in controls. Mineral crystallization was unchanged. Conclusion In this chick model, hyperhomocysteinemia causes greater radial and longitudinal bone growth, despite normal indices of bone formation. Although there is also evidence for an abnormal matrix and altered bone composition, our finding of normal biomechanical bone strength, once corrected for altered morphometry, suggests that any increase in the risk of long bone fracture in human hyperhomocysteinemic

  7. Evaluation of Nitinol staples for the Lapidus arthrodesis in a reproducible biomechanical model

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    Nicholas Alexander Russell

    2015-12-01

    Full Text Available While the Lapidus procedure is a widely accepted technique for treatment of hallux valgus, the optimal fixation method to maintain joint stability remains controversial. The purpose of this study was to evaluate the biomechanical properties of new Shape Memory Alloy staples arranged in different configurations in a repeatable 1st Tarsometatarsal arthrodesis model. Ten sawbones models of the whole foot (n=5 per group were reconstructed using a single dorsal staple or two staples in a delta configuration. Each construct was mechanically tested in dorsal four-point bending, medial four-point bending, dorsal three-point bending and plantar cantilever bending with the staples activated at 37°C. The peak load, stiffness and plantar gapping were determined for each test. Pressure sensors were used to measure the contact force and area of the joint footprint in each group. There was a significant (p < 0.05 increase in peak load in the two staple constructs compared to the single staple constructs for all testing modalities. Stiffness also increased significantly in all tests except dorsal four-point bending. Pressure sensor readings showed a significantly higher contact force at time zero and contact area following loading in the two staple constructs (p < 0.05. Both groups completely recovered any plantar gapping following unloading and restored their initial contact footprint. The biomechanical integrity and repeatability of the models was demonstrated with no construct failures due to hardware or model breakdown. Shape memory alloy staples provide fixation with the ability to dynamically apply and maintain compression across a simulated arthrodesis following a range of loading conditions.

  8. Biomechanics of milk extraction during breast-feeding.

    Science.gov (United States)

    Elad, David; Kozlovsky, Pavel; Blum, Omry; Laine, Andrew F; Po, Ming Jack; Botzer, Eyal; Dollberg, Shaul; Zelicovich, Mabel; Ben Sira, Liat

    2014-04-08

    How do infants extract milk during breast-feeding? We have resolved a century-long scientific controversy, whether it is sucking of the milk by subatmospheric pressure or mouthing of the nipple-areola complex to induce a peristaltic-like extraction mechanism. Breast-feeding is a dynamic process, which requires coupling between periodic motions of the infant's jaws, undulation of the tongue, and the breast milk ejection reflex. The physical mechanisms executed by the infant have been intriguing topics. We used an objective and dynamic analysis of ultrasound (US) movie clips acquired during breast-feeding to explore the tongue dynamic characteristics. Then, we developed a new 3D biophysical model of the breast and lactiferous tubes that enables the mimicking of dynamic characteristics observed in US imaging during breast-feeding, and thereby, exploration of the biomechanical aspects of breast-feeding. We have shown, for the first time to our knowledge, that latch-on to draw the nipple-areola complex into the infant mouth, as well as milk extraction during breast-feeding, require development of time-varying subatmospheric pressures within the infant's oral cavity. Analysis of the US movies clearly demonstrated that tongue motility during breast-feeding was fairly periodic. The anterior tongue, which is wedged between the nipple-areola complex and the lower lips, moves as a rigid body with the cycling motion of the mandible, while the posterior section of the tongue undulates in a pattern similar to a propagating peristaltic wave, which is essential for swallowing.

  9. A Biomechanical Modeling Study of the Effects of the Orbicularis Oris Muscle and Jaw Posture on Lip Shape

    Science.gov (United States)

    Stavness, Ian; Nazari, Mohammad Ali; Perrier, Pascal; Demolin, Didier; Payan, Yohan

    2013-01-01

    Purpose: The authors' general aim is to use biomechanical models of speech articulators to explore how possible variations in anatomical structure contribute to differences in articulatory strategies and phone systems across human populations. Specifically, they investigated 2 issues: (a) the link between lip muscle anatomy and variability in…

  10. BRAIN INJURY BIOMECHANICS IN REAL WORLD VEHICLE ACCIDENT USING MATHEMATICAL MODELS

    Institute of Scientific and Technical Information of China (English)

    YANG Jikuang; XU Wei; OTTE Dietmar

    2008-01-01

    This paper aims at investigating brain injury mechanisms and predicting head injuries in real world accidents. For this purpose, a 3D human head finite element model (HBM-head) was developed based on head-brain anatomy. The HBM head model was validated with two experimental tests. Then the head finite element(FE) model and a multi-body system (MBS) model were used to carry out reconstructions of real world vehicle-pedestrian accidents and brain injuries. The MBS models were used for calculating the head impact conditions in vehicle impacts. The HBM-head model was used for calculating the injury related physical parameters, such as intracranial pressure, stress, and strain. The calculated intracranial pressure and strain distribution were correlated with the injury outcomes observed from accidents. It is shown that this model can predict the intracranial biomechanical response and calculate the injury related physical parameters. The head FE model has good biofidelity and will be a valuable tool for the study of injury mechanisms and the tolerance level of the brain.

  11. A three-dimensional finite element model for biomechanical analysis of the hip.

    Science.gov (United States)

    Chen, Guang-Xing; Yang, Liu; Li, Kai; He, Rui; Yang, Bin; Zhan, Yan; Wang, Zhi-Jun; Yu, Bing-Nin; Jian, Zhe

    2013-11-01

    The objective of this study was to construct a three-dimensional (3D) finite element model of the hip. The images of the hip were obtained from Chinese visible human dataset. The hip model includes acetabular bone, cartilage, labrum, and bone. The cartilage of femoral head was constructed using the AutoCAD and Solidworks software. The hip model was imported into ABAQUS analysis system. The contact surface of the hip joint was meshed. To verify the model, the single leg peak force was loaded, and contact area of the cartilage and labrum of the hip and pressure distribution in these structures were observed. The constructed 3D hip model reflected the real hip anatomy. Further, this model reflected biomechanical behavior similar to previous studies. In conclusion, this 3D finite element hip model avoids the disadvantages of other construction methods, such as imprecision of cartilage construction and the absence of labrum. Further, it provides basic data critical for accurately modeling normal and abnormal loads, and the effects of abnormal loads on the hip.

  12. A joint computational respiratory neural network-biomechanical model for breathing and airway defensive behaviors

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    Russell eO'Connor

    2012-07-01

    Full Text Available Data-driven computational neural network models have been used to study mechanisms for generating the motor patterns for breathing and breathing related behaviors such as coughing. These models have commonly been evaluated in open loop conditions or with feedback of lung volume simply represented as a filtered version of phrenic motor output. Limitations of these approaches preclude assessment of the influence of mechanical properties of the musculoskeletal system and motivated development of a biomechanical model of the respiratory muscles, airway, and lungs using published measures from human subjects. Here we describe the model and some aspects of its behavior when linked to a computational brainstem respiratory network model for breathing and airway defensive behavior composed of discrete integrate and fire populations. The network incorporated multiple circuit paths and operations for tuning inspiratory drive suggested by prior work. Results from neuromechanical system simulations included generation of a eupneic-like breathing pattern and the observation that increased respiratory drive and operating volume result in higher peak flow rates during cough, even when the expiratory drive is unchanged, or when the expiratory abdominal pressure is unchanged. Sequential elimination of the model’s sources of inspiratory drive during cough also suggested a role for disinhibitory regulation via tonic expiratory neurons, a result that was subsequently supported by an analysis of in vivo data. Comparisons with antecedent models, discrepancies with experimental results, and some model limitations are noted.

  13. Hill’s and Huxley’s muscle models - tools for simulations in biomechanics

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    Jovanović Kosta

    2015-01-01

    Full Text Available Numerous mathematical models of human skeletal muscles have been developed. However, none of them is adopted as a general one and each of them is suggested for some specific purpose. This topic is essential in humanoid robotics, since we firstly need to understand how human moves and acts in order to exploit human movement patterns in robotics and design human like actuators. Simulations in biomechanics are intensively used in research of locomotion, safe human-robot interaction, development of novel robotic actuators, biologically inspired control algorithms, etc. This paper presents two widely adopted muscle models (Hill’s and Huxley’s model, elaborates their features and demonstrates trade-off between their accuracy and efficiency of computer simulations. The simulation setup contains mathematical representation of passive muscle structures as well as mathematical model of an elastic tendon as a series elastic actuation element. Advanced robot control techniques point out energy consumption as one of the key issues. Therefore, energy store and release mechanism in elastic elements in both tendon and muscle, based on the simulation models, are considered. [Projekat Ministarstva nauke Republike Srbije, br. TR35003 and br. OS175016

  14. A multi-scale biomechanical model based on the physiological structure and lignocellulose components of wheat straw.

    Science.gov (United States)

    Chen, Longjian; Li, Aiwei; He, Xueqin; Han, Lujia

    2015-11-20

    Biomechanical behavior is a fundamental property for the efficient utilization of wheat straw in such applications as fuel and renewable materials. Tensile experiments and lignocellulose analyses were performed on three types of wheat straw. A multi-scale finite element model composed of the microscopic model of the microfibril equivalent volume element and the macroscopic model of straw tissue was proposed based on the physiological structure and lignocellulose components of wheat straw. The tensile properties of wheat straw were simulated by ANSYS software. The predicted stress-strain data were compared with the observed data, and good correspondence was achieved for all three types of wheat straw. The validated multi-scale finite-element (FE) model was then used to investigate the effect of the lignocellulose components on the biomechanical properties of wheat straw. More than 80% of stress is carried by the cellulose fiber, whereas the strain is mainly carried by the amorphous cellulose.

  15. Biomechanical model for evaluation of pediatric upper extremity joint dynamics during wheelchair mobility.

    Science.gov (United States)

    Schnorenberg, Alyssa J; Slavens, Brooke A; Wang, Mei; Vogel, Lawrence C; Smith, Peter A; Harris, Gerald F

    2014-01-03

    Pediatric manual wheelchair users (MWU) require high joint demands on their upper extremity (UE) during wheelchair mobility, leading them to be at risk of developing pain and pathology. Studies have examined UE biomechanics during wheelchair mobility in the adult population; however, current methods for evaluating UE joint dynamics of pediatric MWU are limited. An inverse dynamics model is proposed to characterize three-dimensional UE joint kinematics and kinetics during pediatric wheelchair mobility using a SmartWheel instrumented handrim system. The bilateral model comprises thorax, clavicle, scapula, upper arm, forearm, and hand segments and includes the sternoclavicular, acromioclavicular, glenohumeral, elbow and wrist joints. A single 17 year-old male with a C7 spinal cord injury (SCI) was evaluated while propelling his wheelchair across a 15-meter walkway. The subject exhibited wrist extension angles up to 60°, large elbow ranges of motion and peak glenohumeral joint forces up to 10% body weight. Statistically significant asymmetry of the wrist, elbow, glenohumeral and acromioclavicular joints was detected by the model. As demonstrated, the custom bilateral UE pediatric model may provide considerable quantitative insight into UE joint dynamics to improve wheelchair prescription, training, rehabilitation and long-term care of children with orthopedic disabilities. Further research is warranted to evaluate pediatric wheelchair mobility in a larger population of children with SCI to investigate correlations to pain, function and transitional changes to adulthood.

  16. The biomechanics of erections: two- versus one-compartment pressurized vessel modeling of the penis.

    Science.gov (United States)

    Mohamed, Ahmed M; Erdman, Arthur G; Timm, Gerald W

    2010-12-01

    Previous biomechanical models of the penis simulated penile erections utilizing 2D geometry, simplified 3D geometry or made inaccurate assumptions altogether. These models designed the shaft of the penis as a one-compartment pressurized vessel fixed at one end when in reality it is a two-compartment pressurized vessel in which the compartments diverge as they enter the body and are fixed at two separate anatomic sites. This study utilizes the more anatomically correct two-compartment penile model to investigate erectile function. Simplified 2D and 3D models of the erect penis were developed using the finite element method with varying anatomical considerations for analyzing structural stresses, axial buckling, and lateral deformation. This study then validated the results by building and testing corresponding physical models. Finally, a more complex and anatomically accurate model of the penis was designed and analyzed. When subject to a lateral force of 0.5 N, the peak equivalent von Mises (EVM) stress in the two-compartment model increased by about 31.62%, while in the one-compartment model, the peak EVM stress increased by as high as 70.11%. The peak EVM stress was 149 kPa in the more complex and anatomically accurate penile model. When the perforated septum was removed, the peak EVM stress increased to 455 kPa. This study verified that there is significant difference between modeling the penis as a two- versus a one-compartment pressurized vessel. When subjected to external forces, a significant advantage was exhibited by two corporal based cavernosal bodies separated by a perforated septum as opposed to one corporal body. This is due to better structural integrity of the tunica albuginea when subjected to external forces.

  17. Validation of an experimental polyurethane model for biomechanical studies on implant supported prosthesis - tension tests

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    Mariane Miyashiro

    2011-06-01

    Full Text Available OBJECTIVES: The complexity and heterogeneity of human bone, as well as ethical issues, frequently hinder the development of clinical trials. The purpose of this in vitro study was to determine the modulus of elasticity of a polyurethane isotropic experimental model via tension tests, comparing the results to those reported in the literature for mandibular bone, in order to validate the use of such a model in lieu of mandibular bone in biomechanical studies. MATERIAL AND METHODS: Forty-five polyurethane test specimens were divided into 3 groups of 15 specimens each, according to the ratio (A/B of polyurethane reagents (PU-1: 1/0.5, PU-2: 1/1, PU-3: 1/1.5. RESULTS: Tension tests were performed in each experimental group and the modulus of elasticity values found were 192.98 MPa (SD=57.20 for PU-1, 347.90 MPa (SD=109.54 for PU-2 and 304.64 MPa (SD=25.48 for PU-3. CONCLUSION: The concentration of choice for building the experimental model was 1/1.

  18. Corneal biomechanics: a review.

    Science.gov (United States)

    Piñero, David P; Alcón, Natividad

    2015-03-01

    Biomechanics is often defined as 'mechanics applied to biology'. Due to the variety and complexity of the behaviour of biological structures and materials, biomechanics is better defined as the development, extension and application of mechanics for a better understanding of physiology and physiopathology and consequently for a better diagnosis and treatment of disease and injury. Different methods for the characterisation of corneal biomechanics are reviewed in detail, including those that are currently commercially available (Ocular Response Analyzer and CorVis ST). The clinical applicability of the parameters provided by these devices are discussed, especially in the fields of glaucoma, detection of ectatic disorders and orthokeratology. Likewise, other methods are also reviewed, such as Brillouin microscopy or dynamic optical coherence tomography and others with potential application to clinical practice but not validated for in vivo measurements, such as ultrasonic elastography. Advantages and disadvantages of all these techniques are described. Finally, the concept of biomechanical modelling is revised as well as the requirements for developing biomechanical models, with special emphasis on finite element modelling.

  19. Biomechanical studies in an ovine model of non-accidental head injury.

    Science.gov (United States)

    Anderson, R W G; Sandoz, B; Dutschke, J K; Finnie, J W; Turner, R J; Blumbergs, P C; Manavis, J; Vink, R

    2014-08-22

    This paper presents the head kinematics of a novel ovine model of non-accidental head injury (NAHI) that consists only of a naturalistic oscillating insult. Nine, 7-to-10-day-old anesthetized and ventilated lambs were subjected to manual shaking. Two six-axis motion sensors tracked the position of the head and torso, and a triaxial accelerometer measured head acceleration. Animals experienced 10 episodes of shaking over 30 min, and then remained under anesthesia for 6h until killed by perfusion fixation of the brain. Each shaking episode lasted for 20s resulting in about 40 cycles per episode. Each cycle typically consisted of three impulsive events that corresponded to specific phases of the head's motion; the most substantial of these were interactions typically with the lamb's own torso, and these generated accelerations of 30-70 g. Impulsive loading was not considered severe. Other kinematic parameters recorded included estimates of head power transfer, head-torso flexion, and rate of flexion. Several styles of shaking were also identified across episodes and subjects. Axonal injury, neuronal reaction and albumin extravasation were widely distributed in the hemispheric white matter, brainstem and at the craniocervical junction and to a much greater magnitude in lower body weight lambs that died. This is the first biomechanical description of a large animal model of NAHI in which repetitive naturalistic insults were applied, and that reproduced a spectrum of injury associated with NAHI.

  20. Theoretical Considerations and a Mathematical Model for the Analysis of the Biomechanical Response of Human Keratinized Oral Mucosa

    Directory of Open Access Journals (Sweden)

    Aikaterini Tsaira

    2016-08-01

    Full Text Available Removable complete and partial dentures are supported by the residual alveolar ridges consisting of mucosa, submucosa, periosteum and bone. An understanding of the biomechanical behavior of the oral mucosa is essential in order to improve the denture-bearing foundations for complete and partially edentulous patients. The purpose of this paper was to examine the biomechanical behavior of the soft tissues supporting a removable denture and develop a model for that reason. Keratinized oral mucosa blocks with their underlying bone were harvested from the maxillary palatal area adjacent to the edentulous ridges of a cadaver. The compressive response of the oral mucosa was tested by using atomic force microscopy. The specimens were first scanned in order their topography to be obtained. The mechanical properties of the specimens were tested using a single crystal silicon pyramidal tip, which traversed towards the keratinized oral mucosa specimens. Loading-unloading cycles were registered and four mathematical models were tested using MATLAB to note which one approximates the force-displacement curve as close as possible: a. spherical, b. conical, c. third order polynomial, d. Murphy (fourth order polynomial, non-linear Hertzian based. The third order polynomial model showed the best accuracy in representing the force-displacement data of the tested specimens. A model was developed in order to analyze the biomechanical behavior of the human oral keratinized mucosa and obtain information about its mechanical properties.

  1. A three-dimensional atlas of human tongue muscles.

    Science.gov (United States)

    Sanders, Ira; Mu, Liancai

    2013-07-01

    The human tongue is one of the most important yet least understood structures of the body. One reason for the relative lack of research on the human tongue is its complex anatomy. This is a real barrier to investigators as there are few anatomical resources in the literature that show this complex anatomy clearly. As a result, the diagnosis and treatment of tongue disorders lags behind that for other structures of the head and neck. This report intended to fill this gap by displaying the tongue's anatomy in multiple ways. The primary material used in this study was serial axial images of the male and female human tongue from the Visible Human (VH) Project of the National Library of Medicine. In addition, thick serial coronal sections of three human tongues were rendered translucent. The VH axial images were computer reconstructed into serial coronal sections and each tongue muscle was outlined. These outlines were used to construct a three-dimensional (3D) computer model of the tongue that allows each muscle to be seen in its in vivo anatomical position. The thick coronal sections supplement the 3D model by showing details of the complex interweaving of tongue muscles throughout the tongue. The graphics are perhaps the clearest guide to date to aid clinical or basic science investigators in identifying each tongue muscle in any part of the human tongue.

  2. Dinosaur biomechanics.

    Science.gov (United States)

    Alexander, R McNeill

    2006-08-07

    Biomechanics has made large contributions to dinosaur biology. It has enabled us to estimate both the speeds at which dinosaurs generally moved and the maximum speeds of which they may have been capable. It has told us about the range of postures they could have adopted, for locomotion and for feeding, and about the problems of blood circulation in sauropods with very long necks. It has made it possible to calculate the bite forces of predators such as Tyrannosaurus, and the stresses they imposed on its skull; and to work out the remarkable chewing mechanism of hadrosaurs. It has shown us how some dinosaurs may have produced sounds. It has enabled us to estimate the effectiveness of weapons such as the tail spines of Stegosaurus. In recent years, techniques such as computational tomography and finite element analysis, and advances in computer modelling, have brought new opportunities. Biomechanists should, however, be especially cautious in their work on animals known only as fossils. The lack of living specimens and even soft tissues oblige us to make many assumptions. It is important to be aware of the often wide ranges of uncertainty that result.

  3. Biomechanically inspired modelling of pedestrian-induced forces on laterally oscillating structures

    Science.gov (United States)

    Bocian, M.; Macdonald, J. H. G.; Burn, J. F.

    2012-07-01

    Despite considerable interest among engineers and scientists, bi-directional interaction between walking pedestrians and lively bridges has still not been well understood. In an attempt to bridge this gap a biomechanically inspired model of the human response to lateral bridge motion is presented and explored. The simple inverted pendulum model captures the key features of pedestrian lateral balance and the resulting forces on the structure. The forces include self-excited components that can be effectively modelled as frequency-dependent added damping and mass to the structure. The results of numerical simulations are in reasonable agreement with recent experimental measurements of humans walking on a laterally oscillating treadmill, and in very good agreement with measurements on full-scale bridges. In contrast to many other models of lateral pedestrian loading, synchronisation with the bridge motion is not involved. A parametric study of the model is conducted, revealing that as pedestrians slow down as a crowd becomes more dense, their resulting lower pacing rates generate larger self-excited forces. For typical pedestrian parameters, the potential to generate negative damping arises for any lateral bridge vibration frequency above 0.43 Hz, depending on the walking frequency. Stability boundaries of the combined pedestrian-structure system are presented in terms of the structural damping ratio and pedestrian-to-bridge mass ratio, revealing complex relations between damping demand and bridge and pedestrian frequencies, due to the added mass effect. Finally it is demonstrated that the model can produce simultaneous self-excited forces on multiple structural modes, and a realistic full simulation of a large number of pedestrians, walking randomly and interacting with a bridge, produces structural behaviour in very good agreement with site observations.

  4. Impact of modeling fluid-structure interaction in the computational analysis of aortic root biomechanics.

    Science.gov (United States)

    Sturla, Francesco; Votta, Emiliano; Stevanella, Marco; Conti, Carlo A; Redaelli, Alberto

    2013-12-01

    Numerical modeling can provide detailed and quantitative information on aortic root (AR) biomechanics, improving the understanding of AR complex pathophysiology and supporting the development of more effective clinical treatments. From this standpoint, fluid-structure interaction (FSI) models are currently the most exhaustive and potentially realistic computational tools. However, AR FSI modeling is extremely challenging and computationally expensive, due to the explicit simulation of coupled AR fluid dynamics and structural response, while accounting for complex morphological and mechanical features. We developed a novel FSI model of the physiological AR simulating its function throughout the entire cardiac cycle. The model includes an asymmetric MRI-based geometry, the description of aortic valve (AV) non-linear and anisotropic mechanical properties, and time-dependent blood pressures. By comparison to an equivalent finite element structural model, we quantified the balance between the extra information and the extra computational cost associated with the FSI approach. Tissue strains and stresses computed through the two approaches did not differ significantly. The FSI approach better captured the fast AV opening and closure, and its interplay with blood fluid dynamics within the Valsalva sinuses. It also reproduced the main features of in vivo AR fluid dynamics. However, the FSI simulation was ten times more computationally demanding than its structural counterpart. Hence, the FSI approach may be worth the extra computational cost when the tackled scenarios are strongly dependent on AV transient dynamics, Valsalva sinuses fluid dynamics in relation to coronary perfusion (e.g. sparing techniques), or AR fluid dynamic alterations (e.g. bicuspid AV).

  5. Computer Aided Modeling of Human Mastoid Cavity Biomechanics Using Finite Element Analysis

    Directory of Open Access Journals (Sweden)

    Chou Yuan-Fang

    2010-01-01

    Full Text Available The aim of the present study was to analyze the human mastoid cavity on sound transmission using finite element method. Pressure distributions in the external ear canal and middle ear cavity at different frequencies were demonstrated. Our results showed that, first, blocking the aditus improves middle ear sound transmission in the 1500- to 2500-Hz range and decreases displacement in frequencies below 1000 Hz when compared with the normal ear. Second, at frequencies lower than 1000 Hz, the acoustic pressures were almost uniformly distributed in the external ear canal and middle ear cavity. At high frequencies, higher than 1000 Hz, the pressure distribution varied along the external ear canal and middle ear cavity. Third, opening the aditus, the pressures difference in dB between the middle ear cavity and external ear canal were larger than those of the closed mastoid cavity in low frequency (<1000 Hz. Finally, there was no significant difference in the acoustic pressure between the oval window and round window is noted and increased by 5 dB by blocking the aditus. These results suggest that our complete FE model including the mastoid cavity is potentially useful and can provide more information in the study of middle ear biomechanics.

  6. Effects of excessive equatorial cold tongue bias on the projections of tropical Pacific climate change. Part I: the warming pattern in CMIP5 multi-model ensemble

    Science.gov (United States)

    Li, Gen; Xie, Shang-Ping; Du, Yan; Luo, Yiyong

    2016-12-01

    The excessive cold tongue error in the equatorial Pacific has persisted in several generations of climate models. Based on the historical simulations and Representative Concentration Pathway (RCP) 8.5 experiments in the Coupled Model Intercomparison Project phase 5 (CMIP5) multi-model ensemble (MME), this study finds that models with an excessive westward extension of cold tongue and insufficient equatorial western Pacific precipitation tend to project a weaker east-minus-west gradient of sea surface temperature (SST) warming along the equatorial Pacific under increased greenhouse gas (GHG) forcing. This La Niña-like error of tropical Pacific SST warming is consistent with our understanding of negative SST-convective feedback over the western Pacific warm pool. Based on this relationship between the present simulations and future projections, the present study applies an "observational constraint" of equatorial western Pacific precipitation to calibrate the projections of tropical Pacific climate change. After the corrections, CMIP5 models robustly project an El Niño-like warming pattern, with a MME mean increase by a factor of 2.3 in east-minus-west gradient of equatorial Pacific SST warming and reduced inter-model uncertainty. Corrections in projected changes in tropical precipitation and atmospheric circulation are physically consistent. This study suggests that a realistic cold tongue simulation would lead to a more reliable tropical Pacific climate projection.

  7. Effects of excessive equatorial cold tongue bias on the projections of tropical Pacific climate change. Part I: the warming pattern in CMIP5 multi-model ensemble

    Science.gov (United States)

    Li, Gen; Xie, Shang-Ping; Du, Yan; Luo, Yiyong

    2016-02-01

    The excessive cold tongue error in the equatorial Pacific has persisted in several generations of climate models. Based on the historical simulations and Representative Concentration Pathway (RCP) 8.5 experiments in the Coupled Model Intercomparison Project phase 5 (CMIP5) multi-model ensemble (MME), this study finds that models with an excessive westward extension of cold tongue and insufficient equatorial western Pacific precipitation tend to project a weaker east-minus-west gradient of sea surface temperature (SST) warming along the equatorial Pacific under increased greenhouse gas (GHG) forcing. This La Niña-like error of tropical Pacific SST warming is consistent with our understanding of negative SST-convective feedback over the western Pacific warm pool. Based on this relationship between the present simulations and future projections, the present study applies an "observational constraint" of equatorial western Pacific precipitation to calibrate the projections of tropical Pacific climate change. After the corrections, CMIP5 models robustly project an El Niño-like warming pattern, with a MME mean increase by a factor of 2.3 in east-minus-west gradient of equatorial Pacific SST warming and reduced inter-model uncertainty. Corrections in projected changes in tropical precipitation and atmospheric circulation are physically consistent. This study suggests that a realistic cold tongue simulation would lead to a more reliable tropical Pacific climate projection.

  8. SU-E-J-163: A Biomechanical Lung Model for Respiratory Motion Study

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X; Belcher, AH; Grelewicz, Z; Wiersma, RD [The University of Chicago, Chicago, IL (United States)

    2015-06-15

    Purpose: This work presents a biomechanical model to investigate the complex respiratory motion for the lung tumor tracking in radiosurgery by computer simulation. Methods: The models include networked massspring-dampers to describe the tumor motion, different types of surrogate signals, and the force generated by the diaphragm. Each mass-springdamper has the same mechanical structure and each model can have different numbers of mass-spring-dampers. Both linear and nonlinear stiffness parameters were considered, and the damping ratio was tuned in a range so that the tumor motion was over-damped (no natural tumor oscillation occurs without force from the diaphragm). The simulation was run by using ODE45 (ordinary differential equations by Runge-Kutta method) in MATLAB, and all time courses of motions and inputs (force) were generated and compared. Results: The curvature of the motion time courses around their peaks was sensitive to the damping ratio. Therefore, the damping ratio can be determined based on the clinical data of a high sampling rate. The peak values of different signals and the time the peaks occurred were compared, and it was found that the diaphragm force had a time lead over the tumor motion, and the lead time (0.1–0.4 seconds) depended on the distance between the tumor and the diaphragm. Conclusion: We reported a model based analysis approach for the spatial and temporal relation between the motion of the lung tumor and the surrogate signals. Due to the phase lead of the diaphragm in comparing with the lung tumor motion, the measurement of diaphragm motion (or its electromyography signal) can be used as a beam gating signal in radiosurgery, and it can also be an additional surrogate signal for better tumor motion tracking. The research is funded by the American Cancer Society (ACS) grant. The grant name is: Frameless SRS Based on Robotic Head Motion Cancellation. The grant number is: RSG-13-313-01-CCE.

  9. Cat tongue Velcro

    Science.gov (United States)

    Noel, Alexis; Martinez, Andrea; Jung, Hyewon; Tsai, Ting-Wen; Hu, David

    2016-11-01

    A cat's tongue is covered in an array of spines called papillae. These spines are thought to be used in grooming and rasping meat from bones of prey, although no mechanism has been given. We use high-speed video to film a cat removing cat food deeply wedged into a 3-D printed fur mat. We show that the spines on the tongue act as Velcro for particles. The tongue itself is highly elastic. As the cat presses it against a substrate, the tongue flattens and the spines separate. When the tongue is removed from the substrate the spines come together, wedging particles between them. This elasticity-driven entrapment permits the surface of the tongue to act as a carrier for hard to reach particles, and to increase the efficacy of grooming and feeding.

  10. Correlation between angle of incidence and sliding patterns of the tongue along the palate in Korean velar stops

    Science.gov (United States)

    Brunner, Jana; Fuchs, Susanne; Perrier, Pascal; Kim, Hyeon-Zoo

    2001-05-01

    In former studies, it has been hypothesized that the articulatory production of oral stops could result from the interaction between the tongue moving towards a virtual target located above the palate, and the palate. Velar stops, where the tongue slides along the palate during the occlusion phase, offer a nice experimental framework for further experimental assessments. Indeed, in the framework of the ``virtual target'' hypothesis, the sliding movement should be seen as the continuation of the movement before the occlusion, but constrained by the palate. Hence, relations should exist between the movement characteristics before contact and during the occlusion phase. To test this hypothesis three Korean speakers were recorded via EMA producing /aCV/ sequences with C=/g/, /k'/ and /kh/, V=/a/, /i/ or /u/. The angle between tongue trajectory just before the impact and palatal contour was estimated, and the amplitude of the sliding movement was measured. Preliminary results for two speakers show that these two variables correlate: The greater the angle, the larger the sliding movement. These findings are interpreted as supporting the ``virtual target'' hypothesis. This interpretation will be verified by simulations using a 2D biomechanical tongue model [Payan and Perrier, Speech Commun. 22 (1997)].

  11. Design of a Passive Exoskeleton for the Upper Extremity through Co-simulation with a Biomechanical Human Arm Model

    DEFF Research Database (Denmark)

    2013-01-01

    An approach of designing exoskeletons on the basis of simulation of the exoskeleton and a human body model is proposed in this paper. The new approach, addressing the problem of physical human-exoskeleton interactions, models and simulates the mechanics for both the exoskeleton and the human body......, which allows designers to analyze and evaluate an exoskeleton for its functioning, effectively. A simulation platform is developed by integrating a biomechanical model of human body and the exoskeleton. With the proposed approach, two types of exoskeletons with gravity compensating capability...

  12. The Effect of Phospholipids (Surfactant) on Adhesion and Biomechanical Properties of Tendon: A Rat Achilles Tendon Repair Model.

    Science.gov (United States)

    Dabak, T Kursat; Sertkaya, Omer; Acar, Nuray; Donmez, B Ozgur; Ustunel, Ismail

    2015-01-01

    Adhesion of the tendon is a major challenge for the orthopedic surgeon during tendon repair. Manipulation of biological environment is one of the concepts to prevent adhesion. Lots of biochemicals have been studied for this purpose. We aimed to determine the effect of phospholipids on adhesion and biomechanical properties of tendon in an animal tendon repair model. Seventy-two Wistar rats were divided into 4 groups. Achilles tendons of rats were cut and repaired. Phospholipids were applied at two different dosages. Tendon adhesion was determined histopathologically and biomechanical test was performed. At macroscopic evaluation of adhesion, there are statistically significant differences between multiple-dose phospholipid injection group and Control group and also hyaluronic acid group and Control group (p 0.008). Ultimate strength was highest at hyaluronic acid injection group and lowest at multiple-dose phospholipid injection group. Single-dose phospholipids (surfactant) application may have a beneficial effect on the tendon adhesion. Although multiple applications of phospholipids seem the most effective regime to reduce the tendon adhesion among groups, it deteriorated the biomechanical properties of tendon.

  13. Biomechanical comparison of anterior Caspar plate and three-level posterior fixation techniques in a human cadaveric model.

    Science.gov (United States)

    Traynelis, V C; Donaher, P A; Roach, R M; Kojimoto, H; Goel, V K

    1993-07-01

    Traumatic cervical spine injuries have been successfully stabilized with plates applied to the anterior vertebral bodies. Previous biomechanical studies suggest, however, that these devices may not provide adequate stability if the posterior ligaments are disrupted. To study this problem, the authors simulated a C-5 teardrop fracture with posterior ligamentous instability in human cadaveric spines. This model was used to compare the immediate biomechanical stability of anterior cervical plating, from C-4 to C-6, to that provided by a posterior wiring construct over the same levels. Stability was tested in six modes of motion: flexion, extension, right and left lateral bending, and right and left axial rotation. The injured/plate-stabilized spines were more stable than the intact specimens in all modes of testing. The injured/posterior-wired specimens were more stable than the intact spines in axial rotation and flexion. They were not as stable as the intact specimens in the lateral bending or extension testing modes. The data were normalized with respect to the motion of the uninjured spine and compared using repeated measures of analysis of variance, the results of which indicate that anterior plating provides significantly more stability in extension and lateral bending than does posterior wiring. The plate was more stable than the posterior construct in flexion loading; however, the difference was not statistically significant. The two constructs provide similar stability in axial rotation. This study provides biomechanical support for the continued use of bicortical anterior plate fixation in the setting of traumatic cervical spine instability.

  14. Patient-Specific Biomechanical Modeling for Guidance During Minimally-Invasive Hepatic Surgery.

    Science.gov (United States)

    Plantefève, Rosalie; Peterlik, Igor; Haouchine, Nazim; Cotin, Stéphane

    2016-01-01

    During the minimally-invasive liver surgery, only the partial surface view of the liver is usually provided to the surgeon via the laparoscopic camera. Therefore, it is necessary to estimate the actual position of the internal structures such as tumors and vessels from the pre-operative images. Nevertheless, such task can be highly challenging since during the intervention, the abdominal organs undergo important deformations due to the pneumoperitoneum, respiratory and cardiac motion and the interaction with the surgical tools. Therefore, a reliable automatic system for intra-operative guidance requires fast and reliable registration of the pre- and intra-operative data. In this paper we present a complete pipeline for the registration of pre-operative patient-specific image data to the sparse and incomplete intra-operative data. While the intra-operative data is represented by a point cloud extracted from the stereo-endoscopic images, the pre-operative data is used to reconstruct a biomechanical model which is necessary for accurate estimation of the position of the internal structures, considering the actual deformations. This model takes into account the patient-specific liver anatomy composed of parenchyma, vascularization and capsule, and is enriched with anatomical boundary conditions transferred from an atlas. The registration process employs the iterative closest point technique together with a penalty-based method. We perform a quantitative assessment based on the evaluation of the target registration error on synthetic data as well as a qualitative assessment on real patient data. We demonstrate that the proposed registration method provides good results in terms of both accuracy and robustness w.r.t. the quality of the intra-operative data.

  15. Modeling the Biomechanical Influence of Epilaryngeal Stricture on the Vocal Folds: A Low-Dimensional Model of Vocal-Ventricular Fold Coupling

    Science.gov (United States)

    Moisik, Scott R.; Esling, John H.

    2014-01-01

    Purpose: Physiological and phonetic studies suggest that, at moderate levels of epilaryngeal stricture, the ventricular folds impinge upon the vocal folds and influence their dynamical behavior, which is thought to be responsible for constricted laryngeal sounds. In this work, the authors examine this hypothesis through biomechanical modeling.…

  16. The Impact of the Atlantic Cold Tongue on West African Monsoon Onset in Regional Model Simulations for 1998-2002

    Science.gov (United States)

    Druyan, Leonard M.; Fulakeza, Matthew B.

    2014-01-01

    The Atlantic cold tongue (ACT) develops during spring and early summer near the Equator in the Eastern Atlantic Ocean and Gulf of Guinea. The hypothesis that the ACT accelerates the timing of West African monsoon (WAM) onset is tested by comparing two regional climate model (RM3) simulation ensembles. Observed sea surface temperatures (SST) that include the ACT are used to force a control ensemble. An idealized, warm SST perturbation is designed to represent lower boundary forcing without the ACT for the experiment ensemble. Summer simulations forced by observed SST and reanalysis boundary conditions for each of five consecutive years are compared to five parallel runs forced by SST with the warm perturbation. The article summarizes the sequence of events leading to the onset of the WAM in the Sahel region. The representation of WAM onset in RM3 simulations is examined and compared to Tropical Rainfall Measuring Mission (TRMM), Global Precipitation Climatology Project (GPCP) and reanalysis data. The study evaluates the sensitivity of WAM onset indicators to the presence of the ACT by analysing the differences between the two simulation ensembles. Results show that the timing of major rainfall events and therefore theWAM onset in the Sahel are not sensitive to the presence of the ACT. However, the warm SST perturbation does increase downstream rainfall rates over West Africa as a consequence of enhanced specific humidity and enhanced northward moisture flux in the lower troposphere.

  17. Keys to an open lock : Subject specific biomechanical modelling of luxations of the human temporomandibular joint

    NARCIS (Netherlands)

    Tuijt, M.

    2017-01-01

    In this thesis, the aims are to: • increase the understanding of the interplay of morphological aspects, such as joint shape and muscle orientation, in open locks of the human temporomandibular joint. • increase the understanding of the biomechanics behind open locks of the temporomandibular joint.

  18. Comment on "Use of deterministic models in sports and exercise biomechanics research" by Chow and Knudson (2011).

    Science.gov (United States)

    Glazier, Paul S; Robins, Matthew T

    2012-03-01

    Although deterministic models may provide a useful starting point for sports biomechanists examining the mechanical aspects of athletic performance, they have inherent weaknesses that limit their proctical application. Specifically, their inability to provide substantive information about coordinative movement patterns or 'technique' suggests that sports biomechanists must explore alternative paradigms and theoretical frameworks if they are to fulfil their main aims of improving performance and reducing injury risk. We believe that dynamical systems theory and its associated analytical tools can provide a useful adjunct to more traditional paradigms in sport biomechanics, such as deterministic modelling, which have only made a limit contribution to the enhancement of knowledge.

  19. Bridging the gap between cadaveric and in vivo experiments: a biomechanical model evaluating thumb-tip endpoint forces.

    Science.gov (United States)

    Wohlman, Sarah J; Murray, Wendy M

    2013-03-15

    The thumb is required for a majority of tasks of daily living. Biomechanical modeling is a valuable tool, with the potential to help us bridge the gap between our understanding of the mechanical actions of individual thumb muscles, derived from anatomical cadaveric experiments, and our understanding of how force is produced by the coordination of all of the thumb muscles, derived from studies involving human subjects. However, current biomechanical models do not replicate muscle force production at the thumb-tip. We hypothesized that accurate representations of the axes of rotation of the thumb joints were necessary to simulate the magnitude of endpoint forces produced by human subjects. We augmented a musculoskeletal model with axes of rotation derived from experimental measurements (Holzbaur et al., 2005) by defining muscle-tendon paths and maximum isometric force-generating capacity for the five intrinsic muscles. We then evaluated if this augmented model replicated a broad range of experimental data from the literature and identified which parameters most influenced model performance. The simulated endpoint forces generated by the combined action of all thumb muscles in our model yielded comparable forces in magnitude to those produced by nonimpaired subjects. A series of 8 sets of Monte Carlo simulations demonstrated that the difference in the axes of rotation of the thumb joints between studies best explains the improved performance of our model relative to previous work. In addition, we demonstrate that the endpoint forces produced by individual muscles cannot be replicated with existing experimental data describing muscle moment arms.

  20. Influence of Orthotropy on Biomechanics of Peri-Implant Bone in Complete Mandible Model with Full Dentition

    Directory of Open Access Journals (Sweden)

    Xi Ding

    2014-01-01

    Full Text Available Objective. The study was to investigate the impact of orthotropic material on the biomechanics of dental implant, based on a detailed mandible with high geometric and mechanical similarity. Materials and Methods. Multiple data sources were used to elaborate detailed biological structures and implant CAD models. In addition, an extended orthotropic material assignment methodology based on harmonic fields was used to handle the alveolar ridge region to generate compatible orthotropic fields. The influence of orthotropic material was compared with the commonly used isotropic model and simplified orthotropic model. Results. The simulation results showed that the values of stress and strain on the implant-bone interface almost increased in the orthotropic model compared to the isotropic case, especially for the cancellous bone. However, the local stress concentration was more obvious in the isotropic case compared to that in orthotropic case. The simple orthotropic model revealed irregular stress and strain distribution, compared to the isotropic model and the real orthotropic model. The influence of orthotropy was little on the implant, periodontal ligament, tooth enamel, and dentin. Conclusion. The orthotropic material has significant effect on stress and strain of implant-bone interface in the mandible, compared with the isotropic simulation. Real orthotropic mechanical properties of mandible should be emphasized in biomechanical studies of dental implants.

  1. Beware the black box: investigating the sensitivity of FEA simulations to modelling factors in comparative biomechanics.

    Science.gov (United States)

    Walmsley, Christopher W; McCurry, Matthew R; Clausen, Phillip D; McHenry, Colin R

    2013-01-01

    Finite element analysis (FEA) is a computational technique of growing popularity in the field of comparative biomechanics, and is an easily accessible platform for form-function analyses of biological structures. However, its rapid evolution in recent years from a novel approach to common practice demands some scrutiny in regards to the validity of results and the appropriateness of assumptions inherent in setting up simulations. Both validation and sensitivity analyses remain unexplored in many comparative analyses, and assumptions considered to be 'reasonable' are often assumed to have little influence on the results and their interpretation. HERE WE REPORT AN EXTENSIVE SENSITIVITY ANALYSIS WHERE HIGH RESOLUTION FINITE ELEMENT (FE) MODELS OF MANDIBLES FROM SEVEN SPECIES OF CROCODILE WERE ANALYSED UNDER LOADS TYPICAL FOR COMPARATIVE ANALYSIS: biting, shaking, and twisting. Simulations explored the effect on both the absolute response and the interspecies pattern of results to variations in commonly used input parameters. Our sensitivity analysis focuses on assumptions relating to the selection of material properties (heterogeneous or homogeneous), scaling (standardising volume, surface area, or length), tooth position (front, mid, or back tooth engagement), and linear load case (type of loading for each feeding type). Our findings show that in a comparative context, FE models are far less sensitive to the selection of material property values and scaling to either volume or surface area than they are to those assumptions relating to the functional aspects of the simulation, such as tooth position and linear load case. Results show a complex interaction between simulation assumptions, depending on the combination of assumptions and the overall shape of each specimen. Keeping assumptions consistent between models in an analysis does not ensure that results can be generalised beyond the specific set of assumptions used. Logically, different comparative datasets would

  2. An investigation of jogging biomechanics using the full-body lumbar spine model: Model development and validation.

    Science.gov (United States)

    Raabe, Margaret E; Chaudhari, Ajit M W

    2016-05-03

    The ability of a biomechanical simulation to produce results that can translate to real-life situations is largely dependent on the physiological accuracy of the musculoskeletal model. There are a limited number of freely-available, full-body models that exist in OpenSim, and those that do exist are very limited in terms of trunk musculature and degrees of freedom in the spine. Properly modeling the motion and musculature of the trunk is necessary to most accurately estimate lower extremity and spinal loading. The objective of this study was to develop and validate a more physiologically accurate OpenSim full-body model. By building upon three previously developed OpenSim models, the full-body lumbar spine (FBLS) model, comprised of 21 segments, 30 degrees-of-freedom, and 324 musculotendon actuators, was developed. The five lumbar vertebrae were modeled as individual bodies, and coupled constraints were implemented to describe the net motion of the spine. The eight major muscle groups of the lumbar spine were modeled (rectus abdominis, external and internal obliques, erector spinae, multifidus, quadratus lumborum, psoas major, and latissimus dorsi), and many of these muscle groups were modeled as multiple fascicles allowing the large muscles to act in multiple directions. The resulting FBLS model׳s trunk muscle geometry, maximal isometric joint moments, and simulated muscle activations compare well to experimental data. The FBLS model will be made freely available (https://simtk.org/home/fullbodylumbar) for others to perform additional analyses and develop simulations investigating full-body dynamics and contributions of the trunk muscles to dynamic tasks.

  3. Image Analysis for Tongue Characterization

    Institute of Scientific and Technical Information of China (English)

    SHENLansun; WEIBaoguo; CAIYiheng; ZHANGXinfeng; WANGYanqing; CHENJing; KONGLingbiao

    2003-01-01

    Tongue diagnosis is one of the essential methods in traditional Chinese medical diagnosis. The ac-curacy of tongue diagnosis can be improved by tongue char-acterization. This paper investigates the use of image anal-ysis techniques for tongue characterization by evaluating visual features obtained from images. A tongue imaging and analysis instrument (TIAI) was developed to acquire digital color tongue images. Several novel approaches are presented for color calibration, tongue area segmentation,quantitative analysis and qualitative description for the colors of tongue and its coating, the thickness and moisture of coating and quantification of the cracks of the toilgue.The overall accuracy of the automatic analysis of the colors of tongue and the thickness of tongue coating exceeds 85%.This work shows the promising future of tongue character-ization.

  4. A novel biomechanical analysis of gait changes in the MPTP mouse model of Parkinson’s disease

    Directory of Open Access Journals (Sweden)

    Werner J. Geldenhuys

    2015-08-01

    Full Text Available Parkinson’s disease (PD is an age-associated neurodegenerative disorder hallmarked by a loss of mesencephalic dopaminergic neurons. Accurate recapitulation of the PD movement phenotype in animal models of the disease is critical for understanding disease etiology and developing novel therapeutic treatments. However, most existing behavioral assays currently applied to such animal models fail to adequately detect and subsequently quantify the subtle changes associated with the progressive stages of PD. In this study, we used a video-based analysis system to develop and validate a novel protocol for tracking locomotor performance in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP mouse model of PD. We anticipated that (1 treated mice should use slower, shorter, and less frequent strides and (2 that gait deficits should monotonically increase following MPTP administration, as the effects of neurodegeneration become manifest. Video-based biomechanical analyses, utilizing behavioral measures motivated by the comparative biomechanics literature, were used to quantify gait dynamics over a seven-day period following MPTP treatment. Analyses revealed shuffling behaviors consistent with the gait symptoms of advanced PD in humans. Here we also document dramatic gender-based differences in locomotor performance during the progression of the MPTP-induced lesion, despite male and female mice showing similar losses of striatal dopaminergic cells following MPTP administration. Whereas female mice appeared to be protected against gait deficits, males showed multiple changes in gait kinematics, consistent with the loss of locomotor agility and stability. Overall, these data show that the novel video analysis protocol presented here is a robust method capable of detecting subtle changes in gait biomechanics in a mouse model of PD. Our findings indicate that this method is a useful means by which to easily and economically screen preclinical therapeutic

  5. Artificial neural networks to predict 3D spinal posture in reaching and lifting activities; Applications in biomechanical models.

    Science.gov (United States)

    Gholipour, A; Arjmand, N

    2016-09-06

    Spinal posture is a crucial input in biomechanical models and an essential factor in ergonomics investigations to evaluate risk of low back injury. In vivo measurement of spinal posture through the common motion capture techniques is limited to equipped laboratories and thus impractical for workplace applications. Posture prediction models are therefore considered indispensable tools. This study aims to investigate the capability of artificial neural networks (ANNs) in predicting the three-dimensional posture of the spine (S1, T12 and T1 orientations) in various activities. Two ANNs were trained and tested using measurements from spinal postures of 40 male subjects by an inertial tracking device in various static reaching and lifting (of 5kg) activities. Inputs of each ANN were position of the hand load and body height, while outputs were rotations of the three foregoing segments relative to their initial orientation in the neutral upright posture. Effect of posture prediction errors on the estimated spinal loads in symmetric reaching activities was also investigated using a biomechanical model. Results indicated that both trained ANNs could generate outputs (three-dimensional orientations of the segments) from novel sets of inputs that were not included in the training processes (root-mean-squared-error (RMSE)0.95). A graphic user interface was designed and made available to facilitate use of the ANNs. The difference between the mean of each measured angle in a reaching task and the corresponding angle in a lifting task remained smaller than 8°. Spinal loads estimated by the biomechanical model based on the predicted postures were on average different by < 12% from those estimated based on the exact measured postures (RMSE=173 and 35N for the L5-S1 compression and shear loads, respectively).

  6. Muscle-skeletal model of the thigh: a tool for understanding the biomechanics of gait in patients with cerebral palsy

    Science.gov (United States)

    Ravera, Emiliano Pablo; Catalfamo Formento, Paola Andrea; José Crespo, Marcos; Andrés Braidot, Ariel

    2011-12-01

    Cerebral Palsy represents the most common cause of physical disability in modern world and within the pediatrics orthopedics units. The gait analysis provides great contributions to the understanding of gait disorders in CP. Giving a more comprehensive treatment plan, including or excluding surgical procedures that can potentially decrease the number of surgical interventions in the life of these patients. Recommendations for orthopedic surgery may be based on a quantitative description of how to alter the properties probably muscle force generation, and how this affects the action of the muscle to determine how these muscles, impaired by disease or surgery, contributing to the movement of the segments of the limb during crouch gait. So the causes and appropriate treatment of gait abnormalities are difficult to determine because the movements generated by the muscular forces of these patients are not clearly understood. A correct determination of the etiology of abnormal patterns of the knee is the key to select the appropriate therapy, presenting a major challenge at present since there is no theoretical basis to determine the biomechanical causes of abnormal gait of these patients. The potential and necessity of using correct biomechanical models that consistently study the abnormalities becomes clear. Reinforcing and correcting a simple gait analysis and eliminating the unknowns when selecting the appropriate treatment is crucial in clinical settings. In this paper a computer muscle-skeletal model is proposed. The model represents a person's thigh simulating the six most representative muscles and joints of the hip and knee. In this way you can have a better understanding of gait abnormalities present in these patients. So the quality of these estimates of individual muscle dynamics facilitate better understanding of the biomechanics of gait pathologies helping to reach better diagnosis prior to surgery and rehabilitation treatments.

  7. Tongue Pressure Modulation for Initial Gel Consistency in a Different Oral Strategy

    Science.gov (United States)

    Yokoyama, Sumiko; Hori, Kazuhiro; Tamine, Ken-ichi; Fujiwara, Shigehiro; Inoue, Makoto; Maeda, Yoshinobu; Funami, Takahiro; Ishihara, Sayaka; Ono, Takahiro

    2014-01-01

    Background In the recent hyper-aged societies of developed countries, the market for soft diets for patients with dysphagia has been growing and numerous jelly-type foods have become available. However, interrelationships between the biomechanics of oral strategies and jelly texture remain unclear. The present study investigated the influence of the initial consistency of jelly on tongue motor kinetics in different oral strategies by measuring tongue pressure against the hard palate. Methods Jellies created as a mixture of deacylated gellan gum and psyllium seed gum with different initial consistencies (hard, medium or soft) were prepared as test foods. Tongue pressure production while ingesting 5 ml of jelly using different oral strategies (Squeezing or Mastication) was recorded in eight healthy volunteers using an ultra-thin sensor sheet system. Maximal magnitude, duration and total integrated values (tongue work) of tongue pressure for size reduction and swallowing in each strategy were compared among initial consistencies of jelly, and between Squeezing and Mastication. Results In Squeezing, the tongue performed more work for size reduction with increasing initial consistency of jelly by modulating both the magnitude and duration of tongue pressure over a wide area of hard palate, but tongue work for swallowing increased at the posterior-median and circumferential parts by modulating only the magnitude of tongue pressure. Conversely, in Mastication, the tongue performed more work for size reduction with increasing initial consistency of jelly by modulating both magnitude and duration of tongue pressure mainly at the posterior part of the hard palate, but tongue work as well as other tongue pressure parameters for swallowing showed no differences by type of jelly. Conclusions These results reveal fine modulations in tongue-palate contact according to the initial consistency of jelly and oral strategies. PMID:24643054

  8. The biomechanical modelling of non-ballistic skin wounding: blunt-force injury.

    Science.gov (United States)

    Whittle, Kelly; Kieser, Jules; Ichim, Ionut; Swain, Michael; Waddell, Neil; Livingstone, Vicki; Taylor, Michael

    2008-01-01

    Knowledge of the biomechanical dynamics of blunt force trauma is indispensable for forensic reconstruction of a wounding event. In this study, we describe and interpret wound features on a synthetic skin model under defined laboratory conditions. To simulate skin and the sub-dermal tissues we used open-celled polyurethane sponge (foam), covered by a silicone layer. A drop tube device with three tube lengths (300, 400, and 500 mm), each secured to a weighted steel scaffold and into which a round, 5-kg Federal dumbbell of length 180 mm and diameter 8 cm was placed delivered blows of known impact. To calculate energy and velocity at impact the experimental set-up was replicated using rigid-body dynamics and motion simulation software. We soaked each foam square in 500 mL water, until fully saturated, immediately before placing it beneath the drop tube. We then recorded and classified both external and internal lacerations. The association between external wounding rates and the explanatory variables sponge type, sponge thickness, and height were investigated using Poisson regression. Tears (lacerations) of the silicone skin layer resembled linear lacerations seen in the clinical literature and resulted from only 48.6% of impacts. Poisson regression showed there was no significant difference between the rate of external wounding for different sponge types (P = 0.294) or different drop heights (P = 0.276). Most impacts produced "internal wounds" or subsurface cavitation (96%). There were four internal "wound" types; Y-shape (53%), linear (25%), stellate (16%), and double crescent (6%). The two-way interaction height by sponge type was statistically significant in the analysis of variance model (P = 0.035). The other two-way interactions; height by thickness and sponge type by thickness, were also bordering on statistical significance (P = 0.061 and P = 0.071, respectively). The observation that external wounds were present for less than half of impacts only, but that

  9. A GPU based high-resolution multilevel biomechanical head and neck model for validating deformable image registration

    Energy Technology Data Exchange (ETDEWEB)

    Neylon, J., E-mail: jneylon@mednet.ucla.edu; Qi, X.; Sheng, K.; Low, D. A.; Kupelian, P.; Santhanam, A. [Department of Radiation Oncology, University of California Los Angeles, 200 Medical Plaza, #B265, Los Angeles, California 90095 (United States); Staton, R.; Pukala, J.; Manon, R. [Department of Radiation Oncology, M.D. Anderson Cancer Center, Orlando, 1440 South Orange Avenue, Orlando, Florida 32808 (United States)

    2015-01-15

    Purpose: Validating the usage of deformable image registration (DIR) for daily patient positioning is critical for adaptive radiotherapy (RT) applications pertaining to head and neck (HN) radiotherapy. The authors present a methodology for generating biomechanically realistic ground-truth data for validating DIR algorithms for HN anatomy by (a) developing a high-resolution deformable biomechanical HN model from a planning CT, (b) simulating deformations for a range of interfraction posture changes and physiological regression, and (c) generating subsequent CT images representing the deformed anatomy. Methods: The biomechanical model was developed using HN kVCT datasets and the corresponding structure contours. The voxels inside a given 3D contour boundary were clustered using a graphics processing unit (GPU) based algorithm that accounted for inconsistencies and gaps in the boundary to form a volumetric structure. While the bony anatomy was modeled as rigid body, the muscle and soft tissue structures were modeled as mass–spring-damper models with elastic material properties that corresponded to the underlying contoured anatomies. Within a given muscle structure, the voxels were classified using a uniform grid and a normalized mass was assigned to each voxel based on its Hounsfield number. The soft tissue deformation for a given skeletal actuation was performed using an implicit Euler integration with each iteration split into two substeps: one for the muscle structures and the other for the remaining soft tissues. Posture changes were simulated by articulating the skeletal structure and enabling the soft structures to deform accordingly. Physiological changes representing tumor regression were simulated by reducing the target volume and enabling the surrounding soft structures to deform accordingly. Finally, the authors also discuss a new approach to generate kVCT images representing the deformed anatomy that accounts for gaps and antialiasing artifacts that may

  10. Development and validation of Raman spectroscopic classification models to discriminate tongue squamous cell carcinoma from non-tumorous tissue

    NARCIS (Netherlands)

    F.L.J. Cals; S. Koljenovic (Senada); J.A.U. Hardillo (José); R.J. Baatenburg de Jong (Robert Jan); T.C. Bakker Schut (Tom); G.J. Puppels (Gerwin)

    2016-01-01

    markdownabstractBackground Currently, up to 85% of the oral resection specimens have inadequate resection margins, of which the majority is located in the deeper soft tissue layers. The prognosis of patients with oral cavity squamous cell carcinoma (OCSCC) of the tongue is negatively affected by the

  11. Assessing Trailer Material Handling Tasks: Biomechanical Modeling, Posture Categorization, Physiological Measure, and Subjective Rating

    OpenAIRE

    Honaker, Ronald E.

    1996-01-01

    Many variations of conveyor, facility, and trailer designs are available to aid the human operator in manual materials handling (MMH). This thesis describes an investigation to determine which of four different designs used in trailer MMH place the least physical stress on the human operator when unloading materials. Each trailer MMH design was evaluated by the criteria of biomechanical loading, working posture, physiological measure, and subjective rating ...

  12. Geographic Tongue in Monozygotic Twins

    OpenAIRE

    Shekhar M, Guna

    2014-01-01

    This article discusses a case of 5-year-old girl monozygotic twins who were suffering from geographic tongue (GT), a benign inflammatory disorder of the tongue which is characterized by circinate, irregular erythematous lesions on the dorsum and lateral borders of the tongue caused by loss of filiform papillae of the tongue epithelium. Whilst geographic tongue is a common entity, reports on this condition are uncommon in the literature. To best of our knowledge, this is the first report which...

  13. Atlas-Based Automatic Generation of Subject-Specific Finite Element Tongue Meshes.

    Science.gov (United States)

    Bijar, Ahmad; Rohan, Pierre-Yves; Perrier, Pascal; Payan, Yohan

    2016-01-01

    Generation of subject-specific 3D finite element (FE) models requires the processing of numerous medical images in order to precisely extract geometrical information about subject-specific anatomy. This processing remains extremely challenging. To overcome this difficulty, we present an automatic atlas-based method that generates subject-specific FE meshes via a 3D registration guided by Magnetic Resonance images. The method extracts a 3D transformation by registering the atlas' volume image to the subject's one, and establishes a one-to-one correspondence between the two volumes. The 3D transformation field deforms the atlas' mesh to generate the subject-specific FE mesh. To preserve the quality of the subject-specific mesh, a diffeomorphic non-rigid registration based on B-spline free-form deformations is used, which guarantees a non-folding and one-to-one transformation. Two evaluations of the method are provided. First, a publicly available CT-database is used to assess the capability to accurately capture the complexity of each subject-specific Lung's geometry. Second, FE tongue meshes are generated for two healthy volunteers and two patients suffering from tongue cancer using MR images. It is shown that the method generates an appropriate representation of the subject-specific geometry while preserving the quality of the FE meshes for subsequent FE analysis. To demonstrate the importance of our method in a clinical context, a subject-specific mesh is used to simulate tongue's biomechanical response to the activation of an important tongue muscle, before and after cancer surgery.

  14. Tongue diagnosis:relationship between sublingual tongue morphology in three tongue protrusion angles and menstrual clinical symptoms

    Institute of Scientific and Technical Information of China (English)

    Tim Hideaki Tanaka

    2015-01-01

    OBJECTIVE:The morphological and color characteristics of the tongue sublingual veins (SLVs) can manifest differently within the subjects, depending on the way their tongue is curled upward. This study was conducted in order to investigate the clinical relevancy of tongue SLV diagnosis in relation to menstrual clinical symptoms (pain, clots, heavy, and scanty), using three different inspection procedures (IP1, IP2, and IP3). METHODS: Three-hundred and seventy-seven female patients were asked to stick out their tongues in three speciifc ways which were intended to create different tongue protrusion angles. The SLV parameters for thickness (TK), length (LE), color (CL), shape (SP), and nodules (ND) were then evaluated. RESULTS: According to the results of the Waldχ2 test, IP1 provides the best model for pain (R2 = 0.155), IP3 for clots (R2 = 0.437), IP2 for heavy (R2 = 0.268), and scanty (R2 = 0.192). Abnormal SLV diagnostic parameters were most strongly associated with the clinical symptom of clots (R2= 0.492). CONCLUSION: While the study showed the relations between tongue SLV features and menstrual clinical symptoms, as wel it showed that IP2 was the best overal predictor for the symptomatic indexes used in this study, and using one particular SLV inspection procedure may not be sufifcient. The application of a particular inspection method alone may cause under- or over-estimation of SLV abnormalities.

  15. Biomechanics of the chick embryonic heart outflow tract at HH18 using 4D optical coherence tomography imaging and computational modeling.

    Directory of Open Access Journals (Sweden)

    Aiping Liu

    Full Text Available During developmental stages, biomechanical stimuli on cardiac cells modulate genetic programs, and deviations from normal stimuli can lead to cardiac defects. Therefore, it is important to characterize normal cardiac biomechanical stimuli during early developmental stages. Using the chicken embryo model of cardiac development, we focused on characterizing biomechanical stimuli on the Hamburger-Hamilton (HH 18 chick cardiac outflow tract (OFT, the distal portion of the heart from which a large portion of defects observed in humans originate. To characterize biomechanical stimuli in the OFT, we used a combination of in vivo optical coherence tomography (OCT imaging, physiological measurements and computational fluid dynamics (CFD modeling. We found that, at HH18, the proximal portion of the OFT wall undergoes larger circumferential strains than its distal portion, while the distal portion of the OFT wall undergoes larger wall stresses. Maximal wall shear stresses were generally found on the surface of endocardial cushions, which are protrusions of extracellular matrix onto the OFT lumen that later during development give rise to cardiac septa and valves. The non-uniform spatial and temporal distributions of stresses and strains in the OFT walls provide biomechanical cues to cardiac cells that likely aid in the extensive differential growth and remodeling patterns observed during normal development.

  16. Dinosaur biomechanics

    OpenAIRE

    Alexander, R. McNeill

    2006-01-01

    Biomechanics has made large contributions to dinosaur biology. It has enabled us to estimate both the speeds at which dinosaurs generally moved and the maximum speeds of which they may have been capable. It has told us about the range of postures they could have adopted, for locomotion and for feeding, and about the problems of blood circulation in sauropods with very long necks. It has made it possible to calculate the bite forces of predators such as Tyrannosaurus, and the stresses they imp...

  17. The Tongue and Quill

    Science.gov (United States)

    2007-11-02

    many sources; e.g., official records, private communications and automated transactions. emoticons —Facial expressions drawn on the computer (see page...AFH 33-337 30 June 1997 The Tongue and Quill Communication is an essential tool for the twenty-first century Air Force Report Documentation Page... Communications and Information THE TONGUE AND QUILL Supersedes AFH 37-137, 31 August 1994 Certified by: ACSC/DEX (Lt Col Kermit Phelps) OPR: ACSC/DEXP (Mrs

  18. Convergence of macroscopic tongue anatomy in ruminants and scaling relationships with body mass or tongue length.

    Science.gov (United States)

    Meier, Andrea R; Schmuck, Ute; Meloro, Carlo; Clauss, Marcus; Hofmann, Reinhold R

    2016-03-01

    Various morphological measures demonstrate convergent evolution in ruminants with their natural diet, in particular with respect to the browser/grazer dichotomy. Here, we report quantitative macroanatomical measures of the tongue (length and width of specific parts) of 65 ruminant species and relate them to either body mass (BM) or total tongue length, and to the percentage of grass in the natural diet (%grass). Models without and with accounting for the phylogenetic structures of the dataset were used, and models were ranked using Akaike's Information Criterion. Scaling relationships followed geometric principles, that is, length measures scaled with BM to the power of 0.33. Models that used tongue length rather than BM as a body size proxy were consistently ranked better, indicating that using size proxies that are less susceptible to a wider variety of factors (such as BM that fluctuates with body condition) should be attempted whenever possible. The proportion of the freely mobile tongue tip of the total tongue (and hence also the corpus length) was negatively correlated to %grass, in accordance with concepts that the feeding mechanism of browsers requires more mobile tongues. It should be noted that some nonbrowsers, such as cattle, use a peculiar mechanism for grazing that also requires long, mobile tongues, but they appear to be exceptions. A larger corpus width with increasing %grass corresponds to differences in snout shape with broader snouts in grazers. The Torus linguae is longer with increasing %grass, a finding that still warrants functional interpretation. This study shows that tongue measures covary with diet in ruminants. In contrast, the shape of the tongue (straight or "hourglass-shaped" as measured by the ratio of the widest and smallest corpus width) is unrelated to diet and is influenced strongly by phylogeny.

  19. Influence of visual observational conditions on tongue motor learning

    DEFF Research Database (Denmark)

    Kothari, Mohit; Liu, Xuimei; Baad-Hansen, Lene;

    2016-01-01

    To investigate the impact of visual observational conditions on performance during a standardized tongue-protrusion training (TPT) task and to evaluate subject-based reports of helpfulness, disturbance, pain, and fatigue due to the observational conditions on 0-10 numerical rating scales. Forty...... regarding the level of disturbance, pain or fatigue. Self-observation of tongue-training facilitated behavioral aspects of tongue motor learning compared with model-observation but not compared with control....

  20. Raman spectroscopy detects deterioration in biomechanical properties of bone in a glucocorticoid-treated mouse model of rheumatoid arthritis

    Science.gov (United States)

    Maher, Jason R.; Takahata, Masahiko; Awad, Hani A.; Berger, Andrew J.

    2011-08-01

    Although glucocorticoids are frequently prescribed for the symptomatic management of inflammatory disorders such as rheumatoid arthritis, extended glucocorticoid exposure is the leading cause of physician-induced osteoporosis and leaves patients at a high risk of fracture. To study the biochemical effects of glucocorticoid exposure and how they might affect biomechanical properties of the bone, Raman spectra were acquired from ex vivo tibiae of glucocorticoid- and placebo-treated wild-type mice and a transgenic mouse model of rheumatoid arthritis. Statistically significant spectral differences were observed due to both treatment regimen and mouse genotype. These differences are attributed to changes in the overall bone mineral composition, as well as the degree of phosphate mineralization in tibial cortical bone. In addition, partial least squares regression was used to generate a Raman-based prediction of each tibia's biomechanical strength as quantified by a torsion test. The Raman-based predictions were as accurate as those produced by microcomputed tomography derived parameters, and more accurate than the clinically-used parameter of bone mineral density. These results suggest that Raman spectroscopy could be a valuable tool for monitoring bone biochemistry in studies of bone diseases such as osteoporosis, including tests of drugs being developed to combat these diseases.

  1. Biomechanical effects of titanium implants with full arch bridge rehabilitation on a synthetic model of the human jaw.

    Science.gov (United States)

    De Santis, Roberto; Mollica, Francesco; Zarone, Fernando; Ambrosio, Luigi; Nicolais, Luigi

    2007-01-01

    A composite model of the mandible, constituted by an inner polymeric core and a glass fibre reinforced outer shell, has been developed and equipped with six ITI titanium implants and a full gold alloy arch bridge prosthesis. The effects of this oral rehabilitation on the biomechanics of the mandible are investigated through a simulation of the lateral component of the pterygoid muscles. These muscles are involved as the mouth is opened and closed, hence their activity is very frequent. An increase of the mandible stiffness due to the prosthesis is observed; moreover, the coupling of the relatively stiff rehabilitation devices with the natural tissue analogue leads to stress-shielding and stress-concentration in the incisal and molar regions, respectively. Although the amplitude of the force generated by pterygoid muscles is quite small, high strains over the incisal region are measured. A stress-shielding effect, of about 20%, is observed at the symphysis as the full arch bridge prosthesis is fixed on the implants. Therefore, the presence of the prosthesis leads to significant modification of the stress field experienced by the mandible, and this may be relevant in relation to the biomechanics of mandibular bone remodelling.

  2. Exoskeleton-Based Robotic Platform Applied in Biomechanical Modelling of the Human Upper Limb

    Directory of Open Access Journals (Sweden)

    Andres F. Ruiz

    2009-01-01

    Full Text Available One of the approaches to study the human motor system, and specifically the motor strategies implied during postural tasks of the upper limbs, is to manipulate the mechanical conditions of each joint of the upper limbs independently. At the same time, it is essential to pick up biomechanical signals and bio-potentials generated while the human motor system adapts to the new condition. The aim of this paper is two-fold: first, to describe the design, development and validation of an experimental platform designed to modify or perturb the mechanics of human movement, and simultaneously acquire, process, display and quantify bioelectric and biomechanical signals; second, to characterise the dynamics of the elbow joint during postural control. A main goal of the study was to determine the feasibility of estimating human elbow joint dynamics using EMG-data during maintained posture. In particular, the experimental robotic platform provides data to correlate electromyographic (EMG activity, kinetics and kinematics information from the upper limb motion. The platform aims consists of an upper limb powered exoskeleton, an EMG acquisition module, a control unit and a software system. Important concerns of the platform such as dependability and safety were addressed in the development. The platform was evaluated with 4 subjects to identify, using system identification methods, the human joint dynamics, i.e. visco-elasticity. Results obtained in simulations and experimental phase are introduced.

  3. Increased trabecular bone and improved biomechanics in an osteocalcin-null rat model created by CRISPR/Cas9 technology

    Science.gov (United States)

    Lambert, Laura J.; Challa, Anil K.; Niu, Aidi; Zhou, Lihua; Tucholski, Janusz; Johnson, Maria S.; Nagy, Tim R.; Eberhardt, Alan W.; Estep, Patrick N.; Kesterson, Robert A.

    2016-01-01

    ABSTRACT Osteocalcin, also known as bone γ-carboxyglutamate protein (Bglap), is expressed by osteoblasts and is commonly used as a clinical marker of bone turnover. A mouse model of osteocalcin deficiency has implicated osteocalcin as a mediator of changes to the skeleton, endocrine system, reproductive organs and central nervous system. However, differences between mouse and human osteocalcin at both the genome and protein levels have challenged the validity of extrapolating findings from the osteocalcin-deficient mouse model to human disease. The rat osteocalcin (Bglap) gene locus shares greater synteny with that of humans. To further examine the role of osteocalcin in disease, we created a rat model with complete loss of osteocalcin using the CRISPR/Cas9 system. Rat osteocalcin was modified by injection of CRISPR/Cas9 mRNA into the pronuclei of fertilized single cell Sprague-Dawley embryos, and animals were bred to homozygosity and compound heterozygosity for the mutant alleles. Dual-energy X-ray absorptiometry (DXA), glucose tolerance testing (GTT), insulin tolerance testing (ITT), microcomputed tomography (µCT), and a three-point break biomechanical assay were performed on the excised femurs at 5 months of age. Complete loss of osteocalcin resulted in bones with significantly increased trabecular thickness, density and volume. Cortical bone volume and density were not increased in null animals. The bones had improved functional quality as evidenced by an increase in failure load during the biomechanical stress assay. Differences in glucose homeostasis were observed between groups, but there were no differences in body weight or composition. This rat model of complete loss of osteocalcin provides a platform for further understanding the role of osteocalcin in disease, and it is a novel model of increased bone formation with potential utility in osteoporosis and osteoarthritis research. PMID:27483347

  4. Increased trabecular bone and improved biomechanics in an osteocalcin-null rat model created by CRISPR/Cas9 technology

    Directory of Open Access Journals (Sweden)

    Laura J. Lambert

    2016-10-01

    Full Text Available Osteocalcin, also known as bone γ-carboxyglutamate protein (Bglap, is expressed by osteoblasts and is commonly used as a clinical marker of bone turnover. A mouse model of osteocalcin deficiency has implicated osteocalcin as a mediator of changes to the skeleton, endocrine system, reproductive organs and central nervous system. However, differences between mouse and human osteocalcin at both the genome and protein levels have challenged the validity of extrapolating findings from the osteocalcin-deficient mouse model to human disease. The rat osteocalcin (Bglap gene locus shares greater synteny with that of humans. To further examine the role of osteocalcin in disease, we created a rat model with complete loss of osteocalcin using the CRISPR/Cas9 system. Rat osteocalcin was modified by injection of CRISPR/Cas9 mRNA into the pronuclei of fertilized single cell Sprague-Dawley embryos, and animals were bred to homozygosity and compound heterozygosity for the mutant alleles. Dual-energy X-ray absorptiometry (DXA, glucose tolerance testing (GTT, insulin tolerance testing (ITT, microcomputed tomography (µCT, and a three-point break biomechanical assay were performed on the excised femurs at 5 months of age. Complete loss of osteocalcin resulted in bones with significantly increased trabecular thickness, density and volume. Cortical bone volume and density were not increased in null animals. The bones had improved functional quality as evidenced by an increase in failure load during the biomechanical stress assay. Differences in glucose homeostasis were observed between groups, but there were no differences in body weight or composition. This rat model of complete loss of osteocalcin provides a platform for further understanding the role of osteocalcin in disease, and it is a novel model of increased bone formation with potential utility in osteoporosis and osteoarthritis research.

  5. Biomechanics of Rowing

    Science.gov (United States)

    Hase, Kazunori; Kaya, Motoshi; Yamazaki, Nobutoshi; Andrews, Brian J.; Zavatsky, Amy B.; Halliday, Suzanne E.

    Compared with the other exercise, such as walking and cycling, rowing was expected to have some fitness advantage, while there were some misgivings about the risk of injury. The objectives of this study were to quantify biomechanical characteristics of rowing for fitness and rehabilitation and to offer normative data for the prevention of injury and for determining effective exercise. An experiment was performed to collect the kinematic and kinetic data during rowing by experienced and non-experienced subjects. A three-dimensional whole-body musculo-skeletal model was used to calculate the biomechanical loads, such as the joint moments, the muscular tensions, the joint contact forces and the energy consumption. The results of this study indicate that rowing is an effective exercise for rehabilitation and fitness. However, the non-experienced rower should acquire considerable skill to obtain sufficient exercise. The rowing cadence should be decided according to the purpose of the exercise.

  6. Differences in Age-Related Alterations in Muscle Contraction Properties in Rat Tongue and Hindlimb

    Science.gov (United States)

    Connor, Nadine P.; Ota, Fumikazu; Nagai, Hiromi; Russell, John A.; Leverson, Glen

    2008-01-01

    Purpose: Because of differences in muscle architecture and biomechanics, the purpose of this study was to determine whether muscle contractile properties of rat hindlimb and tongue were differentially affected by aging. Method: Deep peroneal and hypoglossal nerves were stimulated in 6 young and 7 old Fischer 344-Brown Norway rats to allow…

  7. Epidermoid Cyst of Tongue

    Directory of Open Access Journals (Sweden)

    Choubarga Naik

    2016-03-01

    Full Text Available Epidermoid cyst occurring within the tongue is rare. A 5 year old male child was brought to OPD with a tongue mass which was gradually increasing in size. There was associated difficulty in speech and mastication as the swelling increased in size. Intraoral examination revealed moderately tender, fluctuant and enlarged tongue. A diagnosis of dermoid cyst was made and the patient was booked for surgery. Excision of the cyst was done under general anaesthesia. Post-operative histopathology was done. The histopathological findings confirm the diagnosis of an epidermoid cyst, characterized by the presence of: (I a cyst cavity lined by stratified squamous epithelium with keratinization on the surface; and (II connective tissue with a mild inflammation. The proposed treatment was considered successful as the case was solved and there was no recurrence. Keywords: dermoid; epidermoid cyst;tounge. | PubMed

  8. Biomechanical evaluation of predictive parameters of progression in adolescent isthmic spondylolisthesis: a computer modeling and simulation study

    Directory of Open Access Journals (Sweden)

    Sevrain Amandine

    2012-01-01

    Full Text Available Abstract Background Pelvic incidence, sacral slope and slip percentage have been shown to be important predicting factors for assessing the risk of progression of low- and high-grade spondylolisthesis. Biomechanical factors, which affect the stress distribution and the mechanisms involved in the vertebral slippage, may also influence the risk of progression, but they are still not well known. The objective was to biomechanically evaluate how geometric sacral parameters influence shear and normal stress at the lumbosacral junction in spondylolisthesis. Methods A finite element model of a low-grade L5-S1 spondylolisthesis was constructed, including the morphology of the spine, pelvis and rib cage based on measurements from biplanar radiographs of a patient. Variations provided on this model aimed to study the effects on low grade spondylolisthesis as well as reproduce high grade spondylolisthesis. Normal and shear stresses at the lumbosacral junction were analyzed under various pelvic incidences, sacral slopes and slip percentages. Their influence on progression risk was statistically analyzed using a one-way analysis of variance. Results Stresses were mainly concentrated on the growth plate of S1, on the intervertebral disc of L5-S1, and ahead the sacral dome for low grade spondylolisthesis. For high grade spondylolisthesis, more important compression and shear stresses were seen in the anterior part of the growth plate and disc as compared to the lateral and posterior areas. Stress magnitudes over this area increased with slip percentage, sacral slope and pelvic incidence. Strong correlations were found between pelvic incidence and the resulting compression and shear stresses in the growth plate and intervertebral disc at the L5-S1 junction. Conclusions Progression of the slippage is mostly affected by a movement and an increase of stresses at the lumbosacral junction in accordance with spino-pelvic parameters. The statistical results provide

  9. MRI-determined lumbar muscle morphometry in man and sheep: potential biomechanical implications for ovine model to human spine translation.

    Science.gov (United States)

    Valentin, Stephanie; Licka, Theresia F; Elliott, James

    2015-10-01

    The sheep is a commonly used animal model for human lumbar spine surgery, but only in vitro investigations comparing the human and ovine spine exist. Spinal musculature has previously not been compared between man and sheep. This additional knowledge could further indicate to what extent these species are biomechanically similar. Therefore, the purpose of the study was to investigate spinal muscle morphometric properties using magnetic resonance imaging (MRI) in different age groups of healthy human participants and sheep in vivo. Healthy human participants (n = 24) and sheep (n = 17) of different age groups underwent T1-weighted MRI of the lumbar spine. Regions of interest of the muscles erector spinae (ES), multifidus (M) and psoas (PS) were identified. The ratio of flexor to extensor volume, ratio of M to ES volume, and muscle fat relative to an area of intermuscular fat were calculated. Sheep M to ES ratio was significantly smaller than in the human participants (sheep 0.16 ± 0.02; human 0.37 ± 0.05; P sheep 0.43 ± 0.05; P = 0.06). Age did not influence any muscle ratio outcome. Sheep had significantly greater extensor muscle fat compared with the human participants (M left human 40.64%, sheep 53.81%; M right human 39.17%, sheep 51.33%; ES left human 40.86%, sheep 51.29%; ES right human 35.93%, sheep 44.38%; all median values; all P sheep 33.67%; PS right human 32.78%, sheep 30.09%; P sheep and human lumbar spine muscles may indicate dissimilar biomechanical and functional demands, which is an important consideration when translating to human surgical models.

  10. A finite element modeling of posterior atlantoaxial fixation and biomechanical analysis of C2 intralaminar screw fixation

    Institute of Scientific and Technical Information of China (English)

    Ma Xuexiao; Peng Xianbo; Xiang Hongfei; Zhang Yan; Zhang Guoqing; Chen Bohua

    2014-01-01

    Background The objective of this study was to use three-dimensional finite element (FE) models to analyze the stability and the biomechanics of two upper cervical fixation methods:the C2 intralaminar screw method and the C2 pedicle screw method.Methods From computed tomography images,a nonlinear three-dimensional FE model from C0 (occiput) to C3 was developed with anatomic detail.The C2 intralaminar screw and the C2 pedicle screw systems were added to the model,in parallel to establish the interlaminar model and the pedicle model.The two models were operated with all possible states of motion and physiological loads to simulate normal movement.Results Both the C2 intralaminar screw method and the C2 pedicle screw method significantly reduced motion compared with the intact model.There were no statistically significant differences between the two methods.The Von Mises stresses of the internal and external laminar walls were similar between the two methods.Stability was also similar.Conclusions The C2 intralaminar screw method can complement but cannot completely replace the C2 pedicle screw method.Clinicians would need to assess and decide which approach to adopt for the best therapeutic effect.

  11. Radiation response of the mouse tongue epithelium

    Energy Technology Data Exchange (ETDEWEB)

    Moses, R.; Kummermehr, J.

    1986-01-01

    Mouse tongue mucosa has been used as a model to study dose responses to local irradiation. Although the irradiation procedures is less feasible and more time-consuming than e.g. snout irradiation, the tongue is the only location where a reasonable area of intraoral, multilayered epithelium in the mouse can be locally treated and scored, and a relatively small burden is imposed on the animal. In pilot experiments with external 300 kV x-irradiation just tolerated by the lip, the authors did not see critical damage to the tongue. In the present model, the onset of denudation was not correctly predicted by the normal turnover time of the tissue.

  12. Modeling the impact of prostate edema on LDR brachytherapy: a Monte Carlo dosimetry study based on a 3D biphasic finite element biomechanical model

    Science.gov (United States)

    Mountris, K. A.; Bert, J.; Noailly, J.; Rodriguez Aguilera, A.; Valeri, A.; Pradier, O.; Schick, U.; Promayon, E.; Gonzalez Ballester, M. A.; Troccaz, J.; Visvikis, D.

    2017-03-01

    Prostate volume changes due to edema occurrence during transperineal permanent brachytherapy should be taken under consideration to ensure optimal dose delivery. Available edema models, based on prostate volume observations, face several limitations. Therefore, patient-specific models need to be developed to accurately account for the impact of edema. In this study we present a biomechanical model developed to reproduce edema resolution patterns documented in the literature. Using the biphasic mixture theory and finite element analysis, the proposed model takes into consideration the mechanical properties of the pubic area tissues in the evolution of prostate edema. The model’s computed deformations are incorporated in a Monte Carlo simulation to investigate their effect on post-operative dosimetry. The comparison of Day1 and Day30 dosimetry results demonstrates the capability of the proposed model for patient-specific dosimetry improvements, considering the edema dynamics. The proposed model shows excellent ability to reproduce previously described edema resolution patterns and was validated based on previous findings. According to our results, for a prostate volume increase of 10–20% the Day30 urethra D10 dose metric is higher by 4.2%–10.5% compared to the Day1 value. The introduction of the edema dynamics in Day30 dosimetry shows a significant global dose overestimation identified on the conventional static Day30 dosimetry. In conclusion, the proposed edema biomechanical model can improve the treatment planning of transperineal permanent brachytherapy accounting for post-implant dose alterations during the planning procedure.

  13. Development of a Dynamic Biomechanical Model for Load Carriage: Phase III Part C2: Development of a Dynamic Biomechanical Model Version 1 of Human Load Carriage

    Science.gov (United States)

    2005-08-01

    torse ont été définis comme étant des objets sans frottement ayant un coefficient de restitution de 0,5. Tout comme dans le modèle 2D, les sangles...higher damping coefficients to bring about a pack displacement pattern similar to that of the 3D model. In addition, the 3D model behaviour was more...une fréquence naturelle dominante d’environ 5 Hz. Globalement, il a fallu utiliser des coefficients d’amortissement plus élevés avec le modèle 2D

  14. A multi-organ biomechanical model to analyze prostate deformation due to large deformation of the rectum

    Science.gov (United States)

    Brock, Kristy K.; Ménard, Cynthia; Hensel, Jennifer; Jaffray, David A.

    2006-03-01

    Magnetic resonance imaging (MRI) with an endorectal receiver coil (ERC) provides superior visualization of the prostate gland and its surrounding anatomy at the expense of large anatomical deformation. The ability to correct for this deformation is critical to integrate the MR images into the CT-based treatment planning for radiotherapy. The ability to quantify and understand the physiological motion due to large changes in rectal filling can also improve the precision of image-guided procedures. The purpose of this study was to understand the biomechanical relationship between the prostate, rectum, and bladder using a finite element-based multi-organ deformable image registration method, 'Morfeus' developed at our institution. Patients diagnosed with prostate cancer were enrolled in the study. Gold seed markers were implanted in the prostate and MR scans performed with the ERC in place and its surrounding balloon inflated to varying volumes (0-100cc). The prostate, bladder, and rectum were then delineated, converted into finite element models, and assigned appropriate material properties. Morfeus was used to assign surface interfaces between the adjacent organs and deform the bladder and rectum from one position to another, obtaining the position of the prostate through finite element analysis. This approach achieves sub-voxel accuracy of image co-registration in the context of a large ERC deformation, while providing a biomechanical understanding of the multi-organ physiological relationship between the prostate, bladder, and rectum. The development of a deformable registration strategy is essential to integrate the superior information offered in MR images into the treatment planning process.

  15. Rabbit Achilles tendon full transection model – wound healing, adhesion formation and biomechanics at 3, 6 and 12 weeks post-surgery

    Science.gov (United States)

    Meier Bürgisser, Gabriella; Calcagni, Maurizio; Bachmann, Elias; Fessel, Gion; Snedeker, Jess G.; Giovanoli, Pietro

    2016-01-01

    ABSTRACT After tendon rupture repair, two main problems may occur: re-rupture and adhesion formation. Suitable non-murine animal models are needed to study the healing tendon in terms of biomechanical properties and extent of adhesion formation. In this study 24 New Zealand White rabbits received a full transection of the Achilles tendon 2 cm above the calcaneus, sutured with a 4-strand Becker suture. Post-surgical analysis was performed at 3, 6 and 12 weeks. In the 6-week group, animals received a cast either in a 180 deg stretched position during 6 weeks (adhesion provoking immobilization), or were re-casted with a 150 deg position after 3 weeks (adhesion inhibiting immobilization), while in the other groups (3 and 12 weeks) a 180 deg position cast was applied for 3 weeks. Adhesion extent was analyzed by histology and ultrasound. Histopathological scoring was performed according to a method by Stoll et al. (2011), and the main biomechanical properties were assessed. Histopathological scores increased as a function of time, but did not reach values of healthy tendons after 12 weeks (only around 15 out of 20 points). Adhesion provoking immobilization led to an adhesion extent of 82.7±9.7%, while adhesion inhibiting immobilization led to 31.9±9.8% after 6 weeks. Biomechanical properties increased over time, however, they did not reach full strength nor elastic modulus at 12 weeks post-operation. Furthermore, the rabbit Achilles tendon model can be modulated in terms of adhesion formation to the surrounding tissue. It clearly shows the different healing stages in terms of histopathology and offers a suitable model regarding biomechanics because it exhibits similar biomechanics as the human flexor tendons of the hand. PMID:27635037

  16. Artificial cervical vertebra and intervertebral complex replacement through the anterior approach in animal model: a biomechanical and in vivo evaluation of a successful goat model.

    Directory of Open Access Journals (Sweden)

    Jie Qin

    Full Text Available This was an in vitro and in vivo study to develop a novel artificial cervical vertebra and intervertebral complex (ACVC joint in a goat model to provide a new method for treating degenerative disc disease in the cervical spine. The objectives of this study were to test the safety, validity, and effectiveness of ACVC by goat model and to provide preclinical data for a clinical trial in humans in future. We designed the ACVC based on the radiological and anatomical data on goat and human cervical spines, established an animal model by implanting the ACVC into goat cervical spines in vitro prior to in vivo implantation through the anterior approach, and evaluated clinical, radiological, biomechanical parameters after implantation. The X-ray radiological data revealed similarities between goat and human intervertebral angles at the levels of C2-3, C3-4, and C4-5, and between goat and human lordosis angles at the levels of C3-4 and C4-5. In the in vivo implantation, the goats successfully endured the entire experimental procedure and recovered well after the surgery. The radiological results showed that there was no dislocation of the ACVC and that the ACVC successfully restored the intervertebral disc height after the surgery. The biomechanical data showed that there was no significant difference in range of motion (ROM or neural zone (NZ between the control group and the ACVC group in flexion-extension and lateral bending before or after the fatigue test. The ROM and NZ of the ACVC group were greater than those of the control group for rotation. In conclusion, the goat provides an excellent animal model for the biomechanical study of the cervical spine. The ACVC is able to provide instant stability after surgery and to preserve normal motion in the cervical spine.

  17. Tongue schwannoma: clinicopathological findings.

    Science.gov (United States)

    Catalfamo, Luciano; Lombardo, Giuseppe; Nava, Carla; Familiari, Elena; Petrocelli, Marzia; Iudicello, Valeria; Ieni, Antonio; Barresi, Valeria; De Ponte, Francesco Saverio

    2011-05-01

    Schwannomas are peripheral nerve sheath tumors. Approximately 25% of extracranial schwannomas are located in the head and neck district, but only 1% shows an intraoral origin. We report a case of a 28-year-old patient with a tongue schwannoma. Morphologic analysis and immunohistochemical findings strongly support the diagnosis. Surgical treatment is discussed.

  18. Schwannoma of tongue.

    Science.gov (United States)

    Moreno-García, Carlos; Pons-García, María Asunción; González-García, Raúl; Monje-Gil, Florencio

    2014-06-01

    The schwannomas are nervous tissue tumors. We report a case of schwannoma of oral tongue. Because schwannomas are quite rare in the oral cavity, they are often not immediately included in the differential diagnosis of oropharyngeal masses, causing delay in identification and treatment. The definitive diagnosis requires histopathologic examination.

  19. A novel theoretical framework for the dynamic stability analysis, movement control, and trajectory generation in a multisegment biomechanical model.

    Science.gov (United States)

    Iqbal, Kamran; Roy, Anindo

    2009-01-01

    We consider a simplified characterization of the postural control system that embraces two broad components: one representing the musculoskeletal dynamics in the sagittal plane and the other representing proprioceptive feedback and the central nervous system (CNS). Specifically, a planar four-segment neuromusculoskeletal model consisting of the ankle, knee, and hip degrees-of-freedom (DOFs) is described in this paper. The model includes important physiological constructs such as Hill-type muscle model, active and passive muscle stiffnesses, force feedback from the Golgi tendon organ, muscle length and rate feedback from the muscle spindle, and transmission latencies in the neural pathways. A proportional-integral-derivative (PID) controller for each individual DOF is assumed to represent the CNS analog in the modeling paradigm. Our main hypothesis states that all stabilizing PID controllers for such multisegment biomechanical models can be parametrized and analytically synthesized. Our analytical and simulation results show that the proposed representation adequately shapes a postural control that (a) possesses good disturbance rejection and trajectory tracking, (b) is robust against feedback latencies and torque perturbations, and (c) is flexible to embrace changes in the musculoskeletal parameters. We additionally present detailed sensitivity analysis to show that control under conditions of limited or no proprioceptive feedback results in (a) significant reduction in the stability margins, (b) substantial decrease in the available stabilizing parameter set, and (c) oscillatory movement trajectories. Overall, these results suggest that anatomical arrangement, active muscle stiffness, force feedback, and physiological latencies play a major role in shaping motor control processes in humans.

  20. 4th International Plant Biomechanics Conference Proceedings (Abstracts)

    Energy Technology Data Exchange (ETDEWEB)

    Frank W. Telewski; Lothar H. Koehler; Frank W. Ewers

    2003-07-20

    The 4th International Plant Biomechanics Conference facilitated an interdisciplinary exchange between scientists, engineers, and educators addressing the major questions encountered in the field of Plant Biomechanics. Subjects covered by the conference include: Evolution; Ecology; Mechanoreception; Cell Walls; Genetic Modification; Applied Biomechanics of Whole Plants, Plant Products, Fibers & Composites; Fluid Dynamics; Wood & Trees; Fracture Mechanics; Xylem Pressure & Water Transport; Modeling; and Introducing Plant Biomechanics in Secondary School Education.

  1. Phonological Encoding in Mandarin Chinese: Evidence from Tongue Twisters.

    Science.gov (United States)

    Kember, Heather; Croot, Karen; Patrick, Ellis

    2015-12-01

    Models of connected speech production in Mandarin Chinese must specify how lexical tone, speech segments, and phrase-level prosody are integrated in speech production. This study used tongue twisters to test predictions of the two different models of word form encoding. Tongue twisters were constructed from 5 sets of characters that rotated pairs of initial segments or pairs of tones, or both, across format (ABAB, ABBA), and across position of the characters in four-character tongue twister strings. Fifty two native Mandarin Chinese speakers read aloud 120 tongue twisters, repeating each one six times in a row. They made a total of 3503 (2.34%) segment errors and 1372 (.92%) tone errors. Segment errors occurred on the onsets of the first and third characters in the ABBA but not ABAB segment-alternating tongue twisters, and on the onsets of the second and fourth characters of the tone-alternating tongue twisters. Tone errors were highest on the third and fourth characters in the tone-alternating tongue twisters. The pattern of tone errors is consistent with the claim that tone is associated to a metrical frame prior to segment encoding, while the format by position interaction found for the segment-alternating tongue twisters suggest articulatory gestures oscillate in segment production as proposed by gestural phonology.

  2. Biomechanics in Schools.

    Science.gov (United States)

    Vincent, J. F. V.

    1980-01-01

    Examines current usage of the term "biomechanics" and emphasizes the importance of differentiating between structure and material. Describes current prolects in biomechanics and lists four points about the educational significance of the field. (GS)

  3. Research Techniques in Biomechanics.

    Science.gov (United States)

    Ward, Terry

    Biomechanics involves the biological human beings interacting with his/her mechanical environment. Biomechanics research is being done in connection with sport, physical education, and general motor behavior, and concerns mechanics independent of implements. Biomechanics research falls in the following two general categories: (1) that specific…

  4. The molecular features of tongue epithelium treated with the carcinogen 4-nitroquinoline-1-oxide and alcohol as a model for HNSCC.

    Science.gov (United States)

    Osei-Sarfo, Kwame; Tang, Xiao-Han; Urvalek, Alison M; Scognamiglio, Theresa; Gudas, Lorraine J

    2013-11-01

    Head and neck squamous cell carcinoma (HNSCC) is the sixth most common type of cancer affecting humans worldwide. To determine the potential mechanisms by which chronic tobacco and alcohol abuse lead to HNSCC of the oral cavity, we have used both the 4-nitroquinoline-1-oxide (4-NQO) murine oral carcinogenesis and the Meadows-Cook alcohol models. In this study, we treated mice with 4-NQO in drinking water for 10 weeks and then administered 20% (w:v) ethanol (EtOH) for another 10 weeks. We observed increased levels and/or activation of signaling proteins [p38 mitogen-activated protein kinase (MAPK), β-catenin and Erk 1/2] that are typically altered during HNSCC initiation in humans. We found that EtOH administration alone increased the expression of p38 MAPK but not Erk 1/2 MAPK. Total β-catenin levels in the tongues increased by 2- to 3-fold after 4-NQO treatment, with or without EtOH. However, EtOH combined with 4-NQO reduced phosphorylated β-catenin levels, whereas 4-NQO treatment alone did not. These data implicate EtOH as a regulator of β-catenin signaling in this HNSCC model. We also utilized K14-CreER(TAM); ROSA26 mice to mark permanently stem/progenitor cells in the tongue epithelia. We found that 4-NQO alone and 4-NQO plus EtOH treatment resulted in massive, horizontal expansion of stem/progenitor cell populations arising from single stem cells in the basal layer of the epithelia. This expansion is consistent with carcinogen-associated, symmetric division of stem/progenitor cells. Our data suggest that specific therapeutic targets for prevention of HNSCC of the oral cavity associated with both alcohol and tobacco use are p38 MAPK and β-catenin.

  5. The effect of parameters of equilibrium-based 3-D biomechanical models on extracted muscle synergies during isometric lumbar exertion.

    Science.gov (United States)

    Eskandari, A H; Sedaghat-Nejad, E; Rashedi, E; Sedighi, A; Arjmand, N; Parnianpour, M

    2016-04-11

    A hallmark of more advanced models is their higher details of trunk muscles represented by a larger number of muscles. The question is if in reality we control these muscles individually as independent agents or we control groups of them called "synergy". To address this, we employed a 3-D biomechanical model of the spine with 18 trunk muscles that satisfied equilibrium conditions at L4/5, with different cost functions. The solutions of several 2-D and 3-D tasks were arranged in a data matrix and the synergies were computed by using non-negative matrix factorization (NMF) algorithms. Variance accounted for (VAF) was used to evaluate the number of synergies that emerged by the analysis, which were used to reconstruct the original muscle activations. It was showed that four and six muscle synergies were adequate to reconstruct the input data of 2-D and 3-D torque space analysis. The synergies were different by choosing alternative cost functions as expected. The constraints affected the extracted muscle synergies, particularly muscles that participated in more than one functional tasks were influenced substantially. The compositions of extracted muscle synergies were in agreement with experimental studies on healthy participants. The following computational methods show that the synergies can reduce the complexity of load distributions and allow reduced dimensional space to be used in clinical settings.

  6. "Hidden" tongue jewellery.

    LENUS (Irish Health Repository)

    McNamara, C M

    2001-06-01

    Tongue piercing has many associated risks. This is a case report of a patient who, to avoid parental disapproval, hid the dorsal aspect of a lingual stud device. Subsequently, the dorsum repaired. The device could no longer be removed manually and warranted surgical removal. Despite being in situ for over two years, no further complications arose, but all efforts to obtain patient agreement for removal of the device failed.

  7. Fruit biomechanics based on anatomy: a review

    Science.gov (United States)

    Li, Zhiguo; Yang, Hongling; Li, Pingping; Liu, Jizhan; Wang, Jizhang; Xu, Yunfeng

    2013-01-01

    Fruit biomechanics is needed for quality determination, multiscale modelling and engineering design of fruit processes and equipments. However, these determined fruit biomechanics data often have obvious differences for the same fruit or tissue. In order to investigate it, the fruit biomechanics based on anatomy was reviewed in this paper. First, the anatomical characteristics of fruit biomaterials were described at the macroscopic `tissue' level and microscopic `cellular' level. Subsequently, the factors affecting fruit biomechanics based on anatomy and the relationships between fruit biomechanics, texture and mechanical damage were summarised according to the published literature. Fruit biomechanics is mainly affected by size, number and arrangement of cells, quantity and volume of intracellular spaces, structure, thickness, chemical composition and permeability of cell walls, and pectin degradation level and turgor pressure within cells based on microanatomy. Four test methods and partial determined results of fruit biomechanics were listed and reviewed. The determined mechanical properties data of fruit are only approximate values by using the existing four test methods, owing to the fruit biomaterials being non-homogeneous and living. Lastly, further aspects for research on fruit biomechanics were proposed for the future.

  8. Black hairy tongue syndrome.

    Science.gov (United States)

    Gurvits, Grigoriy E; Tan, Amy

    2014-08-21

    Black hairy tongue (BHT) is a benign medical condition characterized by elongated filiform lingual papillae with typical carpet-like appearance of the dorsum of the tongue. Its prevalence varies geographically, typically ranging from 0.6% to 11.3%. Known predisposing factors include smoking, excessive coffee/black tea consumption, poor oral hygiene, trigeminal neuralgia, general debilitation, xerostomia, and medication use. Clinical presentation varies but is typically asymptomatic, although aesthetic concerns are common. Differential diagnosis includes pseudo-BHT, acanthosis nigricans, oral hairy leukoplakia, pigmented fungiform papillae of the tongue, and congenital melanocytic/melanotic nevi/macules. Clinical diagnosis relies on visual observation, detailed history taking, and occasionally microscopic evaluation. Treatment involves identification and discontinuation of the offending agent, modifications of chronic predisposing factors, patient's re-assurance to the benign nature of the condition, and maintenance of adequate oral hygiene with gentle debridement to promote desquamation. Complications of BHT (burning mouth syndrome, halitosis, nausea, gagging, dysgeusia) typically respond to therapy. Prognosis is excellent with treatment of underlying medical conditions. BHT remains an important medical condition which may result in additional burden on the patient and health care system and requires appropriate prevention, recognition and treatment.

  9. Outrun or Outmaneuver: Predator–Prey Interactions as a Model System for Integrating Biomechanical Studies in a Broader Ecological and Evolutionary Context

    OpenAIRE

    Biewener, Andrew Austin; Moore, Talia Yuki

    2015-01-01

    Behavioral studies performed in natural habitats provide a context for the development of hypotheses and the design of experiments relevant both to biomechanics and to evolution. In particular, predator–prey interactions are a model system for integrative study because success or failure of predation has a direct effect on fitness and drives the evolution of specialized performance in both predator and prey. Although all predators share the goal of capturing prey, and all prey share the goal ...

  10. Biomechanics of an orthosis-managed cranial cruciate ligament-deficient canine stifle joint predicted by use of a computer model.

    Science.gov (United States)

    Bertocci, Gina E; Brown, Nathan P; Mich, Patrice M

    2017-01-01

    OBJECTIVE To evaluate effects of an orthosis on biomechanics of a cranial cruciate ligament (CrCL)-deficient canine stifle joint by use of a 3-D quasistatic rigid-body pelvic limb computer model simulating the stance phase of gait and to investigate influences of orthosis hinge stiffness (durometer). SAMPLE A previously developed computer simulation model for a healthy 33-kg 5-year-old neutered Golden Retriever. PROCEDURES A custom stifle joint orthosis was implemented in the CrCL-deficient pelvic limb computer simulation model. Ligament loads, relative tibial translation, and relative tibial rotation in the orthosis-stabilized stifle joint (baseline scenario; high-durometer hinge]) were determined and compared with values for CrCL-intact and CrCL-deficient stifle joints. Sensitivity analysis was conducted to evaluate the influence of orthosis hinge stiffness on model outcome measures. RESULTS The orthosis decreased loads placed on the caudal cruciate and lateral collateral ligaments and increased load placed on the medial collateral ligament, compared with loads for the CrCL-intact stifle joint. Ligament loads were decreased in the orthosis-managed CrCL-deficient stifle joint, compared with loads for the CrCL-deficient stifle joint. Relative tibial translation and rotation decreased but were not eliminated after orthosis management. Increased orthosis hinge stiffness reduced tibial translation and rotation, whereas decreased hinge stiffness increased internal tibial rotation, compared with values for the baseline scenario. CONCLUSIONS AND CLINICAL RELEVANCE Stifle joint biomechanics were improved following orthosis implementation, compared with biomechanics of the CrCL-deficient stifle joint. Orthosis hinge stiffness influenced stifle joint biomechanics. An orthosis may be a viable option to stabilize a CrCL-deficient canine stifle joint.

  11. A porohyperelastic finite element model of the eye: the influence of stiffness and permeability on intraocular pressure and optic nerve head biomechanics.

    Science.gov (United States)

    Ayyalasomayajula, Avinash; Park, Robert I; Simon, Bruce R; Vande Geest, Jonathan P

    2016-01-01

    Progressively deteriorating visual field is a characteristic feature of primary open-angle glaucoma (POAG), and the biomechanics of optic nerve head (ONH) is believed to be important in its onset. We used porohyperelasticity to model the complex porous behavior of ocular tissues to better understand the effect variations in ocular material properties can have on ONH biomechanics. An axisymmetric model of the human eye was constructed to parametrically study how changes in the permeabilities of retina-Bruch's-choroid complex (k(RBC)), sclera k(sclera), uveoscleral pathway (k(UVSC)) and trabecular meshwork k(TM) as well as how changes in the stiffness of the lamina cribrosa (LC) and sclera affect IOP, LC strains, and translaminar interstitial pressure gradients (TLIPG). Decreasing k(RBC) from 5 × 10(- 12) to 5 × 10(- 13) m/s increased IOP and LC strains by 17%, and TLIPG by 21%. LC strains increased by 13% and 9% when the scleral and LC moduli were decreased by 48% and 50%, respectively. In addition to the trabecular meshwork and uveoscleral pathway, the retina-Bruch's-choroid complex had an important effect on IOP, LC strains, and TLIPG. Changes in k(RBC) and scleral modulus resulted in nonlinear changes in the IOP, and LC strains especially at the lowest k(TM) and k(UVSC). This study demonstrates that porohyperelastic modeling provides a novel method for computationally studying the biomechanical environment of the ONH. Porohyperelastic simulations of ocular tissues may help provide further insight into the complex biomechanical environment of posterior ocular tissues in POAG.

  12. Biomechanics Analysis of Pressure Ulcer Using Damaged Interface Model between Bone and Muscle in the Human Buttock

    Science.gov (United States)

    Slamet, Samuel Susanto; Takano, Naoki; Tanabe, Yoshiyuki; Hatano, Asako; Nagasao, Tomohisa

    This paper aims at building up a computational procedure to study the bio-mechanism of pressure ulcer using the finite element method. Pressure ulcer is a disease that occurs in the human body after 2 hours of continuous external force. In the very early stage of pressure ulcer, it is found that the tissues inside the body are damaged, even though skin surface looks normal. This study assumes that tension and/or shear strain will cause damage to loose fibril tissue between the bone and muscle and that propagation of damaged area will lead to fatal stage. Analysis was performed using the finite element method by modeling the damaged fibril tissue as a cutout. By varying the loading directions and watching both tensile and shear strains, the risk of fibril tissue damage and propagation of the damaged area is discussed, which may give new insight for the careful nursing for patients, particularly after surgical treatment. It was found that the pressure ulcer could reoccur for a surgical flap treatment. The bone cut and surgical flap surgery is not perfect to prevent the bone-muscle interfacial damage.

  13. Biomechanical and radiographic comparison of demineralized bone matrix, and a coralline hydroxyapatite in a rabbit spinal fusion model.

    Science.gov (United States)

    Dodds, Robert A; York-Ely, Amanda M; Zhukauskas, Rasa; Arola, Travis; Howell, John; Hartill, Caroline; Cobb, Ronald R; Fox, Casey

    2010-09-01

    The use of bone grafts is an essential component in spinal fusion. Autologous bone has been shown to result in long-term stable arthrodesis between spinal motion segments. However, autograft can be associated with significant morbidity and a limited supply. Alternatives, such as allogeneic demineralized bone matrix (DBM), are a potential source and supplement to autograft bone. The current study compares the ability of a DBM product (BioSet RT) and a coralline hydroxyapatite (Pro Osteon 500R), for inducing spinal fusion in a rabbit model. BioSet RT, alone or in combination with autograft, and Pro Osteon 500R were implanted in the posterior lateral inter-transverse process region of the rabbit spine. The spines were evaluated at 18 weeks for fusion of the L4-L5 transverse processes using a total of 33 skeletally mature male rabbits; 4 naïve animals were also included in the study. Samples were evaluated radiographically, histologically, by palpation, and through mechanical strength testing. Radiographical, histological, and palpation measurements demonstrated the ability of BioSet RT to induce new bone formation and bridging fusion comparable to autograft. This material performed well alone or in combination with autograft material. Despite significantly higher biomechanical testing results, minimal bone formation and fusion was recorded for the Pro Osteon 500R-treated group. This in vivo study demonstrates the ability of BioSet RT to induce new bone formation, and there was a clear relationship between bridging bone and mechanical strength.

  14. Proximal humeral fractures: a biomechanical comparison of locking plate constructs in a cadaveric 3-part fracture model.

    Science.gov (United States)

    Rose, David M; Sutter, Edward G; Mears, Simon C; Gupta, Rohit R; Belkoff, Stephen M

    2010-11-01

    The purpose of our study was to biomechanically compare, under cyclic loading conditions, fracture site motion, humeral head collapse, and intra-articular hardware penetration in simulated 3-part osteoporotic proximal humeral fractures stabilized with 1 of 2 locking-plate constructs. We performed fixation on simulated 3-part proximal humeral fractures in 10 pairs of cadaveric osteoporotic humeri with a Hand Innovations S3 Proximal Humerus Plate (S3 plate) or an LCP Proximal Humerus Plate (LCP plate; 1 each for each pair). The specimens were potted, mounted on a materials testing machine, and subjected to 5000 cycles of abduction in the scapular plane, loading through the supraspinatus tendon. Interfragmentary displacement at 2 virtual points (the most medial aspect of the calcar and the most superior aspect of the osteotomy line between the greater tuberosity and humeral head) was measured using an optical tracking system. Humeral head rotation was also measured. We used a generalized linear latent and mixed model to check for an effect of cyclic loading and treatment on the parameters of interest (significance, P fracture site motion, it is unknown whether the magnitude of the motion is clinically significant.

  15. Contact hypersensitivity after tongue piercing

    Directory of Open Access Journals (Sweden)

    Ananta Herachakri P

    2010-09-01

    Full Text Available Background: Recently tongue piercing has become increasingly popular in the society. Several case reports have presented various complications of tongue piercing. However, there is no scientific evidence about contact hypersensitivity to tongue piercing. Purpose: The aim of this study was to investigate the contact hypersensitivity after using tongue piercing. Methods: Nineteen male Rattus norvegicus were divided into three groups: group A treated with vaseline on the back and dorsum tongue (control group, group B (I treated with HgCl2 10% cream on the tongue dorsum, group B (II treated with tongue piercing for 10 days and group C with HgCl 2 10% cream on the back, ear lobe, and tongue, then re-exposure with same materials on ear, back and tongue for 24 and 48 hours. Before and after 24 and 48 hours applications, ear width was measured with sliding caliper. At the end of treatments, the rats were sacrificed. All tissue specimens were made for Hematoylin Eosine (H&E staining examination. The number of mononuclear cells was counted under light microscope Data was analyzed with One-Way ANOVA followed by LSD (p<0.05. Results: The result of this study showed that there were a significant difference of the thickness of ear lobe and the number of mononuclear cells (lymphocyte and monocyte among all groups. Conclusion: It is concluded that tongue piercing induce contact hypersensitivity.Latar belakang: Saat ini pemakaian tongue piercing sangat popular di masyarakat. Beberapa laporan kasus menunjukkan bahwa tongue piercing menimbulkan beberapa komplikasi. Namun, belum ada bukti ilmiah mengenai reaksi hipesensitivitas tongue piercing. Tujuan: Untuk mengetahui reaksi hipersensitivitas setelah menggunakan tongue piercing. Metode: Sembilan belas tikus jantan Rattus novergicus yang dibagi dalam tiga kemlompok yaitu: grup A diberi perlakuan dengan vaselin pada punggung dan dorsum lidah, grup B (I diberi perlakuan dengan krim HgCl2 10% pada dorsum lidah dan B

  16. Effect of ovariectomy on BMD, micro-architecture and biomechanics of cortical and cancellous bones in a sheep model.

    Science.gov (United States)

    Wu, Zi-xiang; Lei, Wei; Hu, Yun-yu; Wang, Hai-qiang; Wan, Shi-yong; Ma, Zhen-sheng; Sang, Hong-xun; Fu, Suo-chao; Han, Yi-sheng

    2008-11-01

    Osteoporotic/osteopenia fractures occur most frequently in trabeculae-rich skeletal sites. The purpose of this study was to use a high-resolution micro-computed tomography (micro-CT) and dual energy X-ray absorptionmeter (DEXA) to investigate the changes in micro-architecture and bone mineral density (BMD) in a sheep model resulted from ovariectomy (OVX). Biomechanical tests were performed to evaluate the strength of the trabecular bone. Twenty adult sheeps were randomly divided into three groups: sham group (n=8), group 1 (n=4) and group 2 (n=8). In groups 1 and 2, all sheep were ovariectomized (OVX); in the sham group, the ovaries were located and the oviducts were ligated. In all animals, BMD for lumbar spine was obtained during the surgical procedure. BMD at the spine, femoral neck and femoral condyle was determined 6 months (group 1) and 12 months (group 2) post-OVX. Lumbar spines and femora were obtained and underwent BMD scan, micro-CT analysis. Compressive mechanical properties were determined from biopsies of vertebral bodies and femoral condyles. BMD, micro-architectural parameters and mechanical properties of cancellous bone did not decrease significantly at 6 months post-OVX. Twelve months after OVX, BMD, micro-architectural parameters and mechanical properties decreased significantly. The results of linear regression analyses showed that trabecular thickness (Tb.Th) (r=0.945, R2=0.886) and bone volume fraction (BV/TV) (r=0.783, R2=0.586) had strong (R2>0.5) correlation to compression stress. In OVX sheep, changes in the structural parameters of trabecular bone are comparable to the human situation during osteoporosis was induced. The sheep model presented seems to meet the criteria for an osteopenia model for fracture treatment with respect to morphometric and mechanical properties. But the duration of OVX must be longer than 12 months to ensure the animal model can be established successfully.

  17. The biomechanics of a validated finite element model of stress shielding in a novel hybrid total knee replacement.

    Science.gov (United States)

    Bougherara, H; Zdero, R; Mahboob, Z; Dubov, A; Shah, S; Schemitsch, E H

    2010-10-01

    This study proposes a novel hybrid total knee replacement (TKR) design to improve stress transfer to bone in the distal femur and, thereby, reduce stress shielding and consequent bone loss. Three-dimensional finite element (FE) models were developed for a standard and a hybrid TKR and validated experimentally. The Duracon knee system (Stryker Canada) was the standard TKR used for the FE models and for the experimental tests. The FE hybrid device was identical to the standard TKR, except that it had an interposing layer of carbon fibre-reinforced polyamide 12 lining the back of the metallic femoral component. A series of experimental surface strain measurements were then taken to validate the FE model of the standard TKR at 3000 N of axial compression and at 0 degreeof knee flexion. Comparison of surface strain values from FE analysis with experiments demonstrated good agreement, yielding a high Pearson correlation coefficient of R(2)= 0.94. Under a 3000N axial load and knee flexion angles simulating full stance (0O degree, heel strike (200 degrees, and toe off (600 degrees during normal walking gait, the FE model showed considerable changes in maximum Von Mises stress in the region most susceptible to stress shielding (i.e. the anterior region, just behind the flange of the femoral implant). Specifically, going from a standard to a hybrid TKR caused an increase in maximum stress of 87.4 per cent (O0 degree from 0.15 to 0.28 MPa), 68.3 per cent (200 degrees from 1.02 to 1.71 MPa), and 12.6 per cent (600 degrees from 2.96 to 3.33 MPa). This can potentially decrease stress shielding and subsequent bone loss and knee implant loosening. This is the first report to propose and biomechanically to assess a novel hybrid TKR design that uses a layer of carbon fibrereinforced polyamide 12 to reduce stress shielding.

  18. FUNDAMENTALS OF BIOMECHANICS

    Directory of Open Access Journals (Sweden)

    Duane Knudson

    2007-09-01

    Full Text Available DESCRIPTION This book provides a broad and in-depth theoretical and practical description of the fundamental concepts in understanding biomechanics in the qualitative analysis of human movement. PURPOSE The aim is to bring together up-to-date biomechanical knowledge with expert application knowledge. Extensive referencing for students is also provided. FEATURES This textbook is divided into 12 chapters within four parts, including a lab activities section at the end. The division is as follows: Part 1 Introduction: 1.Introduction to biomechanics of human movement; 2.Fundamentals of biomechanics and qualitative analysis; Part 2 Biological/Structural Bases: 3.Anatomical description and its limitations; 4.Mechanics of the musculoskeletal system; Part 3 Mechanical Bases: 5.Linear and angular kinematics; 6.Linear kinetics; 7.Angular kinetics; 8.Fluid mechanics; Part 4 Application of Biomechanics in Qualitative Analysis :9.Applying biomechanics in physical education; 10.Applying biomechanics in coaching; 11.Applying biomechanics in strength and conditioning; 12.Applying biomechanics in sports medicine and rehabilitation. AUDIENCE This is an important reading for both student and educators in the medicine, sport and exercise-related fields. For the researcher and lecturer it would be a helpful guide to plan and prepare more detailed experimental designs or lecture and/or laboratory classes in exercise and sport biomechanics. ASSESSMENT The text provides a constructive fundamental resource for biomechanics, exercise and sport-related students, teachers and researchers as well as anyone interested in understanding motion. It is also very useful since being clearly written and presenting several ways of examples of the application of biomechanics to help teach and apply biomechanical variables and concepts, including sport-related ones

  19. Patellofemoral anatomy and biomechanics.

    Science.gov (United States)

    Sherman, Seth L; Plackis, Andreas C; Nuelle, Clayton W

    2014-07-01

    Patellofemoral disorders are common. There is a broad spectrum of disease, ranging from patellofemoral pain and instability to focal cartilage disease and arthritis. Regardless of the specific condition, abnormal anatomy and biomechanics are often the root cause of patellofemoral dysfunction. A thorough understanding of normal patellofemoral anatomy and biomechanics is critical for the treating physician. Recognizing and addressing abnormal anatomy will optimize patellofemoral biomechanics and may ultimately translate into clinical success.

  20. Biomechanics principles and practices

    CERN Document Server

    Peterson, Donald R

    2014-01-01

    Presents Current Principles and ApplicationsBiomedical engineering is considered to be the most expansive of all the engineering sciences. Its function involves the direct combination of core engineering sciences as well as knowledge of nonengineering disciplines such as biology and medicine. Drawing on material from the biomechanics section of The Biomedical Engineering Handbook, Fourth Edition and utilizing the expert knowledge of respected published scientists in the application and research of biomechanics, Biomechanics: Principles and Practices discusses the latest principles and applicat

  1. Experimental identification of the lateral human-structure interaction mechanism and assessment of the inverted-pendulum biomechanical model

    Science.gov (United States)

    Carroll, S. P.; Owen, J. S.; Hussein, M. F. M.

    2014-10-01

    simplicity of this biomechanical model, remarkable agreement was observed.

  2. Safety of children in cars: A review of biomechanical aspects and human body models

    Directory of Open Access Journals (Sweden)

    Karin Brolin

    2015-03-01

    To study how children interact with restraints during on-road driving and during pre- and in-crash events, numerical child models implementing age-specific anthropometric features will be essential. The review of human whole body models covers multi body models (age 1.5 to 15 years and finite element models (ages 3, 6, and 10 years. All reviewed child models are developed for crash scenarios. The only finite element models to implement age dependent anthropometry details for the spine and pelvis were a 3 year-old model and an upcoming 10 year-old model. One ongoing project is implementing active muscles response in a 6 year-old multi body model to study pre-crash scenarios. These active models are suitable for the next important step in providing the automotive industry with adequate tools for development and assessment of future restraint systems in the full sequence of events from pre- to in-crash.

  3. Upper extremity biomechanical model for evaluation of pediatric joint demands during wheelchair mobility.

    Science.gov (United States)

    Paul, Alyssa J; Slavens, Brooke A; Graf, Adam; Krzak, Joseph; Vogel, Lawrence; Harris, Gerald F

    2012-01-01

    Current methods for evaluating upper extremity (UE) dynamics during pediatric wheelchair use are limited. We propose a new model to characterize UE joint kinematics and kinetics during pediatric wheelchair mobility. The bilateral model is comprised of the thorax, clavicle, scapula, upper arm, forearm, and hand segments. The modeled joints include: sternoclavicular, acromioclavicular, glenohumeral, elbow and wrist. The model is complete and is currently undergoing pilot studies for clinical application. Results may provide considerable quantitative insight into pediatric UE joint dynamics to improve wheelchair prescription, training and long term care of children with orthopaedic disabilities.

  4. A Biomechanical Model of the Scapulothoracic Joint to Accurately Capture Scapular Kinematics during Shoulder Movements.

    Science.gov (United States)

    Seth, Ajay; Matias, Ricardo; Veloso, António P; Delp, Scott L

    2016-01-01

    The complexity of shoulder mechanics combined with the movement of skin relative to the scapula makes it difficult to measure shoulder kinematics with sufficient accuracy to distinguish between symptomatic and asymptomatic individuals. Multibody skeletal models can improve motion capture accuracy by reducing the space of possible joint movements, and models are used widely to improve measurement of lower limb kinematics. In this study, we developed a rigid-body model of a scapulothoracic joint to describe the kinematics of the scapula relative to the thorax. This model describes scapular kinematics with four degrees of freedom: 1) elevation and 2) abduction of the scapula on an ellipsoidal thoracic surface, 3) upward rotation of the scapula normal to the thoracic surface, and 4) internal rotation of the scapula to lift the medial border of the scapula off the surface of the thorax. The surface dimensions and joint axes can be customized to match an individual's anthropometry. We compared the model to "gold standard" bone-pin kinematics collected during three shoulder tasks and found modeled scapular kinematics to be accurate to within 2 mm root-mean-squared error for individual bone-pin markers across all markers and movement tasks. As an additional test, we added random and systematic noise to the bone-pin marker data and found that the model reduced kinematic variability due to noise by 65% compared to Euler angles computed without the model. Our scapulothoracic joint model can be used for inverse and forward dynamics analyses and to compute joint reaction loads. The computational performance of the scapulothoracic joint model is well suited for real-time applications; it is freely available for use with OpenSim 3.2, and is customizable and usable with other OpenSim models.

  5. A Biomechanical Model of the Scapulothoracic Joint to Accurately Capture Scapular Kinematics during Shoulder Movements.

    Directory of Open Access Journals (Sweden)

    Ajay Seth

    Full Text Available The complexity of shoulder mechanics combined with the movement of skin relative to the scapula makes it difficult to measure shoulder kinematics with sufficient accuracy to distinguish between symptomatic and asymptomatic individuals. Multibody skeletal models can improve motion capture accuracy by reducing the space of possible joint movements, and models are used widely to improve measurement of lower limb kinematics. In this study, we developed a rigid-body model of a scapulothoracic joint to describe the kinematics of the scapula relative to the thorax. This model describes scapular kinematics with four degrees of freedom: 1 elevation and 2 abduction of the scapula on an ellipsoidal thoracic surface, 3 upward rotation of the scapula normal to the thoracic surface, and 4 internal rotation of the scapula to lift the medial border of the scapula off the surface of the thorax. The surface dimensions and joint axes can be customized to match an individual's anthropometry. We compared the model to "gold standard" bone-pin kinematics collected during three shoulder tasks and found modeled scapular kinematics to be accurate to within 2 mm root-mean-squared error for individual bone-pin markers across all markers and movement tasks. As an additional test, we added random and systematic noise to the bone-pin marker data and found that the model reduced kinematic variability due to noise by 65% compared to Euler angles computed without the model. Our scapulothoracic joint model can be used for inverse and forward dynamics analyses and to compute joint reaction loads. The computational performance of the scapulothoracic joint model is well suited for real-time applications; it is freely available for use with OpenSim 3.2, and is customizable and usable with other OpenSim models.

  6. A Functional Model of the Digital Extensor Mechanism: Demonstrating Biomechanics with Hair Bands

    Science.gov (United States)

    Cloud, Beth A.; Youdas, James W.; Hellyer, Nathan J.; Krause, David A.

    2010-01-01

    The action of muscles about joints can be explained through analysis of their spatial relationship. A functional model of these relationships can be valuable in learning and understanding the muscular action about a joint. A model can be particularly helpful when examining complex actions across multiple joints such as in the digital extensor…

  7. The importance of accurate muscle modelling for biomechanical analyses: a case study with a lizard skull

    Science.gov (United States)

    Gröning, Flora; Jones, Marc E. H.; Curtis, Neil; Herrel, Anthony; O'Higgins, Paul; Evans, Susan E.; Fagan, Michael J.

    2013-01-01

    Computer-based simulation techniques such as multi-body dynamics analysis are becoming increasingly popular in the field of skull mechanics. Multi-body models can be used for studying the relationships between skull architecture, muscle morphology and feeding performance. However, to be confident in the modelling results, models need to be validated against experimental data, and the effects of uncertainties or inaccuracies in the chosen model attributes need to be assessed with sensitivity analyses. Here, we compare the bite forces predicted by a multi-body model of a lizard (Tupinambis merianae) with in vivo measurements, using anatomical data collected from the same specimen. This subject-specific model predicts bite forces that are very close to the in vivo measurements and also shows a consistent increase in bite force as the bite position is moved posteriorly on the jaw. However, the model is very sensitive to changes in muscle attributes such as fibre length, intrinsic muscle strength and force orientation, with bite force predictions varying considerably when these three variables are altered. We conclude that accurate muscle measurements are crucial to building realistic multi-body models and that subject-specific data should be used whenever possible. PMID:23614944

  8. Optical techniques as validation tools for finite element modeling of biomechanical structures, demonstrated in bird ear research

    Science.gov (United States)

    Muyshondt, Pieter; De Greef, Daniël; Soons, Joris; Dirckx, Joris J. J.

    2014-05-01

    In this paper we demonstrate the potential of stroboscopic digital holography and laser vibrometry as tools to gather vibration data and validate modelling results in complex biomechanical systems, in this case the avian middle ear. Whereas the middle ear of all mammal species contains three ossicles, birds only feature one ossicle, the columella. Despite this far simpler design, the hearing range of most birds is comparable to mammals, and is adapted to operate under very diverse atmospheric circumstances. This makes the investigation of the avian middle ear potentially very meaningful, since it could provide knowledge that can improve the design of prosthetic ossicle replacements in humans such as a TORP (Total Ossicle Replacement Prosthesis). In order to better understand the mechanics of the bird's hearing, we developed a finite element model that simulates the transmission of an incident acoustic wave on the eardrum via the middle ear structures to the fluid of the inner ear. The model is based on geometry extracted from stained μCT data and is validated using results from stroboscopic digital holography measurements on the eardrum and LDV measurements on the columella footplate. This technique uses very short high-power laser pulses that are synchronized to the membrane's vibration phase to measure the dynamic response of the bird's eardrum to an incident acoustic stimulus. Vibration magnitude as well as phase relative to the sound wave can be deduced from the results, the latter being of great importance in the elastic characterization of the tympanic membrane. In this work, the setup and results from the optical measurements, as well as the properties and optimization of the finite element model are presented. Observed phase variations across the eardrum's surface on the holography results strongly suggest the presence of internal energy losses in the membrane due to damping. Therefore, a viscoelastic characterisation of the model based on a complex

  9. Quantifying Post- Laser Ablation Prostate Therapy Changes on MRI via a Domain-Specific Biomechanical Model: Preliminary Findings.

    Directory of Open Access Journals (Sweden)

    Robert Toth

    Full Text Available Focal laser ablation destroys cancerous cells via thermal destruction of tissue by a laser. Heat is absorbed, causing thermal necrosis of the target region. It combines the aggressive benefits of radiation treatment (destroying cancer cells without the harmful side effects (due to its precise localization. MRI is typically used pre-treatment to determine the targeted area, and post-treatment to determine efficacy by detecting necrotic tissue, or tumor recurrence. However, no system exists to quantitatively evaluate the post-treatment effects on the morphology and structure via MRI. To quantify these changes, the pre- and post-treatment MR images must first be spatially aligned. The goal is to quantify (a laser-induced shape-based changes, and (b changes in MRI parameters post-treatment. The shape-based changes may be correlated with treatment efficacy, and the quantitative effects of laser treatment over time is currently poorly understood. This work attempts to model changes in gland morphology following laser treatment due to (1 patient alignment, (2 changes due to surrounding organs such as the bladder and rectum, and (3 changes due to the treatment itself. To isolate the treatment-induced shape-based changes, the changes from (1 and (2 are first modeled and removed using a finite element model (FEM. A FEM models the physical properties of tissue. The use of a physical biomechanical model is important since a stated goal of this work is to determine the physical shape-based changes to the prostate from the treatment, and therefore only physical real deformations are to be allowed. A second FEM is then used to isolate the physical, shape-based, treatment-induced changes. We applied and evaluated our model in capturing the laser induced changes to the prostate morphology on eight patients with 3.0 Tesla, T2-weighted MRI, acquired approximately six months following treatment. Our results suggest the laser treatment causes a decrease in prostate

  10. Biomechanical analysis of a newly developed shape memory alloy hook in a transforaminal lumbar interbody fusion (TLIF in vitro model.

    Directory of Open Access Journals (Sweden)

    Xi Wang

    Full Text Available The objective of this biomechanical study was to evaluate the stability provided by a newly developed shape memory alloy hook (SMAH in a cadaveric transforaminal lumbar interbody fusion (TLIF model.Six human cadaveric spines (L1-S2 were tested in an in vitro flexibility experiment by applying pure moments of ±8 Nm in flexion/extension, left/right lateral bending, and left/right axial rotation. After intact testing, a TLIF was performed at L4-5. Each specimen was tested for the following constructs: unilateral SMAH (USMAH; bilateral SMAH (BSMAH; unilateral pedicle screws and rods (UPS; and bilateral pedicle screws and rods (BPS. The L3-L4, L4-L5, and L5-S1 range of motion (ROM were recorded by a Motion Analysis System.Compared to the other constructs, the BPS provided the most stability. The UPS significantly reduced the ROM in extension/flexion and lateral bending; the BSMAH significantly reduced the ROM in extension/flexion, lateral bending, and axial rotation; and the USMAH significantly reduced the ROM in flexion and left lateral bending compared with the intact spine (p0.05. Stability provided by the USMAH compared with the UPS was not significantly different. ROMs of adjacent segments increased in all fixed constructs (p>0.05.Bilateral SMAH fixation can achieve immediate stability after L4-5 TLIF in vitro. Further studies are required to determine whether the SMAH can achieve fusion in vivo and alleviate adjacent segment degeneration.

  11. Effects of extracorporeal shockwave therapy on nanostructural and biomechanical responses in the collagenase-induced Achilles tendinitis animal model.

    Science.gov (United States)

    Yoo, Seung Don; Choi, Samjin; Lee, Gi-Ja; Chon, Jinmann; Jeong, Yong Seol; Park, Hun-Kuk; Kim, Hee-Sang

    2012-11-01

    The aim of this study was to quantitatively investigate the effects of extracorporeal shockwave therapy (ESWT) on the nanostructure and adhesion force of collagen fibrils in a rat model of collagenase-induced Achilles tendinitis (CIAT) using histology and atomic force microscopy. A total of 45 rats were divided into experimental groups of three rats each: a control group, 27 CIAT rats with nine time points, and 15 ESWT rats with five time points. Progressive changes in nanostructure including the fibrillary diameter and D-periodicity, and biomechanical properties including the fibrillary adhesion forces in each healing phase were investigated over a 5-week period after collagenase injection. On postoperative day 3, CIAT rats showed granulomatous tissue associated with subacute inflammation, and a deterioration in nanostructure and mechanical properties compared to controls. On postoperative day 12, the ESWT group showed increased vascularity, fibroblastic activity, lymphocyte and plasma cell infiltration, dense histocytes, and disorganization of the fibers compared to the CIAT group. The ESWT group showed and improvement in nanostructure and mechanical properties compared to controls, while the CIAT group showed a deterioration in nanostructure and mechanical properties compared to controls. On postoperative day 26, the ESWT group showed 30% inflamed tissue and 70% fibrotic tissue, while the CIAT group showed chronic inflammation. By the end of the experiments, in both groups the changes had reversed and the tissues were similar in appearance to those in the control group. Following ESWT the deformed and irregular collagen network returned to a well-aligned normal collagen network nanostructure. These results suggest that ESWT may promote the healing response in Achilles tendinitis.

  12. Virtual musculo-skeletal model for the biomechanical analysis of the upper limb.

    Science.gov (United States)

    Pennestrì, E; Stefanelli, R; Valentini, P P; Vita, L

    2007-01-01

    In this paper, a musculo-skeletal model of the upper limb is presented. The limb is modelled as a three-dimensional 7 degrees-of-freedom system, linked to the shoulder, which has been considered as frame. The upper limb model is made up of four links corresponding to the most important body segments: the humerus, the ulna, the radius and the hand, considered as a single rigid body. Particular attention has been paid to the modelling of joints in order to mimic all the possible arm and forearm movements (including prono-supination). The model also includes 24 muscles. The mathematical model used to describe the muscles is that proposed by Zajac in 1989, modified by the authors. The kinematic analysis has been performed including an ergonomics index to take into account the posture and joint physical limits. Moreover an optimization criterion based on minimum activation pattern has been included in order to find muscular activation coefficients. The results of the proposed methodology concerning muscular activations have been compared to those coming from processed EMG signals, which have been acquired during experimental tests.

  13. Establishment of the biomechanical model of cochlea of guinea pig%豚鼠耳蜗生物数值模型的实验研究

    Institute of Scientific and Technical Information of China (English)

    苏英锋; 孙秀珍; 刘迎曦; 闫志勇; 沈双; 辛晓燕; 于申

    2015-01-01

    Objective To establish a macro-biomechanical model of the guinea pig's cochlea.Methods Both cochlea, abstracted from bilateral temporal bones of a healthy adult guinea pig, which was tested firstly including a series of examina-tion including electric otoscopy, acoustic immittance,brainstem auditory evoked potential, otoacoustic emissions, CT scan and so on.And then, a whole set of inner ear tissue slices images was obtained after a series of operations including embed-ding, slicing ( thickness 6μm) , immobilization, coloretur, photographing and so on.The images were processed by Photo-shop software, mimics software and Hypermesh software sequencely and a biomechanical model of the cochlea was obtained with ANSYS13.0 eventually.Based on the model, the modal analysis was done to test the accuracy of the model.Results Spatial structural feature of the reconstructed biomechanical model of the guinea pig's cochlea was displayed typically and the result of the model analysis proceeded on the macro-biomechanical model was the same as traveling wave theory.Con-clusion It is feasible technically to reconstruct biomechanical model of the cochlea with the tissue slices combining with the finite element soft wares.And the macro-biomechanical model could be applied to study the sensing process of cochlea.%目的:建立豚鼠耳蜗宏观生物数值模型。方法取成年豚鼠1只,进行电耳镜、声导抗、听性脑干反应、耳声发射及内耳薄层CT扫描,除外耳部疾患及内耳畸形,全麻断头后取耳蜗,经石蜡包埋、连续切片(6μm)、HE染色、摄像等步骤获得一整套豚鼠内耳组织切片的图像资料;利用Photoshop软件进行去色、调整灰度及对比度等处理,利用mimics软件识别边界并标定,获得边界点的三维坐标,将坐标导入Hypermesh软件建立网格化模型,利用ANASYS软件建立耳蜗膜迷路的三维生物数值模型,基于该模型进行基底膜的模态分析。结

  14. A novel progress of leg tissue properties modeling based on biomechanics

    Institute of Scientific and Technical Information of China (English)

    WANG Mo-nan

    2009-01-01

    To describe strategies for addressing technical aspects of computational modeling of leg tissue with the finite element (FE) method, a patient's leg sample was selected and scanned by CT at the direction parallel to the Frankfort Horizontal plane. A three-dimensional (3D) finite element model of the human leg was developed using the actual geometry of the leg skeleton and soft tissues, which were obtained from 3 D reconstruction of CT images. All joints were defined as contact surfaces, which allow relative articulating movement. The major ligaments were simulated using tension-only truss elements by connecting the corresponding attachment points on the bone surfaces. The bony and ligamentons structures were embedded in a volume of soft tissues.The muscles were defined as non-linear viscoelastic material, and the skin, ligaments and tendons were defined as hyperelastic, while the bony structures were assumed to be Linearly elastic. The muhilayer FEM model conraining thighbone, tibia, fibula, kneecap, soft tissue was formed after meshing. Diverse forces were imposed on the FEM model. The results show that the muhilayer FEM model can represent tissue deformation more accurately.

  15. Prediction of Pneumonia in Acute Stroke Patients Using Tongue Pressure Measurements

    Science.gov (United States)

    Nakamori, Masahiro; Hosomi, Naohisa; Ishikawa, Kenichi; Imamura, Eiji; Shishido, Takeo; Ohshita, Tomohiko; Yoshikawa, Mineka; Tsuga, Kazuhiro; Wakabayashi, Shinichi; Maruyama, Hirofumi; Matsumoto, Masayasu

    2016-01-01

    Swallowing dysfunction caused by stroke is a risk factor for aspiration pneumonia. Tongue pressure measurement is a simple and noninvasive method for evaluating swallowing dysfunction. We have hypothesized that low tongue pressure may be able to predict pneumonia occurrence in acute stroke patients. Tongue pressure was measured using balloon-type equipment in 220 acute stroke patients. The modified Mann Assessment of Swallowing Ability (MASA) score was evaluated independently on the same day. Tongue pressure was measured every week thereafter. An improvement in tongue pressure was observed within the first 2 weeks. Receiver operating curve analysis was performed to determine the ability of tongue pressure to predict modified MASA score <95, which suggests swallowing dysfunction. The optimal cutoff for tongue pressure was 21.6 kPa (χ2 = 45.82, p<0.001, sensitivity 95.9%, specificity 91.8%, area under the curve = 0.97). The tongue pressure was significantly lower in patients with pneumonia than in those without pneumonia. Using a Cox proportional hazard model for pneumonia onset with a cutoff tongue pressure value of 21.6 kPa and adjustment for age, sex, and National Institutes of Health Stroke Scale score at admission, the tongue pressure had additional predictive power for pneumonia onset (hazard ratio, 7.95; 95% confidence interval, 2.09 to 52.11; p = 0.0013). In the group with low tongue pressure, 27 of 95 patients showed improvement of tongue pressure within 2 weeks. Pneumonia occurred frequently in patients without improvement of tongue pressure, but not in patients with improvement (31/68 and 2/27, p<0.001). Tongue pressure is a sensitive indicator for predicting pneumonia occurrence in acute stroke patients. PMID:27802333

  16. The Effect of Tongue Exercise on Serotonergic Input to the Hypoglossal Nucleus in Young and Old Rats

    Science.gov (United States)

    Behan, Mary; Moeser, Adam E.; Thomas, Cathy F.; Russell, John A.; Wang, Hao; Leverson, Glen E.; Connor, Nadine P.

    2012-01-01

    Purpose: Breathing and swallowing problems affect elderly people and may be related to age-associated tongue dysfunction. Hypoglossal motoneurons that innervate the tongue receive a robust, excitatory serotonergic (5HT) input and may be affected by aging. We used a rat model of aging and progressive resistance tongue exercise to determine whether…

  17. Research progress on the human lower limb biomechanical modeling%人体下肢生物力学建模研究进展

    Institute of Scientific and Technical Information of China (English)

    邵明旭; 王斐; 殷腾龙; 刘健

    2015-01-01

    The research on the biomechanical modeling and simulation of human lower limbs is an important content in the development of wearable exoskeleton robots.Theoretical and technical methods derived from this research can promote the process of biomechanics, rehabilitation medicine and prosthetic/orthotic devices.This work reviews the state-of-the-art techniques for modeling and simulating biomechanics of human lower limbs and makes analysis of popular methods, such as multi-body modeling , simulation software modeling, Hill three elements modeling and black box training modeling based on Lagrange equation and theorem of angular momentum.The future prospects in this research field are also provided in this paper.The biomechanical modeling and simulating methods discussed is of great significance to the design of naturally harmonious human-robot interaction of wearable exoskeleton robots.%人体下肢生物力学建模与仿真是穿戴式外骨骼机器人系统开发的一个重要内容。对其研究所获得相关的理论与技术方法对生物动力学、康复医学、假肢及运动康复器械设计等领域的发展具有促进作用。本文以人体下肢生物力系统为研究对象,概括和总结了国内外下肢建模与仿真技术的研究现状,就目前普遍采用的基于Lagrange 方程和角动量定理的多刚体模型法、仿真软件建模法、Hill三元素法、黑箱训练等方法进行了详细的分析,并对研究趋势进行了展望。本文所综述的动力学建模与仿真验证方法对实现穿戴式外骨骼机器人和谐自然人机交互设计具有重要的指导意义。

  18. Minicomputer For Biomechanical Research

    Science.gov (United States)

    Shierman, Gail; Rhymes, Tom

    1982-02-01

    The increased capabilities of minicomputers today allows a biomechanics laboratory to establish a self-contained computer system for a reasonable price. The system includes a microprocessor, a printer and a CRT. Analog to digital conversion is an important feature to consider as well as the ability to interface with a mainframe computer. A minicomputer adapted for film analysis should be a consideration for data analysis when developing a cinematography laboratory. For the past 10-15 years the area of biomechanics has enjoyed the advances in technology. Equipment and instrumentation once used exclusively by engineers and physicists have become readily available to those involved with snorts analyses. Among the various pieces of equipment accessible to biomechanists today, probably the most important one is the computer. At this time several biomechanics laboratories are using the computer to analyze kinematic and kinetic data obtained from film. The computer in use at each school is generally the main University or College computer with a remote terminal set-up in the biomechanics laboratory. This system functions well if there is adequate response from the time-sharing system of the main computer, and if there is at least one knowledgeable technician available. With the trend toward minicomputers today, their increased capabilities, and their ease of use, a self-contained minicomputer system in the biomechanics laboratory appears to be a viable alternative. The computer system in use in the ,Biomechanics Laboratory at the University of Oklahoma is based around the Cromemco Z2D computer connected to a PCD motion analyzer (Figure 1). The data acquisition system consists of the eight-bit microprocessor-based minicomputer connected to an analog to digital converter (ADC). As a terminal for the computer, we have either a video display unit or a Model 43 Teletype. The Model 43 provides a hard copy out-put while the video terminal provides much faster I/O, useful for

  19. Large Scale Tissue Morphogenesis Simulation on Heterogenous Systems Based on a Flexible Biomechanical Cell Model.

    Science.gov (United States)

    Jeannin-Girardon, Anne; Ballet, Pascal; Rodin, Vincent

    2015-01-01

    The complexity of biological tissue morphogenesis makes in silico simulations of such system very interesting in order to gain a better understanding of the underlying mechanisms ruling the development of multicellular tissues. This complexity is mainly due to two elements: firstly, biological tissues comprise a large amount of cells; secondly, these cells exhibit complex interactions and behaviors. To address these two issues, we propose two tools: the first one is a virtual cell model that comprise two main elements: firstly, a mechanical structure (membrane, cytoskeleton, and cortex) and secondly, the main behaviors exhibited by biological cells, i.e., mitosis, growth, differentiation, molecule consumption, and production as well as the consideration of the physical constraints issued from the environment. An artificial chemistry is also included in the model. This virtual cell model is coupled to an agent-based formalism. The second tool is a simulator that relies on the OpenCL framework. It allows efficient parallel simulations on heterogenous devices such as micro-processors or graphics processors. We present two case studies validating the implementation of our model in our simulator: cellular proliferation controlled by cell signalling and limb growth in a virtual organism.

  20. Modelling, stability and biomechanical implications of three DOF passive bipedal gait

    Directory of Open Access Journals (Sweden)

    Máximo Alejandro Roa Garzón

    2010-04-01

    Full Text Available Passive dynamic walkers can achieve a steady gait down an inclined plane simply by the influence of gravity. This article presents the modelling of a 3 DOF passive bipedal walker, searching for a relationship between gait characteristics, the robot’s physical properties and the slope of the plane. The proposed adimensional dynamical model’s equations are also given, implementing and modelling the dynamics is described and the main results are presented. Limits on robotic parameters leading to establishing stable limit cycles are also analysed as perio-dic doubling bifurcations appear to be natural in passive gait. Interesting results arose when comparing natural passive walking with human bipedal locomotion.

  1. Multimodal, high-dimensional, model-based, Bayesian inverse problems with applications in biomechanics

    Science.gov (United States)

    Franck, I. M.; Koutsourelakis, P. S.

    2017-01-01

    This paper is concerned with the numerical solution of model-based, Bayesian inverse problems. We are particularly interested in cases where the cost of each likelihood evaluation (forward-model call) is expensive and the number of unknown (latent) variables is high. This is the setting in many problems in computational physics where forward models with nonlinear PDEs are used and the parameters to be calibrated involve spatio-temporarily varying coefficients, which upon discretization give rise to a high-dimensional vector of unknowns. One of the consequences of the well-documented ill-posedness of inverse problems is the possibility of multiple solutions. While such information is contained in the posterior density in Bayesian formulations, the discovery of a single mode, let alone multiple, poses a formidable computational task. The goal of the present paper is two-fold. On one hand, we propose approximate, adaptive inference strategies using mixture densities to capture multi-modal posteriors. On the other, we extend our work in [1] with regard to effective dimensionality reduction techniques that reveal low-dimensional subspaces where the posterior variance is mostly concentrated. We validate the proposed model by employing Importance Sampling which confirms that the bias introduced is small and can be efficiently corrected if the analyst wishes to do so. We demonstrate the performance of the proposed strategy in nonlinear elastography where the identification of the mechanical properties of biological materials can inform non-invasive, medical diagnosis. The discovery of multiple modes (solutions) in such problems is critical in achieving the diagnostic objectives.

  2. Biomechanical analysis of the anterior displacement of Tibial tuberosity (Maquet operation: A computer model study

    Directory of Open Access Journals (Sweden)

    Farahmand F

    2000-08-01

    Full Text Available Computer model of the patellofemoral joint was developed and the effects on the anterior displacement of the tibial tuberosity were investigated. The input geometrical and verification data for the model were obtained form an experimental study on a cadaver knee, mounted in an instron machine. The computer program found the configuration of the patellofemoral joint which satified both the geometrical and force equilibrium conditions, simultaneously, using a trial graphical approach.verification of the model was achieved by determining the patellar sagittal plane motion and patellofemoral contact locations and comparing the results with the experimental results of the same specimen and published data. Simulation of the anterior displacement of the tibial tuberosity by the model showed that the location of contact area migrates distally on the femur and proximally on the patella following operation. The contact force of the patellofemoral joint decreased significantly by 70% at full extension, 30% at 30 degrees flexion and around 15% at higher flexion angles for a 1 cm anterior displacement of the tibial tuberosity and nearly doubled for a 2cm anterior displacement. The change of the effective moment are of the quadriceps was not considerable. The results suggest that the major effect of the Maquet operation on the contact force appears in extension and mid-flexion rather than deep flexion amgles. Further displacement of the tuberosity enhances the reduction of the contact force, however, the total reduction is less than what was predicted by Maquet. The change of the contact location relieves pain in short term but causes hyperpressure in the proximal retropatellar surface which might be detrimental in long term

  3. 21 CFR 880.6230 - Tongue depressor.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tongue depressor. 880.6230 Section 880.6230 Food... § 880.6230 Tongue depressor. (a) Identification. A tongue depressor is a device intended to displace the tongue to facilitate examination of the surrounding organs and tissues. (b) Classification. Class...

  4. A biomechanical model for cell polarization and intercalation during Drosophila germband extension

    Science.gov (United States)

    Lan, Haihan; Wang, Qiming; Fernandez-Gonzalez, Rodrigo; Feng, James J.

    2015-10-01

    Germband extension during Drosophila development features the merging of cells along the dorsal-ventral (DV) axis and their separation along the anterior-posterior (AP) axis. This intercalation process involves planar cell polarity, anisotropic contractile forces along cell edges, and concerted cell deformation and movement. Although prior experiments have probed each of these factors separately, the connection among them remains unclear. This paper presents a chemo-mechanical model that integrates the three factors into a coherent framework. The model predicts the polarization of Rho-kinase, myosin and Bazooka downstream of an anisotropic Shroom distribution. In particular, myosin accumulates on cell edges along the DV axis, causing them to contract into a vertex. Subsequently, medial myosin in the cells anterior and posterior to the vertex helps to elongate it into a new edge parallel to the body axis. Thus, the tissue extends along the AP axis and narrows in the transverse direction through neighbor exchange. Model predictions of the polarity of the proteins and cell and tissue deformation are in good agreement with experimental observations.

  5. OSIRIS observations of a tongue of NOx in the lower stratosphere at the Antarctic vortex edge: comparison with a high-resolution simulation from the Global Environmental Multiscale (GEM) model

    Energy Technology Data Exchange (ETDEWEB)

    Sioris, C.E.; McLinden, C.A.; Rochon, Y.J.; McElroy, C.T. [Environment Canada, Toronto, ON (Canada). Atmospheric Science and Technology Directorate; Chabrillat, S. [Belgian Inst. for Space Aeronomy, Brussels (Belgium); Haley, C.S. [York Univ., Toronto, ON (Canada); Menard, R.; Charron, M. [Environment Canada, Dorval, ON (Canada). Atmospheric Science and Technology Directorate

    2007-11-15

    An optical spectrograph and infrared imager system (OSIRIS) aboard the Odin satellite measures limb-scattered sunlight in the 280 to 810 nm range. This paper addressed the challenge of interpreting nitrogen dioxide (NO{sub 2}) profile observations in the polar lower stratosphere. Interpretations of these profile observations can be facilitated by first converting the measurements to NO{sub x} using a photochemical model in order to compare directly with simulated NO{sub x} from a 3-dimensional chemical transport model such as the Global Environmental Multiscale (GEM) model. In this study, GEM was used to simulate a tongue of NO{sub x} observed by OSIRIS as it circulated inside the Antarctic vortex edge. The objective was to clarify one of several OSIRIS observations of enhanced lower stratospheric NO{sub 2} in the Antarctic in early austral spring. Another objective was to demonstrate the variability in lower stratospheric NO{sub x} at polar latitudes due to dynamical processes. Selected NOx profiles of the Antarctic lower stratosphere inferred from OSIRIS NO{sub 2} observations were presented from the austral spring of 2003. A tongue of NOx at 100 hPa was observed, with a concentration typical of the middle stratosphere. GEM simulations revealed that this small-scale tongue of NOx-rich air descended into the lower stratosphere. The tongue was formed as a result of a Rossby wave breaking, transporting NOx from the pole, where larger concentrations had recently appeared, to the edge of the vortex. A detailed illustration of the 3-dimensional structure of the breaking wave was also presented. 17 refs., 1 tab., 10 figs.

  6. Diagnostic Method of Diabetes Based on Support Vector Machine and Tongue Images

    Science.gov (United States)

    Hu, Xiaojuan; Chen, Qingguang; Tu, Liping; Huang, Jingbin; Cui, Ji

    2017-01-01

    Objective. The purpose of this research is to develop a diagnostic method of diabetes based on standardized tongue image using support vector machine (SVM). Methods. Tongue images of 296 diabetic subjects and 531 nondiabetic subjects were collected by the TDA-1 digital tongue instrument. Tongue body and tongue coating were separated by the division-merging method and chrominance-threshold method. With extracted color and texture features of the tongue image as input variables, the diagnostic model of diabetes with SVM was trained. After optimizing the combination of SVM kernel parameters and input variables, the influences of the combinations on the model were analyzed. Results. After normalizing parameters of tongue images, the accuracy rate of diabetes predication was increased from 77.83% to 78.77%. The accuracy rate and area under curve (AUC) were not reduced after reducing the dimensions of tongue features with principal component analysis (PCA), while substantially saving the training time. During the training for selecting SVM parameters by genetic algorithm (GA), the accuracy rate of cross-validation was grown from 72% or so to 83.06%. Finally, we compare with several state-of-the-art algorithms, and experimental results show that our algorithm has the best predictive accuracy. Conclusions. The diagnostic method of diabetes on the basis of tongue images in Traditional Chinese Medicine (TCM) is of great value, indicating the feasibility of digitalized tongue diagnosis. PMID:28133611

  7. Diagnostic Method of Diabetes Based on Support Vector Machine and Tongue Images

    Directory of Open Access Journals (Sweden)

    Jianfeng Zhang

    2017-01-01

    Full Text Available Objective. The purpose of this research is to develop a diagnostic method of diabetes based on standardized tongue image using support vector machine (SVM. Methods. Tongue images of 296 diabetic subjects and 531 nondiabetic subjects were collected by the TDA-1 digital tongue instrument. Tongue body and tongue coating were separated by the division-merging method and chrominance-threshold method. With extracted color and texture features of the tongue image as input variables, the diagnostic model of diabetes with SVM was trained. After optimizing the combination of SVM kernel parameters and input variables, the influences of the combinations on the model were analyzed. Results. After normalizing parameters of tongue images, the accuracy rate of diabetes predication was increased from 77.83% to 78.77%. The accuracy rate and area under curve (AUC were not reduced after reducing the dimensions of tongue features with principal component analysis (PCA, while substantially saving the training time. During the training for selecting SVM parameters by genetic algorithm (GA, the accuracy rate of cross-validation was grown from 72% or so to 83.06%. Finally, we compare with several state-of-the-art algorithms, and experimental results show that our algorithm has the best predictive accuracy. Conclusions. The diagnostic method of diabetes on the basis of tongue images in Traditional Chinese Medicine (TCM is of great value, indicating the feasibility of digitalized tongue diagnosis.

  8. Diagnostic Method of Diabetes Based on Support Vector Machine and Tongue Images.

    Science.gov (United States)

    Zhang, Jianfeng; Xu, Jiatuo; Hu, Xiaojuan; Chen, Qingguang; Tu, Liping; Huang, Jingbin; Cui, Ji

    2017-01-01

    Objective. The purpose of this research is to develop a diagnostic method of diabetes based on standardized tongue image using support vector machine (SVM). Methods. Tongue images of 296 diabetic subjects and 531 nondiabetic subjects were collected by the TDA-1 digital tongue instrument. Tongue body and tongue coating were separated by the division-merging method and chrominance-threshold method. With extracted color and texture features of the tongue image as input variables, the diagnostic model of diabetes with SVM was trained. After optimizing the combination of SVM kernel parameters and input variables, the influences of the combinations on the model were analyzed. Results. After normalizing parameters of tongue images, the accuracy rate of diabetes predication was increased from 77.83% to 78.77%. The accuracy rate and area under curve (AUC) were not reduced after reducing the dimensions of tongue features with principal component analysis (PCA), while substantially saving the training time. During the training for selecting SVM parameters by genetic algorithm (GA), the accuracy rate of cross-validation was grown from 72% or so to 83.06%. Finally, we compare with several state-of-the-art algorithms, and experimental results show that our algorithm has the best predictive accuracy. Conclusions. The diagnostic method of diabetes on the basis of tongue images in Traditional Chinese Medicine (TCM) is of great value, indicating the feasibility of digitalized tongue diagnosis.

  9. Weighted Nuclear Norm Minimization Based Tongue Specular Reflection Removal

    Directory of Open Access Journals (Sweden)

    Zhenchao Cui

    2015-01-01

    Full Text Available In computational tongue diagnosis, specular reflection is generally inevitable in tongue image acquisition, which has adverse impact on the feature extraction and tends to degrade the diagnosis performance. In this paper, we proposed a two-stage (i.e., the detection and inpainting pipeline approach to address this issue: (i by considering both highlight reflection and subreflection areas, a superpixel-based segmentation method was adopted for the detection of the specular reflection areas; (ii by extending the weighted nuclear norm minimization (WNNM model, a nonlocal inpainting method is proposed for specular reflection removal. Experimental results on synthetic and real images show that the proposed method is accurate in detecting the specular reflection areas and is effective in restoring tongue image with more natural texture information of tongue body.

  10. Biomechanical implications of skeletal muscle hypertrophy and atrophy: a musculoskeletal model.

    Science.gov (United States)

    Vigotsky, Andrew D; Contreras, Bret; Beardsley, Chris

    2015-01-01

    Muscle hypertrophy and atrophy occur frequently as a result of mechanical loading or unloading, with implications for clinical, general, and athletic populations. The effects of muscle hypertrophy and atrophy on force production and joint moments have been previously described. However, there is a paucity of research showing how hypertrophy and atrophy may affect moment arm (MA) lengths. The purpose of this model was to describe the mathematical relationship between the anatomical cross-sectional area (ACSA) of a muscle and its MA length. In the model, the ACSAs of the biceps brachii and brachialis were altered to hypertrophy up to twice their original size and to atrophy to one-half of their original size. The change in MA length was found to be proportional to the arcsine of the square root of the change in ACSA. This change in MA length may be a small but important contributor to strength, especially in sports that require large joint moments at slow joint angular velocities, such as powerlifting. The paradoxical implications of the increase in MA are discussed, as physiological factors influencing muscle contraction velocity appear to favor a smaller MA length for high velocity movements but a larger muscle MA length for low velocity, high force movements.

  11. Biomechanical implications of skeletal muscle hypertrophy and atrophy: a musculoskeletal model

    Directory of Open Access Journals (Sweden)

    Andrew D. Vigotsky

    2015-11-01

    Full Text Available Muscle hypertrophy and atrophy occur frequently as a result of mechanical loading or unloading, with implications for clinical, general, and athletic populations. The effects of muscle hypertrophy and atrophy on force production and joint moments have been previously described. However, there is a paucity of research showing how hypertrophy and atrophy may affect moment arm (MA lengths. The purpose of this model was to describe the mathematical relationship between the anatomical cross-sectional area (ACSA of a muscle and its MA length. In the model, the ACSAs of the biceps brachii and brachialis were altered to hypertrophy up to twice their original size and to atrophy to one-half of their original size. The change in MA length was found to be proportional to the arcsine of the square root of the change in ACSA. This change in MA length may be a small but important contributor to strength, especially in sports that require large joint moments at slow joint angular velocities, such as powerlifting. The paradoxical implications of the increase in MA are discussed, as physiological factors influencing muscle contraction velocity appear to favor a smaller MA length for high velocity movements but a larger muscle MA length for low velocity, high force movements.

  12. From time series analysis to a biomechanical multibody model of the human eye

    Energy Technology Data Exchange (ETDEWEB)

    Pascolo, P. [Dipartimento di Ingegneria Civile, Universita di Udine, Udine (Italy); Dipartimento di Bioingegneria, CISM, Udine (Italy)], E-mail: paolo.pascolo@uniud.it; Carniel, R. [Dipartimento di Georisorse e Territorio, Universita di Udine, Udine (Italy)], E-mail: roberto.carniel@uniud.it

    2009-04-30

    A mechanical model of the human eye is presented aimed at estimating the level of muscular activation. The applicability of the model in the biomedical field is discussed. Human eye movements studied in the laboratory are compared with the ones produced by a virtual eye described in kinematical terms and subject to the dynamics of six actuators, as many as the muscular systems devoted to the eye motion control. The definition of an error function between the experimental and the numerical response and the application of a suitable law that links activation and muscular force are at the base of the proposed methodology. The aim is the definition of a simple conceptual tool that could help the specialist in the diagnosis of potential physiological disturbances of saccadic and nystagmic movements but can also be extended in a second phase when more sophisticated data become available. The work is part of a collaboration between the Functional Mechanics Laboratory of the University and the Neurophysiopatology Laboratory of the 'S. Maria della Misericordia' Hospital in Udine, Italy.

  13. A biomechanical model correlating shoulder kinetics to pain in young baseball pitchers.

    Science.gov (United States)

    Keeley, David W; Oliver, Gretchen D; Dougherty, Christopher P

    2012-10-01

    Previous work has postulated that shoulder pain may be associated with increases in both peak shoulder anterior force and peak shoulder proximal force. Unfortunately these relationships have yet to be quantified. Thus, the purpose of this study was to associate these kinetic values with reported shoulder pain in youth baseball pitchers. Nineteen healthy baseball pitchers participated in this study. Segment based reference systems and established calculations were utilized to identify peak shoulder anterior force and peak shoulder proximal force. A medical history questionnaire was utilized to identify shoulder pain. Following collection of these data, the strength of the relationships between both peak shoulder anterior force and peak shoulder proximal force and shoulder pain were analyzed. Although peak anterior force was not significantly correlated to shoulder pain, peak proximal force was. These results lead to the development of a single variable logistic regression model able to accurately predict 84.2% of all cases and 71.4% of shoulder pain cases. This model indicated that for every 1 N increase in peak proximal force, there was a corresponding 4.6% increase in the likelihood of shoulder pain. The magnitude of peak proximal force is both correlated to reported shoulder pain and capable of being used to accurately predict the likelihood of experiencing shoulder pain. It appears that those pitchers exhibiting high magnitudes of peak proximal force are significantly more likely to report experiencing shoulder pain than those who generate lower magnitudes of peak proximal force.

  14. Involvement of peripheral artemin signaling in tongue pain: possible mechanism in burning mouth syndrome.

    Science.gov (United States)

    Shinoda, Masamichi; Takeda, Mamoru; Honda, Kuniya; Maruno, Mitsuru; Katagiri, Ayano; Satoh-Kuriwada, Shizuko; Shoji, Noriaki; Tsuchiya, Masahiro; Iwata, Koichi

    2015-12-01

    Burning mouth syndrome is characterized by altered sensory qualities, namely tongue pain hypersensitivity. We found that the mRNA expression of Artemin (Artn) in the tongue mucosa of patients with burning mouth syndrome was significantly higher than that of control subjects, and we developed a mouse model of burning mouth syndrome by application of 2,4,6-trinitrobenzene sulfonic acid (TNBS) diluted with 50% ethanol to the dorsum of the tongue. TNBS treatment to the tongue induced persistent, week-long, noninflammatory tongue pain and a significant increase in Artn expression in the tongue mucosa and marked tongue heat hyperalgesia. Following TNBS treatment, the successive administration of the transient receptor potential vanilloid 1 (TRPV1) antagonist SB366791 or neutralizing anti-Artn antibody completely inhibited the heat hyperalgesia. The number of glial cell line-derived neurotrophic factor family receptor α3 (GFRα3)-positive and TRPV1-positive trigeminal ganglion (TG) neurons innervating the tongue significantly increased following TNBS treatment and was significantly reduced by successive administration of neutralizing anti-Artn antibody. The capsaicin-induced current in TG neurons innervating the tongue was enhanced following TNBS treatment and was inhibited by local administration of neutralizing anti-Artn antibody to the tongue. These results suggest that the overexpression of Artn in the TNBS-treated tongue increases the membrane excitability of TG neurons innervating the tongue by increasing TRPV1 sensitivity, which causes heat hyperalgesia. This model may be useful for the study of tongue pain hypersensitivity associated with burning mouth syndrome.

  15. Pulsed electromagnetic field treatment enhances healing callus biomechanical properties in an animal model of osteoporotic fracture.

    Science.gov (United States)

    Androjna, Caroline; Fort, Brian; Zborowski, Maciej; Midura, Ronald J

    2014-09-01

    Delayed bone healing has been noted in osteoporosis patients and in the ovariectomized (OVX) rat model of estrogen-depletion osteopenia. Pulsed electromagnetic field (PEMF) devices are clinically approved as an adjunct to cervical fusion surgery in patients at high risk for non-fusion and for the treatment of fracture non-unions. These bone growth stimulating devices also accelerate the healing of fresh fracture repair in skeletally mature normal rats but have not been tested for efficacy to accelerate and/or enhance the delayed bone repair process in OVX rats. The current study tested the hypothesis that daily PEMF treatments would improve the fracture healing response in skeletally mature OVX rats. By 6 weeks of healing, PEMF treatments resulted in improved hard callus elastic modulus across fibula fractures normalizing the healing process in OVX rats with respect to this mechanical property. Radiographic evidence showed an improved hard callus bridging across fibula fractures in OVX rats treated with PEMF as compared to sham treatments. These findings provide a scientific rationale for investigating whether PEMF might improve bone-healing responses in at-risk osteoporotic patients.

  16. A Biomechanical Model of the Inner Ear: Numerical Simulation of the Caloric Test

    Directory of Open Access Journals (Sweden)

    Shuang Shen

    2013-01-01

    Full Text Available Whether two vertical semicircular canals can receive thermal stimuli remains controversial. This study examined the caloric response in the three semicircular canals to the clinical hot caloric test using the finite element method. The results of the developed model showed the horizontal canal (HC cupula maximally deflected to the utricle side by approximately 3 μm during the hot supine test. The anterior canal cupula began to receive the caloric stimuli about 20 s after the HC cupula, and it maximally deflected to the canal side by 0.55 μm. The posterior canal cupula did not receive caloric stimuli until approximately 40 s after the HC cupula, and it maximally deflected to the canal side by 0.34 μm. Although the endolymph flow and the cupular deformation change with respect to the head position during the test, the supine test ensures the maximal caloric response in the HC, but no substantial improvement for the responses of the two vertical canals was observed. In conclusion, while the usual supine test is the optimum test for evaluating the functions of the inner ear, more irrigation time is needed in order to effectively clinically examine the vertical canals.

  17. A biomechanical model of the inner ear: numerical simulation of the caloric test.

    Science.gov (United States)

    Shen, Shuang; Liu, Yingxi; Sun, Xiuzhen; Zhao, Wei; Su, Yingfeng; Yu, Shen; Liu, Wenlong

    2013-01-01

    Whether two vertical semicircular canals can receive thermal stimuli remains controversial. This study examined the caloric response in the three semicircular canals to the clinical hot caloric test using the finite element method. The results of the developed model showed the horizontal canal (HC) cupula maximally deflected to the utricle side by approximately 3 μm during the hot supine test. The anterior canal cupula began to receive the caloric stimuli about 20 s after the HC cupula, and it maximally deflected to the canal side by 0.55 μm. The posterior canal cupula did not receive caloric stimuli until approximately 40 s after the HC cupula, and it maximally deflected to the canal side by 0.34 μm. Although the endolymph flow and the cupular deformation change with respect to the head position during the test, the supine test ensures the maximal caloric response in the HC, but no substantial improvement for the responses of the two vertical canals was observed. In conclusion, while the usual supine test is the optimum test for evaluating the functions of the inner ear, more irrigation time is needed in order to effectively clinically examine the vertical canals.

  18. Proximal Humeral Fractures: A Biomechanical Comparison of Locking Plate Constructs in a Cadaveric 3-Part Fracture Model

    OpenAIRE

    2010-01-01

    The purpose of our study was to biomechanically compare, under cyclic loading conditions, fracture site motion, humeral head collapse, and intra-articular hardware penetration in simulated 3-part osteoporotic proximal humeral fractures stabilized with 1 of 2 locking-plate constructs. We performed fixation on simulated 3-part proximal humeral fractures in 10 pairs of cadaveric osteoporotic humeri with a Hand Innovations S3 Proximal Humerus Plate (S3 plate) or an LCP Proximal Humerus Plate (LCP...

  19. An introduction to biomechanics solids and fluids, analysis and design

    CERN Document Server

    Humphrey, Jay D

    2004-01-01

    Designed to meet the needs of undergraduate students, Introduction to Biomechanics takes the fresh approach of combining the viewpoints of both a well-respected teacher and a successful student. With an eye toward practicality without loss of depth of instruction, this book seeks to explain the fundamental concepts of biomechanics. With the accompanying web site providing models, sample problems, review questions and more, Introduction to Biomechanics provides students with the full range of instructional material for this complex and dynamic field.

  20. Computational Biomechanics Theoretical Background and BiologicalBiomedical Problems

    CERN Document Server

    Tanaka, Masao; Nakamura, Masanori

    2012-01-01

    Rapid developments have taken place in biological/biomedical measurement and imaging technologies as well as in computer analysis and information technologies. The increase in data obtained with such technologies invites the reader into a virtual world that represents realistic biological tissue or organ structures in digital form and allows for simulation and what is called “in silico medicine.” This volume is the third in a textbook series and covers both the basics of continuum mechanics of biosolids and biofluids and the theoretical core of computational methods for continuum mechanics analyses. Several biomechanics problems are provided for better understanding of computational modeling and analysis. Topics include the mechanics of solid and fluid bodies, fundamental characteristics of biosolids and biofluids, computational methods in biomechanics analysis/simulation, practical problems in orthopedic biomechanics, dental biomechanics, ophthalmic biomechanics, cardiovascular biomechanics, hemodynamics...

  1. The effect of desalivation on the malignant transformation of the tongue epithelium and associated stromal myofibroblasts in a rat 4-nitroquinoline 1-oxide-induced carcinogenesis model.

    Science.gov (United States)

    Vered, Marilena; Grinstein-Koren, Osnat; Reiter, Shoshana; Allon, Irit; Dayan, Dan

    2010-08-01

    The aim of our study was to analyse desalivated rat tongue epithelium for histopathological changes, proliferating cell nuclear antigen (PCNA), and epithelium-associated stromal myofibroblasts [SMF; alpha-smooth muscle actin (alphaSMA)] following 0.001% 4-nitroquinoline 1-oxide (4NQO) administration in drinking water. Results were compared with those of identically treated but salivated specimens. 4NQO was administered for 7, 14, 22 and 28 weeks. Tongue length was divided into anterior, middle and posterior 'thirds'. The histopathological changes per 'third' were scored as normal epithelium, hyperplasia, dysplasia, carcinoma-in-situ, and superficial and invasive carcinoma. The PCNA and alphaSMA stains were assessed by a point-counting method. At all time points, the histopathological changes in the anterior and middle thirds were higher in the desalivated than in the salivated group (P 0.05). PCNA scores were significantly lower in the desalivated vs. the salivated group at almost all time points and tongue thirds (P tongue epithelium in the early stages. PCNA cannot be regarded as a marker of proliferation and probably contributes to this process by other mechanisms. Emergence of SMF seems to be highly dependent on growth factors from saliva in addition to factors from cancerous cells.

  2. Biomechanics of the brain

    CERN Document Server

    Miller, Karol

    2011-01-01

    With contributions from scientists at major institutions, this book presents an introduction to brain anatomy for engineers and scientists. It provides, for the first time, a comprehensive resource in the field of brain biomechanics.

  3. Biomechanically Engineered Athletes.

    Science.gov (United States)

    Perry, Tekla S.

    1991-01-01

    The real-world meeting of electronics, computer monitoring, control systems, and mathematics, introduced in the context of sports, is described. Recent advances in the field of biomechanics and its use in improving athletic performance are discussed. (KR)

  4. Fundamentals of Biomechanics

    OpenAIRE

    Duane Knudson

    2007-01-01

    DESCRIPTION This book provides a broad and in-depth theoretical and practical description of the fundamental concepts in understanding biomechanics in the qualitative analysis of human movement. PURPOSE The aim is to bring together up-to-date biomechanical knowledge with expert application knowledge. Extensive referencing for students is also provided. FEATURES This textbook is divided into 12 chapters within four parts, including a lab activities section at the end. The division is as follow...

  5. WE-AB-BRA-02: Development of Biomechanical Models to Describe Dose-Volume Response to Liver Stereotactic Body Radiation Therapy (SBRT) Patients

    Energy Technology Data Exchange (ETDEWEB)

    McCulloch, M; Polan, D; Feng, M; Lawrence, T; Haken, R Ten; Brock, K [University of Michigan, Ann Arbor, MI (United States)

    2015-06-15

    Purpose: Previous studies have shown that radiotherapy treatment for liver metastases causes marked liver hypertrophy in areas receiving low dose and atrophy/fibrosis in areas receiving high dose. The purpose of this work is to develop and evaluate a biomechanical model-based dose-response model to describe these liver responses to SBRT. Methods: In this retrospective study, a biomechanical model-based deformable registration algorithm, Morfeus, was expanded to include dose-based boundary conditions. Liver and tumor volumes were contoured on the planning images and CT/MR images three months post-RT and converted to finite element models. A thermal expansion-based relationship correlating the delivered dose and volume response was generated from 22 patients previously treated. This coefficient, combined with the planned dose, was applied as an additional boundary condition to describe the volumetric response of the liver of an additional cohort of metastatic liver patients treated with SBRT. The accuracy of the model was evaluated based on overall volumetric liver comparisons and the target registration error (TRE) using the average deviations in positions of identified vascular bifurcations on each set of registered images, with a target accuracy of the 2.5mm isotropic dose grid (vector dimension 4.3mm). Results: The thermal expansion coefficient models the volumetric change of the liver to within 3%. The accuracy of Morfeus with dose-expansion boundary conditions a TRE of 5.7±2.8mm compared to 11.2±3.7mm using rigid registration and 8.9±0.28mm using Morfeus with only spatial boundary conditions. Conclusion: A biomechanical model has been developed to describe the volumetric and spatial response of the liver to SBRT. This work will enable the improvement of correlating functional imaging with delivered dose, the mapping of the delivered dose from one treatment onto the planning images for a subsequent treatment, and will further provide information to assist

  6. 活体成年小鼠舌黏膜下植入蛋白凝胶颗粒的方法学研究%A mouse model of agarose beads implantation in the tongue

    Institute of Scientific and Technical Information of China (English)

    李瑞奇; 黄晓峰; 张方明

    2014-01-01

    Objective:To establish a method in which exogenous agarose beads are implanted under the epithelium of the tongue in adult mouse.Methods:10 male C57BL mice of postnatal 90.5 days old were selected in this study. After anesthetized by injection of pentobarbital sodium, the agarose beads soaked with BSA were implanted under the epithelium of the tongues. 48 hours later, the mice were sacrificed, and the tongues were dissected, fixed in 4% paraformaldehyde, dehydrated with alcohol, embedded in wax and cut into slices for HE and immunohistochemical staining.Results:After 48 hours, all mice were alive, and there were no obvious inflammatory lesions on the tongue mucosa. The histological results showed that the beads were located submucously in the tongue and the implanted protein did not influence the expression of BrdU and PCNA in the lingual epithelium.Conclusion:we successfully established an animal model to implant agarose beads soaked with proteins under the mouse’s epithelium in vivo.%目的:建立活体动物舌黏膜植入外源性蛋白凝胶颗粒的方法。方法:出生后90.5d的C57BL小鼠经戊巴比妥钠麻醉后,于舌黏膜下植入小牛血清(bovine serum albumin,BSA)的凝胶颗粒。实验后48h,取小鼠舌组织固定、脱水、包埋、切片后进行HE染色、 Brdu染色及PCNA染色。结果:实验后48h,小鼠舌黏膜无明显炎性病变,染色结果显示凝胶颗粒的植入对上皮内BrdU和PCNA的表达无影响。结论:本研究成功地建立了舌黏膜下植入蛋白凝胶颗粒的方法,为将来药物和蛋白质诱导活体动物器官局部增殖、分化和凋亡奠定基础。

  7. Biomechanics of whiplash injury

    Institute of Scientific and Technical Information of China (English)

    CHEN Hai-bin; King H YANG; WANG Zheng-guo

    2009-01-01

    Despite a large number of rear-end collisions on the road and a high frequency of whiplash injuries reported, the mechanism of whiplash injuries is not completely understood. One of the reasons is that the injury is not necessarily accompanied by obvious tissue damage detectable by X-ray or MRI. An extensive series of biomechanics studies, including injury epidemiology, neck kinematics,facet capsule ligament mechanics, injury mechanisms and injury criteria, were undertaken to help elucidate these whiplash injury mechanisms and gain a better understanding of cervical facet pain. These studies provide the following evidences to help explain the mechanisms of the whiplash injury: (1) Whiplash injuries are generally considered to be a soft tissue injury of the neck with symptoms such as neck pain and stiffness, shoulder weakness, dizziness, headache and memory loss, etc. (2) Based on kinematical studies on the cadaver and volunteers, there are three distinct periods that have the potential to cause injury to the neck. In the first stage, flexural deformation of the neck is observed along with a loss of cervical lordosis; in the second stage, the cervical spine assumes an S-shaped curve as the lower vertebrae begin to extend and gradually cause the upper vertebrae to extend; during the final stage, the entire neck is extended due to the extension moments at both ends. (3)The in vivo environment afforded by rodent models of injury offers particular utility for linking mechanics, nociception and behavioral outcomes. Experimental findings have examined strains across the facet joint as a mechanism of whiplash injury, and suggested a capsular strain threshold or a vertebral distraction threshold for whiplash-related injury,potentially producing neck pain. (4) Injuries to the facet capsule region of the neck are a major source of post-crash pain. There are several hypotheses on how whiplash-associated injury may occur and three of these injuries are related to strains within

  8. Biomechanics of whiplash injury.

    Science.gov (United States)

    Chen, Hai-bin; Yang, King H; Wang, Zheng-guo

    2009-10-01

    Despite a large number of rear-end collisions on the road and a high frequency of whiplash injuries reported, the mechanism of whiplash injuries is not completely understood. One of the reasons is that the injury is not necessarily accompanied by obvious tissue damage detectable by X-ray or MRI. An extensive series of biomechanics studies, including injury epidemiology, neck kinematics, facet capsule ligament mechanics, injury mechanisms and injury criteria, were undertaken to help elucidate these whiplash injury mechanisms and gain a better understanding of cervical facet pain. These studies provide the following evidences to help explain the mechanisms of the whiplash injury: (1) Whiplash injuries are generally considered to be a soft tissue injury of the neck with symptoms such as neck pain and stiffness, shoulder weakness, dizziness, headache and memory loss, etc. (2) Based on kinematical studies on the cadaver and volunteers, there are three distinct periods that have the potential to cause injury to the neck. In the first stage, flexural deformation of the neck is observed along with a loss of cervical lordosis; in the second stage, the cervical spine assumes an S-shaped curve as the lower vertebrae begin to extend and gradually cause the upper vertebrae to extend; during the final stage, the entire neck is extended due to the extension moments at both ends. (3) The in vivo environment afforded by rodent models of injury offers particular utility for linking mechanics, nociception and behavioral outcomes. Experimental findings have examined strains across the facet joint as a mechanism of whiplash injury, and suggested a capsular strain threshold or a vertebral distraction threshold for whiplash-related injury, potentially producing neck pain. (4) Injuries to the facet capsule region of the neck are a major source of post-crash pain. There are several hypotheses on how whiplash-associated injury may occur and three of these injuries are related to strains

  9. Fast marching over the 2D Gabor magnitude domain for tongue body segmentation

    Science.gov (United States)

    Cui, Zhenchao; Zhang, Hongzhi; Zhang, David; Li, Naimin; Zuo, Wangmeng

    2013-12-01

    Tongue body segmentation is a prerequisite to tongue image analysis and has recently received considerable attention. The existing tongue body segmentation methods usually involve two key steps: edge detection and active contour model (ACM)-based segmentation. However, conventional edge detectors cannot faithfully detect the contour of the tongue body, and the initialization of ACM suffers from the edge discontinuity problem. To address these issues, we proposed a novel tongue body segmentation method, GaborFM, which initializes ACM by performing fast marching over the two-dimensional (2D) Gabor magnitude domain of the tongue images. For the enhancement of the contour of the tongue body, we used the 2D Gabor magnitude-based detector. To cope with the edge discontinuity problem, the fast marching method was utilized to connect the discontinuous contour segments, resulting in a closed and continuous tongue body contour for subsequent ACM-based segmentation. Qualitative and quantitative results showed that GaborFM is superior to the other methods for tongue body segmentation.

  10. Tongue pressure during swallowing is decreased in patients with Duchenne muscular dystrophy.

    Science.gov (United States)

    Hamanaka-Kondoh, Sato; Kondoh, Jugo; Tamine, Ken-Ichi; Hori, Kazuhiro; Fujiwara, Shigehiro; Maeda, Yoshinobu; Matsumura, Tsuyoshi; Yasui, Kumiko; Fujimura, Harutoshi; Sakoda, Saburo; Ono, Takahiro

    2014-06-01

    Although dysphagia is a life-threatening problem in patients with Duchenne muscular dystrophy (DMD), the pathophysiology of oral stage dysphagia is yet to be understood. The present study investigated the tongue motor deficit during swallowing in patients with DMD and its relationship with disease-specific palatal morphology. Tongue pressure during swallowing water was recorded in 11 male patients with DMD and 11 age- and sex-matched healthy subjects using an intra-oral sensor with five measuring points, and the state of tongue pressure production was compared between the groups. Palatal morphology was assessed by a non-contact three-dimensional scanner on maxillary plaster models. In patients with DMD, the normal sequential order of tongue-palate contact was lost and the maximal magnitude and integrated value of tongue pressure on the mid-anterior part of palate were smaller than those in healthy subjects. The width of the palate in patients was greater than that in healthy subjects and the depth of the palate in patients had a negative correlation with tongue pressure magnitude on the median palate. Our results suggested that the deteriorated tongue motor kinetics prevented tongue movement during swallowing that was appropriate for the depth of the palate and affects the state of tongue pressure production during swallowing.

  11. Tongue Scrapers Only Slightly Reduce Bad Breath

    Science.gov (United States)

    ... your desktop! more... Tongue Scrapers Only Slightly Reduce Bad Breath Article Chapters Tongue Scrapers Only Slightly Reduce ... oral cavity. Reviewed: January 2012 Related Articles: Halitosis (Bad Breath) Do You Have Traveler's Breath? Does a ...

  12. Biomechanical model of batoid (skates and rays) pectoral fins predicts the influence of skeletal structure on fin kinematics: implications for bio-inspired design.

    Science.gov (United States)

    Russo, R S; Blemker, S S; Fish, F E; Bart-Smith, H

    2015-06-16

    Growing interest in the development of bio-inspired autonomous underwater vehicles (AUVs) has motivated research in understanding the mechanisms behind the propulsion systems of marine animals. For example, the locomotive behavior of rays (Batoidea) by movement of the pectoral fins is of particular interest due to their superior performance characteristics over contemporary AUV propulsion systems. To better understand the mechanics of pectoral fin propulsion, this paper introduces a biomechanical model that simulates how batoid skeletal structures function to achieve the swimming locomotion observed in nature. Two rays were studied, Dasyatis sabina (Atlantic ray), and Rhinoptera bonasus (cownose ray). These species were selected because they exhibit very different swimming styles (undulation versus oscillation), but all use primarily their pectoral fins for propulsion (unlike electric rays or guitarfishes). Computerized tomography scans of each species were taken to image the underlying structure, which reveal a complex system of cartilaginous joints and linkages. Data collected from these images were used to quantify the complete skeletal morphometry of each batoid fin. Morphological differences were identified in the internal cartilage arrangement between each species including variations in the orientation of the skeletal elements, or radials, and the joint patterns between them, called the inter-radial joint pattern. These data were used as the primary input into the biomechanical model to couple a given ray skeletal structure with various swimming motions. A key output of the model is an estimation of the uniaxial strain that develops in the skeletal connective tissue in order for the structure to achieve motions observed during swimming. Tensile load tests of this connective tissue were conducted to further investigate the implications of the material strain predictions. The model also demonstrates that changes in the skeletal architecture (e.g., joint

  13. Tongue Image Feature Extraction in TCM

    Institute of Scientific and Technical Information of China (English)

    LI Dong; DU Lian-xiang; LU Fu-ping; DU Jun-ping

    2004-01-01

    In this paper, digital image processing and computer vision techniques are applied to study tongue images for feature extraction with VC++ and Matlab. Extraction and analysis of the tongue surface features are based on shape, color, edge, and texture. The developed software has various functions and good user interface and is easy to use. Feature data for tongue image pattern recognition is provided, which form a sound basis for the future tongue image recognition.

  14. Ectomesenchymal chondromyxoid tumor of tongue

    Directory of Open Access Journals (Sweden)

    Shan-Yin Tsai

    2012-01-01

    Full Text Available Ectomesenchymal chondromyxoid tumor (ECMT is a rare entity of the dorsal tongue first described in 1995. Herein, we report a rare case of lingual ECMT in a 41-year-old man. Patient presented with an asymptomatic, small nodule (0.5 cm in diameter in the anterior tongue. The pathological findings showed uni-lobular proliferation of fusiform cells, arranged in net-like sheets or swirls, in a chondromyxoid background. The tumor cells were immunoreactive for S-100 and glial fibrillary acidic protein (GFAP, but negative for epithelial markers. Familiarity with this entity helps pathologists make a correct diagnosis.

  15. Mother Tongue Tuition in Sweden--Curriculum Analysis and Classroom Experience

    Science.gov (United States)

    Reath Warren, Anne

    2013-01-01

    The model of Mother Tongue Tuition (MTT) which has developed in Sweden since the 1970's offers speakers of languages other than Swedish the opportunity to request tuition in their mother tongue, from kindergarten through to year 12. It is unique among the major immigrant-receiving countries of the world yet little is known about MTT and its…

  16. Interface Electronic Circuitry for an Electronic Tongue

    Science.gov (United States)

    Keymeulen, Didier; Buehler, Martin

    2007-01-01

    Electronic circuitry has been developed to serve as an interface between an electronic tongue and digital input/output boards in a laptop computer that is used to control the tongue and process its readings. Electronic tongues can be used for a variety of purposes, including evaluating water quality, analyzing biochemicals, analyzing biofilms, and measuring electrical conductivities of soils.

  17. Tongue as the Window to the Heart

    Institute of Scientific and Technical Information of China (English)

    Tsung O.Cheng

    2011-01-01

    @@ To the Editor: I read with great interest your masterful article on study of the tongue in patients with coronary heart disease. Tongue is, indeed, the window to the heart. Many cardiovascular diseases including coronary heart disease can be accurately diagnosed by the Chinese traditional physicians by careful inspection of the tongue (Figure 1).

  18. Influence of loading cycle profile and frequency on a biomechanical parameter of a model of a balloon kyphoplasty-augmented lumbar spine segment: a finite element analysis study.

    Science.gov (United States)

    Li, Yuan; Lewis, Gladius

    2010-01-01

    For patients who are suffering debilitating and persistent pain due to vertebral compression fracture(s) and for whom conservative therapies have not provided relief, balloon kyphoplasty (BKP) is used as a surgical option. There are only a very few literature reports on the use of the finite element analysis (FEA) method to obtain biomechanical parameters of models of spine segments that include BKP augmentation at a given level. In each of these studies, the applied loading used was quasi-static. During normal activities of daily living, the patient's spine would be subject to dynamically-applied loading. Thus, the question of the influence of the characteristics of a dynamically-applied loading cycle on biomechanical parameters of a spine that includes BKP-augmented segment(s) is germane; however, a study of this issue is lacking. We investigated this issue in the present FEA work, with the spine segment model being the L1-L3 motion segment units (MSUs) (a segment that is commonly augmented using BKP) and prophylactic BKP simulated at L2. The dynamic load was the compressive load-versus-time cycle to which the L3-L4 MSU is subjected during gait. Four cases of the cycle were considered, corresponding to slow-, normal-, fast- and very fast-paced gait. The loading cycle was applied to the superior surface of L1 while the inferior surface of L3 was fully constrained. It was found that (1) the global mean von Mises stress during the loading cycle (σVMG), in each tissue in the model increased in going from a slow-paced gait cycle to a very fast-paced gait cycle; and (2) for the slow-paced gait cycle, with increase in frequency of the cycle, f (1 ≤ f ≤ 3 Hz), σVMG in each of these tissues increased. Potential uses of the present findings are identified.

  19. Bio-Mechanical Model of the Brain for a Per-Operative Image-Guided Neuronavigator Compensating for "Brain-Shift" Deformations

    CERN Document Server

    Bucki, Marek; Payan, Yohan

    2007-01-01

    In this paper we present a methodology to address the problem of brain tissue deformation referred to as 'brain-shift'. This deformation occurs throughout a neurosurgery intervention and strongly alters the accuracy of the neuronavigation systems used to date in clinical routine which rely solely on pre-operative patient imaging to locate the surgical target, such as a tumour or a functional area. After a general description of the framework of our intra-operative image-guided system, we describe a procedure to generate patient specific finite element meshes of the brain and propose a biomechanical model which can take into account tissue deformations and surgical procedures that modify the brain structure, like tumour or tissue resection.

  20. Developmental biomechanics of the human cervical spine.

    Science.gov (United States)

    Nuckley, David J; Linders, David R; Ching, Randal P

    2013-04-05

    Head and neck injuries, the leading cause of death for children in the U.S., are difficult to diagnose, treat, and prevent because of a critical void in our understanding of the biomechanical response of the immature cervical spine. The objective of this study was to investigate the functional and failure biomechanics of the cervical spine across multiple axes of loading throughout maturation. A correlational study design was used to examine the relationships governing spinal maturation and biomechanical flexibility curves and tolerance data using a cadaver human in vitro model. Eleven human cadaver cervical spines from across the developmental spectrum (2-28 years) were dissected into segments (C1-C2, C3-C5, and C6-C7) for biomechanical testing. Non-destructive flexibility tests were performed in tension, compression, flexion, extension, lateral bending, and axial rotation. After measuring their intact biomechanical responses, each segment group was failed in different modes to measure the tissue tolerance in tension (C1-C2), compression (C3-C5), and extension (C5-C6). Classical injury patterns were observed in all of the specimens tested. Both the functional (pcervical spine throughout maturation and elucidated age, spinal level, and mode of loading specificity. These data support our understanding of the child cervical spine from a developmental perspective and facilitate the generation of injury prevention or management schema for the mitigation of child spine injuries and their deleterious effects.

  1. Gingival Recessions and Biomechanics

    DEFF Research Database (Denmark)

    Laursen, Morten Godtfredsen

    Gingival recessions and biomechanics “Tissue is the issue, but bone sets the tone.“ A tooth outside the cortical plate can result in loss of bone and development of a gingival recession. The presentation aims to show biomechanical considerations in relation to movement of teeth with gingival...... recessions. Gingival recession is a problem often in the region of the lower incisors. A micro-CT study on human autopsy material, performed at the University of Aarhus, confirmed that the anterior mandibular alveolar envelope is indeed very thin. The prognosis of a gingival recession can be improved...

  2. Does Anticoagulant Medication Alter Fracture-Healing? A Morphological and Biomechanical Evaluation of the Possible Effects of Rivaroxaban and Enoxaparin Using a Rat Closed Fracture Model

    Science.gov (United States)

    Prodinger, Peter Michael; Burgkart, Rainer; Kreutzer, Kilian; Liska, Franz; Pilge, Hakan; Schmitt, Andreas; Knödler, Martina; Holzapfel, Boris Michael; Hapfelmeier, Alexander; Tischer, Thomas; Bissinger, Oliver

    2016-01-01

    Low molecular weight heparin (LMWH) is routinely used to prevent thromboembolism in orthopaedic surgery, especially in the treatment of fractures or after joint-replacement. Impairment of fracture-healing due to increased bone-desorption, delayed remodelling and lower calcification caused by direct osteoclast stimulation is a well-known side effect of unfractioned heparin. However, the effect of LMWH is unclear and controversial. Recent studies strongly suggest impairment of bone-healing in-vitro and in animal models, characterized by a significant decrease in volume and quality of new-formed callus. Since October 2008, Rivaroxaban (Xarelto) is available for prophylactic use in elective knee- and hip-arthroplasty. Recently, some evidence has been found indicating an in vitro dose independent reduction of osteoblast function after Rivaroxaban treatment. In this study, the possible influence of Rivaroxaban and Enoxaparin on bone-healing in vivo was studied using a standardized, closed rodent fracture-model. 70 male Wistar-rats were randomized to Rivaroxaban, Enoxaparin or control groups. After pinning the right femur, a closed, transverse fracture was produced. 21 days later, the animals were sacrificed and both femora harvested. Analysis was done by biomechanical testing (three-point bending) and micro CT. Both investigated substances showed histomorphometric alterations of the newly formed callus assessed by micro CT analysis. In detail the bone (callus) volume was enhanced (sign. for Rivaroxaban) and the density reduced. The bone mineral content was enhanced accordingly (sign. for Rivaroxaban). Trabecular thickness was reduced (sign. for Rivaroxaban). Furthermore, both drugs showed significant enlarged bone (callus) surface and degree of anisotropy. In contrast, the biomechanical properties of the treated bones were equal to controls. To summarize, the morphological alterations of the fracture-callus did not result in functionally relevant deficits. PMID:27455072

  3. Editorial: Mother Tongue and Education

    Directory of Open Access Journals (Sweden)

    S. P. Singh

    2017-01-01

    Full Text Available Linguists, language experts and child-psychologists believe that children can learn better in their mother tongue but that doesn’t go against multilingual education. It has also been observed that children studying through multilingual system develop better thinking and skills than monolingual education systems. Parents and peer all can help the child understand the issues if it

  4. Solitary angiokeratoma of the tongue.

    Science.gov (United States)

    Sion-Vardy, Netta; Manor, Esther; Puterman, Max; Bodner, Lipa

    2008-01-01

    Angiokeratoma is a rare cutaneous lesion. It can be either a generalized systemic form, presenting as multiple asymptomatic papules on the skin, associated with metabolic diseases or a solitary cutaneous form. Oral cavity involvement is more common in the systemic form, as a part of a more generalized cutaneous disease, but very rare in the localized form of angiokeratoma. A 45-year-old female presented with a painless lesion on the tongue of one months duration, which bled occasionally. On clinical examination, a lesion of approximately 5 mm in diameter was observed on the left surface of the tongue. The lesion was purple in color with a granulomatous appearance. There were no other changes in the oral mucosa. On dermatologic examination, no angiokeratomas were found, anywhere on the skin. The lesion was excised under local anesthesia. The histologic diagnosis was angiokeratoma. A case of a solitary angiokeratoma of the tongue is reported. We report here the third intra-oral case and the second case in the tongue with solitary angiokeratoma.

  5. Tongues of Men and Angels

    DEFF Research Database (Denmark)

    McGraw, John J.

    2012-01-01

    The accelerating popularity of Charismatic Christianity has brought with it a host of new sensibilities and ritual practices. Glossolalia, or ‘speaking in tongues,’ stands out among these as a particularly dramatic innovation. Typically staid churchgoers, once touched by the Holy Spirit, begin...

  6. RELEASE OF TONGUE-TIE IN NEONATES

    Directory of Open Access Journals (Sweden)

    V. Raveenthiran

    2012-01-01

    Full Text Available Arguably, release of tongue tie is the oldest surgical procedure and it is perhaps older than circumcision. According to the Old Testament, the Lord released the tied tongue of Moses and made him speak well. Tongue-tie is pedantically known as ankyloglossia inferior minor. Simplicity of its treatment has earned this malady several etiological attributions such as difficulty of speech and breast feeding. All over the world, lactation consultants refer neonates for release of tongue tie as they believe it to be the cause of maternal nipple pain.Perhaps this is the only indication of tongue tie release in neonates.

  7. Exploring the biomechanics of taurodontism

    Science.gov (United States)

    Benazzi, Stefano; Nguyen, Huynh N; Kullmer, Ottmar; Hublin, Jean-Jacques

    2015-01-01

    Taurodontism (i.e. enlarged pulp chamber with concomitant apical displacement of the root bi/trifurcation) is considered a dental anomaly with relatively low incidence in contemporary societies, but it represents a typical trait frequently found in Neandertal teeth. Four hypotheses can be envisioned to explain the high frequency in Neandertals: adaptation to a specific occlusal loading regime (biomechanical advantage), adaptation to a high attrition diet, pleiotropic or genetic drift effects. In this contribution we used finite element analysis (FEA) and advanced loading concepts based on macrowear information to evaluate whether taurodontism supplies some dental biomechanical advantages. Loads were applied to the digital model of the lower right first molar (RM1) of the Neandertal specimen Le Moustier 1, as well as to the digital models of both a shortened and a hyper-taurodontic version of Le Moustier RM1. Moreover, we simulated a scenario where an object is held between teeth and pulled in different directions to investigate whether taurodontism might be useful for para-masticatory activities. Our results do not show any meaningful difference among all the simulations, pointing out that taurodontism does not improve the functional biomechanics of the tooth and does not favour para-masticatory pulling activities. Therefore, taurodontism should be considered either an adaptation to a high attrition diet or most likely the result of pleiotropic or genetic drift effects. Finally, our results have important implications for modern dentistry during endodontic treatments, as we observed that filling the pulp chamber with dentine-like material increases tooth stiffness, and ultimately tensile stresses in the crown, thus favouring tooth failure. PMID:25407030

  8. Outrun or Outmaneuver: Predator-Prey Interactions as a Model System for Integrating Biomechanical Studies in a Broader Ecological and Evolutionary Context.

    Science.gov (United States)

    Moore, Talia Y; Biewener, Andrew A

    2015-12-01

    Behavioral studies performed in natural habitats provide a context for the development of hypotheses and the design of experiments relevant both to biomechanics and to evolution. In particular, predator-prey interactions are a model system for integrative study because success or failure of predation has a direct effect on fitness and drives the evolution of specialized performance in both predator and prey. Although all predators share the goal of capturing prey, and all prey share the goal of survival, the behavior of predators and prey are diverse in nature. This article presents studies of some predator-prey interactions sharing common predation strategies that reveal general principles governing the behaviors of predator and prey, even in distantly related taxa. Studies of predator-prey interactions also reveal that maximal performance observed in a laboratory setting is not necessarily the performance that determines fitness. Thus, considering locomotion in the context of predation ecology can aid in evolutionarily relevant experimental design. Classification by strategy reveals that displaying unpredictable trajectories is a relevant anti-predator behavior in response to multiple predation strategies. A predator's perception and pursuit of prey can be affected indirectly by divergent locomotion of similar animals that share an ecosystem. Variation in speed and direction of locomotion that directly increases the unpredictability of a prey's trajectory can be increased through genetic mutation that affects locomotor patterns, musculoskeletal changes that affect maneuverability, and physical interactions between an animal and the environment. By considering the interconnectedness of ecology, physical constraints, and the evolutionary history of behavior, studies in biomechanics can be designed to inform each of these fields.

  9. Mathematical foundations of biomechanics.

    Science.gov (United States)

    Niederer, Peter F

    2010-01-01

    The aim of biomechanics is the analysis of the structure and function of humans, animals, and plants by means of the methods of mechanics. Its foundations are in particular embedded in mathematics, physics, and informatics. Due to the inherent multidisciplinary character deriving from its aim, biomechanics has numerous connections and overlapping areas with biology, biochemistry, physiology, and pathophysiology, along with clinical medicine, so its range is enormously wide. This treatise is mainly meant to serve as an introduction and overview for readers and students who intend to acquire a basic understanding of the mathematical principles and mechanics that constitute the foundation of biomechanics; accordingly, its contents are limited to basic theoretical principles of general validity and long-range significance. Selected examples are included that are representative for the problems treated in biomechanics. Although ultimate mathematical generality is not in the foreground, an attempt is made to derive the theory from basic principles. A concise and systematic formulation is thereby intended with the aim that the reader is provided with a working knowledge. It is assumed that he or she is familiar with the principles of calculus, vector analysis, and linear algebra.

  10. Biomechanics of foetal movement.

    Science.gov (United States)

    Nowlan, N C

    2015-01-02

    Foetal movements commence at seven weeks of gestation, with the foetal movement repertoire including twitches, whole body movements, stretches, isolated limb movements, breathing movements, head and neck movements, jaw movements (including yawning, sucking and swallowing) and hiccups by ten weeks of gestational age. There are two key biomechanical aspects to gross foetal movements; the first being that the foetus moves in a dynamically changing constrained physical environment in which the freedom to move becomes increasingly restricted with increasing foetal size and decreasing amniotic fluid. Therefore, the mechanical environment experienced by the foetus affects its ability to move freely. Secondly, the mechanical forces induced by foetal movements are crucial for normal skeletal development, as evidenced by a number of conditions and syndromes for which reduced or abnormal foetal movements are implicated, such as developmental dysplasia of the hip, arthrogryposis and foetal akinesia deformation sequence. This review examines both the biomechanical effects of the physical environment on foetal movements through discussion of intrauterine factors, such as space, foetal positioning and volume of amniotic fluid, and the biomechanical role of gross foetal movements in human skeletal development through investigation of the effects of abnormal movement on the bones and joints. This review also highlights computational simulations of foetal movements that attempt to determine the mechanical forces acting on the foetus as it moves. Finally, avenues for future research into foetal movement biomechanics are highlighted, which have potential impact for a diverse range of fields including foetal medicine, musculoskeletal disorders and tissue engineering.

  11. Biomechanics of foetal movement

    Directory of Open Access Journals (Sweden)

    N.C. Nowlan

    2015-01-01

    Full Text Available Foetal movements commence at seven weeks of gestation, with the foetal movement repertoire including twitches, whole body movements, stretches, isolated limb movements, breathing movements, head and neck movements, jaw movements (including yawning, sucking and swallowing and hiccups by ten weeks of gestational age. There are two key biomechanical aspects to gross foetal movements; the first being that the foetus moves in a dynamically changing constrained physical environment in which the freedom to move becomes increasingly restricted with increasing foetal size and decreasing amniotic fluid. Therefore, the mechanical environment experienced by the foetus affects its ability to move freely. Secondly, the mechanical forces induced by foetal movements are crucial for normal skeletal development, as evidenced by a number of conditions and syndromes for which reduced or abnormal foetal movements are implicated, such as developmental dysplasia of the hip, arthrogryposis and foetal akinesia deformation sequence. This review examines both the biomechanical effects of the physical environment on foetal movements through discussion of intrauterine factors, such as space, foetal positioning and volume of amniotic fluid, and the biomechanical role of gross foetal movements in human skeletal development through investigation of the effects of abnormal movement on the bones and joints. This review also highlights computational simulations of foetal movements that attempt to determine the mechanical forces acting on the foetus as it moves. Finally, avenues for future research into foetal movement biomechanics are highlighted, which have potential impact for a diverse range of fields including foetal medicine, musculoskeletal disorders and tissue engineering.

  12. Biomechanical Comparison of Two Kinds of Internal Fixation in a Type C Zone Ⅱ Pelvic Fracture Model

    Institute of Scientific and Technical Information of China (English)

    Tao Wu; Wei Chen; Qi Zhang; Zhan-Le Zheng; Hong-Zhi Lyu; Yun-Wei Cui; Xiao-Dong Cheng

    2015-01-01

    Background:Unstable pelvic fractures are complex and serious injuries.Selection of a fixation method for these fractures remains a challenging problem for orthopedic surgeons.This study aimed to compare the stability of Tile C pelvic fractures fixed with two iliosacral (IS) screws and minimally invasive adjustable plate (MIAP) combined with one IS screw.Methods:This study was a biomechanical experiment.Six embalmed specimens of the adult pelvis were used.The soft tissue was removed from the specimens,and the spines from the fourth lumbar vertebra to the proximal one-third of both femurs were retained.The pubic symphysis,bilateral sacroiliac joints and ligaments,bilateral hip joints,bilateral sacrotuberous ligaments,and bilateral sacrospinous ligaments were intact.Tile C pelvic fractures were made on the specimens.The symphysis pubis was fixed with a plate,and the fracture on the posterior pelvic ring was fixed with two kinds of internal fixation in turn.The specimens were placed in a biomechanical machine at a standing neutral posture.A cyclic vertical load of up to 500 N was applied,and displacement was recorded.Shifts in the fracture gap were measured by a grating displacement sensor.Statistical analysis used:Paired-samples t-test.Results:Under the vertical load of 100,200,300,400,and 500 N,the average displacement of the specimens fixed with MIAP combined with one IS screw was 0.46,0.735,1.377,1.823,and 2.215 mm,respectively,which was significantly lower than that of specimens fixed with two IS screws under corresponding load (P < 0.05).Under the vertical load of 500 N,the shift in the fracture gap of specimens fixed with MIAP combined with one IS screw was 0.261 ± 0.095 mm,and that of specimens fixed with two IS screws was 0.809 ± 0.170 mm.The difference was significant (P < 0.05).Conclusion:The stability of Tile C pelvic fractures fixed with MIAP combined with one IS screw was better than that fixed with two IS screws.

  13. Surface driven biomechanical breast image registration

    Science.gov (United States)

    Eiben, Björn; Vavourakis, Vasileios; Hipwell, John H.; Kabus, Sven; Lorenz, Cristian; Buelow, Thomas; Williams, Norman R.; Keshtgar, M.; Hawkes, David J.

    2016-03-01

    Biomechanical modelling enables large deformation simulations of breast tissues under different loading conditions to be performed. Such simulations can be utilised to transform prone Magnetic Resonance (MR) images into a different patient position, such as upright or supine. We present a novel integration of biomechanical modelling with a surface registration algorithm which optimises the unknown material parameters of a biomechanical model and performs a subsequent regularised surface alignment. This allows deformations induced by effects other than gravity, such as those due to contact of the breast and MR coil, to be reversed. Correction displacements are applied to the biomechanical model enabling transformation of the original pre-surgical images to the corresponding target position. The algorithm is evaluated for the prone-to-supine case using prone MR images and the skin outline of supine Computed Tomography (CT) scans for three patients. A mean target registration error (TRE) of 10:9 mm for internal structures is achieved. For the prone-to-upright scenario, an optical 3D surface scan of one patient is used as a registration target and the nipple distances after alignment between the transformed MRI and the surface are 10:1 mm and 6:3 mm respectively.

  14. Biomechanics: an integral part of sport science and sport medicine.

    Science.gov (United States)

    Elliott, B

    1999-12-01

    Biomechanics is one of the disciplines in the field of Human Movement and Exercise Science and it can be divided into three broad categories from a research perspective. Clinical biomechanics involves research in the areas of gait, neuromuscular control, tissue mechanics, and movement evaluation during rehabilitation from either injury or disease. Occupational biomechanics typically involves research in the areas of ergonomics and human growth or morphology as they influence movement. While these two categories will briefly be discussed, the primary aim of this paper is to show the role of biomechanics in sports science and sports medicine. Research in sports biomechanics may take the form of describing movement from a performance enhancement (such as matching of impulse curves in rowing) or injury reduction perspective (such as diving in swimming or the assessment of knee joint loading during downhill walking). However, the strength of sports biomechanics research is the ability to establish an understanding of causal mechanisms for selected movements (such as the role of internal rotation of the upper arm in hitting or striking, and the influence of elastic energy and muscle pre-stretch in stretch-shorten-cycle actions). The growth of modelling and computer simulation has further enhanced the potential use of sports biomechanics research (such as quantification of knee joint ligament forces from a dynamic model and optimising gymnastics performance through simulation of in-flight movements). Biomechanics research may also play an integral role in reducing the incidence and severity of sporting injuries (such as identification of the causes of back injuries in cricket, and the causes of knee joint injuries in sport). In the following discussion no attempt will be made to reference all papers published in each of these areas because of the enormity of the task. Published and current work from the biomechanics laboratory at the Department of Human Movement and

  15. The polycomb group protein EZH2 is a novel therapeutic target in tongue cancer.

    Science.gov (United States)

    Li, Zhongwu; Wang, Yanling; Qiu, Jing; Li, Qiang; Yuan, Chunping; Zhang, Wei; Wang, Dongmiao; Ye, Jinhai; Jiang, Hongbin; Yang, Jianrong; Cheng, Jie

    2013-12-01

    EZH2, a core member of the Polycomb Repressor Complex 2 (PRC2), mediates transcriptional silencing by catalyzing the trimethylation of histone 3 lysine 27 (H3K27), which plays key roles in cancer initiation and progression. Here, we investigated the expression pattern and biological roles of EZH2 in tongue tumorigenesis by loss-of-function assays using small interference RNA and EZH2 inhibitor DZNep. Also we determined the therapeutic efficiency of DZNep against tongue cancer in vivo. We found that aberrantly overexpressed EZH2 was associated with pathological grade, cervical nodes metastasis and Ki-67 expression in tongue cancers. Elevated EZH2 correlated with shorter overall survival and showed significant and independent prognostic importance in patients with tongue cancer. Both genetic and pharmacological depletion of EZH2 inhibited cell proliferation, migration, invasion and colony formation and decreased CD44+ subpopulation probably in part through modulating p16, p21 and E-caherin. Moreover, DZNep enhanced the anticancer effects of 5-Fluorouracil. Furthermore, intratumoral EZH2 inhibition induced by DZNep intraperitoneal administration significantly attenuated tumor growth in a tongue cancer xenograft model. Taken together, our results indicate that EZH2 serves as a key driver with multiple oncogenic functions during tongue tumorigenesis and a new biomarker for tongue cancer diagnosis and prognostic prediction. These findings open up possibilities for therapeutic intervention against EZH2 in tongue cancer.

  16. Artificial tongue based on metal-biomolecule coordination polymer nanoparticles.

    Science.gov (United States)

    Pu, Fang; Ran, Xiang; Ren, Jinsong; Qu, Xiaogang

    2016-02-25

    We construct an array-based recognition system (the so-called artificial tongue) through the self-assembly of nucleotides, dyes and lanthanide ions. Metal ions are selected as model analytes for verifying its discrimination ability. The work provides valuable insights into the application and development of biomolecule-based materials.

  17. Dislocated Tongue Muscle Attachment and Cleft Palate Formation.

    Science.gov (United States)

    Kouskoura, T; El Fersioui, Y; Angelini, M; Graf, D; Katsaros, C; Chiquet, M

    2016-04-01

    In Pierre Robin sequence, a retracted tongue due to micrognathia is thought to physically obstruct palatal shelf elevation and thereby cause cleft palate. However, micrognathia is not always associated with palatal clefting. Here, by using the Bmp7-null mouse model presenting with cleft palate and severe micrognathia, we provide the first causative mechanism linking the two. In wild-type embryos, the genioglossus muscle, which mediates tongue protrusion, originates from the rostral process of Meckel's cartilage and later from the mandibular symphysis, with 2 tendons positive for Scleraxis messenger RNA. In E13.5 Bmp7-null embryos, a rostral process failed to form, and a mandibular symphysis was absent at E17.5. Consequently, the genioglossus muscle fibers were diverted toward the lingual surface of Meckel's cartilage and mandibles, where they attached in an aponeurosis that ectopically expressed Scleraxis. The deflection of genioglossus fibers from the anterior-posterior toward the medial-lateral axis alters their direction of contraction and necessarily compromises tongue protrusion. Since this muscle abnormality precedes palatal shelf elevation, it is likely to contribute to clefting. In contrast, embryos with a cranial mesenchyme-specific deletion of Bmp7 (Bmp7:Wnt1-Cre) exhibited some degree of micrognathia but no cleft palate. In these embryos, a rostral process was present, indicating that mesenchyme-derived Bmp7 is dispensable for its formation. Moreover, the genioglossus appeared normal in Bmp7:Wnt1-Cre embryos, further supporting a role of aberrant tongue muscle attachment in palatal clefting. We thus propose that in Pierre Robin sequence, palatal shelf elevation is not impaired simply by physical obstruction by the tongue but by a specific developmental defect that leads to functional changes in tongue movements.

  18. Morphological and Biomechanical Differences in the Elastase and AngII apoE−/− Rodent Models of Abdominal Aortic Aneurysms

    Directory of Open Access Journals (Sweden)

    Evan H. Phillips

    2015-01-01

    Full Text Available An abdominal aortic aneurysm (AAA is a potentially fatal cardiovascular disease with multifactorial development and progression. Two preclinical models of the disease (elastase perfusion and angiotensin II infusion in apolipoprotein-E-deficient animals have been developed to study the disease during its initiation and progression. To date, most studies have used ex vivo methods to examine disease characteristics such as expanded aortic diameter or analytic methods to look at circulating biomarkers. Herein, we provide evidence from in vivo ultrasound studies of the temporal changes occurring in biomechanical parameters and macromolecules of the aortic wall in each model. We present findings from 28-day studies in elastase-perfused rats and AngII apoE−/− mice. While each model develops AAAs specific to their induction method, they both share characteristics with human aneurysms, such as marked changes in vessel strain and blood flow velocity. Histology and nonlinear microscopy confirmed that both elastin and collagen, both important extracellular matrix molecules, are similarly affected in their levels and spatial distribution. Future studies could make use of the differences between these models in order to investigate mechanisms of disease progression or evaluate potential AAA treatments.

  19. Ossifying chondrolipoma of the tongue

    Directory of Open Access Journals (Sweden)

    Tasić Desanka

    2012-01-01

    Full Text Available Introduction. Chondrolipomas and osteolipomas are uncommon variants of lipomatous tumors. Case report. We presented a 60-year-old woman with ossifying chondrolipoma of the tongue. Clinical examination revealed a firm nodular mass, located in the midline of the posterior region on the dorsal surface of the tongue. Histologically, the lesion was well-delimited showing areas of mature adipocytes arranged in lobules and separated by fibrous connective tissue septa, islands of mature cartilaginous tissue and osseous metaplasia. Trabeculae of lamellar bone within a fibro-fatty background were visible throughout the tumor. The cartilaginous areas merging centrally with bone formation and fatty marrow tissue were present, as well as the hematopoietic elements in the fatty marrow. The bone forming was found to be through both membranous and enchondral mechanisms. Conclusion. Ossifying chrondrolipoma with hematopoietic elements is extremely unusual lesion. This interesting entity should be kept in mind in the differential diagnosis of lingual lesions.

  20. Linezolid induced black hairy tongue

    Directory of Open Access Journals (Sweden)

    Govindan Balaji

    2014-01-01

    Full Text Available Black hairy tongue (BHT also called as lingua villosa nigra, is a self limiting benign condition characterized by hypertrophy and elongation of filiform papillae of tongue with brown or black discoloration. Smoking, poor oral hygiene, xerostomia, using peroxide containing mouth washes, substance abuse and drugs (steroids, methyldopa, olanzapine, etc are the predisposing factors. However its occurrence in relation to linezolid ingestion among south Indians has not been reported in PubMed database. Here we report a case, where significant association of linezolid intake with BHT was found in a 10-year-old boy, who was treated with tablet linezolid for post surgical infection of left side radial neck fracture. This case is reported for the rarity of occurrence with linezolid therapy. According to Naranjo adverse drug reaction (ADR causality scale, the association of BHT due to linezolid in our case was probable.

  1. 9 CFR 319.103 - Cured beef tongue.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Cured beef tongue. 319.103 Section 319... Cured beef tongue. In preparing “Cured Beef Tongue,” the application of curing solution to the fresh beef tongue shall not result in an increase in the weight of the cured beef tongue of more than...

  2. On seed physiology, biomechanics and plant phenology in Eragrostis tef

    NARCIS (Netherlands)

    Delden, van S.H.

    2011-01-01

    • Key words: Teff (Eragrostis tef (Zuccagni) Trotter), germination, temperature, model, leaf appearance, phyllochron, development rate, lodging, biomechanics, safety factor, flowering, heading, day length, photoperiod. • Background Teff (Eragrostis tef (Zuccagni) Trotter) is a C4 annual g

  3. Somatosensory processing of the tongue in humans

    Directory of Open Access Journals (Sweden)

    Kiwako Sakamoto

    2010-11-01

    Full Text Available We review research on somatosensory (tactile processing of the tongue based on data obtained using non-invasive neurophysiological and neuroimaging methods. Technical difficulties in stimulating the tongue, due to the noise elicited by the stimulator, the fixation of the stimulator, and the vomiting reflex, have necessitated the development of specialized devices. In this article, we show the brain activity relating to somatosensory processing of the tongue evoked by such devices. More recently, the postero-lateral part of the tongue has been stimulated, and the brain response compared with that on stimulation of the antero-lateral part of the tongue. It is likely that a difference existed in somatosensory processing of the tongue, particularly around primary somatosensory cortex (SI, Brodmann area 40 (BA 40, and the anterior cingulate cortex (ACC.

  4. Tongue Color Analysis for Medical Application

    Directory of Open Access Journals (Sweden)

    Bob Zhang

    2013-01-01

    Full Text Available An in-depth systematic tongue color analysis system for medical applications is proposed. Using the tongue color gamut, tongue foreground pixels are first extracted and assigned to one of 12 colors representing this gamut. The ratio of each color for the entire image is calculated and forms a tongue color feature vector. Experimenting on a large dataset consisting of 143 Healthy and 902 Disease (13 groups of more than 10 samples and one miscellaneous group, a given tongue sample can be classified into one of these two classes with an average accuracy of 91.99%. Further testing showed that Disease samples can be split into three clusters, and within each cluster most if not all the illnesses are distinguished from one another. In total 11 illnesses have a classification rate greater than 70%. This demonstrates a relationship between the state of the human body and its tongue color.

  5. Relative contributions of strain-dependent permeability and fixed charged density of proteoglycans in predicting cervical disc biomechanics: a poroelastic C5-C6 finite element model study.

    Science.gov (United States)

    Hussain, Mozammil; Natarajan, Raghu N; Chaudhary, Gulafsha; An, Howard S; Andersson, Gunnar B J

    2011-05-01

    Disc swelling pressure (P(swell)) facilitated by fixed charged density (FCD) of proteoglycans (P(fcd)) and strain-dependent permeability (P(strain)) are of critical significance in the physiological functioning of discs. FCD of proteoglycans prevents any excessive matrix deformation by tissue stiffening, whereas strain-dependent permeability limits the rate of stress transfer from fluid to solid skeleton. To date, studies involving the modeling of FCD of proteoglycans and strain-dependent permeability have not been reported for the cervical discs. The current study objective is to compare the relative contributions of strain-dependent permeability and FCD of proteoglycans in predicting cervical disc biomechanics. Three-dimensional finite element models of a C5-C6 segment with three different disc compositions were analyzed: an SPFP model (strain-dependent permeability and FCD of proteoglycans), an SP model (strain-dependent permeability alone), and an FP model (FCD of proteoglycans alone). The outcomes of the current study suggest that the relative contributions of strain-dependent permeability and FCD of proteoglycans were almost comparable in predicting the physiological behavior of the cervical discs under moment loads. However, under compression, strain-dependent permeability better predicted the in vivo disc response than that of the FCD of proteoglycans. Unlike the FP model (least stiff) in compression, motion behavior of the three models did not vary much from each other and agreed well within the standard deviations of the corresponding in vivo published data. Flexion was recorded with maximum P(fcd) and P(strain), whereas minimum values were found in extension. The study data enhance the understanding of the roles played by the FCD of proteoglycans and strain-dependent permeability and porosity in determining disc tissue swelling behavior. Degenerative changes involving strain-dependent permeability and/or loss of FCD of proteoglycans can further be

  6. Biomechanical analysis of the main masticatory muscles in the rabbit.

    Science.gov (United States)

    Baron, P; Debussy, T

    1980-09-01

    The main masticatory muscles of the Rabbit (Oryctolagus cuniculus L.) were divided into their 25 component bundles per side. 5 dry skulls were used to determine points of origin and insertion which were then projected onto 3 planes perpendicular to each other, for the establishment of a biomechanical model. By interpreting this model and by examining various mandibular movements, the bundles were classified into 16 functional groups. The findings of other biomechanical studies are contrasted with the results of the study.

  7. Giant Plexiform Schwannoma of the Tongue

    Directory of Open Access Journals (Sweden)

    Lluís Nisa

    2011-01-01

    Full Text Available We present the case of a 38-year-old woman that presented with a very slowly enlarging mass of the tongue. MRI revealed a large mass originating in the tongue base and extending to the supraglottic space. Biopsy of this tumor confirmed the diagnosis of schwannoma. An endaural approach allowed complete resection of the tumor. Definitive histopathological examination showed a plexiform schwannoma. Schwannoma or neurilemoma represents a benign tumor potentially affecting any nerve. The head and neck region is a relatively common location for schwannomas, but tongue schwannomas are considered to be rare and pose the problem of both clinical and histological differential diagnosis of tongue masses.

  8. Base of tongue schwannoma: a case report.

    Science.gov (United States)

    Ying, Yu-Lan Mary; Zimmer, Lee A; Myers, Eugene N

    2006-07-01

    Both malignant and benign lesions may be found on the base of the tongue, including metastasis from other sites. Various surgical approaches to the base of tongue have been described. Here, we report a case of a 26-year-old woman with a schwannoma in the base of tongue removed through a suprahyoid pharyngotomy approach. The biology and pathology of schwannoma in the oral cavity are discussed. The advantage of the suprahyoid pharyngotomy approach for complete excision of a mass in the base of tongue is demonstrated.

  9. Giant plexiform schwannoma of the tongue.

    Science.gov (United States)

    Nisa, Lluís; von Büren, Toni; Tiab, Amine; Giger, Roland

    2011-01-01

    We present the case of a 38-year-old woman that presented with a very slowly enlarging mass of the tongue. MRI revealed a large mass originating in the tongue base and extending to the supraglottic space. Biopsy of this tumor confirmed the diagnosis of schwannoma. An endaural approach allowed complete resection of the tumor. Definitive histopathological examination showed a plexiform schwannoma. Schwannoma or neurilemoma represents a benign tumor potentially affecting any nerve. The head and neck region is a relatively common location for schwannomas, but tongue schwannomas are considered to be rare and pose the problem of both clinical and histological differential diagnosis of tongue masses.

  10. Tongue Strength: Its Relationship to Tongue Thrusting, Open-Bite, and Articulatory Proficiency.

    Science.gov (United States)

    Dworkin, James P.; Culatta, Richard A.

    1980-01-01

    No significant differences in tongue strength were found between any of the three groups of 7- to 16-year old children: normal speaking with anterior tongue thrusting during swallow and open bite malocclusion, frontal lisping with anterior tongue thrusting during swallow and open bite malocclusion, and normal controls. (Author/DLS)

  11. Effectiveness of mechanical tongue cleaning on breath odour and tongue coating : a systematic review

    NARCIS (Netherlands)

    Van der Sleen, M. I.; Slot, D. E.; Van Trijffel, E.; Winkel, E. G.; Van der Weijden, G. A.

    2010-01-01

    Background: The objective of this review was to summarize the available evidence regarding the effects of mechanical tongue cleaning compared with no mechanical tongue cleaning on breath odour and tongue coating (TC). Methods: PubMed-MEDLINE, EMBASE and Cochrane-CENTRAL were searched to identify pot

  12. Effectiveness of mechanical tongue cleaning on breath odour and tongue coating: a systematic review

    NARCIS (Netherlands)

    M.I. van der Sleen; D.E. Slot; E. van Trijffel; E.G. Winkel; G.A. van der Weijden

    2010-01-01

    Background:  The objective of this review was to summarize the available evidence regarding the effects of mechanical tongue cleaning compared with no mechanical tongue cleaning on breath odour and tongue coating (TC). Methods:  PubMed-MEDLINE, EMBASE and Cochrane-CENTRAL were searched to identify p

  13. Biomechanics of Pediatric Manual Wheelchair Mobility.

    Science.gov (United States)

    Slavens, Brooke A; Schnorenberg, Alyssa J; Aurit, Christine M; Tarima, Sergey; Vogel, Lawrence C; Harris, Gerald F

    2015-01-01

    Currently, there is limited research of the biomechanics of pediatric manual wheelchair mobility. Specifically, the biomechanics of functional tasks and their relationship to joint pain and health is not well understood. To contribute to this knowledge gap, a quantitative rehabilitation approach was applied for characterizing upper extremity biomechanics of manual wheelchair mobility in children and adolescents during propulsion, starting, and stopping tasks. A Vicon motion analysis system captured movement, while a SmartWheel simultaneously collected three-dimensional forces and moments occurring at the handrim. A custom pediatric inverse dynamics model was used to evaluate three-dimensional upper extremity joint motions, forces, and moments of 14 children with spinal cord injury (SCI) during the functional tasks. Additionally, pain and health-related quality of life outcomes were assessed. This research found that joint demands are significantly different amongst functional tasks, with greatest demands placed on the shoulder during the starting task. Propulsion was significantly different from starting and stopping at all joints. We identified multiple stroke patterns used by the children, some of which are not standard in adults. One subject reported average daily pain, which was minimal. Lower than normal physical health and higher than normal mental health was found in this population. It can be concluded that functional tasks should be considered in addition to propulsion for rehabilitation and SCI treatment planning. This research provides wheelchair users and clinicians with a comprehensive, biomechanical, mobility assessment approach for wheelchair prescription, training, and long-term care of children with SCI.

  14. Biomechanics of Pediatric Manual Wheelchair Mobility

    Science.gov (United States)

    Slavens, Brooke A.; Schnorenberg, Alyssa J.; Aurit, Christine M.; Tarima, Sergey; Vogel, Lawrence C.; Harris, Gerald F.

    2015-01-01

    Currently, there is limited research of the biomechanics of pediatric manual wheelchair mobility. Specifically, the biomechanics of functional tasks and their relationship to joint pain and health is not well understood. To contribute to this knowledge gap, a quantitative rehabilitation approach was applied for characterizing upper extremity biomechanics of manual wheelchair mobility in children and adolescents during propulsion, starting, and stopping tasks. A Vicon motion analysis system captured movement, while a SmartWheel simultaneously collected three-dimensional forces and moments occurring at the handrim. A custom pediatric inverse dynamics model was used to evaluate three-dimensional upper extremity joint motions, forces, and moments of 14 children with spinal cord injury (SCI) during the functional tasks. Additionally, pain and health-related quality of life outcomes were assessed. This research found that joint demands are significantly different amongst functional tasks, with greatest demands placed on the shoulder during the starting task. Propulsion was significantly different from starting and stopping at all joints. We identified multiple stroke patterns used by the children, some of which are not standard in adults. One subject reported average daily pain, which was minimal. Lower than normal physical health and higher than normal mental health was found in this population. It can be concluded that functional tasks should be considered in addition to propulsion for rehabilitation and SCI treatment planning. This research provides wheelchair users and clinicians with a comprehensive, biomechanical, mobility assessment approach for wheelchair prescription, training, and long-term care of children with SCI. PMID:26442251

  15. Teaching undergraduate biomechanics with Just-in-Time Teaching.

    Science.gov (United States)

    Riskowski, Jody L

    2015-06-01

    Biomechanics education is a vital component of kinesiology, sports medicine, and physical education, as well as for many biomedical engineering and bioengineering undergraduate programmes. Little research exists regarding effective teaching strategies for biomechanics. However, prior work suggests that student learning in undergraduate physics courses has been aided by using the Just-in-Time Teaching (JiTT). As physics understanding plays a role in biomechanics understanding, the purpose of study was to evaluate the use of a JiTT framework in an undergraduate biomechanics course. This two-year action-based research study evaluated three JiTT frameworks: (1) no JiTT; (2) mathematics-based JiTT; and (3) concept-based JiTT. A pre- and post-course assessment of student learning used the biomechanics concept inventory and a biomechanics concept map. A general linear model assessed differences between the course assessments by JiTT framework in order to evaluate learning and teaching effectiveness. The results indicated significantly higher learning gains and better conceptual understanding in a concept-based JiTT course, relative to a mathematics-based JiTT or no JiTT course structure. These results suggest that a course structure involving concept-based questions using a JiTT strategy may be an effective method for engaging undergraduate students and promoting learning in biomechanics courses.

  16. Frog tongue acts as muscle-powered adhesive tape

    OpenAIRE

    Kleinteich, Thomas; Gorb, Stanislav N

    2015-01-01

    Frogs are well known to capture fast-moving prey by flicking their sticky tongues out of the mouth. This tongue projection behaviour happens extremely fast which makes frog tongues a biological high-speed adhesive system. The processes at the interface between tongue and prey, and thus the mechanism of adhesion, however, are completely unknown. Here, we captured the contact mechanics of frog tongues by filming tongue adhesion at 2000 frames per second through an illuminated glass. We found th...

  17. Non-rigid registration of a 3D ultrasound and a MR image data set of the female pelvic floor using a biomechanical model

    Directory of Open Access Journals (Sweden)

    Rexilius Jan

    2005-03-01

    Full Text Available Abstract Background The visual combination of different modalities is essential for many medical imaging applications in the field of Computer-Assisted medical Diagnosis (CAD to enhance the clinical information content. Clinically, incontinence is a diagnosis with high clinical prevalence and morbidity rate. The search for a method to identify risk patients and to control the success of operations is still a challenging task. The conjunction of magnetic resonance (MR and 3D ultrasound (US image data sets could lead to a new clinical visual representation of the morphology as we show with corresponding data sets of the female anal canal with this paper. Methods We present a feasibility study for a non-rigid registration technique based on a biomechanical model for MR and US image data sets of the female anal canal as a base for a new innovative clinical visual representation. Results It is shown in this case study that the internal and external sphincter region could be registered elastically and the registration partially corrects the compression induced by the ultrasound transducer, so the MR data set showing the native anatomy is used as a frame for the US data set showing the same region with higher resolution but distorted by the transducer Conclusion The morphology is of special interest in the assessment of anal incontinence and the non-rigid registration of normal clinical MR and US image data sets is a new field of the adaptation of this method incorporating the advantages of both technologies.

  18. A Bayesian approach to distinguishing interdigitated tongue muscles from limited diffusion magnetic resonance imaging.

    Science.gov (United States)

    Ye, Chuyang; Murano, Emi; Stone, Maureen; Prince, Jerry L

    2015-10-01

    The tongue is a critical organ for a variety of functions, including swallowing, respiration, and speech. It contains intrinsic and extrinsic muscles that play an important role in changing its shape and position. Diffusion tensor imaging (DTI) has been used to reconstruct tongue muscle fiber tracts. However, previous studies have been unable to reconstruct the crossing fibers that occur where the tongue muscles interdigitate, which is a large percentage of the tongue volume. To resolve crossing fibers, multi-tensor models on DTI and more advanced imaging modalities, such as high angular resolution diffusion imaging (HARDI) and diffusion spectrum imaging (DSI), have been proposed. However, because of the involuntary nature of swallowing, there is insufficient time to acquire a sufficient number of diffusion gradient directions to resolve crossing fibers while the in vivo tongue is in a fixed position. In this work, we address the challenge of distinguishing interdigitated tongue muscles from limited diffusion magnetic resonance imaging by using a multi-tensor model with a fixed tensor basis and incorporating prior directional knowledge. The prior directional knowledge provides information on likely fiber directions at each voxel, and is computed with anatomical knowledge of tongue muscles. The fiber directions are estimated within a maximum a posteriori (MAP) framework, and the resulting objective function is solved using a noise-aware weighted ℓ1-norm minimization algorithm. Experiments were performed on a digital crossing phantom and in vivo tongue diffusion data including three control subjects and four patients with glossectomies. On the digital phantom, effects of parameters, noise, and prior direction accuracy were studied, and parameter settings for real data were determined. The results on the in vivo data demonstrate that the proposed method is able to resolve interdigitated tongue muscles with limited gradient directions. The distributions of the

  19. Tongue's substance and coating recognition analysis using HSV color threshold in tongue diagnosis

    Science.gov (United States)

    Kamarudin, Nur Diyana; Ooi, Chia Yee; Kawanabe, Tadaaki; Mi, Xiaoyu

    2016-07-01

    In ISO TC249 conference, tongue diagnosis has been one of the most active research and their objectifications has become significant with the help of numerous statistical and machine learning algorithm. Color information of substance or tongue body has kept valuable information regarding the state of disease and its correlation with the internal organs. In order to produce high reproducibility of color measurement analysis, tongue images have to undergo several procedures such as color correction, segmentation and tongue's substance-coating separation. This paper presents a novel method to recognize substance and coating from tongue images and eliminate the tongue coating for accurate substance color measurement for diagnosis. By utilizing Hue, Saturation, Value (HSV) color space, new color-brightness threshold parameters have been devised to improve the efficiency of tongue's substance and coating separation procedures and eliminate shadows. The algorithm offers fast processing time around 0.98 seconds for 60,000 pixels tongue image. The successful tongue's substance and coating separation rate reported is 90% compared to the labelled data verified by the practitioners. Using 300 tongue images, the substance Lab color measurement with small standard deviation had revealed the effectiveness of this proposed method in computerized tongue diagnosis system.

  20. Tongue force in patients with myasthenia gravis

    NARCIS (Netherlands)

    Weijnen, FG; Kuks, JBM; van der Glas, HW; Wassenberg, MWM; Bosman, F

    2000-01-01

    Objectives - The aim was to study tongue force in patients with bulbar myasthenia gravis and compare it with that of patients with ocular myasthenia gravis, patients in clinical remission who previously suffered from bulbar myasthenia gravis, and healthy subjects. Material and methods - Tongue force

  1. Looking Mother Tongue Instruction through Different Perspectives

    Science.gov (United States)

    Regmi, Kapil Dev

    2008-01-01

    Mother Tongue Instruction has been a debatable issue since long. There may be two options in the medium of instruction: either to teach especially primary and preprimary schoolchildren in their own mother tongue or continue using second or foreign language as the medium of instruction. Both of the approaches bear some pros and cons. This article…

  2. A Brief Analysis on Slips of Tongue

    Institute of Scientific and Technical Information of China (English)

    孟庆瑜

    2015-01-01

    The phenomenon of slips of tongue is very common in our daily life.And it is closely related to some psychological reasons.This paper aims to introduce the research about this phenomenon, to present the types of slips of tongue and some analysis on it.

  3. Tongue as the Window to the Heart

    Institute of Scientific and Technical Information of China (English)

    Tsung O. Cheng

    2011-01-01

    To the Editor: I read with great interest your masterful article on study of the tongue in patients with coronary heart disease.Tongue is,indeed,the window to the heart.Many cardiovascular diseases including coronary heart disease can be accurately diagnosed by the Chinese traditional physicians by careful inspection of the tongue(Figure 1).

  4. Cortico-muscular synchronization by proprioceptive afferents from the tongue muscles during isometric tongue protrusion.

    Science.gov (United States)

    Maezawa, Hitoshi; Mima, Tatsuya; Yazawa, Shogo; Matsuhashi, Masao; Shiraishi, Hideaki; Funahashi, Makoto

    2016-03-01

    Tongue movements contribute to oral functions including swallowing, vocalizing, and breathing. Fine tongue movements are regulated through efferent and afferent connections between the cortex and tongue. It has been demonstrated that cortico-muscular coherence (CMC) is reflected at two frequency bands during isometric tongue protrusions: the beta (β) band at 15-35Hz and the low-frequency band at 2-10Hz. The CMC at the β band (β-CMC) reflects motor commands from the primary motor cortex (M1) to the tongue muscles through hypoglossal motoneuron pools. However, the generator mechanism of the CMC at the low-frequency band (low-CMC) remains unknown. Here, we evaluated the mechanism of low-CMC during isometric tongue protrusion using magnetoencephalography (MEG). Somatosensory evoked fields (SEFs) were also recorded following electrical tongue stimulation. Significant low-CMC and β-CMC were observed over both hemispheres for each side of the tongue. Time-domain analysis showed that the MEG signal followed the electromyography signal for low-CMC, which was contrary to the finding that the MEG signal preceded the electromyography signal for β-CMC. The mean conduction time from the tongue to the cortex was not significantly different between the low-CMC (mean, 80.9ms) and SEFs (mean, 71.1ms). The cortical sources of low-CMC were located significantly posterior (mean, 10.1mm) to the sources of β-CMC in M1, but were in the same area as tongue SEFs in the primary somatosensory cortex (S1). These results reveal that the low-CMC may be driven by proprioceptive afferents from the tongue muscles to S1, and that the oscillatory interaction was derived from each side of the tongue to both hemispheres. Oscillatory proprioceptive feedback from the tongue muscles may aid in the coordination of sophisticated tongue movements in humans.

  5. Sensor Arrays and Electronic Tongue Systems

    Directory of Open Access Journals (Sweden)

    Manel del Valle

    2012-01-01

    Full Text Available This paper describes recent work performed with electronic tongue systems utilizing electrochemical sensors. The electronic tongues concept is a new trend in sensors that uses arrays of sensors together with chemometric tools to unravel the complex information generated. Initial contributions and also the most used variant employ conventional ion selective electrodes, in which it is named potentiometric electronic tongue. The second important variant is the one that employs voltammetry for its operation. As chemometric processing tool, the use of artificial neural networks as the preferred data processing variant will be described. The use of the sensor arrays inserted in flow injection or sequential injection systems will exemplify attempts made to automate the operation of electronic tongues. Significant use of biosensors, mainly enzyme-based, to form what is already named bioelectronic tongue will be also presented. Application examples will be illustrated with selected study cases from the Sensors and Biosensors Group at the Autonomous University of Barcelona.

  6. Manipulators inspired by the tongue of the chameleon.

    Science.gov (United States)

    Debray, Alexis

    2011-06-01

    Chameleons have developed a specialized ballistic tongue which elongates more than six times its rest length at speeds higher than 3.5 m s(-1) and accelerations 350 m s(-2), with a highly flexible mobile part, and which applies no continuous force during forward motion. These characteristics are possible because this tongue consists of two highly specialized systems, an ejection system for the forward motion and an accordion-like system for the retraction. Four manipulators inspired by the tongue of the chameleon and based on this design have been developed, resulting in three characteristics similar to the tongue of the chameleon: extensibility of the manipulator, flexibility of the mobile part, and absence of continuous force during the forward motion. The first manipulator mimics the basic mechanism of the tongue of the chameleon and reproduced its basic performances. A second manipulator performs a catching function at a speed of 3.5 m s(-1) with an acceleration of 573 m s(-2) while elongating seven times its rest length. The design of this manipulator is such that the dc motor used for retraction applies a torque 25 times its rated torque. Moreover, during the retraction, the mobile part of the manipulator moves due to its own inertia, allowing the dc motor to rotate at full velocity. In another manipulator, the addition of an elastomer in the mobile part allows for control of the retraction velocity. A model for these two manipulators compares well with the experimental data. Finally, the addition of wings on the mobile part allows us to take the advantage of aerodynamic effects, which is unusual for manipulators.

  7. Biomechanics drive histological wall remodeling of neoaortic root: A mathematical model to study the expression levels of ki 67, metalloprotease, and apoptosis transition.

    Science.gov (United States)

    Nappi, Francesco; Fraldi, Massimiliano; Spadaccio, Cristiano; Carotenuto, Angelo Rosario; Montagnani, Stefania; Castaldo, Clotilde; Chachques, Juan Carlos; Acar, Christophe

    2016-11-01

    The pulmonary artery autograft (PA) is the ideal substitute for aortic valve disease in children and young adult. However, it is harnessed by the issue of long-term dilation and regurgitation, often requiring surgery. PA implanted in aortic position during the growth phase in children undergoes a process of mechanical remodeling. We previously developed a semiresorbable armored prosthesis able to mechanically sustain the neoaorta preventing dilation and to gradually integrate with the PA wall inducing a progressive arterial-like tissue positive remodeling. We also described the mechanisms of growth, remodeling and stress shielding of the reinforced PA through a mathematical model. We sought to demonstrate the biological counterpart and the potential molecular mechanisms underlying this histological and mechanical remodeling. A specific mathematical model was developed to describe mechanical behavior of the PA. Mallory trichrome red staining and immunohistochemistry for MMP-9 were performed to elucidate extracellular matrix remodeling phenomena. Apoptosis and cell proliferation were determined by TUNEL assay and immunohistochemistry for Ki67, respectively. An histological remodeling phenomenon sustained by increased level of MMP-9, augmented cell proliferation and reduced apoptosis in the reinforced PA was demonstrated. The mathematical model predicted the biomechanical behavior subtended by the histological changes of the PA in these settings. Changes in metalloproteinases (MMP-9), cell proliferation and apoptosis are the main actors in the remodeling process occurring after transposition of the PA into systemic regimens. Use of semiresorbable reinforcements might induce a positive remodeling of the PA in the context of Ross operation. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2785-2793, 2016.

  8. Paleoecology of the Niland Tongue

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, E.I.

    1987-01-01

    The swamp or paludal ecosystem is preserved in coals and carbonaceous shales. Remains of organisms of the swamp communities consist of bacteria and fungi; algae; invertebrates such as pelecypods, gastropods, ostracodes, and insects; vertebrates such as a hard-shelled turtle and crocodiles; and vascular plant remains. Aquatic communities are found in dark shale and are represented by the remains of bacteria and fungi; algae; invertebrates such as pelecypods, gastropods, and insects; and vertebrates such as crocodiles, fish, and a soft-shelled turtle. No vascular macrophytes (rooted aquatic vegetation) could be identified in the pollen and spore assemblage. Charophytes are abundant and show that colonies of the aquatic alga lived on the lake bottoms. The great variety of organisms suggests that the environment had a high input of nutrients. The phosphate-rich Phosphoria Formation, which could serve as a good source of nutrients, cropped out in the watershed of the Niland Tongue basin. The ostracode-crocodile association, calcareous charophytes, and good preservation of plant tissues and palynomorphs put limits on the alkaline geochemical environment in which the lacustrine rocks were deposited. The palynomorphs in the Niland Tongue rocks are dark yellow and light brown in color. These colors suggest that rocks containing them have been buried deeper in the past than they are today.

  9. Influence of visual observational conditions on tongue motor learning

    DEFF Research Database (Denmark)

    Kothari, Mohit; Liu, Xuimei; Baad-Hansen, Lene;

    2016-01-01

    feedback of their own TPT performance, Group 3: control group performed the TPT without any conditioning. There was no overall difference between groups but TPT performance increased over time. A significant group x time interaction indicated that the self-observation group performed significantly better...... than the model-observation group in the last 20 min of TPT. The subject-based reports of video helpfulness showed that the model-observation group rated the pre-recorded video as more helpful for TPT performance compared with the other groups but there was no significant difference between groups...... regarding the level of disturbance, pain or fatigue. Self-observation of tongue-training facilitated behavioral aspects of tongue motor learning compared with model-observation but not compared with control....

  10. Biomechanics of knife stab attacks.

    Science.gov (United States)

    Chadwick, E K; Nicol, A C; Lane, J V; Gray, T G

    1999-10-25

    Equipment, materials and methods for the measurement of the biomechanical parameters governing knife stab attacks have been developed and data have been presented that are relevant to the improvement of standards for the testing of stab-resistant materials. A six-camera Vicon motion analysis system was used to measure velocity, and derive energy and momentum during the approach phase of the attack and a specially developed force-measuring knife was used to measure three-dimensional forces and torque during the impact phase. The body segments associated with the knife were modelled as a series of rigid segments: trunk, upper arm, forearm and hand. The velocities of these segments, together with knowledge of the mass distribution from biomechanical tables, allowed the calculation of the individual segment energy and momentum values. The instrumented knife measured four components of load: axial force (along the length of the blade), cutting force (parallel to the breadth of the blade), lateral force (across the blade) and torque (twisting action) using foil strain gauges. Twenty volunteers were asked to stab a target with near maximal effort. Three styles of stab were used: a short thrust forward, a horizontal style sweep around the body and an overhand stab. These styles were chosen based on reported incidents, providing more realistic data than had previously existed. The 95th percentile values for axial force and energy were 1885 N and 69 J, respectively. The ability of current test methods to reproduce the mechanical parameters measured in human stab attacks has been assessed. It was found that current test methods could reproduce the range of energy and force values measured in the human stab attacks, although the simulation was not accurate in some respects. Non-axial force and torque values were also found to be significant in the human tests, but these are not reproduced in the standard mechanical tests.

  11. Biomechanics as a window into the neural control of movement.

    Science.gov (United States)

    Latash, Mark L

    2016-09-01

    Biomechanics and motor control are discussed as parts of a more general science, physics of living systems. Major problems of biomechanics deal with exact definition of variables and their experimental measurement. In motor control, major problems are associated with formulating currently unknown laws of nature specific for movements by biological objects. Mechanics-based hypotheses in motor control, such as those originating from notions of a generalized motor program and internal models, are non-physical. The famous problem of motor redundancy is wrongly formulated; it has to be replaced by the principle of abundance, which does not pose computational problems for the central nervous system. Biomechanical methods play a central role in motor control studies. This is illustrated with studies with the reconstruction of hypothetical control variables and those exploring motor synergies within the framework of the uncontrolled manifold hypothesis. Biomechanics and motor control have to merge into physics of living systems, and the earlier this process starts the better.

  12. Ergonomic Evaluation of Biomechanical Hand Function

    OpenAIRE

    Lee, Kyung-Sun; Jung, Myung-Chul

    2014-01-01

    The human hand is a complex structure that performs various functions for activities of daily living and occupations. This paper presents a literature review on the methodologies used to evaluate hand functions from a biomechanics standpoint, including anthropometry, kinematics, kinetics, and electromyography (EMG). Anthropometry describes the dimensions and measurements of the hand. Kinematics includes hand movements and the range of motion of finger joints. Kinetics includes hand models for...

  13. Potentiometric Electronic Tongue to Resolve Mixtures of Sulfide and Perchlorate Anions

    OpenAIRE

    2011-01-01

    This work describes the use of an array of potentiometric sensors and an artificial neural network response model to determine perchlorate and sulfide ions in polluted waters, by what is known as an electronic tongue. Sensors used have been all-solid-state PVC membrane selective electrodes, where their ionophores were different metal-phtalocyanine complexes with specific and anion generic responses. The study case illustrates the potential use of electronic tongues in the quantification of mi...

  14. Classification of Mixtures of Odorants from Livestock Buildings by a Sensor Array (an Electronic Tongue)

    OpenAIRE

    2007-01-01

    An electronic tongue comprising different numbers of electrodes was able to classify test mixtures of key odorants characteristic of bioscrubbers of livestock buildings (n-butyrate, iso-valerate, phenolate, p-cresolate, skatole and ammonium). The classification of model solutions indicates that the electronic tongue has a promising potential as an on- line sensor for characterization of odorants in livestock buildings. Back propagation artificial neural network was used for classification. Th...

  15. Interpreting locomotor biomechanics from the morphology of human footprints.

    Science.gov (United States)

    Hatala, Kevin G; Wunderlich, Roshna E; Dingwall, Heather L; Richmond, Brian G

    2016-01-01

    Fossil hominin footprints offer unique direct windows to the locomotor behaviors of our ancestors. These data could allow a clearer understanding of the evolution of human locomotion by circumventing issues associated with indirect interpretations of habitual locomotor patterns from fossil skeletal material. However, before we can use fossil hominin footprints to understand better the evolution of human locomotion, we must first develop an understanding of how locomotor biomechanics are preserved in, and can be inferred from, footprint morphologies. In this experimental study, 41 habitually barefoot modern humans created footprints under controlled conditions in which variables related to locomotor biomechanics could be quantified. Measurements of regional topography (depth) were taken from 3D models of those footprints, and principal components analysis was used to identify orthogonal axes that described the largest proportions of topographic variance within the human experimental sample. Linear mixed effects models were used to quantify the influences of biomechanical variables on the first five principal axes of footprint topographic variation, thus providing new information on the biomechanical variables most evidently expressed in the morphology of human footprints. The footprint's overall depth was considered as a confounding variable, since biomechanics may be linked to the extent to which a substrate deforms. Three of five axes showed statistically significant relationships with variables related to both locomotor biomechanics and substrate displacement; one axis was influenced only by biomechanics and another only by the overall depth of the footprint. Principal axes of footprint morphological variation were significantly related to gait type (walking or running), kinematics of the hip and ankle joints and the distribution of pressure beneath the foot. These results provide the first quantitative framework for developing hypotheses regarding the

  16. Biomechanical issues in endovascular device design.

    Science.gov (United States)

    Moore, James E

    2009-02-01

    The biomechanical nature of the arterial system and its major disease states provides a series of challenges to treatment strategies. Endovascular device design objectives have mostly centered on short-term challenges, such as deployability and immediate restoration of reliable flow channels. The resulting design features may be at odds with long-term clinical success. In-stent restenosis, endoleaks, and loss of device structural integrity (e.g., strut fractures) are all manifestations of a lack of compatibility between the host vessel biomechanical environment and the implant design. Initial attempts to adapt device designs for increased compatibility, including drug-eluting and bioabsorbable stents, barely begin to explore the ways in which implant design can be modulated in time to minimize risk of failure. Biomechanical modeling has the potential to provide a virtual vascular environment in which new designs can be tested for their implications on long-term tissue reaction. These models will be based on high quality, highly resolved imaging information, as well as mechanobiology experiments from the cellular to the whole tissue level. These models can then be extended to incorporate biodegradation mechanics, facilitating the next generations of devices whose designs (including drug delivery profiles) change with time to enhance healing. The possibility of initiating changes in device design or drug release according to information on vascular healing (through clinical intervention or automated methods) provides the opportunity for truly individualized dynamic device design optimization.

  17. A multiscale model for the study of cardiac biomechanics in single-ventricle surgeries: a clinical case.

    Science.gov (United States)

    Meoli, Alessio; Cutrì, Elena; Krishnamurthy, Adarsh; Dubini, Gabriele; Migliavacca, Francesco; Hsia, Tain-Yen; Pennati, Giancarlo; Taylor, Andrew; Giardini, Alessandro; Khambadkone, Sachin; Schievano, Silvia; de Leval, Marc; Hsia, T-Y; Bove, Edward; Dorfman, Adam; Baker, G Hamilton; Hlavacek, Anthony; Migliavacca, Francesco; Pennati, Giancarlo; Dubini, Gabriele; Marsden, Alison; Feinstein, Jeffrey; Vignon-Clementel, Irene; Figliola, Richard; McGregor, John

    2015-04-06

    Complex congenital heart disease characterized by the underdevelopment of one ventricular chamber (single ventricle (SV) circulation) is normally treated with a three-stage surgical repair. This study aims at developing a multiscale computational framework able to couple a patient-specific three-dimensional finite-element model of the SV to a patient-specific lumped parameter (LP) model of the whole circulation, in a closed-loop fashion. A sequential approach was carried out: (i) cardiocirculatory parameters were estimated by using a fully LP model; (ii) ventricular material parameters and unloaded geometry were identified by means of the stand-alone, three-dimensional model of the SV; and (iii) the three-dimensional model of SV was coupled to the LP model of the circulation, thus closing the loop and creating a multiscale model. Once the patient-specific multiscale model was set using pre-operative clinical data, the virtual surgery was performed, and the post-operative conditions were simulated. This approach allows the analysis of local information on ventricular function as well as global parameters of the cardiovascular system. This methodology is generally applicable to patients suffering from SV disease for surgical planning at different stages of treatment. As an example, a clinical case from stage 1 to stage 2 is considered here.

  18. CLINICAL PATHOLOGICAL FEATURE OF EARLY TONGUE AMYLOIDOSIS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective To investigate the clinical pathological feature and diagnostic criteria of tongue amyloidosis (AL).Methods During 1992 to 2005, 25 patients pathologically diagnosed as tongue AL in our hospital were reviewed retrospectively, and all of them had no enlarged tongue. Haematoxylin and eosin (HE) and immunohistochemical staining were used to detect the amyloid deposition on the tongue.Results Totally 84 % (21/25) patients had symptoms of xerostomia and taste-blindness, 44 % (11/25) patients complained of activity limitation of tongue. Macroscopic observation showed mucosa pallescence, punctuate hemorrhage, red grain particles, and ulcers on the tongue. HE staining indicated amyloid depositions in basement membrane,muscle cell, vessel wall, and nerve fiber. Immunohistochemical study demonstrated kappa light-chain deposition in 64%(16/25) cases, and lambda light-chain deposition in 36 % (9/25) cases. They presented in vessel wall, nerve fiber, and muscle cells.Conclusion The biopsy is an important means for the diagnosis of early tongue AL, and the wide variety of amyloid light chain is helpful to differential diagnosis.

  19. Surgical approaches for tongue base schwannoma.

    Science.gov (United States)

    Ying, Binbin; Zhu, Songsong; Qiao, Yang; Ye, Weimin; Maimaiti, Abdikerimjian; Hu, Jingzhou; Zhang, Yong

    2013-01-01

    Schwannomas (neurilemmomas) are benign nerve sheath tumor originating from Schwann cells. They are well circumscribed and rarely infiltrate and metastasize. Schwannomas of the head and neck commonly occur in the tongue followed by the palate, floor of mouth, buccal mucosa, and mandible. Tongue base schwannomas could extend to the pharyngeal cavity or the floor of the mouse, and it is difficult to differentiate between tumors of the lingual, hypoglossal, and glossopharyngeal nerves.Surgical treatment of tongue base schwannomas is difficult because of limited operative exposure. Although mandibulotomy with lip splitting could obtain good exposure, surgeons might strike a balance between exposure obtaining and morbidity following because there are intricate neurovascular anatomical relationships in this region, and mandibulotomy with lip splitting would cause significant morbidity. Surgical approach options are important for tongue base schwannoma removal. From March 2008 to March 2010, 8 patients were clinically and pathologically diagnosed with tongue base schwannomas in our department, and all underwent surgical treatment. In our experience, transoral approach was used for tongue base schwannomas extending to the floor of the mouse and suprahyroid pharyngotomy approach for those extending to the pharyngeal cavity. Follow-up was made until now. One patient who experienced transoral excision still experienced numbness in the region of the lateral tongue tip, and the other 7 patients had no postoperative long-term complications.

  20. Mother Tongue Tuition in Sweden - Curriculum Analysis and Classroom Experience

    Directory of Open Access Journals (Sweden)

    Anne REATH WARREN

    2013-10-01

    Full Text Available The model of Mother Tongue Tuition (MTT which has developed in Sweden since the 1970’s offers speakers of languages other than Swedish the opportunity to request tuition in their mother tongue, from kindergarten through to year 12. It is unique among the major immigrant-receiving countries of the world yet little is known about MTT and its syllabus outside of its Nordic context. This article examines the syllabus for MTT from two perspectives; firstly using the framework of Constructive Alignment, secondly from the perspective of what is hidden. The intended syllabus is revealed as well-aligned, but the hidden curriculum impedes successful enactment in many contexts. Examples from case studies in a larger on-going research project offer an alternate approach to syllabus implementation when the negative effects of the hidden curriculum are challenged. While highly context-specific, this model may represent a step in the right direction for implementation of the syllabus.

  1. The biomechanical behavior and host response to porcine-derived small intestine submucosa, pericardium and dermal matrix acellular grafts in a rat abdominal defect model.

    Science.gov (United States)

    Zhang, Jian; Wang, Guan Yu; Xiao, Yi Pin; Fan, Lie Ying; Wang, Qiang

    2011-10-01

    Several porcine-derived acellular biologic grafts are increasingly used in abdominal wall reconstruction due to the limitations of synthetic meshes in many clinical situations. However, relatively little is known so far about their comparative mechanical characteristics and performance after defect repair. We therefore investigated three most commonly used porcine-derived acellular biomaterials, small intestine submucosa (P-SIS), pericardium (P-PC) and acellular dermal matrix (P-ADM) immediately after prepared, and their effectiveness, biomechanical and histological characteristics in repairing full-thickness abdominal defect in a rat model. P-PC had the best native performance in the burst strength, tensile strength and ball burst among the three porcine-derived scaffolds. P-SIS showed a significantly higher water vapor transmission in comparison with P-PC or P-ADM. Abdominal wall defects in rats were all satisfied repaired with P-SIS, P-PC or P-ADM. No laxity or fistula was observed in the repaired abdominal wall in the P-SIS group up to 8 weeks after surgery. However, there was a tendency for high postoperative abdominal eventration in the P-ADM and P-PC groups as compared with the P-SIS group. With regard to overall aspects of the postoperative laxity, intra-abdominal adhesion formation, tensile stress, stretchability, and degree of tissue ingrowth in terms of collagen deposition and neovascularization, P-SIS exhibits clear advantages over P-PC as well as P-ADM after large abdominal wall defect reconstruction.

  2. Efficacy of radial styloid targeting screws in volar plate fixation of intra-articular distal radial fractures: a biomechanical study in a cadaver fracture model

    Directory of Open Access Journals (Sweden)

    Yamashita Toshihiko

    2010-12-01

    Full Text Available Abstract Background The locking screws target the radial styloid, theoretically provide greater stability against radial styloid fragment. However, it is unknown whether the radial styloid locking screws increased the stability of the volar plating system fixation along the entire distal radius or not. In this study, we evaluated the stability of the volar plating system fixation with or without the radial styloid screws using a biomechanical study in a cadaver fracture model. Methods Six matched pairs of fresh-frozen human cadaver wrists complete from the proximal forearm to the metacarpal bones were prepared to simulate standardized 3-part intra-articular and severe comminuted fractures. Specimens were fixed using the volar plating system with or without 2 radial styloid screws. Each specimen was loaded at a constant rate of 20 mm/min to failure. Load data was recorded and, ultimate strength and change in gap between distal and proximal fragments were measured. Data for ultimate strength and screw failure after failure loading were compared between the 2 groups. Results The average ultimate strength at failure of the volar plate fixation with radial styloid screws (913.5 ± 157.1 N was significantly higher than that without them (682.2 ± 118.6 N. After failure loading, the average change in gap between the ulnar and proximal fragment was greater than that between the radial and proximal fragment. The number of bent or broken screws in ulnar fragment was higher than that in radial fragment. The number of specimens with bent or broken screws in cases with radial styloid screws was fewer than that in the fixation without radial styloid screws group. Conclusion The ulnar fragment is more intensively stressed than the radial fragment under axial loading of distal radius at full wrist extension. The radial styloid screws were effective in stable volar plate fixation of distal radial fractures.

  3. Automatic Extraction of Tongue Coatings from Digital Images: A Traditional Chinese Medicine Diagnostic Tool

    Institute of Scientific and Technical Information of China (English)

    Linda Yunlu BAI; SHI Yundi; WU Jia; ZHANG Yonghong; WONG Weiliang; WU Yu; BAI Jing

    2009-01-01

    In traditional Chinese medicine, the coating on the tongue is considered to be a reflection of various pathologic factors. However, the conventional method to examine the tongue lacks an acceptable standard and does not provide the means for sharing information. This paper describes a segmentation method to extract tongue coatings. First, the tongue body was extracted from the original image using the watershed transform. Then, a threshold method was applied to the image to eliminate the light from the camera flash.Finally, a threshold method using the Otsu model in combination with a splitting-merging method was used in the red, green, and blue (RGB) space to extract the thin coating. The combination of the above two methods is applied in the hue, saturation, and value (HSV) space to extract the thick coating. The feasibility of this method is tested by experiments, and the accuracy of segmentation is 95.9%.

  4. The tongue, mandible, hyoid system

    Directory of Open Access Journals (Sweden)

    Giuseppe Messina

    2017-03-01

    Full Text Available The craniocervical-mandibular system works in harmony and allows different functional tasks as the postural control of the cervical region. This system is formed by the temporomandibular joint, the masticatory muscles and ligaments connecting the temporomandibular joint and the cervical region. It has been seen to affect human posture, and many disorders of the temporomandibular joints may affect this functional arrangement. Notwithstanding this system considered as a functional arrangement, may offer various clinical explanations, it does not hold anatomical connections with the posterior region of the cranium, thus it should not be refered to as a craniocervical arrangement. For this reason a new interpretation of such system as the tongue, mandible, hyoid system should be considered. Such functional reinterpretation between these three anatomical structures allows further comprehension of specific clinical conditions connected to deglutition aspects or the temporomandibular joint, for such needs to be taken into account during clinical diagnosis and treatment.

  5. Geometrical Dynamics of Complex Systems - A Unified Modelling Approach to Physics, Control, Biomechanics, Neurodynamics and Psycho-Socio-Economical Dynamics

    Science.gov (United States)

    Ivancevic, Vladimir G.; Ivancevic, Tijana T.

    The main objective is to show that high-dimensional nonlinear systems in "real life" can be modeled and analyzed using rigorous mathematics, which enables their complete predictability and controllability, as if they were linear systems.

  6. Electronic Tongue Containing Redox and Conductivity Sensors

    Science.gov (United States)

    Buehler, Martin

    2007-01-01

    The Electronic Tongue (E-tongue 2) is an assembly of sensors for measuring concentrations of metal ions and possibly other contaminants in water. Potential uses for electronic tongues include monitoring the chemical quality of water in a variety of natural, industrial, and laboratory settings, and detecting micro-organisms indirectly by measuring microbially influenced corrosion. The device includes a heater, a temperature sensor, an oxidation/reduction (redox) sensor pair, an electrical sensor, an array of eight galvanic cells, and eight ion-specific electrodes.

  7. Biomechanical response of the pediatric abdomen, part 1: development of an experimental model and quantification of structural response to dynamic belt loading.

    Science.gov (United States)

    Kent, Richard; Stacey, Stephen; Kindig, Matthew; Forman, Jason; Woods, William; Rouhana, Stephen W; Higuchi, Kazuo; Tanji, Hiromasa; Lawrence, Schuyler St; Arbogast, Kristy B

    2006-11-01

    The abdomen is the second most commonly injured region in children using adult seat belts, but engineers are limited in their efforts to design systems that mitigate these injuries since no current pediatric dummy has the capability to quantify injury risk from loading to the abdomen. This paper develops a porcine (sus scrofa domestica) model of the 6-year-old human's abdomen, and then defines the biomechanical response of this abdominal model. First, a detailed abdominal necropsy study was undertaken, which involved collecting a series of anthropometric measurements and organ masses on 25 swine, ranging in age from 14 to 429 days (4-101 kg mass). These were then compared to the corresponding human quantities to identify the best porcine representation of a 6-year-old human's abdomen. This was determined to be a pig of age 77 days, and whole-body mass of 21.4 kg. The sub-injury, quasistatic response to belt loading of this porcine model compared well with pediatric human volunteer tests performed with a lap belt on the lower abdomen. A test fixture was designed to produce transverse, dynamic belt loading on the porcine abdomen. A detailed review of field cases identified the following test variables: loading location (upper/lower), penetration magnitude (23%-68% of initial abdominal depth), muscle tensing (yes/no), and belt penetration rate (quasistatic, dynamic 2.9 m/s - 7.8 m/s). Dynamic tests were performed on 47 post-mortem subjects. Belt tension and dorsal reaction force were cross-plotted with abdominal penetration to generate structural response corridors. Subcutaneous stimulation of the anterior abdominal muscle wall stiffened the quasistatic response significantly, but was of negligible importance in the dynamic tests. The upper abdomen exhibited stiffer response quasistatically, and also was more sensitive to penetration rate, with stiffness increasing significantly over the range of dynamic rates tested here. In contrast, the lower abdomen was relatively

  8. Establishment and Evaluation of Tongue Diagnosis in Rat Stomach Real Heat Syndrome Model%胃实热证大鼠模型舌象诊断的建立及评价

    Institute of Scientific and Technical Information of China (English)

    官宗华; 宋捷民; 张世亮; 丁晓越

    2012-01-01

    Objective: To establish and evaluate the tongue diagnosis of rat stomach real heat syndrome model. Methods: The model was established by injection of indometacin (soluble in 5% NaHCO3 liquid, 10 mg/kg) and given a gavage of chili liquor mixture (10 mL/kg) with twice per day. After 1 week,the rat signs and tongue appearance were observed and the color difference including red , green and blue were analysed by photoshop image processing software. Some serum indices were detected by the ELISA method such as IL-6,IL-8,IL-10,ET-l, cAMP and PGE2. Results: A week later, the model rats appeared that their movements were reduced and weights were decreased. Meanwhile, their appetites were reduceding and dejecate was black and dry. Their tongues were more red and dark. The number of red, green and blue weres significantly lowered. Especially, the red was more obviously decreased. Contents including IL-6,IL-8,IL-10 and ET-1 were obviously increased. Levels such as cAMP and PGE2 were significantly lowered. Conclusion: The method of thermal factors combined with injecting indomethacin can establish the rat stomach real heat syndrome model.%目的 建立及评价大鼠胃实热证病理模型及舌象诊断方法.方法 采用腹腔注射吲哚美辛(溶于5%NaHCO3液中)10 mg/kg;灌饲辣椒、白酒混合液10 mL/kg,每日2次,造模1周.观察大鼠体征变化及舌外观,运用photoshop图片处理软件对大鼠舌象的色差红色、绿色、蓝色成分进行统计分析,并采用酶联免疫法检测大鼠血清中白细胞介素-6(IL-6)、白细胞介素-8(IL-8)、白细胞介素-10(IL-10)、内皮素-1(ET-1)、环磷酸腺苷(cAMP)、前列腺素E2(PGE2)的含量.结果 1周后可见胃实热组大鼠活动量减少,体质量减少,食量减少,便质黑于硬等症状;舌质红、暗,舌象红色、绿色、蓝色成分数值明显降低,特别是红色成分数值降低更加显著;血清中IL-6、IL-8、IL-10、ET-1含量明显增加,cAMP、PGE2

  9. Biomechanical conditions of walking

    CERN Document Server

    Fan, Y F; Luo, L P; Li, Z Y; Han, S Y; Lv, C S; Zhang, B

    2015-01-01

    The development of rehabilitation training program for lower limb injury does not usually include gait pattern design. This paper introduced a gait pattern design by using equations (conditions of walking). Following the requirements of reducing force to the injured side to avoid further injury, we developed a lower limb gait pattern to shorten the stride length so as to reduce walking speed, to delay the stance phase of the uninjured side and to reduce step length of the uninjured side. This gait pattern was then verified by the practice of a rehabilitation training of an Achilles tendon rupture patient, whose two-year rehabilitation training (with 24 tests) has proven that this pattern worked as intended. This indicates that rehabilitation training program for lower limb injury can rest on biomechanical conditions of walking based on experimental evidence.

  10. Prosthetic avian vocal organ controlled by a freely behaving bird based on a low dimensional model of the biomechanical periphery.

    Directory of Open Access Journals (Sweden)

    Ezequiel M Arneodo

    Full Text Available Because of the parallels found with human language production and acquisition, birdsong is an ideal animal model to study general mechanisms underlying complex, learned motor behavior. The rich and diverse vocalizations of songbirds emerge as a result of the interaction between a pattern generator in the brain and a highly nontrivial nonlinear periphery. Much of the complexity of this vocal behavior has been understood by studying the physics of the avian vocal organ, particularly the syrinx. A mathematical model describing the complex periphery as a nonlinear dynamical system leads to the conclusion that nontrivial behavior emerges even when the organ is commanded by simple motor instructions: smooth paths in a low dimensional parameter space. An analysis of the model provides insight into which parameters are responsible for generating a rich variety of diverse vocalizations, and what the physiological meaning of these parameters is. By recording the physiological motor instructions elicited by a spontaneously singing muted bird and computing the model on a Digital Signal Processor in real-time, we produce realistic synthetic vocalizations that replace the bird's own auditory feedback. In this way, we build a bio-prosthetic avian vocal organ driven by a freely behaving bird via its physiologically coded motor commands. Since it is based on a low-dimensional nonlinear mathematical model of the peripheral effector, the emulation of the motor behavior requires light computation, in such a way that our bio-prosthetic device can be implemented on a portable platform.

  11. Biomechanics of occlusion--implications for oral rehabilitation.

    Science.gov (United States)

    Peck, C C

    2016-03-01

    The dental occlusion is an important aspect of clinical dentistry; there are diverse functional demands ranging from highly precise tooth contacts to large crushing forces. Further, there are dogmatic, passionate and often diverging views on the relationship between the dental occlusion and various diseases and disorders including temporomandibular disorders, non-carious cervical lesions and tooth movement. This study provides an overview of the biomechanics of the masticatory system in the context of the dental occlusion's role in function. It explores the adaptation and precision of dental occlusion, its role in bite force, jaw movement, masticatory performance and its influence on the oro-facial musculoskeletal system. Biomechanics helps us better understand the structure and function of biological systems and consequently an understanding of the forces on, and displacements of, the dental occlusion. Biomechanics provides insight into the relationships between the dentition, jaws, temporomandibular joints, and muscles. Direct measurements of tooth contacts and forces are difficult, and biomechanical models have been developed to better understand the relationship between the occlusion and function. Importantly, biomechanical research will provide knowledge to help correct clinical misperceptions and inform better patient care. The masticatory system demonstrates a remarkable ability to adapt to a changing biomechanical environment and changes to the dental occlusion or other components of the musculoskeletal system tend to be well tolerated.

  12. Gait biomechanics in the era of data science.

    Science.gov (United States)

    Ferber, Reed; Osis, Sean T; Hicks, Jennifer L; Delp, Scott L

    2016-12-08

    Data science has transformed fields such as computer vision and economics. The ability of modern data science methods to extract insights from large, complex, heterogeneous, and noisy datasets is beginning to provide a powerful complement to the traditional approaches of experimental motion capture and biomechanical modeling. The purpose of this article is to provide a perspective on how data science methods can be incorporated into our field to advance our understanding of gait biomechanics and improve treatment planning procedures. We provide examples of how data science approaches have been applied to biomechanical data. We then discuss the challenges that remain for effectively using data science approaches in clinical gait analysis and gait biomechanics research, including the need for new tools, better infrastructure and incentives for sharing data, and education across the disciplines of biomechanics and data science. By addressing these challenges, we can revolutionize treatment planning and biomechanics research by capitalizing on the wealth of knowledge gained by gait researchers over the past decades and the vast, but often siloed, data that are collected in clinical and research laboratories around the world.

  13. Automatic Tongue Tracking in X-Ray Images

    Institute of Scientific and Technical Information of China (English)

    LUO Changwei; LI Rui; YU Lingyun; YU Jun; WANG Zengfu

    2015-01-01

    X-ray imaging is an eff ective technique to obtain the continuous motions of the vocal tract during speech, and Active appearance model (AAM) is a useful tool to analyze the X-ray images. However, for the task of tongue tracking in X-ray images, the accuracy of AAM fit-ting is insufficient. AAM aims to minimize the residual er-ror between the model appearance and the input image. It often fails to accurately converge to the true landmarks. To improve the tracking accuracy, we propose a fitting method by combining Constrained local model (CLM) into AAM. In our method, we first combine the objective functions of AAM and CLM into a single ob jective function. Then, we pro ject out the texture variation and derive a gradi-ent based method to optimize the objective function. Our method eff ectively incorporates not only the shape prior and global texture, but also local texture around each land-mark. Experiments demonstrate that the proposed method significantly reduces the fitting error. We also show that re-alistic 3D tongue animation can be created by using tongue tracking results of the X-ray images.

  14. SU-E-J-96: Multi-Axis Dose Accumulation of Noninvasive Image-Guided Breast Brachytherapy Through Biomechanical Modeling of Tissue Deformation Using the Finite Element Method

    Energy Technology Data Exchange (ETDEWEB)

    Rivard, MJ [Tufts University School of Medicine, Boston, MA (United States); Ghadyani, HR [SUNY Farmingdale State College, Farmingdale, NY (United States); Bastien, AD; Lutz, NN [Univeristy Massachusetts Lowell, Lowell, MA (United States); Hepel, JT [Rhode Island Hospital, Providence, RI (United States)

    2015-06-15

    Purpose: Noninvasive image-guided breast brachytherapy delivers conformal HDR Ir-192 brachytherapy treatments with the breast compressed, and treated in the cranial-caudal and medial-lateral directions. This technique subjects breast tissue to extreme deformations not observed for other disease sites. Given that, commercially-available software for deformable image registration cannot accurately co-register image sets obtained in these two states, a finite element analysis based on a biomechanical model was developed to deform dose distributions for each compression circumstance for dose summation. Methods: The model assumed the breast was under planar stress with values of 30 kPa for Young’s modulus and 0.3 for Poisson’s ratio. Dose distributions from round and skin-dose optimized applicators in cranial-caudal and medial-lateral compressions were deformed using 0.1 cm planar resolution. Dose distributions, skin doses, and dose-volume histograms were generated. Results were examined as a function of breast thickness, applicator size, target size, and offset distance from the center. Results: Over the range of examined thicknesses, target size increased several millimeters as compression thickness decreased. This trend increased with increasing offset distances. Applicator size minimally affected target coverage, until applicator size was less than the compressed target size. In all cases, with an applicator larger or equal to the compressed target size, > 90% of the target covered by > 90% of the prescription dose. In all cases, dose coverage became less uniform as offset distance increased and average dose increased. This effect was more pronounced for smaller target-applicator combinations. Conclusions: The model exhibited skin dose trends that matched MC-generated benchmarking results and clinical measurements within 2% over a similar range of breast thicknesses and target sizes. The model provided quantitative insight on dosimetric treatment variables over

  15. Amperometric Bioelectronic Tongue for glucose determination

    Directory of Open Access Journals (Sweden)

    Yazan Al-Issa

    2015-03-01

    Full Text Available An amperometric Bioelectronic Tongue is reported for glucose determination that contains eight sensor electrodes constructed using different metal electrodes (Pt, Au, oxidoreductase enzymes (glucose oxidase, ascorbate oxidase, uricase, and membrane coatings (Nafion, chitosan. The response to varying concentrations of glucose, ascorbic acid, uric acid, and acetaminophen was tested for two models, concentration determination by current density measurements at individual electrodes and concentration determination by a linear regression model for the entire electrode array. The reduced chi-squared for the full array model was found to be about one order of magnitude lower than that for the individual-electrode model. Discrimination of glucose from chemical interference by the other three species is accomplished through a combination of enzyme catalysis, metal electrocatalysis, and membrane surface charge. The benefit of incorporating enzyme electrodes into the sensor array is illustrated by the lower correlation coefficients between different enzyme electrodes relative to non-enzyme coated electrodes. This approach can be more generally applied to detection of other substrates of oxidoreductase enzymes.

  16. Time-Dependent Lagrangian Biomechanics

    CERN Document Server

    Ivancevic, Tijana T

    2009-01-01

    In this paper we present the time-dependent generalization of an 'ordinary' autonomous human musculo-skeletal biomechanics. We start with the configuration manifold of human body, given as a set of its all active degrees of freedom (DOF). This is a Riemannian manifold with a material metric tensor given by the total mass-inertia matrix of the human body segments. This is the base manifold for standard autonomous biomechanics. To make its time-dependent generalization, we need to extend it with a real time axis. On this extended configuration space we develop time-dependent biomechanical Lagrangian dynamics, using derived jet spaces of velocities and accelerations, as well as the underlying geometric evolution of the mass-inertia matrix. Keywords: Human time-dependent biomechanics, configuration manifold, jet spaces, geometric evolution

  17. Systems biomechanics of the cell

    CERN Document Server

    Maly, Ivan V

    2013-01-01

    Systems Biomechanics of the Cell attempts to outline systems biomechanics of the cell as an emergent and promising discipline. The new field owes conceptually to cell mechanics, organism-level systems biomechanics, and biology of biochemical systems. Its distinct methodology is to elucidate the structure and behavior of the cell by analyzing the unintuitive collective effects of elementary physical forces that interact within the heritable cellular framework. The problematics amenable to this approach includes the variety of cellular activities that involve the form and movement of the cell body and boundary (nucleus, centrosome, microtubules, cortex, and membrane). Among the elementary system effects in the biomechanics of the cell, instability of symmetry, emergent irreversibility, and multiperiodic dissipative motion can be noted. Research results from recent journal articles are placed in this unifying framework. It is suggested that the emergent discipline has the potential to expand the spectrum of ques...

  18. Potential screening and early diagnosis method for cancer: Tongue diagnosis.

    Science.gov (United States)

    Han, Shuwen; Yang, Xi; Qi, Quan; Pan, Yuefen; Chen, Yongchao; Shen, Junjun; Liao, Haihong; Ji, Zhaoning

    2016-06-01

    Tongue diagnosis, as a unique method of traditional Chinese medicine (TCM), was used to discriminate physiological functions and pathological conditions by observing the changes of the tongue and tongue coating. The aims of the present study were to explore a potential screening and early diagnosis method of cancer through evaluating the differences of the images of tongue and tongue coating and the microbiome on the tongue coating. The DS01-B tongue diagnostic information acquisition system was used to photograph and analyze the tongue and tongue coating. The next-generation sequencing technology was used to determine the V2-V4 hypervariable regions of 16S rDNA to investigate the microbiome on the tongue coating. Bioinformatics and statistical methods were used to analyze the microbial community structure and diversity. Comparing with the healthy people, the number of mirror-like tongue, thick tongue coating and the moisture of tongue were increased in cancers. The dominant color of the tongue in the healthy people was reddish while it was purple in the cancers. The relative abundance of Neisseria, Haemophilus, Fusobacterium and Porphyromonas in the healthy people were higher than that in the cancers. We also found 6 kinds of special microorganisms at species level in cancers. The study suggested that tongue diagnosis may provide potential screening and early diagnosis method for cancer.

  19. A biomechanical model of swallowing for understanding the influence of saliva and food bolus viscosity on flavour release

    CERN Document Server

    De Loubens, Clément; Doyennette, Marion; Tréléa, Ioan Cristian; Souchon, Isabelle

    2013-01-01

    After swallowing a liquid or a semi-liquid food product, a thin film responsible for the dynamic profile of aroma release coats the pharyngeal mucosa. The objective of the present article was to understand and quantify physical mechanisms explaining pharyngeal mucosa coating. An elastohydrodynamic model of swallowing was developed for Newtonian liquids that focused on the most occluded region of the pharyngeal peristaltic wave. The model took lubrication by a saliva film and mucosa deformability into account. Food bolus flow rate and generated load were predicted as functions of three dimensionless variables: the dimensionless saliva flow rate, the viscosity ratio between saliva and the food bolus, and the elasticity number. Considering physiological conditions, the results were applied to predict aroma release kinetics. Two sets of conditions were distinguished. The first one was obtained when the saliva film is thin, in which case food bolus viscosity has a strong impact on mucosa coating and on flavour rel...

  20. Instruction in the Mother Tongues in Yugoslavia.

    Science.gov (United States)

    Mikes, Melanie

    1984-01-01

    Educational practices and problems in Yugoslavia with regard to bilingual education are described. The effect of mother-tongue education on the students' academic achievement and literacy attainment is also examined. (RM)

  1. Transfer of mother tongue in SLA

    Institute of Scientific and Technical Information of China (English)

    米海燕

    2012-01-01

    In SLA transfer of mother tongue can not be overlooked. And we group it into positive transfer and negative transfer, which are reflected on different levels including pronunciation, vocabulary, syntax and culture.

  2. Investigation of the Chinese rolling tongue consonants

    Institute of Scientific and Technical Information of China (English)

    ZHOU Ligang; Keni'ti Kido

    2000-01-01

    Some special monosyllabic Chinese words which contain rolling tongue consonants are discussed. Based on the spectrum analysis, the special characteristic is found at a frequency higher than 3 kHz. The distinction is not only in the consonant part but also in the vowel part.The people in the north region of China distinguish the rolling tongue consonants from the straight tongue consonants both in utterance and in hearing, but those in the south region of China do not. The results of the hearing investigation using synthesized speech show that the consonant part corresponding to the normal one has more effect than the vowel part on the recognition of the words containing the rolling tongue consonant.

  3. Giant Plexiform Schwannoma of the Tongue

    OpenAIRE

    2011-01-01

    We present the case of a 38-year-old woman that presented with a very slowly enlarging mass of the tongue. MRI revealed a large mass originating in the tongue base and extending to the supraglottic space. Biopsy of this tumor confirmed the diagnosis of schwannoma. An endaural approach allowed complete resection of the tumor. Definitive histopathological examination showed a plexiform schwannoma. Schwannoma or neurilemoma represents a benign tumor potentially affecting any nerve. The head and ...

  4. Biomechanics of pediatric manual wheelchair mobility

    Directory of Open Access Journals (Sweden)

    Brooke A. Slavens

    2015-09-01

    Full Text Available Currently, there is limited research of the biomechanics of pediatric manual wheelchair mobility. Specifically, the biomechanics of functional tasks and their relationship to joint pain and health is not well understood. To contribute to this knowledge gap, a quantitative rehabilitation approach was applied for characterizing upper extremity biomechanics of manual wheelchair mobility in children and adolescents during propulsion, starting and stopping tasks. A Vicon motion analysis system captured movement, while a SmartWheel simultaneously collected three-dimensional forces and moments occurring at the hand-rim. A custom pediatric inverse dynamics model was used to evaluate three-dimensional upper extremity joint motions, forces and moments of 14 children with spinal cord injury (SCI during the functional tasks. Additionally, pain and health-related quality of life outcomes were assessed. This research found that joint demands are significantly different amongst functional tasks, with greatest demands placed on the shoulder during the starting task. Propulsion was significantly different from starting and stopping at all joints. We identified multiple stroke patterns used by the children, some of which are not standard in adults. One subject reported average daily pain, which was minimal. Lower than normal physical health and higher than normal mental health was found in this population. It can be concluded that functional tasks should be considered in addition to propulsion for rehabilitation and SCI treatment planning. This research provides wheelchair users and clinicians with a comprehensive, biomechanical, mobility assessment approach for wheelchair prescription, training, and long-term care of children with SCI.

  5. A method to characterize average cervical spine ligament response based on raw data sets for implementation into injury biomechanics models.

    Science.gov (United States)

    Mattucci, Stephen F E; Cronin, Duane S

    2015-01-01

    Experimental testing on cervical spine ligaments provides important data for advanced numerical modeling and injury prediction; however, accurate characterization of individual ligament response and determination of average mechanical properties for specific ligaments has not been adequately addressed in the literature. Existing methods are limited by a number of arbitrary choices made during the curve fits that often misrepresent the characteristic shape response of the ligaments, which is important for incorporation into numerical models to produce a biofidelic response. A method was developed to represent the mechanical properties of individual ligaments using a piece-wise curve fit with first derivative continuity between adjacent regions. The method was applied to published data for cervical spine ligaments and preserved the shape response (toe, linear, and traumatic regions) up to failure, for strain rates of 0.5s(-1), 20s(-1), and 150-250s(-1), to determine the average force-displacement curves. Individual ligament coefficients of determination were 0.989 to 1.000 demonstrating excellent fit. This study produced a novel method in which a set of experimental ligament material property data exhibiting scatter was fit using a characteristic curve approach with a toe, linear, and traumatic region, as often observed in ligaments and tendons, and could be applied to other biological material data with a similar characteristic shape. The resultant average cervical spine ligament curves provide an accurate representation of the raw test data and the expected material property effects corresponding to varying deformation rates.

  6. A computational fluid–structure interaction model to predict the biomechanical properties of the artificial functionally graded aorta

    Science.gov (United States)

    Khosravi, Arezoo; Bani, Milad Salimi; Bahreinizade, Hossein; Karimi, Alireza

    2016-01-01

    In the present study, three layers of the ascending aorta in respect to the time and space at various blood pressures have been simulated. Two well-known commercial finite element (FE) software have used to be able to provide a range of reliable numerical results while independent on the software type. The radial displacement compared with the time as well as the peripheral stress and von Mises stress of the aorta have calculated. The aorta model was validated using the differential quadrature method (DQM) solution and, then, in order to design functionally graded materials (FGMs) with different heterogeneous indexes for the artificial vessel, two different materials have been employed. Fluid–structure interaction (FSI) simulation has been carried out on the FGM and a natural vessel of the human body. The heterogeneous index defines the variation of the length in a function. The blood pressure was considered to be a function of both the time and location. Finally, the response characteristics of functionally graded biomaterials (FGBMs) models with different values of heterogeneous material parameters were determined and compared with the behaviour of a natural vessel. The results showed a very good agreement between the numerical findings of the FGM materials and that of the natural vessel. The findings of the present study may have implications not only to understand the performance of different FGMs in bearing the stress and deformation in comparison with the natural human vessels, but also to provide information for the biomaterials expert to be able to select a suitable material as an implant for the aorta. PMID:27836981

  7. A computational fluid-structure interaction model to predict the biomechanical properties of the artificial functionally graded aorta.

    Science.gov (United States)

    Khosravi, Arezoo; Bani, Milad Salimi; Bahreinizade, Hossein; Karimi, Alireza

    2016-12-01

    In the present study, three layers of the ascending aorta in respect to the time and space at various blood pressures have been simulated. Two well-known commercial finite element (FE) software have used to be able to provide a range of reliable numerical results while independent on the software type. The radial displacement compared with the time as well as the peripheral stress and von Mises stress of the aorta have calculated. The aorta model was validated using the differential quadrature method (DQM) solution and, then, in order to design functionally graded materials (FGMs) with different heterogeneous indexes for the artificial vessel, two different materials have been employed. Fluid-structure interaction (FSI) simulation has been carried out on the FGM and a natural vessel of the human body. The heterogeneous index defines the variation of the length in a function. The blood pressure was considered to be a function of both the time and location. Finally, the response characteristics of functionally graded biomaterials (FGBMs) models with different values of heterogeneous material parameters were determined and compared with the behaviour of a natural vessel. The results showed a very good agreement between the numerical findings of the FGM materials and that of the natural vessel. The findings of the present study may have implications not only to understand the performance of different FGMs in bearing the stress and deformation in comparison with the natural human vessels, but also to provide information for the biomaterials expert to be able to select a suitable material as an implant for the aorta.

  8. CURRENT CONCEPTS IN BIOMECHANICAL INTERVENTIONS FOR PATELLOFEMORAL PAIN

    Science.gov (United States)

    Meira, Erik P.

    2016-01-01

    Patellofemoral pain (PFP) has historically been a complex and enigmatic issue. Many of the factors thought to relate to PFP remain after patients' symptoms have resolved making their clinical importance difficult to determine. The tissue homeostasis model proposed by Dye in 2005 can assist with understanding and implementing biomechanical interventions for PFP. Under this model, the goal of interventions for PFP should be to re-establish patellofemoral joint (PFJ) homeostasis through a temporary alteration of load to the offended tissue, followed by incrementally restoring the envelope of function to the baseline level or higher. High levels of PFJ loads, particularly in the presence of an altered PFJ environment, are thought to be a factor in the development of PFP. Clinical interventions often aim to alter the biomechanical patterns that are thought to result in elevated PFJ loads while concurrently increasing the load tolerance capabilities of the tissue through therapeutic exercise. Biomechanics may play a role in PFJ load modification not only when addressing proximal and distal components, but also when considering the involvement of more local factors such as the quadriceps musculature. Biomechanical considerations should consider the entire kinetic chain including the hip and the foot/ankle complex, however the beneficial effects of these interventions may not be the result of long-term biomechanical changes. Biomechanical alterations may be achieved through movement retraining, but the interventions likely need to be task-specific to alter movement patterns. The purpose of this commentary is to describe biomechanical interventions for the athlete with PFP to encourage a safe and complete return to sport. Level of Evidence 5 PMID:27904791

  9. [Research progress on the risk factors of geographic tongue].

    Science.gov (United States)

    Huamei, Yang; Yu, Zhou; Xin, Zeng; Ga, Liao; Qianming, Chen

    2015-02-01

    Geographic tongue, also called benign migratory glossitis, is a common and superficial benign inflammatory disorder that affects the tongue epithelium. The majority of geographic tongue lesions typically manifest as irregular central erythematous patches. These lesions, which are caused by the loss of filiform papillae, are defined by an elevated whitish band-like border that can change location, size, and pattern over a period of time. Histological observations of the oral mucosa affected by geographic tongue revealed nonspecific inflammation. Some reports described cases of migratory stomatitis, wherein lesions simultaneously manifested on the extra lingual oral mucosa. This condition is also called ectopic geographic tongue, which is clinically and histologically similar to the type normally confined to the tongue. In most cases, patients are asymptomatic and do not require treatment. The condition may spontaneously exhibit periods of remission and exacerbation with good prognosis. The specific etiology of geographic tongue remains unknown. Geographic tongue is age-related and is prevalent among young individuals. Various etiological factors that have been suggested in literature include immunological factors, genetic factors, atopic or allergic tendency, emotional stress, tobacco consumption, hormonal disturbances, and zinc deficiency. Geographic tongue may coexist with other disorders, such as fissured tongue, psoriasis, diabetes mellitus, gastroin- testinal diseases, burning mouth syndrome, and Down syndrome. Experts currently disagree on whether geographic tongue is an oral manifestation of psoriasis. Moreover, some scholars suggest that geographic tongue is a prestage of fissured tongue. The objective of this review is to summarize current research on risk factors of geographic tongue.

  10. Sensory intensity assessment of olive oils using an electronic tongue.

    Science.gov (United States)

    Veloso, Ana C A; Dias, Luís G; Rodrigues, Nuno; Pereira, José A; Peres, António M

    2016-01-01

    Olive oils may be commercialized as intense, medium or light, according to the intensity perception of fruitiness, bitterness and pungency attributes, assessed by a sensory panel. In this work, the capability of an electronic tongue to correctly classify olive oils according to the sensory intensity perception levels was evaluated. Cross-sensitivity and non-specific lipid polymeric membranes were used as sensors. The sensor device was firstly tested using quinine monohydrochloride standard solutions. Mean sensitivities of 14±2 to 25±6 mV/decade, depending on the type of plasticizer used in the lipid membranes, were obtained showing the device capability for evaluating bitterness. Then, linear discriminant models based on sub-sets of sensors, selected by a meta-heuristic simulated annealing algorithm, were established enabling to correctly classify 91% of olive oils according to their intensity sensory grade (leave-one-out cross-validation procedure). This capability was further evaluated using a repeated K-fold cross-validation procedure, showing that the electronic tongue allowed an average correct classification of 80% of the olive oils used for internal-validation. So, the electronic tongue can be seen as a taste sensor, allowing differentiating olive oils with different sensory intensities, and could be used as a preliminary, complementary and practical tool for panelists during olive oil sensory analysis.

  11. Intrabody application of eptotermin alpha enhances bone formation in osteoporotic fractures of the lumbar spine; however, fails to increase biomechanical stability - results of an experimental sheep model.

    Science.gov (United States)

    Eschler, Anica; Roepenack, Paula; Herlyn, Philipp Karl Ewald; Roesner, Jan; Martin, Heiner; Vollmar, Brigitte; Mittlmeier, Thomas; Gradl, Georg

    2015-01-01

    This study analyses the effect of eptotermin α application into fractured vertebrae. It is hypothesized that eptotermin α is capable to enhance bony healing of the osteoporotic spine. In 10 Merino sheep osteoporosis induction was performed by ovariectomy, corticosteroid therapy and calcium/phosphorus/vitamin D-deficient diet; followed by standardized creation of lumbar vertebral compression fractures (VCFs) type A3.1 and consecutive fracture reduction/fixation using expandable mesh cages. Randomly, intravertebral eptotermin α (G1) or no augmentation was added (G2). Macroscopic, micro-CT, and biomechanical evaluation assessed bony consolidation two months postoperatively: Micro-CT data revealed bony consolidation for all cases with significant increased callus development for G2 (60%) and BV/TV (bone volume/total volume 73.45%, osteoporotic vertebrae 35.76%). Neither group showed improved biomechanical stability. Eptotermin α enhanced mineralisation in VCFs in an experimental setup with use of cementless augmentation via an expandable cage. However, higher bone mineral density did not lead to superior biomechanical properties.

  12. Repeated tongue lift movement induces neuroplasticity in corticomotor control of tongue and jaw muscles in humans.

    Science.gov (United States)

    Komoda, Yoshihiro; Iida, Takashi; Kothari, Mohit; Komiyama, Osamu; Baad-Hansen, Lene; Kawara, Misao; Sessle, Barry; Svensson, Peter

    2015-11-19

    This study investigated the effect of repeated tongue lift training (TLT) on the excitability of the corticomotor representation of the human tongue and jaw musculature. Sixteen participants performed three series of TLT for 41 min on each of 5 consecutive days. Each TLT series consisted of two pressure levels (5 kPa and 10 kPa). All participants underwent transcranial magnetic stimulation (TMS) and electromyographic (EMG) recordings of motor evoked potentials (MEPs) in four sessions: (1) before TLT on Day 1 (baseline), (2) after TLT on Day 1, (3) before TLT on Day 5, and (4) after TLT on Day 5. EMG recordings from the left and right tongue dorsum and masseter muscles were made at three pressure levels (5 kPa, 10 kPa, 100% tongue lift), and tongue, masseter, and first dorsal interosseous (FDI) MEPs were measured. There were no significant day-to-day differences in the tongue pressure during maximum voluntary contractions. The amplitudes and thresholds of tongue and masseter MEPs after TLT on Day 5 were respectively higher and lower than before TLT on Day 1 (Ptongue and masseter MEP areas; no significant changes occurred in MEP onset latencies. FDI MEP parameters (amplitude, threshold, area, latency) were not significantly different between the four sessions. Our findings suggest that repeated TLT can trigger neuroplasticity reflected in increased excitability of the corticomotor representation of not only the tongue muscles but also the masseter muscles.

  13. Does bilingualism twist your tongue?

    Science.gov (United States)

    Gollan, Tamar H; Goldrick, Matthew

    2012-12-01

    The current study investigated whether bilingualism affects the processing of sub-lexical representations specifying the sound structure of words. Spanish-English bilinguals, Mandarin-English bilinguals, and English-only monolinguals repeated English tongue twisters. Twister materials had word or nonword targets (thus varying in whether lexical information did or did not support sound processing), and similar or dissimilar sounds (thus varying in difficulty with respect to competition at a sub-lexical level). Even though bilinguals had learned English at an early age, and spoke English without an accent, Spanish-English bilinguals produced significantly more twister errors than monolinguals, particularly in the absence of lexical support. Mandarin-English bilinguals were also disadvantaged, but more consistently across all twister types. These results reveal that bilingual disadvantages extend beyond the lexical level to affect the processing of sub-lexical representations. More generally, these findings suggest that experience with sound structures (and not simply their intrinsic complexity) shapes sub-lexical processing for all speakers.

  14. Judo Biomechanical Optimization

    CERN Document Server

    Sacripanti, Attilio

    2016-01-01

    In this paper, for the first time, there is comprehensively tackling the problem of biomechanical optimization of a sport of situation such as judo. Starting from the optimization of more simple sports, optimization of this kind of complex sports is grounded on a general physics tool such as the analysis of variation. The objective function is divided for static and dynamic situation of Athletes couple, and it is proposed also a sort of dynamic programming problem Strategic Optimization. A dynamic programming problem is an optimization problem in which decisions have to be taken sequentially over several time periods linked in some fashion. A strategy for a dynamic programming problem is just a contingency plan, a plan that specifies what is to be done at each stage as a function of all that has transpired up to that point. It is possible to demonstrate, under some conditions, that a Markovian optimal strategy is an optimal strategy for the dynamic programming problem under examination. At last we try to appr...

  15. Influence of the ability to roll the tongue and tongue-training parameters on oral motor performance and learning

    DEFF Research Database (Denmark)

    Kothari, Mohit; Svensson, Peter; Basic, Aida;

    2011-01-01

    OBJECTIVE: Training of tongue function is an important part of rehabilitation of patients with brain damage. A standardized tongue-training task has been shown to induce cortical plasticity. This study tested the possible influence of the natural ability to roll the tongue and modulations of tongue......-training parameters on tongue-training performance. DESIGN: A total of 44 healthy adult subjects participated. 29 subjects (15 with and 14 without ability to roll their tongue) performed 1h standard tongue-training task. Another 15 subjects participated in 2 sessions: Standard and Modulation in randomized order....... Standard session: 1h tongue-training with fixed training parameters; Modulation session: 1h tongue-training with modulation of training parameters every 20min (3 different settings - A, B, C, with different timing of task). Perceived task difficulty was evaluated on a 0-10 numerical rating scale (NRS...

  16. Visualized attribute analysis approach for characterization and quantification of rice taste flavor using electronic tongue

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Lin; Hu, Xianqiao [Rice Product Quality Supervision and Inspection Center, Ministry of Agriculture, China National Rice Research Institute, Hangzhou 310006 (China); Tian, Shiyi; Deng, Shaoping [College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310035 (China); Zhu, Zhiwei, E-mail: 615834652@qq.com [Rice Product Quality Supervision and Inspection Center, Ministry of Agriculture, China National Rice Research Institute, Hangzhou 310006 (China)

    2016-05-05

    This paper deals with a novel visualized attributive analysis approach for characterization and quantification of rice taste flavor attributes (softness, stickiness, sweetness and aroma) employing a multifrequency large-amplitude pulse voltammetric electronic tongue. Data preprocessing methods including Principal Component Analysis (PCA) and Fast Fourier Transform (FFT) were provided. An attribute characterization graph was represented for visualization of the interactive response in which each attribute responded by specific electrodes and frequencies. The model was trained using signal data from electronic tongue and attribute scores from artificial evaluation. The correlation coefficients for all attributes were over 0.9, resulting in good predictive ability of attributive analysis model preprocessed by FFT. This approach extracted more effective information about linear relationship between electronic tongue and taste flavor attribute. Results indicated that this approach can accurately quantify taste flavor attributes, and can be an efficient tool for data processing in a voltammetric electronic tongue system. - Graphical abstract: Schematic process for visualized attributive analysis approach using multifrequency large-amplitude pulse voltammetric electronic tongue for determination of rice taste flavor attribute. (a) sample; (b) sensors in electronic tongue; (c) excitation voltage program and response current signal from MLAPS; (d) similarity data matrix by data preprocessing and similarity extraction; (e) feature data matrix of attribute; (f) attribute characterization graph; (g) attribute scores predicted by the model. - Highlights: • Multifrequency large-amplitude pulse voltammetric electronic tongue was used. • A visualized attributive analysis approach was created as an efficient tool for data processing. • Rice taste flavor attribute was determined and predicted. • The attribute characterization graph was represented for visualization of the

  17. The biomechanics of soccer: a review.

    Science.gov (United States)

    Lees, A; Nolan, L

    1998-04-01

    surface types over a period of several games. Therefore, changing from one surface to another is a major aetiological factor in surface-related injuries. Heading the ball could lead to long-term brain damage. Simulation studies suggest the importance of ball mass, ball speed and player mass in affecting the severity of impact. Careful instruction and skill development, together with the correct equipment, is necessary for young players. Most applications of biomechanical techniques to soccer have been descriptive experimental studies. Biomechanical modelling techniques have helped in the understanding of the underlying mechanisms of performance, although their use has been limited. It is concluded that there are still many features of the game of soccer that are amenable to biomechanical treatment, and many opportunities for biomechanists to make a contribution to the science of soccer.

  18. A new methodology to measure the running biomechanics of amputees.

    Science.gov (United States)

    Wilson, James Richard; Asfour, Shihab; Abdelrahman, Khaled Zakaria; Gailey, Robert

    2009-09-01

    We present a new methodology to measure the running biomechanics of amputees. This methodology combines the use of a spring-mass model and symmetry index, two standard techniques in biomechanics literature, but not yet used in concert to evaluate amputee biomechanics. The methodology was examined in the context of a pilot study to examine two transtibial amputee sprinters and showed biomechanically quantifiable changes for small adjustments in prosthetic prescription. Vertical ground reaction forces were measured in several trials for two transtibial amputees running at constant speed. A spring-mass model was used in conjunction with a symmetry index to observe the effect of varying prosthetic height and stiffness on running biomechanics. All spring-mass variables were significantly affected by changes in prosthetic prescription among the two subjects tested (p < 0.05). When prosthetic height was changed, both subjects showed significant differences, in Deltay(max), Deltal and contact time (t(c)) on the prosthetic limb and in k(vert) and k(leg) on the sound limb. The symmetry indices calculated for spring-mass variables were all significantly affected due to changes in prosthetic prescription for the male subject and all but the peak force (F(peak)) for the female subject. This methodology is a straight-forward tool for evaluating the effect of changes to prosthetic prescription.

  19. The biomechanics of seed germination.

    Science.gov (United States)

    Steinbrecher, Tina; Leubner-Metzger, Gerhard

    2016-12-07

    From a biomechanical perspective, the completion of seed (and fruit) germination depends on the balance of two opposing forces: the growth potential of the embryonic axis (radicle-hypocotyl growth zone) and the restraint of the seed-covering layers (endosperm, testa, and pericarp). The diverse seed tissues are composite materials which differ in their dynamic properties based on their distinct cell wall composition and water uptake capacities. The biomechanics of embryo cell growth during seed germination depend on irreversible cell wall loosening followed by water uptake due to the decreasing turgor, and this leads to embryo elongation and eventually radicle emergence. Endosperm weakening as a prerequisite for radicle emergence is a widespread phenomenon among angiosperms. Research into the biochemistry and biomechanics of endosperm weakening has demonstrated that the reduction in puncture force of a seed's micropylar endosperm is environmentally and hormonally regulated and involves tissue-specific expression of cell wall remodelling proteins such as expansins, diverse hydrolases, and the production of directly acting apoplastic reactive oxygen. The endosperm-weakening biomechanics and its underlying cell wall biochemistry differ between the micropylar (ME) and chalazal (CE) endosperm domains. In the ME, they involve cell wall loosening, cell separation, and programmed cell death to provide decreased and localized ME tissue resistance, autolysis, and finally the formation of an ME hole required for radicle emergence. Future work will further unravel the molecular mechanisms, environmental regulation, and evolution of the diverse biomechanical cell wall changes underpinning the control of germination by endosperm weakening.

  20. Kinesiology/Biomechanics: Perspectives and Trends.

    Science.gov (United States)

    Atwater, Anne E.

    1980-01-01

    Past and recent developments and future directions in kinesiology and biomechanics are reviewed. Similarities and differences between these two areas are clarified. The areas of kinesiology and biomechanics have distinct unique qualities and should be treated as separate disciplines. (CJ)

  1. Bitterness prediction of H1-antihistamines and prediction of masking effects of artificial sweeteners using an electronic tongue.

    Science.gov (United States)

    Ito, Masanori; Ikehama, Kiyoharu; Yoshida, Koichi; Haraguchi, Tamami; Yoshida, Miyako; Wada, Koichi; Uchida, Takahiro

    2013-01-30

    The study objective was to quantitatively predict a drug's bitterness and estimate bitterness masking efficiency using an electronic tongue (e-Tongue). To verify the predicted bitterness by e-Tongue, actual bitterness scores were determined by human sensory testing. In the first study, bitterness intensities of eight H(1)-antihistamines were assessed by comparing the Euclidean distances between the drug and water. The distances seemed not to represent the drug's bitterness, but to be greatly affected by acidic taste. Two sensors were ultimately selected as best suited to bitterness evaluation, and the data obtained from the two sensors depicted the actual taste map of the eight drugs. A bitterness prediction model was established with actual bitterness scores from human sensory testing. Concerning basic bitter substances, such as H(1)-antihistamines, the predictability of bitterness intensity using e-Tongue was considered to be sufficiently promising. In another study, the bitterness masking efficiency when adding an artificial sweetener was estimated using e-Tongue. Epinastine hydrochloride aqueous solutions containing different levels of acesulfame potassium and aspartame were well discriminated by e-Tongue. The bitterness masking efficiency of epinastine hydrochloride with acesulfame potassium was successfully predicted using e-Tongue by several prediction models employed in the study.

  2. Biomechanics of Wheat/Barley Straw and Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Christopher T. Wright; Peter A. Pryfogle; Nathan A. Stevens; Eric D. Steffler; J. Richard Hess; Thomas H. Ulrich

    2005-03-01

    The lack of understanding of the mechanical characteristics of cellulosic feedstocks is a limiting factor in economically collecting and processing crop residues, primarily wheat and barley stems and corn stover. Several testing methods, including compression, tension, and bend have been investigated to increase our understanding of the biomechanical behavior of cellulosic feedstocks. Biomechanical data from these tests can provide required input to numerical models and help advance harvesting, handling, and processing techniques. In addition, integrating the models with the complete data set from this study can identify potential tools for manipulating the biomechanical properties of plant varieties in such a manner as to optimize their physical characteristics to produce higher value biomass and more energy efficient harvesting practices.

  3. Research on the biomechanical properties of spine based on the 3D finite demem model%基于三维有限元模型的脊柱生物力学特性研究进展

    Institute of Scientific and Technical Information of China (English)

    李芳燕; 黄永锋

    2008-01-01

    脊柱相关疾病研究是一门新兴的边缘学科,其研究重点即为脊柱的生物力学特性.综合分析了基于三维有限元模型的腰椎和颈椎生物力学特性研究方法;总结出有限元建模的三种方法,即几何建模法、三维坐标仪建模法以及图像建模法;提炼出图像建模法的关键步骤,即几何模型的建立、椎骨和软组织的材料特性定义、边界条件定义以及模型验证分析;最后提出有限元建模的两个主要改进方面及其研究趋势.%The research of spine related disease is an emerging interdisciplinary subject and the key point is the spinal biomechanical properties.In this paper,the method of studying biomechanical properties of lumhar and cervical vertebra based on 3D finite element model is analyzed.Three kinds of method in building finite element model are specified:geometric modeling method,3D coordinatngraphic modeling method and image modeling method.The three key steps of image modeling method for building of basic geometric model are extracted as defining material behavior of vertebra and soft tissue,defining boundary condition,and confirming of the model.Then two principal improving aspects of building finite element model and the foreground of the research are discussed.

  4. Biomechanics and the wheelchair.

    Science.gov (United States)

    McLaurin, C A; Brubaker, C E

    1991-04-01

    Wheelchair biomechanics involves the study of how a wheelchair user imparts power to the wheels to achieve mobility. Because a wheelchair can coast, power input need not be continuous, but each power strike can be followed by a period of recovery, with the stroking frequency depending on user preferences and the coasting characteristics of the wheelchair. The latter is described in terms of rolling resistance, wind resistance and the slope of the surface. From these three factors the power required to propel the wheelchair is determined, and must be matched by the power output of the user. The efficiency of propulsion is the ratio of this power output to the metabolic cost and is typically in the order of 5% in normal use. The features required in a wheelchair depend upon user characteristics and intended activities. The ideal wheelchair for an individual will have the features that closely match these characteristics and activities. Thus prescription is not just choosing a wheelchair, but choosing the components of the wheelchair that best serve the intended purpose. In this paper, each component is examined for available options and how these options effect the performance of the wheelchair for the individual. The components include wheels, tyres, castors, frames, bearings, materials, construction details, seats, backrests, armrests, foot and legrests, headrests, wheel locks, running brakes, handrims, levers, accessories, adjustments and detachable parts. Each component is considered in relation to performance characteristics including rolling resistance, versatility, weight, comfort, stability, maneouvrability, transfer, stowage, durability and maintenance. Where they exist, wheelchair standards are referred to as a source of information regarding these characteristics.

  5. Electronic tongue: An analytical gustatory tool

    Directory of Open Access Journals (Sweden)

    Rewanthwar Swathi Latha

    2012-01-01

    Full Text Available Taste is an important organoleptic property governing acceptance of products for administration through mouth. But majority of drugs available are bitter in taste. For patient acceptability and compliance, bitter taste drugs are masked by adding several flavoring agents. Thus, taste assessment is one important quality control parameter for evaluating taste-masked formulations. The primary method for the taste measurement of drug substances and formulations is by human panelists. The use of sensory panelists is very difficult and problematic in industry and this is due to the potential toxicity of drugs and subjectivity of taste panelists, problems in recruiting taste panelists, motivation and panel maintenance are significantly difficult when working with unpleasant products. Furthermore, Food and Drug Administration (FDA-unapproved molecules cannot be tested. Therefore, analytical taste-sensing multichannel sensory system called as electronic tongue (e-tongue or artificial tongue which can assess taste have been replacing the sensory panelists. Thus, e-tongue includes benefits like reducing reliance on human panel. The present review focuses on the electrochemical concepts in instrumentation, performance qualification of E-tongue, and applications in various fields.

  6. Electronic tongue: An analytical gustatory tool.

    Science.gov (United States)

    Latha, Rewanthwar Swathi; Lakshmi, P K

    2012-01-01

    Taste is an important organoleptic property governing acceptance of products for administration through mouth. But majority of drugs available are bitter in taste. For patient acceptability and compliance, bitter taste drugs are masked by adding several flavoring agents. Thus, taste assessment is one important quality control parameter for evaluating taste-masked formulations. The primary method for the taste measurement of drug substances and formulations is by human panelists. The use of sensory panelists is very difficult and problematic in industry and this is due to the potential toxicity of drugs and subjectivity of taste panelists, problems in recruiting taste panelists, motivation and panel maintenance are significantly difficult when working with unpleasant products. Furthermore, Food and Drug Administration (FDA)-unapproved molecules cannot be tested. Therefore, analytical taste-sensing multichannel sensory system called as electronic tongue (e-tongue or artificial tongue) which can assess taste have been replacing the sensory panelists. Thus, e-tongue includes benefits like reducing reliance on human panel. The present review focuses on the electrochemical concepts in instrumentation, performance qualification of E-tongue, and applications in various fields.

  7. Biomechanics of the thorax - research evidence and clinical expertise.

    Science.gov (United States)

    Lee, Diane Gail

    2015-07-01

    Understanding the biomechanics of the thorax is critical for understanding its role in multiple conditions since the thorax is part of many integrated systems including the musculoskeletal, respiratory, cardiac, digestive and urogynecological. The thorax is also an integrated system within itself and an element of the whole body/person. Therefore, understanding the biomechanics of the thorax is fundamental to all forms of treatment for multiple conditions. The interpretation of movement examination findings depends on one's view of optimal biomechanics and the influential factors. This article will provide a synopsis of the current state of research evidence as well as observations from clinical experience pertaining to the biomechanics of the thorax in order to help clinicians organise this knowledge and facilitate evidence-based and informed management of the, often complex, patient with or without thoracic pain and impairment. The integrated systems model (ISM) will be introduced as a way to determine when the noted biomechanical findings are relevant to a patient's clinical presentation.

  8. Biomechanical analysis of rollator walking

    DEFF Research Database (Denmark)

    Alkjaer, T; Larsen, Peter K; Pedersen, Gitte

    2006-01-01

    The rollator is a very popular walking aid. However, knowledge about how a rollator affects the walking patterns is limited. Thus, the purpose of the study was to investigate the biomechanical effects of walking with and without a rollator on the walking pattern in healthy subjects.......The rollator is a very popular walking aid. However, knowledge about how a rollator affects the walking patterns is limited. Thus, the purpose of the study was to investigate the biomechanical effects of walking with and without a rollator on the walking pattern in healthy subjects....

  9. The geometry of resonance tongues : a singularity theory approach

    NARCIS (Netherlands)

    Broer, Hendrik; Golubitsky, Martin; Vegter, Gert

    2003-01-01

    Resonance tongues and their boundaries are studied for nondegenerate and (certain) degenerate Hopf bifurcations of maps using singularity theory methods of equivariant contact equivalence and universal unfoldings. We recover the standard theory of tongues (the nondegencrate case) in a straightforwar

  10. Tongue-Driven Wheelchair Out-Maneuvers the Competition

    Science.gov (United States)

    ... 496-3500 Share Science Highlight: January 2, 2014 Tongue-Driven Wheelchair Out-Maneuvers the Competition Researchers funded ... Imaging and Bioengineering have demonstrated that their novel Tongue Drive System is superior to other assistive devices ...

  11. Schwannoma of the base of tongue – A rare presentation

    Directory of Open Access Journals (Sweden)

    M. Panduranga Kamath

    2014-03-01

    Conclusion: Schwannomas arising in the base of tongue are rare and are not often included in the differential diagnosis. They are usually benign and have excellent prognosis as compared to the usual malignant lesions which occur in the tongue base.

  12. Isolated tongue tremor after gamma knife radiosurgery for acoustic schwannoma.

    Science.gov (United States)

    Chung, Sun J; Im, Joo-Hyuk; Lee, Jae-Hong; Cho, A-Hyun; Kwon, Miseon; Lee, Myoung C

    2005-01-01

    We describe a patient who had an isolated tongue tremor with an audible click after gamma knife radiosurgery for acoustic schwannoma. The nature of the tongue tremor was clearly demonstrated by videofluoroscopy. The possible pathogenic mechanisms are discussed.

  13. Three-dimensional tori and Arnold tongues

    Energy Technology Data Exchange (ETDEWEB)

    Sekikawa, Munehisa, E-mail: sekikawa@cc.utsunomiya-u.ac.jp [Department of Mechanical and Intelligent Engineering, Utsunomiya University, Utsunomiya-shi 321-8585 (Japan); Inaba, Naohiko [Organization for the Strategic Coordination of Research and Intellectual Property, Meiji University, Kawasaki-shi 214-8571 (Japan); Kamiyama, Kyohei [Department of Electronics and Bioinformatics, Meiji University, Kawasaki-shi 214-8571 (Japan); Aihara, Kazuyuki [Institute of Industrial Science, the University of Tokyo, Meguro-ku 153-8505 (Japan)

    2014-03-15

    This study analyzes an Arnold resonance web, which includes complicated quasi-periodic bifurcations, by conducting a Lyapunov analysis for a coupled delayed logistic map. The map can exhibit a two-dimensional invariant torus (IT), which corresponds to a three-dimensional torus in vector fields. Numerous one-dimensional invariant closed curves (ICCs), which correspond to two-dimensional tori in vector fields, exist in a very complicated but reasonable manner inside an IT-generating region. Periodic solutions emerge at the intersections of two different thin ICC-generating regions, which we call ICC-Arnold tongues, because all three independent-frequency components of the IT become rational at the intersections. Additionally, we observe a significant bifurcation structure where conventional Arnold tongues transit to ICC-Arnold tongues through a Neimark-Sacker bifurcation in the neighborhood of a quasi-periodic Hopf bifurcation (or a quasi-periodic Neimark-Sacker bifurcation) boundary.

  14. Progress of Biomimetic Artificial Nose and Tongue

    Science.gov (United States)

    Wang, Ping; Liu, Qingjun

    2009-05-01

    As two of the basic senses of human beings, olfaction and gustation play a very important role in daily life. These two types of chemical sensors are important for recognizing environmental conditions. Electronic nose and electronic tongue, which mimics animals' olfaction and gustation to detect odors and chemical components, have been carried out due to their potential commercial applications for biomedicine, food industry and environmental protection. In this report, the biomimetic artificial nose and tongue is presented. Firstly, the smell and taste sensors mimicking the mammalian olfaction and gustation was described, and then, some mimetic design of electronic nose and tongue for odorants and tastants detection are developed. Finally, olfactory and gustatory biosensors are presented as the developing trends of this field.

  15. Stimulating effect of tongue on craniofacial growth.

    Science.gov (United States)

    Schumacher, G H; Becker, R; Hübner, A; Pommerenke, F

    1991-01-01

    The influence of the tongue on craniofacial growth was studied in 96 Mini-Lewe miniature pigs. The animals were partially glossectomized at different ages and slaughtered at various intervals after operation. The skulls were macerated for biometric analysis. Mandibular growth was significantly reduced lengthwise in animals glossectomized at age 12 weeks. The role played by the tongue in orofacial growth was also indicated by the reduced width of the lower jaw. In pigs partially glossectomized at age 12 weeks, lateral growth of the entire lower jaw was reduced after eight weeks. In animals glossectomized at age six weeks, lateral growth of the lower jaw was reduced in the region of the 1st deciduous molars and the canines after glossectomy. Partial glossectomy had no significant effects on vertical growth of the lower jaw, growth of the upper jaw or overall skull growth. Shortening of the tongue in miniature pigs six weeks old resulted in no measurable jaw changes 23 weeks after surgery.

  16. Undulating tongue in Wilson′s disease

    Directory of Open Access Journals (Sweden)

    M Nagappa

    2014-01-01

    Full Text Available We report an unusual occurrence of involuntary movement involving the tongue in a patient with confirmed Wilson′s disease (WD. She manifested with slow, hypophonic speech and dysphagia of 4 months duration, associated with pseudobulbar affect, apathy, drooling and dystonia of upper extremities of 1 month duration. Our patient had an uncommon tongue movement which was arrhythmic. There was no feature to suggest tremor, chorea or dystonia. It might be described as athetoid as there was a writhing quality, but of lesser amplitude. Thus, the phenomenology was uncommon in clinical practice and the surface of the tongue was seen to "ripple" like a liquid surface agitated by an object or breeze. Isolated lingual dyskinesias are rare in WD. It is important to evaluate them for WD, a potentially treatable disorder.

  17. The Tongue as an Excitable Medium

    CERN Document Server

    Seiden, Gabriel

    2014-01-01

    Geographic tongue (GT) is a benign condition affecting approximately 2% of the population, whereby the papillae covering the upper part of the tongue are lost due to a slowly expanding inflammation. The resultant dynamical appearance of the tongue has striking similarities with well known phenomena observed in excitable media, such as forest fires, cardiac dynamics and chemically-driven reaction-diffusion systems. Here we explore the dynamics associated with GT from a dynamical systems perspective, utilizing cellular automata simulations. We emphasize similarities with other excitable systems as well as unique features observed in GT. Our results shed light on the evolution of the inflammation and contribute to the classification of the severity of the condition, based on the characteristic patterns observed in GT patients.

  18. Characterization of Chinese rice wine taste attributes using liquid chromatographic analysis, sensory evaluation, and an electronic tongue.

    Science.gov (United States)

    Yu, HaiYan; Zhao, Jie; Li, Fenghua; Tian, Huaixiang; Ma, Xia

    2015-08-01

    To evaluate the taste characteristics of Chinese rice wine, wine samples sourced from different vintage years were analyzed using liquid chromatographic analysis, sensory evaluation, and an electronic tongue. Six organic acids and seventeen amino acids were measured using high performance liquid chromatography (HPLC). Five monosaccharides were measured using anion-exchange chromatography. The global taste attributes were analyzed using an electronic tongue (E-tongue). The correlations between the 28 taste-active compounds and the sensory attributes, and the correlations between the E-tongue response and the sensory attributes were established via partial least square discriminant analysis (PLSDA). E-tongue response data combined with linear discriminant analysis (LDA) were used to discriminate the Chinese rice wine samples sourced from different vintage years. Sensory evaluation indicated significant differences in the Chinese rice wine samples sourced from 2003, 2005, 2008, and 2010 vintage years in the sensory attributes of harmony and mellow. The PLSDA model for the taste-active compounds and the sensory attributes showed that proline, fucose, arabinose, lactic acid, glutamic acid, arginine, isoleucine, valine, threonine, and lysine had an influence on the taste characteristic of Chinese rice wine. The Chinese rice wine samples were all correctly classified using the E-tongue and LDA. The electronic tongue was an effective tool for rapid discrimination of Chinese rice wine.

  19. Integrated biomechanical and topographical surface characterization (IBTSC)

    Science.gov (United States)

    Löberg, Johanna; Mattisson, Ingela; Ahlberg, Elisabet

    2014-01-01

    In an attempt to reduce the need for animal studies in dental implant applications, a new model has been developed which combines well-known surface characterization methods with theoretical biomechanical calculations. The model has been named integrated biomechanical and topographical surface characterization (IBTSC), and gives a comprehensive description of the surface topography and the ability of the surface to induce retention strength with bone. IBTSC comprises determination of 3D-surface roughness parameters by using 3D-scanning electron microscopy (3D-SEM) and atomic force microscopy (AFM), and calculation of the ability of different surface topographies to induce retention strength in bone by using the local model. Inherent in this integrated approach is the use of a length scale analysis, which makes it possible to separate different size levels of surface features. The IBTSC concept is tested on surfaces with different level of hierarchy, induced by mechanical as well as chemical treatment. Sequential treatment with oxalic and hydrofluoric acid results in precipitated nano-sized features that increase the surface roughness and the surface slope on the sub-micro and nano levels. This surface shows the highest calculated shear strength using the local model. The validity, robustness and applicability of the IBTSC concept are demonstrated and discussed.

  20. Integrated biomechanical and topographical surface characterization (IBTSC)

    Energy Technology Data Exchange (ETDEWEB)

    Löberg, Johanna, E-mail: Johanna.Loberg@dentsply.com [Dentsply Implants, Box 14, SE-431 21 Mölndal (Sweden); Mattisson, Ingela [Dentsply Implants, Box 14, SE-431 21 Mölndal (Sweden); Ahlberg, Elisabet [Department of Chemistry and Molecular Biology, University of Gothenburg, SE-41296 Gothenburg (Sweden)

    2014-01-30

    In an attempt to reduce the need for animal studies in dental implant applications, a new model has been developed which combines well-known surface characterization methods with theoretical biomechanical calculations. The model has been named integrated biomechanical and topographical surface characterization (IBTSC), and gives a comprehensive description of the surface topography and the ability of the surface to induce retention strength with bone. IBTSC comprises determination of 3D-surface roughness parameters by using 3D-scanning electron microscopy (3D-SEM) and atomic force microscopy (AFM), and calculation of the ability of different surface topographies to induce retention strength in bone by using the local model. Inherent in this integrated approach is the use of a length scale analysis, which makes it possible to separate different size levels of surface features. The IBTSC concept is tested on surfaces with different level of hierarchy, induced by mechanical as well as chemical treatment. Sequential treatment with oxalic and hydrofluoric acid results in precipitated nano-sized features that increase the surface roughness and the surface slope on the sub-micro and nano levels. This surface shows the highest calculated shear strength using the local model. The validity, robustness and applicability of the IBTSC concept are demonstrated and discussed.

  1. Infrahyoid myofascial flap for tongue reconstruction.

    Science.gov (United States)

    Windfuhr, Jochen P; Remmert, Stephan

    2006-11-01

    For selected cases, reconstruction of the tongue may be required after tumor removal. This study was undertaken to demonstrate a simplified concept of tongue reconstruction with emphasis on infrahyoid myofascial flaps (IMF). The defects of the tongue were classified in 23 patients according to the extent of tumor growth, functional and surgical aspects. The oral tongue (OT; n = 1), base of tongue (BT; n = 12) or both areas (OT and BT; n = 10) were involved, with (n = 14) or without (n = 9) infiltration of adjacent tissues. Minor defects (extent (1/4) or less) required no reconstructive procedure at any area. Major defect closure (extent (1/2)-3/4) was accomplished with a combination of IMF covered by a radial forearm flap (RFF). A complete reconstruction of the OT was achieved with a combination of a bilateral IMF covered by a RFF. Whenever the complete BT has to be removed, interposition of a vein graft to establish a sufficient arterial blood supply to the remaining OT is mandatory. Moreover, a larynx lift to prevent aspiration is recommendable. Resection of adjacent soft tissues requires a larger RFF (OT; BT) or flaps from the shoulder-back region (BT and OT). Whenever the integrity of the mandible has to be sacrificed, a free fibula graft serves as an excellent tool for reconstruction. IMF serves as a reliable tool for minor or major reconstructive procedures of the tongue. Reliability and versatility of IMF may contribute to a reduced time required for surgery since harvesting is performed in the neck area immediately after neck dissection. Moreover, harvesting of the IMF does not result in an increased postoperative morbidity. Hence, functional restoration can be achieved with a more cost-effective procedure.

  2. Sensory evaluation and electronic tongue for sensing flavored mineral water taste attributes.

    Science.gov (United States)

    Sipos, László; Gere, Attila; Szöllősi, Dániel; Kovács, Zoltán; Kókai, Zoltán; Fekete, András

    2013-10-01

    In this article a trained sensory panel evaluated 6 flavored mineral water samples. The samples consisted of 3 different brands, each with 2 flavors (pear-lemon grass and josta berry). The applied sensory method was profile analysis. Our aim was to analyze the sensory profiles and to investigate the similarities between the sensitivity of the trained human panel and an electronic tongue device. Another objective was to demonstrate the possibilities for the prediction of sensory attributes from electronic tongue measurements using a multivariate statistical method (Partial Least Squares regression [PLS]). The results showed that the products manufactured under different brand name but with the same aromas had very similar sensory profiles. The panel performance evaluation showed that it is appropriate (discrimination ability, repeatability, and panel consensus) to compare the panel's results with the results of the electronic tongue. The samples can be discriminated by the electronic tongue and an accurate classification model can be built. Principal Component Analysis BiPlot diagrams showed that Brand A and B were similar because the manufacturers use the same aroma brands for their products. It can be concluded that Brand C was quite different compared to the other samples independently of the aroma content. Based on the electronic tongue results good prediction models can be obtained with high correlation coefficient (r(2) > 0.81) and low prediction error (RMSEP < 13.71 on the scale of the sensory evaluation from 0 to 100).

  3. [Comparative imaging of cancers of the tongue].

    Science.gov (United States)

    Maradji-Melia, P; Bruneton, J N; Balu-Maestro, C; Marcy, P Y; Dubruque, F; Dassonville, O

    1993-05-01

    In a comparative study of 18 cases of tongue cancer examined with ultrasonography, computed tomography (CT) and magnetic resonance imaging (MRI), the authors assess the advantages and disadvantages of each technique. MRI seems to be more effective for the detection of small lesions, the examination of the mobile part of the tongue, in case of dental artifacts, for the study of regional extension and to screen recurrence. CT retains its indications for large tumors in patients who are in a poor general condition, tired, and cannot stand lengthy examinations. Ultrasonography remains the first-intention examination in all cases because of its indisputable superiority for lymph node examination.

  4. Lingual neurofibroma causing dysaesthesia of the tongue

    DEFF Research Database (Denmark)

    Lykke, Eva; Nørgaard, Tove; Rye Rasmussen, Eva

    2013-01-01

    of otorhinolaryngology with irritation and dysaesthesia of the lateral aspect of the tongue. The only finding was a slightly red area from which a biopsy was taken. The macroscopic findings observed by the surgeon were consistent with normal tongue tissue. The histopathological examination showed a small, rounded tumour...... closely approximated to an invagination of the surface epithelium and with a small lymphatic infiltrate. The tumour was a neurofibroma. A Schwannoma type B was considered but the presence of small nerves and positive neurofilament reaction favoured a neurofibroma. The patient had no other neurofibromas...

  5. Tongues in degree 4 Blaschke products

    Science.gov (United States)

    Canela, Jordi; Fagella, Núria; Garijo, Antonio

    2016-11-01

    The goal of this paper is to investigate the family of Blasche products {{B}a}(z)={{z}3}\\frac{z-a}{1-\\bar{a}z} , which is a rational family of perturbations of the doubling map. We focus on the tongue-like sets which appear in its parameter plane. We first study their basic topological properties and afterwards we investigate how bifurcations take place in a neighborhood of their tips. Finally we see how the fixed tongue extends beyond its natural domain of definition.

  6. Schwannoma of the tongue: one case report.

    Science.gov (United States)

    Mevio, E; Gorini, E; Lenzi, A; Migliorini, L

    2002-01-01

    The schwannomas are nervous tissue tumours that arise from Schwann cells; they are uncommon in peripheral nerves and rare in the tongue. After, a review of the literature, we present a case of schwannoma which arose in the ventral part of the body of the tongue. The tumour presented as a slowly growing mass producing few symptoms. The diagnosis of schwannoma is usually made post-operatively by histological identification although modern imaging techniques can provide useful indications. The treatment is exclusively surgical and usually enucleation of the mass is uncomplicated. There are no reports of malignant transformation.

  7. SCHWANNOMA OF THE TONGUE - A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Satyananda Rao

    2013-11-01

    Full Text Available ABSTRACT: A case report of an 18 - year - old young girl presented with a slow - growing, painless swelling on the right side of the tongue since 4 years. This was associated with disturbances in mastication. Examination revealed a 3 cm x 4 cm, globular smooth, mobile mass on right side of the tongue. There was no neurological deficit and no neck nodes palpable. She underwent excision of the mass under general anaesthesia. Complete enucleation with primary closure was carried out. The patient had an uneventful postoperative recovery and histo patho logical evaluation was consistent with schwannoma. The patient is recurrence free till date

  8. The biomechanical and structural properties of CS2 fimbriae

    CERN Document Server

    Mortezaei, Narges; Zakrisson, Johan; Bullitt, Esther; Andersson, Magnus

    2015-01-01

    Enterotoxigenic Escherichia coli (ETEC) are a major cause of diarrhea worldwide, and infection of children in underdeveloped countries often leads to high mortality rates. Isolated ETEC express a plethora of colonization factors (fimbriae/pili), of which CFA/I and CFA/II that are assembled via the alternate chaperone pathway (ACP), are amongst the most common. Fimbriae are filamentous structures, whose shafts are primarily composed of helically arranged single pilin-protein subunits, with a unique biomechanical capability allowing them to unwind and rewind. A sustained ETEC infection, under adverse conditions of dynamic shear forces, is primarily attributed to this biomechanical feature of ETEC fimbriae. Recent understandings about the role of fimbriae as virulence factors are pointing to an evolutionary adaptation of their structural and biomechanical features. In this work, we investigated the biophysical properties of CS2 fimbriae from the CFA/II group. Homology modelling its major structural subunit CotA ...

  9. Biomechanical analysis technique choreographic movements (for example, "grand battman jete"

    Directory of Open Access Journals (Sweden)

    Batieieva N.P.

    2015-04-01

    Full Text Available Purpose : biomechanical analysis of the execution of choreographic movement "grand battman jete". Material : the study involved students (n = 7 of the department of classical choreography faculty of choreography. Results : biomechanical analysis of choreographic movement "grand battman jete" (classic exercise, obtained kinematic characteristics (path, velocity, acceleration, force of the center of mass (CM bio parts of the body artist (foot, shin, thigh. Built bio kinematic model (phase. The energy characteristics - mechanical work and kinetic energy units legs when performing choreographic movement "grand battman jete". Conclusions : It was found that the ability of an athlete and coach-choreographer analyze the biomechanics of movement has a positive effect on the improvement of choreographic training of qualified athletes in gymnastics (sport, art, figure skating and dance sports.

  10. Biomechanics of metastatic disease in the vertebral column.

    Science.gov (United States)

    Whyne, Cari M

    2014-06-01

    Metastatic disease in the vertebral column compromises the structural stability of the spine leading to increased risk of fracture. The complex patterns of osteolytic and osteoblastic disease within the bony spine have motivated a multimodal approach to better characterize the biomechanics of tumor-involved bone. This review presents our current understanding of the biomechanical behavior of metastatically involved vertebrae, and experimental and computational image-based approaches that have been employed to quantify structural integrity in preclinical models with translation to clinical data sets.

  11. Evidence for an elastic projection mechanism in the chameleon tongue

    NARCIS (Netherlands)

    Groot, de J.H.; Leeuwen, van J.L.

    2004-01-01

    To capture prey, chameleons ballistically project their tongues as far as 1.5 body lengths with accelerations of up to 500 m s-2. At the core of a chameleon's tongue is a cylindrical tongue skeleton surrounded by the accelerator muscle. Previously, the cylindrical accelerator muscle was assumed to p

  12. Tongue Control and Its Implication in Pronunciation Training

    Science.gov (United States)

    Ouni, Slim

    2014-01-01

    Pronunciation training based on speech production techniques illustrating tongue movements is gaining popularity. However, there is not sufficient evidence that learners can imitate some tongue animation. In this paper, we argue that although controlling tongue movement related to speech is not such an easy task, training with visual feedback…

  13. Apc-Mutant Kyoto Apc Delta (KAD) Rats Are Susceptible to 4-NQO-Induced Tongue Carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Takuji, E-mail: tmntt08@gmail.com [Department of Diagnostic Pathology (DDP) & Research Center of Diagnostic Pathology (RC-DiP), Gifu Municipal Hospital, 7-1 Kashima-Cho, Gifu 500-8513 (Japan); Department of Tumor Pathology, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu 501-1194 (Japan); Shimizu, Masahito; Kochi, Takahiro; Shirakami, Yohei [Department of Internal Medicine/Gastroenterology, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu 501-1194 (Japan); Mori, Takayuki [Department of Pharmacy, Ogaki Municipal Hospital, 4-86 Minaminokawa-cho, Ogaki 503-8502 (Japan); Watanabe, Naoki [Department of Diagnostic Pathology (DDP) & Research Center of Diagnostic Pathology (RC-DiP), Gifu Municipal Hospital, 7-1 Kashima-Cho, Gifu 500-8513 (Japan); Naiki, Takafumi [Department of Clinical Laboratory, Gifu Municipal Hospital, 7-1 Kashima-cho, Gifu 500-8513 (Japan); Moriwaki, Hisataka [Department of Internal Medicine/Gastroenterology, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu 501-1194 (Japan); Yoshimi, Kazuto; Serikawa, Tadao; Kuramoto, Takashi [The Institute of Laboratory Animals, Graduate School of Medicine, Kyoto University, Yoshidakonoe-cho, Sakyo-ku, Kyoto 606-8501 (Japan)

    2014-07-21

    Despite widening interest in the possible association between infection/inflammation and cancer development, knowledge of this issue in relation to oral cancer remains inadequate. This study aimed to determine the susceptibility of Apc-mutant Kyoto Apc Delta (KAD) rats, which are vulnerable to developing inflammation-associated colorectal carcinogenesis, to 4-nitroquinoline 1-oxide (4-NQO)-induced tongue carcinogenesis in order to clarify the role of inflammation in oral cancer. KAD (20 males and 22 females) and F344/NS1c (22 males and 23 females) rats received drinking water with or without 4-NQO (20 ppm) for eight weeks. Histopathological and immunohistochemical analyses of the tongue were performed at week 20. Additionally, the mRNA expression of inflammatory cytokines in the tongue mucosa was determined at week 8. Tongue squamous cell carcinoma (SCC) developed in the KAD and F344/NS1c rats that received 4-NQO. Regardless of gender, the incidence and multiplicity of tongue SCC were greater in the KAD rats than in the F344/NS1c rats. In addition, the multiplicity of tongue SCC in the female KAD rats was significantly greater than that observed in the male KAD (p < 0.01) and female F344/NS1c rats (p < 0.05). The levels of inflammation and the mRNA expression of inflammatory cytokines in the tongue in the 4-NQO-treated female KAD rats were the highest among the rats given 4-NQO. These results show that KAD rats, particularly females, are susceptible to 4-NQO-induced tongue carcinogenesis, suggesting the utility of models employing KAD rats for investigating the pathobiology of oral (tongue) carcinogenesis associated with inflammation.

  14. Apc-Mutant Kyoto Apc Delta (KAD Rats Are Susceptible to 4-NQO-Induced Tongue Carcinogenesis

    Directory of Open Access Journals (Sweden)

    Takuji Tanaka

    2014-07-01

    Full Text Available Despite widening interest in the possible association between infection/ inflammation and cancer development, knowledge of this issue in relation to oral cancer remains inadequate. This study aimed to determine the susceptibility of Apc-mutant Kyoto Apc Delta (KAD rats, which are vulnerable to developing inflammation-associated colorectal carcinogenesis, to 4-nitroquinoline 1-oxide (4-NQO-induced tongue carcinogenesis in order to clarify the role of inflammation in oral cancer. KAD (20 males and 22 females and F344/NS1c (22 males and 23 females rats received drinking water with or without 4-NQO (20 ppm for eight weeks. Histopathological and immunohistochemical analyses of the tongue were performed at week 20. Additionally, the mRNA expression of inflammatory cytokines in the tongue mucosa was determined at week 8. Tongue squamous cell carcinoma (SCC developed in the KAD and F344/NS1c rats that received 4-NQO. Regardless of gender, the incidence and multiplicity of tongue SCC were greater in the KAD rats than in the F344/NS1c rats. In addition, the multiplicity of tongue SCC in the female KAD rats was significantly greater than that observed in the male KAD (p < 0.01 and female F344/NS1c rats (p < 0.05. The levels of inflammation and the mRNA expression of inflammatory cytokines in the tongue in the 4-NQO-treated female KAD rats were the highest among the rats given 4-NQO. These results show that KAD rats, particularly females, are susceptible to 4-NQO-induced tongue carcinogenesis, suggesting the utility of models employing KAD rats for investigating the pathobiology of oral (tongue carcinogenesis associated with inflammation.

  15. Clinical applications of biomechanics cinematography.

    Science.gov (United States)

    Woodle, A S

    1986-10-01

    Biomechanics cinematography is the analysis of movement of living organisms through the use of cameras, image projection systems, electronic digitizers, and computers. This article is a comparison of cinematographic systems and details practical uses of the modality in research and education.

  16. 一个三维人膝关节弹性咬合的生物力学模型%A 3-D BIOMECHANICAL MODEL OF HUMAN KNEE JOINT ELASTICALLY ARTICULATE CONTACT

    Institute of Scientific and Technical Information of China (English)

    王西十; 王珉

    2000-01-01

    Based on the characterizations of human knee-joint anatomical structures and reports of the literature and experiments, a 3-D biomechanical model of the human knee-joint elastically articulate contact is developed under the conditions of sampling the human knee-joints. This model is believed to be a powerful tool for functional analysis of the knee, for evaluation of surgical and diagnostic procedures and for design of artificial joints.%基于人膝关节的解剖特征,在文献和试验的基础上,对膝关节解剖结构作了适当的简化,从而建立了一个完整的三维人膝关节弹性咬合的生物力学模型.

  17. A Normative-Speaker Validation Study of Two Indices Developed to Quantify Tongue Dorsum Activity from Midsagittal Tongue Shapes

    Science.gov (United States)

    Zharkova, Natalia

    2013-01-01

    This study reported adult scores on two measures of tongue shape, based on midsagittal tongue shape data from ultrasound imaging. One of the measures quantified the extent of tongue dorsum excursion, and the other measure represented the place of maximal excursion. Data from six adult speakers of Scottish Standard English without speech disorders…

  18. Tongue controlled computer game: A new approach for rehabilitation of tongue motor function

    DEFF Research Database (Denmark)

    Kothari, Mohit; Svensson, Peter; Jensen, Jim

    2014-01-01

    Objective: To investigate the influence of tongue-disability, age and gender on motor performance for a tongue training paradigm involving playing a computer game using the Tongue Drive System (TDS). Design: Two controlled observational studies. Setting: A neurorehabilitation center and a dental...... training lasted 30 min and 40 min respectively. The participants were instructed to play a computer game with the tongue using TDS. Main Outcome Measures: Motor performance was compared between groups in both studies. Correlation analyses were performed between age and relative improvement in performance...... young participants performed better than healthy elderly (Peffect of gender (P=0.140). There was a significant negative correlation between age and relative improvement in performance (δ=-0.450, P=0.009). There were no significant differences in subject-based reports...

  19. Biomechanics of sport concussion: quest for the elusive injury threshold.

    Science.gov (United States)

    Guskiewicz, Kevin M; Mihalik, Jason P

    2011-01-01

    Previous concussion biomechanics research has relied heavily on the animal model or laboratory reconstruction of concussive injuries captured on video footage. Real-time data collection involves a novel approach to better understanding the medical issues related to sport concussion. Recent studies suggest that a concussive injury threshold is elusive and may, in fact, be irrelevant when predicting the clinical outcome.

  20. Computational Biomechanics of Human Red Blood Cells in Hematological Disorders.

    Science.gov (United States)

    Li, Xuejin; Li, He; Chang, Hung-Yu; Lykotrafitis, George; Em Karniadakis, George

    2017-02-01

    We review recent advances in multiscale modeling of the biomechanical characteristics of red blood cells (RBCs) in hematological diseases, and their relevance to the structure and dynamics of defective RBCs. We highlight examples of successful simulations of blood disorders including malaria and other hereditary disorders, such as sickle-cell anemia, spherocytosis, and elliptocytosis.

  1. Pre and post 1997/1998 Westerly Wind Events and equatorial Pacific cold tongue warming

    Science.gov (United States)

    Harrison, D. E.; Chiodi, A. M.

    2008-12-01

    Westerly Wind Events (WWEs) in the western equatorial Pacific have previously been shown to cause significant warming of sea surface temperature (SST) in the eastern equatorial Pacific. Observational statistics compiled during and prior to the large El Nino event of 1997/1998 link WWEs to substantial (up to 3C) warming in the eastern Pacific cold-tongue region. Since 1998, however, relatively little WWE-related cold tongue warming has been observed and warm equatorial Pacific SST anomalies (SSTAs) have tended to be trapped near the dateline rather than extending to the American coast as in a classical El Nino-Southern Oscillation (ENSO) composite. Here, we revisit the relationship between WWEs and cold-tongue warming using in situ and operational forecast winds and in situ and satellite-based SST. We find significant differences in the basin scale zonal wind anomalies associated with WWEs that occurred before and after 1997/1998. Although the post 1997/1998 composite WWE westerly anomalies are very similar to their predecessors within the WWE regions, conditions east of the WWE regions are different; there are enhanced equatorial easterlies in the post 1997/1998 cases. General ocean circulation model experiments are conducted to explore the extent to which the observed changes in the character of post 1997/1998 WWEs can explain the recent behavior of cold tongue SSTAs. We find that the wind differences can account for the changes in the average cold tongue warming associated with pre and post 1997/1998 WWEs.

  2. Peritoneal mesothelioma metastasis to the tongue – Comparison with 8 pleural mesothelioma reports with tongue metastases

    Directory of Open Access Journals (Sweden)

    Melisa V. Vazquez

    2016-02-01

    Conclusions: Metastasis of MM to the tongue is rare and usually in the uncommon context of MM with multiple sites of extra-thoracic or extra-abdominal spread. We have described a unique clinical manifestation of a rare subtype of mesothelioma. Moreover, we have tabulated and summarised details (including responses to surgery or/and radiotherapy regarding all reported cases of mesotheliomas with tongue metastasis.

  3. The Tongue Map, Real or Not?

    Science.gov (United States)

    Marshall, Pamela A.

    2013-01-01

    Students need practice in proposing hypotheses, developing experiments that will test these hypotheses, and generating data that they will analyze to support or refute them. I describe a guided-inquiry activity based on the "tongue map" concept, appropriate for middle school and high school students.

  4. Ground-Tracking With a Forked Tongue

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    Scientists since Aristotle’s day have wondered why the tongues of snakes and many lizards——are forked, a trait that dates from at least the Cretaceous,more than 65 million years ago.Now Kurt Schwenk,a University of Connecticut evolutionary biologist, thinks he knows the answer. "It gives them the abil-

  5. Acute dystonia mimicking angioedema of the tongue

    DEFF Research Database (Denmark)

    Rasmussen, Eva Rye; Pallesen, Kristine A U; Bygum, Anette

    2013-01-01

    We report a case of acute dystonia of the face, jaw and tongue caused by metoclopramide and mimicking angioedema. The patient had attacks for several years before the correct diagnosis was made and we present the first ever published video footage of an attack. This adverse drug reaction is known...

  6. Inelastic mechanics: A unifying principle in biomechanics.

    Science.gov (United States)

    Gralka, Matti; Kroy, Klaus

    2015-11-01

    Many soft materials are classified as viscoelastic. They behave mechanically neither quite fluid-like nor quite solid-like - rather a bit of both. Biomaterials are often said to fall into this class. Here, we argue that this misses a crucial aspect, and that biomechanics is essentially damage mechanics, at heart. When deforming an animal cell or tissue, one can hardly avoid inducing the unfolding of protein domains, the unbinding of cytoskeletal crosslinkers, the breaking of weak sacrificial bonds, and the disruption of transient adhesions. We classify these activated structural changes as inelastic. They are often to a large degree reversible and are therefore not plastic in the proper sense, but they dissipate substantial amounts of elastic energy by structural damping. We review recent experiments involving biological materials on all scales, from single biopolymers over cells to model tissues, to illustrate the unifying power of this paradigm. A deliberately minimalistic yet phenomenologically very rich mathematical modeling framework for inelastic biomechanics is proposed. It transcends the conventional viscoelastic paradigm and suggests itself as a promising candidate for a unified description and interpretation of a wide range of experimental data. This article is part of a Special Issue entitled: Mechanobiology.

  7. ERK-GluR1 phosphorylation in trigeminal spinal subnucleus caudalis neurons is involved in pain associated with dry tongue

    Science.gov (United States)

    Nakaya, Yuka; Tsuboi, Yoshiyuki; Okada-Ogawa, Akiko; Shinoda, Masamichi; Kubo, Asako; Chen, Jui Yen; Noma, Noboru; Batbold, Dulguun; Imamura, Yoshiki; Sessle, Barry J

    2016-01-01

    Background Dry mouth is known to cause severe pain in the intraoral structures, and many dry mouth patients have been suffering from intraoral pain. In development of an appropriate treatment, it is crucial to study the mechanisms underlying intraoral pain associated with dry mouth, yet the detailed mechanisms are not fully understood. To evaluate the mechanisms underlying pain related to dry mouth, the dry-tongue rat model was developed. Hence, the mechanical or heat nocifensive reflex, the phosphorylated extracellular signal-regulated kinase and phosphorylated GluR1-IR immunohistochemistries, and the single neuronal activity were examined in the trigeminal spinal subnucleus caudalis of dry-tongue rats. Results The head-withdrawal reflex threshold to mechanical, but not heat, stimulation of the tongue was significantly decreased on day 7 after tongue drying. The mechanical, but not heat, responses of trigeminal spinal subnucleus caudalis nociceptive neurons were significantly enhanced in dry-tongue rats compared to sham rats on day 7. The number of phosphorylated extracellular signal-regulated kinase-immunoreactive cells was also significantly increased in the trigeminal spinal subnucleus caudalis following noxious stimulation of the tongue in dry-tongue rats compared to sham rats on day 7. The decrement of the mechanical head-withdrawal reflex threshold (HWT) was reversed during intracisternal administration of the mitogen-activated protein kinase kinase 1 inhibitor, PD98059. The trigeminal spinal subnucleus caudalis neuronal activities and the number of phosphorylated extracellular signal-regulated kinase-immunoreactive cells following noxious mechanical stimulation of dried tongue were also significantly decreased following intracisternal administration of PD98059 compared to vehicle-administrated rats. Increased number of the phosphorylated GluR1-IR cells was observed in the trigeminal spinal subnucleus caudalis of dry-tongue rats, and the number of

  8. ADIEU TO TONGUE TIE. LINGUAL FRENECTOMY: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Rizwan Sanadi

    2013-07-01

    Full Text Available A Frenum is a fold of mucous membrane, usually with enclosed muscle fibers, that attaches the lips and cheeks to the alveolar mucosa and/or mucosa and underlying periosteum. Tongue tie or ankyloglossia is a developmental anomaly of the tongue characterized by an abnormally short, thick lingual frenum resulting in limitation of tongue movement. It causes difficulty in speech articulation due to limitation in tongue movement. In this article we report a case of 24 years old female with Tongue tie, complaining of difficulty in speech. It was surgically treated with uneventful healing and good patient satisfaction.

  9. Biomechanics of knee joint — A review

    Science.gov (United States)

    Madeti, Bhaskar Kumar; Chalamalasetti, Srinivasa Rao; Bolla Pragada, S. K. Sundara siva rao

    2015-06-01

    The present paper is to know how the work is carried out in the field of biomechanics of knee. Various model formulations are discussed and further classified into mathematical model, two-dimensional model and three-dimensional model. Knee geometry is a crucial part of human body movement, in which how various views of knee is shown in different planes and how the forces act on tibia and femur are studied. It leads to know the forces acting on the knee joint. Experimental studies of knee geometry and forces acting on knee shown by various researchers have been discussed, and comparisons of results are made. In addition, static and dynamic analysis of knee has been also discussed respectively to some extent.

  10. Availability of Tongue Diagnosis System for Assessing Tongue Coating Thickness in Patients with Functional Dyspepsia

    Directory of Open Access Journals (Sweden)

    Juyeon Kim

    2013-01-01

    Full Text Available Tongue diagnosis is an important procedure in traditional Korean medicine (TKM. In particular, tongue coating thickness (TCT is deemed to show the progression of the disease. However, conventional tongue diagnosis has limitations because of various external factors. Therefore, it is necessary to investigate the availability of tongue diagnosis system (TDS in the assessment of TCT. This study has been designed as a prospective clinical trial involving 60 patients with functional dyspepsia. Tongue images will be obtained by TDS twice with a 30 min interval. The system will measure the percentage of TCT and classify it as either no coating, thin coating, or thick coating according to the existing diagnostic criteria. After finishing the collection of 60 patients' tongue images, TCT on the images will be simultaneously evaluated by the conventional method to establish the gold standard for assessing TCT by 5 well-trained clinicians. The evaluation will be repeated by the same clinicians after 2 weeks, but the order of the images will be changed. This trial is expected to provide clinical evidence for the availability of TDS as a diagnostic tool and to contribute to the standardization of the diagnosis system used in TKM. This trial is registered with ClinicalTrials.gov NCT01864837.

  11. Developmental biomechanics of the cervical spine: Tension and compression.

    Science.gov (United States)

    Nuckley, David J; Ching, Randal P

    2006-01-01

    Epidemiological data and clinical indicia reveal devastating consequences associated with pediatric neck injuries. Unfortunately, neither injury prevention nor clinical management strategies will be able to effectively reduce these injuries or their effects on children, without an understanding of the cervical spine developmental biomechanics. Thus, we investigated the relationship between spinal development and the functional (stiffness) and failure biomechanical characteristics of the cervical spine in a baboon model. A correlation study design was used to define the relationships between spinal tissue maturation and spinal biomechanics in both tension and compression. Eighteen baboon cervical spine specimens distributed across the developmental spectrum (1-26 human equivalent years) were dissected into osteoligamentous functional spinal units. Using a servo-hydraulic MTS, these specimens (Oc-C2, C3-C4, C5-C6, C7-T1) were non-destructively tested in tension and compression and then displaced to failure in tension while measuring the six-axes of loads and displacements. The functions describing the developmental biomechanical response of the cervical spine for stiffness and normalized stiffness exhibited a significant direct relationship in both tension and compression loading. Similarly, the tensile failure load and normalized failure load demonstrated significant maturational increases. Further, differences in biomechanical response were observed between the spinal levels examined and all levels exhibited clinically relevant failure patterns. These data support our understanding of the child cervical spine from a developmental biomechanics perspective and facilitate the development of injury prevention or management schema for the mitigation of child spine injuries and their deleterious effects.

  12. Parameters that effect spine biomechanics following cervical disc replacement.

    Science.gov (United States)

    Goel, Vijay K; Faizan, Ahmad; Palepu, Vivek; Bhattacharya, Sanghita

    2012-06-01

    Total disc replacement (TDR) is expected to provide a more physiologic alternative to fusion. However, long-term clinical data proving the efficacy of the implants is lacking. Limited clinical data suggest somewhat of a disagreement between the in vitro biomechanical studies and in vivo assessments. This conceptual paper presents the potential biomechanical challenges affecting the TDR that should be addressed with a hope to improve the clinical outcomes and our understanding of the devices. Appropriate literature and our own research findings comparing the biomechanics of different disc designs are presented to highlight the need for additional investigations. The biomechanical effects of various surgical procedures are analyzed, reiterating the importance of parameters like preserving uncinate processes, disc placement and its orientation within the cervical spine. Moreover, the need for a 360° dynamic system for disc recipients who may experience whiplash injuries is explored. Probabilistic studies as performed already in the lumbar spine may explore high risk combinations of different parameters and explain the differences between "standard" biomechanical investigations and clinical studies. Development of a patient specific optimized finite element model that takes muscle forces into consideration may help resolve the discrepancies between biomechanics of TDR and the clinical studies. Factors affecting long-term performance such as bone remodeling, subsidence, and wear are elaborated. In vivo assessment of segmental spine motion has been, and continues to be, a challenge. In general, clinical studies while reporting the data have placed lesser emphasis on kinematics following intervertebral disc replacements. Evaluation of in vivo kinematics following TDR to analyze the quality and quantity of motion using stereoradiogrammetric technique may be needed.

  13. Evaluation of healthy and sensory indexes of sweetened beverages using an electronic tongue

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Luís G., E-mail: ldias@ipb.pt [CIMO – Escola Superior Agrária, Instituto Politécnico de Bragança, Campus Santa Apolónia, Apartado 1172, 5301-855 Bragança (Portugal); Sequeira, Cédric, E-mail: cedric.b.s@hotmail.com [CIMO – Escola Superior Agrária, Instituto Politécnico de Bragança, Campus Santa Apolónia, Apartado 1172, 5301-855 Bragança (Portugal); Veloso, Ana C.A., E-mail: anaveloso@isec.pt [Instituto Politécnico de Coimbra, ISEC, DEQB, Rua Pedro Nunes, Quinta da Nora, 3030-199 Coimbra (Portugal); CEB – Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Sousa, Mara E.B.C., E-mail: mebsousadias@gmail.com [CIMO – Escola Superior Agrária, Instituto Politécnico de Bragança, Campus Santa Apolónia, Apartado 1172, 5301-855 Bragança (Portugal); Peres, António M., E-mail: peres@ipb.pt [LSRE – Laboratory of Separation and Reaction Engineering – Associate Laboratory LSRE/LCM, Escola Superior Agrária, Instituto Politécnico de Bragança, Campus Santa Apolónia, Apartado 1172, 5301-855 Bragança (Portugal)

    2014-10-27

    Highlights: • Overconsumption of soft-drinks and fruit-beverages may enhance health risks. • Beverage’s healthy and sensory indexes were calculated using chromatographic data. • A potentiometric electronic tongue with multivariate linear models was applied. • E-tongue discriminated samples according to glycemic load or fructose-intolerance levels. • Healthy and sensory indexes were accurately quantified using E-tongue data. - Abstract: Overconsumption of sugar-sweetened beverages may increase the risk of health problems and so, the evaluation of their glycemic load and fructose-intolerance level is essential since it may allow establishing possible relations between physiologic effects of sugar-rich beverages and health. In this work, an electronic tongue was used to accurately classify beverages according to glycemic load (low, medium or high load) as well to their adequacy for people suffering from fructose malabsorption syndrome (tolerable or not): 100% of correct classifications (leave-one-out cross-validation) using linear discriminant models based on potentiomentric signals selected by a meta-heuristic simulated annealing algorithm. These results may be partially explained by the electronic tongue’s capability to mimic the human sweetness perception and total acid flavor of beverages, which can be related with glycemic load and fructose-intolerance index. Finally, the E-tongue was also applied to quantify, accurately, healthy and sensory indexes using multiple linear regression models (leave-one-out cross-validation: R{sub adj} > 0.99) in the following dynamic ranges: 4.7 < glycemic load ≤ 30; 0.4 < fructose intolerance index ≤ 1.5; 32 < sweetness perception < 155; 1.3 < total acid flavor, g L{sup −1} < 8.3; and, 5.8 < well-balanced flavor ≤ 74. So, the proposed electronic tongue could be used as a practical, fast, low-cost and green tool for beverage’s healthy and sensory evaluation.

  14. Case report macroglossia: Review and application of tongue reduction technique

    Directory of Open Access Journals (Sweden)

    Bilommi R. Irhamni

    2015-05-01

    Full Text Available Congenital macroglossia is uncommon condition, Enlargement can be true as seen in vascular malformations or muscular enlargement. It may cause significant symptoms in children such as sleep apnea, respiratory distress, drooling, difficulty in swallowing and dysarthria. Long-standing macroglossia leads to an anterior open bite deformity, mucosal changes, exposure to potential trauma, increased incidence of upper respiratory tract infections and failure to thrive. Tongue movements, sounds and Speech articulation may also be affected. It is important to achieve uniform global reduction of the enlarged tongue for functional as well as esthetic reasons. The multiple techniques advocated for tongue reduction reveal that an ideal procedure has yet to emerge. In our case report we describe a modified reduction technique of the tongue globally preserving the taste, sensation and mobility of the tongue suitable for cases of enlargement of the tongue as in muscular hypertrophy. It can be used for repeat reductions without jeopardizing the mobility and sensibility of the tongue.

  15. Effects of incision and irradiation on regional lymph node metastasis in carcinoma of the hamster tongue

    Energy Technology Data Exchange (ETDEWEB)

    Ohtake, K.; Shingaki, S.; Nakajima, T. (Nigata Univ. (Japan))

    1990-07-01

    The effects of incision and irradiation on regional lymph node metastasis in DMBA-induced squamous cell carcinomas of the hamster tongue are reported. Metastasis to the submandibular lymph nodes was confirmed histologically in 48.0% of the animals. The incidence of lymph node metastasis was significantly increased (65.9%) after repeated incisions of tongue carcinomas. Three gray whole-body irradiation also increased the rate of metastasis from 31.0% to 46.3%. Higher incidences of lymphatic vessel invasion after incision and concomitant lymph node metastasis in the lymphatic invasion-positive group indicated a stepwise relationship leading to an increase in lymph node metastasis after incision. Because of the high incidence of metastases and close resemblance to human carcinomas in the tumor cell deposition and establishment of metastatic foci, DMBA-induced tongue carcinoma with invasion may serve as an experimental model of human oral carcinomas.

  16. Electronic tongue-based discrimination of Korean rice wines (makgeolli) including prediction of sensory evaluation and instrumental measurements.

    Science.gov (United States)

    Kang, Bo-Sik; Lee, Jang-Eun; Park, Hyun-Jin

    2014-05-15

    A commercial electronic tongue was used to discriminate Korean rice wines (makgeolli) brewed from nine cultivars of rice with different amino acid and fatty acid compositions. The E-tongue was applied to establish prediction models with sensory evaluation or LC-MS/MS by partial least squares regression (PLSR). All makgeollis were classified into three groups by principal components analysis, and the separation pattern was affected by rice qualities and yeast fermentation. Makgeolli taste changed from the complicated comprising sweetness, saltiness, and umami to the uncomplicated, such as bitterness and then, sourness, with a decrease of amino acids and fatty acids in the rice. The quantitative correlation between E-tongue and sensory scores or LC-MS/MS by PLSR demonstrated that E-tongue could well predict most of the sensory attributes with relatively acceptable r(2), except for bitterness, but could not predict most of the chemical compounds responsible for taste attributes, except for ribose, lactate, succinate, and tryptophan.

  17. Comparison of multivariate preprocessing techniques as applied to electronic tongue based pattern classification for black tea.

    Science.gov (United States)

    Palit, Mousumi; Tudu, Bipan; Bhattacharyya, Nabarun; Dutta, Ankur; Dutta, Pallab Kumar; Jana, Arun; Bandyopadhyay, Rajib; Chatterjee, Anutosh

    2010-08-18

    In an electronic tongue, preprocessing on raw data precedes pattern analysis and choice of the appropriate preprocessing technique is crucial for the performance of the pattern classifier. While attempting to classify different grades of black tea using a voltammetric electronic tongue, different preprocessing techniques have been explored and a comparison of their performances is presented in this paper. The preprocessing techniques are compared first by a quantitative measurement of separability followed by principle component analysis; and then two different supervised pattern recognition models based on neural networks are used to evaluate the performance of the preprocessing techniques.

  18. Comparison of multivariate preprocessing techniques as applied to electronic tongue based pattern classification for black tea

    Energy Technology Data Exchange (ETDEWEB)

    Palit, Mousumi [Department of Electronics and Telecommunication Engineering, Central Calcutta Polytechnic, Kolkata 700014 (India); Tudu, Bipan, E-mail: bt@iee.jusl.ac.in [Department of Instrumentation and Electronics Engineering, Jadavpur University, Kolkata 700098 (India); Bhattacharyya, Nabarun [Centre for Development of Advanced Computing, Kolkata 700091 (India); Dutta, Ankur; Dutta, Pallab Kumar [Department of Instrumentation and Electronics Engineering, Jadavpur University, Kolkata 700098 (India); Jana, Arun [Centre for Development of Advanced Computing, Kolkata 700091 (India); Bandyopadhyay, Rajib [Department of Instrumentation and Electronics Engineering, Jadavpur University, Kolkata 700098 (India); Chatterjee, Anutosh [Department of Electronics and Communication Engineering, Heritage Institute of Technology, Kolkata 700107 (India)

    2010-08-18

    In an electronic tongue, preprocessing on raw data precedes pattern analysis and choice of the appropriate preprocessing technique is crucial for the performance of the pattern classifier. While attempting to classify different grades of black tea using a voltammetric electronic tongue, different preprocessing techniques have been explored and a comparison of their performances is presented in this paper. The preprocessing techniques are compared first by a quantitative measurement of separability followed by principle component analysis; and then two different supervised pattern recognition models based on neural networks are used to evaluate the performance of the preprocessing techniques.

  19. Contribution of biomechanics to clinical practice in orthopaedics.

    Science.gov (United States)

    Woo, Savio L-Y

    2004-01-01

    Biomechanics is a field that has a very long history. It was described in ancient Chinese and Greek literature as early as 400-500 BC. The foundation of biomechanics, however, was laid during a period between the 1500's to 1700's by renowned personalities, da Vinci, Galileo, Borelli, Hooke, Newton, and so (Fung, Y.C., Biomechanics: Mechanical Properties of Living Tissues, 2nd Ed. Springer Verlag, Chapter 1, 1993). Beginning in the 1950's, Muybridge, Steindler, Inman, Lissner, and Hirsch performed the pioneering work on musculoskeletal biomechanics and the foundation of orthopaedic biomechanics was formed. For the following two decades, the field has blossomed and significant contributions in the biomechanics of bone, articular cartilage, soft tissues, upper and lower extremities, spine and so on has been made. More sophisticated equipment, coupled with mathematical modeling and better engineering design, has enabled us to make great strides. Bioengineers, in collaboration with orthopaedic surgeons, have translated many laboratory discoveries into clinical practice, leading to improved patient treatment and outcome. In the past 30 years, my colleagues and I have focused our research on the biomechanics of musculoskeletal soft tissues, ligaments and tendons, in particular. Therefore, in this lecture, the function of knee ligaments, the associated homeostatic responses secondary to immobilization and exercise, and healing of the ligaments will be reviewed. Examples of scientific findings that help to guide the surgical management of injury to ligaments will be given. New ideas on functional tissue engineering to improve the healing of knee ligaments and tendons will be presented. We have learned that tendons and ligaments are indeed complex biological tissues. To fully understand their behavior, healing and remodelling processes, this author advocates major efforts be made to bring molecular biologists, morphologists, biochemists, bioengineers, physical therapists and

  20. 中医屈指推法的生物力学建模及分析%Biomechanical model preparation and analysis of pushing manipulation with one-finger meditation (thumb flexion)

    Institute of Scientific and Technical Information of China (English)

    吕杰; 曹金凤; 方磊; 方舟; 章丹颂; 马龙龙; 许世雄; 房敏

    2011-01-01

    BACKGROUND: The development trend of Chinese massage is to get rid of the experience-oriented mode and gradually gets objective, accurate, quantitative and individual. Therefore, the quantitative research of massage is emergently needed.OBJECTIVE: To build a biomechanical model of pushing manipulation with one-finger meditation (thumb flexion) and put forward a method to calculate the force of joints which can hardly be measured noninvasively in vivo.METHODS: Cameras and Chinese massage force analyzer (FZ-I) were used to collect kinematic data and force data, and then a biomechanical model was established to calculate the force of joints according to these data.RESULTS AND CONCLUSION: A biomechanical model of pushing manipulation with one-finger meditation (thumb flexion) with 4 bars and 5 nodes was established, the force of thumb joint, thumb metacarpophalangeal joint, wrist joint and elbow joint was calculated and the function of the joints in manipulation was analyzed. The results were consistent with manipulator's feeling. The force of joints in pushing manipulation with one-finger meditation (thumb flexion) can be calculated through the biomechanical model. The method may be useful for massage teaching and researching.%背景:推拿医学发展趋势是逐步摆脱单纯经验化的模式,走向客观化、精确化、量化和个体化,使推拿医师能控制手法的力量、时间、方向、频率等各项指标.目的:建立中医一指禅推法(屈指)的生物力学模型,探索在体情况下无0法无创检测的关节作用力的计算方法.方法:采用摄像技术,采集一指禅推法(屈指)的运动学数据,同时利用FZ-I型中医推拿手法测力分析仪采集作用力数据,依此建立手法的生物力学模型并计算各主要关节的作用力.结果与结论:建立了4杆件、5结点的中医一指禅推法(屈指)生物力学模型,计算得到了拇指指间关节、拇指掌指关节、腕关节

  1. The Biomechanics of Cervical Spondylosis

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    Lisa A. Ferrara

    2012-01-01

    Full Text Available Aging is the major risk factor that contributes to the onset of cervical spondylosis. Several acute and chronic symptoms can occur that start with neck pain and may progress into cervical radiculopathy. Eventually, the degenerative cascade causes desiccation of the intervertebral disc resulting in height loss along the ventral margin of the cervical spine. This causes ventral angulation and eventual loss of lordosis, with compression of the neural and vascular structures. The altered posture of the cervical spine will progress into kyphosis and continue if the load balance and lordosis is not restored. The content of this paper will address the physiological and biomechanical pathways leading to cervical spondylosis and the biomechanical principles related to the surgical correction and treatment of kyphotic progression.

  2. The biomechanics of cervical spondylosis.

    Science.gov (United States)

    Ferrara, Lisa A

    2012-01-01

    Aging is the major risk factor that contributes to the onset of cervical spondylosis. Several acute and chronic symptoms can occur that start with neck pain and may progress into cervical radiculopathy. Eventually, the degenerative cascade causes desiccation of the intervertebral disc resulting in height loss along the ventral margin of the cervical spine. This causes ventral angulation and eventual loss of lordosis, with compression of the neural and vascular structures. The altered posture of the cervical spine will progress into kyphosis and continue if the load balance and lordosis is not restored. The content of this paper will address the physiological and biomechanical pathways leading to cervical spondylosis and the biomechanical principles related to the surgical correction and treatment of kyphotic progression.

  3. Biomechanics of Gait during Pregnancy

    OpenAIRE

    2014-01-01

    Introduction. During pregnancy women experience several changes in the body’s physiology, morphology, and hormonal system. These changes may affect the balance and body stability and can cause discomfort and pain. The adaptations of the musculoskeletal system due to morphological changes during pregnancy are not fully understood. Few studies clarify the biomechanical changes of gait that occur during pregnancy and in postpartum period. Purposes. The purpose of this re...

  4. Study on classification of soy sauce by electronic tongue technique combined with artificial neural network.

    Science.gov (United States)

    Ou-Yang, Qin; Zhao, Jie-Wen; Chen, Quan-Sheng; Lin, Hao; Huang, Xing-Yi

    2011-01-01

    Electronic tongue as an analytical tool coupled with pattern recognition was attempted to classify 4 different brands and 2 categories (produced by different processes) of Chinese soy sauce. An electronic tongue system was used for data acquisition of the samples. Some effective variables were extracted from electronic tongue data by principal component analysis (PCA). Backpropagation artificial neural network (BP-ANN) was applied to build identification models. PCA score plots show an obvious cluster trend of different brands and different categories of soy sauce in the 2-dimensional space. The optimal BP-ANN model for different brands was achieved when principal components (PCs) were 2, and the identification rate of the discrimination model was 100% in both the calibration set and the prediction set, and the optimal BP-ANN model for different categories had the same result. This work demonstrates that electronic tongue technology combined with a suitable pattern recognition method can be successfully used in the classification of different brands and categories of soy sauce.

  5. Biomechanics of Pediatric Manual Wheelchair Mobility

    OpenAIRE

    2015-01-01

    Currently, there is limited research of the biomechanics of pediatric manual wheelchair mobility. Specifically, the biomechanics of functional tasks and their relationship to joint pain and health is not well understood. To contribute to this knowledge gap, a quantitative rehabilitation approach was applied for characterizing upper extremity biomechanics of manual wheelchair mobility in children and adolescents during propulsion, starting and stopping tasks. A Vicon motion analysis system ...

  6. Sport and Exercise Biomechanics (Bios Instant Notes)

    OpenAIRE

    Paul Grimshaw; Adrian Lees; Neil Fowler; Adrian Burden

    2007-01-01

    DESCRIPTION Instant Notes on Sport and Exercise Biomechanics provides a broad overview of the fundamental concepts in exercise and sport biomechanics. PURPOSE The book aims to provide instant notes on essential information about biomechanics, and is designed to help undergraduate students to grasp the corresponding subjects in physical effort rapidly and easily. AUDIENCE The book provides a useful resource for undergraduate and graduate students as a fundamental reference book. For the resear...

  7. [Observation of the ultrastructure of the tongue coating].

    Science.gov (United States)

    Watanabe, Hideaki

    2006-03-01

    An observational study was conducted to clarify the morphological features of the fine structure of the tongue coating, which is one of the main causes of halitosis. Tongue specimens from cadavers, whom dental students had practiced on for anatomy class, were used as materials to observe the surface structure. Tongue coatings were obtained from patients who were referred to the Fresh Breath Clinic, Dental Hospital, Tokyo Medical and Dental University. After macroscopic observation of the tongue surface, tongue coating and examination of halitosis, the tongue coating was scraped carefully, following which it was observed using a light microscope and transmission electron microscope (TEM). The results obtained were as follows. The tongue coating consisted mainly of bacteria and desquamated keratinized epithelium which originated chiefly from the filiform papilla. The desquamated keratinized epithelium was also composed of degenerated epithelium of every level, from a comparatively normal epithelium to a fragmented altered epithelium. In addition, the level of degeneration of the keratinized epithelium differed according to the state of distribution and the revitalization of bacteria located in its surroundings. The intensity of halitosis increased with the amount of tongue coating. Increased amounts of tongue coating, however, did not necessarily correlate with increased halitosis in the patients. It was suggested that the severity of halitosis was probably associated with the level of bacterial invasion-related degeneration of the desquamated keratinized epithelium (tongue coating's quality).

  8. Proposal for a New Noncontact Method for Measuring Tongue Moisture to Assist in Tongue Diagnosis and Development of the Tongue Image Analyzing System, Which Can Separately Record the Gloss Components of the Tongue

    Directory of Open Access Journals (Sweden)

    Toshiya Nakaguchi

    2015-01-01

    Full Text Available Tongue diagnosis is a noninvasive diagnosis and is traditionally one of the most important tools for physicians who practice Kampo (traditional Japanese medicine. However, it is a subjective process, and its results can depend on the experience of the physician performing it. Previous studies have reported how to measure and evaluate the shape and color of the tongue objectively. Therefore, this study focused on the glossy component in order to quantify tongue moisture in tongue diagnosis. We hypothesized that moisture appears as a gloss in captured images and measured the amount of water on the tongue surface in 13 subjects. The results showed a high correlation between the degree of gloss and the amount of water on the tongue surface and suggested that the moisture on the tongue can be estimated by the degree of gloss in a captured image. Because the moisture level on the tongue changes during the course of taking photos, it became clear that we had to wait at least 3 minutes between photos. Based on these results, we established the tongue image analyzing system (TIAS, which can consistently record the gloss and color of the tongue surface simultaneously.

  9. Biomechanical stability of a bioabsorbable self-retaining polylactic acid/nano-sized β-tricalcium phosphate cervical spine interbody fusion device in single-level anterior cervical discectomy and fusion sheep models

    Directory of Open Access Journals (Sweden)

    Cao L

    2012-11-01

    Full Text Available Lu Cao,1 Ping-Guo Duan,1 Xi-Lei Li,1 Feng-Lai Yuan,3 Ming-Dong Zhao,2 Wu Che,1 Hui-Ren Wang,1 Jian Dong11Department of Orthopedic Surgery, Zhongshan Hospital, State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai, China; 2Department of Orthopedic Surgery, Jinshan Hospital, Fudan University, Shanghai, China; 3Affiliated Third Hospital of Nantong University, Wuxi, ChinaPurpose: The aim of this study was to investigate the biomechanical stability provided by a novel, polylactic acid/nano-sized, β-tricalcium phosphate, bioabsorbable, self-retaining cervical fusion cage (BCFC.Methods: Quasistatic nonconstraining torques (maximum 1.5 NM induced flexion, extension, lateral bending (±1.5 NM, and axial rotation (±1.5 NM on 32 sheep cervical spines (C2–C5. The motion segment C3–C4 was first tested intact; the following groups were tested after complete discectomy: autologous tricortical iliac crest bone graft, Medtronic–Wego polyetheretherketone (PEEK cage, Solis PEEK cage, and BCFC. The autologous bone graft group was tested with an anterior plate. The mean range of motion (ROM was calculated from the load-displacement curves.Results: BCFC significantly decreased ROM in lateral bending and axial rotation compared to other implants, and no significant difference in ROM between two types of PEEK cages and BCFC could be observed in flexion and extension. Anterior cervical plate (ACP significantly decreased ROM in flexion and extension, but no significant difference in ROM between BCFC and bone graft plus ACP could be determined in lateral bending and axial rotation.Conclusion: The BCFC device showed better stability to autologous tricortical iliac crest bone graft and PEEK cages in single-level anterior cervical discectomy and fusion models and thus may be a potential alternative to the current PEEK cages.Keywords: biomechanics, cervical spine, cages, bioabsorbable, sheep

  10. Harmonic scalpel versus flexible CO2 laser for tongue resection: A histopathological analysis of thermal damage in human cadavers

    Directory of Open Access Journals (Sweden)

    Wolf Tamir

    2011-08-01

    Full Text Available Abstract Background Monopolar cautery is the most commonly used surgical cutting and hemostatic tool for head and neck surgery. There are newer technologies that are being utilized with the goal of precise cutting, decreasing blood loss, reducing thermal damage, and allowing faster wound healing. Our study compares thermal damage caused by Harmonic scalpel and CO2 laser to cadaveric tongue. Methods Two fresh human cadaver heads were enrolled for the study. Oral tongue was exposed and incisions were made in the tongue akin to a tongue tumor resection using the harmonic scalpel and flexible C02 laser fiber at various settings recommended for surgery. The margins of resection were sampled, labeled, and sent for pathological analysis to assess depth of thermal damage calculated in millimeters. The pathologist was blinded to the surgical tool used. Control tongue tissue was also sent for comparison as a baseline for comparison. Results Three tongue samples were studied to assess depth of thermal damage by harmonic scalpel. The mean depth of thermal damage was 0.69 (range, 0.51 - 0.82. Five tongue samples were studied to assess depth of thermal damage by CO2 laser. The mean depth of thermal damage was 0.3 (range, 0.22 to 0.43. As expected, control samples showed 0 mm of thermal damage. There was a statistically significant difference between the depth of thermal injury to tongue resection margins by harmonic scalpel as compared to CO2 laser, (p = 0.003. Conclusion In a cadaveric model, flexible CO2 laser fiber causes less depth of thermal damage when compared with harmonic scalpel at settings utilized in our study. However, the relevance of this information in terms of wound healing, hemostasis, safety, cost-effectiveness, and surgical outcomes needs to be further studied in clinical settings.

  11. Electronic Noses and Tongues in Wine Industry

    Directory of Open Access Journals (Sweden)

    Maria Luz Rodriguez-Mendez

    2016-10-01

    Full Text Available The quality of wines is usually evaluated by a sensory panel formed of trained experts or traditional chemical analysis. Over the last few decades, electronic noses and electronic tongues have been developed to determine the quality of foods and beverages. They consist of arrays of sensors with cross-sensitivity, combined with pattern recognition software, which provide a fingerprint of the samples that can be used to discriminate or classify the samples. This holistic approach is inspired by the method used in mammals to recognize food through their senses. They have been widely applied to the analysis of wines, including quality control, aging control or the detection of fraudulence, among others. In this paper, the current status of research and development in the field of electronic noses and tongues applied to the analysis of wines is reviewed. Their potential applications in the wine industry are described. The review ends with a final comment about expected future developments.

  12. Biomolecular Markers in Cancer of the Tongue

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    Daris Ferrari

    2009-01-01

    Full Text Available The incidence of tongue cancer is increasing worldwide, and its aggressiveness remains high regardless of treatment. Genetic changes and the expression of abnormal proteins have been frequently reported in the case of head and neck cancers, but the little information that has been published concerning tongue tumours is often contradictory. This review will concentrate on the immunohistochemical expression of biomolecular markers and their relationships with clinical behaviour and prognosis. Most of these proteins are associated with nodal stage, tumour progression and metastases, but there is still controversy concerning their impact on disease-free and overall survival, and treatment response. More extensive clinical studies are needed to identify the patterns of molecular alterations and the most reliable predictors in order to develop tailored anti-tumour strategies based on the targeting of hypoxia markers, vascular and lymphangiogenic factors, epidermal growth factor receptors, intracytoplasmatic signalling and apoptosis.

  13. Carcinoma cuniculatum arising in the tongue.

    Science.gov (United States)

    Thavaraj, Selvam; Cobb, Alistair; Kalavrezos, Nicholas; Beale, Timothy; Walker, Donald Murray; Jay, Amrita

    2012-03-01

    Carcinoma cuniculatum (CC) is a rare, distinct clinico-pathological variant of squamous cell carcinoma (SCC) that is defined histologically by the characteristic infiltrative pattern of a deep, broad, and complex proliferation of stratified squamous epithelium with keratin cores and keratin-filled crypts. Herein, we present a case report of CC of the oral tongue and discuss its diagnosis, management, and outcome, as well as briefly review the world literature. To our knowledge, this is the first documented case of CC of the tongue to be reported in the English literature. We draw attention to its clinico-pathological features and highlight that awareness of this entity as a distinct variant of SCC facilitates its correct management.

  14. Flow and mixing around a glacier tongue

    Directory of Open Access Journals (Sweden)

    C. L. Stevens

    2010-08-01

    Full Text Available A glacier tongue floating in the coastal ocean presents a significant obstacle to the local flow and influences oceanic mixing and transport processes. Here ocean shear microstructure observations at a glacier tongue side-wall show tidally-induced flow pulses and vortices as well as concomitant mixing. Flow speeds within the pulses reached around three times that of the ambient tidal flow amplitude and generated vertical velocity shear as large as 3×10−3 s−1. During the maximum flow period turbulent energy dissipation rates reached a maximum of 10−5 m2 s−3, around three decades greater than local background levels. This is in keeping with estimates of the gradient Richardson Number which dropped to around unity. Associated vertical diffusivities are higher that expected from parameterization, possibly reflecting the proximity of the cryotopography.

  15. Bmi1-positive cells in the lingual epithelium could serve as cancer stem cells in tongue cancer.

    Science.gov (United States)

    Tanaka, Toshihiro; Atsumi, Naho; Nakamura, Naohiro; Yanai, Hirotsugu; Komai, Yoshihiro; Omachi, Taichi; Tanaka, Kiyomichi; Ishigaki, Kazuhiko; Saiga, Kazuho; Ohsugi, Haruyuki; Tokuyama, Yoko; Imahashi, Yuki; Hisha, Hiroko; Yoshida, Naoko; Kumano, Keiki; Okazaki, Kazuichi; Ueno, Hiroo

    2016-12-22

    We recently reported that the polycomb complex protein Bmi1 is a marker for lingual epithelial stem cells (LESCs), which are involved in the long-term maintenance of lingual epithelial tissue in the physiological state. However, the precise role of LESCs in generating tongue tumors and Bmi1-positive cell lineage dynamics in tongue cancers are unclear. Here, using a mouse model of chemically (4-nitroquinoline-1-oxide: 4-NQO) induced tongue cancer and the multicolor lineage tracing method, we found that each unit of the tumor was generated by a single cell and that the assembly of such cells formed a polyclonal tumor. Although many Bmi1-positive cells within the tongue cancer specimens failed to proliferate, some proliferated continuously and supplied tumor cells to the surrounding area. This process eventually led to the formation of areas derived from single cells after 1-3 months, as determined using the multicolor lineage tracing method, indicating that such cells could serve as cancer stem cells. These results indicate that LESCs could serve as the origin for tongue cancer and that cancer stem cells are present in tongue tumors.

  16. The association of tongue posture with the dentoalveolar maxillary and mandibular morphology in Class III malocclusion: a controlled study.

    Science.gov (United States)

    Primozic, Jasmina; Farcnik, Franc; Perinetti, Giuseppe; Richmond, Stephen; Ovsenik, Maja

    2013-06-01

    The aim of the present study was to evaluate the association of tongue posture with the dentoalveolar maxillary and mandibular morphology in a group of Class III subjects in comparison to a group of Class I subjects. Twenty Class III subjects (9 males, 11 females, 19.2 ± 4.6 years) and 20 Class I subjects (6 males, 14 females, 17.4 ± 1.7 years) were included in the present study. Maxillary and mandibular morphology was defined by the intermolar and intercanine distances, at both the cusps and gingival levels, and by measuring surface area and volume of the palatal vault and mouth floor assessed on three-dimensional digital models. Tongue-to-palate distances were measured on lateral cephalograms. The groups were compared using the Mann-Whitney U-test and correlations between each morphological parameter and the tongue-to-palate distances were calculated using the Spearman correlation coefficient. The mandibular intermolar width at the gingival level was significantly greater in the Class III group (P Class III group (P Class III group (P = 0.01). The tongue-to-palate distances were generally greater, i.e. lower tongue posture, for the Class III subjects. Significant correlations were seen between tongue-to-palate distances in the posterior region with the area ratio (rho = 0.44, P Class III subjects and is associated with the dentoalveolar characteristics of the maxilla and mandible.

  17. Pathobiology of obesity and osteoarthritis: integrating biomechanics and inflammation

    Directory of Open Access Journals (Sweden)

    Rita I. Issa

    2012-05-01

    Full Text Available Obesity is a significant risk factor for developing osteoarthritis in weight-bearing and non-weight-bearing joints. Although the pathogenesis of obesity-associated osteoarthritis is not completely understood, recent studies indicate that pro-inflammatory metabolic factors contribute to an increase in osteoarthritis risk. Adipose tissue, and in particular infrapatellar fat, is a local source of pro-inflammatory mediators that are increased with obesity and have been shown to increase cartilage degradation in cell and tissue culture models. One adipokine in particular, leptin, may be a critical mediator of obesity-associated osteoarthritis via synergistic actions with other inflammatory cytokines. Biomechanical factors may also increase the risk of osteoarthritis by activating cellular inflammation and promoting oxidative stress. However, some types of biomechanical stimulation, such as physiologic cyclic loading, inhibit inflammation and protect against cartilage degradation. A high percentage of obese individuals with knee osteoarthritis are sedentary, suggesting that a lack of physical activity may increase the susceptibility to inflammation. A more comprehensive approach to understanding how obesity alters daily biomechanical exposures within joint tissues may provide new insight into the protective and damaging effects of biomechanical factors on inflammation in osteoarthritis.

  18. Changing step width alters lower extremity biomechanics during running.

    Science.gov (United States)

    Brindle, Richard A; Milner, Clare E; Zhang, Songning; Fitzhugh, Eugene C

    2014-01-01

    Step width is a spatiotemporal parameter that may influence lower extremity biomechanics at the hip and knee joint. The purpose of this study was to determine the biomechanical response of the lower extremity joints to step width changes during running. Lower extremity data from 30 healthy runners, half of them male, were collected during running in three step width conditions: preferred, wide, and narrow. Dependent variables and step width were analyzed using a mixed model ANOVA and pairwise t-tests for post hoc comparisons. Step width was successfully altered in the wide and narrow conditions. Generally, frontal plane peak values decreased as step width increased from narrow to preferred to wide. Peak hip adduction and rearfoot eversion angles decreased as step width increased from narrow to wide. Peak knee abduction moment and knee abduction impulse also decreased as step width increased from narrow to wide. Although men and women ran differently, gender only influenced the effect of step width on peak rearfoot inversion moment. In conclusion, step width influences lower extremity biomechanics in healthy runners. When step width increased from narrow to wide, peak values of frontal plane variables decreased. In addition to previously reported changes at the rearfoot, the hip and knee joint biomechanics were also influenced by changes in step width.

  19. How to Assess the Biomechanical Risk Levels in Beekeeping.

    Science.gov (United States)

    Maina, G; Rossi, F; Baracco, A

    2016-01-01

    Beekeepers are at particular risk of developing work-related musculoskeletal disorders, but many of the studies lack detailed exposure assessment. To evaluate the biomechanical overload exposure in a specific farming activity, a multitasking model has been developed through the characterization of 37 basic operational tasks typical of the beekeeping activity. The Occupational Repetitive Actions (OCRA) Checklist and the National Institute for Occupational Safety and Health (NIOSH) Lifting Index methodologies have been applied to these elementary tasks to evaluate the exposure, and the resulting risk indices have been time-weighted averaged. Finally, an easy access, computer-assisted toolkit has been developed to help the beekeepers in the biomechanical risk assessment process. The risk of biomechanical overload for the upper limbs ranges from acceptable (maintenance and recovery of woody material and honey packaging with dosing machine tasks) to high (distribution of the top supers) risk level. The risk for back injury is always borderline in women and increases with exposure time, whereas it ranges from acceptable to borderline in men. The definition of the biomechanical risk levels allows for planning of corrective actions aimed at preventing and reducing the risk of musculoskeletal disorders through engineering, administrative, and behavioral interventions. The methodology can be used for risk assessment in other mainly manual agricultural activities.

  20. LUMBAR SPINAL STENOSIS. A REVIEW OF BIOMECHANICAL STUDIES

    Institute of Scientific and Technical Information of China (English)

    戴力扬; 徐印坎

    1998-01-01

    ObjectS. To investigate the biomechanical aspects of etiology, pathology, clinical manifestation, diagnosis and surgical treatment of the lumbar spinal stenosis. Methods. A series of biomechanical methods, such as three-dimensional finite element models, threedimensional kinematic measurement, cadeveric evaluation, and imaging assessment was applied to correlate lumbar biomechanics and lumber spinal stenosls. Surgery of lumber spinal stenosis has been improved. Results.The stresses significantly concentrate on the posterolateral part of the annulus fibrcsms of disc, the posterior surface of vertebral body, the pedlcle, the interarticularis and the beet joints. This trend is intensified by disc degeneration and lumber backward extension. Posterior elcxnent resection has a definite effect upon the biomechanical behavior of lumbar vertebrae. The improved operations proved satisfactory. Conclusion. Stress concentration in the lumber vertebrae is of importance to the etiology of degenerative lumbar spinal stenosls, and disc degeneratkm is the initial key of this process. Than these will be aggravatnd by backward extension. Functloval radiography and myelography are of assistance to the diagnosis of the lumhar spinal stenosls. For the surgcal treatment of the lumber spinal stenosis, destruction of the posterior element should be avoid as far as possible based upon the thorough decmnpression. Maintaining the lumbar spine in flexion by fusion after decorapression has been proved a useftd method. When developmental spinal stenoals is combined with disc herniation, discectoray through laminotomy is recommend for decompression.

  1. Targeted delivery of lovastatin and tocotrienol to fracture site promotes fracture healing in osteoporosis model: micro-computed tomography and biomechanical evaluation.

    Directory of Open Access Journals (Sweden)

    Nurul 'Izzah Ibrahim

    Full Text Available Osteoporosis is becoming a major health problem that is associated with increased fracture risk. Previous studies have shown that osteoporosis could delay fracture healing. Although there are potential agents available to promote fracture healing of osteoporotic bone such as statins and tocotrienol, studies on direct delivery of these agents to the fracture site are limited. This study was designed to investigate the effects of two potential agents, lovastatin and tocotrienol using targeted drug delivery system on fracture healing of postmenopausal osteoporosis rats. The fracture healing was evaluated using micro CT and biomechanical parameters. Forty-eight Sprague-Dawley female rats were divided into 6 groups. The first group was sham-operated (SO, while the others were ovariectomized (OVx. After two months, the right tibiae of all rats were fractured at metaphysis region using pulsed ultrasound and were fixed with plates and screws. The SO and OVxC groups were given two single injections of lovastatin and tocotrienol carriers. The estrogen group (OVx+EST was given daily oral gavages of Premarin (64.5 µg/kg. The Lovastatin treatment group (OVx+Lov was given a single injection of 750 µg/kg lovastatin particles. The tocotrienol group (OVx+TT was given a single injection of 60 mg/kg tocotrienol particles. The combination treatment group (OVx+Lov+TT was given two single injections of 750 µg/kg lovastatin particles and 60 mg/kg tocotrienol particles. After 4 weeks of treatment, the fractured tibiae were dissected out for micro-CT and biomechanical assessments. The combined treatment group (OVx+Lov+TT showed significantly higher callus volume and callus strength than the OVxC group (p<0.05. Both the OVx+Lov and OVx+TT groups showed significantly higher callus strength than the OVxC group (p<0.05, but not for callus volume. In conclusion, combined lovastatin and tocotrienol may promote better fracture healing of osteoporotic bone.

  2. Tongue Liminary Threshold Identification to Electrotactile Stimulation

    CERN Document Server

    Robineau, Fabien; Orliaguet, Jean-Pierre; Payan, Yohan

    2007-01-01

    Many applications use electrostimulation of the human skin to provide tactile sensation. The effect of electrotactile stimulations were studied on a 6x6 matrix of tactile electrodes placed on the anterior part of the tongue. The liminary threshold with continuous or discontinuous waveform and patterns with 2 or 4 electrodes was investigated. The result suggest that for energy saving and to improve the yield, it would probably be better to use discontinuous stimulation with two electrode patterns.

  3. Actinomycosis of The Tongue: A Diagnostic Dilemma

    Directory of Open Access Journals (Sweden)

    Aniece Chowdary, Anirudh Kaul, Surinder Atri*

    2010-10-01

    Full Text Available Actinomycosis is a bacterial, suppurative chronic infectious disease caused by Actinomyces israelli.Actinomycotic infections of the cervicofacial region are not uncommon , however Actinomycosis of tongueis rare. A mass that may mimic both benign and malignant neoplasms can be seen at clinical presentationand may mislead the diagnosis. We report a patient who presented with a tumor like tongue mass causingspeech disturbance and difficulty in swallowing, diagnosed as actinomycosis

  4. Cysticercosis of tongue: Cytohistologic approach to diagnosis

    Directory of Open Access Journals (Sweden)

    Govindaswamy Koteeswaran

    2013-01-01

    Full Text Available Cysticercosis is continuing to be a major health problem in developing countries. Radiological and serological techniques are routinely used for pre-operative diagnosis of cysticercosis. But fine needle aspiration cytology (FNAC is cost effective and simple procedure, so it is important to be aware of diagnostic pitfalls in the cytomorphologic diagnosis of cysticercosis. We present a case of cysticercosis of tongue, which accounts for only 34 cases in the world literature.

  5. Characterization and Modeling of Thoraco-Abdominal Response to Blast Waves. Volume 4. Biomechanical Model of Thorax Response to Blast Loading

    Science.gov (United States)

    1985-05-01

    SUB-GROUP06 217• 06 2 19, ABSTRACT (Conltiwe on rever Ni nftwy wf’, mbbr )y p 20. DISTRIIUTION IAVAILABILITY OF ABSTRACT 21. AOSTRACT SECURITY...35 4.1.1 Treatments of Lumped Material Properties on the FEN Model ................................ .s......s....... 35 4.1.2 Material...points of those elements describing the internal organs. This treatment brings the contributions of rib cage and muscle layer Into consideration. It

  6. Effectiveness of a new toothbrush design versus a conventional tongue scraper in improving breath odor and reducing tongue microbiota

    Directory of Open Access Journals (Sweden)

    Luciana Assirati Casemiro

    2008-08-01

    Full Text Available For centuries, specific instruments or regular toothbrushes have routinely been used to remove tongue biofilm and improve breath odor. Toothbrushes with a tongue scraper on the back of their head have recently been introduced to the market. The present study compared the effectiveness of a manual toothbrush with this new design, i.e., possessing a tongue scraper, and a commercial tongue scraper in improving breath odor and reducing the aerobic and anaerobic microbiota of tongue surface. The evaluations occurred at 4 moments, when the participants (n=30 had their halitosis quantified with a halimeter and scored according to a 4-point scoring system corresponding to different levels of intensity. Saliva was collected for counts of aerobic and anaerobic microorganisms. Data were analyzed statistically by Friedman's test (p<0.05. When differences were detected, the Wilcoxon test adjusted for Bonferroni correction was used for multiple comparisons (group to group. The results confirmed the importance of mechanical cleaning of the tongue, since this procedure provided an improvement in halitosis and reduction of aerobe and anaerobe counts. Regarding the evaluated methods, the toothbrush's tongue scraper and conventional tongue scraper had a similar performance in terms of breath improvement and reduction of tongue microbiota, and may be indicated as effective methods for tongue cleaning.

  7. Tissue kinetics in mouse tongue mucosa during daily fractionated radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Doerr, W. [Universitaetsklinikum Carl Gustav Carus, Dresden (Germany). Klinik und Poliklinik fuer Strahlentherapie]|[Institut fuer Strahlenbiologie, Oberschleissheim (Germany); Emmendoerfer, H.; Weber-Frisch, M. [Institut fuer Strahlenbiologie, Oberschleissheim (Germany)

    1996-09-01

    The purpose of the present investigation was to quantify cell flux between the distinct layers of the epithelial lining of the ventral surface of mouse tongue during daily fractionated radiotherapy. In tongue epithelium of untreated mice, the minimum residence time of cells in the germinal layer is 2-3 days. Migration through the functional layers requires an additional 2-3 days before labelled cells are observed in the most superficial layer of nucleated cells. A plateau in LI is observed for several days post-labelling in control epithelium, indicating an equilibrium between loss and proliferation of labelled cells. During fractionated radiotherapy, the minimum time from division to occurrence of labelled cells in the stratum lucidum is less than 2 days, and hence significantly shorter than in control epithelium. In contrast to untreated epithelium, no plateau in the germinal layer LI is seen, indicating that frequently both labelled daughters from dividing labelled cells are being lost from this compartment. In conclusion, the present data support a recently described model of radiation-induced accelerated repopulation in squamous epithelia, which postulates that the majority of damaged cells undergoes abortive divisions resulting in two differentiating daughters. (Author).

  8. Base of Tongue Tuberculosis: A Case Report

    Directory of Open Access Journals (Sweden)

    Carlos Chiesa Estomba

    2015-05-01

    Full Text Available Introduction: Tuberculosis is an infectious disease that has displayed increasing incidence in the last decades. It is estimated that up to 20% of tuberculosis cases affect extra-pulmonary organs. In the ENT area, soft palate and tongue are the least probable locations.   Case Report A 62-year-old female with a history of rheumatoid arthritis and treatment with corticosteroids and Adalimumab, developed a foreign body sensation in the pharynx accompanied by a sore throat and halitosis. The laryngoscopy with a 70 degree rigid telescope showed an ulcerated hypertrophic lesion in the right vallecula of about 2-3 cm in the base of the tongue. Acid-alcohol resistant bacilli were found positive for M. tuberculosis, through the Ziehl Neelsen method and Löwenstein culture the patient was treated with tuberculostatic medication. Conclusion:  TB is a possible diagnosis when in the presence of an ulcerated lesion at the base of the tongue, accompanied by sore throat, dysphagia, or foreign body sensation.

  9. Methods and studies of tongue reconstruction

    Institute of Scientific and Technical Information of China (English)

    Fahmi A. Numan; LIAO Gui-qing

    2007-01-01

    Total and even partial glossectomy could be a major event in the life of a patient. Tongue function is so complicated which makes maintaining normal functions of the tongue such as swallowing and speech and preserving larynx integrity after the surgery is a primary objective of the surgeon. This task is very difficult and the result is not predictable. Recent years, however, there has been interesting developments in microsurgical techniques, and these advancements enable oral and maxillofacial surgeons to achieve better results and improve the quality of their patient's life. The results even with use of the new technology are still far from perfect. Several reasons may cause variation in the result. Some of them have to do with the patient such as general health and other reasons are due to the method that is used and nature of the defect after the removal of the tumor. This article was undertaken to summarize the various methods and techniques used over the years to restore oral tongue functions after defects.

  10. DIFFERENTIAL DIAGNOSIS OF LONG TERM TONGUE ULCERS

    Directory of Open Access Journals (Sweden)

    Hegde Nidarsh D.

    2012-08-01

    Full Text Available Oral ulcers is a very common disorder of the oral mucosa. Patients with signs or symptoms of oral ulcers are sometimes referred to gastroenterology clinics, however, in most instances the ulcers does not reflect gastrointestinal disease, some with a chronic non- healing ulcer are advised biopsy. Indeed, a spectrum of disorders can give rise to oral mucosal ulcers ranging from minor local trauma to significant local disease such as malignancy or systemic illness. Lesions of the tongue have a broad differential diagnosis ranging from benign idiopathic processes to infections, cancers, and infiltrative disorders. This article will focus on common ulcerative disorders of the tongue in aspects of their clinical features and differential diagnosis, two case reports with the diagnosis and conservative management for long-term chronic ulcers. The two cases which are reported in this article had a differential diagnosis of Squamous cell carcinoma of the tongue. The clinical picture was craterlike lesion, having a velvety-red base and a rolled, indurated border and most important painless in both cases. Removal of the irritant which was the tooth, rehabilitation of the oral mucosa by lubrication with Cocus Nucifera resulted in the healing of the ulcers. Functional components of Cocus Nucifera are Squaline, tocopherol, phytosterols and other sterols which are all plant steroids.

  11. TONGUE BASE SCHWANNOMA : A RARE ENTITY

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    Vivek

    2015-03-01

    Full Text Available INTRODUCTION: Schwannomas are the benign tumours arising from the Schwann cells. Intraoral and pharyngeal schwannomas are rare and constitute less than 1%. CASE REPORT: We report a case of a 39 year old lady who presented with progressive dysphagia and dysphonia since three months. Intraoral examination showed a well - defined reddish lesion arising from the base of the tongue. She was referred to the department of radiodiagnosis for CT and MRI of the neck to know the extent of the lesion. Differential diagnosis of schwannoma and minor salivary gland tumor was given. Excision biopsy of the lesion was done and the histologic examination showed it as schwannoma. DISCUSSION: Schwannomas of the base of the tongue are rare and should be included in the differential diagnosis based on the imaging features and enhancem ent pattern. CONCLUSION: Imaging features, particularly MRI with contrast helps in differentiating benign from malignant lesions of the base of the tongue. Schwannomas are benign and have good prognosis as they can be excised when compared to the other intraoral malignant lesions.

  12. 膝关节三维有限元模型的构建及生物力学分析%Establishment and Biomechanical Analysis of a 3-D Finite Element Model of the Knee

    Institute of Scientific and Technical Information of China (English)

    李杏芮; 陈清; 盛华均; 杨美; 吕发金; 李信友; 梁熙

    2015-01-01

    Objective:To establish a three-dimensional finite element analysis model of the knee joint to be used on the ordinary computer and then to do a preliminary biomechanical analysis ,w hich could provide a simulated foundation for personalized prosthesis design and 3-D printing .Methods :CT scan results of healthy adult volunteers were imported into Mimics software to set up a three-dimensional model ,and then were imported into ANSYS software to establish the three-dimensional finite element model by defi-ning a unit type ,choosing material properties and meshing .Results:The three-dimensional finite element model was mimic and clear which could be used on the ordinary computer .Mechanics analysis results showed that the main stress on the knee extension position was minimum .Conclusion :Based on Mimics and ANSYS software ,a three-dimensional finite element model of the knee joint was established success-fully which could be applied on a personal computer .Biomechanical analysis of the model showed that in personalized design of the shape of the knee implant ,the patient's own knee extension position should be taken for reference .%目的 :构建一个能在普通计算机上使用的膝关节三维有限元模型 ,并进行初步生物力学分析 ,为个性化假体设计及3D打印提供仿真基础 .方法 :对健康成人志愿者进行CT扫描 ,导入Mimics软件中建立三维模型 ,再导入ANSYS软件中 ,通过定义单元类型、选择材料属性和划分网格 ,建立三维有限元模型 .结果 :三维有限元模型逼真、清晰、数据量小 ,适用于普通计算机 ;力学分析结果显示膝关节在伸直位时主应力最小 .结论 :基于Mimics及ANSYS软件 ,成功构建了能够在个人计算机上应用的膝关节三维有限元模型 ,对该模型生物力学分析显示 ,在个性化膝关节假体设计时 ,其形态应以病人自身膝关节伸直位为参考依据 .

  13. Waveform effects of a metastable olivine tongue in subducting slabs

    Science.gov (United States)

    Vidale, John E.; Williams, Quentin; Houston, Heidi

    1991-01-01

    Velocity models of subducting slabs with a kinetically-depressed olivine to beta- and gamma-spinel transition are constructed, and the effect that such structures would have on teleseismic P waveforms are examined using a full-wave finite-difference method. These 2D calculations yielded waveforms at a range of distances in the downdip direction. The slab models included a wedge-shaped, low-velocity metastable olivine tongue (MOTO) to a depth of 670 km, as well as a plausible thermal anomaly; one model further included a 10-km-thick fast layer on the surface of the slab. The principal effect of MOTO is to produce grazing reflections at wide angles off the phase boundary, generating a secondary arrival 0 to 4 seconds after the initial arrival depending on the take-off angle. The amplitude and timing of this feature vary with the lateral location of the seismic source within the slab cross-section.

  14. Enterobacteriaceae and pseudomonadaceae on the dorsum of the human tongue

    Directory of Open Access Journals (Sweden)

    Simone Conti

    2009-10-01

    Full Text Available OBJECTIVE: The aim of this study was to correlate the presence of Enterobacteriaceae, Pseudomonadaceae, Moraxellaceae and Xanthomonadaceae on the posterior dorsum of the human tongue with the presence of tongue coating, gender, age, smoking habit and denture use. MATERIAL AND METHODS: Bacteria were isolated from the posterior tongue dorsum of 100 individuals in MacConkey agar medium and were identified by the API 20E system (Biolab-Mérieux. RESULTS: 43% of the individuals, presented the target microorganisms on the tongue dorsum, with greater prevalence among individuals between 40 and 50 years of age (p = 0.001 and non-smokers (p=0.0485. CONCLUSIONS: A higher prevalence of Enterobacteriaceae and Pseudomonadaceae was observed on the tongue dorsum of the individuals evaluated. There was no correlation between these species and the presence and thickness of tongue coating, gender and presence of dentures.

  15. ENTEROBACTERIACEAE AND PSEUDOMONADACEAE ON THE DORSUM OF THE HUMAN TONGUE

    OpenAIRE

    Simone Conti; Silvana Soléo Ferreira dos Santos; Cristiane Yumi Koga-Ito; Antonio Olavo Cardoso Jorge

    2009-01-01

    OBJECTIVE: The aim of this study was to correlate the presence of Enterobacteriaceae, Pseudomonadaceae, Moraxellaceae and Xanthomonadaceae on the posterior dorsum of the human tongue with the presence of tongue coating, gender, age, smoking habit and denture use. MATERIAL AND METHODS: Bacteria were isolated from the posterior tongue dorsum of 100 individuals in MacConkey agar medium and were identified by the API 20E system (Biolab-Mérieux). RESULTS: 43% of the individuals, presented the targ...

  16. Base of tongue neurilemmoma: excision by transoral laser microsurgery.

    Science.gov (United States)

    Ballesteros, Ferran; Vilaseca, Isabel; Blanch, Jose Luis; Gaspa, Albert; Bernal-Sprekelsen, Manuel

    2007-09-01

    Benign and malignant tumors of the tongue base can be removed by various surgical approaches. A rare case of neurilemmoma of the base of the tongue removed by transoral laser microsurgery (TLM) is presented. Schwannomas in this area usually present as a slow-growing, painless mass on the tongue surface. In this case, fiberoptic examination and magnetic resonance imaging were crucial as first step studies to elucidate the biology of the lesion.

  17. Ancient schwannoma of the tongue: a case report.

    Science.gov (United States)

    Bilici, Suat; Akpınar, Meltem; Yiğit, Ozgür; Günver, Feray

    2011-01-01

    A 45-year-old male patient had left sided submucosal swelling extending backwards from the tip of the tongue disturbing articulation and swallowing. Submucosally located lesion was 3 x 2 x 1.5 cm in size and totally excised under local anesthesia. In this article, we present a case of ancient schwannoma of tongue. Although a very rare entity, ancient schwannoma should be considered in differential diagnosis of tongue lesions.

  18. Evaluation of healthy and sensory indexes of sweetened beverages using an electronic tongue.

    Science.gov (United States)

    Dias, Luís G; Sequeira, Cédric; Veloso, Ana C A; Sousa, Mara E B C; Peres, António M

    2014-10-27

    Overconsumption of sugar-sweetened beverages may increase the risk of health problems and so, the evaluation of their glycemic load and fructose-intolerance level is essential since it may allow establishing possible relations between physiologic effects of sugar-rich beverages and health. In this work, an electronic tongue was used to accurately classify beverages according to glycemic load (low, medium or high load) as well to their adequacy for people suffering from fructose malabsorption syndrome (tolerable or not): 100% of correct classifications (leave-one-out cross-validation) using linear discriminant models based on potentiomentric signals selected by a meta-heuristic simulated annealing algorithm. These results may be partially explained by the electronic tongue's capability to mimic the human sweetness perception and total acid flavor of beverages, which can be related with glycemic load and fructose-intolerance index. Finally, the E-tongue was also applied to quantify, accurately, healthy and sensory indexes using multiple linear regression models (leave-one-out cross-validation: Radj>0.99) in the following dynamic ranges: 4.7fructose intolerance index≤1.5; 32tongue could be used as a practical, fast, low-cost and green tool for beverage's healthy and sensory evaluation.

  19. Detection of antibiotic residues in bovine milk by a voltammetric electronic tongue system.

    Science.gov (United States)

    Wei, Zhenbo; Wang, Jun

    2011-05-23

    A voltammetric electronic tongue (VE-tongue) was developed to detect antibiotic residues in bovine milk. Six antibiotics (Chloramphenicol, Erythromycin, Kanamycin sulfate, Neomycin sulfate, Streptomycin sulfate and Tetracycline HCl) spiked at four different concentration levels (0.5, 1, 1.5 and 2 maximum residue limits (MRLs)) were classified based on VE-tongue by two pattern recognition methods: principal component analysis (PCA) and discriminant function analysis (DFA). The VE-tongue was composed of five working electrodes (gold, silver, platinum, palladium, and titanium) positioned in a standard three-electrode configuration. The Multi-frequency large amplitude pulse voltammetry (MLAPV) which consisted of four segments (1 Hz, 10 Hz, 100 Hz and 1000 Hz) was applied as potential waveform. The six antibiotics at the MRLs could not be separated from bovine milk completely by PCA, but all the samples were demarcated clearly by DFA. Three regression models: Principal Component Regression Analysis (PCR), Partial Least Squares Regression (PLSR), and Least Squares-Support Vector Machines (LS-SVM) were used for concentrations of antibiotics prediction. All the regression models performed well, and PCR had the most stable results.

  20. Detection of antibiotic residues in bovine milk by a voltammetric electronic tongue system

    Energy Technology Data Exchange (ETDEWEB)

    Wei Zhenbo [Zhejiang University, Department of Bio-Systems Engineering, 268 Kaixuan Road, Hangzhou, Zhejiang 310029 (China); Wang Jun, E-mail: jwang@zju.edu.cn [Zhejiang University, Department of Bio-Systems Engineering, 268 Kaixuan Road, Hangzhou, Zhejiang 310029 (China)

    2011-05-23

    A voltammetric electronic tongue (VE-tongue) was developed to detect antibiotic residues in bovine milk. Six antibiotics (Chloramphenicol, Erythromycin, Kanamycin sulfate, Neomycin sulfate, Streptomycin sulfate and Tetracycline HCl) spiked at four different concentration levels (0.5, 1, 1.5 and 2 maximum residue limits (MRLs)) were classified based on VE-tongue by two pattern recognition methods: principal component analysis (PCA) and discriminant function analysis (DFA). The VE-tongue was composed of five working electrodes (gold, silver, platinum, palladium, and titanium) positioned in a standard three-electrode configuration. The Multi-frequency large amplitude pulse voltammetry (MLAPV) which consisted of four segments (1 Hz, 10 Hz, 100 Hz and 1000 Hz) was applied as potential waveform. The six antibiotics at the MRLs could not be separated from bovine milk completely by PCA, but all the samples were demarcated clearly by DFA. Three regression models: Principal Component Regression Analysis (PCR), Partial Least Squares Regression (PLSR), and Least Squares-Support Vector Machines (LS-SVM) were used for concentrations of antibiotics prediction. All the regression models performed well, and PCR had the most stable results.

  1. Functional morphology of the tongue in the nutcracker (Nucifraga caryocatactes).

    Science.gov (United States)

    Jackowiak, Hanna; Skieresz-Szewczyk, Kinga; Kwieciński, Zbigniew; Trzcielińska-Lorych, Joanna; Godynicki, Szymon

    2010-07-01

    The nutcracker Nucifraga caryocatactes belongs to a group of bird species that use their beak and tongue as tools for obtaining food, such as seeds from hard-to-reach cones or nuts from shells. The aim of the present study, carried out with a scanning electron microscope, was to define the morphological features of the tongue of the nutcracker, which seems to be adapted to its environment through specific methods of obtaining food. One of the characteristic features of the nutcracker's tongue is the unique structure of the anterior part of the tongue, which has two long and highly keratinized processes - a product of the renewable keratinized layer of the epithelium covering the ventral surface of the tongue. These dagger-like processes, which are a modified "lingual nail," take a major role in levering up and shelling seeds, which are transported over the short sulcus-shaped body of the tongue. A unique feature of the nutcracker's tongue is the groove separating the body from the root. Two rows of highly keratinized, mechanical, conical papillae are located at the junction of the body and the root. These papillae are mechanically protective elements for passing food particles in the form of seeds. Among lingual glands, only the posterior lingual glands on the root of the tongue have been observed. Their secretion agglutinates dry food before it is swallowed. Results of the present study indicate that the nutcracker's tongue is an efficient tool resembling a lever that is helpful in shelling seeds.

  2. The role of extensional viscosity in frog tongue projection

    Science.gov (United States)

    Noel, Alexis; Wagner, Caroline; McKinley, Gareth; Mendelson, Joe; Hu, David

    2014-11-01

    Frogs and other amphibians capture insects through high-speed tongue projection, some achieving tongue accelerations of over fifty times gravity. In this experimental study, we investigate how a frog's sticky saliva enables high-speed prey capture. At the Atlanta zoo, we used high-speed video to film the trajectory of frog tongues during prey capture. We have also designed and built a portable extensional rheometer; by following the capillary-driven thinning in the diameter of a thread of saliva we characterize the relaxation time and extensional viscosity and so infer the adhesive force between the frog tongue and prey.

  3. Relationship between tongue positions and formant frequencies in female speakers.

    Science.gov (United States)

    Lee, Jimin; Shaiman, Susan; Weismer, Gary

    2016-01-01

    This study examined the relationship (1) between acoustic vowel space and the corresponding tongue kinematic vowel space and (2) between formant frequencies (F1 and F2) and tongue x-y coordinates for the same time sampling point. Thirteen healthy female adults participated in this study. Electromagnetic articulography and synchronized acoustic recordings were utilized to obtain vowel acoustic and tongue kinematic data across ten speech tasks. Intra-speaker analyses showed that for 10 of the 13 speakers the acoustic vowel space was moderately to highly correlated with tongue kinematic vowel space; much weaker correlations were obtained for inter-speaker analyses. Correlations of individual formants with tongue positions showed that F1 varied strongly with tongue position variations in the y dimension, whereas F2 was correlated in equal magnitude with variations in the x and y positions. For within-speaker analyses, the size of the acoustic vowel space is likely to provide a reasonable inference of size of the tongue working space for most speakers; unfortunately there is no a priori, obvious way to identify the speakers for whom the covariation is not significant. A second conclusion is that F1 variations reflect tongue height, but F2 is a much more complex reflection of tongue variation in both dimensions.

  4. Virtual anthropology meets biomechanics.

    Science.gov (United States)

    Weber, Gerhard W; Bookstein, Fred L; Strait, David S

    2011-05-17

    A meeting in Vienna in October 2010 brought together researchers using Virtual Anthropology (VA) and Finite Element Analysis (FEA) in order to explore the benefits and problems facing a collaboration between the two fields. FEA is used to test mechanical hypotheses in functional anatomy and VA complements and augments this process by virtue of its tools for acquiring data, for segmenting and preparing virtual specimens, and for generating reconstructions and artificial forms. This represents a critical methodological advance because geometry is one of the crucial inputs of FEA and is often the variable of interest in functional anatomy. However, we currently lack tools that quantitatively relate differences in geometry to differences in stress and strain, or that evaluate the impact on FEA of variation within and between biological samples. Thus, when comparing models of different geometry, we do not currently obtain sufficiently informative answers to questions such as "How different are these models, and in what manner are they different? Are they different in some anatomical regions but not others?" New methodologies must be developed in order to maximize the potential of FEA to address questions in comparative and evolutionary biology. In this paper we review these and other important issues that were raised during our Vienna meeting.

  5. Applied Biomechanics in an Instructional Setting

    Science.gov (United States)

    Hudson, Jackie L.

    2006-01-01

    Biomechanics is the science of how people move better, meaning more skillfully and more safely. This article places more emphasis on skill rather than safety, though there are many parallels between them. It shares a few features of the author's paradigm of applied biomechanics and discusses an integrated approach toward a middle school football…

  6. Biomechanical properties of four dermal substitutes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Guo-an; NING Fang-gang; ZHAO Nan-ming

    2007-01-01

    @@ Many kinds of cell-free dermal substitutes have been developed during the past several years, however,their biomechanical properties, including hysteresis,stress relaxation, creep, and non-linear stress-strain, are still unknown. In this study, we tested these biomechanical characteristics of four dermal substitutes,and compared them with those of fresh human skin (FHS).

  7. [Ergonomy--dentistry--biomechanics].

    Science.gov (United States)

    Catović, E; Kraljević, K; Satović, A

    1990-01-01

    In this paper the authors present with scientifically--critically looking, ergonomicas--in interdisciplinary group of applied sciences, show the outstanding possibilities of complete analysis and improvement of "man--machine--environment system". With a scientific approach and use of the latest principles of modern ergonomics, the term of dental ergonomics is introduced in dental medicine. It particularly refers to the creation of different models of dental equipment, instruments and working areas, as well as to the investigation of the harmful factors and the effects of working environment on the dentist's health, especially, on the locomotor system which is mostly affected within the "dentist/patient/--equipment--environment system". In conclusion the authors pointed to the fact that there are still so many uninvestigated questions and problems related to dental ergonomics.

  8. Biomechanical analysis of the camelid cervical intervertebral disc

    Directory of Open Access Journals (Sweden)

    Dean K. Stolworthy

    2015-01-01

    Full Text Available Chronic low back pain (LBP is a prevalent global problem, which is often correlated with degenerative disc disease. The development and use of good, relevant animal models of the spine may improve treatment options for this condition. While no animal model is capable of reproducing the exact biology, anatomy, and biomechanics of the human spine, the quality of a particular animal model increases with the number of shared characteristics that are relevant to the human condition. The purpose of this study was to investigate the camelid (specifically, alpaca and llama cervical spine as a model of the human lumbar spine. Cervical spines were obtained from four alpacas and four llamas and individual segments were used for segmental flexibility/biomechanics and/or morphology/anatomy studies. Qualitative and quantitative data were compared for the alpaca and llama cervical spines, and human lumbar specimens in addition to other published large animal data. Results indicate that a camelid cervical intervertebral disc (IVD closely approximates the human lumbar disc with regard to size, spinal posture, and biomechanical flexibility. Specifically, compared with the human lumbar disc, the alpaca and llama cervical disc size are approximately 62%, 83%, and 75% with regard to area, depth, and width, respectively, and the disc flexibility is approximately 133%, 173%, and 254%, with regard to range of motion (ROM in axial-rotation, flexion-extension, and lateral-bending, respectively. These results, combined with the clinical report of disc degeneration in the llama lower cervical spine, suggest that the camelid cervical spine is potentially well suited for use as an animal model in biomechanical studies of the human lumbar spine.

  9. Classification and prediction of rice wines with different marked ages by using a voltammetric electronic tongue.

    Science.gov (United States)

    Wei, Zhenbo; Wang, Jun; Ye, Linshuang

    2011-08-15

    A voltammetric electronic tongue (VE-tongue) was developed to discriminate the difference between Chinese rice wines in this research. Three types of Chinese rice wine with different marked ages (1, 3, and 5 years) were classified by the VE-tongue by principal component analysis (PCA) and cluster analysis (CA). The VE-tongue consisted of six working electrodes (gold, silver, platinum, palladium, tungsten, and titanium) in a standard three-electrode configuration. The multi-frequency large amplitude pulse voltammetry (MLAPV), which consisted of four segments of 1 Hz, 10 Hz, 100 Hz, and 1000 Hz, was applied as the potential waveform. The three types of Chinese rice wine could be classified accurately by PCA and CA, and some interesting regularity is shown in the score plots with the help of PCA. Two regression models, partial least squares (PLS) and back-error propagation-artificial neural network (BP-ANN), were used for wine age prediction. The regression results showed that the marked ages of the three types of Chinese rice wine were successfully predicted using PLS and BP-ANN.

  10. Correlation between CCR7 expression and lymph node metastatic potential of human tongue carcinoma.

    Science.gov (United States)

    Xia, X; Liu, K; Zhang, H; Shang, Z

    2015-01-01

    Metastasis is an important cause of cancer-related mortality. In this study, we investigated the role of CCR7 in the lymph node metastasis of tongue carcinoma. Immunohistochemistry and Western blot revealed the expression of CCR7 in tongue SCC tissues and cell lines. In addition, we examined the expression of CCL21, a ligand of CCR7, in normal and diseased lymph nodes using immunohistochemistry and/or real-time PCR. The CCR7 expression was significantly correlated with cervical lymph node metastasis, tumor staging, and histological grade (P = 0.015, 0.040, and 0.015, respectively). The multivariate analysis showed that regional lymph node metastasis, the expression of CCR7, and LVD were the independent poor prognostic factors. Knockdown of CCR7 gene resulted in a significant inhibition of migration and invasion of SCC4 cells in vitro without affecting the proliferation and apoptosis of tumor cells. Also, CCR7 knockdown obviously inhibited cervical lymph node metastasis in an animal tumor model. Our study indicated that CCR7 may play an important role in progression of tongue SCC and could be a promising target for tongue SCC therapy.

  11. Segmentation algorithms for ear image data towards biomechanical studies.

    Science.gov (United States)

    Ferreira, Ana; Gentil, Fernanda; Tavares, João Manuel R S

    2014-01-01

    In recent years, the segmentation, i.e. the identification, of ear structures in video-otoscopy, computerised tomography (CT) and magnetic resonance (MR) image data, has gained significant importance in the medical imaging area, particularly those in CT and MR imaging. Segmentation is the fundamental step of any automated technique for supporting the medical diagnosis and, in particular, in biomechanics studies, for building realistic geometric models of ear structures. In this paper, a review of the algorithms used in ear segmentation is presented. The review includes an introduction to the usually biomechanical modelling approaches and also to the common imaging modalities. Afterwards, several segmentation algorithms for ear image data are described, and their specificities and difficulties as well as their advantages and disadvantages are identified and analysed using experimental examples. Finally, the conclusions are presented as well as a discussion about possible trends for future research concerning the ear segmentation.

  12. Biomechanical performance of orthopedic gloves.

    Science.gov (United States)

    Jackson, E M; Neal, J G; Williams, F M; Stern, C A; Suber, F; Thacker, J G; Edlich, R F

    1999-01-01

    The purpose of this study was to compare the biomechanical performance of commercially available orthopedic gloves to that of a single surgical glove, as well as a double glove system. The orthopedic gloves were found to be thicker than the single surgical glove. This increased thickness of the orthopedic glove was associated with a greater resistance to glove puncture. The thickest orthopedic gloves also had reduced tactile sensitivity when compared to the single surgical glove. In addition, the glove donning forces and glove hydration rates varied considerably. These latter biomechanical performance parameters were not significantly related to glove thickness. The double glove systems tested in this study had similar performance characteristics in regard to many of the orthopedic gloves. The glove donning forces for the double glove systems were the lowest of the gloves tested. In addition, the double glove systems displayed the greatest resistance to glove hydration of the gloves tested. Their performance in the glove hydration tests and the force required to don the double glove systems were much more desirable than any of the orthopedic gloves. The results of this study indicate that the double glove systems may provide a desirable alternative to the use of the single orthopedic gloves.

  13. Repeated tongue lift movement induces neuroplasticity in corticomotor control of tongue and jaw muscles in humans

    DEFF Research Database (Denmark)

    Komoda, Yoshihiro; Lida, Takashi; Kothari, Mohit

    2015-01-01

    latencies. FDI MEP parameters (amplitude, threshold, area, latency) were not significantly different between the four sessions. Our findings suggest that repeated TLT can trigger neuroplasticity reflected in increased excitability of the corticomotor representation of not only the tongue muscles but also...

  14. Effects of tongue position and lung volume on voluntary maximal tongue protrusion force in humans.

    Science.gov (United States)

    Saboisky, Julian P; Luu, Billy L; Butler, Jane E; Gandevia, Simon C

    2015-01-15

    Maximal voluntary protrusion force of the human tongue has not been examined in positions beyond the incisors or at different lung volumes. Tongue force was recorded with the tongue tip at eight positions relative to the incisors (12 and 4mm protrusion, neutral and 4, 12, 16, 24 and 32mm retraction) at functional residual capacity (FRC), total lung capacity (TLC) and residual volume (RV) in 15 healthy subjects. Maximal force occurred between 12mm and 32mm retraction (median 16mm). Maximum force at FRC was reproducible at the optimal tongue position across sessions (P=0.68). Across all positions at FRC the average force was highest at 24mm retraction (28.3±5.3N, mean±95% CI) and lowest at 12mm protrusion (49.1±4.6% maximum; Ptongue positions, maximal force was on average 9.3% lower at FRC than TLC and RV (range: 4.5-12.7% maximum, P<0.05). Retracted positions produce higher-force protrusions with a small effect of lung volume.

  15. Prosthetic abutment influences bone biomechanical behavior of immediately loaded implants

    OpenAIRE

    Camargos, Germana de Villa; SOTTO-MAIOR,Bruno Salles; Silva,Wander José da; Priscilla Cardoso LAZARI; Del Bel Cury, Altair Antoninha

    2016-01-01

    Abstract This study aimed to evaluate the influence of the type of prosthetic abutment associated to different implant connection on bone biomechanical behavior of immediately and delayed loaded implants. Computed tomography-based finite element models comprising a mandible with a single molar implant were created with different types of prosthetic abutment (UCLA or conical), implant connection (external hexagon, EH or internal hexagon, IH), and occlusal loading (axial or oblique), for both i...

  16. 一个人膝关节弹性咬合接触的生物力学模型%A Biomechanical Model of Human Knee-Joint Elastic Articulate Contact

    Institute of Scientific and Technical Information of China (English)

    王西十; TurgutTumer; 等

    2001-01-01

    In this paper, based on the characterizations of human knee-joint anatomical structures and reports of the literature and experiments, a biomechanical model of the human knee-joint elastic articulate contact is developed under the conditions of sampling the human knee-joints. This model is believed to be a powerful tool for functional analysis of the knee, for evaluation of surgical and diagnostic procedures and for design of artificial joints.%基于人膝关节的解剖特征,在文献和试验的基础上,对膝关节解剖结构作了适当的简化,从而根据赫茨理论,建立了膝关节股骨与胫骨弹性咬合接触的生物力学模型,并获得了膝关节弹性咬合接触的最大咬合接触应力、咬合接触面积和相对咬合接触变形的定解形式。这些解的结果,对于指导临床诊断和治疗膝关节病等均具有重要作用。

  17. Repair of large palatal fistula using tongue flap

    Directory of Open Access Journals (Sweden)

    Fejjal Nawfal

    2014-01-01

    Full Text Available Large palatal fistulas are a challenging problem in cleft surgery. Many techniques are used to close the defect. The tongue flap is an easy and reproductible procedure for managing this complication. The authors report a case of a large palatal fistula closure with anteriorly based tongue flap.

  18. Mother Tongue and Education in Africa: Publicising the Reality

    Science.gov (United States)

    Kioko, Angelina N.; Ndung'u, Ruth W.; Njoroge, Martin C.; Mutiga, Jayne

    2014-01-01

    Varied realities surround the use of mother tongue education in Africa. These realities are entrenched in the attitudes and misconceptions that have gone unchallenged due to inadequate literature on the successful use of mother tongues in the classroom and beyond. The realities discussed in this paper include the frustrations of children…

  19. Tongue Measures in Individuals with Normal and Impaired Swallowing

    Science.gov (United States)

    Stierwalt, Julie A. G.; Youmans, Scott R.

    2007-01-01

    Purpose: This investigation sought to add to the extant literature on measures of normal tongue function, to provide information on measures of tongue function in a group of individuals with oral phase dysphagia, and to provide a comparison of these 2 groups matched for age and gender. Method: The Iowa Oral Performance Instrument was utilized to…

  20. Spatiotemporal Coupling of the Tongue in Amyotrophic Lateral Sclerosis

    Science.gov (United States)

    Kuruvilla, Mili S.; Green, Jordan R.; Yunusova, Yana; Hanford, Kathy

    2012-01-01

    Purpose: The primary aim of the investigation was to identify deficits in spatiotemporal coupling between tongue regions in amyotrophic lateral sclerosis (ALS). The relations between disease-related changes in tongue movement patterns and speech intelligibility were also determined. Methods: The authors recorded word productions from 11…

  1. Extremely high-power tongue projection in plethodontid salamanders

    NARCIS (Netherlands)

    Deban, S.M.; O'Reilly, J.C.; Dicke, U.; Leeuwen, van J.L.

    2007-01-01

    Many plethodontid salamanders project their tongues ballistically at high speed and for relatively great distances. Capturing evasive prey relies on the tongue reaching the target in minimum time, therefore it is expected that power production, or the rate of energy release, is maximized during tong

  2. Pedagogical Competencies for Mother-Tongue Teacher Education

    Science.gov (United States)

    Mata, Liliana

    2014-01-01

    This study aims to elaborate a framework for both the foundation and application of professional standards for mother-tongue teachers. The main issue with which this study is concerned constitutes the lack of a set of clear standards for the initial training of mother-tongue teachers. In terms of theory, that which has currently been analyzed in…

  3. Evaluation of Manometric Measures during Tongue-Hold Swallows

    Science.gov (United States)

    Doeltgen, Sebastian H.; Witte, Ulrike; Gumbley, Freya; Huckabee, Maggie-Lee

    2009-01-01

    Purpose: Based on visual inspection, prior research documented increased movement of the posterior pharyngeal wall in healthy volunteers during tongue-hold swallows. This manometric study investigated the immediate effects of the tongue-hold maneuver on pharyngeal peak pressure generation, duration of pressure generation, and pressure slope…

  4. Malignant melanoma of the tongue following low-dose radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kalemeris, G.C.; Rosenfeld, L.; Gray, G.F. Jr.; Glick, A.D.

    1985-03-01

    A 47-year-old man had a spindly malignant melanoma of the tongue many years after low-dose radiation therapy for lichen planus. To our knowledge, only 12 melanomas of the tongue have been reported previously, and in none of these was radiation documented.

  5. The Use of Mother Tongue in Second Language Teaching

    Institute of Scientific and Technical Information of China (English)

    赵鸣霄; 张立杰

    2015-01-01

    This paper explores the specific application of mother tongue in Second Language learning from the perspective of class management, introducing learning methods, teaching vocabulary, teaching grammar, dealing with exercises and testing, and cooperation among students. It is concluded that mother tongue should be properly used in Second Language Teaching in or-der to improve the teaching of second language.

  6. 膝关节半月板三维有限元模型的动态仿真生物力学分析%Biomechanical analysis of dynamic simulation of three dimensional finite element models of knee joint meniscus

    Institute of Scientific and Technical Information of China (English)

    陈文栋; 杨光

    2016-01-01

    volunteers, the medicine finite element simulation software Mimics10.01 and reverse engineering software Rapidform XOR3 were utilized to reconstruct three-dimensional finite element model of knee joint meniscus. The advanced finite element analysis software Abaqus6.10-1 was utilized for analogue simulation and for analyzing biomechanical changes during flexion under vertical load of 300 N. RESULTS AND CONCLUSION:(1) While the knee joint flexed at 0°, 30°, 60° and 90°, with the increase of angle, maximum stress point moved from the anterior edge of tibia attachment surface of the medial meniscus posterior angle to the posterior edge of tibia attachment surface of the lateral meniscus anterior angle, and the stress range of lateral meniscus was greater than that of the medial meniscus. (2) The maximal displacement point moved from the midpoint of inner edge of the medial meniscus to the front outer-upper edge of the lateral meniscus at knee flexion of 0°, 30°, 60° and 90°. Moreover, the range of displacement of lateral meniscus was bigger than the medial meniscus. (3) These findings suggest that the meniscus is the major bearing structure in the process of knee flexion. The lateral meniscus injury rate is greater than the medial meniscus in process of exercise, which is associated with large stress and displacement.

  7. Biomechanical simulation of high-heeled shoe donning and walking.

    Science.gov (United States)

    Yu, Jia; Cheung, Jason Tak-Man; Wong, Duo Wai-Chi; Cong, Yan; Zhang, Ming

    2013-08-09

    Footwear serves to protect the foot in various activities, to enhance athletic performance in sports and in many cases to fulfill aesthetic and cultural needs of urban society. Most women like wearing high-heeled shoes (HHS) for the benefit of sensuous attractiveness, while foot problems are often associated. Computational modeling based on finite element (FE) analysis is a useful tool for deep understanding of foot and footwear biomechanics and incorporating footwear with foot in the model is the prerequisite. In this study, a three-dimensional FE model of coupled foot-ankle-shoe complex and preceding gait simulation were established. Interfacial contact simulation was employed to complete the donning process of foot and shoe upper contact. Three major stance phases namely heel strike, midstance and push off were simulated to investigate the biomechanical response of high-heeled shod walking. It was found that the contact pressure at all metatarsophalangeal (MTP) joints intensified and reached their maximum at push off phase during locomotion, meanwhile the first MTP had the largest magnitude. The first and fifth MTP joints had larger movements in transverse plane among all MTP joints, indicating that these two joints bended more significantly by toe box restraint during locomotion. The dorsal contact pressure at the first toe increased by four times from heel strike to push off. The established HHS donning and walking simulation in this study proved the versatility and promising potential of computational approach for realistic biomechanical evaluation and optimization of footwear design in a virtual environment.

  8. Taste masking analysis in pharmaceutical formulation development using an electronic tongue.

    Science.gov (United States)

    Zheng, Jack Y; Keeney, Melissa P

    2006-03-09

    The purpose of this study is to assess the feasibility for taste masking and comparison of taste intensity during formulation development using a multichannel taste sensor system (e-Tongue). Seven taste sensors used in the e-Tongue were cross-selective for five basic tastes while having different sensitivity or responsibility for different tastes. Each of the individual sensors concurrently contributes to the detection of most substances in a complicated sample through the different electronic output. Taste-masking efficiency was evaluated using quinine as a bitter model compound and a sweetener, acesulfame K, as a bitterness inhibitor. In a 0.2 mM quinine solution, the group distance obtained from e-Tongue analysis was reduced with increasing concentration of acesulfame K. This result suggests that the sensors could detect the inhibition of bitterness by a sweetener and could be used for optimization of the sweetener level in a liquid formulation. In addition, the bitterness inhibition of quinine by using other known taste-masking excipients including sodium acetate, NaCl, Prosweet flavor, and Debittering powder or soft drinks could be detected by the e-Tongue. These results further suggest that the e-Tongue should be useful in a taste-masking evaluation study on selecting appropriate taste-masking excipients for a solution formulation or a reconstitution vehicle for a drug-in-bottle formulation. In another study, the intensity of the taste for several drug substances known to be bitter was compared using the e-Tongue. It was found that the group distance was 695 for prednisolone and 686 for quinine, which is much higher than that of caffeine (102). These results indicate that the taste of prednisolone and quinine is stronger or more bitter than that of caffeine as expected. Based on the group distance, the relative intensity of bitterness for these compounds could be ranked in the following order: ranitidine HCl>prednisolone Na>quinine HCl approximately

  9. Training induced cortical plasticity compared between three tongue training paradigms

    DEFF Research Database (Denmark)

    Kothari, Mohit; Svensson, Peter; Jensen, Jim

    2013-01-01

    The primary aim of this study was to investigate the effect of different training types and secondary to test gender differences on the training-related cortical plasticity induced by three different tongue training paradigms: 1. Therapeutic tongue exercises (TTE), 2. Playing computer games......) (control) were established using transcranial magnetic stimulation (TMS) at three time-points: (1) before tongue training, (2) immediately after training, (3) 1 h after training. Subject-based reports of motivation, fun, pain and fatigue were evaluated on 0-10 numerical rating scales (NRS) after training......-points. No significant effect of tongue training on FDI MEPs was observed (P>0.335). The tongue cortical motor map areas were not significantly increased by training (P>0.142). Training with TDS was most motivating and fun (Plevel was not different between groups...

  10. Tongue piercing by a Yogi: QEEG observations.

    Science.gov (United States)

    Peper, Erik; Wilson, Vietta E; Gunkelman, Jay; Kawakami, Mitsumasa; Sata, Misa; Barton, William; Johnston, James

    2006-12-01

    : This study reports on the QEEG observations recorded from a yogi during tongue piercing in which he demonstrated voluntary pain control. The QEEG was recorded with a Lexicor 1620 from 19 sites with appropriate controls for impedence and artifacts. A neurologist read the data for abnormalities and the QEEG was analyzed by mapping, single and multiple hertz bins, coherence, and statistical comparisons with a normative database. The session included a meditation baseline and tongue piercing. During the meditative baseline period the yogi's QEEG maps suggesting that he was able to lower his brain activity to a resting state. This state showed a predominance of slow wave potentials (delta) during piercing and suggested that the yogi induced a state that may be similar to those found when individuals are under analgesia. Further research should be conducted with a group of individuals who demonstrate exceptional self-regulation to determine the underlying mechanisms, and whether the skills can be used to teach others how to manage pain.

  11. Base of Tongue Tuberculosis: A Case Report

    Directory of Open Access Journals (Sweden)

    Prepageran Narayanan

    2012-02-01

    Full Text Available We report a rare case of base of tongue tuberculosis following pulmonary tuberculosis. Patient presented to us with chief complaints of sore throat and pain on swallowing for period of 3 months. On examination with 70 degree telescope, we observed an ulcer on right side of base of tongue. The edges of the ulcer appeared to be undermined with whitish slough at the centre of the ulcer. Examination of neck showed a multiple small palpable middle deep cervical lymph nodes on right side of neck. Biopsy of the ulcer was taken, which showed granulomatous inflammation, suggestive of tuberculosis. Laboratory investigations revealed a raise in erythrocyte sedimentation rate, sputum for acid fast bacilli was strongly positive. Chest X ray was performed for patient showed multiple areas of consolidation. Patient was referred to chest clinic for further management of tuberculosis and was started on anti-tuberculous drugs. In conclusion tuberculosis of oral cavity is rare, but should be considered among one of the differential diagnosis of the oral lesions and biopsy is necessary to confirm the diagnosis.

  12. Biomechanics and analysis of running gait.

    Science.gov (United States)

    Dugan, Sheila A; Bhat, Krishna P

    2005-08-01

    Physical activity, including running, is important to general health by way of prevention of chronic illnesses and their precursors. To keep runners healthy, it is paramount that one has sound knowledge of the biomechanics of running and assessment of running gait. More so, improving performance in competitive runners is based in sound training and rehabilitation practices that are rooted firmly in biomechanical principles. This article summarized the biomechanics of running and the means with which one can evaluate running gait. The gait assessment techniques for collecting and analyzing kinetic and kinematic data can provide insights into injury prevention and treatment and performance enhancement.

  13. Prosthetic abutment influences bone biomechanical behavior of immediately loaded implants.

    Science.gov (United States)

    Camargos, Germana de Villa; Sotto-Maior, Bruno Salles; Silva, Wander José da; Lazari, Priscilla Cardoso; Del Bel Cury, Altair Antoninha

    2016-05-31

    This study aimed to evaluate the influence of the type of prosthetic abutment associated to different implant connection on bone biomechanical behavior of immediately and delayed loaded implants. Computed tomography-based finite element models comprising a mandible with a single molar implant were created with different types of prosthetic abutment (UCLA or conical), implant connection (external hexagon, EH or internal hexagon, IH), and occlusal loading (axial or oblique), for both immediately and delayed loaded implants. Analysis of variance at 95%CI was used to evaluate the peak maximum principal stress and strain in bone after applying a 100 N occlusal load. The results showed that the type of prosthetic abutment influences bone stress/strain in only immediately loaded implants. Attachment of conical abutments to IH implants exhibited the best biomechanical behavior, with optimal distribution and dissipation of the load in peri-implant bone.

  14. Prosthetic abutment influences bone biomechanical behavior of immediately loaded implants

    Directory of Open Access Journals (Sweden)

    Germana de Villa CAMARGOS

    2016-01-01

    Full Text Available Abstract This study aimed to evaluate the influence of the type of prosthetic abutment associated to different implant connection on bone biomechanical behavior of immediately and delayed loaded implants. Computed tomography-based finite element models comprising a mandible with a single molar implant were created with different types of prosthetic abutment (UCLA or conical, implant connection (external hexagon, EH or internal hexagon, IH, and occlusal loading (axial or oblique, for both immediately and delayed loaded implants. Analysis of variance at 95%CI was used to evaluate the peak maximum principal stress and strain in bone after applying a 100 N occlusal load. The results showed that the type of prosthetic abutment influences bone stress/strain in only immediately loaded implants. Attachment of conical abutments to IH implants exhibited the best biomechanical behavior, with optimal distribution and dissipation of the load in peri-implant bone.

  15. Smart Materials in Structural Health Monitoring, Control and Biomechanics

    CERN Document Server

    Soh, Chee-Kiong; Bhalla, Suresh

    2012-01-01

    "Smart Materials in Structural Health Monitoring, Control and Biomechanics" presents the latest developments in structural health monitoring, vibration control and biomechanics using smart materials. The book mainly focuses on piezoelectric, fibre optic and ionic polymer metal composite materials. It introduces concepts from the very basics and leads to advanced modelling (analytical/ numerical), practical aspects (including software/ hardware issues) and case studies spanning civil, mechanical and aerospace structures, including bridges, rocks and underground structures. This book is intended for practicing engineers, researchers from academic and R&D institutions and postgraduate students in the fields of smart materials and structures, structural health monitoring, vibration control and biomedical engineering. Professor Chee-Kiong Soh and Associate Professor Yaowen Yang both work at the School of Civil and Environmental Engineering, Nanyang Technological University, Singapore. Dr. Suresh Bhalla is an A...

  16. 有限元模型分析髓核摘除术后腰椎生物力学特性变化%Finite element model analysis of lumbar biomechanical characteristics after nucleus discectomy

    Institute of Scientific and Technical Information of China (English)

    李海波; 方杰; 陈其昕; 李方财; 唐小君

    2011-01-01

    目的 采用三维有限元模型分析方法,探讨腰椎间盘突出症髓核摘除术对腰椎生物力学特性的影响.方法 采用新型CAD方法精确建立腰椎L4~L5活动节段有限元模型,构建正常模型、退变模型、髓核摘除即刻模型和瘢痕长入模型,分别模拟正常椎间盘、退变椎间盘、髓核摘除术后即刻和术后中长期随访时的椎间盘,并在压缩、屈曲、伸展、前剪及后剪5种载荷条件下对4组模型进行生物力学测试.结果 (1)各种载荷下退变模型的腰椎节段刚度较正常模型提高;(2)髓核摘除即刻模型的刚度较退变模型减小,但较正常模型提高;(3)瘢痕长入模型腰椎节段刚度大幅回升并超过退变模型;(4)髓核摘除即刻模型在屈曲、后伸和后剪载荷下关节突接触力减小,瘢痕长入模型则表现为在后伸、前剪和后剪载荷下关节突接触力增加;(5)各种载荷下退变模型后向膨出度较正常模型明显减小,髓核摘除即刻模型后向膨出度一定程度回升,但其纤维环内环会发生"内向膨出".结论 腰椎间盘髓核摘除术可在术后不同时段对腰椎运动节段生物力学特性产生不同影响,髓核摘除术后即刻对腰椎稳定性和后部结构应力影响较小,而髓核摘除中长期后则可有腰椎运动节段变硬和关节突的应力增加.%Objective To use three-dimensional finite element model analysis for studying the lumbar biomechanical characteristics following nucleus discectomy in a patient with lumbar intervertebral disc protrusion. Methods A novel CAD method was adopted to accurately create the finite element models of L4/5 segment, including the models for normal disc, degenerated disc, denucleated disc immediately after operation (denucleated model), and denucleated disc after a longer time period (scar growth model). Furthermore, the biomechanical parameters of the four models were examined under five different loads, namely, compression

  17. [Biomechanics of the ankle joint].

    Science.gov (United States)

    Zwipp, H

    1989-03-01

    According to Fick, the tree-dimensional patterns of foot motion are best characterized as jawlike movement. Anatomically and biomechanically, this process represents conjoined, synchronous motion within the three mobile segments of the hindfoot: the ankle joint, the posterior subtalar joint, and the anterior subtalar joint. Foot kinematics can be described more completely if the anterior subtalar joint is defined not only as the talocalcaneal navicular joint, but as including the calcaneocuboid joint, thus representing the transverse joint of the tarsus, i.e., the Chopart joint. The axes of these three joints can be defined precisely. In some parts they represent a screwlike motion, clockwise or counter-clockwise, around the central ligamentous structures (fibulotibial ligament, talocalcaneal interosseous ligament, bifurcate ligament). The individual anatomy and structure of these ligaments provide variations in the degree and direction of foot motion. A precise knowledge of foot kinematics is important in surgical ligament and joint reconstruction and in selective foot arthrodeses.

  18. BIOMECHANIC EVALUATION OF CARPENTRY WORKERS IN THE DISTRITO FEDERAL, BRAZIL

    Directory of Open Access Journals (Sweden)

    Nilton Cesar Fiedler

    2010-08-01

    Full Text Available The aim of this study was the biomechanical assessment of carpentry woodworkers, located in Brasília, DF. It was filmed the profile of each worker during the performance of his activities in the carpentry and the forces involved in the work were assessed. The image of each woodworker was congealed to accomplish the measurement of articulation angles. The data were submitted to the software of posture analysis “Winowas” (OWAS Method and to the biomechanic model of posture prognosis and static forces, developed by Michigan University. The OWAS method showed that, for all machines and carpentries assessed, the worst posture occurred when the worker lifted and placed the pieces of wood on the floor and during the feeding in the smoother. The tridimensional biomechanic model registered the worst posture in different phases of the work cycle. In the first one, there were problems in all articulations, except the hips, when placing the pieces on the floor from the smoother. In the second one, there were problems in all articulations, except the elbows and the L5-S1 column disc, by feeding the surface planer. The third one, the ankles were the most injured when feeding the smoother, the surface planer, the circular saw and the band saw. According to the results, the woodworkers should try to eliminate the constant work standing upright, use auxiliary machinery to handle pieces of wood, reduce the load during feeding the machines and improve postures.

  19. Use of the smart tongue to monitor mold growth and discriminate between four mold species grown in liquid media

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Guangying, E-mail: zhaogy-user@163.com [Food Safety Key Lab of Zhejiang Province, Department of Food Quality and Safety, Zhejiang Gongshang University, Hangzhou 310035 (China); Lin Xiaona; Dou Wenchao; Tian Shiyi; Deng Shaoping; Shi Jinqin [Food Safety Key Lab of Zhejiang Province, Department of Food Quality and Safety, Zhejiang Gongshang University, Hangzhou 310035 (China)

    2011-04-01

    A novel voltammetric electronic tongue, smart tongue, was employed to monitor the growth of mold and to differentiate between four types of mold grown in liquid medium. Principal component analysis (PCA) was used to extract the relevant information obtained by the smart tongue. Reference growth curves were based on measurements of dry weight and pH. The growth detected by the smart tongue was basically consistent with that observed by the measurement of dry weight and pH. The optimal combinations of electrodes and frequencies for monitoring growth were as follows: for Aspergillus, both the Pt and Au electrodes at 1 Hz, 10 Hz and 100 Hz; for Penicillium, the Pt and W electrodes at 100 Hz; for Mucor, the Pt, Pd and W electrodes at the three frequency segments; for Rhizopus, the Pd, Ti and Ag electrodes at the three frequency segments. The Ag electrode at 10 Hz or 100 Hz frequency could differentiate well between the four types of mold for culturing 6 h in the liquid media. Therefore, the smart tongue has a promising future as a modern rapid analytical technology for the real time detection of the growth of mold and for the classification model of mold.

  20. THE CENTER FOR MILITARY BIOMECHANICS RESEARCH

    Data.gov (United States)

    Federal Laboratory Consortium — The Center for Military Biomechanics Research is a 7,500 ft2 dedicated laboratory outfitted with state-of-the-art equipment for 3-D analysis of movement, measurement...