The predominant model of the body in modern western medicine is the machine. Practitioners of the biomechanical model reduce the patient to separate, individual body parts in order to diagnose and treat disease. Utilization of this model has led, in part, to a quality of care crisis in medicine, in which patients perceive physicians as not sufficiently compassionate or empathic towards their suffering. Alternative models of the body, such as the phenomenological model, have been proposed to address this crisis. According (...) to the phenomenological model, the patient is viewed as an embodied person within a lived context and through this view the physician comes to understand the disruption illness causes in the patient’s everyday world of meaning. In this paper, I explore the impact these two models of the patient’s body have had on modern medical practice. To that end I first examine briefly the historical origins of the biomechanical and phenomenological models, providing a historical context for the discussion of each model’s main features in terms of machine-world and life-world. Next, I discuss the impact each model has had on the patient–physician relationship, and then I examine briefly the future development of each model. The meaning of illness vis-à-vis each model of the patient’s body is finally examined, especially in terms of how these two models affect the patient’s interpretation of illness. The paper concludes with a discussion of the biomechanical and phenomenological models, in terms of the quality of care crisis in modern western medicine. (shrink)

Solid Biomechanics is the first book to comprehensively review the mechanical design of organisms.

this study is to analyse the biomechanical influence of the been studied extensively, little is known how it is influclinical data on stability of the ankle joint. A two-dimenenced by the osseous joint configuration. Based on lateral..

The animal cell cytoskeleton consists of three interconnected filament systems: actin‐containing microfilaments (MFs), microtubules (MTs), and the lesser known intermediate filaments (IFs). All IF proteins share a common tripartite domain structure and the ability to assemble into 8–12 nm wide filaments. Electron microscopy data suggest that IFs are built according to a completely different plan from that of MFs and MTs. IFs are known to impart mechanical stability to cells and tissues but, until recently, the biomechanical properties of single IFs (...) were unknown. However, with the discovery of naturally occurring micrometer‐wide IF bundles and the development of new methodologies to mechanically probe single filaments, it is now possible to propose a more unified view of IF biomechanics. Unlike MFs and MTs, single IFs can now be described as flexible, extensible and tough, which has important implications for our understanding of cell and tissue mechanics. Furthermore, the molecular mechanisms at play when IFs are deformed point toward a pivotal role for them in mechanotransduction. BioEssays 29: 26–35, 2007. © 2006 Wiley Periodicals, Inc. (shrink)

Background and ObjectiveAbsolute angle represents the inclination of a body segment relative to a fixed reference in space. This work compares the absolute and relative angles for exploring biomechanical gait constraints.MethodsGait patterns of different neuromotor conditions were analyzed using 3D gait analysis: normal gait, Cerebral Palsy, Charcot Marie Tooth and Duchenne Muscular Dystrophy, representing central and peripheral nervous system and muscular disorders, respectively. Forty-two children underwent gait analysis: 10 children affected by CP, 10 children by CMT, 10 children by DMD (...) and 12 healthy children. The kinematic and kinetic parameters were collected to describe the biomechanical pattern of participants’ lower limbs. The absolute angles of thigh, leg and foot were calculated using the trigonometric relationship of the tangent. For each absolute series, the mean, range, maximum, minimum and initial contact were calculated. Kinematic and kinetic gait data were studied, and the results were compared with the literature.ResultsStatistical analysis of the absolute angles showed how, at the local level, the single segments behave differently depending on the pathology. However, if the lower limb is studied globally, a biomechanical constraint emerges.ConclusionEach segment compensates separately for the disease deficit so as to maintain a global biomechanical invariance. Using a model of inter-joint co-variation could improve the interpretation of the clinical gait pattern. (shrink)

ArgumentThis paper investigates whether there is a discrepancy between stated and actual aims in biomechanical research, particularly with respect to hypothesis testing. We present an analysis of one hundred papers recently published inThe Journal of Experimental BiologyandJournal of Biomechanics, and examine the prevalence of papers which have hypothesis testing as a stated aim, contain hypothesis testing claims that appear to be purely presentational, and have exploration as a stated aim. We found that whereas no papers had exploration as a (...) stated aim, 58 per cent of papers had hypothesis testing as a stated aim. We had strong suspicions, at the bare minimum, that presentational hypotheses were present in 31 per cent of the papers in this latter group. (shrink)

Bisphosphonates are a class of drugs which have shown good efficacy in the treatment of post‐menopausal osteoporosis, as well as a good safety profile. However, side‐effects such as risk for atypical femoral fractures (AFF) have appeared, leading to a decline in use of the drugs by many patients who would benefit from the treatment. While patient characteristics have contributed to improved understanding of risk factors, the mechanisms involved that explain AFF risk have not appeared. Recently, the possibility that the mechanism(s) (...) involved drug‐induced modification of cells of the nutrient canals of the femur and subsequent compromise in the bone matrix has been published. The present Hypothesis article builds on the concept presented earlier and expands into biomechanical considerations. An analogy of the mechanisms involved to a real‐life scenario is also presented. While this analogy has limitations, consideration of the biomechanical implications of progressive alterations to defects presented by compromised nutrient canal‐bone matrix also presents potential relationships with AFF risk. (shrink)

Leonardo da Vinci’s extensive drawings and notes devoted to anatomy do not arise in a medical context. He does not engage with surgery or “physic.” Rather, his aim is to reveal what he understood to be the divine engineering of God’s greatest creation. His earliest anatomical drawings map the conduits for the “spirits” at a deep level not practiced by other artists interested in the human body. The first set of drawings he produced in 1489 describes skulls with brilliant draftsmanship. (...) His notes for these drawings are predominantly concerned with the location of the “common sense” (sensus communis) at the geometrical center of the cranium. The next great set of drawings completed in ca. 1510 expounds the form and functions of the bones and muscles in meticulous mechanical detail, probably in collaboration with the young Paduan doctor, Marcantonio della Torre. Leonardo’s greatest realization of mathematics in anatomy comes when he looks at the valves of the heart; in studying the heart he also conceived a casting technique that he adapted to determine the form of the ventricles in the brain, radically revising the traditional arrangement of these structures. In a range of portrayals from diagrammatic to pictorial and from static to dynamic, Leonardo’s anatomical research is unrivalled in revealing the mechanics of the human body. His work in this context is an underappreciated precursor of the modern science of biomechanics. (Larger-sized versions of the Leonardo drawings presented here are available as supplementary material in the online version of this article.). (shrink)

The study of biomechanics most often takes a classic adaptationist approach, examining the functional abilities of organisms in relation to what is allowed by physical parameters. This approach generally assumes strong selection and is less concerned with evolutionary stochasticity in determining the presence of biological traits. It is equally important, however, to consider the importance of constraint in determining the form of organisms. If selection is relatively weak compared to stochastic events, then the observed forms in living systems can (...) be taken not as those shapes that were strongly selected for, so much as those forms that do not violate physical rules and therefore persist. Using the problem of maximum animal size as a case study for this alternative biomechanical philosophy, I demonstrate one example of how biomechanical approaches can be used to study constraint and consider the concept of absent forms. This alternative mindset and approach produces a complementary system to the traditional form and function approach in biomechanics. The two philosophies can be used in conjunction to better understand biological systems. I focus particularly on the maximum size of flying animals, as they are a heavily constrained class of system that has also been shaped by substantial stochasticity. (shrink)

Chondrocytes are specialised cells which produce and maintain the extracellular matrix of cartilage, a tissue that is resilient and pliant. In vivo, it has to withstand very high compressive loads, and that is explicable in terms of the physico‐chemical properties of cartilage‐specific macromolecules and with the movement of water and ions within the matrix. The functions of the cartilage‐specific collagens, aggrecan (a hydrophilic proteoglycan) and hyaluronan are discussed within this context. The structures of cartilage collagens and proteoglycans and their genes (...) are known and a number of informative mutations have been identified. In particular, collagen fibrillogenesis is a complex process which can be altered by mutations whose effects fit what is known about collagen molecular structural functions. In other instances, mutations have indicated new functions for particular molecular domains. As cartilage provides the template for the developing skeleton, mutations in genes for cartilage‐specific proteins often produce developmental abnormalities. The search for mutations amongst such genes in heritable disorders is being actively pursued by many groups, although mutation and phenotype are not always well correlated, probably because of compensatory mechanisms. The special nature of the chondrocyte is stressed in connection with its cell involvement in osteoarthritis, the most widespread disease of diarthrodial joints. (shrink)

The human masticatory system is a complex functional unit characterized by a multitude of skeletal components, muscles, soft tissues, and teeth. Muscle activation dynamics cannot be directly measured on live human subjects due to ethical, safety, and accessibility limitations. Therefore, estimation of muscle activations and their resultant forces is a longstanding and active area of research. Reinforcement learning (RL) is an adaptive learning strategy which is inspired by the behavioral psychology and enables an agent to learn the dynamics of an (...) unknown system via policy-driven explorations. The RL framework is a well-formulated closed-loop system where high capacity neural networks are trained with the feedback mechanism of rewards to learn relatively complex actuation patterns. In this work, we are building on a deep RL algorithm, known as the Soft Actor-Critic, to learn the inverse dynamics of a simulated masticatory system, i.e., learn the activation patterns that drive the jaw to its desired location. The outcome of the proposed training procedure is a parametric neural model which acts as the brain of the biomechanical system. We demonstrate the model’s ability to navigate the feasible three-dimensional (3D) envelope of motion with sub-millimeter accuracies. We also introduce a performance analysis platform consisting of a set of quantitative metrics to assess the functionalities of a given simulated masticatory system. This platform assesses the range of motion, metabolic efficiency, the agility of motion, the symmetry of activations, and the accuracy of reaching the desired target positions. We demonstrate how the model learns more metabolically efficient policies by integrating a force regularization term in the RL reward. We also demonstrate the inverse correlation between the metabolic efficiency of the models and their agility and range of motion. The presented masticatory model and the proposed RL training mechanism are valuable tools for the analysis of mastication and other biomechanical systems. We see this framework’s potential in facilitating the functional analyses aspects of surgical treatment planning and predicting the rehabilitation performance in post-operative subjects. (shrink)

Biomechanical engineering is marked by highly experimental efforts to craft mechanical devices that might one day alleviate the scarcity of transplantable organs in the USA. A pronounced desire among bioengineers involves melding humans with machines, bearing the promise of perfecting the natural yet messy flaws of the ‘natal’ body. Not all bodies are considered equal within this field, however. Visual renderings of heart devices — as an unusual sort of body prosthesis — foreground a specialized aesthetic, where the well-toned male (...) form defines an idealized generic of beauty and perfection. This analysis considers the moral underpinnings of the embodied aesthetic in specific reference to engineers’ efforts to fabricate implantable ‘artificial’ hearts. Of central concern are the sociomoral consequences of a standardized male beauty, set alongside the striking absence — or invisibility — of the female form within this rarified field of science. (shrink)

Interactive sonification of biomechanical quantities is gaining relevance as a motor learning aid in movement rehabilitation, as well as a monitoring tool. However, existing gaps in sonification research have prevented its widespread recognition and adoption in such applications. The incorporation of embodied principles and musical structures in sonification design has gradually become popular, particularly in applications related to human movement. In this study, we propose a general sonification model for the sit-to-stand transfer, an important activity of daily living. The model (...) contains a fixed component independent of the use-case, which represents the rising motion of the body as an ascending melody using the physical model of a flute. In addition, a flexible component concurrently sonifies STS features of clinical interest in a particular rehabilitative/monitoring situation. Here, we chose to represent shank angular jerk and movement stoppages, through perceptually salient pitch modulations and bell sounds. We outline the details of our technical implementation of the model. We evaluated the model by means of a listening test experiment with 25 healthy participants, who were asked to identify six normal and simulated impaired STS patterns from sonified versions containing various combinations of the constituent mappings of the model. Overall, we found that the participants were able to classify the patterns accurately, confidently, and in a timely manner. The amount of sonified kinematic information significantly impacted classification accuracy. The six STS patterns were also classified with significantly different accuracy depending on their kinematic characteristics. Learning effects were seen in the form of increased accuracy and confidence with repeated exposure to the sound sequences. We found no significant accuracy differences based on the participants' level of music training. Overall, we see our model as a concrete conceptual and technical starting point for STS sonification design catering to rehabilitative and clinical monitoring applications. (shrink)

What is the relationship between evolutionary contingency and diversity? The evolutionary contingency thesis emphasizes dependency relations and chance as the hallmarks of evolution. While contingency can be destructive of, for example, the fragile and complex dynamics in an ecosystem, I will mainly focus on the productive or causal aspect of contingency for a particular sort of diversity. There are many sorts of diversities: Gould is most famous for his diversity-to-decimation model, which includes disparate body plans distinguishing different phyla. However, structural (...) diversity construed more broadly spans scales, such as organization in and among cells, structural arrangements and biomechanics on various scales, and even the profile of ancestor-descendent relationships or community structure of interactions within ecosystems. By focusing on stochastic processes in contingent evolution, I argue that contingency causes structural diversity. Specifically, I focus on the plurality of structural types of cells, genetic codes, and phyla diversity as case studies. (shrink)

This ground-breaking book brings together researchers from a wide range of disciplines to discuss the control and coordination of processes involved in perceptually guided actions. The research area of motor control has become an increasingly multidisciplinary undertaking. Understanding the acquisition and performance of voluntary movements in biological and artificial systems requires the integration of knowledge from a variety of disciplines from neurophysiology to biomechanics.

A common reductionist assumption is that macro-scale behaviors can be described "bottom-up" if only sufficient details about lower-scale processes are available. The view that an "ideal" or "fundamental" physics would be sufficient to explain all macro-scale phenomena has been met with criticism from philosophers of biology. Specifically, scholars have pointed to the impossibility of deducing biological explanations from physical ones, and to the irreducible nature of distinctively biological processes such as gene regulation and evolution. This paper takes a step back (...) in asking whether bottom-up modeling is feasible even when modeling simple physical systems across scales. By comparing examples of multi-scale modeling in physics and biology, we argue that the “tyranny of scales” problem presents a challenge to reductive explanations in both physics and biology. The problem refers to the scale-dependency of physical and biological behaviors that forces researchers to combine different models relying on different scale-specific mathematical strategies and boundary conditions. Analyzing the ways in which different models are combined in multi-scale modeling also has implications for the relation between physics and biology. Contrary to the assumption that physical science approaches provide reductive explanations in biology, we exemplify how inputs from physics often reveal the importance of macro-scale models and explanations. We illustrate this through an examination of the role of biomechanics modeling in developmental biology. In such contexts, the relation between models at different scales and from different disciplines is neither reductive nor completely autonomous, but interdependent. (shrink)

Cells and tissue within injured organs undergo a complicated healing process that still remains poorly understood. Interestingly, smaller organisms respond to injury with tissue regeneration and restoration of function, while humans and other large organisms respond to injury by forming dysfunctional, fibrotic scar tissue. Over the past few decades, allometric scaling principles have been well established to show that larger organisms experience exponentially higher tissue forces during movement and locomotion and throughout the organism's lifespan. How these evolutionary adaptations may affect (...) tissue injury has not been thoroughly investigated in humans. We discuss how these adapations may affect healing and demonstrate that blocking the most evolutionary conserved biologic force sensor enables large organisms to heal after injury with true tissue regeneration. Future strategies to disrupt tissue force sensors may unlock the key to regenerating after injury in a wide range of organ systems. (shrink)

This book represents an effort to understand very old questions about biological form, function, and the relationships between them. The essays collected here reflect the diversity of approaches in evolutionary developmental biology, including not only studies by prominent scientists whose research focuses on topics concerned with evolution and development, but also historically and conceptually oriented studies that place the scientific work within a larger framework and ask how it can be pushed further. Topics under discussion range from the use of (...) theoretical and empirical biomechanics to understand the evolution of plant form, to detailed studies of the evolution of development and the role of developmental constraints on phenotypic variation. The result is a rich and interdisciplinary volume that will begin a wider conversation about the shape of Evo Devo as it matures as a field. (shrink)

Are sports really supposed to be so competitive that, as Henry R. Sanders once famously said, â oeMen, I'll be honest. Winning isâ ]the only thing!â? (WK 2012) This competitive view of sports can be contrasted with a critical view by William Shakespeare, who wrote in Othello (Act. iv. Sc. 1), â oeThey laugh that win.â (BART 2012) Contrary to these opposing views (and other ones, as will be discussed in the book), sports (in relation to both training and winning) (...) are neither possible (or impossible) nor desirable (or undesirable) to the extent that the respective ideologues (on different sides) would like us to believe. Of course, this reexamination of the opposing views on the value of sports does not mean that sports are unimportant, or that those interdisciplinary fields related to sports, like sports nutrition, physiology, psychology, biomechanics, sports philosophy, sports technology, anthropometry, kinanthropometry, and so on, are not worth studying. Needless to say, neither of these extreme views is reasonable. Instead, this book offers an alternative way to understand the future of sports, especially in the dialectic context of training and winning - while learning from different approaches in the literature but without favoring any one of them (nor integrating them, since they are not necessarily compatible with each other). More specifically, this book offers a new theory (that is, the modificative theory of sports) in order to go beyond the existing approaches in a novel way. To understand this, the book is organized in four chapters. This seminal project will fundamentally change the way that we think about sports in relation to training and winning from the combined perspectives of the mind, nature, society, and culture, with enormous implications for the human future and its â oepost-humanâ fate. (shrink)

BackgroundGait Analysis of healthy people, imitating pathological conditions while walking, has increased our understanding of biomechanical factors. The influence of the pelvis as a biomechanical constraint during gait is not specifically studied. How could mimicking a pelvic attitude influence the dynamic mechanical interaction of the body segments? We proposed an investigation of the pelvic attitude role on the gait pattern of typically developed people when they mimicked pelvic anteversion and posteroversion.Materials and methodsSeventeen healthy volunteers were enrolled in this study. They (...) simulated a pelvic anteversion and posteroversion during walking, exaggerating these postures as much as possible. 3D gait analysis was conducted using an optoelectronic system with eight cameras and two force plates. The kinematic, kinetic, and spatio-temporal parameters were compared between the three walking conditions.ResultsIn Pelvic Anteversion gait we found: increased hip flexion, increased knee flexion during stance, and reduction of ankle flexion-extension Range of Motion compared with Pelvic Normal gait. In Pelvic Posteroversion gait compared with PN, we found: decreased hip flexion-extension RoM with a tendency to hip extension, decreased knee maximum extension in stance, and increased ankle maximum dorsiflexion in stance.ConclusionThe configuration of PA contains gait similarities and differences when compared with pathologic gait where there is an anteversion as seen in children with Cerebral Palsy or Duchenne Muscular Dystrophy. Similarly, attitudes of PP have been described in patients with Charcot-Marie-Tooth Syndrome or patients who have undergone Pelvic Osteotomy. Understanding the dynamic biomechanical constraints is essential to the assessment of pathological behavior. The central nervous system adapts motor behavior in interaction with body constraints and available resources. (shrink)

This commentary cites several findings of neuromuscular research that are consistent with aspects of Plamondon's kinematic theory. In addition, we point out certain biomechanical properties of the limb that influence the requirements for the production of accurate movement, and might thus compromise the global applicability of any law governing speed/accuracy trade-offs.

Thoroughly revised for its Second Edition, Foundations for Osteopathic Medicine is the only comprehensive, current osteopathic text. It provides broad, multidisciplinary coverage of osteopathic considerations in the basic sciences, behavioral sciences, family practice and primary care, and the clinical specialties and demonstrates a wide variety of osteopathic manipulative methods. This edition includes new chapters on biomechanics, microbiology and infectious diseases, health promotion and maintenance, osteopathic psychiatry, emergency medicine, neuromusculoskeletal medicine, rehabilitation, sports medicine, progressive inhibition of neuromuscular structures, visceral manipulation, (...) A.T. Still osteopathic methods, treatment of acutely ill hospital patients, somatic dysfunction, clinical research and trials, outcomes research, and biobehavioral interactions with disease and health. Compatibility: BlackBerry(R) OS 4.1 or Higher / iPhone/iPod Touch 2.0 or Higher /Palm OS 3.5 or higher / Palm Pre Classic / Symbian S60, 3rd edition (Nokia) / Windows Mobile(TM) Pocket PC (all versions) / Windows Mobile Smartphone / Windows 98SE/2000/ME/XP/Vista/Tablet PC. (shrink)

Individuals regaining reliable day-to-day walking function after incomplete spinal cord injury report persisting unsteadiness when confronted with walking challenges. However, quantifiable measures of walking capacity lack the sensitivity to reveal underlying impairments of supra-spinal locomotor control. This study investigates the relationship between intramuscular coherence and corticospinal dynamic balance control during a visually guided Target walking treadmill task. In thirteen individuals with iSCI and 24 controls, intramuscular coherence and cumulant densities were estimated from pairs of Tibialis anterior surface EMG recordings during (...) normal treadmill walking and a Target walking task. The approximate center of mass was calculated from pelvis markers. Spearman rank correlations were performed to evaluate the relationship between intramuscular coherence, clinical parameters, and center of mass parameters. In controls, we found that the Target walking task results in increased high-frequency intramuscular coherence, which negatively related to changes in the center of mass movement, whereas this modulation was largely reduced in individuals with iSCI. The impaired modulation of high-frequency intramuscular coherence during the Target walking task correlated with neurophysiological and functional readouts, such as motor-evoked potential amplitude and outdoor mobility score, as well as center of mass trajectory length. The Target walking effect, the difference between Target and Normal walking intramuscular coherence, was significantly higher in controls than in individuals with iSCI [F = 13.042, p < 0.001]. Intramuscular coherence obtained during challenging walking in individuals with iSCI may provide information on corticospinal gait control. The relationships between biomechanics, clinical scores, and neurophysiology suggest that intramuscular coherence assessed during challenging tasks may be meaningful for understanding impaired supra-spinal control in individuals with iSCI. (shrink)

Virtuosity in music performance is often associated with fast, precise, and efficient sound-producing movements. The generation of such highly skilled movements involves complex joint and muscle control by the central nervous system, and depends on the ability to anticipate, segment, and coarticulate motor elements, all within the biomechanical constraints of the human body. When successful, such motor skill should lead to what we characterize as fluency in musical performance. Detecting typical features of fluency could be very useful for technology-enhanced learning (...) systems, assisting and supporting students during their individual practice sessions by giving feedback and helping them to adopt sustainable movement patterns. In this study, we propose to assess fluency in musical performance as the ability to smoothly and efficiently coordinate while accurately performing slow, transitionary, and rapid movements. To this end, the movements of three cello players and three drummers at different levels of skill were recorded with an optical motion capture system, while a wireless electromyogrphy (EMG) system recorded the corresponding muscle activity from relevant landmarks. We analyze the kinematic and coarticulation characteristics of these recordings separately and then propose a combined model of fluency in musical performance predicting music sophistication. Results suggest movements from expert performers' are characterized by consistently smooth strokes and scaling of muscle phasic coactivation. The explored model of fluency as function of movement smoothness and coarticulation patterns was shown to be limited by the sample size but serves as a proof of concept. Results from this study show the potential of a technology-enhanced objective measure of fluency in musical performance, which could lead to improved practices for aspiring musicians, instructors, and researchers. (shrink)

An earlier article described the mid-twentieth century origins of the method of “paradigms” in paleobiology, as a way of making testable hypotheses about the functional morphology of extinct organisms. The present article describes the use of “paradigms” through the 1970s and, briefly, to the end of the century. After I had proposed the paradigm method to help interpret the ecological history of brachiopods, my students developed it in relation to that and other invertebrate phyla, notably in Euan Clarkson’s analysis of (...) vision in trilobites. David Raup’s computer-aided “theoretical morphology” was then combined with my functional or adaptive emphasis, in Adolf Seilacher’s tripartite “constructional morphology.” Stephen Jay Gould, who had strongly endorsed the method, later switched to criticizing the “adaptationist program” he claimed it embodied. Although the explicit use of paradigms in paleobiology had declined by the end of the century, the method was tacitly subsumed into functional morphology as “biomechanics.”. (shrink)

Two meta-analyses were conducted to examine two potential sources of spatial orientation biases in human profile drawings by brain-intact individuals. The first examined profile facing direction as function of hand used to draw. The second examined profile facing direction in relation to directional scanning biases related to reading/writing habits. Results of the first meta-analysis, based on 27 study samples with 4171 participants, showed that leftward facing of profiles (from the viewer's perspective) was significantly associated with using the right hand to (...) draw. The reading/writing direction meta-analysis, based on 10 study samples with 1552 participants, suggested a modest relationship between leftward profile facing and primary use of a left-to-right reading/writing direction. These findings suggest that biomechanical and cultural factors jointly influence hand movement preferences and in turn the direction of facing of human profile drawings. -/- . (shrink)

Objective To study how doctors care for their patients, both medically and as fellow humans, through observing their conduct in patient–doctor encounters. Design Qualitative study in which 101 videotaped consultations were observed and analysed using a Grounded Theory approach, generating explanatory categories through a hermeneutical analysis of the taped consultations. Setting A 500-bed general teaching hospital in Norway. Participants 71 doctors working in clinical non-psychiatric departments and their patients. Results The doctors were concerned about their patients' health and how their (...) medical knowledge could be of service. This medical focus often over-rode other important aspects of the consultations, especially existential elements. The doctors actively directed the focus away from their patients' existential concerns onto medical facts and rarely addressed the personal aspects of a patient's condition, treating them in a biomechanical manner. At the same time, however, the doctors attended to their patients with courteousness, displaying a polite and friendly attitude and emphasising the relationship between them. Conclusions The study suggests that the main failing of patient–doctor encounters is not a lack of courteous manners, but the moral offence patients experience when existential concerns are ignored. Improving doctors' social and communication skills cannot resolve this moral problem, which appears to be intrinsically bound to modern medical practice. Acknowledging this moral offence would, however, be the first step towards minimising the effects thereof. (shrink)

Efforts from diverse disciplines, including evolutionary studies and biomechanical experiments, have yielded new insights into the genetic, signaling, and mechanical control of tooth formation and functions. Evidence from fossils and non‐model organisms has revealed that a common set of genes underlie tooth‐forming potential of epithelia, and changes in signaling environments subsequently result in specialized dentitions, maintenance of dental stem cells, and other phenotypic adaptations. In addition to chemical signaling, tissue forces generated through epithelial contraction, differential growth, and skeletal constraints act (...) in parallel to shape the tooth throughout development. Here recent advances in understanding dental development from these studies are reviewed and important gaps that can be filled through continued application of evolutionary and biomechanical approaches are discussed. (shrink)

The scientific and practical fields—especially high-performance sports—increasingly request a stronger focus be placed on individual athletes in human movement science research. Machine learning methods have shown efficacy in this context by identifying the unique movement patterns of individuals and distinguishing their intra-individual changes over time. The objective of this investigation is to analyze biomechanically described movement patterns during the fatigue-related accumulation process within a single training session of a high number of repeated executions of a ballistic sports movement—specifically, the frontal (...) foot kick (mae-geri) in karate—in expert athletes. The two leading research questions presented for consideration are (1) Can characteristics of individual movement patterns be observed throughout the entire training session despite continuous changes, i.e., even as fatigue-related processes increase? and (2) How do intra-individual movement patterns change as fatigue-related processes increase throughout a training session? Sixteen expert karatekas performed 606 frontal foot kicks directed toward an imaginary target. The kicks were performed in nine sets at 80% (K-80) of the self-experienced maximal intensity. In addition, six kicks at maximal intensity (K-100) were performed after each of the nine sets. Between the sets, the participants took a 90-s break. Three-dimensional full-body kinematic data of all kicks were recorded with 10 infrared cameras. The normalized waveforms of nine upper- and lower-body joint angles were classified using a supervised machine learning method (support vector machine). The results of the classification revealed a disjunct distinction between the kinematic movement patterns of individual athletes. The identification of unique movement patterns of individual athletes was independent of the intensity and the degree of fatigue-related processes. In other words, even with the accumulation of fatigue-related processes, the unique movement patterns of an individual athlete can be clearly identified. During the training session, changes in intra-individual movement patterns could also be detected, indicating the occurrence of adaptations in individual movement patterns throughout the fatigue-related accumulation process. The results suggest that these adaptations can be modeled in terms of changes in patterns rather than increasing variance. Practical consequences are critically discussed. (shrink)

Plants move in very different ways and for different reasons, but some active carnivorous plants perform extraordinary motion: Their snap‐, catapult‐ and suction traps perform very fast and spectacular motions to catch their prey after receiving mechanical stimuli. Numerous investigations have led to deeper insights into the physiology and biomechanics of these trapping devices, but they are far from being fully understood. We review concisely how plant movements are classified and how they follow principles that bring together speed, actuation (...) and architecture of the moving organ. In particular, we describe and discuss how carnivorous plants manage to execute fast motion. We address open questions and assess the prospects for future studies investigating potential universal mechanisms that could be the basis of key characteristic features in plant movement such as stimulus transduction, post‐stimulatory mechanical answers, and organ formation. (shrink)

Morphogenesis is a general concept in biology including all the processes which generate tissue shapes and cellular organizations in a living organism. Many hybrid formalizations have been proposed for modelling morphogenesis in embryonic or adult animals, like gastrulation. We propose first to study the ventral furrow invagination as the initial step of gastrulation, early stage of embryogenesis. We focus on the study of the connection between the apical constriction of the ventral cells and the initiation of the invagination. For that, (...) we have created a 3D biomechanical model of the embryo of the Drosophila melanogaster based on the finite element method. Each cell is modelled by an elastic hexahedron contour and is firmly attached to its neighbouring cells. A uniform initial distribution of elastic and contractile forces is applied to cells along the model. Numerical simulations show that invagination starts at ventral curved extremities of the embryo and then propagates to the ventral medial layer. Then, this observation already made in some experiments can be attributed uniquely to the specific shape of the embryo and we provide mechanical evidence to support it. Results of the simulations of the “pill-shaped” geometry of the Drosophila melanogaster embryo are compared with those of a spherical geometry corresponding to the Xenopus lævis embryo. Eventually, we propose to study the influence of cell proliferation on the end of the process of invagination represented by the closure of the ventral furrow. (shrink)

La solución de los problemas de salud requiere de la interrelación entre diferentes ramas científicas y tecnológicas, tales como la Biomecánica, las tecnologías de la información, la ingeniería y las ciencias médicas. La importancia de la comunicación interdisciplinaria en las universidades fundamenta la creación de un grupo de investigación que fusiona el conocimiento de la mecánica clásica con las disciplinas de la salud y la participación de pacientes, técnicos, ingenieros, médicos y estudiantes. En el trabajo se realiza una reflexión sobre (...) el carácter interdisciplinario de las investigaciones, cómo se inserta la Ingeniería Mecánica desde la modelación en la solución de problemas de salud y se brindan algunos resultados obtenidos por los miembros del Grupo de Biomecánica y Bioingeniería de la Universidad "Ignacio Agramonte y Loynaz" de Camagüey. The solution of health problems require an interrelation between different scientific and technological branches, such as biomechanics, information technologies, engineering and medical sciences. The importance of the interdisciplinary communication in universities lays the base on the creation of an investigative group that fuses the knowledge of classic mechanic with the disciplines of medicine and the participation of patients, technicians, engineers, doctors and students. A reflection about the interdisciplinary character of investigations and how mechanic engineering is inserted in the model to solve health problems is carried out in this work. Some results obtained by the members of the Biomechanics and Bioengineering Group of "Ignacio Agramonte y Loynaz" University are offered. (shrink)

The aim of the experiment was to evaluate the adaptive responses of biomechanical and electromyographic parameters to vertical unloading when walking during the 4-month isolation experiment SIRIUS-19 in the ground-based space station model. The study involved 6 healthy international crew members of the SIRIUS-19 project aged 34 ± 6.2 years. Body Weight Unloading conditions was created by the h/p/cosmos airwalk system. The locomotor test included walking with a sequential change of BWU modes: 5-min walking with 0% BWU, 5-min walking with (...) 65% BWU and 5-min walking with 85% BWU. Ground Reaction Force was recorded by the h/p/cosmos treadmill device. Muscle Lab Model 4000e device was used to record the electromyographic signals of the hip and shin muscles. The locomotor test was performed twice before GBI, monthly during GBI and 1 week after leaving isolation. The results obtained before GBI demonstrate that the changes of support and proprioceptive afferentation signals play significant role in reorganizing of the biomechanical structure of motor acts and the development of new movement patterns. The results of the study are consistent with the previously obtained results of other studies in this direction. Despite the fact that during the GBI the participants of the experiment performed regular physical training, a decrease in the performance indicators values was detected, especially pronounced after 100 days of GBI. This is probably due to limited space of a space station model, as well as the development of a special motor stereotype in it. Noteworthy are the results obtained after the 4th session of the experiment, indicating the effect of sensorimotor learning. We think that the data obtained in this study will be useful in research both in gravitational physiology and in clinical medicine. (shrink)

The Frame/Content theory deals with how and why the first language evolved the present-day speech mode of programming syllable “Frame” structures with segmental “Content” elements. The first words are considered, for biomechanical reasons, to have had the simple syllable frame structures of pre-speech babbling, and were perhaps parental terms, generated within the parent–infant dyad. Although all gestural origins theories have iconicity as a plausible alternative hypothesis for the origin of the meaning-signal link for words, they all share the problems of (...) how and why a fully fledged sign language, necessarily involving a structured phonology, changed to a spoken language. (shrink)

Vision is known to improve human postural responses to external perturbations. This study investigates the role of vision for the responses to continuous pseudorandom support surface translations in the body sagittal plane in three visual conditions: with the eyes closed, in stroboscopic illumination and with eyes open in continuous illumination with the room as static visual scene. In the frequency spectrum of the translation stimulus we distinguished on the basis of the response patterns between a low-frequency, mid-frequency, and high-frequency range. (...) With EC, subjects’ mean sway response gain was very low in the LFR. On average it increased with EO/SI and more so with EO/CI. In contrast, the average gain in the MFR decreased from EC to EO/SI and further to EO/CI. In the HFR, all three visual conditions produced, similarly, high gain levels. A single inverted pendulum model controlling center of mass balancing about the ankle joints formally described the EC response as being strongly shaped by a resonance phenomenon arising primarily from the control’s proprioceptive feedback loop. The effect of adding visual information in these simulations lies in a reduction of the resonance, similar as in the experiments. Extending the model to a double inverted pendulum suggested in addition a biomechanical damping effective from trunk sway in the hip joints on the resonance. (shrink)

What is the epistemological status of a world within which speaking to trees would appear as an appropriate behavior? It would be a world perceived as a community of autonomous beings worthy of respect. Such a world contrasts with the anthropocentric conception of the world as a value?free reservoir of raw materials, but neither worldview can or should claim descriptive accuracy. Both are equally ?manners of speaking? and the choice between them must rest on whether they are conducive to ecologically (...) constructive or ecologically destructive behavior. On that basis, speaking to trees is a legitimate, speaking of biomechanisms an illegitimate form of verbal behavior. (shrink)

Considering the most recent advances in artificial intelligence and biomechanics, a hypothetical future of physicalism is explored. It is concluded that a rational and sensible extrapolation of present and expected future advances in those two areas will have vast consequences in the physicalist view. In particular, it is also argued that consciousness cannot be defined in a simple general manner, but only understood through the observable and behavioural actions of humans or sufficiently advanced robots, which may be, at some (...) future time, indistinct. This last result is established by applying what we call Plato’s trap, and our main conclusion is a defence of physicalism. It is argued that human beings are robots which soon will be indistinguishable from suitable advanced man-made robots, which will in turn render many philosophical questions and objections to physicalism irrelevant and, in fact, quite similar in sense and importance to some philosophical medieval questions about God, the soul and immortality. (shrink)

The study of human origins is a kaleidoscopic field, a multitude of objects, reflections, and disciplines a swirl in an ever-changing tumult. The extreme diversity of the elements of information that are indispensable to this field of study (teeth, bones, apes, genes, ancient objects, present-day objects, biomechanical factors, cultural constructions …) appears all by itself to be enough to consign any attempt at synthesis to the realm of the Utopian. It hardly seems reasonable to expect the disparate sciences that fuel (...) the field (paleoanthropology, archaeology, molecular biology, physics, psychology, and others) and the contradictory conceptions of scientific activity that they defend (human sciences, natural sciences, experimental sciences, exact sciences) to be joined with any regularity. As for formulating an overall problematics of the interdependent phenomena encountered in the field, one would have to be more than optimistic to entertain such dreams. And yet this is exactly the program that prehistory and paleoanthropology are laboring to construct tinder the label “the study of the origins of man,” an expression that includes both diachronic processes (human evolution) and activities or behaviors from particular moments, elements that are exceedingly difficult to compare given the separation of their geographic and temporal contexts. (shrink)

The jaw mechanism of cichlid fishes is an intricate apparatus with complex force transmission from muscles to environment. The proportions of this apparatus change considerably during growth mainly due to scale effects. In adult fishes, the proportions differ, corresponding with the type of preferred food. In such a complex mechanism, it is very hard to gain insight into the functional meaning of the differences in proportions, unless a biomechanical model is constructed, describing kinematics and force equilibria of the apparatus.Such a (...) model has been constructed and by means of perturbation analysis anatomical points could be selected of which the positions are very important for the function of biting. These hot spots need only small displacements in order to obtain an increase in biting force. By means of a newly developed mathematical technique, it was possible to move the anatomical points in very small steps towards more favourable positions for the function of biting. (shrink)

There is a growing demand for information and computational technology for surgeons help with surgical planning as well as prosthetics design. The two-dimensional images are registered to the three-dimensional (3D) model for high efficiency. To reconstruct the 3D model of knee joint including bone structure and main soft tissue structure, the evaluation and analysis of sports injury and rehabilitation treatment are detailed in this study. Mimics 10.0 was used to reconstruct the bone structure, ligament, and meniscus according to the pulse (...) diffusion-weighted imaging sequence (PDWI) and stir sequences of magnetic resonance imaging (MRI). Excluding congenital malformations and diseases of the skeletal muscle system, MRI scanning was performed on bilateral knee joints. Proton weighted sequence (PDWI sequence) and stir pulse sequence were selected for MRI. The models were imported into Geomagic Studio 11 software for refinement and modification, and 3D registration of bone structure and main soft tissue structure was performed to construct a digital model of knee joint bone structure and accessory cartilage and ligament structure. The 3D knee joint model including bone, meniscus, and collateral ligament was established. Reconstruction and image registration based on mimics and Geomagic Studio can build a 3D model of knee joint with satisfactory morphology, which can meet the requirements of teaching, motion simulation, and biomechanical analysis. (shrink)