Download or read book Brain Biomechanics microform Dynamical Morphology and Non linear Viscoelastic Models of Hydrocephalus written by Corina S. Drapaca and published by National Library of Canada = Bibliothèque nationale du Canada. This book was released on 2002 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biomechanics of the Brain written by Karol Miller and published by Springer. This book was released on 2019-08-08 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new edition presents an authoritative account of the current state of brain biomechanics research for engineers, scientists and medical professionals. Since the first edition in 2011, this topic has unquestionably entered into the mainstream of biomechanical research. The book brings together leading scientists in the diverse fields of anatomy, neuroimaging, image-guided neurosurgery, brain injury, solid and fluid mechanics, mathematical modelling and computer simulation to paint an inclusive picture of the rapidly evolving field. Covering topics from brain anatomy and imaging to sophisticated methods of modeling brain injury and neurosurgery (including the most recent applications of biomechanics to treat epilepsy), to the cutting edge methods in analyzing cerebrospinal fluid and blood flow, this book is the comprehensive reference in the field. Experienced researchers as well as students will find this book useful.
Download or read book Biomechanics of the Cerebrum at Finite Strain written by Thibault Philippe Prévost and published by . This book was released on 2010 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present study addresses the large strain nonlinear mechanical response of the cerebral cortex at the macroscopic tissue level and at the microscopic cell level. Unconfined uniaxial compression tests were conducted in vitro on cortical samples of porcine brains. The tests consisted of load-unload and relaxation segments to 50% nominal deformation at 0.01 to 10 s-1 strain rates. The tissue exhibited moderate volumetric compressibility, marked hysteretic features, and substantial nonlinearities. Indentation tests - with displacement histories mirroring those imposed in compression - were performed on the cortex of porcine brains in vivo, in situ and in vitro, in order to assess and contrast the mechanical properties of the live and dead tissue. The tissue response shared similar qualitative nonlinear viscoelastic features under all testing conditions, although, quantitatively, the response was found to be significantly stiffer in situ than in vivo. Test protocols were also developed at the neuronal cell level using atomic force microscopy. The response of individual somata to cyclic load-unload and relaxation test sequences was found to be nonlinear with time dependencies and hysteretic patterns similar to those measured at the tissue level. A large strain kinematics nonlinear continuum model was proposed to capture the features of the tissue and cell responses. The model was numerically implemented into a three-dimensional finite-element framework. The continuum formulation was found to successfully account for the main experimental observations gathered in vitro at the tissue and cell levels. The present study provides novel insights into the tissue rheology in vivo, in situ and in vitro, at large strains, in the quasi-static and dynamic strain rate regime and reports the first body of observations on the large strain nonlinear viscoelastic properties of brain tissue in vivo. These observations could be directly compared to those pertaining to the tissue response in situ and in vitro, thereby providing a unique quantitative basis for further refinements of existing biomechanical models relying only on in vitro/situ measurements. The consistent set of mechanical data collected, and the constitutive framework proposed at the tissue and cell levels might support the development of multiscale numerical models to study traumatic brain injury.
Download or read book Numerical Study of a Viscoelastic Model for Hydrocephalus written by Jenny Hei Man Lee and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nonlinear Viscoelastic Wave Propagation in Brain Tissue written by Kaveh Laksari and published by . This book was released on 2013 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: A combination of theoretical, numerical, and experimental methods were utilized to determine that shock waves can form in brain tissue from smooth boundary conditions. The conditions that lead to the formation of shock waves were determined. The implication of this finding was that the high gradients of stress and strain that could occur at the shock wave front could contribute to mechanism of brain injury in blast loading conditions. The approach consisted of three major steps. In the first step, a viscoelastic constitutive model of bovine brain tissue under finite step-and-hold uniaxial compression with 10 1/s ramp rate and 20 s hold time has been developed. The assumption of quasi-linear viscoelasticity (QLV) was validated for strain levels of up to 35%. A generalized Rivlin model was used for the isochoric part of the deformation and it was shown that at least three terms (C_10, C_01 and C_11) are needed to accurately capture the material behavior. Furthermore, for the volumetric deformation, a linear bulk modulus model was used and the extent of material incompressibility was studied. The hyperelastic material parameters were determined through extracting and fitting to two isochronous curves (0.06 s and 14 s) approximating the instantaneous and steady-state elastic responses. Viscoelastic relaxation was characterized at five decay rates (100, 10, 1, 0.1, 0 1/s) and the results in compression and their extrapolation to tension were compared against previous models. In the next step, a framework for understanding the propagation of stress waves in brain tissue under blast loading was developed. It was shown that tissue nonlinearity and rate dependence are key parameters in predicting the mechanical behavior under such loadings, as they determine whether traveling waves could become steeper and eventually evolve into shock discontinuities. To investigate this phenomenon, the QLV material model developed based on finite compression results mentioned above was extended to blast loading rates, by utilizing the stress data published on finite torsion of brain tissue at high rates (up to 700 1/s). It was shown that development of shock waves is possible inside the head in response to compressive pressure waves from blast explosions. Furthermore, it was argued that injury to the nervous tissue at the microstructural level could be attributed to the high stress and strain gradients with high temporal rates generated at the shock front and this was proposed as a mechanism of injury in brain tissue. In the final step, the phenomenon of shock wave formation and propagation in brain tissue was further studied by developing a one-dimensional model of brain tissue using the Discontinuous Galerkin finite element method. This model is capable of capturing high-gradient waves with higher accuracy than commercial finite element software. The deformation of brain tissue was investigated under displacement input and pressure input boundary conditions relevant to blast over-pressure reported in the literature. It was shown that a continuous wave can become a shock wave as it propagates in the tissue when the initial changes in acceleration are beyond a certain limit. The high spatial gradients of stress and strain at the shock front cause large relative motions at the cellular scale at high temporal rates even when the maximum strains and stresses are relatively low. This gradient-induced local deformation occurs away from the boundary and can therefore contribute to the diffuse nature of blast-induced injuries.
Download or read book Biomechanics of the Brain written by Raelene J. Driscoll and published by . This book was released on 1995 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Non invasive Evaluation of Human Brain Fluid Dynamics and Skull Biomechanics in Relation to Cognitive Functioning written by I︠U︡riĭ Evgenʹevich Moskalenko and published by . This book was released on 2009 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent research of the Beckley Foundation with Prof. Yuri Moskalenko, world-recognized pioneer in cerebral circulation, has revealed that the loss of the elastic quality of the skull due to normal bone ossification processes results in a decrease of 8-10% in the supply of blood to the brain, due to the inability of the cranium to accept the full volume of each heartbeat. Considering that the heart beats at least 60 times a minute this loss of up to 2 ml per pulse stroke is significant, and our study is revealing that over the life span this loss may have an impact on the individual's mental functioning and thus on society as a whole. This new information is derived from a rapidly evolving concept which makes possible the evaluation of cerebral circulation on the basis of the constantly changing pressure/volume interaction between the structural and fluid components of the brain system. The
Download or read book Spinal Imaging written by Johan W.M. van Goethem and published by Springer Science & Business Media. This book was released on 2007-12-27 with total page 591 pages. Available in PDF, EPUB and Kindle. Book excerpt: - Comprehensive, up-to-date textbook on the imaging of frequently encountered spinal disorders - Richly illustrated - All imaging modalities considered, e.g. plain film, multidetector CT and MRI - Designed to ensure ease of use, with a logical structure and extensive index
Download or read book Handbook of Orthodontics for the Student and General Practitioner written by Robert E. Moyers and published by . This book was released on 1973 with total page 800 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dictionary of Medical Acronyms and Abbreviations written by Stanley Jablonski and published by Hanley & Belfus. This book was released on 2004-09 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dictionary lists acronyms and abbreviations occurring with a reasonable frequency in the literature of medicine and the health care professions. Abbreviations and acronyms are given in capital letters, with no punctuation, and with concise definitions. The beginning sections also include symbols, genetic symbols, and the Greek alphabet and symbols.
Download or read book Fundamentals of Biomedical Engineering written by Sawhney and published by New Age International Limited Publishers. This book was released on 2007-12 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: About the Book: A well set out textbook explains the fundamentals of biomedical engineering in the areas of biomechanics, biofluid flow, biomaterials, bioinstrumentation and use of computing in biomedical engineering. All these subjects form a basic part of an engineer's education. The text is admirably suited to meet the needs of the students of mechanical engineering, opting for the elective of Biomedical Engineering. Coverage of bioinstrumentation, biomaterials and computing for biomedical engineers can meet the needs of the students of Electronic & Communication, Electronic & Instrumentat.
Download or read book Alphaherpesviruses written by Sandra Knowles Weller and published by Caister Academic Press Limited. This book was released on 2011 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Alphaherpesviruses are a fascinating group of DNA viruses that includes important human pathogens such as herpes simplex virus type 1 (HSV-1), HSV-2, and varicella-zoster virus (VZV): the causative agents of cold sores, genital ulcerous disease, and chickenpox/shingles, respectively. A key attribute of these viruses is their ability to establish lifelong latent infection in the peripheral nervous system of the host. Such persistence requires subversion of the host's immune system and intrinsic antiviral defense mechanisms. Understanding the mechanisms of the immune evasion and what triggers viral reactivation is a major challenge for today's researchers. This has prompted enormous research efforts into understanding the molecular and cellular biology of these viruses. This up-to-date and comprehensive volume aims to distill the most important research in this area providing a timely overview of the field. Topics covered include: transcriptional regulation, DNA replication, translational control, virus entry and capsid assembly, the role of microRNAs in infection and oncolytic vectors for cancer therapy. In addition there is coverage of virus-host interactions, including apoptosis, subversion of host protein quality control and DNA damage response pathways, autophagy, establishment and reactivation from latency, interferon responses, immunity and vaccine development. Essential reading for everyone working with alphaherpesviruses and of interest to all virologists working on latent infections.
Download or read book Type Typo written by and published by Omair Nazir. This book was released on with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Yvain written by Chretien de Troyes and published by Yale University Press. This book was released on 1987-09-10 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: A twelfth-century poem by the creator of the Arthurian romance describes the courageous exploits and triumphs of a brave lord who tries to win back his deserted wife's love
Download or read book Antifascisms written by David Ward and published by Fairleigh Dickinson Univ Press. This book was released on 1996 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an in-depth analysis of three of the most crucial years in twentieth-century Italian history, the years 1943-46. After more than two decades of a Fascist regime and a disastrous war experience during which Italy changed sides, these years saw the laying of the political and cultural foundations for what has since become known as Italy's First Republic. Drawing on texts from the literature, film, journalism, and political debate of the period, Antifascisms offers a thorough survey of the personalities and positions that informed the decisions taken in this crucial phase of modern Italian history.
Download or read book Sisters Super Creeps and Slushy Gushy Love Songs written by Karen McCombie and published by . This book was released on 2011 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ally knows her super-efficient big sis Linn finds their chaotic family a bit ... exasperating. But when Linn falls for Q, the tearaway lead singer in a local band, all her sensible ways go out of the window. Everyone else can see that Q's a creep, but does Ally have the courage to burst Linn's heart-shaped bubble?
