Explore chapters and articles related to this topic
The Microcirculation Physiome
Published in Joseph D. Bronzino, Donald R. Peterson, Biomedical Engineering Fundamentals, 2019
Aleksander S. Popel and Roland N. Pittman
e microcirculation comprises blood vessels (arterioles, capillaries, and venules) with diameters less than approximately 150 μm. e importance of the microcirculation is underscored by the fact that most of the hydrodynamic resistance of the circulatory system lies in the microvessels (especially in arterioles) and most of the exchange of nutrients and waste products occurs at the level of the smallest microvessels. e subjects of microcirculatory research are blood ow and molecular transport in microvessels, mechanical interactions and molecular exchange between these vessels and the surrounding tissue, and regulation of blood ow, pressure, and molecular transport [43]. is review focuses on quantitative aspects of microvascular research; thus, we frame it in terms of the microcirculation physiome, the quantitative and integrated description of physiological processes that involve the microcirculation in an animal or human, across multiple scales. To achieve a quantitative understanding of the complexity of these processes as well as understanding the relationships between the structure and functional behavior, it is necessary to build experiment-based mathematical and computational models. In addition to describing key experimental ndings in the eld, we will also review major accomplishments in mathematical and computational modeling and simulations. e experimental and theoretical information on the microcirculation can be organized in the form of databases encompassing anatomical, biophysical, and functional data; gene regulation; signaling and metabolic networks; regulation and
Towards rapid prediction of personalised muscle mechanics: integration with diffusion tensor imaging
Published in Computer Methods in Biomechanics and Biomedical Engineering: Imaging & Visualization, 2020
Justin Fernandez, Kumar Mithraratne, Massoud Alipour, Geoffrey Handsfield, Thor Besier, Ju Zhang
The 3D FE geometrical model, and fitted DTI fibre field, were modelled using high-order cubic Hermite basis functions (Fernandez et al. 2004). Models were fitted with a geometric error of less than 3-mm RMS. Cubic Hermite elements differ from the usual Lagrange family FEs in that they preserve both the continuity of the nodal values (C0 continuity), and their first derivatives (C1 continuity). This provides many advantages in constructing FE geometry, particularly of biological structures such as muscles and other organs that typically have smooth surfaces and fewer numbers of elements are required. The human gastrocnemius muscle (medial and lateral heads) presented here also forms part of a suite of musculoskeletal data within the International Union of Physiological Sciences (IUPS) Physiome Project repository (Hunter et al. 2005), which is a framework for creation, sharing and dissemination of mathematical models of human physiology. Full details on cubic Hermite interpolation and the techniques used to fit the geometric models have been previously reported in detail (Fernandez et al. 2004).