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Combining published literature, radiographic imaging, and medical illustration, this study aimed to develop an anatomically accurate 3-dimensional (3D) digital model of the human tongue, and to make this model publicly available for education and training purposes. The intrinsic and extrinsic muscles of the tongue were manually segmented from a head and neck CT angiogram of a healthy 29-year-old female. Data derived from published anatomical studies were compiled to provide additional anatomical detail to each tongue muscle. These anatomical details were then incorporated into a model by a 3D medical illustrator. A total of nine muscles were segmented for this study, along with the mandible and the hyoid bone. 3D meshes of the extrinsic muscles of the tongue, intrinsic muscles of the tongue, and the mylohyoid were created from CT angiography segmentation data. These meshes were refined in digital 3D space based off data from peer-reviewed anatomical studies. The final model was then uploaded to a publicly available 3D model repository. The tongue is a complex 3D organ with important roles in swallowing, speaking, and airway protection. By combining radiographic data with published anatomical descriptions, and through the collaboration between neuroradiology, head and neck surgery, and medical illustration, we developed an anatomically accurate, detailed 3D model of the oral tongue, which may serve as a powerful anatomy teaching aid. [ABSTRACT FROM AUTHOR]

A major focus of current biological studies is to fill the knowledge gaps between cell, tissue and organism scales. To this end, a wide array of contemporary optical analytical tools enable multiparameter quantitative imaging of live and fixed cells, three-dimensional (3D) systems, tissues, organs and organisms in the context of their complex spatiotemporalbiological and molecular features. In particular, the modalities of luminescence lifetime imaging, comprising fluorescence lifetime imaging (FLI) and phosphorescence lifetime imaging microscopy (PLIM), in synergy with Förster resonance energy transfer (FRET) assays, provide a wealth of information. On the application side, the luminescence lifetime of endogenous molecules inside cells and tissues, overexpressed fluorescent protein fusion biosensor constructs or probes delivered externally provide molecular insights at multiple scales into protein-protein interaction networks, cellular metabolism, dynamics of molecular oxygen and hypoxia, physiologically important ions, and other physical and physiological parameters. Luminescence lifetime imaging offers a unique window into the physiological and structural environment of cells and tissues, enabling a new level of functional and molecular analysis in addition to providing 3D spatially resolved and longitudinal measurements that can range from microscopic to macroscopic scale. We provide an overview of luminescence lifetime imaging and summarize key biological applications from cells and tissues to organisms. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to provide a solution for natural convection in a cavity with a partial heater in case of volumetric heating and analysis of the entropy generation.Design/methodology/approach The control volume method based on three-dimensional (3D) vorticity-potential vector was applied to solve governing equations of natural convection in a 3D cavity with a fin for different governing parameters as external Rayleigh numbers (103=RaE=106), internal Rayleigh numbers 103=RaI=106, partition height (0.25=h=0.75) and partition location (0.25=c=0.75). A code was written by using Fortran platform.Findings The edge of the fin becomes important on entropy generation. The ratio of the RaI/RaE plays the important role on natural convection and entropy generation. The variation of external Rayleigh number becomes insignificant for the RaI/RaE>1.Originality/value The originality of this work is to analyze the entropy generation and natural convection in a cubical cavity with volumetrically heating. [ABSTRACT FROM AUTHOR]

Purpose -- The main purpose of this paper is to conduct on three-dimensional buoyancy and thermocapillary convection in an enclosure. Entropy generation is obtained from the calculated values of velocities and temperatures. Design/methodology/approach -- As numerical method, the vorticity-vector potential formalism allows, in a three-dimensional configuration, the elimination of the pressure, which is a delicate term to treat. The control volume finite difference method is used to discretize equations. The central-difference scheme for treating convective terms and the fully implicit procedure to discretize the temporal derivatives are retained. The grid is uniform in all directions with additional nodes on boundaries. The successive relaxation iterating scheme is used to solve the resulting non-linear algebraic equations. Findings -- Results are presented via entropy generation due to heat transfer, entropy generation due to fluid friction and total entropy generation. It is found that Marangoni number becomes more effective parameter on total entropy generation for lower values of Rayleigh numbers. Practical implications -- In any thermal system under buoyancy induced and thermocapillary flow. Originality/value -- It is believed that this is the first paper on three-dimensional solution of entropy generation in a cubical cavity under thermocapillary buoyancy flow. [ABSTRACT FROM AUTHOR]

Abstract: A finite deformation micromorphic materially linear isotropic elastic model is formulated and implemented for three dimensional finite element analysis. The model is based on the kinematics, balance equations and thermodynamic equations proposed by . The constitutive equations are calculated in the reference configuration, and the resulting stresses are mapped to the current configuration. The balance of linear momentum and the balance of first moment of momentum are linearized to construct the consistent tangent for three dimensional finite element implementation for solution by the Newton–Raphson method. Three dimensional numerical examples are analyzed to demonstrate preliminarily the implementation. [Copyright &y& Elsevier]

Abstract: Mathematical modelling is used to study the evolution of damage caused by indentation loading on curved bilayers consisting of brittle shells filled with polymer support material. Such loads are pertinent to all-ceramic crown structures on tooth dentin in occlusal function. The aim is to develop tools to assist in the design of such structures to ensure both high damage resistance and high damage tolerance. Specifically, the initiation and propagation of a radial crack emanating from the interface is studied using the boundary element method (BEM) in three dimensions. The system that is analysed consists of a spherical indenter and both flat and convex bi-material samples. A semi-circular intrinsic flaw/crack is assumed to lie on the axis of indentation at the interface of the two materials, in the coating. Upon application of an indentation load, the mode I stress intensity factor distribution along the crack front is determined and the crack front is propagated using a small increment. By repeating this process, the critical load for propagation of the crack is obtained as a function of crack size. The results compare well with experimental crack propagation studies in bi-materials, as well as observed damage in porcelain crowns that have been used to repair teeth. The convex models show that radial cracks can exist in the brittle coating, without leading to catastrophic failure, up to a critical crack length. An increase in the applied load, causing the crack to grow beyond this length, causes the coating to fail in an unstable way. The results show that there is an optimum combination of design parameters for maximising the damage resistance. It is shown that larger convex radii of curvature lead to higher damage tolerance. [Copyright &y& Elsevier]

A three-dimensional transient, combined model (headspace model + soil model + conduction model in bulk grain) was developed to predict grain temperatures in a granary. Different meshes (mesh refinement in the whole domain or at the boundary) including linear and hybrid (linear and quadratic) elements were used to simulate grain temperatures. Prediction accuracies of temperatures produced by the different meshes were compared, and the model was validated using measured temperatures in two flat bottom bins (3.76 m diameter and 5.5 m high filled with wheat up to 3 m) located side by side in the north-south orientation near Winnipeg, Manitoba. Grain temperatures predicted by the model were in close agreement with the measured temperatures throughout a 21-month test in the two bins. By using a hybrid element mesh (mesh refinement at the boundary), the mean, standard error, and maximum of the absolute difference between the measured and predicted temperatures in the south bin were 2.2°C, 0.4°C, and 7.0°C, respectively. The mean, standard error, and maximum of the absolute difference predicted by a linear element model (88 linear elements each layer) in the south bin were 2.1°C, 0.3°C, and 6.3°C, respectively. Including a headspace model improved the prediction accuracy of the conduction model at the top of the grain bulk. Mesh refinement only at the boundary produced a homogeneous distribution of errors in the whole domain; however, mesh refinement in the whole domain gave higher errors at the walls than at the center of the bins. Considering the increased computer time and slightly improved accuracy by mesh refinement at the boundary, a uniform mesh with mesh refinement in the whole domain was preferable for predicting grain temperatures in an entire grain bin. [ABSTRACT FROM AUTHOR]