We propose to estimate rule-based myocardial fiber model (RBM) parameters from DT-MRI, with the goal of personalizing the fiber architecture for cardiac simulations. The RBM is based on a space-dependent angle distribution on the heart surface and then extended to the whole domain through an harmonic lifting of the fiber vectors. For the angles estimation we use a static Unscented Kalman Filter...

Cardiac ultrasound plays an important role in the imaging of hearts in basic cardiovascular research and clinical examinations. 3D ultrasound imaging can provide the geometry or motion information of the heart. Especially, the wrapping of cardiac fiber orientations to the ultrasound volume could supply useful information on the stress distributions and electric action spreading. However, how to...

Disordered fiber mats made of glass microfibers (GMF) were studied using small-angle light scattering (SALS), ultrasmall-angle X-ray scattering (USAXS), SEM, and optical microscopy. The morphological scaling of these materials in the micron scale was very similar to that of polymers in the nanometer scale. In some fiber mats, such as GMF, the structure is randomized at the time of formation, le...

A novel fiber-optic bending sensor based upon the propagation of LP21 mode is demonstrated. The sensor, comprised of an S-bend fiber on an elastic film, measures LP21 mode specklegram rotation, which increments linearly with bending angle by the stress-optic effect. The sensor is capable of experimentally achieving a sensitivity as high as 4.13 rad/m(-1). The theoretical analysis of the sensor,...

In the segmented axial musculature of fishes and amphibians, the patterns of muscle fiber shortening depend on both the orientation of muscle fibers relative to the long axis of the body as well as the distance of fibers from the neutral axis of bending (vertebral column). In this study we use the relatively simple architecture of salamander hypaxial muscles to explore the separate and combined...

Introduction: We present a model of simulation of diffusion in white matter. This model has been used in Diffusion Weighted Imaging researches as a tool for employing cylindrically constrained two-tensor models to identify two independent directions within a voxel and assessing the orientation angle as a parameter that influence on fractional anisotropy.   Materials a...

The splitting and the shift of resonance peaks in the output spectrum of two-mode fiber acousto-optic devices caused by twist perturbation are described. An elliptical-core two-mode fiber and a two-mode photonic-crystal fiber are used for the analysis. The splitting of the resonance peaks are found to be almost linearly proportional to the twist angle of the fiber with the slopes of about 0.58 ...

This study proposes a genetic algorithm (GA)-based optimization method for fiber orientation angle and examines its effectivity. Determining the optimal involves searching solution from multitudinous combinations, which makes it difficult to attain by simple GA. In addition, generally used principal stress design cannot give an when combined loads are applied. Therefore, is developed that does ...

This review provides a formalism for understanding magic angle effects in clinical studies. It involves consideration of the fiber-to-field angle for linear structures such as tendons, ligaments, and peripheral nerves, disc-like and circular structures such as menisci and labra, as well as complex three-dimensional structures. There may be one or more fiber types with different orientations wit...

Introduction: Mechanisms of force loss that occur during progressive muscular diseases are more and more studied using mouse models. Such diseases generally cause both a decrease in maximal tension and progressive muscle wasting, which may result in profound changes in muscle architecture. Muscle architecture is a main determinant of the mechanical behavior of skeletal muscle [1], and is charac...