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How do people hear sounds? As a counterpart of Prof. G. V. Békésy's traveling wave theory, we have proposed resonance theory of outer hair cells and cochlear standing wave theory, respectively. Based on these proposals, this paper develops a transmission-line-based cochlear standing wave model. Since the macroscopic cochlear model is designed as it looks like, various auditory physiology can be explained. Transient analyses with pure-tone excitation and Gaussian pulse excitation are carried out, and Prof. D. Kemp's otoacoustic emission (OAE) is demonstrated successfully.Clinical relevance-Our new model has a great potential to explain auditory physiology including structural inner disorders, hearing loss, and even tinnitus.Existing computational studies of cochlear implants have demonstrated that the structural detail of threedimensional (3D) cochlear models exerts influence on the current spread within the cochlea. Nevertheless, the significance of including the microstructures inside the modiolar bone in a cochlear model is still unclear in the literature. We employed two different multi-compartment neuron models to simulate auditory nerve fibres, and compared response characteristics of the fibre population between a detailed and a simplified 3D cochlear model. Results showed that although the prediction of firing is dependent on the details of the neuron model, the responses of the fibre population to the electrical stimulus, especially the location of the initiation of action potential, varied between the detailed and the simplified models. Therefore, the inclusion of the modiolar microstructures in a cochlear model may be necessary for fully understanding the firing of auditory nerve fibres.This paper proposes a computational framework for automatically optimizing the shapes of patient-specific tissue engineered vascular grafts. We demonstrate a proof-of-concept design optimization for aortic coarctation repair. The computational framework consists of three main components including 1) a free-form deformation technique exploring graft geometries, 2) high-fidelity computational fluid dynamics simulations for collecting data on the effects of design parameters on objective function values like energy loss, and 3) employing machine learning methods (Gaussian Processes) to develop a surrogate model for predicting results of high-fidelity simulations. The globally optimal design parameters are then computed by multistart conjugate gradient optimization on the surrogate model. In the experiment, we investigate the correlation among the design parameters and the objective function values. Our results achieve a 30% reduction in blood flow energy loss compared to the original coarctation by optimizing the aortic geometry.Dialysis is prescribed to renal failure patients as a long-term chronic treatment. Whereas dialysis therapeutically normalizes serum electrolytes and removes small toxin molecules, it fails to alleviate fibroblast induced structural fibrosis, and unresponsive uremia. The simultaneous presence of altered electrolytes and fibrosis or uremia is thought to be pro-arrhythmogenic. This study explored potential arrhythmogenesis under pre-dialysis (high electrolyte levels) and post-dialysis (low physiological electrolyte levels) in the presence of fibrosis and uremia in human atrial and ventricular model cardiomyocytes.Two validated human cardiomyocyte models were used in this study that permitted simulation of cardiac atrial and ventricular detailed electrophysiology. Pathological conditions simulating active fibrosis and uremia were implemented in both models. Pre- and post-dialysis conditions were simulated using high and low electrolyte levels respectively. Arrythmogenesis was quantified by computing restitution re additional treatment to improve dialysis outcomes.Clinical Relevance. Knowledge of model response to clinically relevant conditions permits use of in silico modeling to better understand and dissect underlying arrhythmia mechanisms.Models of muscle contraction are typically based on a measured force-velocity relation embodied as Hill's contractile element [1]. Adopting a particular force-velocity relation dictates the muscle's mechanical properties. Dynamic crossbridge based models, such as Huxley's [2], typically focus on ultrastructural mechanics. This study adapts a dynamic lumped model of cardiac muscle contraction [3] for description of mouse soleus skeletal muscle. This compact, dynamic model exhibits the main features of skeletal muscle contraction with few assumptions. The main differences between cardiac and skeletal muscle dynamics are described. This approach gives one equation and set of parameters capable of modeling isometric and isotonic contractions, skeletal muscle's force-length relation, variations in contractility, and the force-velocity relation. This new constitutive equation may be useful for modeling striated muscle as part of larger biomechanical models.Electrical impedance spectroscopy (EIS) is a fast, non-invasive, and safe technique for bioimpedance measurement. In dental research, EIS has been used to detect tooth cracks and caries with higher accuracy than visual and radiographic methods. learn more Recently, a study has been reported on effect of age on impedance measurements for two age groups by employing EIS. The aim of that study was to demonstrate the usefulness of fractional calculus in equivalent circuit modeling. In proposed double dispersion Cole impedance (C-C) models, both resistance and pseudo-capacitance values were found to be significantly different for both age groups. However, in our study, the first time it was found out that proposed models' total pseudo-capacitance values of both young and old dentines can be reduced by 34% and 7.5%, respectively, if recurrent electrical impedance model for n = 2 bifurcations to be used. Secondly, new empirical fractional-order electrical models of human tooth using the optimized Valsa network with EIA standard compliant RC values are reported that provide better understanding of the structure of dentine from resistance and capacitance point of view.