Prediction of frequency band gaps in one-dimensional endohedral fullerene and carbon nano-onion chains.

Context: Acoustics have always played a central role in contemporary engineering, especially in the fields of communication, sensing, and even in more extraordinary applications such as non-invasive high-intensity focused ultrasound surgery. The rapid development of nano-scale-based technologies makes imperative the need for novel acoustic devices that take advantage of nanomaterials as well as their extraordinary physical properties. The successful design of such acoustic components requires the implementation of efficient nanostructures accompanied by fast and accurate modeling.

Tracking ankle joint movements during gait cycle via control of functional electrical stimulation.

Functional electrical stimulation (FES) is an effective method to induce muscle contraction and to improve movements in individuals with injured central nervous system. In order to develop the FES systems for an individual with gait impairment, an appropriate control strategy must be designed to accurate tracking performance. The goal of this study is to present a method for designing proportional-derivative (PD) and sliding mode controllers (SMC) for the FES applied to the musculoskeletal model of an ankle joint to track the desired movements obtained by experiments on two healthy individuals during the gait cycle.

Torsional Characteristics of Carbon Nanotubes: Micropolar Elasticity Models and Molecular Dynamics Simulation.

Efficient application of carbon nanotubes (CNTs) in nano-devices and nano-materials requires comprehensive understanding of their mechanical properties. As observations suggest size dependent behaviour, non-classical theories preserving the memory of body's internal structure via additional material parameters offer great potential when a continuum modelling is to be preferred. In the present study, micropolar theory of elasticity is adopted due to its peculiar character allowing for incorporation of scale effects through additional kinematic descriptors and work-conjugated stress measures.

Computational modeling of the effective Young's modulus values of fullerene molecules: a combined molecular dynamics simulation and continuum shell model.

Estimating the Young's modulus of a structure in the nanometer size range is a difficult task. The reliable determination of this parameter is, however, important in both basic and applied research. In this study, by combining molecular dynamics (MD) simulations and continuum shell theory, we designed a new approach to determining the Young's modulus values of different spherical fullerenes.

Persistence length of collagen molecules based on nonlocal viscoelastic model.

Persistence length is one of the most interesting properties of a molecular chain, which is used to describe the stiffness of a molecule. The experimentally measured values of the persistence length of the collagen molecule are widely scattered from 14 to 180 nm. Therefore, an alternative approach is highly desirable to predict the persistence length of a molecule and also to explain the experimental results.

A computational modeling of Raman radial breathing-like mode frequencies of fullerene encapsulated inside single-walled carbon nanotubes.

Raman radial breathing-like mode (RBLM) frequencies of an infinite nanopeapods are calculated within the framework of a continuum-molecular based model. The nanotube-fullerene interaction is modeled via the Lennard-Jones interatomic potential. An analytical formulation is developed and is justified due to its good agreement with the experimental and atomistic-based results.

Radial vibration of free anisotropic nanoparticles based on nonlocal continuum mechanics.

Radial vibration of spherical nanoparticles made of materials with anisotropic elasticity is theoretically investigated using nonlocal continuum mechanics. The anisotropic elastic model is reformulated using the nonlocal differential constitutive relations of Eringen. The nonlocal differential equation of radial motion is derived in terms of radial displacement.

Prediction of bending stiffness and deformed shape of non-axially compressed microtubule by a semi-analytical approach.

The bending stiffness of a microtubule is one of the most important parameters needed in the analysis of microtubule deformation. In this study, a semi-analytical approach is developed to predict the bending stiffness and deformed shape of a non-axially compressed microtubule in an explicit closed form. By using the solution presented in this paper and the experimentally observed values given in the literature, both the deformed configuration and bending stiffness of a single microtubule are determined.

Wave propagation in protein microtubules modeled as orthotropic elastic shells including transverse shear deformations.

Wave propagation along the microtubules is one of the issues of major concern in various microtubule cellular functions. In this study, the general wave propagation behavior in protein microtubules is investigated based on a first-order shear deformation shell theory for orthotropic materials, with particular emphasis on the role of strongly anisotropic elastic properties of microtubules. According to experimental observation, the first-order shear deformation theory is used for the modeling of microtubule walls.