In this article, we examine the elastic properties of boron-nitride nanotubes, which are embedded in amorphous silicon-boron-nitride ceramics. We employ molecular dynamics simulations using the Parrinello-Rahman approach. To this end, all systems are modeled with a reactive many-body bond order potential due to Tersoff, which is able to describe covalent bonding accurately. We apply external st...

We present a theoretical model to calculate the flexural rigidity of nanowires from three-dimensional elasticity theory that incorporates the effects of surface stress and surface elasticity. The unique features of the model are that it incorporates, through the second moment, the heterogeneous nature of elasticity across the nanowire cross section, and that it accounts for transverse surface-s...

We have studied the strain-rate dependency of the viscoelastic mechanical properties of human dermis from young (23-year-old) and old (87-year-old) donors using incremental stress–strain measurements. The elastic spring constant for elastic fibers was found to be strain-rate and age dependent, whereas that for collagen was only age dependent. Fibril lengths were observed to decrease with increa...

A variational limit defined on the space of one-dimensional Young measures is obtained from three-dimensional elasticity via dimension reduction. The physical requirement that the energy becomes infinite when the volume locally vanishes is taken into account. The rate at which it blows up characterizes the domain of the limit energy. The obtained limit problem uniquely determines the energy den...

The elastic fiber consists of several components: a central core of alpha-elastin and a microfibrillar sheath containing three components: fibrillin, microfibril-associated glycoprotein, and a 35-kD protein with amine oxidase activity. Elastin is a major component of the elastic fibers of the extracellular matrix (ECM) of the lamina cribrosa, and elastic fibers undergo marked changes in primary...

Here we describe modifications that allow the bone diagnostic instrument (BDI) [P. Hansma et al., Rev. Sci. Instrum. 79, 064303 (2008); Rev. Sci. Instrum. 77, 075105 (2006)], developed to test human bone, to test the femora of mice. These modifications include reducing the effective weight of the instrument on the bone, designing and fabricating new probe assemblies to minimize damage to the sm...

Thermodynamic analysis and molecular dynamics simulations were conducted to systematically study the size-dependent electrochemical response of solids. By combining the generalized Young-Laplace equation with the popular Butler-Volmer formulation, the direct influence of surface stress on solid film electrochemical reactions was isolated. A series of thermodynamic formulas were developed to des...

BACKGROUND Excessive stiffness of lower limb muscles is associated with sports injuries. Therefore, the identification of a reliable measurement of the shear elastic modulus of various ankle plantar flexion muscles is required to evaluate lower leg sports injuries. This study investigated the reliable measurement of the shear elastic modulus of the ankle plantar flexion muscles at different ank...

By combining molecular dynamics simulations and analytical arguments, we investigate the elastic properties of charged lipid bilayers. We show that electrostatic interactions between the head groups can lead to solidification of the lipid bilayer that would otherwise be in a liquid state if the charges were absent. All elastic parameters of the bilayer such as the bending rigidity κ and the two...

The trabecular meshwork and scleral spur of two young human eyes were studied by light and electron microscopy in Epon-embedded material. Anteroposterior sections showed, in light microscopy, numerous dots stained dark purple with Weigert's elastic stain and greenish with Giemsa in both regions. In tilted frontal sections, similarly stained, long, circularly oriented fibers toere observed, indi...