The breeding method of Toth and Kalnay, developed for atmospheric data assimilation studies, is applied to a global ocean model in order to identify instabilities as a function of timescale. In addition to exploring its usefulness in the oceanic context, this study extends the method to show how the energy equations for the bred vectors can be used to assess the characteristics of the instabili...

In this paper, we investigate theoretically the possible development of instabilities in fiber-reinforced elastomers (and other soft materials) when they are subjected to finitestrain loading conditions. We focus on the physically relevant class of ‘‘macroscopic’’ instabilities, i.e., instabilities with wavelengths that are much larger than the characteristic size of the underlying microstructu...

When a stably stratified density interface is embedded in a region of strong velocity shear, hydrodynamic instabilities result. Here we generalize the stratified shear layer to allow an offset between the centre of the shear layer and the density interface. By including this asymmetry, and keeping the density interface thin with respect to the shear layer, the asymmetric Holmboe (AH) instabilit...

When dealing with complex mechanical systems that include sliding contact, it is necessary to account for the coupling between the dynamic behavior of the system and the local behavior at the contact. A particular consequence of interaction between system dynamics and contact behavior is the occurring of vibrational instabilities of the mechanical system, induced by the frictional contact. The ...

We investigate the gravonuclear instabilities reported by Bono et al. (1997a,b) during the onset of helium-shell burning at the end of the horizontal-branch (HB) phase. These instabilities are characterized by relaxation oscillations within the helium shell which lead to loops in the evolutionary tracks. We find the occurrence of these instabilities depends critically on how the breathing pulse...

Under tension, confined elastic layers can exhibit various modes of mechanical instabilities, including cavitation, fingering and fringe instabilities. While the cavitation has been extensively studied, the fingering and fringe instabilities have not been well understood, and the relations and interactions of these instabilities have not been explored yet. In this paper, we systematically study...

Beam instabilities in the strongly magnetized electron-positron plasma of pulsar magnetospheres are considered. We analyze the resonance conditions and estimate the growth rates of the Cherenkov and cyclotron instabilities of the ordinary (O), extraordinary (X) and Alfvén modes in two limiting regimes: kinetic and hydrodynamic. As a preliminary step, we reconsider wave dispersion and polarizati...

Lipid bilayers membranes, positioned between two solutions, are the barrier of the cell and its internal components (organelles). Membranes define the cell limit and, by allowing the existence of two different solutions in close proximity, enable their functions. Membranes participate in various biological processes such as cell-cell adhesion, controlled ions transfer, and signal transduction. ...

We find instabilities and self-pulsation in an optical ring cavity with a photorefractive two-wave mixer. The mean field limit is used to obtain a single criterion for instabilities that originate from a Hopf bifurcation.

BACKGROUND The integrity of the glenoid defines the surgical treatment in anterior shoulder instabilities. The reliability of plain radiographs to detect anterior glenoid rim deficiencies was determined. MATERIALS AND METHODS The anterior sclerotic glenoid line (SGL) was assessed on anteroposterior radiographs of 86 shoulders (34 anterior instabilities, 15 posterior instabilities, 37 stable) ...