BACKGROUND Strain rate (SR) imaging (SRI) is a tissue Doppler-based method of regional myocardial deformation imaging. The aim of this study was to see whether SRI could quantify changes in myocardial mechanical function after an acute myocardial infarction, and to follow the time course of these changes. METHODS In all, 26 consecutive patients with first-time acute myocardial infarctions wer...

At room temperature, plastic flow of metallic glasses (MGs) is sharply localized in shear bands, which are a key feature of the plastic deformation in MGs. Despite their clear importance and decades of study, the conditions for formation of shear bands, their structural evolution and multiplication mechanism are still under debate. In this work, we investigate the local conditions at shear band...

In 1985, 1987 and 1988, we measured deformation of bore holes in the ablation zone of Storglaciaren. A different hole was used each year. Deformation profiles were determined for four consecutive time periods between mid-July and early September. All three holes were in an area where the glacier lies in an overdeepened part of the bed, up-glacier from a riegel. The first hole was approximately ...

We study the impact of strain localization on the stability of frictional slipping in dense amorphous materials. We model the material using shear transformation zone (STZ) theory, a continuum approximation for plastic deformation in amorphous solids. In the STZ model, the internal state is quantified by an effective disorder temperature, and the effective temperature dynamics capture the spont...

An empirical method of non-destructive testing of a material was developed using pulse transmission by acoustic emission transducers to determine plastic deformation of 304 stainless steel specimens. This was done by means of comparison of pulse signals detected in an undeformed section with the pulse signals detected after passing through the deformation zone in the specimens. The pulse signal...

Deformation in the Earth is rarely homogeneous and often occurs in narrow regions of concentrated strain referred to as zones of shear localization. Mylonites found in the continental crust are the manifestation of shear localization (White et al. 1980) and, at the largest scale, shear localization is proposed to be crucial for the generation of tectonic plates from a convecting mantle (Bercovi...

We use considerations of energy balance and dissipation to derive a self-consistent version of the shear-transformation-zone (STZ) theory of plastic deformation in amorphous solids. The theory is generalized to include arbitrary spatial orientations of STZs. Continuum equations for elasto-plastic material and their energy balance properties are discussed.

New shear wave splitting measurements made from stations onshore and offshore the South Island of New Zealand show a zone of anisotropy 100–200km wide. Measurements in central South Island and up to approximately 100 km offshore from the west coast yield orientations of the fast quasi-shear wave nearly parallel to relative plate motion, with increased obliquity to this orientation observed fart...

In this study, 5052 Al–Mg alloy was pre-treated and friction stir processing (FSP) was then performed on the specimens to explore the deformation resistance. The experimental results indicate that the FSP specimens not only had better tensile properties but also better vibration fracture resistance. It is significant that the tensile elongation and deformation resistance tended to increase as t...

[1] The estimation of uniform viscosities representing the lower crust and uppermost mantle from postseismic or interseismic deformation (i.e., apparent viscosities) is inherently biased with respect to a depth dependence of the viscosities within each layer. Estimates are biased toward a more viscous lower crust or a less viscous lithospheric mantle, depending on the relative geometric mean vi...