Ultrashort echo time magnetic resonance elastography for quantification of the mechanical properties of short T2 tissues via optimal control-based radiofrequency pulses.

The aim of the current study is to demonstrate the feasibility of radiofrequency (RF) pulses generated via an optimal control (OC) algorithm to perform magnetic resonance elastography (MRE) and quantify the mechanical properties of materials with very short transverse relaxation times (T2 < 5 ms) for the first time. OC theory applied to MRE provides RF pulses that bring isochromats from the equilibrium state to a fixed target state, which corresponds to the phase pattern of a conventional MRE acquisition. Such RF pulses applied with a constant gradient allow to simultaneously perform slice selection and motion encoding in the slice direction.

Dill Extract Preserves Dermal Elastic Fiber Network and Functionality: Implication of Elafin.

Introduction: Elastic skin fibers lose their mechanical properties during aging due to enzymatic degradation, lack of maturation, or posttranslational modifications. Dill extract has been observed to increase elastin protein expression and maturation in a 3D skin model, to improve mechanical properties of the skin, to increase elastin protein expression in vascular smooth muscle cells, to preserve aortic elastic lamella, and to prevent glycation.

Objective: The aim of the study was to highlight dill actions on elastin fibers during aging thanks to elastase digestion model and the underlying mechanism.

Shear Properties of Brain Tissue over a Frequency Range Relevant for Automotive Impact Situations: New Experimental Results.

This research aims at improving the definition of the shear linear material properties of brain tissue. A comparison between human and porcine white and gray matter samples was carried out over a new large frequency range associated with both traffic road and non-penetrating ballistic impacts. Oscillatory experiments were performed by using an original custom-designed oscillatory shear testing device.