Interactions and assemblies of wheat proteins

International audienceInteractions and assemblies of wheat protein

Phase separation dynamics of gluten protein mixtures

We investigate by time-resolved synchrotron ultra-small X-ray scattering the dynamics of liquid-liquid phase-separation (LLPS) of gluten protein suspensions following a temperature quench. Samples at a fixed concentration (237 mg ml-1) but with different protein compositions are investigated. In our experimental conditions, we show that fluid viscoelastic samples depleted in polymeric glutenin phase-separate following a spinodal decomposition process. We quantitatively probe the late stage coarsening that results from a competition between thermodynamics that speeds up the coarsening rate as the quench depth increases and transport that slows down the rate. For even deeper quenches, the even higher viscoelasticity of the continuous phase leads to a "quasi" arrested phase separation. Anomalous phase-separation dynamics is by contrast measured for a gel sample rich in glutenin, due to elastic constraints. This work illustrates the role of viscoelasticity in the dynamics of LLPS in protein dispersions

The use of accident reconstruction for the analysis of traumatic brain injury due to head impacts arising from falls

Brain injury is the leading cause of death in those aged under 45 years in both Europe and the USA. The objective of this research is to reconstruct and analyse real world cases of accidental head injury, thereby providing accurate data, which can be used subsequently to develop clinical tolerance levels associated with particular traumatic injuries and brain lesions. This paper looks at using numerical modelling techniques, namely multibody body dynamics and finite element methods, to reconstruct two real-life accident cases arising from falls. Preliminary results show the levels of acceleration of the head and deformation of brain tissue correspond well to those found by other researchers, suggesting that this method is suitable for modeling head-injury accidents.Deposited by bulk import1/10/2013. SB