A Method to Calculate the AIS Trauma Score from a Finite Element Model

In the real world, traumatic injuries are measured using the Abbreviated Injury Scale (AIS), however, such a scale cannot be computed to date or the injury precisely located by using human computer models. These models use stresses and strains to evaluate whether serious or fatal injuries are reached, which unfortunately bear no direct relation to AIS. This paper proposes to overcome this deficiency and suggests a unique Organ Trauma Model (OTM) able to calculate the risk to life of any organ injury, focussing in this case on real-life pedestrian head injuries. The OTM uses a power method, named Peak Virtual Power (PVP), and defines a brain white and gray matters trauma response as a function of impact direction and impact speed. The OTM was tested against four real-life pedestrian accidents and proved to predict the head trauma severity and location. In some cases, the method did however under-estimate the trauma by 1 AIS level because of post-impact haemorrhage which cannot be captured with Lagrangian Finite Element solvers. The OTM has the potential to create an important advance in vehicle safety by adding more information on the risk of head trauma.</p

A Single-domain Protein Catenane of Dihydrofolate Reductase

A single-domain protein catenane refers to two mechanically interlocked polypeptide rings that fold synergistically into a compact and integrated structure, which is extremely rare in nature. Herein, we report a single-domain protein catenane of dihydrofolate reductase (cat-DHFR). The design was achieved by rewiring the connectivity between secondary motifs to introduce artificial entanglement and the synthesis was readily accomplished by a series of programmed streamlined post-translational processing events in cells without any additional in vitro reactions. The target molecule contains few exogenous motifs and has been thoroughly characterized by combined techniques of LC-MS, SDS-PAGE, protease cleavage experiment, and ion mobility mass spectrometry. Compared to the linear control, cat-DHFR retains the catalytic capability and exhibits enhanced stability against thermal or chemical denaturation due to conformational restriction. The results suggest that linear proteins may be converted into concatenated single-domain counterparts with almost identical chemical composition, well-preserved function, and elevated stability, which represents an entirely new horizon in protein science