Exploring the collision, acoustic and thermal energy dissipation distribution of discrete mass.

This research delves into the transfer and loss of energy in a discrete mass when subjected to forced vibration. Using discrete element method (DEM), we analyzed the dynamic behavior of regular spherical granular assemblies and the energy distribution characteristics under different excitation frequencies and reduced accelerations. Moreover, the energy transfer and dissipation process of granular assemblies under different vibration states are studied using an experimental method. The results show that the granular assemblies will produce collision energy dissipation, thermal energy dissipation, acoustic energy dissipation and other forms of energy dissipation in the forced vibration state and the proportion of different energy dissipation under different excitation is given. The collision and friction of granular assemblies are the key to affecting other forms of energy dissipation. When the excitation increases, the energy dissipation forms are generated inside the granular assemblies, and the proportion of collision energy dissipation of the granular assemblies increases. The acoustic energy above 20 kHz occupies the main part of the acoustic energy dissipation. Thermal energy consumption always exists, which takes a long time to play a role. The granular also have other forms of energy loss, which is hard to be measured, including Rayleigh waves generated by granular collision. In this study, the relationship between the forced vibration state of the granular assemblies and the energy loss distribution is established. Various types of energy transfer and conversion distribution which further enriches the energy dissipation of discrete element calculation of the granular assemblies is discussed and provides a reference for the energy loss analysis of the granular assemblies.

Human H-ferritin presenting RBM of spike glycoprotein as potential vaccine of SARS-CoV-2

The outbreak of COVID-19 has so far inflicted millions of people all around the world and will have a long lasting effect on every aspect of everyones life. Yet there is no effective approved treatment for the disease. In an effort of utilizing human ferritin as nanoplatform for drug delivery, we engineered a fusion protein by presenting receptor-binding motif (RBM) of SARS-CoV-2 virus spike glycoprotein on the N-terminus of ferritin subunits. The designed fusion protein with a cage-like structure, similar to that of corona virus, is a potential anti-SARS-CoV-2 vaccine. We hereby show the construction, preparation, and characterization of the fusion protein RBM-HFtn. Our initial affinity study confirmed its biological activity towards ACE2 receptor which suggests its mode of action against SARS-CoV-2 could be either through vaccine therapy or blocking the cellular entry of virus as antagonist of ACE2 receptor.