Size- and concentration-dependence of antiviral and virucidal activity of Au nanoparticles against adenoviruses and influenza viruses H1N1

Over the past 10 years, many scientific groups have experimentally shown that non-functionalized nanoparticles show a pronounced antiviral and antimicrobial action against different pathogens. In order to understand the mechanism of nanoparticles action it is important to know its peculiarities, i.e. dependences on different nanoparticles and pathogen properties.In this work we studied how Au nanoparticles act on the viruses outside and inside the cell, and compare this action for two sizes of nanoparticles and two types of the viruses. The study has been conducted for adenovirus and H1N1 influenza virus, and nanoparticles of 5 nm and 20 nm diameter.Virucidal and antiviral actions were observed experimentally for both types of nanoparticles against both viruses. It has been shown that intensity of virucidal action depends on the nanoparticles concentration non-monotonically for adenovirus. It has also been shown with electron microscopy that the viruses are destructed after 5 nm nanoparticles adsorption on their surface; and that the viruses change their shape after 20 nm nanoparticles adsorption on their surface. The model of physical adsorption of nanoparticles on the virus surface due to near-field interaction proposed in previous works may explain observed results on virucidal action of nanoparticles.

A Mode Decoupling Method for Circular Patch Antennas

In this contribution, we investigate the effect of mode decoupling for dual-feed circular patch antennas. We consider an antenna comprising a circular disc patch placed inside an annular-ring patch. Both patches are resonant radiators, which can be fed by two different vertical posts. Due to the field interaction of the patches, the feeds experience parasitic cross-talk limiting the receive diversity performance of the system. Here, we demonstrate the possibility to suppress the cross-talk at the operational frequency by including a capacitive decoupling element into the circular patch. The physical mechanism of the method consists in the excitation of two different eigenmodes (TM01 and TM11) in a certain combination canceling the mutual coupling. The presented decoupling method can be used for patches operating either at the same frequency or at two different frequencies. In the proposed dual-feed antenna it is possible to achieve an isolation level of better than -45 dB. In contrast to the method of decoupling and matching network used for the same type of antennas, one does not need couplers to feed the patches, which reduces losses.

Gravitational-Magnetic-Electric Interaction in Controlling Relative Permittivity and Permeability

Appling the controlling relative permittivity and permeability in the equations for the gravitational-magnetic-electric field interaction, a very large variation of the gravitational acceleration of the Earth by electric/magnetic field could be arrived at. This conclusion may be supported by some of the experiments for the gravitational effect of superconductivity.