On the use of bianisotropic huygens' metasurfaces to build leaky-wave antennas

The Electromagnetics AcademyHuygens' metasurfaces are considered a powerful tool to achieve anomalous electromagnetic field transformations. They consist of an artifcial surface built of pairs of collocated electric and magetic dipoles that force the boundary conditions for the desired transformation to be ful lled [1]. Despite their possibilities, the achievable transformations must ful l some conditions. In [2] it was shown that Huygens' metasurfaces with passive and lossless particles can achieve an arbitrary field transformation provided that the power is conserved at each point of the metasurface and there is wave impedance matching. However, it was shown in [3], that by introducing bianisotropy of the omega-type, the matching condition can be suppressed, which allows the control of both the transmission and rejection coe cients on the metasurface.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Experimental Verification of a Leaky-Wave Antenna Based on Bianisotropic Huygens’ Metasurface

Abstract—In this communication, the experimental verification of a leaky-wave antenna that uses a Huygens’ metasurface to have a control on the radiation parameters is addressed. The antenna consists of a parallel-plate waveguide in which the top plate has been replaced by an omega-type bianisotropic Huygens’ metasurface, in order to transform the guided mode into the desired leaky-mode with arbitrary choice of the leakage rates, pointing direction and waveguide height. The physical implementation of the metasurface is explained. Two design examples, radiating at broadside with different leakage factors, are implemented, manufactured and measured. Simulated and experimental results of the achieved directivity, scanning performance and radiation patterns are provided, experimentally corroborating the conceptUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 706334

Protein structure protection commits gene expression patterns

A proteomic association study between protein three-dimensional structure and transcriptional and post-transcriptional regulation in yeast and human

Non-coding RNAs in Transcriptional Regulation

Transcriptional gene silencing guided by small RNAs is a process conserved from protozoa to mammals. Small RNAs loaded into Argonaute family proteins direct repressive histone modifications or DNA cytosine methylation to homologous regions of the genome. Small RNA-mediated transcriptional silencing is required for many biological processes, including repression of transposable elements, maintaining the genome stability/integrity, and epigenetic inheritance of gene expression. Here, we will summarize the current knowledge about small RNA biogenesis and mechanisms of transcriptional regulation in plants, Drosophila, Caenorhabditis elegans, and mice. Furthermore, a rapidly growing number of long non-coding RNAs (lncRNAs) have been implicated as important players in transcription regulation. We will discuss current models for long non-coding RNA-mediated gene regulation

EFFECTS OF ONE AND TWO HANDED TENNIS BACKHANDS HIT WITH VARIED POWER LEVELS ON TORSO ROTATION

This study examined hitting one & two hand backhands with moderate and maximal power on the shoulder, hip, and trunk rotations during a tennis groundstroke by collegiate male and female tennis players. Video images from two views at 60 Hz were collected as players hit backhand strokes with a ball launched from a serving stand. Each subject hit 10 trials with moderate and maximal power using one & two hand backhands to a 2x2 m target area. Average ball velocities for stroke conditions were determined and 2 trials closest to the condition average velocity were analyzed with Ariel APAS. ANOVA on the shoulder rotations found significant hand and power factors, where maximal power and two hand backhands used more shoulder motion. The two hand backhand produced greater hip rotation and the female subjects used more trunk rotation with a two handed backhand