Reconfigurable nested ring-split ring transmitarray unit cell employing the element rotation method by microfluidics

A continuously tunable, circularly polarized X-band microfluidic transmitarray unit cell employing the element rotation method is designed and fabricated. The unit cell comprises a double layer nested ring-split ring structure realized as microfluidic channels embedded in Polydimethylsiloxane (PDMS) using soft lithography techniques. Conductive regions of the rings are formed by injecting a liquid metal (an alloy of Ga, In, and Sn), whereas the split region is air. Movement of the liquid metal together with the split around the ring provides 360° linear phase shift range in the transmitted field through the unit cell. A circularly polarized unit cell is designed to operate at 8.8 GHz, satisfying the necessary phase shifting conditions provided by the element rotation method. Unit cell prototypes are fabricated and the proposed concept is verified by the measurements using waveguide simulator method, within the frequency range of 8-10 GHz. The agreement between the simulation and measurement results is satisfactory, illustrating the viability of the approach to be used in reconfigurable antennas and antenna arrays. © 2015 IEEE

Line x tester analysis and estimating combining abilities for yield and some yield components in bread wheat

Estimating of combining ability is useful to assess genotypes and elucidate the nature and magnitude of gene actions involved. Aim of this study was to determine the combining abilities of some wheat genotypes for yield and some yield related traits by using line x tester mating design. Four advanced wheat lines and one cultivar were used as lines and four wheat genotypes were used as testers. The specific combining ability (SCA) effects were generally found higher than general combining ability effects (GCA) in terms of the agronomic traits studied. As a result, low ratios of ?2GCA/?2sCA, (?2D/?2A)1/2 and low narrow sense heritabilities showed that non-additive effects controlled the traits studied. Hence, the selection process for superior individual plants should be postponed to further generations like F4 or F5. © 2015, Society of Field Crops Science. All rights reserved