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Apolygus lucorum is the dominant pathogenic insect attacking Bacillus thuringiensis (Bt) cotton in China. Additionally, 20-hydroxyecdysone (20E) has important functions in many biological processes, including insect reproduction. Phospholipase C (PLC), which is an essential enzyme for phosphoinositide metabolism, is involved in 20E signal transduction, but its function in 20E-mediated reproduction in A. lucorum remains unclear. In this study, 20E increased AlPLCγ transcription as well as the abundance and activity of the encoded protein during molting and metamorphosis. The 20E treatment also induced the considerable accumulation of two second messengers, inositol triphosphate and diacylglycerol. The expression levels of genes encoding vitellogenin (AlVg) and soluble trehalase (AlTre-1) were similar to those of AlPLCγ, and were upregulated in response to 20E. The silencing of AlPLCγ resulted in downregulated expression of AlTre-1 and AlVg. However, the silencing of AlTre-1 and AlVg did not affect AlPLCγ expression. Moreover, the silencing of AlVg did not alter AlTre-1 expression. Furthermore, an examination of the insect specimens indicated that AlPLCγ is required for female adult reproduction, and that downregulated expression of this gene is associated with decreases in fecundity, adult longevity, and egg hatching rate as well as delayed oocyte maturation. We propose that 20E regulates AlTre-1 expression via AlPLCγ and affects Vg expression as well as ovary development to facilitate the reproductive activities of A. lucorum females.

This letter introduces a W-band full-polarization monopulse antenna based on the sequential rotate polarization theory. The proposed antenna consists of a main reflector, a subreflector, and a sequential rotate polarization feed to realize full-polarization monopulse angle measurement. The circular polarization monopulse patterns are simulated and measured by using special amplitude and phase setting. The measured results are in good agreement with the simulated ones. The SUM beam gain of the proposed antenna is 36.1 dBi by eliminating the loss of W-band comparator, cross-polarization level is better than −23 dB, and 3-dB beamwidth is 1.65°. The first sidelobe level is under −17 dB. The gain ratio between the SUM and DIFF beams is 5.5 dB. The proposed antenna is a good candidate for W-band full-polarization monopulse detector.

A novel S-band antenna is proposed in this paper. The antenna consists of two layers of radiant dipole. The unit is capable of realizing broad beam-width of 144° in E-plane with isolation better than -35dB between two ports. The circular polarization can be achieved by exciting two ports with equal amplitude and 90° phase difference. Moreover, the axial ratio is less than 2dB in the antenna operating frequency band. At last, a triangular grid array with 64 elements is designed. The simulated results show that the designed array can meet the requirements of large scanning angle. It can be applied for the fifth generation mobile communications (5G) Multiple-Input Multiple-Output (MIMO)base station.

Strong magnetoelectric (ME) coupling can be realized in multiferroic heterostructures, which have led to a variety of devices. Here, a novel electrostatically tunable frequency selective surface (FSS) with PZT/FeGaB films is reported, which shows a high resonant frequency tunability. A high X to Ku band resonant frequency tunability of f = 2.75 GHz or f/f= 24% was demonstrated in the FSS with PZT/FeGaB films, which was 10 times of the similar FSS structure with only FeGaB film. This electrostatically tunable FSS with strong ME coupling will provide great opportunities for more energy efficient, less noisy, compact and light-weight microwave devices with frequency tunabilities.

This paper uses modern spectrum setimation to process stepped-frequency signals which have extracted to obtain high resolution range profile. This paper use FPE criteria and AIC criteria to estimate the order of AR model, and linear prediction is used to test the performance of AR model. Compared with conventional IFFT processing, the results of spectrum estimation is satisfactory, and the exact location of high resolution range profile is determined.

For avoidance of any intrusion disturbing the flow in a viscous sublayer, a biprism shear strain-rate meter has been developed. The biprism shear strain rate meter utilizes the linear distribution characteristics of velocity in the viscous sublayer. It can measure shear strain rate directly and give an instantaneous value. The skin friction of two-dimensional channel flow has been investigated by means of the biprism shear strain-rate meter. Results of an experiment in laminar flow agree quite well with theoretical prediction. Results in turbulent flow may be expressed as C/sub f/=0.12/Re/sub B//sup 0.339/, where C/sub f/ is the skin friction coefficient, and Re/sub B/ is the Reynolds number in terms of channel width B. >