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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. [ABSTRACT FROM AUTHOR]

The application of dual-polarization microstrip array antenna in mono-pulse radar system is introduced. The radar system may achieve polarization diversity and multi-polarization angle error extraction abilities with this design. A mono-pulse antenna array is accomplished with two dual-polarization sub-arrays. Amplitude comparing angle error extraction method and polarization synthesize technique are absorbed to obtain sum and difference beam patterns and angle error curves in linear, circular and ellipse polarization waves. A low cost two dimensional mono-pulse antenna array is also represented. Both azimuth and pitch angle error extraction methods are introduced. The results show the feasibility of dual-polarization mono-pulse antenna based on stacked structure. [ABSTRACT FROM AUTHOR]

The development of a Ka-band monopulse variable polarization antenna is presented, based on polarization synthesis theory. This kind of microstrip array antenna consists of several linearly polarized subarrays of rotational symmetry, and change the polarization mode by adjusting the phase of each subarray. The circular polarization of three subarrays and four subarrays has high polarization purity with over 30 dB cross-polarization and less than 3 dB axial ratio within the half power beamwidth; and the imbalance of two peaks in difference beam is less than 1 dB, and null depth is over 30 dB. [ABSTRACT FROM AUTHOR]

A novel double vertical half-wavelength dipole antenna is studied. Its main structure and advantages of this novel antenna is presented. 3D electromagnetic numerical method is utilized to analyse and simulate the antenna performance. Measurement results proved that the realized antenna has good electrical performance in operating bandwidth, voltage standing wave ratio(VSWR) and antenna pattern. It also has a high ratio of performance to cost. Finally, application of the antenna in portable tree surveillance radar and large scale air surveillance radar is discussed. [ABSTRACT FROM AUTHOR]