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Proposed is an ultra-low-profile loop antenna backed by an electromagnetic bandgap (EBG) surface reflector, where the EBG surface can effectively exhibit the property of a perfect magnetic conductor (PMC) inside a deliberately designed bandwidth. It is shown that, assisted by the effective PMC bandwidth, while the proposed antenna is with a 0.07-λ spacing between the loops and the EBG reflector, its axial ratio (AR) and voltage standing wave ratio (VSWR) performances are significantly improved. Experimental measurements show that the prototype antenna has a 3 dB AR bandwidth of 17% with an input VSWR less than 1.6. The proposed approach can find a wide range of low-profile circularly polarised (CP) antenna applications.

Aim: To obtain a recombinant enterotoxigenic Escherichia coli (ETEC) fusion enterotoxin protein LTB-STa-STb (Bab) that can express the immunogenicity of the haptens STa and STb and induce their corresponding neutralizing antibodies. Methods and Results: The three important ETEC enterotoxin genes coding LTB, STa and STb were PCR-amplified, and the amplified products were fused to construct the trivalent enterotoxin expression vector pET30-Bab. SDS-PAGE and Western blot were used to verify the expression of the fusion protein Bab by E. coli BL21 carrying plasmid pET30-Bab. Laying hens immunized with Bab developed high egg yolk immunoglobulin (IgY) titres specific to LTB, STa and STb, and all were significantly higher than those in the control group (P < 0Á01). A suckling mouse assay showed that anti-Bab IgY can neutralize the natural toxicity of STa and STb with the highest dilution of 1/2 and 1/32, respectively. Conclusions: Genetically constructed Bab induced significant antibody responses against STa and STb in chickens, and the resulting IgY had the capacity to neutralize the toxicity of ST. Significance and Impact of the Study: The recombinant Bab protein containing three important ETEC enterotoxins may serve as an effective and convenient polyvalent toxoid that can be used to produce multiple antitoxin IgYs to prevent colibacillosis caused by ETEC with various fimbriae in young animals.

A wideband conformal metasurface (MTS) antenna array with high gain is designed in this paper. The cooperation of the MTS and L-probe feeding of the antenna element realizes a wide bandwidth of 28.1%, which exhibits only one resonant mode. Then, the planar and conformal arrays consisting of 4×8 MTS antenna elements are investigated. The planar and conformal antenna arrays are fabricated and measured. The measured result shows that when the bending angle θ ≤ 10 o , unidirectional radiation and high gain can be maintained. The planar antenna array shows a measured impedance bandwidth (IMBW) of 2.81-3.76 GHz (0.95 GHz, 29.7%), with a peak gain of 22.2 dBi, and the conformal antenna array for the bending angle of 10 o exhibits an IMBW of 2.8-3.63 GHz (0.82 GHz, 25.6%), with a peak gain of 20.2 dBi.