Abstract-A novel miniaturized dual-band bandstop filter (DBBSF) is proposed by using the T-shaped defected microstrip structures (DMSs) and the U-shaped defected ground structures (DGSs) in this paper. The layout of the dual-band bandstop resonator (DBBSR) is presented at first. The dual stopbands of the DBBSR can be separately controlled since the mutual coupling of the defected structures is negligible. The working principles of the T-shaped DMS and U-shaped DGS are then provided and their design process is summarized. On the basis of the DBBSR, the design methodology of the compact DBBSF is proposed before its design procedures are presented. Following the design procedures, a second-order and thirdorder DBBSFs with Butterworth frequency response are designed, simulated and fabricated. The equivalent circuit models of the designed filters are also developed. Full-wave simulation results of the fabricated DBBSFs are in good agreement with the circuit simulation and measurement results, validating our proposed design methodology.

No abstract

No abstract

A cascaded trisection substrate-integrated waveguide bandpass filter with better frequency selectivity is presented. The proposed coupling scheme can be divided into two trisection topologies. By changing the signs of coupling coefficients between cascaded resonators, two transmission zeros can be simultaneously placed at the higher or lower stopband, or one can be located below and the other above the passband. A filter sample is designed and fabricated with standard single-layer printed circuit board technology. The measured S-parameters agree well with the simulated counterparts, and good performance of the filter is predicted.

No abstract

The Chinese cantaloupe (cv. Yujinxiang) fruit was used to investigate the inhabiting mechanisms of silicon compounds against Fusarium rot (Fusarium spp.). When silicon compounds were applied as a dipping solution, both silicon oxide and sodium silicate significantly (P < 0.01) reduced the infection rate of Fusarium spp. But the mechanisms involved in silicon oxide‐ and sodium silicate‐mediated resistance of cantaloupe to postharvest Fusarium rot were different. In vitro tests showed that sodium silicate was effective in suppressing the mycelial radial growth of the pathogen (P < 0.01) on potato dextrose agar, while silicon oxide was ineffective (P > 0.01). The effectiveness of sodium silicate increased with concentration, and the growth of the pathogen was completely inhibited at 100 mmol/L. Significantly enhanced peroxidase activities at 24 h after sodium silicate treatment and 72 h after inoculation, and phenylalanine ammonia‐lyase activities at 24 and 72 h after inoculation were observed in sodium silicate‐treated melons but not in those treated with silicon oxide. Scanning electron microscopy–energy dispersive X‐ray analysis showed that Si‐treated melons had a smoother surface feature and higher Si content in the epidermis, especially at the stomata and the junction between the exocarp and mesocarp. PRACTICAL APPLICATIONS Silicon is one of the most abundant materials on the surface of the earth. Some evidences have shown that silicon is related to the disease resistance of plants; we think this might be employed to develop nonpolluting chemicals for the postharvest disease control of plants. Until now, fungicides have been most commonly used to control postharvest diseases of fruits; however, chemical residues and chemical resistance of pathogens are always problems as well. In the present work, we used the silicon agents to control the postharvest fungal disease of Chinese cantaloupe, and a positive result was shown. Although the mechanism involved in Si resistance of plants to fungus is not yet fully understood, our result showed that silicon might be used as a promising ingredient of preservatives for Chinese cantaloupe as well as other fruits and vegetables in the future.

A novel microstrip lowpass filter (LPF) with compact size is proposed to achieve sharp skirt characteristic and wideband suppression. The sharp transition and good passband performance of the proposed LPF is obtained by employing the defected microstrip structure, while the wide stopband is implemented by properly locating the open stubs, spurline, and dumbbell‐shaped defected ground structure. Both the simulation and measurement are conducted to verify the behavior of the proposed filter, and a good agreement between the measured and simulated results is observed. The experimental result of the fabricated filter shows that the attenuation rate reaches 159 dB GHz−1 and the stopband with good rejection level is obtained from 4.07 GHz to more than 15 GHz. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1085–1088, 2016

Biomimetic therapeutics offer great potential for drug delivery that avoids immune recognition. However, the coated cell membrane usually hinders the cellular uptake of nanoparticles; thus, structure-changeable formulations have attracted increasing attention. Herein, we report photolytic pyropheophorbide a (PA)-inserted red blood cell (RBC) membrane-camouflaged curcumin dimeric prodrug (CUR 2 -TK)−poly(lactic-co-glycolic acid) (PLGA) nanoparticles [(CUR 2 -TK)-PLGA@RBC-PA] for enhanced cancer therapy. In these nanoparticles, the inner core was constructed using PLGA and loaded with our synthesized reactive oxygen species (ROS)-responsive cleavable curcumin dimeric prodrug (CUR 2 -TK). The nanoparticles generated ROS in response to the light irradiation attributed to the incorporated PA. The ROS further triggered the lysis of the cell membrane and exposed the nanoparticles for enhanced tumor cellular uptake, and the ROS also cleaved CUR 2 -TK for controlled CUR drug release. Moreover, the ROS performed photodynamic therapy (PDT). The chemotherapy and PDT produced a combined effect in the treatment of cancer cells, thus enhancing anticancer therapeutic efficacy.