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Objective. To explore the related mechanism of acupuncture affecting obesity by regulating inflammation using bioinformatics methods. Methods. The genes related to obesity, inflammation, and acupuncture and inflammation were mined using GenCLiP 3, and the intersecting genes were extracted using Venn diagram. The DAVID database was employed for pathway enrichment analysis and functional annotation of coexpressed genes. Then, the protein-protein interaction (PPI) network was constructed with the STRING database and visualized by the Cytoscape software and screened out important hub genes. Finally, the Boxplot and Survival Analysis of the hub genes in various cancers were performed by GEPIA. Results. 755 genes related to obesity and inflammation and 38 genes related to acupuncture and inflammation were identified, and 24 coexpressed genes related to obesity, inflammation, and acupuncture were extracted from the Venn diagram. Eight hub genes including interleukin-6 (IL-6), interleukin-10 (IL-10), Toll-like receptor 4 (TLR4), signal transduction and transcriptional activation factor 3 (STAT3), C-X-C motif chemokine 10 (CXCL10), interleukin-17A (IL-17A), prostaglandin peroxide synthesis-2 (PTGS2), signal transistors, and transcriptional activation factor 6 (STAT6) were identified by gene ontology (GO), Kyoto Encyclopedia of Genes (KEGG), and PPI network analysis. Among them, IL-6 is suggested to play an essential role in the treatment of obesity and inflammation by acupuncture, and IL-6 was significant in both Boxplot and Survival Analysis of pancreatic cancer (PAAD). Therefore, in this study, the core gene, IL-6 was used as the breakthrough point to explore the possible mechanism of acupuncture in treating obesity and pancreatic cancer by regulating IL-6. Conclusion. (1) Acupuncture can regulate the expression of IL-6 through the TLR4/nuclear factor-κB (NF-κB) pathway, thereby alleviating inflammation, which can be used as a potential strategy for the treatment of obesity. (2) IL-6/STAT3 is closely related to the occurrence, development, and metastasis of pancreatic cancer. Acupuncture affecting pancreatic cancer through TLR4/NF-κB/IL-6/STAT3 pathway may be a potential method for the treatment of pancreatic cancer.

This letter presents a broadband microstrip-to-microstrip vertical transition. Basically, the transition is based on broadside coupling between the upper and lower microstrip patches through a wide slot etched on the ground plane. In order to enhance bandwidth of the transition, a patch introducing a half wavelength resonance into the passband is added on the ground plane. A demonstrator transition has been designed, fabricated and measured. Results show that a frequency range of 2.8 to 8.5 GHz (referred to return loss of 10 dB) is obtained.

Several through-silicon-substrate-via-holes used in microwave circuits are analyzed. The silicon via-holes have been fabricated by inductively coupled plasma (ICP) process. Using via-holes for microstrip transmission lines, a micromachined Ku-band interdigital filter has been designed, fabricated, and tested. It achieved an insertion loss of −2.4 dB, and a 3 dB fractional bandwidth of 8%. This filter has the advantages of small sizes and relatively outstanding RF performance.

A 3-bit microelectromechanical system (MEMS) digital attenuator is designed with 0–20 GHz bandwidth. The attenuation ranges from 0 to 35 dB with 5 dB step. The attenuator, with the coplanar waveguide (CPW), is implemented by surface sacrificial layer technology. The DC-contact MEMS switches with three contact dimples are symmetrically placed around the T type resistor network, making the switches minimum in number and the structure compact. Through the lumped parameter method, the attenuator has good terminal matches in different attenuation states. The test results show that eight different attenuation states are realized within 0–20 GHz. The attenuation deviation is less than ±5%, the insertion loss is less than 1.7 dB and the voltage standing wave rations is less than 1.4 under most of the attenuation states. With the MEMS switches and CPW being adopted, the attenuator has the advantages of higher linearity, lower insertion loss and power consumption. The chip size is about 3.2 mm2 including the pad.

In order to improve the temperature stability of DC-contact RF MEMS switch, a thermal buckle-beam structure is implemented. The stability of the switch pull-in voltage versus temperature is not only improved, but also the impact of stress and stress gradient on the drive voltage is suppressed. Test results show that the switch pull-in voltage is less sensitive to temperature between -20 °C and 100 °C. The variable rate of pull-in voltage to temperature is about -120 mV/°C. The RF performance of the switch is stable, and the isolation is almost independent of temperature. After being annealed at 280 °C for 12 hours, our switch samples, which are suitable for packaging, have less than 1.5% change in the rate of pull-in voltage.

Cantilever beam DC-contact RF MEMS switches, with bias electrodes physically insulated from the RF/microwave transmission line (t-line), have been developed for broadband communication system applications. The paper presents the design, optimization and equivalent circuit model for the MEMS switches. The beam is composed of multilayer thin films formed by a slightly tensile stressed dielectric and metal layer. A MEMS switch sample has been fabricated based on a low temperature surface micromachining process. On-wafer measurement results are as follows: insertion loss less than 0.8 dB; isolation more than 26 dB at 0.1-26 GHz; applied voltage 30-80 V.

A 4-bit digital MEMS phase shifter, based on RF MEMS series switches and switched-line design, is presented. The phase shifter is fabricated on a 360 ­ m-thick silicon substrate, and the chip size is smaller than 5 h 8 mm 2 . The simulation performance of 16 phase states shows that at X-band the worst insertion phase deviation is 8 degree from the desired value, the insertion loss is less than -2.0dB and the VSWR is less than 1.8. Keywords: MEMS phase shifter, switched-line 1. INTRODUCTION Since the first wideband true-time delay MEMS phase shifter was developed by N. S. Barker in 1998 A , many MEMS phase shiftersAuD have been reported. Most of them use RF MEMS switches in a distributed MEMS transmission lines (DMTL) periodically. The DMTL is operated as a phase shifter by applying a single analog control voltage between the center conductor and ground plane of the CPW line. It has the effect of pulling the MEMS bridges (or beam, cantilever, diaphragm) closer to the center line creasing the phase velocity. It is this change in phase velocity that produces the true-time delay phase shifter. Its typical configuration is showed in Fig.1.This configuration is suitable for the analogue control device, but it is difficulty to develop multi-bit digital phase shifters. For example, more than 20 RF MEMS switches are needed for a 4- bit digital phase shifter.

This paper describes a novel monolithic switchable filter covering a bandpass frequency of 12–16 GHz at the Ku-band on a silicon substrate. The filter structure is based on parallel-coupled half-wavelength resonator topologies and microelectromechanical system-tunable resonators designed by placing ohmic switches at the open ends of the microstrip resonators. A wideband coplanar waveguide is designed for microstrip transition without via holes during wafer testing. The measured results show a minimum insertion loss of 3.6 dB, a return loss better than 15 dB, a 10.2% fractional bandwidth and a 14.2% tuning range from 13 to 15 GHz. The fabricated filter has a chip area of 15.1 mm × 3 mm and has achieved skirt slopes of over 30 dB GHz−1.