Postoperative adhesions remain a significant complication of abdominal surgery although the wide variety of physical barriers has been developed to reduce the incidence of adhesion. In this study, the bilayered composite membrane formed by the association of a methoxy poly (ethylene glycol)-poly (L-lactide-co-glycolide) (mPEG-PLGA) film and a crosslinked collagen-hyaluronic acid (Col-HA) membrane with fibronectin (FN) coating was prepared for promoting wound healing and providing tissue adhesion resistance simultaneously. In vitro adhesion test revealed that fibroblasts attached better on Col-HA membrane compared to those on mPEG-PLGA film, PLGA film or Interceed (oxidized cellulose) while mPEG-PLGA film had the lowest cell adhesive property. In confocal microscopic observation, the actin filaments were significantly further polymerized when 50 or 100 microg/cm(3) fibronectin was incorporated on the COL-HA membranes. After 7-day culture, fibroblasts penetrated throughout the Col-HA-FN network and the cell density increased whereas very few cells were found attached on the surface of the mPEG-PLGA film. In vivo evaluation test showed that the composite membrane could remain during the critical period of peritoneal healing and did not provoke any inflammation or adverse tissue reaction.

Carbon nanotubes (CNTs) have remarkable mechanical strength, electrical conductivity, and thermal conductivity in spite of low density. Recently, CNT / epoxy composite have been widely investigated in terms of fabrication process and material characterizations. However, there have been few previous studies on B-stage film type CNT / epoxy composites for electronic packaging applications. B-stage film type CNT / epoxy composite films were fabricated and their properties were characterized for electronic packaging applications. The most important issue on fabrication on B-stage epoxy based films were uniform dispersion of CNTs in an epoxy resin. In this study, using optimized dispersion process, CNT / epoxy films were coated on a releasing film and subsequently dried by the comma roll coating method. Curing behavior of B-stage films, mechanical properties and electrical properties of fully cured films were characterized as a function of CNT contents. According to experimental results, CNTs lowered the curing activation energy of epoxy resin and increased electrical conductivity of epoxy resin.

No abstract

New low temperature, low cost, small size packaging technology of novel bulk-micromachined MEMS sensor for mobile applications was developed. The sensor was fabricated with the bulk-micromachining process of SOI substrates and composed with a proof mass, membrane and electrodes for capacitance sensing. The sensor device was capped with very thin (130um-thickness) top and bottom silicon cap wafers which have a 80um-depth cavity. Top and bottom cap wafers were bonded with the sensor wafer with a low temperature curing polymer adhesive lower than 200°C. It is needed that the low temperature packaging technology and the passivation of top and bottom sides of the sensor for keeping the sensor performances and preventing stiction of the proof-mass during the molding processes. After bonding the three substrates, the top cap silicon was dry etched to expose bonding pads for the signal interconnection. The ASIC chip was polished to 75um-thickness, diced and bonded on a half-etched 200um-thick lead-frame with a DAF. The diced wafer-level-capped sensor was stacked on the ASIC, wire bonding was accomplished between the sensor and the ASIC, and the ASIC and the lead-frame and finally transfer molding process was done. The developed package is 24-leads QFN and the dimension is 4.0mm×4.0mm×1.1/1.2mm.

Unmanned aerial vehicles (UAVs), particularly Drone-Quadrotors, have gained immense popularity and attracted significant attention. Stability control development and research have emerged as prominent areas of interest among researchers. This study focuses on the design of a controller for a series of quadrotor UAVs with the goal of achieving optimal control while ensuring stability and reaching the desired setpoint. Additionally, our investigation reveals that for miniature UAVs, the internal force acting on the quadrotor is comparatively negligible when compared to the force generated by the control signal. As a result, the non-holonomic nature of the system can be disregarded in the kinetic model of the miniature UAV, while still maintaining satisfactory kinetic performance with the designed controller. The research findings are simulated, compared, and presented using Matlab/Simulink, demonstrating the high efficiency and reliability of the proposed controller.