A new polymer microlens with variable focusing properties is designed and fabricated. The microlens consists of a thin diaphragm with 3D convex lens, chamber and microchannel, which are made of polydimethyl-siloxane (PDMS). A novel fabrication approach has been developed to cast the PDMS microlens film using a PDMS mold. The elastomeric PDMS microlens film acts as a diaphragm. The flexible PDMS microlens and diaphragm are integrated on a microfluidic chip. By varying the pressure in the microfluidic chamber, which produces a shift in the microlens' focal plane, this can change the back focal length of lens. The new fabrication method provides easy fabrication, low-cost production and precise dimension control. Measurement with an atomic force microscope reveals that the surface roughness of the lens is 18.6 nm, and real-time contact-angle measurements show the back focus length tuning range is from 3.8 mm to 10.6 mm. The variable focal length of the microlens is critical to increase the efficiency of the light detection in optical or biophotonic applications. In this paper, the fabrication processing, mechanical and optical property testing, and simulation results are presented in detail.

Hard magnetic materials with high remnant magnetic moment, Mr, have unique advantages that can achieve bi-directional (push–pull) movement in an external magnetic field. This paper presents the results on the fabrication and testing of novel composite elastic permanent magnet films. The microsize hard barium ferrite powder, NdFeB powder, and different silicone elastomers have been used to fabricate various large elongation hard magnetic films. Three different fabrication methods, screen-coating processing, moulding processing and squeegee-coating processing, have been investigated, and the squeegee-coating process was proven to be the most successful method. The uniform composite elastic permanent magnet films range from 40 µm to 216 µm in thickness have been successfully fabricated. These films were then magnetized in the thickness direction after fabrication. They exhibited permanent magnet behaviour; for instance, the film (0.640 mm3 in volume) made of polydimethyl siloxane (PDMS) and hard barium ferrite powders is measured to give a coercive force, Hc, of 3.24 × 105 A m−1 and Mr of 1.023 × 10−5 A m2, and the film (0.504 mm3 in volume) made of PDMS and NdFeB powders gives 1.55 × 105 A m−1 Hc and 8.081 × 10−5 A m2 Mr. These composite elastic permanent magnet films' mechanical properties, like Young's modulus and deflection force, have been evaluated. To validate the films' Young's modulus, a finite-element computer simulation (ANSYS®) is used and one film is chosen whose Young's modulus (16.60 MPa) is confirmed by the simulation results with ANSYS®. The large elongation composite elastic permanent magnet film provides an excellent diaphragm material, which plays an important role in the micropump or valve. The movement of the 126 µm thick film with 4.5 mm diameter made of PDMS and NdFeB powders has been tested in a 0.21 Tesla external magnetic field. It was proven to have large deflection of 125 µm.

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This article experimentally studies the application of vanadium dioxide (VO 2 ) thin film for tunable inductor design. VO 2 's temperature-dependent conductivity is used for implementing a tunable inductor using VO 2 as the control material. Two different configurations of inductors are designed. One design uses a short VO 2 bar as a circuit switch and the other uses VO 2 to replace the full spiral coil inductor. The frequency range in the experiments is 0.3-2 GHz. Experimental results show a 32% tuning range (1-0.68 nH) through applied temperature variation (25-1008C) in the devices. These results are matched by a working circuit p model. ABSTRACT:In this work, a dual bands omnidirectional monopole antenna is proposed. A planer Y-shaped patch is loaded on the top of the surface and a slot is loaded on the ground plane to obtained broadband. Rogers RT/duroid5880(tm) substrate is used with dielectric constant 2.2 and loss tangent 0.0009. The results of the proposed antenna for the variation of width and length of the ground plane are investigated. Two licensed free frequency bands at 2.4 GHz and 5.8 GHz are obtained for WiFi and Bluetooth application. The measured frequency bands of 2.3-2.52 GHz at 2.4 GHz and 4.22-10.30 GHz with two resonant frequencies at 4.96 and 8.36 GHz are obtained. The peak antenna gain of 4.6 dBi at 2.4 GHz is achieved. Simulation has been done using MOM base Ansoft designer software.

As one of the most serious microvascular complications of diabetes and a major cause of end stage renal disease, diabetic nephropathy (DN) is calling for effective treatment strategies. Here, we provide evidence that hyperglycemia can induce proliferation and decreasing apoptosis of mesangial cells (MCs) and subsequent renal dysfunction by up-regulating cellular FLICE-inhibitory protein (cFLIP). Treatment with emodin significantly turns down the accelerated cell cycle and proliferation of MCs cultured in high glucose (HG) via inhibiting cFLIP. In vitro, knockdown of cFLIP can arrest cell cycle and accelerate cell death by activating caspase-8, caspase-3 and caspase-9, and down-regulate proliferating cell nuclear antigen (PCNA). Our results also suggest that emodin regulates cFLIP expression in transcriptional level. Importantly, emodin lessens proteinuria and fibronectin expression in early-stage of streptozotocin (STZ)-induced diabetic rats. These findings demonstrate that emodin represent a promising strategy to prevent renal dysfunction in early-stage of diabetes mellitus.