Preparation of a Carbon Doped Tissue-Mimicking Material with High Dielectric Properties for Microwave Imaging Application.

In this paper, the oil-in-gelatin based tissue-mimicking materials (TMMs) doped with carbon based materials including carbon nanotube, graphene ink or lignin were prepared. The volume percent for gelatin based mixtures and oil based mixtures were both around 50%, and the doping amounts were 2 wt %, 4 wt %, and 6 wt %. The effect of doping material and amount on the microwave dielectric properties including dielectric constant and conductivity were investigated over an ultra-wide frequency range from 2 GHz to 20 GHz.

Design, manufacture and in-vitro evaluation of a new microvascular anastomotic device.

Introduction: Many microvascular anastomoses have been proposed for use with physical assisted methods, such as cuff, ring-pin, stapler, clip to the anastomose blood vessel. The ring-pin type anastomotic device (e.g.

Design optimisation and experimental evaluation of dorsal double plating fixation for distal radius fracture.

This study determines the relative effects of changes in osteoporosis condition, plate/screw design factors (plate angle/length/width/thickness and screw diameter) and fixation methods (screw number and screw length) on the biomechanical response of dorsal double plating (DDP) fixation at a distal radius fracture to determine the optimal design and evaluate its biomechanical strength using the dynamic fatigue test. Eighteen CAD and finite element (FE) models corresponding to a Taguchi L18 array were constructed to perform numerical simulations to simulate the mechanical responses of a DDP fixed in a simply distal radius fracture bone. The Taguchi method was employed to determine the significance of each design factor in controlling bone/plate/screw stress and distal fragment displacement under axial (100 N), bending (1 N m) and torsion (1 N m) loads.

Visibility enhancement of common bile duct for laparoscopic cholecystectomy by vivid fiber-optic indication: a porcine experiment trial.

Bile duct injury (BDI) is the most serious iatrogenic complication during laparoscopic cholecystectomy (LC) and occurs easily in inexperienced surgeons since the position of common bile duct (CBD) and its related ductal junctions are hard to precisely identify in the hepatic anatomy during surgery. BDI can be devastating, leading to chronic morbidity, high mortality, and prolonged hospitalization. In addition, it is the most frequent injury resulting in litigation and the most likely injury associated with a successful medical malpractice claim against surgeons.

Determination of azimuthal anchoring strength in twisted nematic liquid crystal cells using heterodyne polarimeter.

Two external-field-free methods are presented for measuring the azimuthal anchoring strength in twisted nematic liquid crystal (TNLC) cells. For asymmetrical TNLC samples, the twist angle is derived from the phase of the detected signal in a phase-sensitive heterodyne polarimeter and is then used to calculate the weak anchoring strength directly. The measurement resolution which is found to be about 0.

Measurement of linear birefringence and diattenuation properties of optical samples using polarimeter and Stokes parameters.

A technique is proposed for measuring the linear birefringence and linear diattenuation of an optical sample using a polarimeter. In the proposed approach, the principal axis angle (alpha), phase retardance (beta), diattenuation axis angle (thetad), and diattenuation (D) are derived using an analytical model based on the Mueller matrix formulation and the Stokes parameters. The dynamic measurement ranges of the four parameters are shown to be alpha = 0 approximately 180 degrees, beta = 0 approximately 180 degrees, theta(d) = 0 approximately 180 degrees, and D = 0 approximately 1, respectively.

Full-field and full-range sequential measurement of the slow axis angle and phase retardation of linear birefringent materials.

A method is proposed for obtaining full-range sequential measurements of the slow axis angle and phase retardation of linear birefringent materials (LBMs) using a full-field heterodyne interferometer with a charge-coupled device (CCD) camera and an image processing algorithm based on a three-frame integrating-bucket method. The dynamic ranges of the principal axis and phase retardation measurements extend from 0 degrees to 180 degrees and from 0 degrees to 360 degrees , respectively. The proposed method not only enables full-range measurements of the slow axis angle to be obtained, but also allows a decision to be made as to whether the principal axis labeled by the manufacturer is the slow axis or the fast axis.

Full-field heterodyne polariscope with an image signal processing method for principal axis and phase retardation measurements.

We develop a heterodyne polariscope for measuring the two-dimensional principal axis and phase retardation in a linear birefringence material using novel three-frame and two-frame integrating-bucket methods and a CCD. By using a complex programmable logic device to provide an external trigger to the CCD, integrating buckets with multiple frames are achieved. The advantages of the proposed three-frame and two-frame integrating-bucket methods include a simpler signal processing algorithm based on fewer frames and the elimination of flyback error caused by a sawtooth modulation signal at higher frequencies.