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Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver. It most commonly metastasizes haematogenously to the lungs and bones, less commonly via lymphatics to lymph nodes. However, metastasis to the parapharyngeal space has yet to be reported. This is the first clinical report of the treatment of parapharyngeal metastasis from HCC. The case of a 46-year-old man who was found to have a parapharyngeal soft tissue mass during routine follow-up 12 years post deceased-donor liver transplantation for hepatitis B-related HCC is reported here. This was investigated and diagnosed to be metastatic HCC. He underwent excision of the parapharyngeal metastasis, followed by adjuvant radiotherapy. Parapharyngeal metastasis is a rare occurrence in HCC. It is important to be cognizant of the possibility of disease spread to this location in order to ensure early detection and treatment. Surgical excision with adjuvant radiotherapy should be considered to achieve disease control.

Membranes of chitosan-based proton conductor polymer electrolyte were prepared by dissolving chitosan powder, ammonium nitrate (NH 4 NO 3 ) salt and ethylene carbonate (EC) plasticizer in acetic acid solution. The temperature dependence of the chitosan-based membrane system was found to obey the Arrhenius relationship. The sample with the highest conductance, 18 wt.% CA + 12 wt.% NH 4 NO 3 + 70 wt.% EC (CA40N70E), also possesses the lowest activation energy. From linear sweep voltammetry (LSV) results, the membrane is electrochemically stable at a potential of 1.6–1.8 V and a temperature of 298–353 K. The cells were fabricated using zinc powder (Zn) + zinc sulfate heptahydrate (ZnSO 4 ·7H 2 O) + acetylene black (AB) + polytetrafluoroethylene (PTFE)|CA40N70E|manganese (IV) oxide (MnO 2 ) + AB + PTFE. The open circuit voltages of the cells are decreases as temperature increases, the same trend as that obtained by LSV. The cell performance is excellent at 333 K, with discharge capacity of 42.7 mAh, internal resistance of 16.8 Ω, maximum power density of 14.6 mW cm −2 and a short-circuit current density of 31.0 mA cm −2 . However, at temperatures above 333 K, decomposition of the membrane degraded the electrochemical properties of the cells.

The strategy for minimising the flicker noise in the folded-cascode amplifier topology is presented and the inter-relationship of design parameters for optimum design is described. The HSPICE simulation results correlate very well with the theory and validate the design methodology. The proposed solution offers good tradeoff on the conflicting performance parameters such as noise, silicon area, bandwidth and power consumption. It will be useful for the analytic model in CAD design optimisation and allows fast computation or first-order hand analysis on noise evaluation.

Powder metallurgy based on cold isostatic pressing, vacuum sintering and hot isostatic pressing (HIP) reveals the possibilities of mass producing critical parts in near net shape. The multi-stage process consists of: (i) cold isostatic compaction to a green perform; (ii) supersolidus vacuum sintering of compact to more than 90% density; and (iii) final consolidation via hot isostatic pressing to densify the preform. Three-point flexural tests were carried out on the sintered and HIPped specimens. Microstructure and porosity evaluations were conducted using scanning electron microscopy and image analysis.

Several lossless current sensing techniques have been proposed in literatures and adopted by the industries in recent years. However, none of these solutions have addressed the issue of uniform sense accuracy. In this paper, an in-depth analysis of the lossless current sensing technique implemented in a dc-dc buck converter is presented. The compensation techniques for achieving a uniform sense-ratio are discussed and analyzed using two different current sense circuit topologies. The sense circuits are designed using the AMS 0.35 um, 4 metals, double poly CMOS process. Using the same technology and operating under the same electrical conditions, the simulation results show that the proposed sense circuits achieved a maximum sense accuracy of 99%, compared to 95% achieved using the conventional approach.

The performances of Variable Gain Amplifier (VGA) using 3 different composite transistors are studied. The first Simple Composite Transistor [1] requires high power consumption. The second Composite Transistor uses Vds compensation technique to lower the power consumption level. Their performances are compared with a third Low Power Composite Transistor [2].

Clearly, automatic recognition in large face populations will require many measurements. There have been few approaches which aim to generate such extended feature vectors. One approach considered combining several different sets, including feature descriptions and transform components, with apparent advantages accrued by the orthogonality of the measurements. More robust measures have included a new technique for eye location which employs concentricity using only few parameters and requiring little a priori information concerning a face's location. Further, a dual contour employing global energy minimisation, again requires few parameters to provide measurements describing the face's boundary, again aimed at inclusion within an extended feature vector. Naturally, we seek to capitalise on minimal statistical correlation to improve recognition capability. To this end, we consider further the analysis of potential advantages of orthogonality, and show how this can indeed improve recognition capability. Accordingly, there is much research potential in extending the feature vector for automatic face recognition: there are rich avenues for future research in generation and combination of feature vectors for use in large face populations.

This paper presents a software system for implementing synthesized digital designs using VHDL so that the designs can be accepted by existing CAD systems to achieve low-level verification such as delay analysis and logic simulation as well as layout realization in various technologies.

Employing multi-stage sigma–delta modulators has provided an effective means of eliminating stability problems while achieving highresolution analog-to-digital conversion. However, component matching has become more stringent than a single-stage modulator. Mismatches cause loss in the modulators signal-to-noise ratio (SNR), but to a certain class of multi- stage modulators, discontinuity is also apparent in its SNR characteristics. This class of modulators employs a first-order modulator in its first stage. The discontinuity is caused by the nonlinearity of a first-order modulator’s noise, which is related to the minimum input requirement for the first-order modulator. This brief includes the formulation of the firstorder modulator’s minimum amplitude, nonlinear characteristics, and its effect on multi-stage modulators. Published version

A Dual Mode Electric Transportation (DMET) system is under development in which energy is electromagnetically transferred from a powered roadway to moving vehicles without mechanical contact. Energy from the roadway can be used for high-speed, long range travel, and for replenishing energy stored in the vehicle in batteries or flywheels. The stored energy is then availble for short-range travel off the powered highway network. A static prototype of the inductive power coupling has been built and tested. Power transfer was demonstrated to conform to the models developed in an earlier phase of the project. The prototype was used to study the power of coupling mechanism and resulting design improvements are incorporated. Tests of properties of the coupling included electrical characterization of the prototype equipment, measurements of the magnetic force between power source and pickup, measurements of coupled power versus pickup airgap and offset, measurements of magnetic flux in and around the prototype, and measurements of thermal effects induced by coupled power. The tests resulted in several design improvements which were incorporated into the coupling design. Results from the power coupling study were used to aid in the design of the dynamic prototype, in which a fifty meter powered test track and electric car with power pickup will be tested.

A Dual Mode Electric Transportation (DMET) system is under development in which energy is electromagnetically transferred from a powered roadway to moving vehicles. Energy from the roadway can be used for high-speed, long-range travel and for replenishing energy stored in the vehicle in batteries or flywheels. The stored energy is then available for short-range travel off the powered highway network. The power coupling between roadway and vehicle is functionally similar to a transformer. A source is embedded in the roadway flush with the surface. When the vehicle's pickup is suspended over the source, energy is magnetically coupled through the clearance air gap between pickup and roadway source. The electromagnetic coupling mechanism has been extensively studied through computer models, circuit analyses and by tests of a full-size physical prototype. The results of these tests are described.

This paper presents the new circuit topologies of single-ended and differential CMOS squarer circuits, which rely on transistors operating in non-saturation region. It exploits the bulk compensation technique to eliminate the gamma-dependent constant in the gain definition equation, hence reducing the gain and circuit sensitivity due to process variations. Second-order analysis on the circuits demonstrates that the dominant non-ideal effects are due to mobility degradation and mismatch in devices. The theoretical prediction correlates very well with the measurement results. The experiment shows that the squarer circuit performs a good squaring function. For differential test input signal with 500 mVpp at 1 kHz, the fundamental and odd harmonics are less than 50 dB relative to the squared signal.