Preparation and characterization of C/Ni-PTFE electrode using Ni-PTFE composite plating for alkaline fuel cells

Graphite particles (80 μm) and PTFE particles (40 μm) were coated with Ni (18-50 wt.%) and PTFE fine particles (0.3 μm; 8 wt.%) via electroless Ni-PTFE composite plating. The conductivity of Ni-PTFE plated graphite (C/Ni-PTFE) and PTFE (PTFE/Ni-PTFE) particles increased with the Ni content. At 35 wt.% Ni content, the conductivity (300 Sm⁻¹) of C/Ni-PTFE particles was about 2 times higher than that of PTFE/Ni-PTFE particles. The particles were pressed into plates under a pressure of 10-500 kg cm⁻² and the plates were then subjected to heat treatment at 350 °C. The surface of C/Ni-PTFE plates contained infinitely many gaps of 0.01-20 μm; these gaps are useful as a pathway for reacting gases. The conductivities in a direction perpendicular and parallel to the C/Ni-PTFE plates were respectively about 3.5 times (510 Sm⁻¹) and 16 times (48 × 10³ Sm⁻¹) higher than those of the PTFE/Ni-PTFE plates. Furthermore, the total pore volume (0.145 cm³ g⁻¹) of C/Ni-PTFE plates was higher than that of PTFE/Ni-PTFE plates, which improved the gas permeability of the former. The current density (84 mA cm⁻² at 0.3 V) of C/Ni-PTFE electrode was about 2 times higher than that of PTFE/Ni-PTFE electrode. This increase in the current density might be attributed to the improvement in the total conductivity and gas permeability of C/Ni-PTFE electrode.     

Interlaboratory validation of quantitative duplex real-time PCR method for screening analysis of genetically modified maize

To reduce the cost and time required to routinely perform the genetically modified organism (GMO) test, we developed a duplex quantitative real-time PCR method for a screening analysis simultaneously targeting an event-specific segment for GA21 and Cauliflower Mosaic Virus 35S promoter (P35S) segment [Oguchi et al., J. Food Hyg. Soc. Japan, 50, 117-125 (2009)]. To confirm the validity of the method, an interlaboratory collaborative study was conducted. In the collaborative study, conversion factors (Cfs), which are required to calculate the GMO amount (%), were first determined for two real-time PCR instruments, the ABI PRISM 7900HT and the ABI PRISM 7500. A blind test was then conducted. The limit of quantitation for both GA21 and P35S was estimated to be 0.5% or less. The trueness and precision were evaluated as the bias and reproducibility of the relative standard deviation (RSD(R)). The determined bias and RSD(R) were each less than 25%. We believe the developed method would be useful for the practical screening analysis of GM maize.     

An integrated switched-capacitor signal processing design system

A CAD system integrating switched-capacitor network function synthesis, circuit synthesis, and layout is presented. The tool addresses the design of programmable gain, cosine, interpolation, and arbitrary transfer functions in addition to canonical filter structures. Amplifier design is based on numerical optimization of highly accurate analytic models derived with the aid of symbolic-mathematics-based model development aids. The physical design of the filter is created by a general-purpose switched-capacitor circuit synthesizer. The tool makes it possible to synthesize a complete switched-capacitor signal path with full handcrafted quality in a single day. Examples taken from actual IC designs illustrate the utility and accuracy of the various functions     

Development of non-iodized oily agent in targeting chemoembolization for hepatocellular carcinoma

The purpose of this study was to evaluate a new oily agent in targeting chemoembilization for hepatocellular carcinoma. The oily preparation was made by mixing non-iodinated poppy seed oil and a thickener to obtain the same viscosity as Lipiodol. The oily preparation and Lipiodol were compared by injecting them into the hepatic artery of rabbits inoculated with VX 2 carcinoma in their liver. On the CT scan following intra-arterial injection, tumors were visibly stained in the non-iodinated preparation group, whereas the Lipiodol group was not evaluable because of excessively high attenuation. The non-iodinated oily preparation was concluded to be of clinical significance.     

Numerical accuracy on Fm(z) for molecular integral calculations

Large-scale SCF calculations require more accurate numerical results. We investigated numerical accuracy on various F_m(z) evaluation methods. We found that the polynomial of z, which are often used for the Taylor series expansion and the Chebyshev approximation in molecular orbital programs, contains unexpectedly large numerical errors even if a polynomial degree is cubic. The numerical accuracy is allowable for small molecules, but may be insufficient for large molecules. On the other hand, the polynomial of δ, which requires only one more calculation step than that of z, maintains sufficient numerical accuracy because round-off errors are hardly propagated in the polynomial of δ.     

Design and performance of a novel automatic fiber line testingsystem with OTDR for optical subscriber loops

This paper proposes architecture for a novel automatic fiber line testing system with an optical time-domain reflectometer (OTDR) and describes the system requirements, the design method, and the system evaluation. The results of a trial on a manufactured system and an evaluation of its characteristics are presented with evidence that an in-service optical fiber can be tested with no degradation in communication quality and the desired measurement accuracy and system component characteristics can be realized. In addition, it is confirmed that a failure between an optical fiber cable and a digital service unit (DSU) can be identified with 100% accuracy     

Markedly increased accumulation of Tc-99m DTPA in a patient with neurofibromatosis

A key issue in nucleic acid-based assays related to infectious disease testing and genetic testing is the sample preparation. This has to be convenient, efficient and suitable for automation. We describe a new method based on the use of glass magnetic particles. The steps involved are the lysis of bacterial cells and viral particles by chaotropic salts, binding of released nucleic acids to the magnetic glass particles, the removal of inhibitors and the release of purified nucleic acids ready for PCR amplification. The method fulfills most of the requirements for sample preparation such as sensitivity, universality and suitability for automation.     

Change in fibrinolytic activity as a parameter for assessing local mechanical stimulation during physical exercise

The influences of mechanical force during physical exercise on blood coagulation and fibrinolysis were investigated and the effects of sports equipment, especially shoes were also examined. As an experimental model, local mechanical vibration was applied to the palm of the hand. General coagulation parameters did not change, but fibrinolytic activity was elevated due to the tissue plasminogen activator (t-PA) released from vascular endothelial cells stimulated by vibration. The influence of mechanical stimulation by repeated side-jumping with bare feet was examined on the sole of the foot. As with t-PA, the von Willebrand Factor antigen (vWF:Ag) derived from vascular endothelial cells also tended to increase, but not as much as when wearing sports shoes. Sports shoes protected the blood vessels of the feet from damage by mechanical force during physical exercise. Changes in fibrinolytic activity and t-PA could be useful for assessing local mechanical stimulation during physical exercise and also as indexes for the development of new sports equipment and its improvement.     

Technetium-99m-MIBI and thallium-201 scintigraphy of primary lung cancer

We evaluated the usefulness of 99mTc-MIBI scintigraphy in primary lung cancer in comparison with 201Tl-chloride scintigraphy. METHODS: There were 45 patients with primary lung cancer. All patients underwent dual-isotope imaging with 201Tl-chloride and 99mTc-MIBI. Regions of interest were placed over the tumors (T) and contralateral normal lung tissue (N) on one coronal view in the SPECT, and T/N ratio and retention index were calculated. RESULTS: The positive rate was 98% in both the early and delayed images for 201Tl-chloride and 96% in the early and 89% in the delayed image for 99mTc-MIBI. Both early and delayed T/N ratios for 201Tl-chloride were higher than those for 99mTc-MIBI. There was no significant correlation between T/N ratio and histological type of tumor in both images. However, in both images, there was a tendency for the early and delayed ratios to increase as the tumor diameter became larger. The retention index of 201Tl-chloride was higher than that of 99mTc-MIBI. There were no significant differences in the retention index with respect to the histological type and tumor size. CONCLUSION: The results of this preliminary clinical study suggest that 99mTl-MIBI can depict primary lung cancer similar to 201Tl-chloride. However, T/N ratio and retention index of 99mTc-MIBI in the tumor areas are significantly lower compared with those of 201Tl-chloride.     

Density functional calculations on agostic ethyl-Ti (IV) complexes

First principles, density functional theory embodied in the DMol program has been applied to agostic ethyl-Ti-complexes, including the dmpe complex, [Ti(-CH₂CH₃)C1₃(dmpe)], where DMPE=(Me₂PCH₂)₂ and its model complex, [Ti(−CH₂CH₃)Cl₃(PH₃)₂]. The ethyl moiety of the complexes can adopt two limiting conformations, staggered and eclipsed. In the model complex, [Ti(−CH₂CH₃)C1₃(PH₃)₂], both conformers are found to form agostic structures upon geometry optimization subject to Cs symmetry constraint, with the agostic eclipsed structure being the lower in energy. Full geometry optimization of the dmpe complex, [Ti(−CH₂CH₃)C1₃(dmpe)], yields an agostic structure with geometrical features similar to those measured by single crystal X-ray analysis. It is shown that the HOMO orbital contributes substantially to the agostic bonding.