Hydrothermal Corrosion of Alumina Ceramics

The corrosion behavior and strength degradation of alumina ceramics with 99%, 99.9%, and 99.99% Al₂O₃ were studied in water at 300°C and 8.6 MPa for 1 to 10 d. The weight loss in alumina ceramics was mainly attributed to the dissolution of SiO₂ and Na₂O grain-boundary impurities. Intergranular corrosion proceeded in the alumina ceramics by preferential attack at the grain boundaries. The extent of the strength reduction for corroded alumina ceramics was related to the impurity level in the alumina ceramics.     

A bag carrier for continuous intravenous hyperalimentation

We designed a new bag-carrier device system for continuous intravenous hyperalimentation. The patient carries it on his shoulder and can both walk up and down stairs and go out. The use of this device is simple and easy, and was found to increase the patient's opportunity to engage in physical activity.     

Electrical Properties of 1.7-MeV-Electron-Irradiated Sulfur-Doped GaP

The electrical properties of 1.7-MeV-electron-irradiated sulfur (S)-doped GaP were studied by using Hall effect and resistivity measurements. It was found that the concentration of S donors decreased and the deep acceptors were introduced by 1.7-MeV electron irradiation. The decrease of the concentration of S donors could be understood by considering the formation of a complex center of radiation-produced defects with S. A complex center acted as a deep acceptor and recovered in the stage centered at 150°C anneal. The introduction rate of this center was ~2.1 cm-1. From the isothermal annealing experiments, it was found that the recovery for this center approximately obeyed first-order kinetics and its activation energy was ~1.7 eV. Furthermore, another complex center involving S, which was a non-compensating defect in n-type GaP, was introduced. This center was seemed to be a deep donor.     

Impact of Key Circuit Parameters on Signal-to-Noise Ratio Characteristics for the Radio Frequency Single-Electron Transistors

Hybrid simulation was performed to analyze the response of the real-time reflection-type radio frequency single-electron transistor (RF-SET) measurement system. A compact and physically-based analytical SET model, which was validated with a Monte Carlo simulator, was used to simulate the SET characteristics, while SPICE equivalent circuits were implemented to simulate all other components of the RF-SET measurement system. The impact of various key parameters on the RF-SET response was demonstrated for a carrier frequency much less than I/e ( is the typical current through the SET). It was revealed that an inevitable feed-through loss between the tank circuit and the cryogenic amplifier, and high-frequency parasitics of the inductor degrade the RF-SET performance significantly. As such, they have to be optimized to experimentally realize the shot-noise-limited charge sensitivity.     

Signal control by successive updating of control parameters based on prediction of traffic flow

In traditional coordinated traffic signal control on an urban road network, the following two problems occur. First, the conventional method involves a time lag between traffic measurement and signal control. Second, an abrupt switching of control parameters throws the traffic flow into disorder. This paper proposes a new approach to avoid these problems. We increase the frequency of switching. The control parameters are switched as frequently as every two cycles. At the time of switching, minor variations of the ongoing plan are generated. For each variation of plan, traffic delay at each intersection is predicted based on measured traffic data at upstream detectors. Then the plan minimizing the delay is chosen to be the control parameters in the next cycle. In order to evaluate the validity of this approach, experiments were carried out using a traffic simulator. The experiments indicate that the proposed method reduces the queue length significantly, compared with the conventional method. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(3): 49–57, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20391     

Isolated Schwann cells can synthesize the basement membrane in vivo

The purpose of the present study is to examine whether isolated Schwann cells that are not in contact with axons can synthesize the basement membrane in vivo. Schwann cells obtained from sciatic nerve of neonate Wistar rats were prepared in culture, harvested, and mixed with collagen matrix. The silicone tube filled with the collagen matrix containing Schwann cells was closed by a Millipore membrane at both ends to isolate the interior from the outer environment and was implanted in a gap between proximal and distal stumps of transected sciatic nerve of an adult Wistar rat. Ten days later, the implanted silicone tube was prepared for electron microscopic observations. Schwann cells in the tube were elongated longitudinally and lined up parallel to the proximo-distal direction. No regenerating axons penetrated the Millipore membrane into the tube. The basement membrane showing almost normal structure was produced on the surface of the Schwann cells. While the silicone tube was placed side by side to the intact sciatic nerve, Schwann cells in the tube were scattered and no basement membrane was observed. These results suggest that some humoral factors might be released from the transected nerve stumps, which may be responsible for the regular arrangement and the basement membrane formation by Schwann cells without any contact with axons.     

Measurement of RF Transmission Mode in ITER Relevant EC H&;CD Transmission Line

The preliminary results of mode measurement in the ITER relevant 40 m long transmission test line composed from 63.5 mm diameter corrugated waveguides and miter bends are presented. The field patterns were measured by taking temperature profiles on a paper screen placed in front of the waveguide end using an infrared imaging camera. The complex electric field at the waveguide end was retrieved from the measured temperature profiles. As a result, the transmission power includes 87% of HE₁₁ mode and 6% of LP₁₁ odd (HE₂₁+TE₀₁) mode and small ratios of other modes. The mode content had small dependence on length of the transmission line. This result indicated that the higher order mode content generated at the input of the transmission line is conserved and propagated through the transmission line. This suggests that the initial RF coupling to the waveguide is critical since it affects the launcher efficiency.     

Evidence for Altered Phosphoinositide Signaling-Associated Molecules in the Postmortem Prefrontal Cortex of Patients with Schizophrenia

Phosphoinositides (PIs) play important roles in the structure and function of the brain. Associations between PIs and the pathophysiology of schizophrenia have been studied. However, the significance of the PI metabolic pathway in the pathology of schizophrenia is unknown. We examined the expression of PI signaling-associated proteins in the postmortem brain of schizophrenia patients. Protein expression levels of phosphatidylinositol 4-phosphate 5-kinase type-1 gamma (PIP5K1C), phosphatidylinositol 4-kinase alpha (PIK4CA, also known as PIK4A), phosphatase and tensin homolog deleted from chromosome 10 (PTEN), protein kinase B (Akt), and glycogen synthase kinase 3β (GSK3β) were measured using enzyme-linked immunosorbent assays and multiplex fluorescent bead-based immunoassays of the prefrontal cortex (PFC) of postmortem samples from 23 schizophrenia patients and 47 normal controls. We also examined the association between PIK4CA expression and its genetic variants in the same brain samples. PIK4CA expression was lower, whereas Akt expression was higher, in the PFC of schizophrenia patients than in that of controls; PIP5K1C, PTEN, and GSK3β expression was not different. No single-nucleotide polymorphism significantly affected protein expression. We identified molecules involved in the pathology of schizophrenia via this lipid metabolic pathway. These results suggest that PIK4CA is involved in the mechanism underlying the pathogenesis of schizophrenia and is a potential novel therapeutic target.     

Determination of alkylphenols,bisphenol A,benzophenone and phthalates in containers of baby food,and migration into food simulants

Infants, whose growth and development are highly dependent upon the endocrine system, are particularly vulnerable to endocrine disruptor exposure. In our study, we examined whether or not alkylphenols, bisphenol A, benzophenone, di(2-ethylhexyl)adipate and 10 phthalates are present in containers of baby food. Furthermore, the migration into food-simulating solvents was also examined. Sixteen types of containers of baby food, obtained on the Japanese market in 2001, were examined: 8 glass bottle types, 1 plastic type, 1 metallic package (laminated with plastic) and 6 multilayered laminated film packages. Alkylphenols, benzophenone, bisphenol A and di(2-ethylhexyl)adipate were not detected in any of the samples. On the other hand, dibutylphthalate (DBP) was detected in 7 samples (1.2-9.1 micrograms/sample), and di(2-ethylhexyl)phthalate (DEHP) was detected in 15 samples (1.3-18 micrograms/sample). Migration tests were carried out for 5 samples, and the levels of DBP and DEHP that migrated into n-heptane were 0.68-1.7 micrograms/sample and 0.33-3.5 micrograms/sample, respectively. From these results, a baby's intake levels of DBP and DEHP were estimated to be about 1/2,500 and 1/90-300 of the tolerable daily intake (TDI), respectively.     

A MAGE-1-encoded HLA-A24-binding synthetic peptide induces specific anti-tumor cytotoxic T lymphocytes

Although several MAGE-1 peptides have already been identified, the MAGE-1-encoded peptide presented by HLA-A24, which is the most common allele in Japanese population and is also frequently present in Caucasians, might have a wide applicability for immunotherapy using these peptides. To identify this potential peptide, we examined the induction of specific cytotoxic T lymphocytes (CTL) from the peripheral-blood mononuclear cells (PBMC) in HLA-A24 healthy donors by in vitro stimulation with MAGE-1-encoded synthetic peptides with a binding affinity for HLA-A24, by a simplified method. Of the 5 peptides tested, the highest HLA binder (NYKHCFPEI) was able to elicit CTL from unseparated PBMC by stimulation with freshly isolated, peptide-pulsed PMBC as antigen-presenting cells (APC) and by also using interleukin 7 and keyhole-limpet hemocyanin for a primary culture. The induced CTL could thus lyse HLA-A24 tumor cells expressing MAGE-1, as well as the peptide-pulsed target cells, in an HLA-class-I-restricted manner. By using the MAGE-1/HLA-A24 peptide, NYKHCFPEI, we found it possible to immunize many more patients, especially Japanese patients, by means of such peptide-based immunotherapeutic approaches to MAGE-1-positive malignant tumors.