Doped Perovskite Oxide, PrMnO3, as a New Cathode for Solid-Oxide Fuel Cells that Decreases the Operating Temperature

Cathodic overpotentials of Ln_0.6Sr_0.4MnO₃ (Ln is La, Pr, Nd, Sm, Gd, Yb, and Y) were studied for a new cathode for solid-oxide fuel cells (SOFCs) with low overpotentials in a relatively-low-temperature region. Cathodic overpotentials strongly depended on the rare-earth cations in the A sites of the perovskite oxide. In particular, overpotentials of a Sr-doped PrMnO₃ cathode maintained low values despite decreased operating temperature. Consequently, almost the same power density of a SOFC with Ln_0.6Sr_0.4MnO₃ cathode was obtained at about 100 K lower operating temperature by using Sr-doped PrMnO₃ as the cathode.     

Ionic conductivity of electrolytes formed from PEO-LiCF3SO3 complex low molecular weight poly(ethylene glycol)

Films of poly(ethylene oxide)-LiCF₃SO₃-based complexes containing different amounts of poly(ethylone glycol) (PEG) with molecular weights ranging from 400 to 2000 were prepared by solution casting. The ionic conductivity is presented as a function of temperature, molecular weight and the PEG content used. The conductivity increases with decreasing molecular weight of PEG and with increasing PEG content. The incorporation of PEG with a molecular weight of 600 or less gives rise to a maximum conductivity value of 3 × 10^–3 Sm^–1 at 25° C. The conductivity enhancement at room temperature can be attributed to the increase in the amorphous regions responsible for the ionic conduction.     

Digital input filters for measurement,control and protection of electric power systems

Power system control and protection equipment has required higher sensitivity and operational reliability than conventional one. Studies of digital signal processing suitable for electric power systems fulfill this objective using fast sampling and digital filtering by a 32-bit floating point DSP (Digital Signal Processor). The sampling rate of 3 kHz is carefully selected in order to separate the power spectrums of the A-D conversion output errors from the signal bandwidth. The new 12-bit A-D conversion unit equipped with a recursive-type digital filter achieved the equivalent high resolution of 14-bit conversion. This paper describes the design concept and the characteristics showing applications to current differential relays, distance relays and power system controllers.     

Measurement of the plastically deformed domain caused by microdrilling in CdS single crystal

Vertical microdrilling tests with a rotary speed of 3760 rpm and a feedrate of 5 μm/s on the (0001) surface in CdS single crystals using twist drills with diameters of 50, 60, 70, 80, and 90 μm are performed. Plastically deformed domains at neighborhoods of those holes and of drill tips are investigated by chemical etching and mechanical polishing. The results obtained are as follows: As the diameter of the drill increases, the difference between the typical length of a plastically deformed domain and the diameter of a surface hole decreases in the case of constant working depth 120 μm and is nearly constant in the case of the constant ratio working depth/drill diameter = 2. The plastically deformed domain in the axial direction of the drill is smaller than that in the radial direction.     

Characterization of gamma rays existing in the NMIJ standard neutron field

Our laboratory provides national standards on fast neutron fluence. Neutron fields are always accompanied by gamma rays produced in neutron sources and surroundings. We have characterised these gamma rays in the 5.0 MeV standard neutron field. Gamma ray measurement was performed using an NE213 liquid scintillator. Pulse shape discrimination was incorporated to separate the events induced by gamma rays from those by neutrons. The measured gamma ray spectra were unfolded with the HEPRO program package to obtain the spectral fluences using the response matrix prepared with the EGS4 code. Corrections were made for the gamma rays produced by neutrons in the detector assembly using the MCNP4C code. The effective dose equivalents were estimated to be of the order of 25 microSv at the neutron fluence of 10(7) neutrons cm(-2).     

Antiferromagnetic Ordering in the One-Dimensional Edge-Sharing CuO2 Chain System Ca2+x Y2−x Cu5O10

We have investigated the spin state of the one-dimensional edge-sharing chain system Ca_2+x Y_2–x Cu₅O₁₀ with 0x1.667 by means of the magnetic susceptibility and specific heat measurements, using the large-size single-crystals. It has been found that the magnetic ground state is an antiferromagnetically ordered state for 0x1.0, while a spin-gap state seems to be formed for x1.5. Accordingly, it appears that the quantum critical point is located between x=1.0 and 1.5 in Ca_2+x Y_2–x Cu₅O₁₀.     

Expression of CD44 containing variant exon 9 (CD44v9) in gastric adenomas and adenocarcinomas: relation to the proliferation and progression

The expression of CD44 splice variant containing exon 14 (variant exon 9: CD44v9) was examined immunohistochemically in non-neoplastic mucosa, adenoma and adenocarcinoma of the stomach and analyzed the relation with the expression of Ki-67 antigen and p53 protein. In non-neoplastic gastric mucosa, basolateral membrane of the epithelial cells in the pyloric glands showed the expression of CD44v9. The epithelial cells in the intestinal metaplastic mucosa of the stomach sometimes expressed CD44v9. In the neoplastic lesions, the expression of CD44v9 was detected in 20% (34/170) of the adenomas and 28% (132/478) of the adenocarcinomas, respectively. The incidence of CD44v9 expression did not differ among histological type of gastric carcinoma. Twelve per cent of the adenocarcinomas showed strong expression of CD44v9, whereas non of the adenomas did. The incidence of CD44v9 expression was significantly higher in carcinomas invading into muscularis propria or the cases of stages 3 and 4 in comparison with that in carcinomas limited to submucosa or the stages 1 and 2 cases (p<0.05). The incidence of positive cases was higher in carcinomas with lymph node metastasis than those without metastasis (p<0.05). The expression of CD44v9 was significantly correlated with the expression of Ki-67 (p<0.05). It was also correlated with the expression of p53 protein in the tumor cells (p<0.01). These findings overall suggest that the expression of CD44v9 may be associated with the development as well as progression of the gastric carcinomas.     

Effects of olprinone on IL-6 and IL-10 production during and after cardiac surgery

Phosphodiesterase inhibitor (PDEI) has been accepted as an inodilator with positive inotoropic and vasodilating actions. Recently many new PDEIS have been available for the treatment of heart failure. We investigated the effect of a new PDEI-III agent, olprinone, on IL-6 and IL-10 production during and after coronary bypass graft surgery (CABG). Twelve patients scheduled for CABG were assigned to 2 groups. In 6 patients (Group-O), olprinone was administered continuously for 30 minutes at a rate of 0.3 micrograms.kg-1.min-1 (gamma) after the anesthesia induction. Then, the infusion rate of olprinone was decreased to 0.2 gamma and it was kept until the 3rd post-operative day. In another 6 patients (Group-C), phentolamine was used for vasodilator instead of olprinone. The plasma levels of IL-6 in Group-O did not show any significant change during perioperative period, whereas those in Group-C reached the peak at the end of extracorporeal circulation and did not recover to control level until the 3rd post-operative day. The plasma levels of IL-10 in Group-O increased to the maximum level at the end of extra-corporeal circulation and were significantly higher than those in Group-C. It is suggested that olprinone has not only inodilating action but also anti-inflammatory action at therapeutic concentrations used for heart failure.     

Hepatoid carcinoma of the lung with production of alpha-fetoprotein and abnormal prothrombin: an autopsy case report

Alpha-fetoprotein (AFP) is a useful tumor marker for the diagnosis of hepatic and testicular tumors. Several cases of AFP-producing lung cancer have been reported. We present here a patient with AFP-producing primary lung carcinoma, which showed high values of serum AFP (100,000 ng/mL). The concanavalin A nonbinding fraction rate of AFP was 15%. Gross and microscopic features of the lung carcinoma bore a striking resemblance to those of hepatocellular carcinoma. According to the histologic classification of lung tumor, this case was large cell carcinoma with prominent hepatoid differentiation. Immunohistochemically, we detected AFP in the cytoplasm of the neoplastic cells. We also detected another useful tumor marker for the diagnosis of hepatocellular carcinoma, i.e., des-gamma-carboxy prothrombin (protein induced by vitamin K absence or the absence of antagonist-II [PIVKA-II]), in serum using an enzyme immunoassay and in tumor cells by immunohistochemical analysis.     

Reduced expression of cyclin-dependent kinase inhibitor p27Kip1 is associated with advanced stage and invasiveness of gastric carcinomas

Reduced expression of a cyclin-dependent kinase inhibitor p27Kip1 has recently been shown to predict poor survival of patients with breast and colorectal cancers. We studied the expression of p27Kip1 in gastric carcinomas by northern blotting, western blotting and immunohistochemistry to determine whether lack of p27 has implications for aggressiveness of gastric cancer. Reduced expression of p27 was detected in 40% of the gastric carcinomas at the mRNA level, while it was detected in 57% at the protein level. No gross alterations of the p27 gene were observed in any of the cases examined by Southern blot analysis. Immunohistochemical studies revealed that the expression of p27 was well preserved in most of the gastric adenomas, whereas it was so in only 26% of the gastric carcinomas. Fifty-six percent of the carcinomas showed almost no p27-positive cells. Decrease of p27-positive cells significantly correlated with advanced stage, depth of tumor invasion and lymph node metastasis. The expression of p27 showed an inverse correlation with the expression of cyclin E. These findings suggest that reduction of p27Kip1 protein may reflect the progression of gastric carcinomas and may be an indicator of high-grade malignancy.