Electron transport in InGaO3(ZnO)m (m=integer) studied using single-crystalline thin films and transparent MISFETs

We have investigated the characteristics of transparent metal-insulator-semiconductor field-effect transistors (MISFETs) fabricated using InGaO₃(ZnO)_m (m=integer) single-crystalline thin films as n-channel layers and amorphous alumina as gate insulator films. The MISFETs exhibit good characteristics such as insensitivity to visible light illumination, off-current as low as ∼1 nA with a positive threshold voltage of ∼3 V and on/off current ratio of 10⁵. The field-effect mobility increased from ∼1 to ∼10 cm² (V s)⁻¹ as the m-value increased. Room temperature Hall mobility also increased. However, unexpectedly these values were lower than the field-effect mobility. It is explained by existence of shallow localized state in the homologous compounds.     

An expert system for XPLE cable deterioration diagnosis and life forecasting

The recent increase in the demand for power in urban areas has caused changes in the way power is supplied. Underground distribution systems have been introduced for convenience in urban areas and to prevent injuries in case of a crisis. As a result, many new types of power cables are being used. One type, XPLE cables (also called CV cables) have been rapidly taking the place of conventional cables such as OF or SL cables since the 1960s because of their relatively easy installation and maintainability. However, distribution cables used under severe environmental conditions deteriorate rapidly (due mainly to water treeing), and some cables experience insulation breakdown. Therefore, many diagnostic methods have been developed, though they have not been very effective. By combining methods, a high reliability can be achieved in comparison to the use of a single method. However, processing the data is difficult for on-site personnel, so many experts are required. But there is a lack of qualified experts, hence we have turned to the development of expert systems.     

Radiation tolerance for the SMASH-series front-end chips for a silicon micro-strip detector

The radiation tolerance for prototype front-end chips designed for a silicon micro-strip detector was examined with a ⁶⁰Co irradiation source to establish an allowable range of the radiation dose. The irradiated front-end chips were SMA²SH-64A, a 64-channel preamplifier array; SMA²SH-1, a single-channel preamplifier circuit with a comparator; and Control-C, a digital-control chip for the preamplifiers.     

X gene and precore region mutations in the hepatitis B virus genome in persons positive for antibody to hepatitis B e antigen: comparison between asymptomatic "healthy" carriers and patients with severe chronic active hepatitis

Hepatitis B virus (HBV) carriers with antibody to hepatitis e antigen comprise asymptomatic carriers (ASCs), who have low replication levels of HBV, and patients with chronic active hepatitis (CAH), who have high levels of viral replication. To investigate whether defects in the X protein might be responsible for this difference in the level of viral replication, nucleotide sequences of X and precore gene regions in serum HBV were analyzed in 19 ASCs and 9 CAH patients. All patients had a point mutation creating a stop codon in the precore region. Seventeen ASCs (87.3%) had identical mutations consisting of 4 noncontiguous 1-bp deletions or an 8-bp deletion, both of which truncate the normal X protein, whereas no CAH patient had an X gene mutation (P < .001). Thus, deletion of the X protein might be responsible for the low levels of viral replication in ASCs.     

Clinical study of total intravenous anesthesia with droperidol, fentanyl and ketamine--effects of nicardipine, diltiazem and nifedipine on intraoperative hypertension

The purpose of the study was to explore the relationship between the exposure of adolescents in the seventh and eighth grades to cigarette advertising and their being smokers. A survey questionnaire given to 602 adolescents assessed their exposure to cigarette advertising and provided measures of their smoking behavior, demographic characteristics, and some psychosocial variables. The results indicated that exposure to cigarette advertising and having friends who smoked were predictive of current smoking status. Adolescents with high exposure to cigarette advertising were significantly more likely to be smokers, according to several measures of smoking behavior, than were those with low exposure to cigarette advertising. The findings extend previous research identifying factors that may play a role in the initiation and maintenance of smoking among adolescents.     

Successive overrelaxation method with projection for finite element solutions of nonlinear radiation cooling problems

In this paper, we consider the successive overrelaxation method with projection for obtaining the finite element solutions under the nonlinear radiation boundary conditions. In particular we establish the convergence of the successive overrelaxation method with projection. Some numerical results are also given to illustrate the usefulness.     

Dissolution of Ti wires in sulphuric acid and hydrochloric acid solutions

Ti wire electrodes were immersed in acidic solutions containing H₂SO₄ and HCl of various concentrations at 353 K to evaluate corrosion rate by measurement of electric resistance change (resistometry). Addition of hydrochloric acid to sulphuric acid solution promoted depassivation of Ti. After depassivation, the immersion potential dropped to the hydrogen evolution potential and a hydride layer was formed on the surface. The hydride layer dissolved continuously in the acidic solution. SEM observation showed that Ti wires dissolved almost uniformly in the early stage and that the dissolution then trace became irregular due to nonuniform growth of the hydride layer. Dissolution rate of a Ti wire was estimated almost accurately by resistometry.     

Occurrence of heterogeneity of N-linked oligosaccharides attached to sycamore (Acer pseudoplatanus L.) laccase after excretion

The N-linked oligosaccharide moieties of sycamore (Acer pseudoplatanus L.) laccase are known to be highly heterogeneous. We confirmed that this oligosaccharide heterogeneity was caused not only during the oligosaccharide biosynthesis in Golgi apparatus, but also after the excretion of laccase protein into a culture medium. The culture medium for the sycamore cells (Acer pseudoplatanus L.) contained beta-galactosidase, alpha-L-fucosidase, beta-N-acetylglucosaminidase, alpha-mannosidase and beta-xylosidase activities. We showed that the largest sugar chain in laccase, oligosaccharide F, [formula: see text] was degraded to [formula: see text] by a crude exoglycosidase mixture in the culture medium.     

Antigenic and genetic diversities of Babesia ovata in persistently infected cattle

Exploring the antigenic and genetic diversities of Babesia ovata, we obtained several field isolates from grazing cattle in the Okushiri island, Japan. Parasite isolation was greatly facilitated by using bovine red blood cell-substituted SCID mice (Bo-RBC-SCID mice), into which the blood samples of the cattle were inoculated. Isolates from different individuals within a herd of cattle were compared in immunoblot analysis with an anti-B. ovata serum and also in Southern blot analysis with a probe for the small subunit ribosomal RNA gene. In both analyses, the isolates exhibited banding patterns that were significantly different from each other. We were also able to obtain a series of parasite isolates from a single cow in different seasons of a nine months period, including winter when active vector ticks were not in the field environment. Different seasonal isolates showed different banding patterns in both immunoblot and Southern blot analyses. By contrast, these analyses detected little difference among the parasites that had been passed various times in Bo-RBC-SCID mice, where no specific immune responses should be generated. These results indicate that individual animals within a herd of cattle were infected with antigenically and genetically diversified populations of B. ovata, and that the parasites could persistently infect a single animal with dynamic change in their predominant subpopulations.