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ポリビニルアルコール（PVA）水溶液で湿ったガラス微粒子層の伝導－対流乾燥では，乾き材料内部で伝導と乾燥の両面付近にPVAが偏在することが知られている．伝導面側熱風温度を一定に保ち，乾燥面側熱風温度を変化させて伝導－対流乾燥実験を行った結果，乾燥面側熱風温度が低いほど伝導面側でPVAが大きく偏在した．このとき乾燥速度は小さくなった．また初期含溶液率が小さな試料では偏在が生じなかった．

The nucleotide sequences of the envelope protein of the Kamiyama 1 strain of Japanese encephalitis (JE) virus and a passaged mutant (Kamiyama 2 strain) were determined. Two amino acid differences, Ser-Phe at residue 364 and Asn-Ile at residue 367, distinguished Kamiyama 2 from Kamiyama 1. Six neutralization-resistant variants were selected from these two strains using a JE species-specific monoclonal antibody with neutralization and hemagglutination-inhibition reactivities. All variants had a single amino acid substitution at residue 52 and significantly reduced reactivity with other JE species-specific monoclonal antibodies. The variants derived from Kamiyama 2 strain showed reduced virulence in 3-week-old mice after peripheral inoculation but were as virulent as the parent virus when inoculated intracranially. These variants also showed altered early virus-cell interaction but not replication and reproduction in Vero cells. These findings indicate that the mutations at residues 52, 364, and 367 affect early virus-cell interaction in Vero cells and virulence in mice.

Ultra thin silicon nitride films have been indispensable in high density memory devices as a dielectric. We investigated the effect of the silicon surface state on initial silicon nitride growth process, we have used X-ray Photoelectron spectrometry (XPS), Secondary ion mass spectrometry(SIMS), and Capacitance-Voltage(C-V) characteristics. The results of our study show that the fluorine on silicon surface influences initial silicon nitride growth. The presence of fluorine delays low pressure chemical vapor deposition(LPCVD) silicon nitride growth as well as restraining native oxide growth at the silicon nitride/silicon substrate interface. We propose that it is a key process of thin dielectric films deposition to control fluorine on silicon surface.

An investigation of flow and heat transfer characteristics in a two-phase double-tube thermosyphon was performed experimentally using water, ethanol, and Freon 113 (R113) as the working fluids. A theoretical study was also made on the circulation mass velocity. As the heat flux increased, the experimentally measured circulation mass velocity first increased and then decreased. After that, for ethanol and Freon 113, the mass velocity increased again at a certain heat flux, where the heat transfer coefficient also increased stepwise, and then decreased. It seems that this peculiar behavior was caused by a change in flow pattern. For water, the calculated circulation mass velocity agreed well with the experimental results. For ethanol and Freon 113, however, the agreement was not good enough because the change in the flow pattern was not taken into consideration in the theoretical calculation. The calculated mass velocity, however, did indicate the average line passing through the experimental data.

Experiments have been made to clarify the effects of the thickness, aspect ratio and height of honeycomb structures on the performance of honeycomb solar collectors, and a new model, in which the honeycomb heat capacity and the absorption of the solar irradiation by the honeycomb wall are taken into account, has been proposed to predict the performance. Calculated values by this model agree better with the experimental results than those by a previous model, and the suitable honeycomb thickness, aspect ratio and height are determined by using this model. Furthermore, the performance of the honeycomb collector is compared with those of other types of collectors and the effectiveness of the honeycomb collector is indicated.

Effects of the configuration of a finned tube on the heat transfer characteristics of latent heat storage have been studied experimentally and theoretically. As a result, it has been shown that the performance of the latent heat storage unit is almost the same for finned tubes having the same surface area even if the fin configuration is different. Calculated results of heat fluxes for two types of finned tube have been in good agreement with the experimental values, and the validity of the calculations has been indicated.

SummaryThe rapid increase in the elderly population is leading to a corresponding increase in the number of people requiring medical care. To date no comparative study between community-acquired pneumonia (CAP) and nursing home-acquired pneumonia (NHAP) has been reported in the very elderly non-intubated patients. The present study was undertaken to compare the clinical characteristics and microbial etiology between CAP and NHAP in elderly patients ≥85-years old. There were 54 patients with NHAP and 47 with CAP. Performance status was significantly worse in the NHAP than in the CAP group. Among all patients, the most frequent pathogens were Chlamydophilia pneumoniae followed by Streptococcus pneumoniae, Mycoplasma pneumoniae influenza virus and Staphylococcus aureus. The frequency of S. peumoniae was significantly higher in NHAP patients than in CAP patients after adjusting for age and sex. Physical activity, nutrition status and dehydration were significant prognostic factors of pneumonia among all patients. In-hospital mortality was significantly higher in NHAP than in CAP after adjusting for age and sex. This study demonstrated that the etiology and clinical outcome differ between CAP and NHAP patients in the very elderly non-intubated population.

Interfaces between two kind of substrate, a bulk silicon wafer and a laser-recrystallized Silicon-On-Insulator (SOI), and its thermally grown oxide have been studied. High resolution transmission electron microscopy (HRTEM) of cross sectional specimen shows that the roughness at the interface is atomically flat and nearly uniform for the bulk single crystal silicon and silicon oxide, while being nonuniform and rough as much as 20 nm height for the recrystallized silicon and silicon oxide interface. Consideration of interface between recrystallized silicon and silicon oxide, and the oxide surface above, the observed roughness at the interface is due to original grain boundaries of polycrystalline silicon which was used as the material for the laser recrystallized silicon formation. It is also discussed HRTEM of the interface between polycrystalline silicon and silicon oxide.

顕著な乾燥収縮を起こす粒子分散系塗布層のモデル系としてゴムラテックス液で十分に湿った脱脂綿薄層を高分子フィルム基材上に乗せ，上下両面から熱風を供給することで，薄層の対流－伝導乾燥を，高温高速（上）－低温低速（下）または低温低速（上）－高温高速（下）熱風を用いて行い，液の初期水分濃度を変えて乾燥速度を測定した．乾燥速度は初期水分濃度が低いほど小さくなった．乾燥所要時間は高初期水分濃度域においては高温高速－低温低速条件下で短くなったが，低初期水分濃度域では逆に低温低速－高温高速条件下で短くなった．このとき乾き層の収縮の程度は液の初期水分濃度に依存しなかった．これらの結果は，報告済みのポリビニルアルコール（PVA）水溶液で湿った場合と同様であった．しかしラテックスでは，PVAに比べて全般に乾燥速度が大きく，乾燥所要時間の逆転が生じる初期水分濃度は小さくなった．また乾き層の力学的強度は弱かった．

A study of Bi-Sr-Ca-Cu-O thin films soaked in water demonstrated that film superconductivity was degraded by exposure to water. ICP analysis showed that Sr and Ca, but no Bi and Cu, largely dissolved. EPMA analysis indicated that dissolution took place mostly in nonsuperconducting grains. By contrast, XRD patterns showed no significant change after soaking. That is, superconducting grains were indeed stable, but nonsuperconducting grains were notably degraded in polycrystalline films, with a consequent lowering of overall superconductivity.