Magnesium silicide has been investigated since for over 30 years because of its superior thermoelectric characteristics and lightweight. Its practical use, however, has not been realized yet, since the main component Mg is hard to be handled. Magnesium silicide bulk is almost produced by sintering with pressing such as spark plasma sintering or hot-pressing. Sintering with pressing is unsuitable for mass-production because of the small product size and the high production cost. In this work, a modified process of usual pressure-less sintering, which is useful for mass-production, was employed to produce sintered bodies of magnesium silicide. Pressing in an inert gas atmosphere successfully yielded pressure-less sintered bodies with a sufficiently small unevenness of the characteristics. The sintered bodies obtained were confirmed to have the superior thermoelectric properties, namely a Seebeck coefficient of -162 μV/K, a resistivity of 0.15 mΩm and 2.54 W/mK for n-type; +209 μV/K, 0.017 mΩm and 2.73 W/mK for p-type.

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Magnesium tin silicide (Mg₂Si_1−ySn_y) is a thermoelectric material with a low environmental load and a high power factor of approximately 400°C. High power factor sintering bodies by pressure-less sintering (PLS) have not been produced as Mg contained in the starting material is likely to be oxidized. A certain amount of tin is used as a sintering additive to improve the sintering density and power factor in liquid-phase sintering and the PLS process (LP-PLS). As a result, LP-PLS bodies with a power factor comparable to that of spark plasma sintering (SPS) bodies were successfully fabricated in this work. No significant changes in thermoelectric characteristics were observed even after heat treatment at 250°C for 32 h in air.

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In the studies on 21 HBsAg positive families in Iriomote Island, Nichinan and Fukuoka City, 99 HBsAg positive cases were tested for the presence of and eAb.
and eAb were detected in 35.4% and 20.0%, respectively. was detected more frequently in young age group and its highest positive rate was observed in age of under 9. The frequency of eAb was highest in age of 10-19.
Two years follow up study on 14 cases revealed no changes in 10 cases with or eAb and acquisition of or in 4 cases during the period of observation.
In 5 out of 6 families in which parents were negative for HBsAg and 2 or more children were positive, was detected at least in one of children and positive rate reached to 66.7%. In contrast to these families, 7 families with single HBsAg positive case had no positive case.
These results suggest that is closely associated with infectivity of HB virus and suggest the possibility of horizontal transmission in intrafamilial spread.

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The use of diesel engines has increased greatly in recent years. Diesel engines provide the power for most large trucks, trains, and construction and farm machinery. This has led to concern about the contribution of diesel engine exhaust gas to the air pollution. Although many of the pollutants emitted by diesel engines have been studied, the toxicological effects of complete exhaust gas have not yet been elucidated.
In the present investigation we tried to elucidate the chronic effect of diesel-engine exhaust gas on metabolic functions in rat lungs. Rats were exposed to diesel-engine exhaust gas for periods of from 1 week to 6 months. Fifty percent effective doses of acetylcholine in isolated rat tracheal strips, conversion or inactivation of vasoactive substances through isolated perfused rat lung lobes and change of plasma levels of serotonin and histamine were examined. Rats were classified into 3 groups, i.e. control group, filtered exhaust gas (F..) group and exhaust gas (.) group.
1. Fifty percent effective doses of acetylcholine in F.. and . rat (3-6 months) tracheal strips showed a significant decrease compared with that of control rats.
2. Inactivation of serotonin through isolated perfused lung lobes in . and F.. groups exposed for 6 months showed a decrease compared with that in the control group.
3. Inactivation of prostaglandin E₂ and F_2α through isolated perfused lung lobes in . and F.. groups (exposed for 1 week to 6 months) showed a decrease compared with that in the control group.
4. Conversion of angiotensin I to angiotensin II through isolated perfused lung lobes in . and F.. groups (exposed for 6 months) showed an increase comparing with that in the control group.
5. Plasma level of serotonin did not show any significant differences among these three groups, while the plasma level of histamine in . and F.. group (exposed for 6 months) showed a significant increase compared with that in the control group.
The above results suggest that long term exposure of diesel-engine exhaust gas may affect pulmonary metabolic functions.

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For the purpose of studying the significance of glucose-6-phosphate dehydrogenase in erythrocytes (--6-PD) in childhood, the auther has determined --6-PD obtained from healthy and sick children.
Results were as follows ;
1) --6-PD activity in healthy children indicated high value in their neonatal period decreasing gradually till they reached to six months after birth and showed constant value thereafter.
2) Much higher activity of --6-PD were observed in premature neonates as compared with those of matured.
3) --6-PD activity in neonatal hyperbilirubinemia due to ABO incompatibility between mother and baby showed somewhat low in premature compared with matured.
4) --6-PD activity of hemolytic anemia showed remarkable increase, while lower in aplastic anemia.
5) Relations between --6-PD and E-GOT varied with various hematologic disorders and no significant correlation was observed.
6) Among the patients with anoxic status, both --6-PD and E-GOT in congenital heart disease showed high activity, while elevated E-GOT but no elevation of --6-PD wass shown in patients with asthmatic crisis.
7) --6-PD activity in acute glomerulonephritis and nephrotic children remainedt within normal range regardless the presence of anemia. --6-PD of diabetic child showed low value immediately after starting treatment.

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Electro-adhesive gel () is a functional material which changes its surface adhesive property according to applied electrical field. This unique property is called "Electro-adhesive effect". In this paper, is applied to a semi-active seismic damper to suppress earthquake-excited vibrations of buildings. The damper has a simple structure and provides superior performance compared with a conventional damper such as an oil damper or a MR damper. Furthermore the damper can serve both as friction damper and viscous damper by controlling applied electric field. In this paper, a small damper is produced experimentally, and the effectiveness of the damper installed in base isolated buildings is verified from the simulation.

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This experiment investigated the learning of Kana and Kanji by four-year-old children under the following conditions: C1: Kana+syllable, ., _??_+“ku”; C2: Kana+syllable+picture representing a word beginning with the preceding syllable, ., _??_+“ku”+picture of kuma (bear); C3: Kana+syllable+word which begins with the preceding syllable, ., _??_+“ku”+“kuma”; C4: Kana+syllable+word+picture; C5: Kanji+word, ., _??_+“inu” (dog); and C6: Kanji+word+picture, ., _??_+“inu”+picture of inu. The Kanji conditions (C5 and C6) were the easiest. Association with meaningful words or pictures did not significantly improve Kana learning.

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Al₂O₃//ZrO₂ ternary MGCs (Melt Growth Composites) with a new microstructure have been fabricated by unidirectional solidification. The superior high-temperature strength of Al₂O₃//ZrO₂ ternary MGCs over Al₂O₃/ binary MGCs was obtained by the following means: a new combination of single-crystal Al₂O₃ with a hexagonal structure, single-crystal with a garnet structure and Zr_0.8Er_0.2O_1.9 phases with a cubic structure; a microstructure consisting of three-dimensionally continuous and complexly entangled single-crystal Al₂O₃, single-crystal YAG and Zr_0.8Er_0.2O_1.9 phases; characteristic dimension of the microstructure around 2∼4 μm (this dimension is defined as the typical length of the short axis of each domain seen in the cross-section perpendicular to the solidification direction) for phases, around 2∼4 μm for Al₂O₃ phases reinforced with around 0.4∼0.8 μm Zr_0.8Er_0.2O_1.9 phases. These features are finer than that for the Al₂O₃/ binary MGC. No amorphous phases are formed at interfaces between phases in the ternary MGC.

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The essay sketches some conspicuous aspects of Ovid's usage of color-terms (voc. suggestive of colors, incl. n., adj. and verbal forms) in his epic narratives, in an attempt to restate the lines of demarcation between the poetic colors and those of (in his case)often-compared visual arts. Materials of the discussion are mainly drawn from the Metamorphoses, and treated in the following order, I. Epitheton ornans and its various modifications : i)suggestive of concrete texture of color-bodies(. I 332-3, II 852-3) ; ii)merging of color-similes in actions (. IV 354-5, X 594-5) ; iii)metrical device to enhance coloration(. VIII 354-5, X 90-105). II. Symbolic uses(or suppression)of color-terms: Aurora in III 145-252; colorless effect of quod rogis superest in IV 164-6. III. Significant color-contrasts in Ovidian narrative: i) green and earth-colors (. I 112, 632-41, II 864-5, limum infronde relictum I 347) ; ii)blood on green grass(. Ill 86-7, IV 504-5, X 210), murder of Orpheus(XI 18-9, 27-8) and death of Ajax(XIII 394-5), guilty civilization(XV 96-8) ; iii)red and white: cliche split into multiplicity of meaning(. Ill 418-24, 481-4, 491, 509-10), beauty-spot turned into the utmost misery(. XIII 492) ; pristine freshness of Dawn, distilled from cliche by magic art, X 291-4.

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