【背景】遺伝子多型による毒性の差を検討する簡易な毒性試験の手法は確定していない。しかしながら対象人口が大きく、毒性の差が予想される遺伝子および毒物も少なくない。エタノール中間代謝産物のアセトアルデヒドは主にアルデヒド脱水素酵素(ALDH)2が代謝する。日本人のおよそ半数はALDH２が不活性型であり、飲酒後フラッシング反応を示す。アセトアルデヒドは室内環境汚染物質の１つであるが、アセトアルデヒド全身曝露による毒性がALDH２不活性で異なるかは不明である。
【目的】モデル動物であるAldh2-/-マウスを用いアセトアルデヒド急性曝露時においてALDH2活性の有無により毒性症状に差はないか急性全身曝露実験を行い評価した。
【方法】Aldh2-/-および野生型マウス（Aldh2+/+）（各n=5）をアセトアルデヒド5000ppmの密閉容器に投入し 4時間全身曝露した。マウスの経過を観察とともに、曝露終了時の血中アセトアルデヒド濃度をHead space GC-MS法を用い測定した。
【結果・考察】Aldh2+/+に比べAldh2-/-は呼吸数減少、活動低下など麻酔症状が強く現れた。血中アセトアルデヒド濃度はAldh2-/- が200μmole/g、Aldh2+/+が85μmole/gとAldh2+/+に比べAldh2-/-の血中アセトアルデヒド濃度が有意に高値であった。死亡数および毒性症状をOECD TGの分類にあてはめると、アセトアルデヒド急性曝露は１クラスの差をしめす。ヒトにおいてもALDH2不活性型のヒトはと活性型のヒトと比べ、アセトアルデヒド全身曝露毒性が強く発現する可能性がある。

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With the global changes of the automobile market, the design and development of an automobile in consideration of various corrosive environments are required. It is necessary to immediately grasp the corrosive environment of the automobile market quantitatively. Therefore, even a system that could measure the corrosive environment of transit-time has been developed. Various areas of a corrosive environment were measured continuously and quantitatively by using this system, and every the side of the automobile could be evaluated. In this study, the result of the measurement of an ACM sensor (Atmospheric Corrosion Monitor Sensor) that estimated the corrosive environment in particular to automobiles is reported.

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Dynamic strain aging improves the non-propagation limit of a fatigue crack in ferritic iron alloys containing supersaturated carbon. However, upon increasing the test temperature, the non-propagation limit of the fatigue crack decreases owing to carbide precipitation. In this study, we present a guideline to improve high-temperature fatigue resistance in ferritic steels containing supersaturated carbon via Si addition that suppresses carbide formation. Compared with a Fe-0.017C binary steel, at 293 and

K, the Si addition increased the fatigue limit at both temperatures as compared with that of the Fe–C binary steel. The higher fatigue limit than that of the binary alloy at 293 K originated from the solid solution strengthening of Si, whereas the improved fatigue limit in Fe-0.016C-1.0Si at K was attributed not only to the solution hardening, but also to the suppression of carbide formation at K. These results indicated that the robustness against temperature can be improved by the addition of Si. However, at K, as time passed, carbides precipitated and the Vickers hardness decreased finally even in the Fe-0.016C-1.0Si steel. Also, fatigue crack did not stop propagating at 293 and K. It is necessary to investigate this by observing the dislocation structure around the fatigue crack tip and fracture surface.

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A mobile antenna of the MHz band (wavelength 70 cm) in amateur radio generally has an element length of about 0.7 to 1.5m. There is no data of a moving antenna with an element length of about 10m. We devised and fabricated a 10 m long-wire inverted-L antenna and made a simple evaluation. In this paper, we describe the outline and effectiveness of this antenna.

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　In the Japanese population, D19S

silent allele is rarely detected in cases of testing with commercial STR kits. The silent allele causes inconsistency of STR typing results between kits and false negative parentage despite the true biological parentage. The cause of this problematical mismatch is reported that the mutation is a base change (G>A) 32 nucleotides downstream from the 3′ end of the AAGG repeats (G32A), so reverse primer in STR kits fail to anneal to the binding site, consequently no STR peak or extremely low peak is detected. In this study, volunteers originated from 4 silent-allelic pedigrees are examined whether the silent allele was judged by AmpFlSTR Identifiler Plus PCR amplification kit, PowerPlex Fusion system, and GlobalFiler PCR amplification kit, furthermore they carry G32A mutation or not by direct sequencing, SNaPshot genotyping, and TaqMan genotyping. In conclusion, it has been identified that all silent-allelic peaks are caused by G32A mutation and followed by Mendelian genetics. Actually, some factors influence the formation of silent allele, such as primer binding fidelity, improvement of other PCR reagents, and PCR cycle conditions. When the suspected silent-allelic peak appears, additional tests with multiple STR kits which containing alternative primer will be recommended.

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The growth of compounds during energization heating at the interconnection between a Sn-based solder and a multilayer Pd/Ni/Cu conductor may be inhibited by alloying of Pd with Cr. To examine such influence of Cr on the compound growth, the kinetics of solid-state reactive diffusion in the (Pd–Cr)/Sn system was experimentally determined in the present study. Experiments were conducted using Sn/(Pd–Cr)/Sn diffusion couples with Cr mol fractions of y = 0.110, 0.215 and 0.323 which were prepared by a diffusion bonding technique. The diffusion couples were isothermally annealed in the temperature range of T = –473 K for various times up to t = 360 h. During annealing, a compound layer consisting of different matrices and lamellar phases is formed at the original (Pd–Cr)/Sn interface in the diffusion couple. From the Pd–Cr side to the Sn side in the compound layer, the matrices are PdSn₂, PdSn₃ and PdSn₄, and the lamellar phases are (Cr_0.9Pd_0.1)₃Sn, (Cr_0.95Pd_0.05)₂Sn, (Cr_0.9Pd_0.1)Sn and CrSn₂. The total thickness of the compound layer is proportional to a power function of the annealing time. The exponent n of the power function is rather close to 0.5 independent of y at T = 453–473 K. At T = K, however, n ≅ 0.5 for y = 0–0.110, but n = 0.7–0.8 for y = 0.215–0.323. Thus, the overall compound growth is controlled by volume diffusion for y = 0–0.323 at T = 453–473 K and for y = 0–0.110 at T = K. On the other hand, for y = 0.215–0.323 at T = K, the interface reaction at the moving interface contributes to the rate-controlling process. The overall growth rate of the compound layer is insensitive to y at y < y_c but monotonically decreases with increasing value of y at y > y_c, where y_c = 0.1 and 0.2 at T = –453 K and 473 K, respectively. Consequently, the compound growth is actually decelerated by the addition of Cr with y > 0.2 into Pd in the multilayer Pd/Ni/Cu conductor.

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Galvanic corrosion between carbon steel and soldering fluxes was studied in a concentrated LiBr solution at 383 and K, using extreme-value statistical analysis of pit depth in soldered parts, measurement of the amount of dissolved Fe²⁺ and dissolved flux compornents, and corrosion potential and galvanic current measurement. The soldering fluxes used were copper, copper alloys (Cu-Si-Mn, BAg-8, Ag 30-Cu, 70/30 Cupronickle) and nickel.
Nickel flux soldered with carbon steel caused considerable galvanic corrosion of carbon steel at 383K, while carbon steel soldered with copper and copper alloy fluxes showed galvanic corrosion of the fluxes at 383 and K. The galvanic corrosion rate of fluxes decreased in the order of copper>Cu-Si-Mn>Ag 30-Cu>BAg-8> 70/30 cupronickel at K, and Cu-Si-Mn>copper>Ag 30-Cu>BAg-8>70/30 cupronickel at 388K. 70/30 cupronickel flux was considered the most suitable soldering flux in a concentrated LiBr solution at high temperature.

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前回の論文で著者は縫合下帯に生ずる疣の発育程度によってウミニナをA, B, Cの三型に分類した。全国的にみると, 同一環境下にある同一産地から採集したウミニナとホソウミニナの型の出現頻度は同一傾向を示している。この点は地理的分右上においても同じである。それで疣の発育は環境に支配されるものと推定した。しかしホソウミニナの方が環境の変化に敏感である。疣の発育を促す原因は海水の温度よりも寧ろやや大きい塩分濃度に関係があるものと推定される。

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Fajin 法進 (?-444) [a monk in the Northern Liang 北涼 (397-439)] took his life for the sake of starvelings in Turfan. This study is an investigation of the relationship between Fajin's action known as atmabhavaparityaga 捨身 and the Buddhism of the Northern Liang. By the way, this Buddhism developed through King Meng Xun's 蒙遜 (368-/r. 401-) devotion to Buddhism. In his reign, Fajin was given a warm reception by the king.
When the Northern Wei 北魏 (386-584) overpowered the Northern Liang in 439, the Northern Liang royal family led a retreat of some families to the west. Fajin was included, too. In 442 Wu Hui 無緯 (?-444/r. 443-444) occupied Turfan and established in the following year the Qoco 高昌 kingdom ruled by the Juqu 沮渠 family (442-460).

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The effect of 0.5 mass%Ca addition on the precipitation behavior of a Mg–6.0 mass%Zn–3.0 mass%Al (ZA63) alloy was investigated. The as-cast ZA63 and Ca-added alloys were homogenized and solid solution treated at 673 K for 12 and 1 h, respectively, followed by water-quenching. Then, both alloys were aged at 343, 373, 403 and K. The cast ZA63 and Ca-added alloys were mainly composed of the primary α-Mg and Mg₃₂(Al,Zn)₄₉ phases. The Al₂Ca phase was detected co-existing in the Ca-added alloy. The Ca addition caused the grain refinement and improved hardness after the solid solution treatment compared with the ZA63 alloy even with the trace amount of 0.5 mass% Ca. The peak hardness of the Ca-added alloy aged at each temperature was higher than that of the ZA63 alloy. The microstructures of the ZA63 and Ca-added alloys produced by peak aging at K consist of rod-like, blocky, plate-like and lath-like precipitates. Moreover, the precipitates in the Ca-added alloy are more finely and densely distributed than those in the ZA63 alloy even though the volume fraction of precipitates in the Ca-added alloy estimated by the electrical conductivity during aging at K for longer than 64 h is smaller than that in the ZA63 alloy. The Cliff-Lorimer plots of the EDS results for the β ’₁ phase in the Ca-added alloy aged at K for 1000 h were examined. It was confirmed that the β ’₁ phase in the Ca-added alloy contained Ca atoms, indicating that Ca atoms inside the β ’₁ phase might change the structure and/or composition of precipitates.

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In order to examine microstructure evolution at the interconnection between the Sn-base solder and Au/Ni/Cu multilayer conductor alloys during energization heating, the kinetics of the reactive diffusion between a binary Sn–5 at% Au alloy and pure Ni was experimentally observed at solid-state temperatures. Sandwich (Sn–Au)/Ni/(Sn–Au) diffusion couples were prepared by a diffusion bonding technique, and then isothermally annealed at temperatures of T=, 453 and 473 K for various periods up to 1057 h. During annealing, AuNiSn₈ and Ni₃Sn₄ compound layers are formed along the (Sn–Au)/Ni interface in the diffusion couple. The total thickness of the compound layers is expressed as a power function of the annealing time. The exponent of the power function is close to 0.5 at T=453–473 K, and equal to 0.7 at T= K. Therefore, volume diffusion is the rate-controlling process for the growth of the compound layers at T=453–473 K, but interface reaction contributes to the rate-controlling process at T= K. The growth of the compound layers occurs slower for the reactive diffusion between the Sn–5Au alloy and Ni than for that between Sn and Au, but faster for that between the Sn–5Au alloy and Ni than for that between Sn and Ni.

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The kinetics of the reactive diffusion between a binary Ag–5 at% Pt alloy and Sn was experimentally studied at solid-state temperatures using sandwich Sn/Ag_0.95Pt_0.05/Sn diffusion couples. The diffusion couple was prepared by a diffusion bonding technique and then isothermally annealed at temperatures of T=, 453 and 473 K for various times up to 408 h in an oil bath with silicone oil. During annealing, an intermetallic layer of Ag₃Sn dispersed with fine particles of PtSn₄ is formed at each interface in the diffusion couple. The mean thickness of the intermetallic layer is expressed as a power function of the annealing time. The exponent of the power function takes values around 0.35 at T=–473 K. Thus, the growth of the intermetallic layer is controlled by grain boundary diffusion as well as volume diffusion. The growth rate of the intermetallic layer is greater for the Sn/Ag_0.95Pt_0.05/Sn diffusion couple than for the Sn/Ag/Sn diffusion couple at T=–473 K. However, the temperature dependence of the growth rate shows that the growth rate may be smaller for the Sn/Ag_0.95Pt_0.05/Sn diffusion couple than for the Sn/Ag/Sn diffusion couple at T=393 K. Thus, addition of 5 at% Pt into Ag accelerates the kinetics of the reactive diffusion between Ag and Sn at T>400 K but decelerates the kinetics at T<400 K.

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