http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Melting and Precision Casting of Ti-6Al-4V Alloy by Use of Electron Beam Furnace
Suzuki, Ken-ichiro,Watakabe, Siro 대한금속재료학회 2003 METALS AND MATERIALS International Vol.9 No.4
For melting and casting of Ti-6A1-4V alloy by use of an electron beam furnace, key technologies have been developed: measurement and control of temperature, amount, and chemical composition of molten pool. Tem- perature in the molten pool was measured by applying three devices; a thermocouple, a two color pyrometer and the rate of vaporization from the molten pool. Temperature measured by an optical pyrometer without influence of plasma by shifting the wave lengths of the light for the optical pyrometry from those of plasma evolved above the molten pool was in a good accordance with that estimated from the vaporization rate. By combining temperatures measured by three methods, the temperature gradient in the molten pool was estimated to be a level of 100 K/cm. In order to derive an empirical equation for the depth of molten pool of various metals, the depth of the molten pool was determined for Ti, Ti-6A1-4V alloy, solar grade Si, low carbon steel, and stainless steel by chemical etching of vertical cross section of an ingot melted and solidified in a skull crucible. Chemical compositions of Ti-6A1-4V alloy melt before casting was adjusted by adding an aluminum block into the pool before pouring, which compensated vaporization loss of Al from the pool surface under high vacuum. Since, a key to settle Al content in the specified range is the yield and distribution of Al in every castparts, influences of operating variables on the yield have been studied by paying attention to rapid temperature change observed immediately after addition of aluminum.
( Suzuki Hirokazu ),( Ken Ichi Yoshida ) 한국미생물 · 생명공학회 2012 Journal of microbiology and biotechnology Vol.22 No.9
We established an efficient transformation method for thermophile Geobacillus kaustophilus HTA426 using conjugative transfer from Escherichia coli of host-mimicking plasmids that imitate DNA methylation of strain HTA426 to circumvent its DNA restriction barriers. Two conjugative plasmids, pSTE33T and pUCG18T, capable of shuttling between E. coli and Geobacillus spp., were constructed. The plasmids were first introduced into E. coli BR408, which expressed one inherent DNA methylase gene (dam) and two heterologous methylase genes from strain HTA426 (GK1380-GK1381 and GK0343-GK0344). The plasmids were then directly transferred from E. coli cells to strain HTA426 by conjugative transfer using pUB307 or pRK2013 as a helper plasmid, pUCG18T was introduced very efficiently (transfer efficiency, 10-5-10-3 recipient-1), pSTE33T showed lower efficiency (10-7-10-6 recipient-1) but had a high copy number and high segregational stability. Methylase genes in the donor substantially affected the transfer efficiency, demonstrating that the host-mimicking strategy contributes to efficient transformation. The transformation method, along with the two distinguishing plasmids, increases the potential of G. kaustophilus HTA426 as a thermophilic host to be used in various applications and as a model for biological studies of this genus. Our results also demonstrate that conjugative transfer is a promising approach for introducing exogenous DNA into thermophiles.
( Suzuki Hirokazu ),( Shunji Takahashi ),( Hiroyuki Osada ),( Ken Ichi Yoshida ) 한국미생물 · 생명공학회 2011 Journal of microbiology and biotechnology Vol.21 No.7
DNA methylation in Streptomyces griseus IFO 13350 was analyzed by high-performance liquid chromatographic analysis and bisulfite-based analysis to reveal two methylation sites, 5`-GC5mCGGC-3` and 5`-GAG5mCTC-3`. The methylation was reconstituted in Escherichia coli by simultaneous expression of S. griseus SGR4675 and S. achromogenes M.SacI. The E. coli cells produced plasmids that mimicked the methylation profile of S. griseus DNA, which was readily introduced into S. griseus. The results of this study raise the possibility of a promising approach to establish efficient transformation in several streptomycetes.
SUZUKI, Toshiyuki,SAKUMOTO, Ryosuke,HAYASHI, Ken-Go,OGISO, Takatoshi,KUNII, Hiroki,SHIROZU, Takahiro,KIM, Sung-Woo,BAI, Hanako,KAWAHARA, Manabu,KIMURA, Koji,TAKAHASHI, Masashi 家畜繁殖硏究所 2018 Journal of Reproduction and Development Vol.64 No.6
<P>Interferon-tau (IFNT), a type I interferon (IFN), is known as pregnancy recognition signaling molecule secreted from the ruminant conceptus during the preimplantation period. Type I IFNs, such as IFN-alpha and IFN-beta, are known to activate cell-death pathways as well as induce apoptosis. In cows, induction of apoptosis with DNA fragmentation is induced by IFNT in cultured bovine endometrial epithelial cells. However, the status of cell-death pathways in the bovine endometrium during the preimplantation period still remains unclear. In the present study, we investigated the different cell-death pathways, including apoptosis, pyroptosis, and autophagy, in uterine tissue obtained from pregnant cows and <I>in vitro</I> cultured endometrial epithelial cells with IFNT stimulation. The expression of <I>CASP7</I>, <I>8,</I> and <I>FADD</I> (apoptosis-related genes) was significantly higher in pregnant day 18 uterine tissue in comparison to non-pregnant day 18 tissue. The expression of <I>CASP4</I>, <I>11,</I> and <I>NLRP3</I> (pyroptosis-related genes) was significantly higher in the pregnant uterus in comparison to non-pregnant uterus. In contrast, autophagy-related genes were not affected by pregnancy. We also investigated the effect of IFNT on the expression of cell-death pathway-related genes, as well as DNA fragmentation in cultured endometrial epithelial cells. Similar to its effects in pregnant uterine tissue, IFNT affected the increase of apoptosis-related (<I>CASP8</I>) and pyroptosis-related genes (<I>CASP11</I>), but did not affect autophagy-related gene expression. IFNT also increased γH2AX-positive cells, which is a marker of DNA fragmentation. These results suggest that apoptosis- and pyroptosis-related genes are induced by IFNT in the pregnant bovine endometrial epithelial cells.</P>