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81.
Hirooki Tokoi Kinya Kobayashi Hideaki Nagashima Shuichi Ishizawa Yuji Enomoto 《Electrical Engineering in Japan》2016,194(1):37-47
This paper describes a method of predicting the life span of the dies used in motor manufacture from soft magnetic composites (SMCs). In the present study, a clawtooth motor was used. The method involves performing a stress analysis of a die followed by fatigue testing of test pieces. In the analysis, the SMC was assumed to be in powder form and its yield function was derived by a simple method. In addition to the analysis, we describe a simpler and more effective method in which the properties of the SMC are treated as boundary conditions. In the fatigue tests, we used test pieces that simulated the shape and construction material of the die. To predict the life span of the die, we evaluate the SN diagram, which represents the relationship between the maximum stress and fatigue life with respect to the stress generated in the die. The life expectancy of a new die, which is about 100 cycles of use, is found to agree substantially with its actual life. Furthermore, we explain how to extend the life span of a die to the targeted life span, namely, more than 200,000 cycles of use, by changing its shape to reduce stress. 相似文献
82.
Nishikino M. Tanaka M. Ochi Y. Kishimoto M. Ishino M. Hasegawa N. Kado M. Sukegawa K. Kawachi T. Nagashima K. 《IEEE journal of selected topics in quantum electronics》2004,10(6):1382-1387
We have recently reported the successful development of a fully coherent X-ray laser (XRL) at 13.9 nm by an oscillator-amplifier configuration with two targets. In the experiment, a seed XRL beam from the first target is injected into a plasma amplifier at the second target. The observed XRL beam has full spatial coherence and 0.2 mrad of nearly diffraction-limited divergence. In order to improve the output fluence, the amplification properties of the XRL beam have been investigated using various plasma lengths of the second amplifier target. The output energy has been improved by a factor of ten, increasing the length of the gain region to 10 mm, resulting in about 0.2 /spl mu/J of output energy. 相似文献
83.
Yuki Tanaka Takumi Sako Tatsuhiro Hiraoka Misaki Yamaguchi Masayuki Yamaguchi 《应用聚合物科学杂志》2020,137(46):49516
The structure and rheological properties of binary blends of polycarbonate (PC) and polystyrene (PS) were investigated using various PS samples with different molecular weights, namely PS1k (Mw = 1,000), PS53k (Mw = 53,000), and PS240k (Mw = 240,000). The blends with PS53k and PS240k show phase-separated structures, whereas the blend with PS1k is miscible. The shear viscosity decreases greatly on addition of PS53k and PS240k, especially at high shear rates, which would be a great advantage at processing operations. Because the nonlinear response occurs in the small strain region for multilayered films of PC and PS240k, the origin of the significant viscosity drop for the phase-separated system is interfacial slippage at the phase boundary. 相似文献
84.
Hiromi?YoshidaEmail author Kyoko?Matsuda Yuki?Hirakawa Yoshiyuki?Mizushina 《Journal of the American Oil Chemists' Society》2003,80(7):665-674
To clarify the effects of microwave roasting on the distribution of tocopherols and FA of phospholipids within soybeans, whole
soybeans (Glycine max) were treated by microwave and further evaluted as compared to a raw sample. Tocopherol homologs, measured using HPLC, and
phospholipid profiles, quantified with GC, were determined in the seed coat, the embryonic axis, and selections of cotyledons
separated from three cultivars. The tocopherols were predominantly detected in the axis, followed by the cotyledons, and then
very little in the coat. As much as 25% of the individual tocopherols originally present in the coat were lost at 12 min of
roasting, whereas <25% was lost in the cotyledons and the axis after 20 min of roasting. The greatest rate of phospholipid
loss (P<0.05) was observed in PE, followed by PC and PI, and their changing patterns were more pronounced in the coat than in the
cotyledons or the axis. Thus, tocopherol content and phospholipid profiles change with microwave roasting according to tissue. 相似文献
85.
Kanako Sugawara Toru Yoshida Rena Hirashima Ryoko Toriumi Hotaka Akiyama Yurika Kakuta Yuki Ishige Yasushi Sugano 《International journal of molecular sciences》2021,22(16)
DyP-type peroxidases are a family of heme peroxidases named for their ability to degrade persistent anthraquinone dyes. DyP-type peroxidases are subclassified into three classes: classes P, I and V. Based on its genome sequence, Streptomyces avermitilis, eubacteria, has two genes presumed to encode class V DyP-type peroxidases and two class I genes. We have previously shown that ectopically expressed SaDyP2, a member of class V, indeed has the characteristics of a DyP-type peroxidase. In this study, we analyzed SaDyP1, a member of the same class V as SaDyP2. SaDyP1 showed high amino acid sequence identity to SaDyP2, retaining a conserved GXXDG motif and catalytic aspartate. SaDyP1 degraded anthraquinone dyes, which are specific substrates of DyP-type peroxidases but not azo dyes. In addition to such substrate specificity, SaDyP1 showed other features of DyP-type peroxidases, such as low optimal pH. Furthermore, immunoblotting using an anti-SaDyP2 polyclonal antibody revealed that SaDyP1 and/or SaDyP2 is expressed in mycelia of wild-type S. avermitilis. 相似文献
86.
Kiyofumi Takabatake Masakazu Matsubara Eiki Yamachika Yuki Fujita Yuki Arimura Kazuki Nakatsuji Keisuke Nakano Histoshi Nagatsuka Seiji Iida 《International journal of molecular sciences》2021,22(22)
Background: We investigated and compared the osteogenic potential and bone regeneration capacities of dedifferentiated fat cells (DFAT cells) and adipose-derived stem cells (ASCs). Method: We isolated DFAT cells and ASCs from GFP mice. DFAT cells were established by a new culture method using a mesh culture instead of a ceiling culture. The isolated DFAT cells and ASCs were incubated in osteogenic medium, then alizarin red staining, alkaline phosphatase (ALP) assays, and RT-PCR (for RUNX2, osteopontin, DLX5, osterix, and osteocalcin) were performed to evaluate the osteoblastic differentiation ability of both cell types in vitro. In vivo, the DFAT cells and ASCs were incubated in osteogenic medium for four weeks and seeded on collagen composite scaffolds, then implanted subcutaneously into the backs of mice. We then performed hematoxylin and eosin staining and immunostaining for GFP and osteocalcin. Results: The alizarin red-stained areas in DFAT cells showed weak calcification ability at two weeks, but high calcification ability at three weeks, similar to ASCs. The ALP levels of ASCs increased earlier than in DFAT cells and showed a significant difference (p < 0.05) at 6 and 9 days. The ALP levels of DFATs were higher than those of ASCs after 12 days. The expression levels of osteoblast marker genes (osterix and osteocalcin) of DFAT cells and ASCs were higher after osteogenic differentiation culture. Conclusion: DFAT cells are easily isolated from a small amount of adipose tissue and are readily expanded with high purity; thus, DFAT cells are applicable to many tissue-engineering strategies and cell-based therapies. 相似文献
87.
Biosynthesis of Trehangelin in Polymorphospora rubra K07–0510: Identification of Metabolic Pathway to Angelyl‐CoA 下载免费PDF全文
Dr. Yuki Inahashi Taro Shiraishi Dr. Kaia Palm Prof. Dr. Yoko Takahashi Prof. Dr. Satoshi Ōmura Prof. Dr. Tomohisa Kuzuyama Dr. Takuji Nakashima 《Chembiochem : a European journal of chemical biology》2016,17(15):1442-1447
Trehangelins are trehalose angelates discovered from endophytic actinomycete Polymorphospora rubra K07‐0510. We identified the trehangelin biosynthetic gene cluster, including genes that encode a glycoside hydrolase‐like protein (thgC), α‐amylase (thgD), 3‐ketoacyl‐ACP synthase III (thgI), 3‐ketoacyl‐ACP reductase (thgK), enoyl‐CoA hydratase (thgH) and acyl transferase (thgJ). Heterologous expression of thgH, thgI, thgJ and thgK confirmed the importance of these genes in the biosynthesis of trehangelin A. Enzymatic activity studies showed that ThgI catalyses the condensation of acetyl‐CoA and methylmalonyl‐CoA to 2‐methylacetoacetyl‐CoA (MAA‐CoA), ThgK catalyses NADPH‐dependent reduction of MAA‐CoA to 3‐hydroxy‐2‐methylbutyryl‐CoA (HMB‐CoA) and ThgH catalyses the dehydration of HMB‐CoA to angelyl‐CoA (AN‐CoA). This is the first report on the elucidation of the enzymatic formation of AN‐CoA. 相似文献
88.
Yuki Takeshita Kazuya Takakura Takashiro Akitsu 《International journal of molecular sciences》2015,16(2):3955-3969
We have prepared four new Cu(II) complexes containing valine moieties with imidazole ligands at the fourth coordination sites and examined their photo-induced reactions with TiO2 in order of understanding the reaction mechanisms. Under a nitrogen atmosphere, the intermolecular electron transfer reactions (essentially supramolecular interactions) of these systems, which resulted in the reduction of Cu(II) species to Cu(I) ones, occurred after UV light irradiation. In this study, we have investigated the conditions of the redox reactions in view of substituent effects of aldehyde moieties. The results of cyclic voltammetry (CV) on an rotating ring-disk electrode (RRDE) suggested that the substitution effects and redox potentials were correlated. Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were also performed to simulate the UV–Vis and circular dichroism (CD) spectra; the results revealed a reasonably good correlation between the substituent effects and the highest occupied molecular orbitals and the lowest unoccupied molecular orbitals (HOMO-LUMO) gaps associated with the most intense transition bands. In addition, we summarized the substitution effects of Cu(II) complexes for their corresponding UV light-induced reactions. 相似文献
89.
Noritaka Yonezawa Hideki Murakami Satoru Demura Satoshi Kato Shinji Miwa Katsuhito Yoshioka Kazuya Shinmura Noriaki Yokogawa Takaki Shimizu Norihiro Oku Ryo Kitagawa Makoto Handa Ryohei Annen Yuki Kurokawa Kazumi Fushimi Eishiro Mizukoshi Hiroyuki Tsuchiya 《International journal of molecular sciences》2021,22(4)
We evaluated the abscopal effect of re-implantation of liquid nitrogen-treated tumor-bearing bone grafts and the synergistic effect of anti-PD-1 (programmed death-1) therapy using a bone metastasis model, created by injecting MMT-060562 cells into the bilateral tibiae of 6–8-week-old female C3H mice. After 2 weeks, the lateral tumors were treated by excision, cryotreatment using liquid nitrogen, excision with anti-PD-1 treatment, and cryotreatment with anti-PD-1 treatment. Anti-mouse PD-1 4H2 was injected on days 1, 6, 12, and 18 post-treatment. The mice were euthanized after 3 weeks; the abscopal effect was evaluated by focusing on growth inhibition of the abscopal tumor. The re-implantation of frozen autografts significantly inhibited the growth of the remaining abscopal tumors. However, a more potent abscopal effect was observed in the anti-PD-1 antibody group. The number of CD8+ T cells infiltrating the abscopal tumor and tumor-specific interferon-γ (IFN-γ)-producing spleen cells increased in the liquid nitrogen-treated group compared with those in the excision group, with no significant difference. The number was significantly higher in the anti-PD-1 antibody-treated group than in the non-treated group. Overall, re-implantation of tumor-bearing frozen autograft has an abscopal effect on abscopal tumor growth, although re-implantation of liquid nitrogen-treated bone grafts did not induce a strong T-cell response or tumor-suppressive effect. 相似文献
90.
Tsutomu Tachibana Yuki Nishikawa Nakao Kubo Seiji Takeda 《International journal of molecular sciences》2021,22(1)
Floral organs have evolved from leaves for reproduction, and the morphological analyses help to understand the plant diversity and evolution. Habenaria radiata (syn. Pecteilis radiata) is a terrestrial orchid living in wetlands in Japan, Russia, South Korea, and China. The habitats of this plant in Japan have been reduced because of environmental destruction and overexploitation, and thus it is on the Red List of Japan as a Near Threatened species. One of the three petals of the H. radiata flower is called a lip or labellum, which resembles a flying white bird, egret, or white heron, with its proposed function being to attract pollinators. To understand the diversity of H. radiata plants in different areas, we examined the lip morphology and phylogeny of populations from eight habitats in the Kinki area, Japan. The complex shapes of the lips were quantified and presented as a radar chart, enabling characterization of the morphological difference among populations. Phylogenetic analysis with microsatellite markers that we generated showed the variation of genetic diversity among populations, suggesting the different degrees of inbreeding, outbreeding, and vegetative propagation. Our approach offers a basic method to characterize the morphological and genetic diversity in natural populations. 相似文献