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11.
Takuya Ito Dr. Niran Roongsawang Dr. Norifumi Shirasaka Dr. Wanli Lu Patricia M. Flatt Dr. Noer Kasanah Dr. Cristobal Miranda Dr. Taifo Mahmud Prof. Dr. 《Chembiochem : a European journal of chemical biology》2009,10(13):2253-2265
Pactamycin is an aminocyclopentitol‐derived natural product that has potent antibacterial and antitumor activities. Sequence analysis of an 86 kb continuous region of the chromosome from Streptomyces pactum ATCC 27456 revealed a gene cluster involved in the biosynthesis of pactamycin. Gene inactivation of the Fe‐S radical SAM oxidoreductase (ptmC) and the glycosyltransferase (ptmJ), individually abrogated pactamycin biosynthesis; this confirmed the involvement of the ptm gene cluster in pactamycin biosynthesis. The polyketide synthase gene (ptmQ) was found to support 6‐methylsalicylic acid (6‐MSA) synthesis in a heterologous host, S. lividans T7. In vivo inactivation of ptmQ in S. pactum impaired pactamycin and pactamycate production but led to production of two new pactamycin analogues, de‐6‐MSA‐pactamycin and de‐6‐MSA‐pactamycate. The new compounds showed equivalent cytotoxic and antibacterial activities with the corresponding parent molecules and shed more light on the structure–activity relationship of pactamycin. 相似文献
12.
Directed Vertical Diffusion of Photovoltaic Active Layer Components into Porous ZnO‐Based Cathode Buffer Layers 下载免费PDF全文
Jia‐Jhen Kang Tsung‐Yu Yang Yi‐Kang Lan Wei‐Ru Wu Chun‐Jen Su Shih‐Chang Weng Norifumi L. Yamada An‐Chung Su U‐Ser Jeng 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(15)
Cathode buffer layers (CBLs) can effectively further the efficiency of polymer solar cells (PSCs), after optimization of the active layer. Hidden between the active layer and cathode of the inverted PSC device configuration is the critical yet often unattended vertical diffusion of the active layer components across CBL. Here, a novel methodology of contrast variation with neutron and anomalous X‐ray reflectivity to map the multicomponent depth compositions of inverted PSCs, covering from the active layer surface down to the bottom of the ZnO‐based CBL, is developed. Uniquely revealed for a high‐performance model PSC are the often overlooked porosity distributions of the ZnO‐based CBL and the differential diffusions of the polymer PTB7‐Th and fullerene derivative PC71BM of the active layer into the CBL. Interface modification of the ZnO‐based CBL with fullerene derivative PCBE? OH for size‐selective nanochannels can selectively improve the diffusion of PC71BM more than that of the polymer. The deeper penetration of PC71BM establishes a gradient distribution of fullerene derivatives over the ZnO/PCBE‐OH CBL, resulting in markedly improved electron mobility and device efficiency of the inverted PSC. The result suggests a new CBL design concept of progressive matching of the conduction bands. 相似文献
13.
Yoshihiro Kamada Hideki Fujii Hironobu Fujii Yoshiyuki Sawai Yoshinori Doi Naofumi Uozumi Kayo Mizutani Maaya Akita Motoya Sato Sachiho Kida Noriaki Kinoshita Nobuhiro Maruyama Takayuki Yakushijin Masanori Miyazaki Hisao Ezaki Naoki Hiramatsu Yuichi Yoshida Shinichi Kiso Yasuharu Imai Norifumi Kawada Tetsuo Takehara Eiji Miyoshi 《Proteomics. Clinical applications》2013,7(9-10):648-656
14.
Nabeta M Abe Y Kagawa L Haraguchi R Kito K Ueda N Sugita A Yokoyama M Kusanagi Y Ito M 《Proteomics. Clinical applications》2009,3(10):1201-1210
Diagnosis of endometriosis needs invasive maneuvers. New serum marker that possesses both high sensitivity and high specificity has long been desired. To establish novel serum marker for endometriosis, serum autoantibodies (autoAbs) were investigated using proteomic approach. AutoAbs in sera of endometriotic patients and healthy controls were analyzed using a mesothelial cell line, 2-DE and Western blotting. Proteins in reacted spots were identified using MALDI TOF-MS with MASCOT analysis. ELISAs were established using recombinant proteins and autoAb-titers were estimated in sera of endometriotic patients, disease and healthy controls. Several autoAbs were identified. Anti-α-enolase (Eno1)-autoAb levels in endometriotic patients were significantly elevated compared with both healthy and disease controls. Sensitivity and specificity of serum anti-Eno1-autoAb was nearly comparable to serum CA125. When anti-Eno1-autoAb and CA125 assays were combined, diagnostic sensitivity and accuracy improved. Serum anti-Eno1-autoAb can be a new serum endometriotic marker and it is useful as a supplement assay for CA125. This study validates further clinical evaluation of this novel marker. 相似文献
15.
Three-phase squirrel cage induction motors (IM) have been used in all types of industry, because of their robustness and simplicity of structure, low cost, and ease of maintenance. Due to the resultant air gap flux wave, an IM produces electromagnetic vibration and noise more or less regardless of the slot combination. Recently, reduction of electromagnetic vibration and noise has become important from the standpoint of environmental improvement. Vibration caused by an IM at no-load has been studied for many years and its basic factors have been analyzed. However, electromagnetic vibration under load has not been analyzed sufficiently. Since vibration under load conditions is affected by load and installation, analysis of this vibration is a rather difficult task. But study of the electromagnetic vibration of the motor itself under load is basically the most important item. This paper clarifies, theoretically and experimentally, the causes and characteristics of the electromagnetic vibration of an IM under load conditions. First, general equations are derived for the dominant electromagnetic force waves that produce electromagnetic vibration. Causes and vibration modes are clearly classified and a theoretical analysis provides a basic concept for electromagnetic vibrations. Second, electromagnetic vibrations for various loads are measured taking the effect of natural frequency of the motor into consideration. The measured data are classified and analyzed in detail, based on the proposed theory. © Scripta Technica, Inc. Electr Eng Jpn, 120(4): 81–89, 1997 相似文献
16.
Fumihiko Akutsu Mari Inoki Nobuyoshi Daicho Yoshio Kasashima Norifumi Shiraishi Kenji Marushima 《应用聚合物科学杂志》1998,69(9):1737-1741
2,3-Bis(4-aminophenyl)quinoxaline (1a), 2,3-bis(4-aminophenyl)-6-methylquinoxaline (1b), and 5,6-bis(4-aminophenyl)-3-(2-pyridyl)-1,2,4-triazine (2) were studied as curing agents of epoxy resins. The exotherms on differential scanning calorimetry thermograms of the mixtures of diglycidyl ether of bisphenol A (DGEBA) with 1a, 1b, and 2 were observed at higher temperatures than that of the mixture of DGEBA with a commercially used diamine, for example, 4,4′-diaminodiphenylsulfone (DDS). However, the epoxy resin cured with 1a (EP-1a) showed higher tensile strength to stainless steel at 20°C than that cured with DDS, and the high tensile strength of EP-1a was maintained even at 180°C. The epoxy resin cured with 1b or 2 also possessed higher tensile strength at 20°C than that cured with DDS, but the high tensile strength lowered somewhat at 120°C. Using diamines 1a, 1b, and 2 as a curing agent improved heat distortion temperatures of the cured epoxy resins. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 69: 1737–1741, 1998 相似文献
17.
A water model study was carried out to understand the behavior of a molten steel and Ar gas two-phase jet issuing out of a
submerged entrance nozzle in continuous casting modls. A mixture of water and air was injected horizontally from a circular
pipe settled flush with the narrow face of a mold having a rectangular cross section. The water-air two-phase jet thus generated
was pulled upward through the effect of buoyancy force acting on air bubbles. The deflection of the jet in the upward direction
was correlated by introducing a velocity scale, which could characterize the upward moving velocity of the jet. The mean velocity
and turbulence components of water flow were measured with a laser Doppler velocimeter. Empirical equations were proposed
for predicting the two velocity components. 相似文献
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20.
Hiroya Kitahata Kiyoharu Tadanaga Tsutomu Minami Norifumi Fujimura Taichiro Ito 《Journal of the American Ceramic Society》1998,81(5):1357-1360
YMnO3 thin films with Y/Mn ratios from 1.00/1.05 to 1.00/0.90 were prepared by dip-coating from solution, in which starting materials were refluxed, and the effects of the Y/Mn ratio on the structure and dielectric properties of YMnO3 thin films were investigated. XRD measurements indicated that the films with the Y/Mn ratios in this study were a single phase of polycrystalline YMnO3 . The lattice constants along the a -axis and c -axis lengthened with an increase in the Y/Mn ratio. FE-SEM micrographs of the films showed that the surface of the films became smoother and denser with an increase in the Y/Mn ratio. YMnO3 thin films with good dielectric properties were obtained with an Y/Mn ratio of 1.00/0.90, which gave the smoothest and densest microstructure and the smallest leakage current. 相似文献