检索结果-南通市图书馆

Journal of Biomedical Science and Engineering 2015年第8期8卷 500-510页

作者： Itaru Takeda masayuki machida Sachiyo Aburatani Department of Biotechnology and Life Science Tokyo University of Agriculture and Technology Naka-cho Koganei Tokyo Japan Biotechnology Research Institute for Drug Discovery National Institute of Advanced Industrial Science and Technology (AIST) Tokyo Waterfront Bio-IT Research Building Aomi Koto-ku Tokyo Japan Bioproduction Research Institute National Institute of Advanced Industrial Science and Technology (AIST) Higashi-nijo Tsukisamu Sapporo Japan

The generation of bioactive products by microbial bioprocesses is important for drug discovery, functional food development, and other beneficial purposes. Many pathways contribute to the production of these bioactive compounds, but important knowledge for improving productivity still remains in hidden pathways. Recently, an abundance of knowledge about metabolic pathways has been accumulated in metabolic pathway databases, such as BioCyc and KEGG. Many by-products are chemically transformed and actually used in other enzymatic reactions. In this work, we developed an algorithm for the reconstruction of a comprehensive genetic pathway model from a known metabolic pathway database. This model considers the interactions of the by-products, in addition to the main products. Furthermore, we developed a method for the construction of a comprehensive pathway model in a specific organism. In this study, we reconstructed a Saccharomyces cerevisiae model. From this model, the pathways among enzymes that contributed to galactose metabolism were explored. Using S. cerevisiae DNA microarray data, the activated pathways were found among the explored pathways.

关键词： Bioinformatics Metabolic Pathway

Exploration of Activated Pathways for Improving Antifungal Agent FR901469 Productivity in Fungal Species No.11243 Using Comprehensive Pathway Model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Biosciences and Medicines 2017年第7期5卷 16-31页

作者： Itaru Takeda Hiroya Itoh Makoto Matsui Takashi Shibata masayuki machida Sachiyo Aburatani Department of Biotechnology and Life Science Tokyo University of Agriculture and Technology Tokyo Japan Biotechnology Research Institute for Drug Discovery National Institute of Advanced Industrial Science and Technology (AIST) Tokyo Japan Astellas Pharma Inc. Tsukuba Biotechnology Research Center Ibaraki Japan Bioproduction Research Institute National Institute of Advanced Industrial Science and Technology (AIST) Sapporo Japan Computational Bio Big-Data Open Innovation Laboratory (CBBD-OIL) Tokyo Japan

Secondary metabolites are important for various industrial applications. The production of secondary metabolites is often improved by the activation of substrate supply pathways for biosynthesis. However, many important pathways have remained unclear. In this study, we explored possible pathways related to substrate supply for the biosynthesis of the antifungal agent FR901469 which is a nonribosomal peptide and a fungal secondary metabolite. To clarify the unknown activated pathways, we utilized the Comprehensive Pathway Model (CPM) which was developed in our previous study. We verified that the overexpression of the hypothetical beta-alanine-aminotransferase (BAL-AT), which was included in the explored pathways, improved the FR901469 productivity. The genes encoding the BAL metabolic enzymes are considered to be important for improving the FR901469 productivity.

关键词： Bioinformatics Metabolic Pathway Model Fungi Secondary Metabolites

Microwave Behavior of α-Fe/Fe_3B/Y_2O_3 Nanocomposites in GHz Range Prepared by Melt-Spun Technique

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2004年第1期22卷 13-16页

作者： Masahiro Itoh Ken-ichi machida Collaborative Research Center for Advanced Science and Technology Collaborative Research Center for Advanced Science and Technology Osaka University 2-1 Yamadaoka Suita Osaka 565-0871 JapanOsaka University 2-1 Yamadaoka Suita Osaka 565-0871 Japan

Nanocomposites α-Fe/Fe 3B/Y 2O 3 were prepared by a melt-spun technique, and the electromagnetic wave absorption properties were measured in the 0 05～20 05 GHz range. Compared with α-Fe/Y 2O 3 composites, the resonance frequency (f r) of α-Fe/Fe 3B/Y 2O 3 shifted to a higher frequency range due to the large anisotropy field (H A) of tetragonal Fe 3B (～0 4 mA·m -1). The relative permittivity (ε r=ε r′-jε r″) was constantly low over the 0 5～10 GHz region, which indicates that the composite powders have a high resistivity (ρ=～100 Ωm). The effective electromagnetic wave absorption (RL<-20 dB) was obtained in a frequency range of 2.7～6.5 GHz on resin composites of 80% (mass fraction) α-Fe/Fe 3B/Y 2O 3 powders, with thickness of 6～3 mm respectively. A minimum reflection loss of -33 dB was observed at 4.5 GHz with an absorber thickness of 4 mm.

关键词： melt-spun nanocomposites electromagnetic wave absorption anisotropy field matching frequency

Crystal Structure of Arabidopsis thaliana Dawdle Forkhead-Associated Domain Reveals a Conserved Phospho-Threonine Recognition Cleft for Dicer-Like 1 Binding

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2013年第4期6卷 1290-1300页

作者： Satoru machida Y.Adam Yuan Department of Biological Sciences and Centre for Bioimaging Sciences National University of Singapore 14 Science Drive 4 Singapore 117543 Singapore Temasek Lifesciences Laboratory National University of Singapore 1 Research Link Singapore 117604 Singapore Mechanobiology Institute National University of Singapore T-lab Building 5A Engineering Drive 1 Singapore 117411 Singapore

Dawdle （DDL） is a microRNA processing protein essential for the development of Arabidopsis. DDL contains a putative nuclear localization signal at its amino-terminus and forkhead-associated （FHA） domain at the carboxyl-termi- nus. Here, we report the crystal structure of the FHA domain of Arabidopsis Dawdle, determined by multiple-wavelength anomalous dispersion method at 1.7-A resolution. DDL FHA structure displays a seven-stranded 13-sandwich architec- ture that contains a unique structural motif comprising two long anti-parallel strands. Strikingly, crystal packing of the DDL FHA domain reveals that a glutamate residue from the symmetry-related DDL FHA domain, a structural mimic of the phospho-threonine, is specifically recognized by the structurally conserved phospho-threonine binding cleft. Consistently with the structural observations, co-immuno-precipitation experiments performed in Nicotiana benthami- ana show that the DDL FHA domain co-immuno-precipitates with DCL1 fragments containing the predicted pThr＋3（lle/ Val/Leu/Asp） motif. Taken together, we count the recognition of the target residue by the canonical binding cleft of the DDL FHA domain as the key molecular event to instate FHA domain-mediated protein-protein interaction in plant miRNA processing.

关键词： Arabidopsis DCL1 Arabidopsis DDL forkhead-associated domain phospho-threonine microRNA processing.

Magnetic Properties of Nd-Fe-B Sintered Magnet Powders Recovered by Yb Metal Vapor Sorption

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2004年第1期22卷 152-156页

作者： Horikawa T Itoh M Suzuki Shunji machida K Collaborative Research Center for Advanced Science and Technology Collaborative Research Center for Advanced Science and TechnologyCollaborative Research Center for Advanced Science and TechnologyCollaborative Research Center for Advanced Science and Technology Osaka University Osaka 565-0871 Japan Osaka University Osaka 565-0871 Japan Osaka University Osaka 565-0871 Japan Osaka University Osaka 565-0871 Japan

Fine ground powders of Nd-Fe-B sintered magnet bulks (particle size=46～125 μm in diameter) were coated and alloyed with Yb metal by sorbing them. A significant recovery of the decreased magnetic properties of the ground powders (remanence B r=～0.95 T, coercivity H cj =～227 kA·m -1 and maximum energy product (BH) max=～48 8 kJ·m -3) was observed in accordance with increasing temperature up to 800 ℃. The sorbing temperature and time for Yb metal vapor were optimized and after heating at 800 ℃ for 90 min and annealing subsequently at 610 ℃ for 60 min, the B r, H cj and (BH) max values were increased to be 0.98 T, 712 kA·m -1 and 173 kJ·m -3, respectively. From the microstructural characterizations of resulting samples by using X-ray diffraction (XRD), scanning electron microscopy (SEM), and electron probe X-ray microanalyzer (EPMA), it is found that the sorbed Yb metal uniformly covers the surface and diffuses to the Nd-rich grain boundary of fine ground powders of Nd-Fe-B sintered magnet bulks forming a (Nd,Yb)Fe 2 phase.

关键词： metal materials Nd 2Fe 14B sintered magnets metal vapor sorption magnetic properties recovery rare earths

Synthesis and luminescent properties of low oxygen contained Eu^(2+)-doped Ca-α-SiAlON phosphor from calcium cyanamide reduction

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2008年第2期26卷 198-202页

作者： PIAO Xianqing Ken-ichi machida Takashi Horikawa Hiromasa Hanzawa Center for Advanced Science and Innovation Osaka University 2-1 Yamadaoka Suita

A new convenient calcium cyanamide （CaCN2） reduction route was developed to synthesize the Eu^2＋ activated Ca-α-SiAION phosphors containing low oxygen content. The luminescence properties of the obtained products were investigated for white LEDs application. The critical Eu^2＋ concentration in various hosts and its effect on the photoluminescence properties were studied. The optimized sample （10at.% Eu^2＋ vs. Ca^2＋） could be efficiently excited by the current GaN/InGaN blue LED chips and provided emission intensity competitive with that of YAG：Ce^3＋（P46-Y3） standard, revealing that this phosphor was a potential candidate for phosphor-converted white LEDs.

关键词： nitride phosphor white LEDs SiAION Eu^2+ CaCN2 rare earths

Synchrotron X-ray diffraction techniques for in situ measurement of hydride formation under several gigapascals of hydrogen pressure

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2014年第36期59卷 5290-5301页

作者： Hiroyuki Saitoh Akihiko machida Katsutoshi Aoki Quantum Beam Science Directorate Japan Atomic Energy Agency Sayo-cho Sayo-gun Hyogo 679-5148 Japan Institute for Materials Research Tohoku University Aoba-kuSendai 980-8577 Japan

The high-pressure technique is a fundamental tool for realizing novel phase transitions, chemical reactions, and other exotic phenomena. Hydrogenation is one example of a high-pressure reaction; at high pressures of several gigapascals, hydrogen becomes chemically active and reacts with metals and alloys to form hydrides. This paper covers a high-pressure study of the hydrogenation process and the synthesis of hydrides using a cubic-type multi-anvil apparatus. The experimental details of a hydrogenation cell assembly, high-temperature and highpressure generation, and an in situ observation technique are presented. These experiments are conducted with the aid of in situ synchrotron radiation X-ray diffraction measurements operated in an energy-dispersive mode in the conventional manner for time-resolved measurements and a newly developed angle-dispersive mode for observation of the crystal growth process during formation of metal hydrides. Two successful cases of high-pressure hydrogenation are presented: aluminum hydride, Al H3, and an aluminum-based alloy hydride, Al2 Cu Hx, which are potential candidates for hydrogen storage materials.

关键词： X射线衍射技术金属氢化物原位测量氢气压力同步加速器同步辐射X射线衍射高压技术晶体生长过程

Background diseases and the number of previous intravitreal aflibercept injections on immediate intraocular pressure increase and vitreous reflux rate in phakic eyes

在线全文

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2024年第3期17卷 545-550页

作者： Tetsuya Muto Shigeki machida Shinichiro Imaizumi Department of Ophthalmology Dokkyo Medical University Saitama Medical CenterKoshigaya 343-8555Japan Imaizumi Eye Hospital Koriyama 963-8877Japan Fukushima Medical University Fukushima 960-1295Japan

●AIM:To evaluate the effect of background diseases and number of previous intravitreal aflibercept injections(IVAIs)on immediate intraocular pressure(IOP)increase and vitreous reflux(VR)rate and to evaluate the correlation of both age and axial length with immediate IOP increase and VR rate.●METHODS:This study included 105 patients with cystoid macular edema secondary to retinal vein occlusion,35 patients with diabetic macular edema,69 patients with neovascular age-related macular degeneration(nAMD),and 12 patients with myopic choroidal neovascularization,which underwent first-time *** correlation of immediate IOP increase and VR rates with the four background diseases was ***,the correlation of age with immediate IOP increase and VR rate as well as correlation of axial length with immediate IOP increase and VR rate were ***,54 patients with nAMD were treated with IVAI>10 times(multiple IVAIs).Moreover,the correlation of immediate IOP increase and VR rates with first-time and multiple IVAIs in nAMD was determined.●RESULTS:The immediate IOP increase(P=0.16)and VR rates(P=0.50)were almost similar among the four background *** immediate postinjection IOP and age,VR rate and age,immediate postinjection IOP and axial length,or VR rate and axial length were not correlated in the four background *** immediate IOP increase(P=0.66)and VR rates(P=0.28)did not significantly differ between first-time and multiple IVAIs in nAMD.●CONCLUSION:Background diseases and number of previous IVAIs have no effect on immediate IOP increase and VR ***,age and axial length have no correlation on immediate IOP increase and VR rate.

关键词： aflibercept intraocular pressure vitreous reflux intravitreal injection

Recycle for Sludge Scrap of Nd-Fe-B Sintered Magnet as Isotropic Bonded Magnet

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2004年第1期22卷 168-171页

作者： Masahiro Itoh Masahiro Masuda Shunji Suzuki Ken-ichi machida Collaborative Research Center for Advanced Science and Technology Collaborative Research Center for Advanced Science and TechnologyCollaborative Research Center for Advanced Science and TechnologyCollaborative Research Center for Advanced Science and Technology Osaka University 2-1 Yamadaoka Suita Osaka 565-0871 Osaka University 2-1 Yamadaoka Suita Osaka 565-0871 Osaka University 2-1 Yamadaoka Suita Osaka 565-0871 Osaka University 2-1 Yamadaoka Suita Osaka 565-0871

The reduction diffusion method was performed for the sludge scrap of Nd-Fe-B sintered magnets with adding Ca metal to recover the oxidized Nd-Fe-B phase. After washing the resultant powders to remove Ca metal component, the powders obtained were recycled as an isotropic magnetic powder by the melt spinning method. The magnetic properties of powders as recycled were inferior, especially for the coercivity value, due to the deletion of rare earth metals during the washing process. The adjustment of metal composition, i.e., the addition of Nd metal, at the melt spinning process improved the magnetic properties to be B r=～0.75 T, H cj=～0.93 mA·m -1, and (BH) max=～91 kJ·m -3. The magnetic properties of the bonded magnets prepared from the composition-adjusted powders were B r=～0.66 T, H cj=～0.92 mA·m -1, and (BH) max=～70 kJ·m -3, which are approximately comparable to the commercially available MQPB boned one (B r=～0.73 T, H cj=～0.79 mA·m -1, and (BH) max=～86 kJ·m -3).

关键词： Nd-Fe-B sintered magnet recycling isotropic Nd-Fe-B bonded magnet melt-spinning method sludge scrap rare earths

On fluorescence imaging:The diffusion equation model and recovery of the absorption coefficient of fluorophores

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2022年第6期65卷 1179-1198页

作者： Jijun Liu Manabu machida Gen Nakamura Goro Nishimura Chunlong Sun School of Mathematics Southeast UniversityNanjing 210096China Institute for Medical Photonics Research Hamamatsu University School of MedicineHamamatsu 431-3192Japan Department of Mathematics Hokkaido UniversitySapporo 060-0810Japan Research Institute for Electronic Science Hokkaido UniversitySapporo 060-0810Japan

To quantify fluorescence imaging of biological tissues,we need to solve an inverse problem for the coupled radiative transfer equations which describe the excitation and emission fields in biological *** begin by giving a concise mathematical argument to derive coupled diffusion equations with the Robin boundary condition as an approximation of the radiative transfer *** by using this coupled system of equations as a model for the fluorescence imaging,we have a nonlinear inverse problem to identify the absorption coefficient in this *** associated linearized inverse problem is to ignore the absorbing effect on the excitation *** firstly establish the estimates of errors on the excitation field and the solution to the inverse problem,which ensures the reasonability of the model approximation *** numerical verification is presented to show the validity of such a linearizing process ***,based on the analytic expressions of excitation and emission fields,the identifiability of the absorption coefficient from the linearized inverse problem is rigorously analyzed for the absorption coefficient in the special form,revealing the physical difficulty of the3-dimensional imaging model by the back scattering diffusive system.

关键词： fluorescence imaging diffusion equation inverse problem linearization error estimates identifiability