649 results on '"Takeshi Yamazaki"'
Search Results
202. Phenotypic Relationship between Lactation Persistency and Change in Body Condition Score in First-lactation Holstein Cows
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Naoko Sugawara, Kenji Togashi, Youji Sasai, Hisato Takeda, Akiko Nishiura, and Takeshi Yamazaki
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medicine.medical_specialty ,Ice calving ,Biology ,Endocrinology ,Animal science ,Milk yield ,medicine.anatomical_structure ,Body condition score ,Internal medicine ,Lactation ,medicine ,Animal Science and Zoology ,Curve shape ,sense organs ,Food Science - Abstract
We examined the correlations between lactation curve shape, including persistency and changes in body condition score (BCS) during early-stage (0 to 30 days in milk (DIM)), nadir-stage (31 to 90 DIM), and late-stage (91 to 240 DIM) lactation in 191 first-lactation cows. Data used were first-parity BCS records, scored twice every month after calving, and daily milk yields. Individual lactation curves were depicted by the Wilmink function. Lactation persistency was defined as the difference in estimated milk yields between 240 DIM and 60 DIM. Changes in BCSs in the early and late stages were defined as linear regression coefficients. There were no significant correlations between traits for lactation curve shape and change in BCS in early-stage lactation. Peak yield and total milk yield were negatively correlated with BCSs in nadir- and late-stage lactation and with BCS change in late-stage lactation, suggesting that cows with high lactation yields had low body reserves and health status in mid- to late lactation and had delayed recovery of body reserves. Lactation persistency was positively correlated with change in BCS in late-stage lactation, suggesting that cows with high lactation persistency tended to be healthy and to recover their body reserves well in late lactation. more...
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- 2011
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203. Environmental enrichment alters gene expression of steroidogenic enzymes in the rat hippocampus
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Eiji Munetsuna, Suguru Kawato, Takeshi Yamazaki, Yuya Sakimoto, Shogo Sakata, Yasushi Hojo, Atsuhiko Ishida, and Minoru Hattori
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Male ,Restraint, Physical ,medicine.medical_specialty ,3-Hydroxysteroid Dehydrogenases ,Neuroactive steroid ,Mrna expression ,Hippocampus ,Dehydrogenase ,Pregnanolone ,Biology ,Random Allocation ,Steroidogenic enzymes ,chemistry.chemical_compound ,Endocrinology ,3-Oxo-5-alpha-Steroid 4-Dehydrogenase ,Internal medicine ,Gene expression ,medicine ,Animals ,RNA, Messenger ,Rats, Wistar ,Environmental enrichment ,Reverse Transcriptase Polymerase Chain Reaction ,Body Weight ,Allopregnanolone ,Organ Size ,Rats ,Gene Expression Regulation ,chemistry ,Animal Science and Zoology - Abstract
Neuroactive steroids are synthesized in the central and peripheral nervous systems. The purpose of this study was to analyze the effects of environmental enrichment on neuroactive steroidogenesis in the rat hippocampus. Environmental enrichment rats were housed in a group of nine in a large cage and three groups of pair-housed rats were housed in a standard cage for 8 weeks. The levels of mRNAs for steroidogenic enzymes and proteins in hippocampus were quantified by real-time RT-PCR. Environmental enrichment increased the mRNA expression levels of 5α-reductase-1 and 3α-hydroxysteroid dehydrogenase, which catalyze synthesis of allopregnanolone from progesterone. Hence, environmental enrichment appears to affect allopregnanolone synthesis. more...
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- 2011
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204. Roles of Eastern Siberian Mountain Ranges in Precipitation -Verkhoyansk, Dzhugdzhur and Stanovoy Mountain Ranges
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Takeshi Yamazaki, Ryuhei Yoshida, and Masahiro Sawada
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Atmospheric Science ,geography ,geography.geographical_feature_category ,Climatology ,Elevation ,Humidity ,Precipitation ,Physical geography ,Structural basin ,human activities ,Geology ,Mountain range - Abstract
Precipitation amounts of three Lena mountain ranges (Verkhoyansk, Dzhugdzhur and Stanovoy) were investigated using numerical simulations for three months. First, we examined the precipitation distribution in eastern Siberia using routine station data. A north-south precipitation gradient was found, with the greatest precipitation in a southern area, and 47% of precipitation occurring in June, July, and August.To isolate the roles of the three Lena mountain ranges in determining precipitation, especially the north-south precipitation gradient, we conducted mountain removal experiments to examine differences in precipitation from the results of a real topography experiment. Results show that the Verkhoyansk (northeast of the Lena Basin) and Dzhugdzhur Mountain Range (southeast) had a weak effect on the north-south precipitation gradient. It was caused by relatively low specific humidity for Verkhoyansk and low elevation for Dzhugdzhur mountain range. The Stanovoy mountain range (south) exhibited a strong effect with higher specific humidity and elevation. Thus Stanovoy mountain range has the most contribution to north-south precipitation gradient among three Lena mountain ranges. more...
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- 2011
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205. Examination of Original Plant of Mulberry Bark Extract, a Natural Food Additive, Based on Composition of the Constituents
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Atsuko Tada, Toshio Fukai, Takumi Akiyama, Akio Koyama, Kyoko Ishizuki, Takeshi Yamazaki, and Yoko Kawamura
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food.ingredient ,Traditional medicine ,Plant Extracts ,Food additive ,Ms analysis ,Morus bombycis ,General Medicine ,Biology ,Japanese Pharmacopoeia ,food ,Tandem Mass Spectrometry ,Natural food ,visual_art ,Botany ,Mori Cortex ,visual_art.visual_art_medium ,Food Additives ,Composition (visual arts) ,Bark ,Morus ,Chromatography, Liquid - Abstract
Mulberry bark extract, a natural food additive, is described as a "root bark extract from Morus bombycis" (Japanese name: Yamaguwa) in the Notice (1996) relating to existing food additives used in Japan. The results of analyses by LC/UV and LC/MS suggested that the Mulberry bark extract products that were tested were actually made from the root bark of Morus alba (Japanese name: Maguwa) or its hybrid species, because the compositions of the constituents in the products are more similar to those in the extracts of the dried root bark of M. alba and hybrid species that are cultivated in Japan than to those of M. bombycis. In addition, the constituents of the food additive products were different from those of the natural medicine Mori Cortex products ('Souhakuhi' in Japanese) made from the root bark of mulberry grown in China, and which is described as being derived from M. alba in the Japanese pharmacopoeia. These results were also corroborated by Principal Component Analysis using the peak areas of LC/MS analysis as explanatory variables. After this study, it was decided that Mulberry bark extract is one of the existing food additives that should be excluded from the list this year in Japan. more...
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- 2011
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206. Analysis of Thickening Polysaccharides by the Improved Diethyldithioacetal Derivatization Method
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Takumi Akiyama, Takeshi Yamazaki, and Ken-ichi Tanamoto
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chemistry.chemical_classification ,Guar gum ,Chromatography ,food.ingredient ,Karaya Gum ,Tragacanth ,Monosaccharides ,General Medicine ,Polysaccharide ,Glucuronic acid ,Galactans ,Gas Chromatography-Mass Spectrometry ,Mannans ,Gum Arabic ,chemistry.chemical_compound ,Hydrolysis ,food ,chemistry ,Polysaccharides ,Plant Gums ,Gum arabic ,Monosaccharide ,Food Additives - Abstract
The identification test for thickening polysaccharides containing neutral saccharides and uronic acids was investigated by GC analysis of constituent monosaccharides. The reported method, in which monosaccharides were converted to diethyldithioacetal derivatives with ethanethiol followed by trimethylsilylation, was improved in terms of operability and reproducibility of GC/MS analysis. The suitability of the improved diethyldithioacetal derivatization method was determined for seven thickening polysaccharides, i.e., carob bean gum, guar gum, karaya gum, gum arabic, gum ghatti, tragacanth gum and peach gum. The samples were acid-hydrolyzed to form monosaccharides. The hydrolysates were derivatized and analyzed with GC/FID. Each sugar derivative was detected as a single peak and was well separated from others on the chromatograms. The amounts of constituent monosaccharides in thickening polysaccharides were successfully estimated. Seven polysaccharides were distinguished from each other on the basis of constituent monosaccharides. Further examination of the time period of hydrolysis of polysaccharides using peach gum showed that the optimal times were not the same for all monosaccharides. A longer time was needed to hydrolyze glucuronic acid than neutral saccharides. The findings suggest that hydrolysis time may sometimes affect the analytical results on composition of constituent monosaccharides in polysaccharides. more...
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- 2011
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207. Application of 1H-NMR spectroscopy to validation of berberine alkaloid reagents and to chemical evaluation of Coptidis Rhizoma
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Naoki Sugimoto, Takeshi Yamazaki, Takamitsu Yoshida, Hajime Mizukami, Keiko Hasada, Akito Nagatsu, and Tetsuji Nishimura
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Coptisine ,endocrine system ,Magnetic Resonance Spectroscopy ,Chromatography ,Berberine ,Molecular Structure ,Plant Extracts ,Chemistry ,organic chemicals ,Potassium hydrogen phthalate ,Alkaloid ,Berberine Alkaloids ,Palmatine ,Crude drug ,complex mixtures ,High-performance liquid chromatography ,chemistry.chemical_compound ,Certified reference materials ,Molecular Medicine ,heterocyclic compounds ,Chromatography, High Pressure Liquid ,Coptis - Abstract
Berberine, palmatine, and coptisine are major pharmacologically active protoberberine alkaloids in Coptidis Rhizoma, and have been used as indices for chemical evaluation of the crude drug. (1)H-NMR spectroscopy was applied to determination of purities of commercial reagents of protoberberine alkaloids. The purities of the alkaloids were calculated from the ratios of the intensities of the H-13 singlet signal at about δ 8.7 ppm of target protoberberine alkaloids to integration of a hexamethyldisilane (HMD) signal at 0 ppm. The concentration of HMD was corrected with SI traceability using potassium hydrogen phthalate of certified reference material (CRM) grade. The purity of the reagent estimated by the (1)H-NMR was, in general, lower than that claimed by the manufacturer, leading to over-estimation of the alkaloid contents of Coptidis Rhizoma when determined by HPLC. The present quantitative (1)H-NMR method was also applicable to direct determination of protoberberine alkaloid contents in Coptidis Rhizoma. more...
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- 2010
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208. Spatial Decomposition of Solvation Free Energy Based on the 3D Integral Equation Theory of Molecular Liquid: Application to Miniproteins
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Andriy Kovalenko and Takeshi Yamazaki
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Models, Molecular ,Entropy ,Implicit solvation ,Molecular Conformation ,Amino acid residues ,Quantitative Structure-Activity Relationship ,Mini-proteins ,Spatial decompositions ,3-D space ,Computational chemistry ,Materials Chemistry ,Integral equations ,Molecular liquids ,Alanine ,Chemistry ,quantitative structure activity relation ,Direct correlation functions ,Surfaces, Coatings and Films ,Solutions ,Excluded volume ,symbols ,Thermodynamics ,van der Waals force ,Oligopeptides ,Distribution functions ,Integral-equation theory ,Protein molecules ,Solvation thermodynamics ,Chignolin ,Entropy (classical thermodynamics) ,symbols.namesake ,Computer Simulation ,Physical and Theoretical Chemistry ,Three dimensional ,Quantitative structure-activity relationships ,Solvation ,Proteins ,Water ,Atomistic resolution ,1-Octanol ,Models, Theoretical ,Conformational change ,Integral equation ,Protein thermodynamics ,Solvation shell ,Distribution function ,Energy Transfer ,Solubility ,Mutation - Abstract
We propose the method of spatial decomposition analysis (SDA) based on three-dimensional integral equation (3D-IE) theory of molecular liquids to study and decompose the thermodynamics of proteins in solution into atomic level contributions. The 3D-IE theory maps the solvation thermodynamic properties, such as the solvation free energy and solvation entropy, onto the 3D space around the solute, including the excluded volume of the solute macromolecule, with the elementary volume contributions expressed in terms of the 3D total and direct correlation functions. The SDA thus breaks down the thermodynamic quantity into partial contributions of the solute fragments (functional groups or residues) by applying the proximity criterion to the 3D-IE mapping onto both the solvation shell outside the solute macromolecule and its excluded volume inside the van der Waals cores, the latter giving a major contribution to the solvation thermodynamics. This is distinct from the previous use of the proximity criterion applied to the 3D distribution functions in the solvation shell only. As SDA does not require perturbing the protein molecule to extract the contributions from the constituent residues, it can become an alternative to the computational "alanine scanning approach". For illustration, we apply SDA to four miniproteins composed of 10-28 amino acid residues (chignolin, CLN025, Trp-cage, and FSD-1) and decompose their solvation free energy into the partial contributions of each residue. The present results show that SDA is capable of detecting a change in the protein thermodynamics due to mutations and local conformational changes. Furthermore, the SDA exhibits a convincing consistency with the experimental values of the whole-residue transfer free energies from water to 1-octanol. Thus, the SDA provides a meaningful decomposition of the protein thermodynamics which can bear a comparison with experimental measurements and therefore can serve as a valuable sensitive tool to analyze the protein thermodynamics at the atomistic resolution level. We envision that the SDA may also serve as a tool for quantitative structure-activity relationships (QSAR) to correlate and predict various solute properties in a fragment-based manner. © Published 2010 by the American Chemical Society. more...
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- 2010
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209. S-Wave πK Scattering Length in 2+1 Flavor Lattice QCD
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Kiyoshi Sasaki, Makoto Oka, Takeshi Yamazaki, and N. Ishizuka
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Physics ,Quantum chromodynamics ,Particle physics ,Chiral perturbation theory ,Physics and Astronomy (miscellaneous) ,Quantum electrodynamics ,QCD vacuum ,S-wave ,Lattice field theory ,Scattering length ,Lattice QCD ,Lattice model (physics) - Published
- 2010
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210. FP106PERIODICAL REPEATED RITUXIMAB ADMINISTRATIONS IN CHILDREN WITH REFRACTORY NEPHROTIC SYNDROME; TWO YEARS PROSPECTIVE OBSERVATIONAL STUDY
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Takayuki Okamoto, Yasuyuki Sato, Takeshi Yamazaki, Asako Hayashi, Toshiyuki Takahashi, and Tadashi Ariga
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Transplantation ,Pediatrics ,medicine.medical_specialty ,Refractory ,Nephrology ,business.industry ,Medicine ,Observational study ,Rituximab ,business ,medicine.disease ,Nephrotic syndrome ,medicine.drug - Published
- 2018
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211. Structural Water Drives Self-assembly of Organic Rosette Nanotubes and Holds Host Atoms in the Channel
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Hicham Fenniri, Andriy Kovalenko, and Takeshi Yamazaki
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Models, Molecular ,Nanotubes ,Surface Properties ,Chemistry ,Hydrogen bond ,Static Electricity ,Solvation ,Water ,Nanotechnology ,Molecular orbital theory ,Atomic and Molecular Physics, and Optics ,Models, Chemical ,Chemical physics ,Monolayer ,Solvents ,Molecule ,Adsorption ,Wetting ,Self-assembly ,Physical and Theoretical Chemistry ,Solvent effects - Abstract
We reveal how water solvent determines the self-assembly pathway and stability of organic rosette nanotubes (RNTs) and show their possible functions, using three-dimensional molecular theory of solvation (a.k.a. 3D-RISM). Structural water molecules penetrate the pockets on the RNT outer surface, form a wetting monolayer in the RNT channel and bridge RNT rosettes. We predict that the inner water shell might stabilize rare gas atoms inside the RNT channel, and envision molecular devices with RNT channels transporting water or holding guest molecules for targeted delivery. more...
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- 2010
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212. Development of High Accurate and High-Speed, Worm Form Rolling Technology with V Character Wedge Die
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Takeshi Yamazaki, Hiroyuki Watase, Toshikatsu Nakashima, Koji Odani, and Takayoshi Sasaki
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Engineering drawing ,Engineering ,Character (mathematics) ,business.product_category ,Mechanics of Materials ,business.industry ,Mechanical Engineering ,Die (manufacturing) ,General Materials Science ,Development (differential geometry) ,business ,Wedge (mechanical device) - Published
- 2010
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213. Identification Methods of Terpenoid Gum Bases Using TLC and GC/MS
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Takeshi Yamazaki, Naoki Sugimoto, Ayumi Hayashi, Young Sook Yun, Ken-ichi Tanamoto, Yoko Kawamura, Akira Kunugi, Takumi Akiyama, and Atsuko Tada
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Identification methods ,Chromatography ,Terpenes ,Chemistry ,Rosin ,General Medicine ,Gas Chromatography-Mass Spectrometry ,Terpenoid ,Chewing Gum ,Triterpenoid ,Benzoin Gum ,medicine ,Organic chemistry ,Food Additives ,Chromatography, Thin Layer ,Gas chromatography–mass spectrometry ,Food Analysis ,Resins, Plant ,medicine.drug - Abstract
Simple chromatographic methods were applied to terpenoid resins used as gum bases. Five triterpenoid resins, mastic, dammar resin, olibanum, benzoin gum and elemi resin, and two diterpenoid resins, rosin and copal resin, were separated with normal-phase TLC. Characteristic patterns were observed for all resins. Different samples of the same resin gave identical patterns. The TLC method is a candidate for a simple identification test for terpenoids resins. Samples were then methyl-esterified and analyzed with GC/MS. All resins exhibited characteristic chromatograms for total ion current. Major constituents of all resins were detected. Unique constituents that can be used as indicators were found in every resin. Therefore, GC/MS of methyl-esterified terpenoid resins is a valuable identification method. more...
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- 2010
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214. Absolute Quantification of Carminic Acid in Cochineal Extract by Quantitative NMR
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Takeshi Saito, Atsuko Tada, Takako Suematsu, Takeshi Yamazaki, Sumio Ito, Yuuichi Yoshida, Kumiko Shimizu, Reiji Kubota, Tetsuji Nishimura, Toshihide Ihara, Kazunori Arifuku, Naoki Sugimoto, Maiko Tahara, and Yoko Kawamura more...
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chemistry.chemical_classification ,Cochineal ,Magnetic Resonance Spectroscopy ,Chromatography ,Carminic acid ,biology ,Potassium hydrogen phthalate ,Food Coloring Agents ,Salt (chemistry) ,General Medicine ,Nuclear magnetic resonance spectroscopy ,Mass spectrometry ,biology.organism_classification ,Carmine ,chemistry.chemical_compound ,Certified reference materials ,chemistry ,Coloring Agents ,Quantitative analysis (chemistry) ,Chromatography, High Pressure Liquid - Abstract
A quantitative NMR (qNMR) method was applied for the determination of carminic acid. Carminic acid is the main component in cochineal dye that is widely used as a natural food colorant. Since several manufacturers only provide reagent-grade carminic acid, there is no reference material of established purity. To improve the reliability of analytical data, we are developing quantitative nuclear magnetic resonance (qNMR), based on the fact that the intensity of a given NMR resonance is directly proportional to the molar amount of that nucleus in the sample. The purities and contents of carminic acid were calculated from the ratio of the signal intensities of an aromatic proton on carminic acid to nine protons of three methyl groups on DSS-d6 used as the internal standard. The concentration of DSS-d6 itself was corrected using potassium hydrogen phthalate, which is a certified reference material (CRM). The purities of the reagents and the contents of carminic acid in cochineal dye products were determined with SI-traceability as 25.3-92.9% and 4.6-30.5% based on the crystalline formula, carminic acid potassium salt trihydrate, which has been confirmed by X-ray analysis. The qNMR method does not require a reference compound, and is rapid and simple, with an overall analysis time of only 10 min. Our approach thus represents an absolute quantitation method with SI-traceability that should be readily applicable to analysis and quality control of any natural product. more...
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- 2010
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215. Relationship between the lactation curve and udder disease incidence in different lactation stages in first-lactation Holstein cows
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Akiko Nishiura, Takeshi Yamazaki, Hisato Takeda, and Kenji Togashi
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High rate ,animal structures ,Incidence (epidemiology) ,food and beverages ,General Medicine ,Biology ,Milk production ,fluids and secretions ,medicine.anatomical_structure ,Milk yield ,Animal science ,Lactation ,Long period ,medicine ,Udder ,General Agricultural and Biological Sciences - Abstract
We examined the relationships between the shape of the first parity lactation curve and udder disease incidence at different stages of lactation in 538 Holstein cows. Data used were first-parity daily milk yields and treatment records. Each cow was classified according to whether or not it had had udder disease at least once over the whole lactation period or in one of three stages within the lactation period. We then examined the differences in the shapes of the lactation curves between the disease incidence and non-incidence group in each stage. Cows that had high rates of increase in milk yield and high milk yields in early lactation were predisposed to udder disease afterwards. Cows with high milk production over a long period but with low lactation persistency were predisposed to udder disease after the peak of lactation. There was no difference in total milk yield between incidence and non-incidence groups in all stages, suggesting that, for a comparable level of lactation, cows without udder diseases have flatter lactation curves. more...
- Published
- 2009
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216. Ion Solvation in a Water−Urea Mixture
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G. N. Patey, Vladimir V. Murashov, Andriy Kovalenko, and Takeshi Yamazaki
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Ions ,Physics::Biological Physics ,Quantitative Biology::Biomolecules ,Chemistry ,Implicit solvation ,Solvation ,Water ,Thermodynamics ,Molecular Dynamics Simulation ,Integral equation ,Surfaces, Coatings and Films ,Ion ,Molecular dynamics ,chemistry.chemical_compound ,Solvation shell ,Computational chemistry ,Materials Chemistry ,Urea ,Free energies ,Physical and Theoretical Chemistry - Abstract
We employ molecular dynamics simulations and the reference interaction site model (RISM) integral equation theory to study the solvation structure and solvation thermodynamics of the transfer process from water to a water-urea mixture. Simple positive and negative ions together with uncharged species of the same size are used as crude models for the hydrophilic and hydrophobic groups of a protein. We find that urea preferentially solvates positively charged species. The solvation free energies obtained indicate that larger solutes favor the transfer from water to a water-urea mixture. The decomposition of the transfer free energy into the energetic and entropic terms shows that the energetic part is much larger than the entropic one and tends to dominate the transfer process, supporting the direct mechanism of urea-denaturation. In addition, the effect of urea on the water liquid structure is discussed from the viewpoint of solvation entropy. more...
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- 2009
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217. Supramolecular Synthesis of Solid-State Tapes Through Molecular Facial Self-Recognition
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Gabor Borzsonyi, Hicham Fenniri, Andriy Kovalenko, Takeshi Yamazaki, Martins S. Oderinde, Robert McDonald, Bo-Liang Deng, and Rachel L. Beingessner
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chemistry.chemical_classification ,Hydrogen bond ,Organic Chemistry ,Supramolecular chemistry ,Solid-state ,Self recognition ,Biochemistry ,Catalysis ,Inorganic Chemistry ,Supramolecular polymers ,Crystallography ,chemistry ,Drug Discovery ,X-ray crystallography ,Pi interaction ,Physical and Theoretical Chemistry - Abstract
Four heterocyclic compounds are presented which exhibit specific self-recognition of identical Donor–Acceptor (D–A) H-bonding arrays, resulting in solid-state tapes with the same, but anti-parallel functional-group distribution on opposite sides. A detailed X-ray-crystallographic analysis of these supramolecular structures is described. more...
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- 2009
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218. Changes in shell gathering in an early agricultural society at the head of Ise Bay, Japan
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Sen-ichi Oda and Takeshi Yamazaki
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Fishery ,Archeology ,Geography ,Oceanography ,Common species ,biology ,Range (biology) ,Bronze Age ,Meretrix lusoria ,biology.organism_classification ,Bay ,Head (geology) - Abstract
We examined changes in shell gathering in an early agricultural society at the head of Ise Bay, Japan based on the analysis of almost 20,000 individual shell remains from four coastal settlements. We analyzed historical changes in the composition and size range of the shell species Meretrix lusoria. The most common species went from Crassostrea gigas in the early Middle Yayoi period (about 400–350BC) to M. lusoria in the mid-Middle Yayoi period (about 320–200BC). It is possible that the seacoast tideland, an environment suitable for C. gigas, was buried in sediment from the rivers and thereby transformed into muddy sand bottoms, an environment more suitable for M. lusoria. We also analyzed historical changes in the size range of M. lusoria. The mean size of M. lusoria increased significantly from the early Final Jomon (about 1250–1000BC) to the late Early Yayoi (about 500–400BC), from the late Early Yayoi to the early Middle Yayoi, and from the early to the mid-Middle Yayoi periods. Evidence suggests that during the Yayoi period, the demand for shells decreased and therefore, the pressure to collect M. lusoria also decreased. We concluded that the larger specimens of M. lusoria were collected selectively. more...
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- 2009
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219. Spatial Decomposition Analysis of the Thermodynamics of Cyclodextrin Complexation
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Andriy Kovalenko and Takeshi Yamazaki
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chemistry.chemical_classification ,Molecular dynamics ,Solvation shell ,Cyclodextrin ,chemistry ,Excluded volume ,Solvation ,Thermodynamics ,Molecular orbital theory ,Partial molar property ,Physical and Theoretical Chemistry ,Decomposition analysis ,Computer Science Applications - Abstract
We propose a method of spatial decomposition analysis (SDA) to study the thermodynamics of association in solution, based on three-dimensional molecular theory of solvation. We decompose the solvation thermodynamics quantities into the excluded volume and solvation shell terms and further break them down into partial contributions of the functional groups of the associating species. For illustration, we applied the SDA method to the complexation of β-cyclodextrin and 1-adamantanecarboxylic acid in water. We calculated the changes in the free energy and in the partial molar volume upon the association and decomposed them into the partial contributions of the functional groups to the excluded volume and solvation shell terms. The SDA shows that the adamantyl group of 1-adamantanecarboxylic acid is responsible for the complexation more than its carboxyl group and that the carboxyl has little contribution to the association process. The SDA results are in good agreement with the observation made in a recent molecular dynamics simulation. The SDA method can reveal a microscopic picture for association processes in solution in a number of areas, including protein stability, and might be a useful tool for rational drug design. more...
- Published
- 2009
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220. The uniqueness of pure-strategy Nash equilibrium in rent-seeking games with risk-averse players
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Takeshi Yamazaki
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Economics and Econometrics ,Correlated equilibrium ,Sociology and Political Science ,Symmetric equilibrium ,Rationalizability ,Microeconomics ,symbols.namesake ,Equilibrium selection ,Nash equilibrium ,Best response ,symbols ,Economics ,Epsilon-equilibrium ,Risk dominance ,Mathematical economics - Abstract
This article proves that if each player’s measure of absolute risk aversion is nonincreasing in his/her wealth, then there exists a unique pure-strategy Nash equilibrium in the general rent-seeking game, where risk-averse players can coexist with risk-neutral players, attitude toward risk can differ among players, and concave production functions for lotteries are not necessarily the same among players. more...
- Published
- 2009
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221. Evaluation of Snow Augmentation by Cloud Seeding for Drought Mitigation
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Takeshi Yamazaki, Masataka Murakami, Yoshikazu Kurumizawa, Yuichi Yoshida, Noriyuki Haneda, Akihiro Hashimoto, and Teruyuki Kato
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Water resources ,Atmosphere ,Climatology ,Water storage ,Cloud seeding ,Environmental science ,Climate change ,Snow ,Surface runoff - Abstract
奥利根流域(群馬県北部)は利根川最上流部に位置する多雪地帯であり,融雪を利用したダム運用が春先から初夏にかけての利根川流域への水資源の供給に重要な役割を果たしている.一方,利根川流域は1都5県2900万人の飲み水を支えているが,2~3年に1回程度の割合で渇水が頻発していて,さらに将来の気候変動による降雪量の減少の影響も懸念されている.このような状況の下,冬期間の降雪量を増やし,水資源を安定確保するための人工降雪技術についての基礎的調査が実施されてきた. 本研究では人工降雪技術がどの程度渇水対策に寄与できるのか,数値モデルを用いて検討した.即ち, 2006/2007年冬期間の奥利根流域を対象として,雲解像非静力学大気モデル(NHM)による人工降雪の数値実験結果と積雪融雪モデル・流出モデルを用いて,ダム流入量およびダム貯水量に対する人工降雪の効果を定量的に評価した.この結果,人工降雪を行うことで融雪期(4~6月)の総流入量は矢木沢ダム域で17 %,奈良俣ダム域で20 %増加した.また夏期のダム制限容量に移行する6月30日のダム貯水率で見ると,矢木沢ダムでは70 %から100 %に,奈良俣ダムでは83 %から93 %に増加した.さらに初冬期の貯水率を下げることで渇水を想定した貯水量の計算を行ったところ,人工降雪により渇水を軽減できる可能性が分かった.これらのことから,人工降雪とダム運用を併用することが,今後の気候変動に対して安定的に水資源を確保するための有効な手段の1つであるといえる. more...
- Published
- 2009
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222. A STUDY ON DESIGNED PRESSURES ON LINING OF A SHIELD TUNNEL IN SOFT CLAY BY RIGID PLASTIC FINITE ELEMENT METHOD, CONSIDERING ANISOTROPY OF SOIL
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Takeshi Yamazaki, Shunsuke Kaneko, Takeru Ariizumi, and Osamu Kusakabe
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Soft clay ,business.industry ,Shield ,Geotechnical engineering ,Structural engineering ,business ,Anisotropy ,Geology ,Finite element method - Published
- 2009
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223. 1,1-Diphenyl-2-picrylhydrazyl Radical Scavenging Activity of Binary Mixtures of Antioxidants
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Yuki Honma, Takeshi Yamazaki, Hiromi Miyajima, Kiyoshi Matsumoto, Toshiro Matsui, Makoto Chino, Kazuo Yamagata, Tomoko Shimamura, Ryoichiro Sasa, Hiroshi Matsufuji, and Hiroyuki Ukeda
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Chemistry ,1 1 diphenyl 2 picrylhydrazyl ,Organic chemistry ,Food Science ,Nuclear chemistry - Abstract
DPPHラジカル消去活性測定法を用いて,2成分間の活性に及ぼす効果(相乗効果,相加効果,相殺効果)について検討した.11種の酸化防止剤55通りの組み合わせでは,36通りにおいて統計上相乗効果,1通りで相殺効果と判定される結果が得られた.一方,24種の化合物276通りの組み合わせ(うち15通りは重複)では,74通りにおいて相乗効果,61通りで相殺効果が得られた.しかし,これらの多くの組み合わせによる効果は弱く,相加効果をわずかに上回る,あるいは下回る程度であり,2割以上の活性増強が認められた組み合わせは14通り,2割以下の活性低下が認められた組み合わせは33通りであった.一方,α-トコフェロールとの組み合わせのうち6通りで,p-クマル酸との組み合わせのうち4通りで2割以上の活性増強が観察され,バニリン酸との組み合わせのうち17通りで,p-クマル酸との組み合わせのうち12通りで2割以下の活性低下が観察された. more...
- Published
- 2009
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224. Examination of Original Plant of Jamaica Quassia Extract, a Natural Bittering Agent, Based on Composition of the Constituents
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Takumi Akiyama, Takeshi Yamazaki, Masaharu Asanoma, Ken-ichi Tanamoto, Young Sook Yun, Atsuko Tada, Naoki Sugimoto, and Kyoko Sato
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Surinam quassia ,food.ingredient ,biology ,Traditional medicine ,Plant Extracts ,Chemistry ,Food additive ,General Medicine ,biology.organism_classification ,Mass Spectrometry ,chemistry.chemical_compound ,Quassia ,food ,Neoquassin ,Picrasma ,Quassin ,Quassia amara ,Food Additives ,Composition (visual arts) ,Food science ,Chromatography, Liquid - Abstract
Jamaica quassia extract is a natural bittering agent used as a food additive in Japan. The main constituents of the extract have already been reported to be quassin and neoquassin. In this study, the differences in composition of the constituents among four Jamaican quassia extract products were analyzed by LC/MS. The results showed that the four products have similar compositions of their minor constituents, as well as their main constituents. We isolated four of the minor constituents that were commonly included in the four products, and identified them as 11-dihydro-12-norneoquassin, canthin-6-one, 4-methoxy-1-vinyl-beta-carboline and 4,9-dimethoxy-1-vinyl-beta-carboline. The List of Existing Food Additives in Japan mentions that Jamaica quassia (Picrasma excelsa) is the original plant from which Jamaica quassia extract is produced. However, we presume that Jamaica quassia extract may actually be made from appropriate plants other than Picrasma excelsa, since P. excelsa is listed as an endangered species by the International Union for Conservation of Nature and Natural Resources. We prepared hot water extracts from two other species of plants, Quassia amara (American quassia, Surinam quassia) and P. quassioides ('Nigaki' in Japanese), and investigated their constituents by LC/MS. The results showed that the compositions of the constituents in the Jamaica quassia extract products resembled those in the extract derived from Q. amara. These findings suggest that Jamaica quassia extract products are probably made from Q. amara. more...
- Published
- 2009
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225. Long Term Runoff Analysis of the Lena River Basin using a Distributed Hydrological Model
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Park HoTaek, H. Hayakawa, Takeshi Yamazaki, Takeshi Ohta, Shigemi Hatta, and Kazukiyo Yamamoto
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Hydrology ,geography ,geography.geographical_feature_category ,Hydrology (agriculture) ,Stream flow ,Drainage basin ,Environmental science ,Vegetation ,STREAMS ,Snow ,Surface runoff ,Term (time) - Published
- 2009
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226. Tempo-spatial characteristics of energy budget and evapotranspiration in the eastern Siberia
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Hotaek Park, Kazukiyo Yamamoto, Takeshi Yamazaki, and Takeshi Ohta
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Atmospheric Science ,Global and Planetary Change ,Forestry ,Sensible heat ,Seasonality ,Permafrost ,Atmospheric sciences ,Snow ,Energy budget ,medicine.disease ,Tundra ,Climatology ,Latent heat ,Evapotranspiration ,medicine ,Environmental science ,Agronomy and Crop Science - Abstract
Spatio-temporal variations in the energy budget and evapotranspiration (ET) in eastern Siberia were examined for a period of 19 years, from 1986 to 2004, for the Lena and Kolyma watersheds, which are underlain by permafrost. The energy budget and ET were calculated with a land surface model [Yamazaki, T., Yabuki, H., Ishii, Y., Ohta, T., Ohata, T., 2004. Water and energy exchanges at forests and a grassland in eastern Siberia evaluated using a one-dimensional land surface model. J. Hydrometeol. 5, 504–515] that considered vegetation, snow, and soil processes. Station data were used to compile gridded time series of forcing data. The spatial distribution of the energy budget showed that the latent heat flux (QE) was a significant term in the surface energy budget in forested regions, while the sensible heat (QH) was significant in the tundra region. A similar result was also obtained for the seasonal variation; in the Kolyma watershed, for instance, QH dominated the seasonal energy budget, even during the growing season. In the Lena watershed, 53% of precipitation (PG) was lost through ET, which occurred during a very sharply pronounced growing season. Transpiration (ET) was a major component of ET in the Lena watershed, while in the Kolyma watershed, evaporation from the forest floor (ES) was dominant. This suggested clear relations between the energy budget and the difference in land surface and climate. In the Lena and Kolyma watersheds, a time series of PG exhibited strong annual variations with an increasing trend during 1986–2004. ET also exhibited an increasing trend in the two watersheds. However, the interannual variation was weaker than that of PG, reflecting the influence of extensive permafrost in the area. The ET components also showed an increasing trend. In contrast, ES decreased during 1986–2004, the trend of ES thus being inversely correlated to that of PG. Interestingly, annual ET also exhibited an inverse correlation with PG in the Lena and Kolyma watersheds, although this relationship was weak. In contrast, ET displayed a strong correlation with air temperature (Ta) and the timing of the disappearance of snow. more...
- Published
- 2008
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227. Food Habits of Finless Porpoises Neophocaena phocaenoides in Western Kyushu, Japan
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Miki Shirakihara, Kenji Seki, Akira Takemura, Takeshi Yamazaki, Kunio Shirakihara, and Hideyoshi Yoshida
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geography ,Ecology ,biology ,geography.lake ,Sepiidae ,Sciaenidae ,biology.organism_classification ,Finless porpoise ,Gizzard shad ,Fishery ,Konosirus punctatus ,Clupeidae ,Octopodidae ,Genetics ,Animal Science and Zoology ,Bay ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation - Abstract
We examined the stomach contents of 87 finless porpoises (Neophocaena phocaenoides) in the Ariake Sound‐ Tachibana Bay area and Omura Bay in western Kyushu, Japan, between 1987 and 1992. Fish (Gobiidae and Atherinidae) were the most numerous and most frequently occurring prey in Omura Bay, whereas both cephalopods (Octopodidae, Sepiidae, Sepiolidae/Sepiidae, and Loliginidae) and fishes (Clupeidae, Engraulidae, and Sciaenidae) were equally important in Ariake Sound‐Tachibana Bay. Species compositions in the commercial catch differed between the 2 waters, suggesting that differences in prey availability may explain the geographical variation in diet. Finless porpoises in Ariake Sound‐Tachibana Bay showed ontogenetic and seasonal variations in diet. The mean length at weaning was estimated to be 101 cm, corresponding to approximately 6 months of age. Calves fed on small-sized demersal fish and cephalopods. The predominant prey species for sexually mature individuals (including lactating females) consisted of konoshiro gizzard shad (Konosirus punctatus) and cephalopods. Seasonal availability of these organisms may be related to births in the fall‐winter season in Ariake Sound‐Tachibana Bay. Size-dependent prey selectivity was equivocal. Day‐night difference in foraging time was not indicated by the index of stomach fullness. more...
- Published
- 2008
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228. Hypoxia induces expression of a GPI-anchorless splice variant of the prion protein
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Tomoshi Kakeya, Ayako Sakai, Ken-ichi Tanamoto, Jun-ichi Sawada, Yutaka Kikuchi, Kosuke Takatori, Takeshi Yamazaki, Osamu Nakajima, Naoto Yamaguchi, Haruo Matsuda, and Kikuko Ikeda
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Signal peptide ,chemistry.chemical_classification ,Messenger RNA ,Alternative splicing ,Cell Biology ,Biology ,Biochemistry ,Molecular biology ,nervous system diseases ,Oxygen tension ,Amino acid ,PRNP ,Open reading frame ,chemistry ,lipids (amino acids, peptides, and proteins) ,Glycoprotein ,Molecular Biology - Abstract
The human prion protein (PrP) is a glycoprotein with a glycosylphosphatidylinositol (GPI) anchor at its C-terminus. Here we report alternative splicing within exon 2 of the PrP gene (PRNP) in the human glioblastoma cell line T98G. The open reading frame of the alternatively spliced mRNA lacked the GPI anchor signal sequence and encoded a 230 amino acid polypeptide. Its product, GPI-anchorless PrP (GPI− PrPSV), was unglycosylated and soluble in non-ionic detergent, and was found in the cytosolic fraction. We also detected low levels of alternatively spliced mRNA in human brain and non-neuronal tissues. When long-term passaged T98G cells were placed in a low-oxygen environment, alternatively spliced mRNA expression increased and expression of normally spliced PrP mRNA decreased. These findings imply that oxygen tension regulates GPI− PrPSV expression in T98G cells. more...
- Published
- 2008
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229. Global stability of unique Nash equilibrium in Cournot oligopoly and rent-seeking game
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Takeshi Yamazaki and Koji Okuguchi
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Computer Science::Computer Science and Game Theory ,Economics and Econometrics ,Control and Optimization ,Applied Mathematics ,Symmetric equilibrium ,Trembling hand perfect equilibrium ,Microeconomics ,symbols.namesake ,Nonlinear Sciences::Adaptation and Self-Organizing Systems ,Subgame ,Equilibrium selection ,Nash equilibrium ,Best response ,Economics ,symbols ,Folk theorem ,Epsilon-equilibrium ,Mathematical economics - Abstract
A sufficient condition is derived for the global stability of a unique interior Nash equilibrium in an aggregative game. The condition is applied to investigate the global stability of the Nash–Cournot equilibrium in Cournot oligopoly without product differentiation and that of the Nash equilibrium in rent-seeking games. more...
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- 2008
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230. Dual-Doppler lidar observation of horizontal convective rolls and near-surface streaks
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Izumi Yamada, Yasuhiro Murayama, Nobumitsu Tsunematsu, Sha Weiming, Toshikazu Itabe, Shoken Ishii, Takeshi Yamazaki, Hironori Iwai, Kohei Mizutani, Dai Matsushima, Naoki Matayoshi, and Toshiki Iwasaki more...
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Convection ,Meteorology ,Planetary boundary layer ,Doppler radar ,law.invention ,symbols.namesake ,Geophysics ,Lidar ,law ,Sea breeze ,symbols ,General Earth and Planetary Sciences ,Aerodrome ,Doppler effect ,Geology ,Large eddy simulation - Abstract
Received 4 May 2008; revised 9 June 2008; accepted 18 June 2008; published 23 July 2008. [1] Dual-Doppler lidar and heliborne sensors were used to investigate the three-dimensional (3D) structure of the wind field over Sendai Airport in June 2007. The 3D structures of several-hundred-meter-scale horizontal convective rolls (HCRs) in the sea-breeze layer were observed by the dual-Doppler lidar. The scale of the HCRs determined by the heliborne sensors roughly agreed with that determined by the dual-Doppler lidar. Analysis of the dual-Doppler lidar data showed that the region of upward flow in the HCRs originated in near-surface low-speed streaks. This structure is consistent with the results of large-eddy simulations of the atmospheric boundary layer. The aspect ratios of the HCRs were close to those predicted by linear theories. Citation: Iwai, H., et al. (2008), Dual-Doppler lidar observation of horizontal convective rolls and near-surface streaks, Geophys. Res. Lett., 35, L14808, doi:10.1029/ 2008GL034571. more...
- Published
- 2008
231. Survey of Synthetic Disinfectants in Grapefruit Seed Extract and Its Compounded Products
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Ken-ichi Tanamoto, Naoki Sugimoto, Kyoko Sato, Atsuko Tada, Yuko Yoneda, Akira Kunugi, Young Sook Yun, Takeshi Yamazaki, and Masanori Kuroyanagi
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Benzethonium ,food.ingredient ,Plant Extracts ,Chemistry ,Food additive ,Disinfectant ,medicine.medical_treatment ,Ms analysis ,General Medicine ,Grapefruit seed extract ,Mass Spectrometry ,food ,Citrus paradisi ,Natural food ,Seeds ,Deodorant ,medicine ,Food Additives ,Chromatography, Thin Layer ,Food science ,Benzalkonium Compounds ,Disinfectants - Abstract
Grapefruit seed extract (GSE), derived from the seeds of grapefruit (Citrus paradisi MCAF.), is listed as a natural food additive in Japan. Products containing GSE are used as disinfectants made from only natural sources, especially after Japanese researchers found that GSE prevents the growth of norovirus. On the other hand, recent overseas studies indicated that synthetic disinfectants, such as benzalkonium and benzethonium chlorides, were present in some commercial GSE products. To confirm the quality of commercial GSE products available in Japanese markets, we carried out comprehensive research to identify the major constituents of commercial GSE products which are used as food additives (13 products from 6 manufacturers), dietary supplements (5 products from 4 manufacturers), cosmetic materials (16 products from 10 manufacturers) and disinfectant or deodorant sprays (7 products from 7 manufacturers). By means of NMR and LC/MS analysis, synthetic disinfectants such as benzethonium or benzalkonium salts were detected in most of the commercial GSE products. more...
- Published
- 2008
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232. Chromatographic Evaluation and Characterization of Components of Gentian Root Extract Used as Food Additives
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Atsuko Tada, Morio Yoshimura, Yusai Ito, Sara Morimoto, Hiroshi Akiyama, Naoki Sugimoto, Takashi Yoshida, Yoshiaki Amakura, and Takeshi Yamazaki
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food.ingredient ,Iridoid ,medicine.drug_class ,Isovitexin ,Iridoid Glucosides ,01 natural sciences ,High-performance liquid chromatography ,Plant Roots ,chemistry.chemical_compound ,food ,Loganic acid ,Drug Discovery ,Vanillic acid ,medicine ,Iridoids ,Gentiana ,Chromatography, High Pressure Liquid ,Chromatography ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Plant Extracts ,Food additive ,010401 analytical chemistry ,Chemical data ,General Chemistry ,General Medicine ,Amarogentin ,0104 chemical sciences ,Food Additives - Abstract
Gentian root extract is used as a bitter food additive in Japan. We investigated the constituents of this extract to acquire the chemical data needed for standardized specifications. Fourteen known compounds were isolated in addition to a mixture of gentisin and isogentisin: anofinic acid, 2-methoxyanofinic acid, furan-2-carboxylic acid, 5-hydroxymethyl-2-furfural, 2,3-dihydroxybenzoic acid, isovitexin, gentiopicroside, loganic acid, sweroside, vanillic acid, gentisin 7-O-primeveroside, isogentisin 3-O-primeveroside, 6'-O-glucosylgentiopicroside, and swertiajaposide D. Moreover, a new compound, loganic acid 7-(2'-hydroxy-3'-O-β-D-glucopyranosyl)benzoate (1), was also isolated. HPLC was used to analyze gentiopicroside and amarogentin, defined as the main constituents of gentian root extract in the List of Existing Food Additives in Japan. more...
- Published
- 2016
233. Contents Vol. 134, 2016
- Author
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Michiko Shimada, A. Ahsan Ejaz, Martin H. de Borst, Girish Singhania, Marc G. Vervloet, Fellype C. Barreto, Kawther F. Alquadan, José Andrade Moura Junior, Takeshi Yamazaki, Ju Hyung Kang, Richard J. Johnson, Yasuyuki Sato, Xiang Liu, Asako Hayashi, Yang Yang, Haing Woon Baik, Hee Gyung Kang, Chen Yu, Constança Margarida Sampaio Cruz, Seung-Min Yoo, Il-Soo Ha, Abhilash Koratala, Joo-Heon Kim, Marlene Antonia dos Reis, Aaltje Y. Adema, Takayuki Okamoto, Hongqi Ren, Xiangyang Li, Deshu Dai, Yun Liu, Hae Il Cheong, Renxian Tang, Cassiano Augusto Braga Silva, Tadashi Ariga, Maarten A. de Jong, Chung Gyu Park, Chao Yan, Pieter M. ter Wee, Satoshi Sasaki, Jiadai Xu, and Druckerei Stückle more...
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Traditional medicine ,business.industry ,Medicine ,business - Published
- 2016
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234. Heterogeneity and Number of Players in Rent-Seeking, Innovation, and Patent-Race Games
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Noriaki Matsushima and Takeshi Yamazaki
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TheoryofComputation_MISCELLANEOUS ,Marginal cost ,media_common.quotation_subject ,05 social sciences ,ComputingMilieux_PERSONALCOMPUTING ,Cournot competition ,Microeconomics ,Race (biology) ,0502 economics and business ,Value (economics) ,Economics ,050207 economics ,Set (psychology) ,Rent-seeking ,050205 econometrics ,media_common - Abstract
Many economists have studied rent-seeking contests, innovation tournaments, and patent-race games independently. These three seemingly different games are known to be strategically equivalent under some reasonable assumptions. In these classic games, it is assumed that the value of a prize, i.e. the gain from rent-seeking, achieving an innovation, or obtaining a patent, is exogenously given and does not depend on the number of players, so that an increase in the number of players decreases the winning rate of each player. However, if players engage in R&D and then set quantities a la Cournot, the value of the prize in general depends on the number of players. In this paper, we set up a model with one efficient player and identical inefficient players to analyze how an increase in heterogeneity among players or the number of players changes the wining rate of the efficient player. One of the main results is that if the number of players is larger than some critical value, which can be less than two, an increase in the number of inefficient players always increases the winning rate of the efficient player. more...
- Published
- 2016
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235. On the Nash Equilibrium of Asymmetric Public-Good Contests
- Author
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Takeshi Yamazaki
- Subjects
symbols.namesake ,Subgame ,Nash equilibrium ,Best response ,Symmetric equilibrium ,Trembling hand perfect equilibrium ,Economics ,symbols ,Risk dominance ,Epsilon-equilibrium ,CONTEST ,Mathematical economics - Abstract
In this paper we study a rent-seeking contest where several groups compete for a prize which is a public good among players in a group. In the contest players in a group may evaluate the prize of the contest differently. We prove that such an asymmetric public-good contest with a general contest success function possesses a unique pure-strategy Nash equilibrium, where the equilibrium is unique in the sense that the total expenditure of each group is uniquely determined. We also present some comparative statics in the model. more...
- Published
- 2016
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236. On the Works of Professor Koji Okuguchi
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Takeshi Yamazaki
- Subjects
media_common.quotation_subject ,Intergenerational equity ,Art history ,Performance art ,Art ,Cournot competition ,Positive economics ,media_common - Abstract
This chapter briefly explains life and works of Professor Koji Okuguchi. This chapter also contains a list of his selected publications.
- Published
- 2016
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237. Quantitative nuclear magnetic resonance spectroscopic determination of the oxyethylene group content of polysorbates
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Chikako Yomota, Noriko Furusho, Ken-ichi Tanamoto, Naoki Sugimoto, Takeshi Yamazaki, Kyoko Sato, Ryo Koike, and Makoto Tanno
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Ethylene Oxide ,Polysorbate ,Magnetic Resonance Spectroscopy ,food.ingredient ,Health, Toxicology and Mutagenesis ,Potassium hydrogen phthalate ,Food additive ,Public Health, Environmental and Occupational Health ,Analytical chemistry ,Polysorbates ,Sorbitan monolaurate ,General Chemistry ,Nuclear magnetic resonance spectroscopy ,Toxicology ,Surface-Active Agents ,chemistry.chemical_compound ,food ,Nuclear magnetic resonance ,chemistry ,Chemistry (miscellaneous) ,Food Additives ,Titration ,Ethylene glycol ,Food Science - Abstract
Guidelines for the oxyethylene group (EO) content of polysorbates are set by the Food and Agriculture Organization/World Health Organization Joint Expert Committee on Food Additives. However, the classical titration method for EO determination is difficult and time-consuming. Here, we show that quantitative (1)H-nuclear magnetic resonance spectroscopy can determine the EO contents of polysorbates rapidly and simply. The EO signals were identified through comparisons with sorbitan monolaurate and poly(ethylene glycol) distearate. Potassium hydrogen phthalate was used as an internal standard. The EO contents were estimated from the ratio of the signal intensities of EO to the internal standard. Two nuclear magnetic resonance systems were used to validate the proposed method. The EO content of commercial polysorbates 20, 60, 65, and 80 was determined to be within the recommended limits using this technique. Our approach thus represents an additional or alternative method of determining the EO contents of polysorbates. more...
- Published
- 2007
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238. Molecular Basis for Water-Promoted Supramolecular Chirality Inversion in Helical Rosette Nanotubes
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Hicham Fenniri, Takeshi Yamazaki, Ross S. Johnson, and Andriy Kovalenko
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Models, Molecular ,Circular dichroism ,Supramolecular chirality ,Guanine ,Stereochemistry ,Molecular Conformation ,Supramolecular chemistry ,Microscopy, Atomic Force ,Biochemistry ,Catalysis ,Cytosine ,Colloid and Surface Chemistry ,Microscopy, Electron, Transmission ,Nucleic Acids ,Molecule ,Conformational isomerism ,Nanotubes ,Chemistry ,Hydrogen bond ,Circular Dichroism ,Methanol ,Water ,General Chemistry ,Kinetics ,Crystallography ,Helix ,Microscopy, Electron, Scanning ,Thermodynamics ,Chirality (chemistry) - Abstract
Helical rosette nanotubes (RNTs) are obtained through the self-assembly of the GwedgeC motif, a self-complementary DNA base analogue featuring the complementary hydrogen bonding arrays of both guanine and cytosine. The first step of this process is the formation of a 6-membered supermacrocycle (rosette) maintained by 18 hydrogen bonds, which then self-organizes into a helical stack defining a supramolecular sextuple helix whose chirality and three-dimensional organization arise from the chirality, chemical structure, and conformational organization of the GwedgeC motif. Because a chiral GwedgeC motif is predisposed to express itself asymmetrically upon self-assembly, there is a natural tendency for it to form one chiral RNT over its mirror image. Here we describe the synthesis and characterization of a chiral GwedgeC motif that self-assembles into helical RNTs in methanol, but undergoes mirror image supramolecular chirality inversion upon the addition of very small amounts of water ( more...
- Published
- 2007
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239. Allosteric inhibition of rat neuronal nitric-oxide synthase caused by interference with the binding of calmodulin to the enzyme
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Takeshi Yamazaki, Shiro Kominami, Shunsuke Izumi, Shigeyuki Kitamura, Shigeru Ohta, and Koji Ohashi
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DNA, Complementary ,Calmodulin ,Arginine ,Allosteric regulation ,Biophysics ,Wasp Venoms ,Nitric Oxide Synthase Type I ,Biochemistry ,Melittin ,chemistry.chemical_compound ,Allosteric Regulation ,Animals ,Enzyme Inhibitors ,Binding site ,Molecular Biology ,Cytochrome Reductases ,chemistry.chemical_classification ,Binding Sites ,ATP synthase ,biology ,Chemistry ,Melitten ,Recombinant Proteins ,Rats ,Kinetics ,Enzyme ,nervous system ,Mastoparan ,biology.protein ,Citrulline ,Intercellular Signaling Peptides and Proteins ,Peptides - Abstract
A sigmoid-type dependence on the inhibitor concentration was observed in the cytochrome c reductase activity for peptide inhibitors (mastoparan and melittin), calmodulin antagonists (W-7 and tamoxifen) and monobutyltin in a reconstituted system comprised of recombinant rat neuronal nitric-oxide synthase (nNOS) and calmodulin (CaM). The increase in the concentration of CaM in the system induced a decrease in the inhibitory effect, indicating that the inhibitors might interfere with the interaction between nNOS and CaM. The changes in the fluorescence spectra of dansylated CaM caused by the addition of mastoparan, melittin and monobutyltin indicated complex formation between CaM and those compounds, which led to the decrease in the effective concentration of CaM available to nNOS. The sigmoid-type inhibition of mastoparan and melittin fit the theoretical equations quite well, assuming that two CaM molecules bind cooperatively to one nNOS homodimer. Monobutyltin, tamoxifen and W-7 were found to inhibit nNOS activity by binding to the CaM binding site of the nNOS homodimer, in addition to the binding of the inhibitors to calmodulin. These compounds inhibited the l -citrulline formation of nNOS from l -arginine, and the inhibitory effects were abrogated by raising the concentration of calmodulin. It became clear that the binding of calmodulin to nNOS can be interfered with in two ways: (1) via a decrease in the effective concentration of calmodulin caused by complex formation between the inhibitor and calmodulin, and (2) via the inhibition of the binding of calmodulin to nNOS caused by the occupation of the binding site by the inhibitor. more...
- Published
- 2007
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240. Authentication and Chemical Study of Isodonis Herba and Isodonis Extracts
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Takeshi Kawasaki, Masao Fujita, Atsuko Tada, Hiroyuki Kamakura, Yukihiro Goda, Hiroshi Shimada, Masanori Kuroyanagi, Ik Hwi Kim, Yutaka Yamamoto, Takuro Maruyama, Naoki Sugimoto, and Takeshi Yamazaki
- Subjects
food.ingredient ,Crude drug ,Mass Spectrometry ,food ,Liquid chromatography–mass spectrometry ,DNA, Ribosomal Spacer ,Drug Discovery ,Internal transcribed spacer ,Ribosomal DNA ,Plants, Medicinal ,Chromatography ,Molecular Structure ,Traditional medicine ,Chemotype ,Plant Extracts ,Chemistry ,Food additive ,General Chemistry ,General Medicine ,Phenotype ,DNA profiling ,Herb ,Isodon ,Food Additives ,Diterpenes ,Diterpenes, Kaurane ,Chromatography, Liquid - Abstract
Isodonis Herba is used as a Japanese dietary supplement and folk medicine. The extract of the herb (Isodonis extract) is also used as a food additive whose major compound is enmein (1). Here we compared internal transcribed spacer sequences of nuclear ribosomal DNA from Isodonis Herba available on the Japanese and Chinese crude drug markets, and found that the former derived from Isodon japonicus and Isodon trichocarpus, while the latter derived from distinct species such as Isodon eriocalyx. The liquid chromatography/mass spectrometry profiles of Isodonis Herba were classified into four chemotypes (A to D) according to the ratio of the major constituents. Types B and C contained 1 and oridonin (2) as major components, respectively. An intermediate (or mixed) form of types B and C in various ratios was designed type A. Type D contained eriocalyxin B (3) as its major component. Japanese herba were types A-C, while Chinese herba were types C and D. The commercial Isodonis extract products tested were classified as type D, suggesting that they originated from Chinese Herba. Understanding the relationship between extract constituents and DNA profiles is important for the official specification of dietary supplements and food additives of plant origin. more...
- Published
- 2007
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241. Flux variation in a Siberian taiga forest near Yakutsk estimated by a one-dimensional model with routine data, 1986–2000
- Author
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Rikie Suzuki, Tetsuo Ohata, Takeshi Ohta, and Takeshi Yamazaki
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Climatology ,Latent heat ,Evapotranspiration ,Taiga ,Potential evaporation ,Environmental science ,Vegetation ,Precipitation ,Sensible heat ,Normalized Difference Vegetation Index ,Water Science and Technology - Abstract
For a larch forest site near Yakutsk, energy and water fluxes are estimated and their variations are investigated using a one-dimensional land surface model with daily routine data. The estimation period is 1986-2000, including the period before the start of tower observation (1997) on the left bank of the Lena River. The land surface model includes three submodels: vegetation, snow cover, and soil. The model can calculate water and energy fluxes above and within the forest if meteorological data over the forest are given as input. Data used in this study are Baseline Meteorological Data in Siberia (BMDS) Version 3. This set comprises daily data of main meteorological elements. The procedure is as follows: (1) preparation of equations between routine Yakutsk data and larch tower data; (2) estimation of past meteorological data over the taiga using those equations; and (3) estimation of fluxes using the one-dimensional model. The date of leaf-out start is parameterized with soil temperature and accumulated air temperature. It corresponds to the green-up time obtained from satellite normalized difference vegetation index (NDVI) data. Estimated monthly deviation of net radiation, R n , is 10 Wm -2 . Its maximum is 20 Wm -2 . The monthly deviation of latent heat flux, LE, is less than 12 Wm -2 . Its warm season average is less than 7 Wm -2 . Although the magnitude of LE is almost zero in December and January, and several Wm -2 aside from these 2 months, the sensible heat flux, H, sometimes becomes negative during the cold season. The variation of evapotranspiration is considerably smaller than that of precipitation. The evapotranspiration (E) normalized by potential evaporation (Ep), E/Ep is 0.37-0.44 in the warm season; it tends to be large when leaf-out starts early. The amount of evapotranspiration in the warm season can be estimated. more...
- Published
- 2007
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242. Neocrocin A: a Novel Crocetin Glycoside with a Unique System for Binding Sugars Isolated from Gardenia Yellow
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Ken-ichi Tanamoto, Takeshi Yamazaki, Young Sook Yun, Kyoko Sato, Yoshinori Uekusa, Naoki Sugimoto, and Akira Kunugi
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Magnetic Resonance Spectroscopy ,Anomer ,Stereochemistry ,Crocetin ,Carbohydrates ,Gardenia jasminoides ,Antioxidants ,Crocin ,chemistry.chemical_compound ,Drug Discovery ,Anticarcinogenic Agents ,Glycosyl ,Glycosides ,Binding site ,Vitamin A ,chemistry.chemical_classification ,Binding Sites ,Molecular Structure ,biology ,Plant Extracts ,Glycoside ,Stereoisomerism ,General Chemistry ,General Medicine ,Gardenia ,biology.organism_classification ,Carotenoids ,chemistry - Abstract
A novel crocetin glycosyl ester, neocrocin A (2), was isolated from gardenia yellow. The structure of 2 was elucidated as that of an all-trans-crocetin beta-D-gentiobiosyl beta-D-glucopyranosyl-(1--6)-D-2-deoxy-glucopyranos-2-yl diester based on chemical and spectral data. The findings provide evidence that the binding system of crocetin glycosides is not limited to the anomeric position. more...
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- 2007
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243. Comparison of Conventional Antioxidants Assays for Evaluating Potencies of Natural Antioxidants as Food Additives by Collaborative Study
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Hiroshi Matsufuji, Hiroyuki Ukeda, Toshiro Matsui, Takashi Tokuda, Ritaro Matsuura, Tomoko Shimamura, Kiyoshi Matsumoto, Takeshi Yamazaki, and Naoki Sugimoto
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food.ingredient ,food ,Chemistry ,Food additive ,Food science ,Food Science - Abstract
既存添加物のうち,酸化防止剤に分類される品目の抗酸化活性に基づく新たな品質規格策定を最終目的とし,その基礎となる抗酸化活性評価法の公定化に対する適用性の検討を行った.本研究では,代表的な分光学的抗酸化活性測定法であるDPPH法,ABTS法,WST-1法による単一化合物酸化防止剤(9種類)の抗酸化活性測定を3カ所の研究室で共同試験し,得られた結果の室間再現精度の検証を行った.その結果,DPPH法,ならびにABTS法は単一化合物酸化防止剤の抗酸化活性測定において,比較的高い測定精度を示すことが判明した.その一方で,WST-1法は先の2法と比較すると測定精度に劣るという結果が得られた.DPPH法,ならびにABTS法は更に研究室数を増やして試験室間共同試験を行い,分析法の妥当性確認を行うことにより,公定法化を進めることが可能であると考えられた. more...
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- 2007
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244. 2+1 flavor QCD simulation on a $96^4$ lattice
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K. I. Ishikawa, Takeshi Yamazaki, Y. Kuramashi, Naoya Ukita, Yoshifumi Nakamura, Yusuke Namekawa, T. Yoshié, N. Ishizuka, and Y. Taniguchi
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Quantum chromodynamics ,Quark ,Physics ,Particle physics ,Chiral perturbation theory ,High Energy Physics::Lattice ,Hadron ,High Energy Physics - Lattice (hep-lat) ,High Energy Physics::Phenomenology ,FOS: Physical sciences ,Pseudoscalar meson ,Renormalization ,High Energy Physics - Lattice ,Hadron spectroscopy ,High Energy Physics::Experiment ,Nucleon - Abstract
We generate $2+1$ flavor QCD configurations near the physical point on a $96^4$ lattice employing the 6-APE stout smeared Wilson clover action with a nonperturbative $c_{\rm SW}$ and the Iwasaki gauge action at $\beta=1.82$. The physical point is estimated based on the chiral perturbation theory using several data points generated by the reweighting technique from the simulation point, wherer $m_\pi$,$m_K$ and $m_\Omega$ are used as physical inputs. The physics results include the quark masses, the hadron spectrum, the pseudoscalar meson decay constants and nucleon sigma terms, using the nonperturbative renormalization factors evaluated with the Schrodinger functional method., Comment: 7 pages, 10 figures. Proceedings of the 33rd International Symposium on Lattice Field Theory, July 14-18, 2015, Kobe, Japan more...
- Published
- 2015
245. [Determination of the Plant Origin of Licorice Oil Extract, a Natural Food Additive, by Principal Component Analysis Based on Chemical Components]
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Takako Suematsu, Kayo Yoshimatsu, Takashi Ohtsuki, Hiroshi Akiyama, Yukiyoshi Tamura, Toshio Fukai, Nobuo Kawahara, Takeshi Yamazaki, Maiko Tahara, Kazunori Arifuku, Naoki Sugimoto, Atsuko Tada, and Kyoko Ishizuki more...
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food.ingredient ,Antioxidant ,Magnetic Resonance Spectroscopy ,Licochalcone A ,medicine.medical_treatment ,Plant Roots ,Mass Spectrometry ,chemistry.chemical_compound ,food ,Chalcones ,Phenols ,medicine ,Glycyrrhiza ,Plant Oils ,Food science ,biology ,Ethanol ,Plant Extracts ,Food additive ,Glycyrrhiza uralensis ,General Medicine ,biology.organism_classification ,Isoflavones ,Rhizome ,chemistry ,Principal component analysis ,Food Additives ,Protons ,Glabridin ,Chromatography, Liquid - Abstract
"Licorice oil extract" (LOE) (antioxidant agent) is described in the notice of Japanese food additive regulations as a material obtained from the roots and/or rhizomes of Glycyrrhiza uralensis, G. inflata or G. glabra. In this study, we aimed to identify the original Glycyrrhiza species of eight food additive products using LC/MS. Glabridin, a characteristic compound in G. glabra, was specifically detected in seven products, and licochalcone A, a characteristic compound in G. inflata, was detected in one product. In addition, Principal Component Analysis (PCA) (a kind of multivariate analysis) using the data of LC/MS or (1)H-NMR analysis was performed. The data of thirty-one samples, including LOE products used as food additives, ethanol extracts of various Glycyrrhiza species and commercially available Glycyrrhiza species-derived products were assessed. Based on the PCA results, the majority of LOE products was confirmed to be derived from G. glabra. This study suggests that PCA using (1)H-NMR analysis data is a simple and useful method to identify the plant species of origin of natural food additive products. more...
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- 2015
246. Effects of heat stress on production, somatic cell score and conception rate in Holsteins
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Koichi, Hagiya, Kiyoshi, Hayasaka, Takeshi, Yamazaki, Tatsuo, Shirai, Takefumi, Osawa, Yoshinori, Terawaki, Yoshitaka, Nagamine, Yutaka, Masuda, and Mitsuyoshi, Suzuki
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Hot Temperature ,Temperature ,Humidity ,Milk Proteins ,Insemination ,Fats ,Milk ,Quantitative Trait, Heritable ,Fertilization ,Animals ,Lactation ,Cattle ,Female ,Seasons ,Heat-Shock Response - Abstract
We examined the effects of heat stress (HS) on production traits, somatic cell score (SCS) and conception rate at first insemination (CR) in Holsteins in Japan. We used a total of 228 242 records of milk, fat and protein yields, and SCS for the first three lactations, as well as of CR in heifers and in first- and second-lactation cows that had calved for the first time between 2000 and 2012. Records from 47 prefectural weather stations throughout Japan were used to calculate the temperature-humidity index (THI); areas were categorized into three regional groups: no HS (THI 72), mild HS (72 ≤ THI 79), and moderate HS (THI ≥ 79). Trait records from the three HS-region groups were treated as three different traits and trivariate animal models were used. The genetic correlations between milk yields from different HS groups were very high (0.91 to 0.99). Summer calving caused the greatest increase in SCS, and in the first and second lactations this increase became greater as THI increased. In cows, CR was affected by the interaction between HS group and insemination month: with summer and early autumn insemination, there was a reduction in CR, and it was much larger in the mild- and moderate-HS groups than in the no-HS group. more...
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- 2015
247. Lattice Studies on 8-Flavor QCD in The Light of Physics Beyond The Standard Model
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Toshihide Maskawa, Ed Bennett, Koichi Yamawaki, Masafumi Kurachi, Hiroshi Ohki, Yasumichi Aoki, Takeshi Yamazaki, Kei-ichi Nagai, Akihiro Shibata, Tatsumi Aoyama, Kohtaroh Miura, Enrico Rinaldi, Kobayashi-Maskawa Institute, Nagoya University, Department of Physics [Swansea], College of Science [Swansea], Swansea University-Swansea University, KEK (High energy accelerator research organization), Centre de Physique Théorique - UMR 7332 (CPT), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), CPT - E1 Physique des particules, Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), RIKEN BNL Research Center (RBRC), Brookhaven National Laboratory [Upton, NY] (BNL), UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE)-UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE), Lawrence Livermore National Laboratory (LLNL), Graduate School of Pure and Applied Sciences, Tsukuba, U.S. Department of Energy [Washington] (DOE)-UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), and State University of New York (SUNY)-State University of New York (SUNY) more...
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Quantum chromodynamics ,Physics ,Nuclear and High Energy Physics ,Particle physics ,010308 nuclear & particles physics ,[PHYS.HLAT]Physics [physics]/High Energy Physics - Lattice [hep-lat] ,High Energy Physics::Lattice ,Physics beyond the Standard Model ,High Energy Physics::Phenomenology ,Lattice field theory ,Technicolor ,Lattice QCD ,01 natural sciences ,Lattice gauge theory ,[PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph] ,0103 physical sciences ,Higgs boson ,High Energy Physics::Experiment ,010306 general physics ,ComputingMilieux_MISCELLANEOUS ,Boson - Abstract
We report the latest results of the LatKMI collaboration on 8-flavor QCD using Monte Carlo simulations of the lattice gauge theory. The subject receives growing interest with regards to physics beyond the Standard Model (BSM). We show that a flavor-singlet scalar meson (σ) emerges as one of the lightest bound states and can be a composite Higgs boson with mass 125 GeV. The light σ may be a technidilaton, a pseudo Nambu-Goldstone boson of the approximate scale symmetry, which results from a slowly running (walking) coupling constant associated with an infra-red fixed point. Consistently to this reasoning, a mass anomalous dimension γ is found to be large γ ∼ 1 . We discuss the applicability of 8-flavor QCD to the BSM model building. more...
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- 2015
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248. Lattice study of flavor-singlet scalar in large Nf QCD
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Takeshi Yamazaki
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Quantum chromodynamics ,Physics ,Particle physics ,Scalar field theory ,Lattice (order) ,Singlet state ,Scalar field ,Flavor - Published
- 2015
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249. Hadronic Interaction
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Takeshi Yamazaki
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- 2015
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250. Conformality in twelve-flavor QCD
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Masafumi Kurachi, Ed Bennett, Takeshi Yamazaki, Akihiro Shibata, Tatsumi Aoyama, Enrico Rinaldi, Kei-ichi Nagai, Toshihide Maskawa, Kohtaroh Miura, Koichi Yamawaki, Hiroshi Ohki, and Yasumichi Aoki
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Physics ,Quantum chromodynamics ,Particle physics ,Flavor - Published
- 2015
- Full Text
- View/download PDF
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