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Simultaneous Determination of Catechins and Caffeine in Green Tea-Based Beverages and Foods for Specified Health Uses

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Food and Nutrition Sciences 2017年第3期8卷 316-325页

作者： keiji maruyama Fumiko Kihara-Negishi Naoki Ohkura Yasuhiro Nakamura Miwako Nasui Moemi Saito Research Center for Practical Training of Student Pharmacists School of Pharma-Sciences Teikyo University Tokyo Japan Department of Life and Health Sciences School of Pharma-Sciences Teikyo University Tokyo Japan Department of Medical and Pharmaceutical Sciences School of Pharma-Sciences Teikyo University Tokyo Japan

Catechins in green tea have various useful features including antioxidant activity and preventive effects on metabolic syndrome. Various beverages that are enriched with tea catechins are marketed as Foods for Specified Health Uses (FOSHU) in Japan. However, recent reports have indicated that excessive consumption of green tea extracts as a dietary supplement are associated with adverse health effects such as liver disorders. Various catechins and caffeine are constituents of FOSHU tea-based beverages. The amount of catechins in FOSHU products is displayed on labels as total catechin content, but the content of individual catechins are not provided. Although health hazards of FOSHU products have rarely been reported, precise information about the content and types of catechins in FOSHU products is needed to ensure safety. We used high-performance liquid chromatography with a photodiode array (HPLC/PDA) to simultaneously identify and quantify catechins and caffeine in green tea-based popular beverages and FOSHU beverages. This technique allowed simultaneous quantitation of five types of catechins and caffeine in green tea without complicated sample preparation. Epigallocatechin gallate (EGCG) and epigallocatechin EGC were the main catechins in various FOSHU beverages and the concentrations of almost all catechins were higher in FOSHU, than in popular green tea-based beverages. The concentrations of EGCG in green tea-based popular beverages and in FOSHU beverages were 5.4 - 7.3 and 10.2 - 41.9 mg/100mL, respectively, with the highest concentration being in a product named Healthya (approximately 147 mg/bottle). The simultaneous determination of compounds such as catechins and caffeine in FOSHU beverages can help to estimate beneficial and adverse effects to prevent deleterious effects on health and the excessive consumption of FOSHU beverages containing high concentrations of tea catechins should be avoided.

关键词： Simultaneous Quantitation High-Performance Liquid Chromatography-Photodiode Catechin Caffeine Health Food Dietary Supplement

Estimation of Unit Flood Discharge for Various Land Use Types with a Focus on Urbanization

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Open Journal of Modern Hydrology 2016年第4期6卷 195-211页

作者： Manabu Segawa Toshisuke maruyama keiji Takase Faculty of Environmental Science Ishikawa Prefectural University Ishikawa Japan

We proposed unit flood discharge model that defined as the discharge into end-order (smallest) drainage canals. The discharge acts an important role for estimating regional flooding by big rainfall events which leading roughly estimation of flood discharge associated with land use changes as urbanization. In some areas of Japan, increased urbanization with insufficient drainage canal capacity has led to increasingly frequent flooding and flood damage. The aim of this study was to investigate the effect of urbanization on unit flood discharge using a runoff model for the Tedori River alluvial fan area, Japan. The discharge was studied as collecting runoff from paddy fields, upland crop fields, and residential lots. A runoff model for various land use types in the study area was developed using actual and physical properties of the runoff sites, and parameters for paddy fields. The model was tested using 54 big events and inputted those. The maximum total runoff ratio among different land use types was observed for residential lots, and the ratio remained relatively constant across different flood events. The minimum total runoff ratio was observed for irrigated paddy fields. There was a positive relationship between the total runoff ratio and total precipitation for all land use types. Whereas, the relationship between the peak runoff ratio and peak precipitation was variable. The runoff analysis was carried out using 60-min and 10-min precipitation data. For agricultural land, data for both intervals produced similar results.

关键词： Unit Flood Discharge Total Runoff Ratio Peak Runoff Ratio Runoff Model Depression Storage

Bounded derived categories of very simple manifolds

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Science China Mathematics 2011年第8期54卷 1741-1750页

作者： OGUISO keiji Department of Mathematics Graduate School of ScienceOsaka University Korea Institute for Advanced Study

A non-representable cohomological functor of finite type of the bounded derived category of coherent sheaves of a compact complex manifold of dimension greater than one with no proper closed subvariety is given explic... 详细信息

关键词： derived category cohomological functor very simple manifold

A simple remark on a flat projective morphism with a Calabi-Yau fiber

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Science China Mathematics 2011年第8期54卷 1751-1756页

作者： OGUISO keiji Department of Mathematics Graduate School of ScienceOsaka University Korea Institute for Advanced Study

If a K3 surface is a fiber of a flat projective morphisms over a connected noetherian scheme over the complex number field,then any smooth connected fiber is also a K3 *** this,Professor Nam-Hoon Lee asked if the same is true for higher dimensional Calabi-Yau *** shall give an explicit negative answer to his question in each dimension greater than or equal to three as well as a proof of his initial observation.

关键词： flat projective morphism Hilbert scheme Calabi-Yau manifold

Circuit Implementation of Power Converter for High-Speed Switching Operations

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Chinese Journal of Electrical Engineering 2018年第3期4卷 47-52页

作者： keiji Wada Department of Electronics Engineering and Computer Science Tokyo Metropolitan UniversityTokyo Japan

Recently,high di/dt and dv/dt switching operations of power converter circuits has been discussed for realizing a high-efficiency power converter *** this case,parasitic inductances of the bus bar between a DC capacitor and power devices may cause issues of overshoot voltage and electromagnetic interference(EMI)***,it is necessary to design the bus bar geometry while considering the minimization and optimization of the parasitic inductance of bus *** paper discusses a relationship between bus bar geometry and switching *** addition,the bus bar analysis is based on the PEEC method,and the bus bar geometry is designed by considering the stray inductance with using an inductance-map ***,this paper also presents a design procedure of acceptable stray inductance based on a standardization *** should be noted that the stray inductance is designed not for minimization,but optimization,and it is shown not as an absolute value(H),but as a percentage value(%).Finally,the oscillation waveforms under turn-off operation will be discussed depending on the bus bar geometry.

关键词： Bus bar inductance bus bar geometry circuit implementation EMI switching characteristics

Origin of the Earth:A proposal of new model called ABEL

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Geoscience Frontiers 2017年第2期8卷 253-274页

作者： Shigenori maruyama Toshikazu Ebisuzaki Earth-Life Science Institute Tokyo Institute of Technology Institute for Study of the Earth's Interior Okayama University RIKEN

The Earth was born as a dry planet without atmosphere and ocean components at 4.56 Ga,with subsequent secondary accretion of bio-elements,such as carbon（C）,hydrogen（H）,oxygen（O）,and nitrogen（N） which peaked at 4.37-4.20 *** two-step formation model of the Earth we refer to as the advent of bio-elements model（ABEL Model） and the event of the advent of bio-elements（water component） as ABEL *** is clear that the solid Earth originated from enstatite chondrite-like dry material based on the similarity in oxygen isotopic composition and among other *** the other hand,Earth＇s water derives primarily from carbonaceous chondrite material based on the hydrogen isotopic *** present our ABEL model to explain this enigma between solid Earth and water,as well as secondary accretion of oxidizing bio-elements,which became a precursor to initiate metabolism to emerge life on a highly reductive *** ABEL Bombardment had not occurred,life never would have emerged on the ***,ABEL Bombardment is one of the most important events for this planet to evolve into a habitable *** chronology of ABEL Bombardment is informed through previous researches of the late heavy bombardment and the late veneer *** Bombardment is considered to have occurred during 4.37-4.20 Ga,which is the concept to redefine the standard late heavy bombardment and the late veneer ***,ABEL Bombardment is the trigger of the transition from stagnant lid tectonics to plate tectonics on this planet because of the injection of volatiles into the initial dry Earth.

关键词： Origin of Earth and life Advent of bin-elements (ABEL)Origin of water on the Earth ABEL Bombardment Habitable Trinity planet Initiation of plate tectonics

United theory of biological evolution:Disaster-forced evolution through Supernova,radioactive ash fall-outs,genome instability,and mass extinctions

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Geoscience Frontiers 2015年第1期6卷 103-119页

作者： Toshikazu Ebisuzaki Shigenori maruyama RIKEN 2-1Hirosawa Earth-Life Science Institute Tokyo Institute of Technology

We present the disaster-forced biological evolution model as a general framework that includes Darwinian ＂phylogenic gradualism＂, Eldredge-Gould＇s ＂punctuated equilibrium＂, mass extinctions, and allopatric, parapatric, and sympatric speciation. It describes how reproductive isolation of organisms is established through global disasters due to supernova encounters and local disasters due to radioactive volcanic ash fall-outs by continental alkaline volcanism. Our new evolution model uniquely highlights three major factors of disaster-forced speciation： enhanced mutation rate by higher natural radiation level, smaller population size, and shrunken habitat size （i.e., isolation among the individual pop- ulations）. We developed a mathematical model describing speciation of a half-isolated group from a parental group, taking into account the population size （Ne）, immigration rate （m）, and mutation rate （μ）. The model gives a quantitative estimate of the speciation, which is consistent with the observations of speciation speed. For example, the speciation takes at least 105 generations, if mutation rate is less than 10 3 per generation per individual. This result is consistent with the previous studies, in which μ is assumed to be 10 3-10-5. On the other hand, the speciation is much faster （less than l0S generations） for the case that μ is as large as 0.1 in parapatric conditions （m 〈 μ）. Even a sympatric （m ~ 1 ） speciatiou can occur within 103 generations, if mutation rate is very high （μ- 1 mutation per individual per generation）, and if Ne 〈 20-30. Such a high mutation rate is possible during global disasters due to supernova encounters and local disasters due to radioactive ash fall-outs. They raise natural radiation level by a factor of 100-1000. Such rapid speciation events can also contribute to macro-evolution during mass extinction events, such as observed during the Cambrian explosion of biodiversity. A similar rapid speciation （though in a much smaller scale）

关键词： Speciation Supernova encounter Continental alkaline volcanism Cichlid Great African ape Cambrian explosion

Origins of building blocks of life: A review

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Geoscience Frontiers 2018年第4期9卷 1117-1153页

作者： Norio Kitadai Shigenori maruyama Earth-Life Science Institute Tokyo Institute of Technology

How and where did life on Earth originate？ To date, various environments have been proposed as plausible sites for the origin of life. However, discussions have focused on a limited stage of chemical evolution, or emergence of a specific chemical function of proto-biological systems. It remains unclear what geochemical situations could drive all the stages of chemical evolution, ranging from condensation of simple inorganic compounds to the emergence of self-sustaining systems that were evolvable into modern biological ones. In this review, we summarize reported experimental and theoretical findings for prebiotic chemistry relevant to this topic, including availability of biologically essential elements（N and P） on the Hadean Earth, abiotic synthesis of life＇s building blocks（amino acids, peptides, ribose, nucleobases, fatty acids, nucleotides, and oligonucleotides）, their polymerizations to bio-macromolecules（peptides and oligonucleotides）, and emergence of biological functions of replication and compartmentalization. It is indicated from the overviews that completion of the chemical evolution requires at least eight reaction conditions of（1） reductive gas phase,（2） alkaline pH,（3） freezing temperature,（4）fresh water,（5） dry/dry-wet cycle,（6） coupling with high energy reactions,（7） heating-cooling cycle in water, and（8） extraterrestrial input of life＇s building blocks and reactive nutrients. The necessity of these mutually exclusive conditions clearly indicates that life＇s origin did not occur at a single setting; rather, it required highly diverse and dynamic environments that were connected with each other to allow intratransportation of reaction products and reactants through fluid circulation. Future experimental research that mimics the conditions of the proposed model are expected to provide further constraints on the processes and mechanisms for the origin of life.

关键词： Astrobiology Biochemistry Chemical evolution Extraterrestrial life Hadean Earth Hydrothermal systems

Nuclear geyser model of the origin of life:Driving force to promote the synthesis of building blocks of life

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Geoscience Frontiers 2017年第2期8卷 275-298页

作者： Toshikazu Ebisuzaki Shigenori maruyama RIKEN Earth-Life Science Institute Tokyo Institute of Technology

We propose the nuclear geyser model to elucidate an optimal site to bear the first *** model overcomes the difficulties that previously proposed models have *** geyser is a geyser driven by a natural nuclear reactor,which was likely common in the Hadean Earth,because of a much higher abundance of 235U as nuclear *** nuclear geyser supplies the following：（1）high-density ionizing radiation to promote chemical chain reactions that even tar can be used for intermediate material to restart chemical reactions,（2）a system to maintain the circulation of material and energy,which includes cyclic environmental conditions（warm/cool,dry/wet,etc.）to enable to produce complex organic compounds,（3）a lower temperature than 100℃ as not to break down macromolecular organic compounds,（4）a locally reductive environment depending on rock types exposed along the geyser wall,and（5）a container to confine and accumulate volatile *** five factors are the necessary conditions that the birth place of life must *** the nuclear geyser can meet all five,in contrast to the previously proposed birth sites,such as tidal flat,submarine hydrothermal vent,and outer *** nuclear reactor and associated geyser,which maintain the circulations of material and energy with its surrounding environment,are regarded as the nuclear geyser system that enables numerous kinds of chemical reactions to synthesize complex organic compounds,and where the most primitive metabolism could be generated.

关键词： Origin of life Chemical evolution Natural nuclear reactor Aqueous electron Radiation chemistry