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Chloroplast DNA variation and phylogeography of Ligularia tongolensis (Asteraceae), a species endemic to the Hengduan Mountains region of China

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Journal of Systematics and Evolution 2011年第2期49卷 108-119页

作者： chiaki KURODA Department of Chemistry Rikkyo University

In this research, we aimed to study the genetic variation and phylogeographic pattern of Ligularia tongolensis, a perennial herb endemic to the Hengduan Mountains region of China. We sequenced two chloroplast DNA (cpDNA) intergenic spacers (trnQ-5 rps16, trnL-rpl32) in 140 individuals from 14 populations of three groups (Jinshajiang vs. Yalongjiang vs. Wumeng) within this species range. High levels of haplotype diversity (Hd = 0.814) and total genetic diversity (Ht = 0.862) were detected at the species level, based on a total of 12 haplotypes identified. Low levels of intrapopulation diversity (Hs = 0.349), high levels of genetic divergence (Gst = 0.595, Nst = 0.614, Fst = 0.597), and the absence of isolation by distance tests were also found in L. tongolensis. Furthermore, H2 and H5, the dominant haplotypes that located at internal nodes and deviated from extinct ancestral haplotype in the network, were found to be shared between Jinshajiang and Yalongjiang groups. These results indicate that past fragmentation may be the important factor responsible for the present phylogeographical pattern of L. tongolensis. Meanwhile, the locations occupied by each group might have served as independent refugia for L. tongolensis during the Quaternary glaciation. Unimodal mismatch distribution and star-like genealogies indicated this species underwent past demographic expansion events, with expansion ages of 274 ka BP.

关键词： genetic variation Ligularia tongolensis phylogeography Quaternary glaciation.

Natural hybridization and introgression in sympatric Ligularia species(Asteraceae,Senecioneae)

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Journal of Systematics and Evolution 2011年第5期49卷 438-448页

作者： chiaki KURODA Department of Chemistry Rikkyo University

The difficulty in clarifying species of genus Ligularia *** been attributed to rapid and continuous allopatric speciation in small and isolated populations,combined with interspecific diploid hybridization in the Qinghai-Tibetan Plateau and adjacent ***,no concrete example has been reported to prove this *** studied a natural mixed population of six species of Ligularia in which some individuals were morphologically intermediate between *** and *** on DNA sequences(trnC-F,trnL-rpL32,trnQ5 rps16,trnK-rps16,and internal transcribed spacer) and inter-simple sequence repeat data,we concluded that putative hybrids are primarily products of hybridization between *** and *** other four species or additional,unknown species may also be involved in *** hybridization is bidirectional but *** individuals were mostly the first generation,but F2 and later-generation hybrids were also ***,the backcrossed individuals detected indicate that natural gene flow occurs among at least three Ligularia *** may become stabilized to form new species or may function as intermediates in evolutionary diversification.

关键词： chloroplast fragments ISSR markers Ligularia natural hybridization nuclear ribosomal ITS.

Shock Train and Pseudo-shock Phenomena in Supersonic Internal Flows

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Journal of Thermal Science 2003年第3期12卷 204-208,197页

作者： Kazuyasu matsuo Department of Mechanical Systems and Environmental Engineering. Faculty of Environmental Engineering.University of Kitakyushu Hibikino Wakamatsu Kitakyushu 808-0135 Japan

When a normal shock wave interacts with a boundary layer along a wall surface in supersonic internal flows and the shock is strong enough to separate the boundary layer, the shock is bifurcated and a series of shocks called “shock train” is formed. The flow is decelerated from supersonic to subsonic through the whole interaction region that is referred to as “pseudo-shock”. In the present paper some characteristics of the shock train and pseudo-shock and some examples of the pseudo-shocks in some flow devices are described.

关键词： shock wave shock train pseudo-shock supersonic flow internal flow.

Adsorption of ^133Cs and ^87Sr on pumice tuff：A comparative study between powder and intact solid phase

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Acta Geochimica 2017年第2期36卷 224-231页

作者： Mohammad Rajib chiaki T.Oguchi Graduate School of Science and Engineering Saitama University 255 Shimo Okubo Sakura ku Saitama shi Saitama 338-8570 Japan Bangladesh Atomic Energy Commission Paramanu Bhaban E-12/A Sher-e-Banglanagar Dhaka 1207 Bangladesh Department of Civil and Environmental Engineering Saitama University 255 Shimo Okubo Sakura ku Saitama shi Saitama 338-8570 Japan

This study examines the use of intact samples as an alternative to powder in conventional batch sorption studies to determine the distribution coefficient(K_d).Stable cesium(^(133)Cs) and strontium(^(87)Sr) were used under specified geochemical conditions to compare the Kdvalues of powder and block pumice tuff samples. The aim of the study was to infer any Kddifference under laboratory and field conditions. Kdvalues for block samples were found to be less than one order of magnitude lower than powder materials for both Cs and Sr on fresh tuff, and more than one order of magnitude lower in oxidized tuff. Destruction of micropores in oxidized tuff was estimated to be mainly responsible for reducing Kdvalues in oxidized tuff. However, approximately one order of magnitude difference in Kdvalues indicates that homogenously prepared intact samples can be used for sorption coefficient measurement at closer to in situ conditions. Pore size distribution analysis using mercury intrusion porosimetry revealed that lower Kdvalues on block samples result from lower surface area available as sorption sites due to inaccessible closed pores in the intact solid.

关键词： Cesium Strontium Pumice tuff Adsorption

Rebuilding insight into the pathophysiology of Alzheimer’s disease through new blood-brain barrier models

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Neural Regeneration Research 2024年第9期19卷 1954-1960页

作者： Kinya matsuo Hideaki Nshihara Yamaguchi University Graduate School of Medicine YamaguchiJapan Department of Neurotherapeutics Yamaguchi UniversityUbeJapan

The blood-brain barrier is a unique function of the microvasculature in the brain parenchyma that maintains homeostasis in the central nervous ***-brain barrier breakdown is a common pathology in various neurological diseases,such as Alzheimer’s disease,stroke,multiple sclerosis,and Parkinson’s ***,it has been considered a consequence of neuroinflammation or neurodegeneration,but recent advanced imaging techniques and detailed studies in animal models show that blood-brain barrier breakdown occurs early in the disease process and may precede neuronal ***,the blood-brain barrier is attractive as a potential therapeutic target for neurological diseases that lack effective *** elucidate the molecular mechanism underlying blood-brain barrier breakdown and translate them into therapeutic strategies for neurological diseases,there is a growing demand for experimental models of human origin that allow for functional ***,several human induced pluripotent stem cell-derived blood-brain barrier models have been established and various in vitro blood-brain barrier models using microdevices have been *** in the Alzheimer’s disease field,the human evidence for blood-brain barrier dysfunction has been demonstrated and human induced pluripotent stem cell-derived blood-brain barrier models have suggested the putative molecular mechanisms of pathological blood-brain *** this review,we summarize recent evidence of blood-brain barrier dysfunction in Alzheimer’s disease from pathological analyses,imaging studies,animal models,and stem cell ***,we discuss the potential future directions for blood-brain barrier research.

关键词： Alzheimer’s disease blood-brain barrier human induced pluripotent stem cells

Challenges for beyond 5G:ultra-densification of radio access network

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通信学报 2020年第11期41卷 1-11页

作者： Fumiyuki Adachi Ryo Takahashi Hidenori matsuo Research Organization of Electrical Communication Tohoku UniversitySendai 980-8577Japan

Ultra-densification of radio access network(RAN)is a key to efficiently support the exponentially growing mobile data traffic in 5 G ***,extremely high frequency band like mm Wave band was utilized to solve the bandwidth shortage ***,untra-dense reusing the same radio resource produced severe *** the mm Wave link was very harsh due to frequent blockage by *** a new RAN architecture needed to be introduced to realize ultra-reliable communications in such a severe radio propagation *** architecture of distributed MIMO based RAN was ***,enhanced interference coordination(e IC)was ***,the effectiveness of distributed MIMO based RAN with e IC by computer simulation was showed.

关键词： 5G advanced systems distributed MIMO radio access network interference coordination cooperative signal transmission

Incompressible SPH simulation of solitary wave propagation on permeable beaches

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Journal of Hydrodynamics 2020年第4期32卷 664-671页

作者： chiaki Tsurudome Dongfang Liang Yuma Shimizu Abbas Khayyer Hitoshi Gotoh Department of Engineering University of CambridgeTrumpington StreetCambridgeUK Graduate School of Engineering Kyoto UniversityKyotoJapan

Wave propagation on uniformly sloped beaches is a canonical coastal engineering topic that has been studied extensively in the past few ***,most of these studies treat beaches as solid boundaries even though they are often made of porous materials,such as sediment and *** beaches struck by tsunami-like waves have not been adequately *** is expected that the degree of penneability plays a crucial role in mitigating the impact of the *** study examines solitary wave run-ups on sandy beaches using an incompressible smoothed particle hydrodynamics(ISPH)*** permeability of the beach is considered to be directly related to the diameter of its constituent sand *** obtain a satisfactory pressure field,which cannot be achieved using the original ISPH algorithm,the source term of the pressure Poisson equation has been modified based on a higher-order source-term *** within the porous medium are computed in the same framework as those outside the porous *** the current model,no transition zone is needed at the boundary of the porous *** wave-attenuation effect of the porous medium is discussed,with a particular focus on the relationship between the mn-up height and grainsize.

关键词： Solitary wave porosity incompressible smoothed particle hydrodynamics(ISPH) run-up

Possible application of apolipoprotein E-containing lipoproteins and polyunsaturated fatty acids in neural regeneration

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Neural Regeneration Research 2016年第5期11卷 715-716页

作者： Michinori matsuo Department of Food and Nutrition Faculty of Home Economics Kyoto Women's University

Neuronal degeneration is a social and health problem,because of high incidence of acute injury,stroke,and neurodegenerative disorders,such as Alzheimer＇s disease and Parkinson＇s *** regeneration is crucial for promo... 详细信息

关键词： PUFAs

Geochemical behavior of rare-earth elements and other major and minor elements in sound-producing and silent beach sands in Japan

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Chinese Journal Of Geochemistry 2007年第1期26卷 35-45页

作者： chiaki Igarashi Naotatsu Shikazono Haruhiro Otani Graduate School of Science and Technology Keio University3-14-1 HiyoshiKohoku-kuYokohama223-8522Japan Faculty of Science and Technology Department of Applied ChemistryEnvironmental GeochemistryKeio University3-14-1 HiyoshiKohoku-kuYokohama223-8522Japan

The major element composition of sound-producing sand is reported together with rare-earth elements (REE) and other selected elements for the first time. Rare-earth element concentrations in beach sands from Miyagi and Tottori in Japan were determined by induction-coupled, argon-plasma spectrometry (ICP-MS) to characterize the REE of sound-producing and silent sands relative to the parental rocks. Sound-producing sand beaches are very common and all over in Japan: five beaches in Miyagi and 2 in Tottori are selected with other silent sand beaches in the areas. Both sound-producing sand and silent sand samples from Miyagi and Tottori contain more than 60wt% of SiO2 and are composed mainly of quartz and feldspar. Miyagi sand samples are characterized by light REE enrichment and flat chondrite-normalized patterns that are similar to those of local source sandstone. However, all sand samples from Miyatojima in Miyagi show positive Eu anomalies, a characteristic feature not shown in other sand samples from Miyagi. Tottori sand samples also are characterized by high REE contents and remarkable positive Eu anomalies. The sands containing lower REE contents are due to high quartz and feldspar contents. Miyatojima sand samples and Tottori sand samples have high REE contents and show remarkable positive Eu anomalies due to the presence of feldspar. The best results are obtained using all of the geological methods and the Principal Component Analysis (PCA) as a measure of the similarity between sound-producing sand and silent sand. The difference between sound-producing sand and silent sand is obtained from the PCA results.

关键词：日本发声沙滩无声沙滩稀土元素常量元素微量元素地球化学行为