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Detrital zircon geochronology of the Lutzow-Holm Complex,East Antarctica:Implications for Antarctica-Sri Lanka correlation

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Geoscience Frontiers 2018年第2期9卷 355-375页

作者： Yusuke Takamura Toshiaki Tsunogae M.Santosh Yukiyasu tsutsumi Graduate School of Life and Environmental Sciences University of TsukubaIbaraki 305-8572Japan Department of Geology University of JohannesburgAuckland Park 2006South Africa School of Earth Sciences and Resources China University of Geosciences Beijing29 Xueyuan RoadBeijing 100083China Centre for Tectonics Resources and Exploration Department of Earth SciencesUniversity of AdelaideSA 5005Australia Department of Geology and Paleontology National Museum of Nature and ScienceIbaraki 305-0005Japan

The Lützow-Holm Complex(LHC) of East Antarctica has been regarded as a collage of Neoarchean(ca.2.5 Ga), Paleoproterozoic(ca. 1.8 Ga), and Neoproterozoic(ca. 1.0 Ga) magmatic arcs which were amalgamated through the latest Neoproterozoic collisional events during the assembly of Gondwana supercontinent. Here, we report new geochronological data on detrital zircons in metasediments associated with the magmatic rocks from the LHC, and compare the age spectra with those in the adjacent terranes for evaluating the tectonic correlation of East Antarctica and Sri Lanka. Cores of detrital zircon grains with high Th/U ratio in eight metasediment samples can be subdivided into two dominant groups:(1) late Meso-to Neoproterozoic(1.1-0.63 Ga) zircons from the northeastern part of the LHC in Prince Olav Coast and northern Soya Coast areas, and(2) dominantly Neoarchean to Paleoproterozoic(2.8-2.4 Ga) zircons from the southwestern part of the LHC in southern Lutzow-Holm Bay area. The ca.1.0 Ga and ca. 2.5 Ga magmatic suites in the LHC could be proximal provenances of the detrital zircons in the northeastern and southwestern LHC, respectively. Subordinate middle to late Mesoproterozoic(1.3-1.2 Ga) detrital zircons obtained from Akarui Point and Langhovde could have been derived from adjacent Gondwana fragments(e.g., Rayner Complex, Eastern Ghats Belt). Meso-to Neoproterozoic domains such as Vijayan and Wanni Complexes of Sri Lanka, the southern Madurai Block of southern India, and the central-western Madagascar could be alternative distal sources of the late Meso-to Neoproterozoic zircons. Paleo-to Mesoarchean domains in India, Africa, and Antarctica might also be distal sources for the minor ~2.8 Ga detrital zircons from Skallevikshalsen. The detrital zircons from the Highland Complex of Sri Lanka show similar Neoarchean to Paleoproterozoic(ca. 2.5 Ga) and Neoproterozoic(ca. 1.0 Ga) ages, which are comparable with those of the LHC, suggesting that the two complexes might have form

关键词： The northern Lützow-Holm-Vijayan Complex Zircon U-Pb geochronology Crustal evolution Tectonic correlations Gondwana supercontinent

Ongoing Applicative Studies of Plant Thioredoxins

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Molecular Plant 2014年第1期7卷 4-13页

作者： hiroyuki Yano National Food Research Institute National Agriculture and Food Research Organization Kannondai 2-1-12 Tsukuba Ibaraki 305-8642 Japan

Studies triggered by the discovery of the function of thioredoxin （Trx） in photosynthesis have revealed its role throughout biology. Parallel biochemical and proteomic analyses have led to the identification of its numerous puta- tive targets. Recently, to verify the biological significance of these targets, in vivo studies using transformants in which Trx is overexpressed or suppressed are in progress, and the transformants themselves that are being used in such studies show their potential applicative values. Moreover, Trx＇s mitigation of allergenicity for some proteins offers promising prospects in the food industry. Practical studies based on redox regulation, once only on the horizon, are now achieving new dimensions. This short review focuses on the industrial applications of Trx studies, the current situation, and future perspectives. The putative targets obtained by the proteomics approach in comparison with in vivo observations of the transformants are also examined. Applicative studies of glutathione, a counterpart of Trx, are also discussed briefly.

关键词： allergen food redox regulation target thioredoxin.

Seed germination and dormancy: The classic story, new puzzles, and evolution

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Journal of Integrative Plant Biology 2019年第5期61卷 541-563页

作者： hiroyuki Nonogaki Department of Horticulture Oregon State University

This review highlights recent progresses in seed germination and dormancy *** on the weakening of the endosperm during germination,which is almost a classic theme in seed biology,was resumed byα-xylosidase *** genetic evidence was presented to suggest that the quality control of xyloglucan biosynthesis in the endosperm(and the embryo)plays a critical role in *** analyses on the endosperm and the adjace nt layers have suggested that the cutin coat in the endosperm-testa interphase negatively affects germination while the en dosperm-embryo in terphase produces a sheath that facilitates *** progresses significantly advanced our understanding of seed germination mechanisms.A breakthrough in dormancy research,on the other hand,revealed the unique abscisic acid signaling pathway that is regulated by DELAY OF GERMINATION1(DOG1).The detailed analysis of DOC1 expression uncovered the intriguing story of reciprocal regulation of the sensean tisense pair,which gen erated new *** studies also suggested that the DOG1 function is not limited to dormancy but extended through general seed maturation,which provokes questions about the evolution of DOG1 family *** biology is becoming more exciting with the classic stories being revitalized and new puzzles emerging from the frontier.

关键词： highlights recent germination and dormancy emerging from the frontier

Ghrelin and Helicobacter pylori infection

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World Journal of Gastroenterology 2008年第41期14卷 6327-6333页

作者： hiroyuki Osawa Department of Internal Medicine Division of Gastroenterology Jichi Medical University

Ghrelin is primarily secreted from the stomach and has been implicated in the coordination of eating behavior and weight regulation. Ghrelin also plays an essential role in the mechanism of gastric mucosal defense. Thus, it is important to clarify which diseases primar- ily influence changes in plasma ghrelin concentrations. Helicobacter pylori （H pylor/~ infection is involved in the pathogenesis of gastritis, gastric and duodenal ulcer, gastric carcinoma, and mucosa-associated lym- phoid tissue lymphoma. H pylori eradication is related to body weight change. Compared, H pylori infected and negative subjects with normal body mass index, plasma ghrelin concentration, gastric ghrelin mRNA, and the number of ghrelin producing cells in gastric mucosa are significantly lower in Hpylori infected sub- jects than in Hpylori-negative controls. Plasma ghrelin concentration decreases with the progression of gastric atrophy. Impaired gastric ghrelin production in associa- tion with atrophic gastritis induced by Hpylori infection accounts for the decrease in plasma ghrelin concentra- tion. However, the ratio of plasma acylated ghrelin to total ghrelin levels is higher in patients with chronic atrophic gastritis than in healthy subjects. This may re- sult from the＇ compensatory increase in plasma active ghrelin concentration in response to gastric atrophy. After H pylori eradication, gastric preproghrelin mRNA expression is increased nearly 4-fold in most cases. However, changes in plasma ghrelin concentrations be- fore and after Hpylori cure are not associated with the gastric ghrelin production. Plasma ghrelin changes are inversely correlated with both body weight change and initial plasma ghrelin levels.

关键词： Ghrelin Helicobacter pylori Eradication Body weight Leptin

Petrochemistry and Zircon U-Pb Geochronology of Felsic Xenoliths in Late Cenozoic Gem-Related Basalt from Bo Phloi Gem Field, Kanchanaburi, Western Thailand

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Journal of Earth Science 2021年第4期32卷 1035-1052页

作者： Alongkot Fanka Chidchanok Kasiban Toshiaki Tsunogae Yukiyasu tsutsumi Chakkaphan Sutthirat Department of Geology Faculty of ScienceChulalongkorn UniversityPathumwanBangkok 10330Thailand Graduate School of Life and Environmental Sciences University of TsukubaIbaraki 305-8572Japan Department of Geology University of JohannesburgAuckland Park 2006South Africa Department of Geology and Paleontology National Museum of Nature and ScienceIbaraki 305-0005Japan

The Cenozoic basalts exposed in Bo Phloi Gem Field,Kanchanaburi Province,western Thailand are a host to different gem materials(e.g.,sapphire,black spinel,black pyroxene and zircon)as well as other xenocrysts and xenoliths from the deep-seated formations onto the earth ***,only felsic xenoliths have never been investigated and reported in detail though they are in fact significant evidence of ancient tectonic processes of this *** this study,the felsic xenoliths were sampled and classified,on the basis of petrochemistry,into granite,syenogranite,and ***,they contain similar mineral assemblages including essentials of quartz,K-feldspar,and plagioclase with different proportions and accessories of biotite,zircon,and opaque ***,large phenocrysts of K-feldspar and plagioclase commonly present as a primary texture which are frequently corroded and replaced by‘sieved texture’with secondary cumulative fringe of tiny feldspar and *** secondary textures clearly indicate quenching after re-heating during transportation by basaltic *** analyses indicate that the alkaline and peraluminous magma show enrichment of Rb and depletion of Ba,Nb,Ta,Ti with steep slope of LREE/HREE enrichment *** evidences suggest low-degree partial melting of crustal materials related to the collisional S-type granite *** addition,U-Pb dating of zircon from a felsic xenolith yields 211.6±1.3 Ma comparable to the Late Triassic magmatism of the central belt granite in this region which is resulted from the collision between Sibumasu and Indochina terranes.

关键词： basalt granite sapphire tectonic Thailand xenolith

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Study of excited nucleon states at EBAC:status and plans

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Chinese Physics C 2009年第12期33卷 1077-1084页

作者： hiroyuki Kamano Excited Baryon Analysis Center (EBAC) Thomas Jefferson National Accelerator Facility Newport News VA 23606 USA

We present an overview of a research program for the excited nucleon states in Excited Baryon Analysis Center （EBAC） at Jefferson Lab. Current status of our analysis of the meson production reactions based on the unitary dynamical coupled-channels model is summarized, and the N＊ pole positions extracted from the constructed scattering amplitudes are presented. Our plans for future developments are also discussed.

关键词： dynamical coupled-channels analysis meson production reactions N* pole positions

Gastric linitis plastica with autoimmune pancreatitis diagnosed by an endoscopic ultrasonography-guided fine-needle biopsy: A case report

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World Journal of Clinical Cases 2022年第31期10卷 11607-11616页

作者： Ryosuke Sato Kazuyuki Matsumoto Hiromitsu Kanzaki Akihiro Matsumi Kazuya Miyamoto Kosaku Morimoto hiroyuki Terasawa Yuki Fujii Tatsuhiro Yamazaki Daisuke Uchida Koichiro tsutsumi Shigeru Horiguchi Hironari Kato Gastroenterology and Hepatology Okayama University HospitalOkayama 700-8558Japan

BACKGROUND Gastric linitis plastica(GLP)is a subset of gastric cancer with a poor *** is difficult to obtain a definitive diagnosis by endoscopic mucosal biopsies,and the usefulness of an endoscopic ultrasonography-guided fine-needle biopsy(EUSFNB)for GLP has been recently ***,autoimmune diseases are occasionally known to coexist with malignant tumors as paraneoplastic *** herein report the usefulness of an EUS-FNB for detecting GLP and the possibility of paraneoplastic syndrome coexisting with *** SUMMARY An 81-year-old man was admitted to our hospital for a 1-mo history of epigastric pain that increased after *** laboratory data revealed high levels of serum carbohydrate antigen 19-9 and *** examinations showed giant gastric folds and reddish mucosa;however,no epithelial changes were *** gastric lumen was not distensible by air inflation,suggesting *** tomography showed the thickened gastric wall,the diffuse enlargement of the pancreas,and the peripancreatic rim,which suggested autoimmune pancreatitis(AIP)coexisting with *** the pathological findings of the endoscopic biopsy showed no malignancy,he underwent an EUSFNB and was diagnosed with *** received chemotherapy for unresectable gastric cancer due to peritoneal metastasis,after which both the gastric wall thickening and diffuse enlargement of the pancreas were *** An EUS-FNB for GLP with a negative endoscopic biopsy is useful,and AIP may develop as a paraneoplastic syndrome.

关键词： Endoscopic ultrasound-guided fine needle aspiration Linitis plastica Autoimmune pancreatitis Paraneoplastic syndromes Case report

Analysis of Grassland Vegetation of the Southwest Heilongjiang Steppe （China） Using the Power Law

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Journal of Integrative Plant Biology 2005年第8期47卷 917-926页

作者： Mikinori TSUIKI Yu-Sheng WANG Yiruhan Michio tsutsumi Masae SHIYOMI Faculty of Agriculture lwate University Morioka 020-8550 Japan National Northeast Agricultural University Harbin 150030 China Environmental Engineering Department College of Science and Engineering Jinan University Guangzhou 510630 China National Institute of Livestock and Grassland Science Ecology Department Tochigi 329-2724 Japan Faculty of Science lbaraki University Mito 310-8512 Japan

In 1997, we conducted a vegetation survey in three semi-arid natural grasslands （steppes） with different livestock grazing intensities in Southwest Heilongjiang Province, China, The dominant grassland species was the grass Stipa baicalensis Roshev. Grasslands with light, intermediate, and heavy grazing intensities were located 10, 5, and 2 km from a village, respectively. Villagers use the steppe to raise cattle, horses, sheep, and goats. Each of the three grasslands was surveyed by placing 100 quadrats （50 cm×50 cm） along a 50 m line transect. Each quadrat was divided into four equal areas （25 cm×25 cm; S-quadrats） and all plant species occurring in each of these smaller areas were identified and recorded. These data were summarized into frequency distributions and the percentage of S-quadrats containing a given species and the variance of each species were estimated. The power law was applied to these estimates. The power law was used to evaluate the spatial heterogeneity and frequency of occurrence for each species in the grassland community. The lightly grazed grassland exhibited high spatial heterogeneity （caused by large plant size）, the highest species diversity, and a high occurrence of S. baicalensis. In contrast, the heavily grazed grassland exhibited high spatial heterogeneity （caused by patchy populations of small plant size）, low species diversity, and a low occurrence of S. baicalensis. We judged that the heavily grazed grassland was overgrazed and exclusion of livestock from the degraded areas is necessary for recovery.

关键词： degradation grazing intensity Heilongjiang (China) spatial heterogeneity species diversity steppe Stipa baicalensis.

Heat transfer in a tapered fluidized bed of biomass particles with pulsed gas flow

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Particuology 2019年第1期17卷 2-14页

作者： Dening Jia Xiaotao Bi C. Jim Lim Shahab Sokhansanj Atsushi tsutsumi Department of Chemical and Biological Engineering The University of British Columbia2360 East MallVancouverBCV6T 1Z3Canada Environmental Sciences Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Collaborative Research Center for Energy Engineering Institute of Industrial ScienceThe University of Tokyo4-6-1 KomabaMeguro-kuTokyo 153-8505Japan

Bed-to-surface heat transfer of pure biomass particles in a pulsed fluidized bed with a tapered bottom section was investigated. Three biomass species — Douglas fir, pine, and switchgrass — were studied under various operating conditions. Their heat transfer coefficients were found to be closely associated with hydrodynamics dominated by gas pulsations. A higher superficial gas velocity generally yielded better gas–solid contact and higher heat transfer rates. A moderately increasing pulsation frequency promoted convective heat transfer of particles but also reduced pulsation intensity, leading to undesired flow behaviours such as channelling and partial defluidization. The study of the pulsation duty cycle revealed that, for cohesive particles, a smaller duty cycle was preferred to generate powerful pulsations to break up inter-particle forces. Moreover, a duty cycle increase allowed higher gas throughput as long as a suitable fluidization was maintained. The addition of finer particles to a coarse fraction increased particle mobility, and subsequently heat transfer, which also explained the higher heat transfer coefficients of switchgrass as it contained more fines compared with fir and pine. Experimental results in the tapered bed were also compared with those of non-tapered geometry where a 10%–20% increase in heat transfer was observed.

关键词： Fluidized bed Gas pulsations Tapered column Heat transfer Biomass