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Paradoxical reduction of cerebral blood flow after acetazolamide loading:a hemodynamic and metabolic study with ^(15)O PET

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Neuroscience Bulletin 2014年第5期30卷 845-856页

作者： Tadashi Watabe Eku Shimosegawa Hiroki Kato Kayako Isohashi Mana Ishibashi mitsuaki tatsumi Kazuo Kitagawa Toshiyuki Fujinaka Toshiki Yoshimine Jun Hatazawa Department of Molecular Imaging in Medicine Department of Nuclear Medicine Department of Nuclear Medicine and Tracer Kinetics Stroke Center Osaka University Hospital Department of Radiology Department of Neurology Department of Neurosurgery Osaka University Graduate School of Medicine

Paradoxical reduction of cerebral blood flow （CBF） after administration of the vasodilator acetazolamide is the most severe stage of cerebrovascular reactivity failure and is often associated with an increased oxygen extraction fraction （OEF）. In this study, we aimed to reveal the mechanism underlying this phenomenon by focusing on the ratio of CBF to cerebral blood volume （CBV） as a marker of regional cerebral perfusion pressure （CPP）. In 37 patients with unilateral internal carotid or middle cerebral arterial （MCA） steno-occlusive disease and 8 normal controls, the baseline CBF （CBFb）, CBV, OEF, cerebral oxygen metabolic rate （CMRO2）, and CBF after acetazolamide loading in the anterior and posterior MCA territories were measured by （15）~O positron emission tomography. Paradoxical CBF reduction was found in 28 of 74 regions （18 of 37 patients） in the ipsilateral hemisphere. High CBFb （〉47.6 mL/100 mL/min, n = 7） was associated with normal CBFb/CBV, increased CBV, decreased OEF, and normal CMRO2. Low CBFb （〈31.8 mL/100 mL/min, n = 9） was associated with decreased CBFb/CBV, increased CBV, increased OEF, and decreased CMRO2. These findings demonstrated that paradoxical CBF reduction is not always associated with reduction of CPP, but partly includes high- CBFb regions with normal CPP, which has not been described in previous studies.

关键词： acetazolamide cerebral blood flowparadoxical reduction positron emission tomographyvasodilatation

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^15O-PET定量显像评价默认模式神经网络:脑血流与氧代谢的比较研究

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中华核医学与分子影像杂志 2018年第12期38卷 839-840页

作者：唐军(译) Jo Aoe Tadashi Watabe Eku Shimosegawa Hiroki Kato Yasukazu Kanai Sadahiro Naka Keiko Matsunaga Kayako Isohashi mitsuaki tatsumi Jun Hatazawa 上海交通大学医学院附属苏州九龙医院核医学科 215021 Department of Nuclear Medicine and Tracer Kinetics Osaka University Graduate School of MedicineSuita Japan

目的静息态功能磁共振成像(rs-fMRI)通过基于血氧水平依赖(BOLD)信号的自发振荡发现了默认模式神经网络(DMN)的存在。BOLD信号反映了脱氧血红蛋白的浓度,而该浓度依赖于局部脑血流(CBF)和脑氧代谢率(CMRO2)的关系。但是,这两者在rs-fMR... 详细信息

目的静息态功能磁共振成像(rs-fMRI)通过基于血氧水平依赖(BOLD)信号的自发振荡发现了默认模式神经网络(DMN)的存在。BOLD信号反映了脱氧血红蛋白的浓度,而该浓度依赖于局部脑血流(CBF)和脑氧代谢率(CMRO2)的关系。但是,这两者在rs-fMRI时无法区分。研究者尝试通过15O标记气体和水的定量PET显像分析DMN的功能相关区域,并比较CBF和CMRO2在发现DMN功能相关区域中的作用。方法9名正常志愿者[男5名,女4名,年龄(47.0±1.2)岁]行^15O-O2、^15O-CO气体和^15O-H2O的PET显像。通过自动显影法并转换成蒙特利尔神经病学研究所(MNI)标准化脑模板获得定量CBF和CMRO2图像。根据已完成的rs-fMRI图像于标化PET图像上设置感兴趣区(ROI)。在DMN功能相关区域分析中,对脑内所有成对的区域计算其Pearson相关系数(r),同时获得CBF和CMRO2各自发现的功能相关区域的分布图。本研究定义r>0.7为显著正相关,比较CBF和CMRO2各自的功能相关区域的分布图。结果CBF显像时在24对局部脑区域中发现显著正相关(r>0.7),而CMRO2显像时发现22对,两者间有12对神经网络区域是重复的。

关键词：默认模式神经网络功能相关性 ^15O PET 脑血流脑氧代谢率

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Tree diversity effects on forest productivity increase through time because of spatial partitioning

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Forest Ecosystems 2020年第3期7卷 327-333页

作者： Shinichi tatsumi Department of Biological Sciences University of Toronto ScarboroughTorontoONCanada Hokkaido Research Center Forestry and Forest Products Research InstituteHokkaidoJapan

Background: Experimental manipulations of tree diversity have often found overyielding in mixed-species plantations. While most experiments are still in the early stages of stand development, the impacts of tree diversity are expected to accumulate over time. Here, I present findings from a 31-year-old tree diversity experiment(as of2018) in ***: I find that the net diversity effect on stand biomass increased linearly through time. The species mixture achieved 64% greater biomass than the average monoculture biomass 31 years after planting. The complementarity effect was positive and increased exponentially with time. The selection effect was negative and decreased exponentially with time. In the early stages(≤ 3 years), the positive complementarity effect was explained by enhanced growths of early-and mid-successional species in the mixture. Later on(≥ 15 years), it was explained by their increased survival rates owing to vertical spatial partitioning — i.e. alleviation of self-thinning via canopy stratification. The negative selection effect resulted from suppressed growths of late-successional species in the bottom ***: The experiment provides pioneering evidence that the positive impacts of diversity-driven spatial partitioning on forest biomass can accumulate over multiple decades. The results indicate that forest biomass production and carbon sequestration can be enhanced by multispecies afforestation strategies.

关键词： Biomass productivity Complementarity effect Biodiversity and ecosystem functioning Forest dynamics Mixed plantation Plant succession Selection effect Shade tolerance Stand structure Tree diversity experiment

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Making continental crust:The sanukitoid connection

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Chinese Science Bulletin 2008年第11期53卷 1620-1633页

作者： Yoshiyuki tatsumi Institute for Research on Earth Evolution (IFREE) Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Yokosuka 237-0061 Japan

The average continental crust possesses intermediate compositions that typify arc magmatism and as a result it is believed to have been created at ancient convergent plate boundaries. One possible mechanism for intermediate continental crust formation is the direct production of andesitic melts in the upper mantle. Sanukitoids, which characterize the Setouchi volcanic belt, SW Japan, include un-usually high-Mg andesites (HMA). They were generated by slab melting and subsequent melt-mantle interactions under unusual tectonic settings such as where warm lithosphere subducts into hot upper mantle. Such conditions would have existed in the Archean. Hydrous HMA magmas are likely to have solidified within the crust to form HMA plutons, which were then remelted to produce differentiated sanukitoids. At present, generation and differentiation of HMA magmas may be taking place in the Izu-Bonin-Mariana arc-trench system (IBM), because (1) HMA magmatism characterizes the initial stages of the IBM evolution and (2) the IBM middle crust exhibits Vp identical to that of the bulk conti-nental crust. Vp estimates for plutonic rocks with HMA compositions support this. However tonalitic composition for middle-crust-forming rocks cannot be ruled out, suggesting an alternative possibility that the continental crust has been created by differentiation of mantle-derived basaltic magmas.

关键词：赞岐状岩大陆壳地质学地质运动

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Prediction of Photosynthetic Carbon Assimilation Rate of Individual Rice Leaves under Changes in Light Environment Using BLSTM-Augmented LSTM

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Computer Modeling in Engineering & Sciences 2022年第12期133卷 557-577页

作者： Masayuki Honda Kenichi tatsumi Masaki Nakagawa Graduate School of Bio-Applications and Systems Engineering Tokyo University of Agriculture and TechnologyKoganei City184-8588Japan Institute of Agriculture Tokyo University of Agriculture and TechnologyFuchu City183-0054Japan Institute of Engineering Tokyo University of Agriculture and TechnologyKoganei City184-8588Japan

A model to predict photosynthetic carbon assimilation rate(A)with high accuracy is important for forecasting crop yield and *** short-term memory(LSTM),a neural network suitable for time-series data,enables prediction with high accuracy but requires mesophyll *** addition,for practical use,it is desirable to have a technique that can predict A from easily available *** this study,we propose a BLSTM augmented LSTM(BALSTM)model,which utilizes bi-directional LSTM(BLSTM)to indirectly reproduce the mesophyll variables required for *** most significant feature of the proposed model is that its hybrid architecture uses only three relatively easy-to-collect external environmental variables—photosynthetic photon flux density(Q_(in)),ambient CO_(2) concentration(C_(a)),and temperature(T_(air))—to generate mesophyll CO_(2) concentration(C_(i))and stomatal conductance to water vapor(g_(sw))as intermediate ***,A is predicted by applying the obtained intermediate outputs to the learning ***,in this study,1)BALSTM(Q_(in),C_(a),T_(air))had a significantly higher A prediction accuracy than LSTM(Q_(in),C_(a),T_(air))in case of using only Q_(in),C_(a),and T_(air);2)BALSTMC_(i),g_(sw),which had C_(i) and g_(sw) as intermediate products,had the highest A prediction accuracy compared with other candidates;and 3)for samples where LSTM(Q_(in),C_(a),T_(air))had poor prediction accuracy,BALSTMC_(i),g_(sw)(Q_(in),C_(a),T_(air))clearly improved the ***,it was found that incorrect predictions may be formed when certain factors are not reflected in the data(e.g.,timing,cultivar,and growth stage)or when the training data distribution that accounts for these factors differs from the predicted data ***,a robust model should be constructed in the future to improve the prediction accuracy of A by conducting gasexchange measurements(including a wide range of external environmental values)and by increasing the

关键词： Hybrid prediction model assimilation rate leaf internal variables recurrent neural network fluctuating light environments rice

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二甲醚的电催化氧化反应

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催化学报 2003年第9期24卷 695-700页

作者：王世忠 tatsumi ISHIHARA 厦门大学化学系福建厦门361005 大分大学应用化学系

考察了负载于镓酸镧基电解质上的镍电极与镍钐掺杂氧化铈复合电极电催化二甲醚氧化反应的特性 .结果表明 ,反应的主要产物均为CO ,H2 和CH4,同时生成少量完全氧化的产物H2 O和CO2 .在开路电位下二甲醚发生裂解反应 ,生成的CO ,H2 和CH... 详细信息

考察了负载于镓酸镧基电解质上的镍电极与镍钐掺杂氧化铈复合电极电催化二甲醚氧化反应的特性 .结果表明 ,反应的主要产物均为CO ,H2 和CH4,同时生成少量完全氧化的产物H2 O和CO2 .在开路电位下二甲醚发生裂解反应 ,生成的CO ,H2 和CH4三种主要产物的比例接近于 1.在有电泵氧存在下 ,二甲醚的电催化氧化反应强烈地依赖于阳极及电解质材料的组成 .Ni/La0 9Sr0 1Ga0 8Mg0 2 O3 界面上发生的主反应是二甲醚的部分氧化 ,且存在有严重的积碳现象 .电极中掺入SDC( 15 %Sm3 + 掺杂的CeO2 )后 ,二甲醚完全氧化性能明显增强 ;随着电流的增大 ,氢的生成速率显著减小 ,并生成大量的H2 O .采用掺钴镓酸镧基电解质后 ,Ni SDC主要表现为催化二甲醚部分氧化反应 ,且显著抑制了积碳的发生 .Ni SDC/La0 8Sr0 2Ga0 8 Mg0 11Co0 0 9O3 上二甲醚电催化氧化反应的主要产物为 1∶1的CO和H2 .掺钴电解质引起Ni SDC具有特殊的催化性能 ,可能与电解质中

关键词：二甲醚氧化电催化固体氧化物燃料电池阳极镍

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利用钐掺杂氧化铈提高燃料电池阳极活性

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物理化学学报 2003年第9期19卷 844-848页

作者：王世忠 Ishihara tatsumi 厦门大学化学系厦门361005 Department of Applied Chemistry Oita UniversityDannoharu 700Oita 870-1192Japan

用浸渍法制备并采用交流阻抗、极化等技术考察了不同组成的Ni-Sm^(3+)掺杂的CeO_2(SDC)复合镍阳极的电化学性能及相应电池的功率输出性能.结果表明,SDC掺入镍阳极后,阳极极化过电位及电池的欧姆电阻显著减小.其中阳极过电位的减小与SDC... 详细信息

用浸渍法制备并采用交流阻抗、极化等技术考察了不同组成的Ni-Sm^(3+)掺杂的CeO_2(SDC)复合镍阳极的电化学性能及相应电池的功率输出性能.结果表明,SDC掺入镍阳极后,阳极极化过电位及电池的欧姆电阻显著减小.其中阳极过电位的减小与SDC掺入镍电极引起的三相界扩展有关,但SDC的掺入同时引起了电极反应活化能的增加,造成低温下Ni-SDC的极化过电位大于纯Ni电极.高温下,Ni-SDC阳极的阻抗谱由两个半圆组成,其中高频半圆随着SDC掺入量的增加而减小,而低频环与SDC的掺入量基本无关.低温下只观察到一个高频环.高频环可能对应三相界反应,而低频环可能对应氢的解离吸附及扩散.75％(w)Ni-25％(w)SDC/La_(0.9)Sr_(0.1)Ga_(0.8)Mg_(0.2)O_3(LSGM)/Sm_(0.5)Sr_(0.5)CoO_3(SSC)在所研究的电池中具有最大功率输出密度,其值在1073、973、873 K下分别达到1.1、0.43、0.14 W·cm^(-2).

关键词：钐掺杂氧化铈燃料电池阳极活性电化学交流阻抗镍阳极

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利用钐掺杂的氧化铈夹层提高燃料电池阳极的活性

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物理化学学报 2003年第9期19卷 849-853页

作者：王世忠 Ishihara tatsumi 厦门大学化学系厦门361005 Department of Applied Chemistry Oita UniversityDannoharu 700Oita 870-1192Japan

考察了Ni-钐掺杂的氧化铈(Ni-SDC)复合阳极与La_(0.9)Sr_(0.1)Ga_(0.8)Mg_(0.2)O_3(LSGM)电解质中间加入的SDC中间层对阳极及整个电池性能的影响.结果表明,SDC中间层的加入显著减小了阳极极化过电位,但同时引入了欧姆降,降低了电池的功... 详细信息

考察了Ni-钐掺杂的氧化铈(Ni-SDC)复合阳极与La_(0.9)Sr_(0.1)Ga_(0.8)Mg_(0.2)O_3(LSGM)电解质中间加入的SDC中间层对阳极及整个电池性能的影响.结果表明,SDC中间层的加入显著减小了阳极极化过电位,但同时引入了欧姆降,降低了电池的功率输出密度.氢在Ni-SDC电极的氧化主要由两个过程控制,分别对应于交流阻抗谱的两个阻抗半圆,高频环随着SDC中间层的加入显著减小,可能对应于H_2在Ni-SDC/SDC/H_2三相界的电化学氧化或氧从LSGM向SDC的传输,低频环与SDC中间层无关,可能对应于氢在电极表面的解离吸附及吸附物种的扩散过程.使用Ni-SDC/SDC夹层阳极可以明显地提高电池的稳定性.

关键词：钐掺杂氧化铈燃料电池阳极活性镍电极双层阳极极化交流阻抗固体氧化物

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Examination of in vivo mutagenicity of sodium arsenite and dimethylarsinic acid in gpt delta rats

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Journal of Environmental Sciences 2016年第11期28卷 125-130页

作者： Masaki Fujioka Min Gi Satoko Kawachi Kumiko tatsumi Naomi Ishii Kenichiro Doi Anna Kakehashi Hideki Wanibuchi Department of Molecular Pathology Osaka City University Graduate School of Medicine

Arsenic is a well-known human bladder and liver carcinogen, but its exact mechanism of carcinogenicity is not fully understood. Dimethylarsinic acid（DMAV） is a major urinary metabolite of sodium arsenite（i As~Ⅲ） and induces urinary bladder cancers in rats. DMAVand i As~Ⅲare negative in in vitro mutagenicity tests. However, their in vivo mutagenicities have not been determined. The purpose of present study is to evaluate the in vivo mutagenicities of DMAVand i As~Ⅲin rat urinary bladder epithelium and liver using gpt delta F344 ***-week old male gpt delta F344 rats were randomized into 3 groups and administered 0,92 mg/L DMAV, or 87 mg/L i As~Ⅲ（each 50 mg/L As） for 13 weeks in the drinking water. In the mutation assay, point mutations are detected in the gpt gene by 6-thioguanine selection（gpt assay） and deletion mutations are identified in the red/gam genes by Spi-selection（Spi-assay）. Results of the gpt and Spi-assays showed that DMAVand i As~Ⅲhad no effects on the mutant frequencies or mutation spectrum in urinary bladder epithelium or liver. These findings indicate that DMAVand i As~Ⅲare not mutagenic in urinary bladder epithelium or liver in rats.

关键词： Dimethylarsinic acid Sodium arsenite In vivo mutagenicity Urinary bladder epithelium gpt delta rat

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Treatment of bleaching wastewater from pulp paper plants in China using enzymes and coagulants

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Journal of Environmental Sciences 1999年第4期11卷 480-484页

作者： ZHANG Tong Shinji Wada Takao Yamagishi Ichikawa Hiroyasu Kenji tatsumi ZHAO Qing-xiang Department of Environmental Engineering East China University of Science and TechnologyShanghai 200237China National Institute of Resources and Environment 16-3OnogawaTsukubaIbaraki 305Japan

The treatment of wastewater from pulp-paper plants in China by horseradish peroxidase was investigated in this study. The effects of horseradish peroxidase and coagulants were discussed in detail. The results indicated that enzymes might improve the removal of AOX, TOC and colour for pulp\|paper wastewater and modified chitosan is far more effective than Al\-2(SO\-4)\-3 to remove AOX, TOC and colour.

关键词： pulp\|paper wastewater coagulant horseradish peroxidase

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