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Imaging characteristics of hypervascular focal nodular hyperplasialike lesions in patients with chronic alcoholic liver disease

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World Journal of Gastroenterology 2025年第2期31卷 61-70页

作者： atsushi Urase Masakatsu Tsurusaki Ryohei Kozuki atsushi Kono Keitaro Sofue Kazunari Ishii Department of Radiology Kindai UniversityFaculty of MedicineOsakasayama 589-8511OsakaJapan Department of Radiology Kansai Medical University Medical CenterMoriguchi 570-8507OsakaJapan Department of Radiology Kobe University Graduate School of MedicineKobe 650-0017HyogoJapan

BACKGROUND Focal nodular hyperplasia(FNH)-like lesions are hyperplastic formations in patients with micronodular cirrhosis and a history of alcohol *** pathologically similar to hepatocellular carcinoma(HCC)lesions,they are *** such,it is important to develop methods to distinguish between FNH-like lesions and *** To evaluate diagnostically differential radiological findings between FNH-like lesions and *** We studied pathologically confirmed FNH-like lesions in 13 patients with alco-holic cirrhosis[10 men and 3 women;mean age:54.5±12.5(33-72)years]who were negative for hepatitis-B surface antigen and hepatitis-C virus antibody and underwent dynamic computed tomography(CT)and magnetic resonance imaging(MRI),including superparamagnetic iron oxide(SPIO)and/or gadoxetic acid-enhanced *** patients also underwent angiography-assisted *** The evaluated lesion features included arterial enhancement pattern,washout appearance(low density compared with that of surrounding liver parenchyma),signal intensity on T1-weighted image(T1WI)and T2-weighted image(T2WI),central scar presence,chemical shift on in-and out-of-phase images,and uptake pattern on gadoxetic acid-enhanced MRI hepatobiliary phase and SPIO-enhanced *** patients had multiple small lesions(<1.5 cm).Radiological features of FNH-like lesions included hypervascularity despite small lesions,lack of“corona-like”enhancement in the late phase on CT during hepatic angiography(CTHA),high-intensity on T1WI,slightly high-or iso-intensity on T2WI,no signal decrease in out-of-phase images,and complete SPIO uptake or incomplete/partial uptake of gadoxetic ***,similar to HCC,FNH-like lesions showed many unpaired arteries and sinusoidal *** Overall,the present study showed that FNH-like lesions have unique radiological findings useful for differential ***,SPIO-and/or gadoxetic acid-enhanced MRI and CTHA features might facili

关键词： Focal nodular hyperplasia Alcoholic liver disease Hepatocellular carcinoma Magnetic resonance imaging Liver

MUON-CATALYZED FUSION AND MUONIC MOLECULES

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原子与分子物理学报 1990年第4期7卷 1623-1627页

作者： Isao shimamura RIKEN HirosawaWakoSaitama 351-01Japan

The d-t and d-d fusion catalyzed by muons without the need of high-temperature plasmas has been the subject of increasing experimental and theor-etical interest in these *** has been established experimentally that a singlemuon can catalyze d-t fusion about 150 times on the average during its lifetimein a dense mixture of deuterium and tritium under certain *** pure deuterium without tritium less efficlent muon-catalyzed d-d fusionoccurs.

关键词： M介子催化聚变 M分子

Transformations of the Pleiomorphic Plant MTOC during Sporogenesis in the Hepatic Marchantia polymorpha

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Journal of Integrative Plant Biology 2007年第8期49卷 1244-1252页

作者： Roy C.Brown Betty E.Lemmon Masaki shimamura Department of Biology University of Louisiana-LafayetteLafayetteLA 70504USA Department of Biological ScienceGraduate School of ScienceHiroshima UniversityKagami-yamaHigashi-Hiroshima 739-8526Japan

Sporogenesis in the hepatic Marchantia polymorpha L. provides an outstanding example of the pleiomorphic nature of the plant microtubule organizing center （MTOC）. Microtubules are nucleated from γ-tubuUn in MTOCs that change form during mitosis and meiosis. Following entry of cells into the reproductive pathway of sporogenesis, successive rounds of mitosis give rise to packets of 4-16 sporocytes. Mitotic spindles are organized at discrete polar organizers （POs）, a type of MTOC that is unique to this group of early divergent land plants. An abrupt and radical transformation in microtubule organization occurs when sporocytes enter meiosis： POs are lost and γ-tubulin is closely associated with surfaces of two large elongated plastids that subsequently divide into four. Migration of the four plastid MTOCs into a tetrahedral arrangement establishes the future spore domains and the division polarity of meiosis. As is typical of many bryophytes, cones of microtubules from the four plastid MTOCs initiate a quadripolar microtubule system （QMS） in meiotic prophase. At this point a transformation in the organization of the MTOCs occurs. The γ-tubulin detaches from plastids and forms a diffuse spheroidal pole in each of the spore domains. The plastids, which are no longer MTOCs, continue to divide. The diffuse MTOCs continue to nucleate cones of microtubules during transformation of the QMS to a bipolar spindle. Following meiosis I, γ-tubulin is associated with nuclear envelopes, and the spindles of meiosis II are organized from diffuse MTOCs at the tetrad poles. At simultaneous cytokinesis, radial microtubule systems are organized at nuclear envelope MTOCs in each of the tetrad members.

关键词： bryophyte γ-tubulin meiosis microtubules mitosis MTOC.

Ultrafast reorientation of the Néel vector in antiferromagnetic Dirac semimetals

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npj Computational Materials 2021年第1期7卷 1562-1568页

作者： atsushi Ono Sumio Ishihara Department of Physics Tohoku UniversitySendai 980-8578Japan

Antiferromagnets exhibit distinctive characteristics such as ultrafast dynamics and robustness against perturbative fields,thereby attracting considerable interest in fundamental physics and technological ***,it was revealed that the Néel vector can be switched by a current-induced staggered(Néel)spin-orbit torque in antiferromagnets with the parity-time symmetry,and furthermore,a nonsymmorphic symmetry enables the control of Dirac ***,the real-time dynamics of the magnetic and electronic structures remain largely ***,we propose a theory of the ultrafast dynamics in antiferromagnetic Dirac semimetals and show that the Néel vector is rotated in the picosecond timescale by the terahertz-pulse-induced Néel spin-orbit torque and other torques originating from magnetic *** reorientation accompanies the modulation of the mass of Dirac fermions and can be observed in real time by the magneto-optical *** results provide a theoretical basis for emerging ultrafast antiferromagnetic spintronics combined with the topological aspects of materials.

关键词： materials Dirac metals

Accumulation of aberrant DNA methylation during colorectal cancer development

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World Journal of Gastroenterology 2014年第4期20卷 978-987页

作者： Eiji Sakai atsushi Nakajima atsushi Kaneda Department of Gastroenterology Yokohama City University School of Medicine Genome Science Division Research Center for Advanced Science and Technology The University of Tokyo Department of Molecular Oncology Graduate School of Medicine Chiba University CREST Japan Science and Technology Agency

Despite the recent advances in the therapeutic modalities,colorectal cancer(CRC)remains to be one of the most common causes of cancer-related *** arises through accumulation of multiple genetic and epigenetic alterations that transform normal colonic epithelium into *** crucial roles of epigenetic alterations,gene silencing by aberrant DNA methylation of promoter regions is one of the most important epigenetic *** comprehensive methylation analyses on genome-wide scale revealed that sporadic CRC can be classified into distinct *** epigenotype cooperates with specific genetic alterations,suggesting that they represent different molecular carcinogenic *** lesions of CRC,such as conventional and serrated adenomas,already show similar methylation accumulation to CRC,and can therefore be classified into those epigenotypes of *** addition,specific DNA methylation already occurs in the normal colonic mucosa,which might be utilized for prediction of the personal CRC *** methylation is suggested to occur at an earlier stage than carcinoma formation,and may predict the molecular basis for future development of ***,we review DNA methylation and CRC classification,and discuss the possible clinical usefulness of DNA methylation as biomarkers for the diagnosis,prediction of the prognosis and the response to therapy of CRC.

关键词： Colorectal cancer Colorectal adenoma Aberrant crypt foci Genetic mutation Epigenotype DNA methylation Colorectal carcinogenesis

Imbricate structure of the Otakeyama area, Okayama Permian Yoshii Group in the Prefecture, southwest Japan

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Frontiers of Earth Science 2015年第1期9卷 152-163页

作者： Tsuyoshi ITO atsushi MATSUOKA State Key Laboratory of Geo-processes and Mineral Resources China University of Geosciences Wuhan 430074 China Department of Geology Faculty of Science Niigata University Niigata 950-2181 Japan

The Yoshii Group of the Akiyoshi terrane is distributed over the Otakeyama area, Okayama Prefecture, southwest Japan. The Yoshii Group is composed of siliceous rocks and clastics, comprising chert-clastic sequences. The Yoshii Group is divided into four structural units （Units Ot 1, Ot 2, Ot 3, and Ot 4） in structurally ascending order. Lithological similarities and radiolarian age suggest that these units exhibit almost identical ocean plate stratigraphy. These units are structurally-repeated to form an imbricate structure. This structure was possibly formed by off-scrape accretion at a toe of an accretionary complex. Additionally, a review of previous studies indicates that an imbricate structure is common in the Akiyoshi terrane. The presence of an imbricate structure in the Akiyoshi terrane, Permian accretionary complex, indicates the possibility that a specific horizon of Permian pelagic sequences acted as a drcollement zone.

关键词： accretionary complex imbricate structure,Permian radiolafia Yoshii Group Okayama Prefecture,southwest Japan

Balancing timber production and habitat conservation of Okinawa Rails(Gallirallus okinawae): Application of a harvest scheduling optimization model in subtropical forest in Okinawa, Japan

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Journal of Mountain Science 2019年第12期16卷 2770-2782页

作者： KONOSHIMA Masashi YOSHIMOTO atsushi Faculty of Agriculture University of the Ryukyusi SenbaruNishihara ChoOkinawa903-0213 Japan Institute of Statistical Mathematics(ISM) 10-3 Midori-choTachikawaTokyo 190-8562Japan

Finding the right balance between timber production and the management of forest-dependent wildlife species,present a difficult challenge for forest resource managers and policy makers in Okinawa,Japan.A possible explanation of this can be found in the unique nature of the forest management area which is populated with various kinds of rare and endangered *** issue has been brought to light as a result of the nomination of northern Okinawa Island in 2018 as a candidate for World Natural Heritage *** nomination has raised public awareness to the possibility of conflicting management objectives between timber extraction and the conservation of habitat for forest-dependent wildlife *** exclusively for one objective over the other may fail to meet the demand for both forest products and wildlife habitat,ultimately jeopardizing the stability of human and wildlife *** is therefore important to achieve a better balance between the objective of timber production and conservation of wildlife *** the significance of this subject area,current ongoing discussions on how to effectively manage for forest resources,often lack scientific basis to make sound judgement or evaluate tradeoffs between conflicting *** the effect of these forest management activities on wildlife habitat provides useful and important information needed to make forest management and policy *** this study we develop a spatial timber harvest scheduling model that incorporates habitat suitability index(HSI)models for the Okinawa Rail(Gallirallus okinawae),an endangered avian species found on Okinawa,*** illustrate how the proposed coupling model assembles spatial information,which ultimately aids the study of forest management effects on wildlife habitat,we apply these models to a forest area in Okinawa and conduct a simple simulation analysis.

关键词： Harvest scheduling Habitat suitability index model Optimization model Timber production Wildlife habitat

Response of understory vegetation over 10 years after thinning in an old-growth cedar and cypress plantation overgrazed by sika deer in eastern Japan

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Forest Ecosystems 2017年第2期4卷 93-102页

作者： atsushi Tamura Masanobu Yamane Division of Forest Research and Nature Restoration Planning Kanagawa Prefecture Natural Environment Conservation Center 657 Nanasawa AtsugiKanagawa 243-072 Japan

Background： Forest management strategies such as thinning have long been used to enhance ecosystem functions, especially in *** in plantations with high deer density, however, may not yield a desired increase in understory vegetation because deer graze on germinating plants after ***, we examine the changes in understory vegetation after thinning in plantations that have been overgrazed by sika deer to provide insight into the effects of thinning on ecosystem functions such as soil conservation and biological ***： We conducted our survey in the Tanzawa Mountains of eastern *** surveyed the change in understory vegetation within and outside of three deer exclosures on a single slope with three levels of understory vegetation cover： sparse（1%, exclosure ＂US＂）, moderate（30%, exclosure ＂MM＂）, and dense（80%, exclosure ＂LD＂） over10 years after a 30% thinning of an old-growth cedar and cypress plantation which was overgrazed by sika ***： Understory vegetation cover, biomass and species richness increased within and outside the ＂US＂ and＂MM＂ exclosures after thinning, and biomass was greater within than outside the exclosures at 10 years after *** species dominated both ＂US＂ and ＂MM＂ exclosures before thinning, and trees and shrubs dominated within the exclosures over time after *** contrast, unpalatable, grazing-tolerant, perennial,and annual species increased outside the ＂US＂ and ＂MM＂ *** noticeable changes were observed within and outside the ＂LD＂ exclosure when compared with the ＂US＂ and ＂MM＂ ***： Our results suggest that thinning a stand by 30% based on volume resulted in an increase in understory vegetation cover mainly composed of both unpalatable and grazing-tolerant species in a plantation forest where understory vegetation is sparse or moderate and sika deer density is *** emphasize that establishing deer exclosures or controlling deer is essential to ma

关键词： Biomass Deer exclosure Grazing-tolerant species Understory cover Unpalatable species

Numerical investigation into pillar failure induced by time-dependent skin degradation

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International Journal of Mining Science and Technology 2017年第4期27卷 591-597页

作者： Sainoki atsushi Mitri Hani S. Department of Mining and Materials Engineering McGill University Montreal H3A0E8 Canada

This paper focuses on the instability mechanism of an isolated pillar, caused by time-dependent skin degradation and strength heterogeneity. The time-dependent skin degradation is simulated with a non-linear rheological model capable of simulating tertiary creep, whereby two different pillar failure cases are investigated. The first case is of an isolated pillar in a deep hard rock underground mine and subjected to high stresses. The results show that pillar degradation is limited to the regions near the surface or the skin until two months after ore extraction. Afterwards degradation starts to extend deeper into the pillar, eventually leaving a highly-stressed pillar core due to stress transfer from the failed *** potential indices show that the risk increases exponentially at the core as time goes by. It is then demonstrated that the progressive skin degradation cannot be simulated with conventional strain-softening model assuming brittle failure. The parametric study with respect to the degree of heterogeneity reveals that heterogeneity is key to the occurrence of progressive skin degradation. The second case investigated in this study is pillar failure taking place in a very long period. Such failure becomes significantly important when assessing the risk for ground subsidence caused by pillar collapse in an abandoned mine. The analysis results demonstrate that the employed non-linear rheological model can simulate gradual skin degradation taking place over several hundred years. The percentage of damage zone volume within the pillar is merely 1% after a lapse of one days and increases to 50% after one hundred years, indicating a high risk for pillar collapse in the long term. The vertical displacements within the pillar also indicate the risk of subsidence. The proposed method is suitable for evaluating the risk of ground surface subsidence above an abandoned mine.

关键词： Pillar stability Underground mine Skin degradation Rheological model Time-dependent failure