Institution
Tohoku University
Education•Sendai, Japan•
About: Tohoku University is a education organization based out in Sendai, Japan. It is known for research contribution in the topics: Magnetization & Alloy. The organization has 72116 authors who have published 170791 publications receiving 3941714 citations. The organization is also known as: Tōhoku daigaku.
Topics: Magnetization, Alloy, Catalysis, Population, Magnetic field
Papers published on a yearly basis
Papers
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TL;DR: In this paper, the authors describe observations carried out by the MOA group of the Galactic bulge during 2000 that were designed to detect efficiently gravitational microlensing of faint stars in which the magnification is high and/or of short duration.
Abstract: We describe observations carried out by the MOA group of the Galactic bulge during 2000 that were designed to detect efficiently gravitational microlensing of faint stars in which the magnification is high and/or of short duration. These events are particularly useful for studies of extrasolar planets and faint stars. Approximately 17 deg2 were monitored at a sampling rate of up to six times per night. The images were analysed in real time using a difference imaging technique. 20 microlensing candidates were detected, of which eight were alerted to the microlensing community whilst in progress. Approximately half of the candidates had high magnifications (≳10), at least one had very high magnification (≳50), and one exhibited a clear parallax effect. The details of these events are reported here, together with details of the on-line difference imaging technique. Some nova-like events were also observed and these are described, together with one asteroid.
505 citations
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TL;DR: In this article, it was shown that the observed spectrum can be understood within a stripe model by taking account of quantum excitations, which supports the concept that stripe correlations are essential to high-transition-temperature superconductivity.
Abstract: In the copper oxide parent compounds of the high-transition-temperature superconductors the valence electrons are localized--one per copper site--by strong intra-atomic Coulomb repulsion. A symptom of this localization is antiferromagnetism, where the spins of localized electrons alternate between up and down. Superconductivity appears when mobile 'holes' are doped into this insulating state, and it coexists with antiferromagnetic fluctuations. In one approach to describing the coexistence, the holes are believed to self-organize into 'stripes' that alternate with antiferromagnetic (insulating) regions within copper oxide planes, which would necessitate an unconventional mechanism of superconductivity. There is an apparent problem with this picture, however: measurements of magnetic excitations in superconducting YBa2Cu3O6+x near optimum doping are incompatible with the naive expectations for a material with stripes. Here we report neutron scattering measurements on stripe-ordered La1.875Ba0.125CuO4. We show that the measured excitations are, surprisingly, quite similar to those in YBa2Cu3O6+x (refs 9, 10) (that is, the predicted spectrum of magnetic excitations is wrong). We find instead that the observed spectrum can be understood within a stripe model by taking account of quantum excitations. Our results support the concept that stripe correlations are essential to high-transition-temperature superconductivity.
505 citations
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University of Rhode Island1, Stockholm University2, Utrecht University3, Brown University4, United States Geological Survey5, Rice University6, University of Bordeaux7, Centre national de la recherche scientifique8, Yamagata University9, University College London10, Norwegian Polar Institute11, Boston University12, British Geological Survey13, University of Michigan14, Kyushu University15, National Oceanography Centre16, University of Aberdeen17, University of Padua18, Japan Agency for Marine-Earth Science and Technology19, James Madison University20, Nagoya University21, Tohoku University22, Hokkaido University23, Leibniz Institute of Marine Sciences24, Paul Scherrer Institute25, University of Bergen26
TL;DR: This record of the Neogene reveals cooling of the Arctic that was synchronous with the expansion of Greenland ice and East Antarctic ice and supporting arguments for bipolar symmetry in climate change.
Abstract: The history of the Arctic Ocean during the Cenozoic era (0–65 million years ago) is largely unknown from direct evidence. Here we present a Cenozoic palaeoceanographic record constructed from >400 m of sediment core from a recent drilling expedition to the Lomonosov ridge in the Arctic Ocean. Our record shows a palaeoenvironmental transition from a warm ‘greenhouse’ world, during the late Palaeocene and early Eocene epochs, to a colder ‘icehouse’ world influenced by sea ice and icebergs from the middle Eocene epoch to the present. For the most recent ~14 Myr, we find sedimentation rates of 1–2 cm per thousand years, in stark contrast to the substantially lower rates proposed in earlier studies; this record of the Neogene reveals cooling of the Arctic that was synchronous with the expansion of Greenland ice (~3.2 Myr ago) and East Antarctic ice (~14 Myr ago). We find evidence for the first occurrence of ice-rafted debris in the middle Eocene epoch (~45 Myr ago), some 35 Myr earlier than previously thought; fresh surface waters were present at ~49 Myr ago, before the onset of ice-rafted debris. Also, the temperatures of surface waters during the Palaeocene/Eocene thermal maximum (~55 Myr ago) appear to have been substantially warmer than previously estimated. The revised timing of the earliest Arctic cooling events coincides with those from Antarctica, supporting arguments for bipolar symmetry in climate change.
505 citations
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TL;DR: This is the first demonstration that oxytocin may regulate serotonin release and exert anxiolytic effects via direct activation of Oxytocin receptor expressed in serotonergic neurons of the raphe nuclei.
Abstract: The oxytocin receptor has been implicated in the regulation of reproductive physiology as well as social and emotional behaviors. The neurochemical mechanisms by which oxytocin receptor modulates social and emotional behavior remains elusive, in part because of a lack of sensitive and selective antibodies for cellular localization. To more precisely characterize oxytocin receptor-expressing neurons within the brain, we generated an oxytocin receptor-reporter mouse in which part of the oxytocin receptor gene was replaced with Venus cDNA (a variant of yellow fluorescent protein). Examination of the Venus expression revealed that, in the raphe nuclei, about one-half of tryptophan hydroxylase-immunoreactive neurons were positive for Venus, suggesting a potential role for oxytocin in the modulation of serotonin release. Oxytocin infusion facilitated serotonin release within the median raphe nucleus and reduced anxiety-related behavior. Infusion of a 5-HT 2A/2C receptor antagonist blocked the anxiolytic effect of oxytocin, suggesting that oxytocin receptor activation in serotonergic neurons mediates the anxiolytic effects of oxytocin. This is the first demonstration that oxytocin may regulate serotonin release and exert anxiolytic effects via direct activation of oxytocin receptor expressed in serotonergic neurons of the raphe nuclei. These results also have important implications for psychiatric disorders such as autism and depression in which both the oxytocin and serotonin systems have been implicated.
504 citations
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TL;DR: It is shown that heme binds specifically to Bach1 and regulates its DNA‐binding activity, suggesting that increased levels of heme inactivate the repressor Bach1, resulting in induction of a host of genes with MAREs.
Abstract: Heme controls expression of genes involved in the synthesis of globins and heme. The mammalian transcription factor Bach1 functions as a repressor of the Maf recognition element (MARE) by forming antagonizing hetero-oligomers with the small Maf family proteins. We show here that heme binds specifically to Bach1 and regulates its DNA-binding activity. Deletion studies demonstrated that a heme-binding region of Bach1 is confined within its C-terminal region that possesses four dipeptide cysteine–proline (CP) motifs. Mutations in all of the CP motifs of Bach1 abolished its interaction with heme. The DNA-binding activity of Bach1 as a MafK hetero-oligomer was markedly inhibited by heme in gel mobility shift assays. The repressor activity of Bach1 was lost upon addition of hemin in transfected cells. These results suggest that increased levels of heme inactivate the repressor Bach1, resulting in induction of a host of genes with MAREs.
501 citations
Authors
Showing all 72477 results
Name | H-index | Papers | Citations |
---|---|---|---|
John Q. Trojanowski | 226 | 1467 | 213948 |
Aaron R. Folsom | 181 | 1118 | 134044 |
Marc G. Caron | 173 | 674 | 99802 |
Masayuki Yamamoto | 171 | 1576 | 123028 |
Kenji Watanabe | 167 | 2359 | 129337 |
Rodney S. Ruoff | 164 | 666 | 194902 |
Frederik Barkhof | 154 | 1449 | 104982 |
Takashi Taniguchi | 152 | 2141 | 110658 |
Yoshio Bando | 147 | 1234 | 80883 |
Thomas P. Russell | 141 | 1012 | 80055 |
Ali Khademhosseini | 140 | 887 | 76430 |
Marco Colonna | 139 | 512 | 71166 |
David H. Barlow | 133 | 786 | 72730 |
Lin Gu | 130 | 868 | 56157 |
Yoichiro Iwakura | 129 | 705 | 64041 |