Osaka, Japan

is a private university in Daitō, Osaka, Japan. The predecessor of the school was founded in 1928, and it was chartered as a junior college in 1950. It became a four-year college in 1965. Osaka Sangyo University operated a satellite campus in Studio City, based on the former campus of Corvallis High School from 1987-2011. It is now occupied by Bridges Academy, which leased the upper upper level from 2005-2011 until it was bought out in early 2011. Wikipedia.

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News Article | December 6, 2016

Researchers using the Atacama Large Millimeter/submillimeter Array (ALMA) have, for the first time, achieved a precise size measurement of small dust particles around a young star through radio-wave polarization. ALMA's high sensitivity for detecting polarized radio waves made possible this important step in tracing the formation of planets around young stars. Astronomers have believed that planets are formed from gas and dust particles, although the details of the process have been veiled. One of the major enigmas is how dust particles as small as 1 micrometer aggregate to form a rocky planet with a diameter of 10 thousand kilometers. Difficulty in measuring the size of dust particles has prevented astronomers from tracing the process of dust growth. Akimasa Kataoka, a Humboldt Research Fellow stationed at Heidelberg University and the National Astronomical Observatory of Japan, tackled this problem. He and his collaborators have theoretically predicted that, around a young star, radio waves scattered by the dust particles should carry unique polarization features. He also noticed that the intensity of polarized emissions allows us to estimate the size of dust particles far better than other methods. To test their prediction, the team led by Kataoka observed the young star HD 142527 with ALMA and discovered, for the first time, the unique polarization pattern in the dust disk around the star. As predicted, the polarization has a radial direction in most parts of the disk, but at the edge of the disk, the direction is flipped perpendicular to the radial direction. Comparing the observed intensity of the polarized emissions with the theoretical prediction, they determined that the size of the dust particles is at most 150 micrometers. This is the first estimation of the dust size based on polarization. Surprisingly, this estimated size is more than 10 times smaller than previously thought. "In the previous studies, astronomers have estimated the size based on radio emissions assuming hypothetical spherical dust particles," explains Kataoka. "In our study, we observed the scattered radio waves through polarization, which carries independent information from the thermal dust emission. Such a big difference in the estimated size of dust particles implies that the previous assumption might be wrong." The team's idea to solve this inconsistency is to consider fluffy, complex-shaped dust particles, not simple spherical dust. In the macroscopic view, such particles are indeed large, but in the microscopic view, each small part of a large dust particle scatters radio waves and produces unique polarization features. According to the present study, astronomers obtain these "microscopic" features through polarization observations. This idea might prompt astronomers to reconsider the previous interpretation of observational data. "The polarization fraction of radio waves from the dust disk around HD 142527 is only a few percent. Thanks to ALMA's high sensitivity, we have detected such a tiny signal to derive information about the size and shape of the dust particles," said Kataoka. "This is the very first step in the research on dust evolution with polarimetry, and I believe the future progress will be full of excitement." Reference: "Millimeter Polarization Observation of the Protoplanetary Disk around HD 142527," A. Kataoka et al., 2016 Nov. 10, Astrophysical Journal Letters [, preprint:]. The research team members are Akimasa Kataoka (Humboldt Research Fellowship for Postdoctoral Researchers / Heidelberg University / National Astronomical Observatory of Japan / former Postdoctoral Fellowship for Research Abroad at Japan Society for Promoting Science), Takashi Tsukagoshi (Ibaraki University), Munetake Momose (Ibaraki University), Hiroshi Nagai (National Astronomical Observatory of Japan), Takayuki Muto (Kogakuin University), Cornelis P. Dullemond (Heidelberg University), Adriana Pohl (Heidelberg University / Max Planck Institute for Astronomy), Misato Fukagawa (Nagoya University), Hiroshi Shibai (Osaka University), Tomoyuki Hanawa (Chiba University), Koji Murakawa (Osaka Sangyo University) This research was supported by a Grant-in-Aid from the Japan Society for the Promotion of Science and the Ministry of Education, Culture, Sports, Science and Technology, Japan (No. 23103004, 15K17606, 26800106). The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Organisation for Astronomical Research in the Southern Hemisphere (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI). ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA. Please follow SpaceRef on Twitter and Like us on Facebook.

Sugimura K.,Tohoku University | Omukai K.,Tohoku University | Inoue A.K.,Osaka Sangyo University
Monthly Notices of the Royal Astronomical Society | Year: 2014

It has been proposed that supermassive black holes (SMBHs) are originated from directcollapse black holes (DCBHs) that are formed at z≲10 in the primordial gas in the case where H2 cooling is suppressed by strong external radiation. In thiswork,we study the critical specific intensity Jcrit required for DCBH formation for various radiation spectral shapes by a series of one-zone calculations of a collapsing primordial-gas cloud. We calculate the critical specific intensity at the Lyman-Werner (LW) bands Jcrit LW,21 (in units of 10-21 erg s-1 Hz-1 sr-1 cm-2) for realistic spectra of metal-poor galaxies.We find that Jcrit is not sensitive to the age or metallicity for the constant star formation galaxies with Jcrit LW,21 = 1300-1400, while Jcrit decreases as galaxies become older or more metal-enriched for the instantaneous starburst galaxies. However, for the young (the age < 100 Myr) and/or extremely metal poor (Z < 5 × 10-4 Z) instantaneous starburst galaxies, such dependence is not strong and Jcrit LW,21 = 1000-1400. We also find that Jcrit is solely determined by the ratio between the H- and H2 photodissociation rate coefficients, kH-,pd/kH2,pd, with which we develop a formula to estimate Jcrit for a given spectrum. The higher value of Jcrit for the realistic spectra than those expected in the literature significantly reduces the estimated DCBH number density nDCBH. By extrapolating the result of Dijkstra, Ferrara & Mesinger, we obtain nDCBH ~ 10-10 cMpc-3 at z = 10, which is roughly consistent with the observed number density of high-redshift SMBHs nSMBH ~ 10-9 cMpc-3 at z ~ 6, considering large uncertainties in the estimation. © 2014 The Authors.

Inoue A.K.,Osaka Sangyo University
Monthly Notices of the Royal Astronomical Society | Year: 2010

It is essential to know galactic emissivity and spectrum of Lyman continuum (LyC) in order to understand the cosmic re-ionization. Here we consider an escape of nebular LyC from galaxies and examine the consequent spectral energy distribution. It is usually assumed that hydrogen nebular LyC mostly produced by bound-free transitions is consumed within photoionized nebulae (so-called on-the-spot approximation). However, an escape of the continuum should be taken into account if stellar LyC escapes from galaxies through 'matter-bounded' nebulae. We show that the escaping hydrogen bound-free LyC makes a strong bump just below the Lyman limit. Such a galaxy would be observed as a Lyman 'bump' galaxy. This bump results from the radiation energy redistribution of stellar LyC by nebulae. The strength of the bump depends on electron temperature in nebulae, escape fraction of stellar and nebular LyC, hardness of stellar LyC (i.e. metallicity, initial mass function, age and star formation history) and intergalactic medium attenuation. We can use the bump to find very young (∼1 Myr), massive (∼100 M⊙) and extremely metal-poor (or metal-free) stellar populations at z < 4. Because of the bump, 900-to-1500 Å luminosity density ratio (per Hz) becomes maximum (two-three times larger than the stellar intrinsic ratio) when about 40 per cent of the stellar LyC is absorbed by nebulae. The total number of escaping LyC photons increases due to the escape of nebular LyC but does not exceed the stellar intrinsic one. The radiation energy redistribution by nebulae reduces the mean energy of escaping LyC only by ≈10 per cent relative to that of stellar LyC. Therefore, the effect of the escape of nebular LyC on the re-ionization process may be small. © 2009 RAS.

Thermodynamic parameter Γ and thermodynamic scaling parameter γ for low-frequency relaxation time, which characterize flip-flop motion in a nematic phase, were verified by molecular dynamics simulation with a simple potential based on the Maier-Saupe theory. The parameter Γ, which is the slope of the logarithm for temperature and volume, was evaluated under various conditions at a wide range of temperatures, pressures, and volumes. To simulate thermodynamic scaling so that experimental data at isobaric, isothermal, and isochoric conditions can be rescaled onto a master curve with the parameters for some liquid crystal (LC) compounds, the relaxation time was evaluated from the first-rank orientational correlation function in the simulations, and thermodynamic scaling was verified with the simple potential representing small clusters. A possibility of an equivalence relationship between Γ and γ determined from the relaxation time in the simulation was assessed with available data from the experiments and simulations. In addition, an argument was proposed for the discrepancy between Γ and γ for some LCs in experiments: the discrepancy arises from disagreement of the value of the order parameter P2 rather than the constancy of relaxation time τ 1* on pressure. © 2013 American Institute of Physics.

Horikoshi R.,Osaka Sangyo University
Journal of Chemical Education | Year: 2015

A unique method has been developed using an interlocking building-block model equipped with magnets to illustrate the catalytic asymmetric hydrogenation of Î′-keto esters by a BINAP-ruthenium complex to enhance students' understanding of this process. A BINAP-ruthenium block model, mimicking the coordination environment around the metal center in the real complex, can be used to convert the Î′-keto ester model into a Î′-hydroxy ester model. This model was used to provide a greater understanding of the essence of the catalytic reaction and to assist students in their understanding of its mechanism. © 2014 The American Chemical Society and Division of Chemical Education, Inc.

Zackrisson E.,The Oskar Klein Center | Inoue A.K.,Osaka Sangyo University | Jensen H.,The Oskar Klein Center
Astrophysical Journal | Year: 2013

The fraction of ionizing photons that escape (f esc) from z ≳ 6 galaxies is an important parameter for assessing the role of these objects in the reionization of the universe, but the opacity of the intergalactic medium precludes a direct measurement of f esc for individual galaxies at these epochs. We argue that since f esc regulates the impact of nebular emission on the spectra of galaxies, it should nonetheless be possible to indirectly probe f esc well into the reionization epoch. As a first step, we demonstrate that by combining measurements of the rest-frame UV slope β with the equivalent width of the Hβ emission line, galaxies with very high Lyman continuum escape fractions (f esc ≥ 0.5) should be identifiable up to z = 9 through spectroscopy with the upcoming James Webb Space Telescope (JWST). By targeting strongly lensed galaxies behind low-redshift galaxy clusters, JWST spectra of sufficiently good quality can be obtained for M 1500 ≲ -16.0 galaxies at z = 7 and for M 1500 ≲ -17.5 galaxies at z = 9. Dust-obscured star formation may complicate the analysis, but supporting observations with ALMA or the planned SPICA mission may provide useful constraints on this effect. © 2013. The American Astronomical Society. All rights reserved.

Inoue A.K.,Osaka Sangyo University
Earth, Planets and Space | Year: 2011

The origin of cosmic dust is a fundamental issue in planetary science. This paper revisits the origin of dust in galaxies, in particular, in the Milky Way, by using a chemical evolution model of a galaxy composed of stars, interstellar medium, metals (elements heavier than helium), and dust. We start from a review of timeevolutionary equations of the four components, and then, we present simple recipes for the stellar remnant mass and yields of metal and dust based on models of stellar nucleosynthesis and dust formation. After calibrating some model parameters with the data from the solar neighborhood, we have confirmed a shortage of the stellardust-production rate relative to the dust-destruction rate by supernovae if the destruction efficiency suggested by theoretical works is correct. If the dust-mass growth by material accretion in molecular clouds is active, the observed dust amount in the solar neighborhood is reproduced. We present a clear analytic explanation of the mechanism for determining dust content in galaxies after the activation of accretion growth: a balance between accretion growth and supernova destruction. Thus, the dust content is independent of the uncertainty of the stellar dust yield after the growth activation. The timing of the activation is determined by a critical metal mass fraction which depends on the growth and destruction efficiencies. The solar system formation seems to have occurred well after the activation and plenty of dust would have existed in the proto-solar nebula. Copyright © The Society of Geomagnetism and Earth Planetary and Space Sciences (SGEPSS).

Inoue H.,Osaka Sangyo University
Physica A: Statistical Mechanics and its Applications | Year: 2014

Companies are exposed to rigid competition, so they seek how best to improve the capabilities of their innovations. One strategy is to collaborate with other companies in order to speed up their own innovations. Such inter-company collaborations are conducted by inventors belonging to the companies. At the same time, the inventors also seem to be affected by past collaborations between companies. Therefore, interdependency of two networks, namely inventor and company networks, exists. This paper discusses a model that replicates two-layer networks extracted from patent data of Japan and the United States in terms of degree distributions. The model replicates two-layer networks with the interdependency. Moreover it is the only model that uses local information, while other models have to use overall information, which is unrealistic. In addition, the proposed model replicates empirical data better than other models. © 2014 The Author. Published by Elsevier B.V. This is an open access article under the CC.

Inoue A.K.,Osaka Sangyo University
Monthly Notices of the Royal Astronomical Society | Year: 2011

Finding the first generation of galaxies in the early Universe is the greatest step forward towards understanding galaxy formation and evolution. For a strategic survey of such galaxies and the interpretation of the obtained data, this paper presents an ultraviolet-to-optical spectral model of galaxies with a great care of the nebular emission. In particular, we present a machine-readable table of intensities of 119 nebular emission lines from Lyα to the rest-frame 1m as a function of metallicity from zero to the solar one. Based on the spectral model, we present criteria of equivalent widths of Lyα, Heiiλ1640, Hα, Hβ and [Oiii]λ5007 to select extremely metal-poor and metal-free galaxies although these criteria have uncertainty caused by the Lyman continuum escape fraction and the star formation duration. We also present criteria of broad-band colours which will be useful to select candidates for spectroscopic follow-up from drop-out galaxies. We propose the line intensity ratio of [Oiii]λ5007 to Hβ <0.1 as the most robust criterion for <1/1000 of the solar metallicity. This ratio of a galaxy with a few M⊙yr-1 at z∼ 8 is detectable by spectroscopy with the James Webb Space Telescope within a reasonable exposure time. © 2011 The Author Monthly Notices of the Royal Astronomical Society © 2011 RAS.

Purpose: Sagittal gap balancing (relation between flexion and extension gaps) with placement of trial femoral components and reduction of the patella in total knee arthroplasty (TKA) is important, but it is not easy. The purpose of this study was to investigate whether (1) the flexion and extension gaps were equal when a previously suggested three-dimensional planning for a single-radius femoral component (its sagittal centre is matched with flexion-extension axis of knee movement) is executed with patient-specific instrumentation (PSI) and whether (2) PSI was done with good accuracy, which did not affect the first purpose.Methods: Posterior cruciate ligament sacrificed (PS) TKA was performed on 12 joints. Using the patients’ pre-operative computed tomography (CT) images, PSI was manufactured to fit on the bony surface of the knee joint and to simultaneously transfer pre-operative planning to the operating room. After osteotomy with PSI, gap measurements were calculated with the knee in flexion and extension. Angle deviations of both components were investigated with postoperative CT images.Results: The flexion gap (mean, 19.1 mm) was larger than the extension gap (mean, 12.3 mm) in all cases. Angle differences between pre- and postoperative alignments were within 3° in all cases.Conclusions: Although PSI executed the pre-operative planning with good accuracy, the flexion gap is always larger than the extension gap. This finding suggests that surgeons may not aim for equal gaps of flexion and extension in PS-TKA. © 2014, SICOT aisbl.

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