ADVANTAGES OF THE AKARI FIR ALL-SKY MAPS

YASUO DOI,SATOSHI TAKITA,TAKAFUMI OOTSUBO,KO ARIMATSU,MASAHIRO TANAKA,TAKAHIRO MORISHIMA,MITSUNOBU KAWADA,SHUJI MATSUURA,YOSHIMI KITAMURA,MAKOTO HATTORI,TAKAO NAKAGAWA,GLENN WHITE,NORIO IKEDA 한국천문학회 2017 天文學論叢 Vol.32 No.1

We present the {\it AKARI} far-infrared (FIR) all-sky maps and describe its characteristics, calibration accuracy and scientific capabilities. The {\it AKARI} FIR survey has covered 97\% of the whole sky in four photometric bands, which cover continuously 50--180 micron with band central wavelengths of 65, 90, 140, and 160 microns. The data have been publicly released in 2014 \citep{2015PASJ...67...50D} with improved data quality that have been achieved since the last internal data release \citep{2012PKAS...27..111D}. The accuracy of the absolute intensity is $\leq10$\% for the brighter regions. Quantitative analysis of the relative intensity accuracy and its dependence upon spatial scan numbers has been carried out. The data for the first time reveal the whole sky distribution ofinterstellar matter with arcminute-scale spatial resolutions at the peakof dust continuum emission, enabling us to investigate large-scaledistribution of interstellar medium in great detail. The filamentarystructure covering the whole sky is well traced by the all-sky maps. We describe advantages of the AKARI FIR all-sky maps for the study of interstellar matter comparing to other observational data.

AKARI FAR-INFRARED ALL-SKY SURVEY MAPS

Doi, Yasuo,Komugi, Shinya,Kawada, Mitsunobu,Takita, Satoshi,Arimatsu, Ko,Ikeda, Norio,Kato, Daisuke,Kitamura, Yoshimi,Nakagawa, Takao,Ootsubo, Takafumi,Morishima, Takahiro,Hattori, Makoto,Tanaka, Masa The Korean Astronomical Society 2012 天文學論叢 Vol.27 No.4

Far-infrared observations provide crucial data for the investigation and characterisation of the properties of dusty material in the Interstellar Medium (ISM), since most of its energy is emitted between ~ 100 and $200{\mu}m$. We present the first all-sky image from a sensitive all-sky survey using the Japanese AKARI satellite, in the wavelength range $50-180{\mu}m$. Covering > 99% of the sky in four photometric bands with four filters centred at $65{\mu}m$, $90{\mu}m$, $140{\mu}m$, and $160{\mu}m$ wavelengths, this achieved spatial resolutions from 1 to 2 arcmin and a detection limit of < 10 MJy $sr^{-1}$, with absolute and relative photometric accuracies of < 20%. All-sky images of the Galactic dust continuum emission enable astronomers to map the large-scale distribution of the diffuse ISM cirrus, to study its thermal dust temperature, emissivity and column density, and to measure the interaction of the Galactic radiation field and embedded objects with the surrounding ISM. In addition to the point source population of stars, protostars, star-forming regions, and galaxies, the high Galactic latitude sky is shown to be covered with a diffuse filamentary-web of dusty emission that traces the potential sites of high latitude star formation. We show that the temperature of dust particles in thermal equilibrium with the ambient interstellar radiation field can be estimated by using $90{\mu}m$, $140{\mu}m$, and $160{\mu}m$ data. The FIR AKARI full-sky maps provide a rich new data set within which astronomers can investigate the distribution of interstellar matter throughout our Galaxy, and beyond.

THE FILAMENTARY WEB OF STAR FORMATION

White, Glenn J.,Doi, Yasuo,Komugi, Shinya,Kawada, Mitsunobu,Takita, Satoshi,Arimatsu, Ko,Ikeda, Norio,Kato, Daisuke,Kitamura, Yoshimi,Nakagawa, Takao,Ootsubo, Takafumi,Morishima, Takahiro,Hattori, Mak The Korean Astronomical Society 2012 天文學論叢 Vol.27 No.4

Following the first Public Release of the AKARI Point Source catalogues, we have worked on the production of a new far-infrared All-Sky Diffuse mapping product. In this paper we report first results from the All Sky diffuse maps that will shortly be released to the community, based on analysis of data from the Far Infrared Surveyor ($65{\mu}m-160{\mu}m$) instrument. These data are likely to have a strong impact on studies of extended structures, and the diffuse ISM.

Cellular Density Evaluation for Malignant Lymphoma Using Equivalent Cross-Relaxation Rate Imaging - Initial Experience

Hideyuki Nishiofuku,Shigeru Matsushima,Yoshitaka Inaba,Hidekazu Yamaura,Yozo Sato,Yasuo Morishima,Kimihiko Kichikawa 대한영상의학회 2010 Korean Journal of Radiology Vol.11 No.3

Objective: Equivalent cross-relaxation rate (ECR) imaging is an MRI technique used to evaluate quantitatively a change in the protein-water interaction. We aimed to evaluate retrospectively the usefulness of ECR imaging for the histologic classification of malignant lymphoma (ML). Materials and Methods: Institutional Review Board approval was obtained and all patients provided informed consent. The study subjects included 15 patients with untreated ML who were histologically diagnosed with follicular lymphoma (FL; n = 8) or diffuse large B-cell lymphoma (DLBCL; n = 7). All patients underwent ECR imaging and the offset frequency was set at 7 ppm. Results: The median ECR values were 71% (range; 60.7 to 75.5) in FL and 54% (50.8 to 59.4) in DLBCL (p = 0.001). The median cellular density was 1.5 0.17 × 106 / mm2 in FL and 1.0 ± 0.70 × 106 / mm2 in DLBCL (p = 0.001). The correlation coefficient between the ECR values and cellular density in ML was 0.88 (p = 0.001). In FL and DLBCL, assuming ECR value cut-off points of 60%, both sensitivity and specificity were 100%. Conclusion: A strong correlation between ECR and cellular density in ML is demonstrated and the ECR may be a useful technique to differentiate between FL and DLBCL. Objective: Equivalent cross-relaxation rate (ECR) imaging is an MRI technique used to evaluate quantitatively a change in the protein-water interaction. We aimed to evaluate retrospectively the usefulness of ECR imaging for the histologic classification of malignant lymphoma (ML). Materials and Methods: Institutional Review Board approval was obtained and all patients provided informed consent. The study subjects included 15 patients with untreated ML who were histologically diagnosed with follicular lymphoma (FL; n = 8) or diffuse large B-cell lymphoma (DLBCL; n = 7). All patients underwent ECR imaging and the offset frequency was set at 7 ppm. Results: The median ECR values were 71% (range; 60.7 to 75.5) in FL and 54% (50.8 to 59.4) in DLBCL (p = 0.001). The median cellular density was 1.5 0.17 × 106 / mm2 in FL and 1.0 ± 0.70 × 106 / mm2 in DLBCL (p = 0.001). The correlation coefficient between the ECR values and cellular density in ML was 0.88 (p = 0.001). In FL and DLBCL, assuming ECR value cut-off points of 60%, both sensitivity and specificity were 100%. Conclusion: A strong correlation between ECR and cellular density in ML is demonstrated and the ECR may be a useful technique to differentiate between FL and DLBCL.

Modulation of Lipid Kinase PI4KIIα Activity and Lipid Raft Association of Presenilin 1 Underlies γ-Secretase Inhibition by Ginsenoside (20<i>S</i>)-Rg3

Kang, Min Suk,Baek, Seung-Hoon,Chun, Yoon Sun,Moore, A. Zenobia,Landman, Natalie,Berman, Diego,Yang, Hyun Ok,Morishima-Kawashima, Maho,Osawa, Satoko,Funamoto, Satoru,Ihara, Yasuo,Di Paolo, Gilbert,Par American Society for Biochemistry and Molecular Bi 2013 The Journal of biological chemistry Vol.288 No.29

<P>Amyloid β-peptide (Aβ) pathology is an invariant feature of Alzheimer disease, preceding any detectable clinical symptoms by more than a decade. To this end, we seek to identify agents that can reduce Aβ levels in the brain via novel mechanisms. We found that (20<I>S</I>)-Rg3, a triterpene natural compound known as ginsenoside, reduced Aβ levels in cultured primary neurons and in the brains of a mouse model of Alzheimer disease. The (20<I>S</I>)-Rg3 treatment induced a decrease in the association of presenilin 1 (PS1) fragments with lipid rafts where catalytic components of the γ-secretase complex are enriched. The Aβ-lowering activity of (20<I>S</I>)-Rg3 directly correlated with increased activity of phosphatidylinositol 4-kinase IIα (PI4KIIα), a lipid kinase that mediates the rate-limiting step in phosphatidylinositol 4,5-bisphosphate synthesis. PI4KIIα overexpression recapitulated the effects of (20<I>S</I>)-Rg3, whereas reduced expression of PI4KIIα abolished the Aβ-reducing activity of (20<I>S</I>)-Rg3 in neurons. Our results substantiate an important role for PI4KIIα and phosphoinositide modulation in γ-secretase activity and Aβ biogenesis.</P>