• Title/Summary/Keyword: MAG3

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PHOTOMETRIC PROPERTIES OF THE BRIGHT LENTICULAR GALAXY NGC 5102

  • Sohn, Young-Jong;Chun, Mun-Suk;Byun, Yong-Ik
    • Journal of The Korean Astronomical Society
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    • v.24 no.2
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    • pp.151-159
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    • 1991
  • Using the photographic imagery of the SO galaxy NGC 5102, the equivalent luminosity profile and the fractional integrated luminosity curve have been derived. Several photometric parameters of the galaxy, such as a total magnitude ($B_T$), equivalent radius ($r^*_e$), effective surface brightness (${\mu}^*_e$), and concentration indices ($C_{21}$, $C_{32}$) were derived from the luminosity profiles. According to the decomposition method from the nonlinear least squares fitting, photometric parameters of the bulge (${\mu}_e$, $r_e$) and the exponential disk (${\mu}(0)$, ${\alpha}^{-1}$), and the bulge to total luminosity ratio (B/T) were obtained. The derived central disk surface brightness (${\mu} (0)\;=\;22.06\;{\pm}\;0.18\;mag/\Box"$) and the evaluated B/T ratio (= 0.52) of the NGC 5102 are close to the mean values (${\mu} (0)\;=\;21.65\;{\pm}\;0.3\;mag/\Box"$, B/T=0.63) of the SO galaxies. Analysis showed that a lens-like hump is embedded in the equivalent luminosity profile of the NGC 5102.

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The Change of Ginsenoside Composition in American Ginseng (Panax quinquefolium) Extract by the Microwave and Vinegar Process (서양삼 추출물의 초단파 및 식초 처리에 의한 인삼 사포닌 성분 변화)

  • Jo, Hee Kyung;Gwak, Hyeon Hui;Im, Byung Ok;Cho, Soon Hyun;Ko, Sung Kwon
    • Korean Journal of Pharmacognosy
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    • v.45 no.2
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    • pp.107-112
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    • 2014
  • The purpose of this study is to develop a new preparation process of American ginseng (Panax quinquefolium) extract featuring high concentration of ginsenoside $Rg_3$, $Rg_5$, and $Rk_1$, Red ginseng special components. Chemical transformation from ginseng saponin glycosides to prosapogenin was analyzed by the HPLC. Extracts of American ginseng were processed under several treatment conditions of microwave and vinegar (about 14% acidity). The results showed that the quantity of ginsenoside $Rg_3$ increased by over 0.9% at the 20 minutes of the pH 2~4 vinegar and microwave American ginseng ethanol extract compared with other process times. The result of MAG-20 indicates that the American ginseng microwave and vinegar-processed American ginseng extracts (about 14% acidity) treated for 20 minutes produced the highest amount of ginsenoside $Rg_3$ (0.969%), $Rg_5$ (1.071%), and $Rk_1$ (0.247%). Besides, MAG-15 indicates that the microwave - and vinegar-processed American ginseng extracts (about 14% acidity) treated for 15 minutes produced the highest amount of ginsenoside $Rg_3$ (0.772%), $Rg_5$ (1.330%), and $Rk_1$ (0.386%). This indicates that American ginseng treated with microwave and vinegar had the quantity of the ginsenoside $Rg_3$ over 32 times the amount of the ginsenoside $Rg_3$ (which was not found in raw and American ginsengs) in the average commercial Red ginseng.

A NEAR-INFRARED STUDY OF THE HIGHLY-OBSCURED ACTIVE STAR-FORMING REGION W51B

  • Kim, Hyo-Sun;Nakajima, Yasushi;Sung, Hwan-Kyung;Moon, Dae-Sik;Koo, Bon-Chul
    • Journal of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.17-28
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    • 2007
  • We present wide-field $JHK_s$-band photometric observations of the three compact H II regions G48.9-0.3, G49.0-0.3, and G49.2-0.3 in the active star-forming region W51B. The star clusters inside the three compact H II regions show the excess number of stars in the $J-K_s$ histograms compared with reference fields. While the mean color excess ratio $(E_{J-H}/E_{H-K_s})$ of the three compact H II regions are similar to ${\sim}2.07$, the visual extinctions toward them are somewhat different: ${\sim}17$ mag for G48.9-0.3 and G49.0-0.3; ${\sim}23$ mag for G49.2-0.3. Based on their sizes and brightnesses, we suggest that the age of each compact H II region is ${\leq}2\;Myr$. The inferred total stellar mass, ${\sim}1.4{\times}10^4M_{\odot}$, of W51B makes it one of the most active star forming regions in the Galaxy with the star formation efficiency of ${\sim}10%$.

Usefulness of Routine Renal Sonography Screening for Healthy Infants with Isolated Single Umbilical Artery (단일 제대 동맥을 가진 건강한 신생아에서 신장 초음파 검사의 유용성)

  • Kang, Ju-Mi;Song, Eun-Song;Kuk, Jin-Hwa;Lee, Hyung-Sin;Kim, So-Young;Choi, Young-Youn
    • Clinical and Experimental Pediatrics
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    • v.46 no.9
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    • pp.854-857
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    • 2003
  • Purpose : It is known that single umbilical artery is frequently associated with gastrointestinal or urogenital anomaly, however, routine renal sonography has been debated in healthy neonate with isolated single umbilical artery. This study is designed to determine the usefulness of routine renal sonography in apparently healthy infants with an isolated single umbilical artery. Methods : Thirty healthy neonates with a single umbilical artery without a major anomaly from January 1995 to July 2002 were enrolled. The authors investigated the clinical background of babies and their mothers after renal sonography after 72 hours of age. When the abnormalities were found at the first renal sonography, the severity of hydronephrosis and degree of obstruction and renal function were analyzed by follow up renal sonography, voiding cystourethrography(VCUG) and technetium-99m-dimercaptosuccinic acid(DMSA) scan or technetium-99m-mercaptoacetyl-triglycerine (MAG3) scan. Results : Among the 30 healthy patients with isolated single umbilical artery, five patients(16.7%) showed abnormalities on first renal sonography with one major(3.3%) and four(13.4%) minor renal anomaly(minimal or mild hydroneohrosis). One major renal anomaly(severe hydronephrosis) showed severe decreased renal function on MAG3 scan without reflux, and the other four minor regressed spontaneously on follow up study. Conclusion : The value of routine early renal sonograpy for detecting renal anomaly in healthy infants with an isolated single umbilical artery remained unclear because most of the anomalies would regress spontaneously in the follow up study.

A Study on the Design and Fabrication of X-band Power Amplifier for SART (SART용 X-밴드 전력증폭기의 설계와 제작에 관한 연구)

  • 김철수;김미숙;최병하
    • Journal of the Korean Institute of Navigation
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    • v.23 no.3
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    • pp.29-34
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    • 1999
  • In this paper, an X-band power amplifier using GaAs FET was designed and fabricated, which is to be used as SART transmitter sweeping at the frequency range of 9.2 GHz~9.5 GHz. The amplifier is consist of two stages using ATF-46101 FET of Hewllett-Packard. Finally, the amplifier using microstrip line matching solution shows that MAG is 23 dB at the center frequency of 9.35 GHz.

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Launch Environment Test for Scale magNetospheric and Ionospheric Plasma Experiment (SNIPE) Engineering Qualification Model (초소형위성 SNIPE(Scale Magnetospheric and Ionospheric Plasma Experiment) 시제인증모델의 발사환경시험 및 분석)

  • Kim, Min-Ki;Kim, Hae-Dong;Choi, Won-Sub;Kim, Jin-Hyung;Kim, KiDuck;Kim, Ji-Seok;Cho, Dong-Hyun
    • Journal of Space Technology and Applications
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    • v.1 no.3
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    • pp.319-336
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    • 2021
  • This paper discusses the results of launch environment tests for the engineering qualification model (EQM) of nanosatellite Scale magNetospheric and Ionospheric Plasma Experiment (SNIPE) for scientific missions and lessons learned for the design of nanosatellites. SNIPE is a group of four formation-flying 6U nanosatellites with a range of payloads for missions including space weather measurement. We developed the EQM to verify the preliminary design prior to fabricating the flight model. Launch environment test of EQM was conducted for the first time in 2019, and all failures were corrected and verified at the second test conducted in 2021. A notable point of the two tests is that the nanosatellite deployer used in the first test is different from that of the second test. The second deployer has the capability to fix the internal satellite whereas the first deployer just contains and deploys the satellite. Thus actual mechanical loads the satellite receives is reduced for the second test compared to the first test. This work compares the mechanical responses of two tests and proposes general guidelines for structural design of nanosatellites.

Effects of Low Power Laser on Pain Response and Axonal Regeneration in Rat Models with Sciatic Nerve Crush Injury

  • Lee, Hong-Gyun;Kim, Yong-Eok;Min, Kyung-Ok;Yoo, Young-Dae;Kim, Kyung-Yoon;Kim, Gye-Yeop
    • Journal of International Academy of Physical Therapy Research
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    • v.3 no.1
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    • pp.345-355
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    • 2012
  • This study purposed to examine the effect of low power laser on pain response and axonal regeneration. In order to prepare peripheral nerve injury models, we crushed the sciatic nerve of Sprague-Dawley rats and treated them with low power laser for 21 days. The rats were divided into 4 groups: normal group(n=10); control group(n=10) without any treatment after the induction of sciatic nerve crush injury; experimental group I(n=10) treated with low power laser(0.21$mJ/mm^2$) after the induction of sciatic nerve crush injury; and experimental group II(n=10) treated with low power laser(5.25$mJ/mm^2$) after the induction of sciatic nerve crush injury. We measured spontaneous pain behavior(paw withdrawal latency test) and mechanical allodynia(von Frey filament test) for evaluating pain behavioral response, and measured the sciatic function index for evaluating the functional recovery of peripheral nerve before the induction of sciatic nerve crush injury and on day 1, 7, 14 and 21 after the induction. After the experiment was completed, changes in the H & E stain and toluidine blue stain were examined histopathologically, and changes in MAG(myelin associated glycoprotein) and c-fos were examined immunohistologically. According to the results of this study, when low power laser was applied to rat models with sciatic nerve crush injury for 21 days and the results were examined through pain behavior evaluation and neurobehavioral, histopathological and immunohistological analyses, low power laser was found to affect pain response and axonal regeneration in both experimental group I and experimental group II. Moreover, the effect on pain response and axonal regeneration was more positive in experimental group I to which output 0.21$mJ/mm^2$ was applied than in experimental group II to which 5.25$mJ/mm^2$ was applied.

SEOUL NATIONAL UNIVERSITY 4K×4K CAMERA (SNUCAM) FOR MAIDANAK OBSERVATORY

  • Im, Myung-Shin;Ko, Jong-Wan;Cho, Yun-Seok;Choi, Chang-Su;Jeon, Yi-Seul;Lee, In-Duk;Ibrahimov, Mansur
    • Journal of The Korean Astronomical Society
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    • v.43 no.3
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    • pp.75-93
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    • 2010
  • We present the characteristics of the Seoul National University 4k Camera (SNUCAM) and report its performance on the 1.5m telescope at the Maidanak observatory in Uzbekistan. SNUCAM is a CCD camera with a pixel scale of 0.266" in $4096{\times}4096$ format, covering $18.1'{\times}18.1'$ field of view on the 1.5m. The camera is currently equipped with Bessell UBVRI, $H{\alpha}$, SDSS ugriz, and Y-band filters, allowing us to carry out a variety of scientific programs ranging from exoplanet studies to survey of quasars at high redshift. We examine properties of SNUCAM such as the bias level and its temporal variation, the dark current, the readout noise, the gain, the linearity, the fringe patterns, the amplifier bias, and the bad pixels. From our observations, we also constructed the master fringe frames in I-, z-, and Y-band. We outline some of the current scientific programs being carried out with SNUCAM, and demonstrate that SNUCAM on the 1.5m can deliver excellent images that reach to the $5-{\sigma}$ detection limits of R~25.5 mag and z~22.7 mag in 1 hour total integration.

Application of Yonsei-Yale isochrones to Globular Clusters in gri band

  • Lim, Dong-Wook;Han, Sang-Il;Chun, Sang-Hyun;Kim, Myo-Jin;Shon, Young-Jong
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.2
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    • pp.83.1-83.1
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    • 2010
  • Recent observations of Sloan Digital Sky Survey (SDSS) for the ugriz filters have provided the largest and the most homogeneous photometric database. Especially, the ugriz systems have been used in many telescopes, such as SDSS, CFHT, and Gemini, and will be applied next generation large telescopes. In addition, many stellar evolution models, like as PADOVA, BaSTI and DSEP, have introduced theoretical isochrones in ugriz system, to apply the isochrones into the photometry of stars in globular clusters. In this study, we transformed Yonsei-Yale($Y^2$) isochrones to ugriz photometric system and fit the isochrones to the (g-r, r), (g-i, r), and (r-i, r) CMDs of 13 globular clusters (Chun et al. 2009, Clem et al. 2008, An et al. 2008). We found that the derived ages from $Y^2$-isochrones are 1~3Gyr younger and the estimated distance moduli are 0.3mag larger than the values inferred from the other isochrones in r-band. Also, the E(B-V) are 0.02~0.04mag less than those estimated from the other models. The ages of each globular cluster estimated from $Y^2$-isochrones are 12~14Gyr and distance moduli show good agreement with previous studies. From this result, we confirmed the availability of the $Y^2$-isochrones in gri filters. However, it is a problem which will improve that E(B-V) values obtained from $Y^2$-isochrones are too small. Finally, the result of this study is expected to be used research of globular cluster in ugirz photometric system.

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