• 한국어병학회지
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• 제19권3호
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• pp.197-206
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• 2006

2004~2005년까지 수입산 pearl gourami (Trichogaster leeri), dwarf gourami (Colisa lalia), silver gourami (Trichogaster microlepis), blue gourami (Trichogaster trichopterus sumatranus) 그리고 freshwater angelfish (Pterophyllum scalare) 등 5 어종을 대상으로 iridovirus 감염 실태를 PCR 방법을 사용하여 조사하였다. 채집한 56 samples 중 11 samples에서 PCR 양성 반응이 관찰되었고, pearl gourami에서 31.8% (7/22)로 가장 높은 감염 빈도를 나타내었다. 그 다음으로 dwarf gourami, blue gourami, silver gourami 순으로 나타났으며, freshwater angelfish에서는 iridovirus가 검출되지 않았다. 자연 감염된 관상어종의 비장으로부터 iridovirus의 핵산을 분리하여 검출한계 PCR 방법으로 viral DNA의 양을 비교하였으며, dwarf gourami에 비해 pearl gourami에서 더 많은 viral DNA가 검출되는 것을 확인하였다. 자연 감염이 확인된 pearl gourami groups는 실험실 환경에서 100% 폐사하였고, 폐사어 중 57% 이상이 PCR 양성 반응을 나타내었다. PstⅠfragment의 염기서열 비교에서 pearl gourami와 dwarf gourami에서 분리한 iridoviruses는 중국의 mandarinfish (Siniperca chuatsi)에서 분리된 infectious spleen and kidney necrosis virus (ISKNV)와 99% 이상의 매우 높은 상동성을 나타내었다.

• 천문학회보
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• 제38권2호
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• pp.65.1-65.1
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• 2013

Our understanding of how brown dwarfs form is limited by observational evidence. We report identification of a L328-IRS as a proto-brown dwarf embedded in an isolated dense molecular core. This source exhibits typical properties of a protostar, however, its luminosity (~0.05 $L{\odot}$) is far below than expected from the least massive protostar by the standard star formation theory. The most likely mass accretion rate (~2.4 10-7 $M{\odot}$ yr-1) inferred from its small bipolar outflow is an order of magnitude less than the canonical value for a protostar. The mass available in its envelope is less than 0.1 $M{\odot}$. These points suggest that L328-IRS will accrete the mass of a brown dwarf, but not that of a star. L328 is found to be fairly well isolated from other nearby clouds and seems to be forming three sub-cores simultaneously through a gravitational fragmentation process. Altogether with these, our direct detection of inward motions in L328 which harbors this proto-brown dwarf clearly supports the idea that a brown dwarf forms like a normal star.

• 복식문화연구
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• 제9권3호
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• pp.485-500
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• 2001

The purpose of this study is to develop the formal wear for social activity of dwarf. Second investigation for choices of designs based upon data from the first questionnaire investigation, led us to make proposals for design, pattern production, garment-cutting and dressmaking. The effect of wearing the made-up garments was carefully evaluated in order to establish principles for the development of clothes for dwarf. Conclusion is as follow. Dwarf felt uneasy in conventional street dress. When buying clothes their most important criteria was design wanted clothes that would help them to look taller. Analysis of design preference to complement perceived physical weak points revealed: 'a pink ensemble' comprising of a high-waist, one-piece dress, and a black slacks suit comprising of a striped, single-breasted, tailored jacket, and straight-type slacks and blouse. It was found that a bolero jacket and a high-waist, ankle-length, one-piece dress helped create an optical illusion of increased height, for both the wearer and an observer. A pastel ton-pink, one-piece also created this effect on small bodily types, as well as offering a silky, mellow attractiveness. A suit of a striped, single-breasted tailored jacket, and straight-type slacks and blouse, created the two fold illusion of disguising hip imbalance with the length of the jacket and drawing an onlooker\`s gaze to the wearer\`s face through the tailored collar, they also looked taller due to the stripes.

• 천문학회보
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• 제41권2호
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• pp.63.2-63.2
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• 2016

One of the well-known problems in the lambda cold dark matter (${\Lambda}CDM$) models is a missing satellite problem. The slope of the mass function of low mass galaxies predicted by ${\Lambda}CDM$ models is much steeper than that based on the luminosity function of dwarf galaxies in the local universe. This implies that the model prediction is an overestimate of low mass galaxies, or that the current census of dwarf galaxies in the local universe may be an underestimate of dwarf galaxies. Previous studies of galaxy luminosity functions to address this problem are based mostly on the sample of galaxies brighter than Mv ~ -10 in the nearby galaxies. In this study we try to search for ultra-faint galaxies (UFDs), which are much fainter than those in the previous studies. We use multi-field HST ACS images of M60 in the archive. M60 is a giant elliptical galaxy located in the east part of the Virgo cluster, and hosts a large population of globular clusters and UCDs. Little is known about the dwarf galaxies in this galaxy. UFDs are much fainter, much smaller, and have lower surface brightness than normal dwarf galaxies so HST images of massive galaxies are an ideal resource. We present preliminary results of this search.

• 한국산림과학회지
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• 제101권4호
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• pp.635-639
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• 2012

뽕나무 오갈병 파이토플라스마 매개곤충을 알아보기 위하여 뽕나무 재배지에서 채집된 곤충 중 흡즙성 곤충 3 종(Hishimonas sellatus, Bothrogonia japonica and Balclutha punctata)를 선발하였다. 이들 흡즙성 곤충을 뽕나무 이병주에서 흡즙시킨 다음 건전 뽕나무와 일일초로 전반시킨 결과, 마름무늬매미충(H. sellatus)과 B. punctata이 파이토플라스마를 전반하였다. 뽕나무에서는 전형적인 오갈 증상을 보였지만 일일초에서는 가지가 가늘게 늘어지며, 잎은 총생하고 작아지는 빗자루증상이 나타났다. 매개충과 매개전염시킨 뽕나무와 일일초에 대하여 R16F2n/R2 프라이머로 PCR 검정 결과 끝검은말매미충을 제외한 모든 시료에서 파이토플라스마가 검출되었다.

• The Plant Pathology Journal
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• 제17권3호
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• pp.164-168
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• 2001

Rice black-streaked dwarf virus (RBSDV) and Maize rough dwarf virus (MRDV) are closely related viruses. Since the two viruses produce identical symptoms on maize, barley, and wheat, diagnosis of infected plants is difficult. Previously, we reported that partial cDNA clones of RBSDV S5 and S6 from the Japanese isolate (RBSDV-H) have lower sequence homology to MRDV than do cDNA clones from other genomic segments. In order to test whether cDNA clones of RBSDV-H S5 and S6 can be used for molecular diagnosis, RBSDV field isolates from Korea and from Hokkaido, Japan were tested in dot blot hybridizations probed with RBSDV-H S5 and S6 cDNA colnes. Hybridization with these probes was more intense against the RBSDV genome than against the MRDV genome. Therefore, RBSDV-H S5 and S6 cDNA clones can be used to differentiate between the two viruses. Furthermore, RBSDV-H S5 and S6 clones reacted more strongly against the viruses from stunted maize plants from Korean fields than to MRDV, indicating that RBSDV may be the causal disease agent in maize plants in Korea.

• 천문학회보
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• 제36권2호
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• pp.113.1-113.1
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• 2011

The Leo ring in the M96 group is unique in its morphology and size among the intergalactic gas features found in nearby universe. Its ring-like structure of 200 kpc on diameter appears to be orbiting around the M105-NGC 3384 pair with $1.67{\times}109\;M{\odot}$ of HI gas. While the origin of the ring - whether it is primordial or tidally stripped - is yet unclear, the optical and gas properties of dwarf galaxies associated with the gas ring help us to understand the formation process of this large scale intergalactic HI cloud. At the first step, we present the optical catalog of dwarf galaxy candidates in the Leo ring using deep optical images with MegaCam on the CFHT. Image convolution method is used in order to detect very faint dwarf galaxies. Comparing the ALFALFA HI data from the literature, we have identified that 4 dwarf candidates coexist with HI clumps. There are also 27 HI dwarfs with no optical counterpart and 12 optical dwarfs with no HI clump. In this work, we probe the optical and global gas properties of these dwarfs.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2009년도 한국우주과학회보 제18권2호
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• pp.35.2-35.2
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• 2009

One possible channel for the formation of dwarf galaxies involves birth in the tidal tails of interacting galaxies. We report the detection of a bright UV tidal tail and several young tidal dwarf galaxy candidates in the post-merger galaxy NGC 4922 in the Coma cluster. Based on a two-component population model (combining young and old stellar populations), we find that its light predominantly comes from young stars (a few Myr old). The Galaxy Evolution Explorer (GALEX) ultraviolet data played a critical role in the parameter (age and mass) estimation. Our stellar mass estimates of the tidal dwarf galaxy candidates are ~10^{6-7} M_sun, typical for dwarf galaxies.

• 천문학회보
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• 제43권2호
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• pp.54.3-55
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• 2018

We present the physical and environmental properties of nearby dwarf elliptical-like galaxies. The present sample consists of ~ 1,100 dwarf elliptical-like galaxies within redshifts 0.01. The morphological types of the present study were determined by Ann, Seo, and Ha (2015) who classified the dwarf elliptical-like galaxies by the five subtypes of dS0, dE, dSph, dEbc, and dEblue. We examine their star formation history using STARLIGHT. The star formation history of dwarf elliptical-like galaxies depends on their subtypes. The luminosities of dS0, dE, and dSph galaxies are dominated by the extremely old stars (${\geq}10^{10}yr$) with $z{\approx}0.0004$ while those of dEbc and dEblue galaxies are mainly due to the young (${\sim}10^7yr$) stars together with the nearly equal contribution by extremely young stars (${\sim}10^6yr$) and old (${\sim}10^9yr$) stars. Young populations have a variety of metallicity, from z=0.0001 to z = 0.04, while old populations have metallicity of z = 0.0001 and z = 0.0004. While the formation history of stars older than ~1010yr depends mainly on the luminosity of galaxies, the formation history of stars younger than ~108yr is mainly affected by their environment. However, luminosity and environment are equally important for the star formation history if there is no star formation at the early phase of galaxy formation.

• 천문학회보
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• 제43권2호
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• pp.53.2-53.2
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• 2018

We present newly discovered dwarf galaxy candidates in deep and wide-field images of NGC 1291 obtained with KMTNet. Through a visual inspection, we find ~ 13 candidates, for which central surface brightness ranges from ${\mu}_{0,R}{\sim}22.5$ to $26.5mag\;arcsec^{-1}$. Adopting the distance to NGC 1291, the candidate dwarfs are brighter than $M_R=-12.5mag$ and their effective radii range from 350 pc to 1.4 kpc. Structural and photometric properties of dwarf candidates near NGC 1291 appears to be consistent with those of ordinary dwarf galaxies in nearby galaxies. We conduct the imaging simulation in order to find an optimal way to detect dwarf galaxies in KMTNet images and to test the completeness of our detection algorithm. We plan to apply this method to deep KMTNet images of other nearby galaxies obtained through KMTNet Nearby Galaxy Survey (KNGS).