• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.22-23
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• 2003

Primordial germ cell (PGC) is the progenitor cell of the germ cell lineage and eventually give rise to gametes that are responsible for creating individual organisms via a fertilization process. This means that PGC is a unique cell that can be converted into individual fish. This advantage of PGCs would make it possible to develop various applications in the field of fish bioengineering. First, PGCs may make it easier to preserve the genetic resources of fish. Cryopreservation of fish eggs or embryos has not been successfully achieved so far. Therefore, the only possible method to preserve genetic resources of fishes is to raise fish as live individuals. If PGCs isolated from various fishes could be cryopresewed, these cells could be converted into live fishes via germ-line chimera production. This is particularly useful for preserving genetic materials of endangered species. Even if the species of interest were to become extinct, it could be recovered by the transplantation of cryopreserved PGCs into the embryos of a closely related species. Another application of this technology is in what could be termed "surrogate broodstock technology". (중략)

• Clinical and Experimental Reproductive Medicine
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• 제39권3호
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• pp.95-106
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• 2012

It has been revealed that multiple cohorts of tertiary follicles develop during some animal estrous cycle and the human menstrual cycle. To reach developmental competence, oocytes need the support of somatic cells. During embryogenesis, the primordial germ cells appear, travel to the gonadal rudiments, and form follicles. The female germ cells develop within the somatic cells of the ovary, granulosa cells, and theca cells. How the oocyte and follicle cells support each other has been seriously studied. The latest technologies in genes and proteins and genetic engineering have allowed us to collect a great deal of information about folliculogenesis. For example, a few web pages (http://www.ncbi.nlm. nih.gov; http://mrg.genetics.washington.edu) provide access to databases of genomes, sequences of transcriptomes, and various tools for analyzing and discovering genes important in ovarian development. Formation of the antrum (tertiary follicle) is the final phase of folliculogenesis and the transition from intraovarian to extraovian regulation. This final step coordinates with the hypothalamic-pituitary-ovarian axis. On the other hand, currently, follicle physiology is under intense investigation, as little is known about how to overcome women's ovarian problems or how to develop competent oocytes from in vitro follicle culture or transplantation. In this review, some of the known roles of hormones and some of the genes involved in tertiary follicle growth and the general characteristics of tertiary follicles are summarized. In addition, in vitro culture of tertiary follicles is also discussed as a study model and an assisted reproductive technology model.

• 천문학회지
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• 제40권4호
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• pp.157-160
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• 2007

I present a model to explain the mass segregation and shallow mass functions observed in the central parts of starburst stellar clusters. The model assumes that the initial pre-stellar cores mass function resulting from the turbulent fragmentation of the proto-cluster cloud is significantly altered by the cores coalescence before they collapse to form stars. With appropriate, yet realistic parameters, this model based on the competition between cores coalescence and collapse reproduces the mass spectra of the well studied Arches cluster. Namely, the slopes at the intermediate and high mass ends, as well as the peculiar bump observed at $6M_{\bigodot}$. This coalescence-collapse process occurs on a short timescale of the order of the free fall time of the proto-cluster cloud (i.e., a few $10^4$ years), suggesting that mass segregation in Arches and similar clusters is primordial. The best fitting model implies the total mass of the Arches cluster is $1.45{\times}10^5M_{\bigodot}$, which is slightly higher than the often quoted, but completeness affected, observational value of a few $10^4M_{\bigodot}$. The model implies a star formation efficiency of ${\sim}30$ percent which implies that the Arches cluster is likely to a gravitationally bound system.

• 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.

• 한국균학회지
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• 제27권4호통권91호
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• pp.249-251
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• 1999

노루궁뎅이버섯의 재배방법에 따른 수량은 병재배로 재배하였을 때 356 g/850 ml으로, 봉지(pot)재배하였을 때의 810 g/2500 ml보다 더 높았다. 그러나 회수율은 병(850 ml)에 재배하였을 때 147.8%로 봉지(pot)에 재배하였을 때의 114.3% 보다 높았다 발이 유기시 균긁기는 하지 않은 것이 좋았으며 특히 병마개를 막아둔 상태에서 발이시키는 방법이 수량도 가장 많고 생물적 효율도 높았다. 노루궁뎅이버섯의 원목재배 수종은 참나무, 물오리나무, 포플러, 아카시나무 원목 순으로 좋았다. 참나무원목은 수량이 $1195.5\;g/0.1\;m^3$, 생물학적 효율이 17.3%, 초발이 소요일수는 69일, 개체중은 143 g이었다.

• 천문학회보
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• 제38권1호
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• pp.40.1-40.1
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• 2013

The HI ring serendipitously found in the Leo I galaxy group is unique in size in the Local Universe. It is ~200kpc in diameter with MHI~$1.67{\times}109M{\odot}$, surrounding a pair of early type galaxies M105 and NGC 3384. Its origin is still under debate whether it is the remnant of formation of a galaxy group (primordial) or formed from stripped material during galaxy-galaxy interaction (tidal origin). Intriguingly a number of dwarf galaxies have been identified along the gas ring (with or without optical counterpart). Various properties of these dwarf galaxies such as dark matter content, color, and/or metallicity will allow us to pin down the origin of this large scale HI ring. We have obtained a mosaicked CFHT MegaCam image and the EVLA HI cube of the large scale gas ring. In this work we present optical and gas properties of dwarf galaxies identified in the CFHT data.

• 천문학논총
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• 제22권4호
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• pp.169-175
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• 2007

The international cooperation project CIBER (Cosmic Infrared Background ExpeRiment) is a rocket-borne instrument, of which the scientific goal is to measure the cosmic near-infrared extra-galactic background to search for signatures of primordial galaxy formation. CIBER consists of a wide-field two-color camera, a low-resolution absolute spectrometer, and a high-resolution narrow-band imaging spectrometer. Currently, all the subsystems have been built, and the integration, testing, and calibration of the CIBER system are on process for the scheduled launch in June 2008.

• 천문학논총
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• 제21권2호
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• pp.21-26
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• 2006

A Korean team (Korea Astronomy and Space Science Institute, Korea Basic Science Institute, and Kyung Hee University) takes part in an international cooperation project called CIBER (Cosmic Infrared Background ExpeRiment), which has begun with Jet Propulsion Laboratory (JPL) in USA and Institute of Space and Astronautical Science (ISAS) in Japan. CIBER is a rocket-borne instrument, of which the scientific goal is to measure the cosmic near-infrared extra-galactic background to search for signatures of primordial galaxy formation. CIBER consists of a wide-field two-color camera, a low-resolution absolute spectrometer, and a high-resolution narrow-band imaging spectrometer. The Korean team is in charge of the ground support electronics and manufacturing of optical parts of the narrow-band spectrometer, which will provide excellent opportunities for science and technology to Korean infrared groups.

• 현장농수산연구지
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• 제4권1호
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• pp.65-69
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• 2002

버섯수량성에 미치는 오존의 영향을 조사한 결과는 다음과 같다. 1. 느타리버섯 생육과정중 오존처리 결과, 버섯 대길이는 짧아지고, 대와 갓 직경은 커지는 경향이 있으며 수량은 관행에 비하여 7% 증수하였다. 2. 양송이 생육과정중 오존처리 결과, 버섯 대 길이는 짧아지고, 대와 갓 직경은 커지는 경향이 있으며 수량은 관행에 비하여 4% 증수하였다. 3. 팽이버섯 생육과정중 오존처리결과, 초발이 소요일수가 2일 늦어지고, 발이 개체수가 적었으나 수량은 3% 증수하였다.

• 수완나부미
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• 제11권2호
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• pp.59-83
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• 2019

The Chinese Belt Road initiatives in the Southeast Asian countries marked a new chapter in the development of China political influence on this region. This article looks at the initiative from the cultural dimension and aims to place its narrative as the entry point to understand the use of identity politics in Asian countries that target the Chinese diaspora. This topic relates to the primordial sentiments of Southeast Asian nations amid massive Chinese investment in the region. The issue of Chinese investments under the Belt Road Initiative corridor has a relationship with the formation of anti-Chinese discourse and anti-communist in some Southeast Asian countries. We took the cases of Indonesian and Malaysian elections to observe the use of identity politics and anti-Chinese political discourse in Southeast Asia. In both cases, a common issue emerged, that of the strengthening both Islamic and indigenous sensibilities. The establishment of ASEAN during the Cold War may be seen then as an anti-thesis to emerging Chinese power. However, anti-Chinese and anti-communism sentiments were not enough to unite the forces of the nations of Southeast Asia. We have concluded that brotherhood, mutual prosperity, and anti-neo-colonialism are yet to be fostered completely to make a distinct ASEAN identity.