• 천문학논총
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• 제15권spc1호
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• pp.31-38
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• 2000

We have presented detected molecules, atoms, radicals, ions, and dimers in the atmospheres of planets and comets from Earth-based and spaceborne observatories during the last 3 decades. We have reviewed spectroscopic studies on the auroral emissions and air glows of the giant planets, and briefly summarized spectroscopic observations of dimers in the atmospheres of the giant planets and Titan. In particular, we highlighted the recent detections of new molecular emissions and absorptions in the spectra of the giant planets, Titan, and recent bright comets from spaceborne or ground-based observatories. We also reviewed current models and theories of the origin and evolution of the solar system, and implications of isotopic ratios in these atmospheres.

• 천문학논총
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• 제25권1호
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• pp.1-13
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• 2010

Astrochemistry provides powerful tools to understand various cosmic phenomena, including those in our solar system to the large-scale structure of the universe. In addition, the chemical property of an astronomical body is a crucial factor which governs the evolution of the system. Recent progress in astrophysical theories, computational modelings, and observational techniques requires a detailed understanding of the interactions between the constituents of an astronomical system, which are atoms and molecules within the system. Especially the far-infrared/sub-millimeter wave range, which is called as the last frontier in astronomical observations, contains numerous molecular lines, which may provide a huge amount of new information. However, we need an astrochemical understanding to use this information fully. Although this review is very limited, I would like to stress the importance of astrochemical approach in this overview for the field, which is getting much more attention than ever before.

• BMB Reports
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• 제39권5호
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• pp.511-515
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• 2006

Alanine aminotransferase (AAT) is mainly synthesized in the liver, and its level in mammalian serum is elevated after acute phase induction. Here we demonstrated that sheep anti-human AAT antibody cross-reacted with amphioxus humoral fluids as well as human serum; and the concentration of AAT in the humoral fluids in amphioxus increased after the acute challenge with lipopolysaccharide, while the level of total proteins remains unchanged. These suggest the presence of the same acute phase response pattern in amphioxus, as observed in some mammalian species. Immunohistochemically, AAT was localized in the hepatic diverticulum, ovary and testis. It appears that the hepatic diverticulum in amphioxus is functionally homologous to the vertebrate liver in respect of AAT synthesis, supporting the hypothesis that the vertebrate liver evolved from the hepatic diverticulum of an amphioxus-like ancestor during early chordate evolution.

• Journal of Dairy Science and Biotechnology
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• 제25권2호
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• pp.21-28
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• 2007

Recently, the field of microbiology has been transformed by huge increasing number of publicly available whole-genome sequences. This sequence information has significantly enhanced our understanding of the physiology, genetics, and evolutionary development of bacteria. Among the gastrointestinal microorganisms, bifidobacteria represent the most important human commensals because of their contribution to maintaining a balanced gastrointestinal tract microbiota. In recent years bifidobacteria have drawn much scientific attention due to their use as live bacteria in numerous food products with various health-related claims. For this reason, these bacteria constitute a growing area of interest with respect to genomics, molecular biology, and genetics. Recent genome sequencing of a number of bifidobacterial species has allowed access to the complete genetic make-up of these bacteria. This review will focus how genomic data has allowed us to understand bifidobacterial evolution, while also revealing genetic functions that explains their presence in the particular ecological environment of the gastrointestinal tract.

• Animal Systematics, Evolution and Diversity
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• 제29권3호
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• pp.253-258
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• 2013

Two specimens of Chromis albicauda were collected from Jeju Island, Korea. The species is most similar to C. analis, but is distinguishable by the presence of a white caudal fin when alive, 4-5 scale rows on the anterior portion of the preorbital, and a blackish blotch around anal opening. The results of a molecular analysis based on mitochondrial DNA 16S rRNA sequences confirm that the two individuals are not C. analis but C. albicauda as the genetic distance between the two species is 0.044. A comparison of the two individuals of C. albicauda with yellow chromis shows that none of the previously reported yellow chromis is C. analis, but rather they are C. albicauda. Herein, we suggest the new Korean name "Huin-ggo-ri-no-rang-ja-ri-dom" for C. albicauda.

• 천문학회지
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• 제42권2호
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• pp.17-26
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• 2009

We estimate the enclosed mass profile in the central 10 pc of the Milky Way by analyzing the infrared photometry and the velocity observations of dynamically relaxed stellar population in the Galactic center. HST/NICMOS and Gemini Adaptive Optics images in the archive are used to obtain the number density profile, and proper motion and radial velocity data were compiled from the literature to find the velocity dispersion profile assuming a spherical symmetry and velocity isotropy. From these data, we calculate the the enclosed mass and density profiles in the central 10 pc of the Galaxy using the Jeans equation. Our improved estimates can better describe the exact evolution of the molecular clouds and star clusters falling down to the Galactic center, and constrain the star formation history of the inner part of the Galaxy.

• 천문학회보
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• 제43권1호
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• pp.48.1-48.1
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• 2018

SPHEREx의 중요 임무 중 하나는 $0.75{\mu}m$와 $5{\mu}m$ 사이에서 $H_2O$, CO, $CO_2$, XCN, OCS, 그리고 $CH_3OH$와 같은 얼음 분자의 전천 탐사 스펙트럼을 제공하는 것이다. 이러한 얼음 분자는 성간분자운의 먼지 티끌 표면에서 생성되어 별 탄생의 필연적 산물이며, 행성이 형성되는 원시행성계원반에서 다양한 변화를 겪게 되고, 복잡한 유기분자를 합성하게 된다. 하지만 충분하지 않은 관측 자료로 인해, 얼음 분자의 진화에 대한 이해가 미약한 상태이다. 현재까지는 근적외선에서 충분히 밝은 100 여개의 배경별이나 원시성에 대해서만 얼음 스펙트럼을 관측할 수 있었다. SPHEREx를 이용한 고감도 전천 탐사 미션은 약 20,000 여개의 배경별과 원시성에 대해 얼음 분자 스펙트럼을 제공할 것이다. 이렇게 100 배 이상 늘어난 샘플 스펙트럼 수로 인해, 얼음 분자의 진화에 대해서 통계적으로 의미있는 연구가 가능해 질 것이다. 본 발표에서는 SPHEREx의 Ice Program을 소개하고, 기대되어지는 결과에 대해서 논의하고자 한다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1455-1457
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• 2008

Cell adhesion is a coordinated process involving initial binding of integrin receptors to extracellular matrix (ECM), recruitment of adhesion proteins, and focal adhesion assembly. The formation of mechanically stable focal adhesion assembly of cells within surrounding ECM is a key parameter to direct numerous cellular functions including cell migration, differentiation, and apotosis. With current cell adhesion assays, it is difficult to understand contributions of each coordinated event on evolution of cell adhesion strengthening since cells spontaneously spread upon their adhesion to the substrate, thus remodeling their cytoskeletal structure. In this presentation, novel approaches for analysis of cell adhesion strengthening process based on the combination of mechanical device, micro-patterned substrates, and molecular biological techniques will be discussed.

• 한국연소학회지
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• 제14권2호
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• pp.32-41
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• 2009

The transported probability density function model combined with the consistent finite volume (FV) method has been applied to simulate the turbulent bluff-body reacting flows. To realistically account for the non-isotropic turbulence effects on the turbulent bluff-body reacting flows, the present PDF transport approach is based on the joint velocity- turbulent frequency-composition PDF formulation. The evolution of the fluctuating velocity of a particle is modeled by a simplified Langevin equation and the particle turbulence frequency is represented by the modified Jayesh - Pope model. Effects of molecular diffusion are represented by the interaction by exchange with the mean (IEM) mixing model. To validate this hybrid FV/PDF transport model, the numerical results are compared with experimental data for the turbulent bluff-body reacting flows.

• Parasites, Hosts and Diseases
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• 제37권4호
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• pp.197-213
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• 1999

Phylogeny is the evolutionary history of a group or the lineage of organisms and is reconstructed based on morphological, molecular and other characteristics. The genealogical relationship of a group of taxa is often expressed as a phylogenetic tree. The difficulty in categorizing the phylogeny is mainly due to the existence of frequent homoplasies that deceive observers. At the present time, cladistic analysis is believed to be one of the most effective methods of reconstructing a phylogenetic tree. Excellent computer program software for phylogenetic analysis is available. As an example, cladistic analysis was applied for nematode genera of the family Acuariidae, and the phylogenetic tree formed was compared with the system used currently. Nematodes in the genera Nippostrongylus and Heligmonoides were also analyzed, and the validity of the reconstructed phylogenetic trees was observed from a zoogeographical point of view. Some of the theories of parasite evolution were briefly reviewed as well. Coevolution of parasites and humans was discussed with special reference to the evolutionary relationship between Enterobius and primates.