• 제목/요약/키워드: Molecular evolution

검색결과 529건 처리시간 0.035초

PLANETARY NEBULAE: NEW CHALLENGES IN THE 21ST CENTURY

  • KWOK SUN
    • 천문학회지
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    • 제38권2호
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    • pp.271-278
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    • 2005
  • Athough planetary nebulae (PNe) have been discovered for over 200 years, it was not until 30 years ago that we arrived at a basic understanding of their origin and evolution. Even today, with observations covering the entire electromagnetic spectrum from radio to X-ray, there are still many unanswered questions on their structure and morphology. In this review, we summarize recent theoretical and observational advances in PNe research, and discuss the roles of PNe in the chemical (atomic, molecular, and solid-state) enrichment of the galaxy and as tracers of the large scale structure of the Universe.

Plant Defense Responses Coming To Shape

  • Kwon, Chi-An
    • The Plant Pathology Journal
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    • 제26권2호
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    • pp.115-120
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    • 2010
  • Although still poorly understood, accumulating evidence clearly supports that plants also have a good immune system which have been developed and acquired during the evolution. The lack of specific mobile immune cells like a B or T cell in plants additionally suggests that most plant cells have capacity for defending themselves against numerous pathogens. Rapidly growing advances in understanding plant defense responses implicate that plant and animal immune responses are evolutionarily convergent although their origins are thought to be different. On the basis of recent findings, here current understanding of plant defense responses will be discussed.

Extragalactic Science with ALMA: First Results & Future Perspectives

  • Chung, Aeree
    • 천문학회보
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    • 제39권2호
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    • pp.118.2-118.2
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    • 2014
  • As the most sensitive radio interferometer ever operated in millimeter/submillimeter, the ALMA has opened a new window on extragalactic astronomy. Its superior resolution and sensitivity allow the community to study the gas kinematics of distant galaxies as well as the molecular gas properties of nearby galaxies in GMC scale, already in its early commissioning stage. Also the ALMA provides a great tool to probe the dust contents of extragalactic sources at all redshifts, which is important in understanding of galaxy formation and evolution history over cosmic time. In this presentation, I will review the ALMA capabilities with the emphasis on the extragalactic science. I will also revisit some highlights from the early science and discuss future perspectives.

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심근 SPECT를 이용한 관상동맥질환의 진단 (Diagnosis of Coronary Artery Disease Using Myocardial Perfusion SPECT)

  • 원경숙;김해원
    • Nuclear Medicine and Molecular Imaging
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    • 제43권3호
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    • pp.196-202
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    • 2009
  • Myocardial perfusion scintigraphy is currently by far the most commonly performed cardiac nuclear study, constituting approximately one third of all nuclear medicine procedure. It plays an important role in the diagnosis, prognosis, risk assessment and management of heart disease. Aim of this review is to describe recent evolution of myocardial perfusion imaging on the focus of diagnosis of coronary artery disease. In addition, current status of other imaging modalities will be reviewed.

Three Aetideid Species of Copepods (Copepoda: Calanoida: Aetideidae) from East Sea of Korea

  • Lim, Byung-Jin;Song, Sung-Joon;Min, Gi-Sik
    • Animal Systematics, Evolution and Diversity
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    • 제27권1호
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    • pp.35-46
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    • 2011
  • Three aetideid copepods collected from the East Sea of Korea are described: Bradyidius angustus (Tanaka, 1957), Gaetanus minutus (Sars, 1907), and Aetideus acutus Farran, 1929. The former two species are new to the Korean copepod fauna. The sequences of cytochrome c oxidase subunit 1 were determined to be the molecular characteristics of these three species.

Two New Eisenia Species from South Korea Similar to E. koreana and Comparable to Eisenoides from USA (Oligochaeta: Lumbricidae)

  • Blakemore, Robert J.;Park, Tae Seo
    • Animal Systematics, Evolution and Diversity
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    • 제28권4호
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    • pp.297-303
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    • 2012
  • New Korean lumbricids are described: Eisenia gaga Blakemore sp. nov. from remote Gageodo Island and E. sindo Blakemore, sp. nov. from an island at Incheon. Both are comparable to Eisenia koreana (Zicsi, 1972) from near Pyongyang, North Korea. A remarkable yet previously unrecognized similarity to American earthworm Eisenoides carolinensis (Michaelsen, 1910) is discussed, but synonymy is rejected on tenuous morphological grounds (form of nephridial vesicle bladders) with taxonomy supported by objective molecular data (mtDNA cytochrome c oxidase subunit 1 barcodes).

Molecularr Analysis of $\alpha$-Glucosidase from Microorganism

  • Kimura, Atsuo
    • 한국미생물생명공학회:학술대회논문집
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    • 한국미생물생명공학회 2001년도 Proceedings of 2001 International Symposium
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    • pp.73-76
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    • 2001
  • $\alpha$-Glucosidase contributing $\alpha$-glucan metabolism in microorganisms is characterized by the variety in substrate recognition. Recent studies on microbial enzymes show that $\alpha$-glucosidases are divided into two groups, family I and family n, in which family I enzymes have four conserved catalytic-regions of $\alpha$-amylase family. The presentation focusing on the difference of the $\alpha$-glucosidase families reviews i) the catalytic amino-acid residues of nucleophile and acid/base catalyst, and ii) the molecular evolution of two families.

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Introduction of Phylodynamics for Controlling the HIV/AIDS Epidemic in Korea

  • Bae, Jong-Myon
    • Journal of Preventive Medicine and Public Health
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    • 제51권6호
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    • pp.326-328
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    • 2018
  • As over 1000 new cases of HIV/AIDS occur in Korea annually, preventive health programs against HIV/AIDS are urgently needed. Since phylodynamic studies have been suggested as a way to understand how infectious diseases are transmitted and evolve, phylodynamic inferences can be a useful tool for HIV/AIDS research. In particular, phylodynamic models are helpful for dating the origins of an epidemic and estimating its basic reproduction number. Thus, the introduction of phylodynamics would be a highly valuable step towards controlling the HIV/AIDS epidemic in Korea.

Towards the Understanding of the Growth and Evolution of Supermassive Black Holes at Galaxy Centers

  • Kim, Ji-hoon
    • 천문학회보
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    • 제43권2호
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    • pp.32.2-32.2
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    • 2018
  • As computational resolution of modern cosmological simulations reach ever so close to resolve individual star-forming clumps in a galaxy, a need for "resolution-appropriate" physics for a galaxy-scale simulation has never been greater. To this end, we introduce a self-consistent numerical framework that includes explicit treatments of feedback from star-forming molecular clouds and massive black holes. We perform a state-of-the-art cosmological simulation of a quasar-host galaxy at z~7.5, and demonstrate that previously undiscussed types of interplay between galactic components may hold important clues about the growth and impact of quasar-host galaxies.

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