• Title/Summary/Keyword: evolutionary status

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Selenium in Food Chain and Animal Nutrition: Lessons from Nature -Review-

  • Lyons, M.P.;Papazyan, T.T.;Surai, P.F.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.7
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    • pp.1135-1155
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    • 2007
  • Selenium is considered to be one of the most controversial trace elements. On the one hand, it is toxic at high doses and there is a great body of information related to environmental issues of Se contamination. On the other hand, Se deficiency is a global problem related to an increased susceptibility to various diseases of animals and humans and decreased productive and reproductive performance of farm animals. Optimisation of Se nutrition of poultry and farm animals will result in increased efficiency of egg, meat and milk production and even more important, will improve quality. From the data presented in the review it is clear that the main lesson which we have to learn from nature is how to use organic selenium in animal and human diets. Selenium-enriched yeast (Sel-Plex) is the result of such a lesson and it is just a matter of time before animal nutrition moves completely from using ineffective sodium selenite to organic selenium. Other lessons from nature will follow. Recent advances in genomics and proteomics, in association with descriptions of new selenoproteins, will be a driving force in reconsidering old approaches related to Se nutrition. Probably 90% of all Se research has been conducted with sodium selenite and we now understand that the natural form of selenium is different. The main advances in Se status assessment and Se requirements were established based on the activity of glutathione peroxidase (GSH-Px), an enzyme which for many years was considered to be the main selenoprotein. Recently it was discovered that it is only one of at least 25 various selenoproteins. Se research and practical applications are developing quickly and they are very exciting and promising.

LOW MASS RATIO CONTACT BINARY V410 Aur AND V776 Cas-II (질량비가 작은 접촉쌍성 V410 Aur과 V776 Cas-II)

  • Oh, Kyu-Dong;Kim, Chun-Hwey;Kim, Ho-il
    • Journal of Astronomy and Space Sciences
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    • v.22 no.3
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    • pp.223-232
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    • 2005
  • New BVR CCD light curves of the low mass ratio contact binaries, V410 Aur and V776 Cas, were observed with the 61 cm reflector and a 2K CCD camera at the Sobaeksan Astronomical Observatory. The absolute dimensions of the low mass ratio contact binaries, V410 Aur and V776 Cas, were obtained using WD program from the published spectroscopic and newly observed photometric data. The evolutionary status of this type of binary system including V410 Aur and V776 Cas has been considered. We reconfirmed that the primary stars of the low mass contact binary system were located on the TAMS and secondary stars were located under the ZAMS in H-R diagram.

LOW MASS RATIO CONTACT BINARY SYSTEMS HN UMa AND II UMa - III (질량비가 작은 접촉쌍성 HN UMa와 II UMa - III)

  • Lee Woo-Baik;Kim Ho-Il;Kang Young-Woon;Oh Kyu-Dong
    • Journal of Astronomy and Space Sciences
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    • v.23 no.3
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    • pp.189-198
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    • 2006
  • We present newly observed BVRI CCD light curves for low mass ratio contact binaries, HN UMa and II UMa. The absolute dimensions of these objects were obtained by applying the Wilson-Devinney program to previously published spectroscopic analysis and to our observed photometric data. The evolutionary status of all 21 low mass ratio contact binary system including HN UMa and II UMa was then considered. The secondaries of all low mass ratio contact binaries are located below the zero age main sequence in HR diagram. This phenomenon could be explained by mass loss from the secondary component in the low mass contact binary system because even small mass loss affects luminosity decrease in the low mass stars.

The Real Nature of "Chomskyan Revolution" ("촘스키혁명"의 실상)

  • Moon, Kyung-Hwan
    • Lingua Humanitatis
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    • v.8
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    • pp.175-198
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    • 2006
  • Quite a few historiographers of language science have measured the applicability of the term 'revolution' toward the line of work initiated by Chomsky, with the conclusion to the positive or negative effect as the case may be. This paper starts out with a brief review of this issue, with an interim conclusion that, while Chomskyan linguistics may be regarded as revolutionary in certain aspects, terms like 'revolution' and 'paradigm' are hardly applicable here in the way they were originally intended by Thomas Kuhn. It can be said, nontechnically, that the model of theory under discussion is at once 'revolutionary' and 'evolutionary' - in the sense that revolutions in linguistics have not resulted in abrupt loss of continuity with past 'paradigms', if there were any such. Chomsky's theory of language plays the same role of consolidation and refinement of structuralism that, say, the neogrmmarians played in their day. It has continued some fundamental traits of its predecessor, recovered others, and unwittingly rediscovered still others. But this is not the main thrust of the present paper. For, even if Chomskyan theory were to be looked upon as straightforwardly 'revolutionary', that revolution has not been a felicitous one. Some critic (Pieter A. M. Seuren, to be specific) goes as far as to say that "largely as a result of Chomsky's actions, linguistics is now sociologically in a very unhealthy state $\cdots$ to the point even of threatening to make that whole school of linguistics intellectually irrelevant." Besides, under the present state of language science that strikes one as typical of what Kuhn has characterized as "pre-paradigmatic" insecurity and disharmony, an unhealthy situation might take place if we were to think of the theoretical disagreements as conflicts between 'incommensurable' viewpoints-between 'rival paradigms' as it were-thereby avoiding or evading rational discussion. Another danger concerns the bandwagon effect, with linguists prematurely boarding each novel theory seemingly destined for popularity, for fear of being left clinging to an outdated 'paradigm.' Here lies another reason why the notion of 'revolution', Kuhnian or not, might as well be put aside, in the historiography of linguistics at the least.

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Spectropolarimetric Signals of Comet 2P/Encke During Its 2017 Apparition

  • Kwon, Yuna Grace;Ishiguro, Masateru;Kuroda, Daisuke;Kawabata, Koji S.;Nakaoka, Tatsuya;Kawabata, Miho;Uemura, Makoto;Shinnaka, Yoshiharu;Akitaya, Hiroshi;collaboration, OISTER
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.2
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    • pp.49.1-49.1
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    • 2017
  • Comets are one of the most primordial solar system objects that hold the information of the early days of solar system formation inside their nuclei. Orbiting the Sun, they spew such ancient materials that have been buried for many years, creating dust and gas comae. Cometary dust grains absorb and scatter sunlight radiating the continuous light, while gas molecules form the line emissions. Eachof the comets has its own light patterns, which depends on the physical and chemical properties of the dust and gas components. In this regard, spectropolarimetrycan be a powerful tool to study the properties of cometary constituents free from contamination of each other. This methodology offers a series of information on the polarization degrees of the dust and gas components as well as on wavelength dependence of the polarization degree and polarization angle of cometary dust simultaneously. Herein, we will report the results of the spectropolarimetric study of comet 2P/Encke, which is one of the well-known objects for its shortest orbital period and its prominent aging signals. We performed a spectropolarimetric observation of comet 2P/Encke in its inbound orbit using the Higashi-Hiroshima Optical and Near-Infrared Camera (HONIR) at the Higashi-Hiroshima Observatory, Japan, on UT 2017 February 21 at high phase angle of =75.7 deg. Ourstudy of this interesting comet is the first and only one done through spectropolarimetry in a referred publication. We will discuss the most recent polarimetric results of our study in terms of 2P/Encke' scurrent evolutionary status.

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Implementation of Virtual Diorama Using LEGO-Type 3D Brick System (레고유형의 3D 브릭 시스템을 활용한 가상 디오라마 구현)

  • Kwon, Hyo-Jeong;Jo, Hyun-Sin;Kim, Chee-Yong
    • Journal of Korea Multimedia Society
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    • v.9 no.10
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    • pp.1344-1353
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    • 2006
  • In terms of the product conforming to a social value of integration of digital and design, the importance of brick toys aiming at the convergence with digital technology in various ways has increased on the strength of expanded base of users and in pursuit of design innovation. Given that previous studies on bricks centered on the role as a tool of flay and education, it is true that studies on other indefinite potentials and expandability in light of multimedia have not been conducted. This study was initiated with a question how the brick system toys, which is gradually gaining popularity, has evolved and is aimed at examining the status of evolvement through study of basic theories and analysis of examples. Based on this, it is intended to explore the possibility of the digital brick system by executing design process utilizing examples of comprehensive brick system with expanded form.

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Review on the Educational Possibilities of The Virtual Museum as Online Learning Environments (온라인 학습환경으로서 가상박물관(Virtual Museum)의 가능성에 대한 탐구)

  • Kang, In-Ae;Seol, Yeon-Kyung
    • The Journal of the Korea Contents Association
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    • v.10 no.4
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    • pp.458-470
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    • 2010
  • As digital technologies have strongly impacted the whole social aspects, so museum recently emerging as an alternative or supplementary learning environment to school, after active adoption to the technologies, gave birth to museum websites called 'Virtual Museums' which, then, result in enhancing the educational roles and functions of physical museum. In this context, this study aimed to review the process of how virtual museum has been developed in terms of its educational roles and characteristics in accordance with the evolutionary development of web. Especially, the analysis of the status quo of the current virtual museums in both Korea and overseas presented specific aspects of the educational elements and roles embedded in virtual museum which have been emphasized in many related research and studies. The categories of the roles of the virtual museum, as a result, were classified into 'digital archive,' 'learning resources,' and 'communigy,' each of which were, then, further elaborated for its individual educational uses. Eventually this study purposed to expand the public awareness and knowledge of virtual museum as the alternative online learning environments needed in the 21st century.

Solar Photovoltaics Technology: No longer an Outlier

  • Kazmerski, Lawrence L.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.70-70
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    • 2011
  • The prospects of current and coming solar-photovoltaic (PV) technologies are envisioned, arguing this solar-electricity source is beyond a tipping point in the complex worldwide energy outlook. Truly, a revolution in both the technological advancements of solar PV and the deployment of this energy technology is underway; PV is no longer an outlier. The birth of modern photovoltaics (PV) traces only to the mid-1950s, with the Bell Telephone Laboratories' development of an efficient, single-crystal Si solar cell. Since then, Si has dominated the technology and the markets, from space through terrestrial applications. Recently, some significant shift toward technology diversity have taken place. Some focus of this presentation will be directed toward PV R&D and technology advances, with indications of the limitations and relative strengths of crystalline (Si and GaAs) and thin-film (a-Si:H, Si, Cu(In,Ga)(Se,S)2, CdTe). Recent advances, contributions, industry growth, and technological pathways for transformational now and near-term technologies (Si and primarily thin films) and status and forecasts for next-generation PV (nanotechnologies and non-conventional and "new-physics" approaches) are evaluated. The need for R&D accelerating the now and imminent (evolutionary) technologies balanced with work in mid-term (disruptive) approaches is highlighted. Moreover, technology progress and ownership for next generation solar PV mandates a balanced investment in research on longer-term (the revolution needs revolutionary approaches to sustain itself) technologies (quantum dots, multi-multijunctions, intermediate-band concepts, nanotubes, bio-inspired, thermophotonics, ${\ldots}$ and solar hydrogen) having high-risk, but extremely high performance and cost returns for our next generations of energy consumers. This presentation provides insights to the reasons for PV technology emergence, how these technologies have to be developed (an appreciation of the history of solar PV)-and where we can expect to be by this mid-21st century.

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The Function of Voice-over Narration in the Web-drama OH Ku-sil (웹드라마 <오구실>의 내레이션 기능 연구)

  • Ryu, Jae Hyung
    • The Journal of the Korea Contents Association
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    • v.18 no.6
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    • pp.399-413
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    • 2018
  • The purpose of this study is to find out the significance and functions of the voice-over narration in the storytelling of the web-drama OH Ku-sil. As a result, the first person narration has enhanced the intimacy with a viewer via subjective statements and produced the two time zone effect that the image and the voice-over stood on different tenses. On the other hand, the third person narration has expanded its functions beyond those of the cinema and TV drama. First, the third person narration in OH Ku-sil has performed the essential role presenting significant information for the viewer's understanding story. Second, the objective/authoritative statements of the third person narration have changed to the subjective/suggestive statements. Third, the third person narrator has expanded his/her role from a narrator to a virtual character by means of the comic statements. It seems to be the existing narration's effective response to the web-drama's medium characteristics seeking efficient storytelling under the tight time restriction. Delivering speedily the story information and amusement, this evolutionary voice-over narration is changing its status from the staying off subject to the condition of the new medium called web-drama.

Phylogenetic analysis of Neottia japonica (Orchidaceae) based on ITS and matK regions

  • SO, Ji-Hyeon;LEE, Nam-Sook
    • Korean Journal of Plant Taxonomy
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    • v.50 no.4
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    • pp.385-394
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    • 2020
  • To elucidate the molecular phylogeny of Neottia japonica, which is a terrestrial orchid distributed in East Asia, the internal transcribed spacer (ITS) of nuclear DNA and the matK of chloroplast DNA were used. A total 22 species of 69 accessions for ITS and 21 species of 114 accessions for matK phylogeny were analyzed with the maximum parsimony and Bayesian methods. In addition, we sought to establish a correlation between the distribution, morphology of the auricles and genetic association of N. japonica with phylogenetic data. The phylogenetic results suggest that N. japonica is monophyletic and a sister to N. suzukii in terms of the ITS phylogeny, while it is paraphyletic with N. suzukii in terms of the matK phylogeny. N. japonica and N. suzukii show similar morphologies of the lip and column, they both flower in April, and they are both distributed sympatrically in Taiwan. Therefore, it appears to be clear that N. japonica and N. suzukii are close taxa within Neottia, although there is incongruence between the nrDNA and cpDNA phylogenies of N. japonica. The incongruence between the two datasets may have various causes, meaning that further studies are needed to confirm the evolutionary process of N. japonica. The phylogenetic status of N. kiusiana, which was not included in previous studies, was as a sister to N. nidus-avis. Meanwhile, the ITS and matK phylogenies are unsuitable for identifying genetic associations with the characteristic of auricles. The phylogenetic topologies of Korean, Taiwanese and mainland Chinese individuals suggest that the populations of N. japonica in Korea originated from China's mainland and island areas. The characterization of regional gene differences could provide useful preliminary data for future studies.