• Title/Summary/Keyword: natural origin

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Search for Faint Quasars at z~5 using Medium-band Observations

  • Shin, Suhyun;Im, Myungshin;Kim, Yongjung;Hyun, Minhee;Jeon, Yiseul;Ji, Tae-Geun;Byeon, Seoyeon;Park, Woojin;Ahn, Hojae;Taak, Yoon Chan;Kim, Sophia;lim, Gu;Hwang, Sungyong;Paek, Insu;Paek, Gregory;Kim, Minjin;Kim, Dohyeong;Kim, Jae-Woo;Yoon, Yongmin;Choi, Changsu;Hong, Jueun;Jun, Hyunsung David;Karouzos, Marios;Kim, Duho;Kim, Ji Hoon;Lee, Seong-Kook;Pak, Soojong;Park, Won-Kee
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.2
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    • pp.36.2-36.2
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    • 2018
  • Cosmic reionization era in the early universe was playing a leading part on making the present universe we know. However, we have not been able to reveal the main contributor to the cosmic reionization to date. Faint quasars have been mentioned as the alternative due to the uncertainty of the faint end slope of the quasars luminosity function. With the availability of the deep (~25mag) images from Subaru Hyper Suprime-Cam (HSC) Strategic Program survey, we have tried to find more quasar with low luminosity in the ELAIS-N1 field. Faint quasar candidates were selected from several multi-band color cut criteria based on the track of the simulated quasar at z ~ 5. The Infrared Medium-deep Survey (IMS) and The UKIRT Infrared Deep Sky Survey (UKIDSS) - Deep Extragalactic Survey (DXS) provide J band information which is used to cover the relatively long wavelength range of quasar spectra. To search the reliable candidates with possible Lyman break, medium-band observation was performed by the SED camera for QUasars in EArly uNiverse(SQUEAN) in the McDonald observatory and Seoul National University 4k Camera(SNUCAM) in the Maidanak observatory. Photometric redshifts of the observed candidates were estimated from chi-square minimization. Also, we predicted the importance of the faint quasar to the cosmic reionization from the expected number density of the faint quasar.

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Use of natural ingredients in Japanese quail diet and their effect on carcass and meat quality - A review

  • Vargas-Sanchez, Rey David;Ibarra-Arias, Felix Joel;Torres-Martinez, Brisa del Mar;Sanchez-Escalante, Armida;Torrescano-Urrutia, Gaston Ramon
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.11
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    • pp.1641-1656
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    • 2019
  • The present paper reviews the findings of different research studies on the effect of natural ingredients in the Japanese quail (Coturnix coturnix japonica) diet on carcass characteristics and meat quality. The results show a relationship between the type and concentration of ingredients used in diets and carcass characteristics and meat quality. The inclusion of medicinal herbs (thyme, black seed, and mint), plants (canola), seeds (chickpea), spices (cinnamon and coriander), worms (earthworms), bee products (propolis), phytochemicals (lycopene), and edible fungi (common mushrooms) in the diet improved carcass quality characteristics compared to the control diets (basal diets). The inclusion of medicinal herbs (spearmint and green tea), spices (cinnamon), vegetables (tomato), plants (verbena and canola), seeds (marijuana), and edible fungi (oyster mushrooms) improved meat quality. In conclusion, the use of ingredients of natural origin in the diet of Japanese quail improves carcass quality characteristics and meat quality.

Visualization of the Origin of the Vertebral Arteries with Color Doppler Sonography (색도플러 초음파검사에 의한 경추골동맥 기시부 관찰)

  • Yoon, Seok-Hwan;Lee, Won-Hong;Lee, Dae-Hyung
    • Journal of radiological science and technology
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    • v.32 no.1
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    • pp.87-93
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    • 2009
  • Background/aim : Atherosclerotic disease at the origin of the vertebral arteries is one of the risk factors for vertebrobasilar ischemic disease. Assessment and visualization of the origin of the vertebral arteries with color doppler sonography is a non-trivial task. The aim of this study is to increase the visualization rate of the origin of the vertebral arteries with color doppler sonography. Materials and Methods : Color doppler sonography for the vertebral arteries included carotid arteries was performed to 198 patients. We first examined the vertebral artery in the upper neck in the direction of the subclavian artery to distinguish its origin more easily. If the vertebral artery origin was not visualized in natural position, the examiner pushed the transducer toward a clavicle or pushed the shoulder of patient by the other hand. The technical methods for visualization of the vertebral artery origin were classified into three grades: natural position, pushing the transducer, and pushing the shoulder of patient according to the depth (3.0 cm and shallower, deeper than 3.0 cm) of the origin. Results : The origin of the vertebral arteries could be visualized in 97% on the right and in 92% on the left. The origin of the vertebral arteries could be visualized in 98.6%, 1.4%, and 0.0% in natural position, pushing the transducer, and pushing the shoulder of patient, respectively, at shallower than 3.0 cm on the right side. The origin of the vertebral arteries could be visualized in 81.2%, 14.6%, and 4.2% in natural position, pushing the transducer, and pushing the shoulder of patient, respectively, at deeper than 3.0 cm on the right side. The origin of the vertebral arteries could be visualized in 85.4%, 10.7%, and 3.9% in natural position, pushing the transducer, and pushing the shoulder of patient, respectively, at shallower than 3.0 cm on the left side. The origin of the vertebral arteries could be visualized in 55.7%, 30.4%, and 13.9% in natural position, pushing the transducer, and pushing the shoulder of patient, respectively, at deeper than 3.0 cm on the left side. Conclusion : If the examiner pushes the transducer toward a clavicle or pushes the shoulder of patient by the other hand, when the vertebral artery origin during the color doppler sonography is not visualized in natural position, visualization rate of the origin of the both vertebral arteries is increased.

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Rousseauistic origin of Kant's theory of Freedom. (칸트 도덕철학의 자율적 자유 개념의 루소적 기원)

  • Moon, Sung-hak
    • Journal of Korean Philosophical Society
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    • v.116
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    • pp.79-110
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    • 2010
  • In this paper I will consider the Rousseauistic origin of Knat's theory of Freedom. Kant's autonomous freedom which is the main theme of the Critique of practical Reason have three characteristic elements, namely spontaneity, self-lawmaking and universal validity. Rousseau mentions three kinds of freedom in his works. Natural freedom which is treated in Discourse on the origin of inequality is freedom which a man in natural state have. I proved that natural freedom is the origin of Kant's theory of spontaneity that is a essential part of autonomous freedom. Social freedom which is treated in Social contract is deeply connected with general will. General will is the power of self-lawmaking. We can easily conclude that Rousseau's social freedom is the origin of Kant's theory of self-legislation which is another essential part of autonomous freedom. The last essential part of Kant's autonomous freedom is universality that is inseparably connected with Rousseau's moral freedom which is largely mentioned in Emlie.

Taxonomic Identity of Leaf Fragments Found in the Annals of the Joseon Dynasty and Botanical Origin of a Herbal Medicine 'Cheongung' (조선왕조실록 갈피에서 발견된 잎 조각의 실체 및 천궁의 식물학적 기원)

  • Suh, Youngbae;Kim, Yeong Sik;Lee, Chaemin;Park, Jisoo;Ko, Hye Jin;Lee, Sang Chan;Jeong, Jinsuk;Choi, Ho Young
    • Korean Journal of Pharmacognosy
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    • v.47 no.2
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    • pp.128-136
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    • 2016
  • Tiny leaf fragments were found in the Annals of the Joseon Dynasty, which were compiled about 500 years ago. The records describing the detailed process of compiling the Annals indicate that silk bags packed with the powders of 'Cheongung' and 'Changpo', which have been used as traditional herbal medicines in the northeast Asian countries such as China and Japan as well as Korea, were put in the wooden storage boxes together with the volumes of the Annals. However, there is no record that parts of plants were used in the process of compiling the Annals. The botanical origin of leaf fragments was identified as Ligusticum sinense 'Chuanxiong' by the analysis of trnK of chloroplast DNA as well as the examination of leaf surface with SEM. The comparative analysis of trnK sequences showed that the chloroplast DNA haplotype of 'Tocheongung', a triploid species cultivated in Korea, was identical with Cnidium officinale, but different from L. sinense 'Chuanxiong'. The molecular results provide a new suggestion on the botanical origin of crude drugs used as 'Cheongung', which has been disputed in Korea.

Survey of Faint Quasar candidates at 4.7 ≤ z ≤ 5.2

  • Shin, Suhyun;Im, Myungshin;Kim, Yongjung;Hyun, Minhee;Park, Woojin;Ji, Tae-geun;Jeon, Yiseul;Kim, Minjin;Kim, Dohyeong;Kim, Jae-Woo;Taak, Yoon Chan;Yoon, Yongmin;Choi, Changsu;Hong, Jueun;Jun, Hyunsung David;Karouzos, Marios;Kim, Duho;Kim, Ji Hoon;Lee, Seong-Kook;Pak, Soojong;Park, Won-Kee
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.1
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    • pp.59.4-60
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    • 2018
  • To investigate the impact of the high-redshift quasars on cosmic reionization, the faint end slope of the quasars luminosity function has to be determined precisely. More quasars with low luminosity are needed to constrain the contribution to reionization in the early universe. However, finding these quasars has been regarded as tough process owing to the improper shallow depth of imaging data. In recent days, the release data of Subaru Hyper Suprime-Cam (HSC) Strategic Program survey which provide the deep images reaching ~ 25 mag facilitates searching the faint quasars candidates. To find faint quasar candidates in ELAIS-N1 field, along with the HSC data, two near-infrared (NIR) data sets also be used : The Infrared Medium-deep Survey (IMS) and The UKIRT Infrared Deep Sky Survey (UKIDSS) - Deep Extragalactic Survey (DXS). Quasar candidates selected from the multi-band color cut were observed by the SED camera for QUasars in EArly uNiverse (SQUEAN) instrument. To trace the redshifted Lyman break efficiently, appropriate medium bands comparable to targeted redshift range are chosen. The most reliable quasar candidates are finally determined through SED fitting. Using this less luminous quasars candidates, we can speculate the relation between the quasar growth and the host galaxy unbiasedly and estimate the contribution to the cosmic reionization.

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Cloning of Autonomously Replicating Sequence from Phaffia rhodzyma

  • Chun, Soon Bai;Seung Hee Chun
    • Journal of Microbiology and Biotechnology
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    • v.5 no.6
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    • pp.370-372
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    • 1995
  • A Phaffia rhodozyma chromosomal fragment (approximately 3.8 kb) capable of functioning as an origin for the replication of a kanamycin resistance ($Km^r$) plasmid in S. cerevisiae was isolated by the use of origin search plasmid, pHN134. In S. cerevisiae, transformation frequencies using the plasmid pHN134 containing an autonomously replicating sequence of P. rhodozyma was 450-580 CFU/$\mu g$ DNA. The stability of the recombinant plasmid were 16-19$\%$.

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The Origins of Science and Technology Policy (과학기술정책의 기원)

  • 설성수
    • Journal of Technology Innovation
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    • v.5 no.1
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    • pp.113-149
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    • 1997
  • This paper, searching for the origin of the science and technology policy, is one of the research series on the original form of current S&T policy such as origin, evolution and changing patterns. Without understanding the origin, it is very difficult to understand the evolution and the current change of the policy. To answer this question, 2 kinds of conditions are set: 4 concepts for the origin of a policy and also 4 conditions for the S&T policy itself. As the origin of a policy, 4 concepts are set such as independence, continuance, diffusion and modern state as a policy body. Also as conditions for S&T policy, there may be 4 conditions such as policy targets, policy functions, administration body and the usage of the name of the policy. S&T can be distinguished as science, technology and S&T along it's development path. There, hence, are 2 origins of science and technology policy. French policy for modern science at the late 18th century and the establishment of the Agency of Science and Technology Policy of Japan in 1956 can be pointed out as the origin of the policy. The former can be called as the origin for natural science, and the latter as the origin for S&T. This study implies that new paradigm of S&T policy is a reflection for both the needs of new S&T and social needs. When there were big problems in a society and when there appeared new S&T, they exploited new S&T vigorously. This has been remained as a rememberable monuments in the history of the S&T policy.

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The Origin of the Metal-insulator Transitions in Non-stoichiometric TlCu3-xS2 and α-BaCu2-xS2

  • Jung, Dong-woon;Choi, Hyun-Guk;Kim, Han-jin
    • Bulletin of the Korean Chemical Society
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    • v.27 no.3
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    • pp.363-367
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    • 2006
  • The structure-property relations of ternary copper chalcogenides, $TlCu_{3-x}S_2$ and $\alpha-BaCu_{2-x}S_2$ are examined. The density of states, band dispersions, and Fermi surfaces of these compounds are investigated to verify the reason of the metal-insulator transitions by extended Huckel tight-binding band calculations. The origin of the metalinsulator transitions of non-stoichiometric $TlCu_{3-x}S_2$ and $\alpha-BaCu_{2-x}S_2$ is thought to be the electronic instability induced by their Fermi surface nesting.