• Title/Summary/Keyword: d.c field

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Hydration Effect on the Intrinsic Magnetism of Natural Deoxyribonucleic Acid as Studied by EMR Spectroscopy and SQUID Measurements

  • Kwon, Young-Wan;Lee, Chang-Hoon;Do, Eui-Doo;Choi, Dong-Hoon;Jin, Jung-Il;Kang, Jun-Sung;Koh, Eui-Kwan
    • Bulletin of the Korean Chemical Society
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    • v.29 no.6
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    • pp.1233-1242
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    • 2008
  • The hydration effect on the intrinsic magnetism of natural salmon double-strand DNA was explored using electron magnetic resonance (EMR) spectroscopy and superconducting quantum interference device (SQUID) magnetic measurements. We learned from this study that the magnetic properties of DNA are roughly classified into two distinct groups depending on their water content: One group is of higher water content in the range of 2.6-24 water molecules per nucleotide (wpn), where all the EMR parameters and SQUID susceptibilities are dominated by spin species experiencing quasi one-dimensional diffusive motion and are independent of the water content. The other group is of lower water content in the range of 1.4-0.5 wpn. In this group, the magnetic properties are most probably dominated by cyclotron motion of spin species along the helical π -way, which is possible when the momentum scattering time (${\tau}_k$) is long enough not only to satisfy the cyclotron resonance condition (${\omega}_c{\tau}_k$ > 1) but also to induce a constructive interference between the neighboring double helices. The same effect is reflected in the S-shaped magnetization-magnetic field strength (M-H) curves superimposed with the linear background obtained by SQUID measurements, which leads to larger susceptibilities at 1000 G when compared with the values at 10,000 G. In particular, we propose that the spin-orbital coupling and Faraday's mutual inductive effect can be utilized to interpret the dimensional crossover of spin motions from quasi 1D in the hydrate state to 3D in the dry state of dsDNA.

Effect of Carthami Tinctorii Fructus Herbal-acupuncture Solution(CTF-HAS) on Gene Expression in HepG2 carcinomar cells by Proteomic Analysis (Proteomic Analysis기법을 이용한 홍화자약침액(紅花子藥鍼液)이 간암세포주(肝巖細胞柱)의 유전자(遺傳子) 발현(發顯)에 미치는 영향(影響))

  • Lee, Kyung-Min;Lim, Seong-Chul;Jeong, Tae-Young;Seo, Jung-Chul;Han, Sang-Won
    • Journal of Pharmacopuncture
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    • v.8 no.2
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    • pp.23-28
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    • 2005
  • Objective : It has long been known about the osteogenic effect of CTF-HAS on bone tissues. However, it has not been determined the effect of CTF-HAS on cancer cells. The purpose of this study is to screen the CTF-HAS mediated differentially expressed genes in cancer cells such as HepG2 hepatoma cells lines. Methods : CTF-HAS was prepared by boiling and stored at $-70^{\circ}C$ until use. For proteomic analysis, total protein was analyzed by 2D gel electrophoresis and Q-TOF mass spectrometer. Results : In proteomic analysis, three spots were identified by 2D-gel electrophoresis and Q-TOF analysis. One down-regulated protein was heat shock 70kDa protein 5 and up-regulated proteins were chaperonin and 2-phospho -pyruvate-hydratase ${\alpha}-enolase$ by 1.5mg/ml of CTF-HAS. Discussion : Proteomic analysis approach were performed to screen the differential expression genes. The screened genes will be used for the better understanding in therapeutic effect of CTF-HAS on cancer field.

Design of high speed InAlGaAs/InGaAs HBT structure by Hybrid Monte Carlo Simulation (Hybrid Monte Carlo 시뮬레이션에 의한 고속 InAlGaAs/InGaAs HBT의 구조 설계)

  • 황성범;김용규;송정근;홍창희
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.36D no.3
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    • pp.66-74
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    • 1999
  • InAlGaAs/InGaAs HBTs with the various emitter junction gradings(xf=0.0-1.0) and the modified collector structures (collector- I;n-p-n, collector-II;i-p-n) are simulated and analyzed by HMC (Hybrid Monte Carlo) method in order to find an optimum structure for the shortest transit time. A minimum base transit time($ au$b) of 0.21ps was obtainsed for HBT with the grading layer, which is parabolically graded from $x_f$=1.0 and xf=0.5 at the emitter-base interface. The minimum collector transit time($\tau$c) of 0.31ps was found when the collector was modified by inserting p-p-n layers, because p layer makes it possible to relax the electric field in the i-type collector layer, confining the electrons in the $\Gamma$-valley during transporting across the collector. Thus InAlGaAs/InGaAs HBT in combination with the emitter grading($x_f$=0.5) and the modified collector-III showed the transit times of 0.87 psec and the cut-off frequency (f$\tau$) of 183 GHz.

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Development of a Rapeseed Seeder Attached to Tractors (트랙터 부착용 유채파종기 개발)

  • Lee, C.K.;Choi, Y.;Jun, H.J.;Choi, D.K.;Kim, Y.J.;Lee, S.K.;Moon, S.D.;Han, B.H.
    • Journal of Biosystems Engineering
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    • v.34 no.3
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    • pp.147-154
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    • 2009
  • Suitable rapeseed cultivation techniques of domestic agriculture are essential for stable security, supply and demand of rapeseed. This research developed a rapeseed seeder for bio-diesel and analyzed the seeding performance improving an existent granule fertilizer applicator. The relational expression of metering groove size and discharge rate per time displayed high correlation with a coefficient of determination of 0.988. Also, the scattering types were analyzed by forwarding speed and discharge rate. Validity application width was decided as 7.0 m by analyzing application uniformity at application widths of 7.6 m, 6.6 m, 5.6 m. All average coefficients of variation values were less than 20%. The best application uniformity was obtained in the condition of a work speed of 1.3 m/s and a sowing rate of 19.0 g/s. It was better average coefficient of variation values under 10% at superposition application of rapeseed seeder. Also, scattering amount rates of right and left were within 0.89${\sim}$1.0.

A Study on the Piezoelectric Characteristics of Ca-Substituded $PbTiO_3$ Ceramics (Ca가 치환된 $PbTiO_3$계 세라믹스의 압전 특성에 관한 연구)

  • Park, J.H.;Yoon, S.J.;Lee, D.H.;Paik, D.S.;Park, C.Y.
    • Proceedings of the KIEE Conference
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    • 1992.07b
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    • pp.744-746
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    • 1992
  • In this study, we investigated structural, electrical characteristics and studied the conditions which improved hydrostatic constants in hydrophones as we changed x = 0.1, 0.25, 0.35, 0.4 and y = 0.04, 0.08, 0.12, 0.16 in $(Pb_{1-x}Ca_x)[(Mg_{1/3}Nb_{2/3})_yTi_{1-0.01}Mn_{0.01}]O_3$ ceramics in which Ca was substituted with Pb and $Pb(Mg_{1/3}Nb_{2/3})O_3$ was added to decrease sintering temperature in $PbTiO_3$. When Ca was substituted 0.25[mol], the largest electro-mechanical anisotropy ($k_t/k_p$) was found ($k_t{\fallingdotseq}50,k_p{\fallingdotseq}4$), and the less $Pb(Mg_{1/3}Nb_{2/3})O_3$ and the stronger poling field, the larger this anisotropy was. When Ca=0.25[mol], $Pb(Mg_{1/3}Nb_{2/3})O_3=0.08[mol]$ were substituted, ($k_t/k_p$)(=12, 3) was large, permittivity was low and hydrostatic constants were high. Therefore, this composition is promising as wide band ultrasonic devices in water.

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Video Production Method using Match Moving Technique (매치무빙 기법을 활용한 모션그래픽 영상제작에 관한 연구)

  • Lee, Junsang;Park, Junhong;Lee, Imgeun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.4
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    • pp.755-762
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    • 2016
  • Motion graphic is the recently emerged technique which extends the ways of expression in video industry. Currently, it is worldwide trends that the image design gets more attention in the field of movie, advertisement, exhibition, web, mobile, games and new media, etc. With the development of computer's new technologies, VFX methods for the visual content is dynamically changed. Such production methods combine the real scenary and CG(Computer Graphic) to compose realistic scenes, which cannot be pictured in the ways of ordinary filming. This methods overcome the difference between the real and virtual world, maximize the expressive ways in graphics and real space. Match moving is technique of accurate matching between real and virtual camera to provide realistic scene. In this paper we propose the novel technique for motion graphic image production. In this framework we utilize the match moving methods to get the movements of the real camera into 3D layer data.

Growth of Non-Polar a-plane ZnO Layer On R-plane (1-102) Sapphire Substrate by Hydrothermal Synthesis (저온 수열 합성법에 의해 (1-102) 사파이어 기판상에 성장된 무분극 ZnO Layer 에 관한 연구)

  • Jang, Jooil;Oh, Tae-Seong;Ha, Jun-Seok
    • Journal of the Microelectronics and Packaging Society
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    • v.21 no.4
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    • pp.45-49
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    • 2014
  • In this study, we grew non-polar ZnO nanostructure on (1-102) R-plane sapphire substrates. As for growth method of ZnO, we used hydrothermal synthesis which is known to have the advantages of low cost and easy process. For growth of non-polar, the deposited AZO seed buffer layer with of 80 nm on R-plane sapphire by radio frequency magnetron sputter was annealed by RTA(rapid thermal annealing) in the argon atmosphere. After that, we grew ZnO nanostructure on AZO seed layer by the added hexamethylenetramine (HMT) solution and sodium citrate at $90^{\circ}C$. With two types of additives into solution, we investigated the structures and shapes of ZnO nanorods. Also, we investigate the possibility of formation of 2D non-polar ZnO layer by changing the ratio of two additives. As a result, we could get the non-polar A-plane ZnO layer with well optimized additives' concentrations.

A Review of Recent Developments in Buffalo Reproduction - A Review

  • Warriach, H.M.;McGill, D.M.;Bush, R.D.;Wynn, P.C.;Chohan, K.R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.3
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    • pp.451-455
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    • 2015
  • The buffalo is an important livestock resource in several countries of South Asia and the Mediterranean regions. However, reproductive efficiency is compromised due to known problems of biological and management origins, such as lack of animal selection and poor nutrition. Under optimal conditions puberty is attained at 15 to 18 months in river buffalo, 21 to 24 months in swamp buffalo and is influenced by genotype, nutrition, management and climate. However, under field conditions these values deteriorate up to a significant extant. To improve reproductive efficiency, several protocols of oestrus and ovulation synchronization have been adopted from their use in commercial cattle production. These protocols yield encouraging pregnancy rates of (30% to 50%), which are comparable to those achieved in buffaloes bred at natural oestrus. The use of sexed semen in buffalo heifers also showed promising pregnancy rates (50%) when compared with conventional non-sexed semen. Assisted reproductive technologies have been transferred and adapted to buffalo but the efficiency of these technologies are low. However, these latest technologies offer the opportunity to accelerate the genetic gain in the buffalo industry after improving the technology and reducing its cost. Most buffaloes are kept under the small holder farming system in developing countries. Hence, future research should focus on simple, adoptable and impact-oriented approaches which identify the factors determining low fertility and oestrus behaviour in this species. Furthermore, role of kisspeptin needs to be explored in buffalo.

Paleomagnetic Study of the Yeonil Group in Pohang Basin (포항분지(浦港盆地)에 분포(分布)하는 연일층군(延日層群)의 고지자기(古地磁氣) 연구(硏究))

  • Kim, Kwang Ho;Doh, Seong-Jae;Hwang, Chang-Soo;Lim, Dong Seong
    • Economic and Environmental Geology
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    • v.26 no.4
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    • pp.507-518
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    • 1993
  • Paleomagnetic investigations have been carried out on the Tertiary sedimentary formations (Yeonil Group) in Pohang basin, southeastern Korea. A total of 215 samples were collected from 26 sites. Progressive thermal demagnetization indicates that many samples have unstable magnetization and do not reveal a characteristic direction. However, some samples from the lower and upper Duho Formation show a characteristic direction $D/I=7.8^{\circ}/48.3^{\circ}$ (${\alpha}_{95}=3.7^{\circ}$, k=174.1). Stepwise thermal demagnetization data show that some samples from the Hagjeon and middle Duho Formations reveal great-circle distributions moving from the present to a reversed direction of geomagnetic field. The mean of intersection points of the great-circles is nearly antipodal to the characteristic normal direction of the lower and upper Duho Formation. We infer that the Hagjeon Formation was formed during the reversed polarity chron C5B (16.2~14.7 Ma) and the Duho Formation 14.7~11.6 Ma based on our results and previous paleontologic and age dating data. Paleomagnetic direction for the Middle Miocene of Korea, analysed from the combined results of stable endpoints and great circles, is $D/I=8.7^{\circ}/53.9^{\circ}$ (${\alpha}_{95}=4.2^{\circ}$, k=74.8), and the corresponding paleopole is Lat./Long.=$82.7^{\circ}/230.2^{\circ}$ (${\delta}p=2.8^{\circ}$, ${\delta}m=5.9^{\circ}$). On the basis of this, we interpret that the opening of the East sea (Japan sea) or the synchronous clockwise rotation of the Southwest Japan exerted no structural influence on the Yeonil Group in the Middle Miocene.

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TOWARD A NEXT GENERATION SOLAR CORONAGRAPH: DEVELOPMENT OF A COMPACT DIAGNOSTIC CORONAGRAPH FOR THE ISS

  • Cho, K.S.;Bong, S.C.;Choi, S.;Yang, H.;Kim, J.;Baek, J.H.;Park, J.;Lim, E.K.;Kim, R.S.;Kim, S.;Kim, Y.H.;Park, Y.D.;Clarke, S.W.;Davila, J.M.;Gopalswamy, N.;Nakariakov, V.M.;Li, B.;Pinto, R.F.
    • Journal of The Korean Astronomical Society
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    • v.50 no.5
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    • pp.139-149
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    • 2017
  • The Korea Astronomy and Space Science Institute plans to develop a coronagraph in collaboration with National Aeronautics and Space Administration (NASA) and to install it on the International Space Station (ISS). The coronagraph is an externally occulted one-stage coronagraph with a field of view from 3 to 15 solar radii. The observation wavelength is approximately 400 nm, where strong Fraunhofer absorption lines from the photosphere experience thermal broadening and Doppler shift through scattering by coronal electrons. Photometric filter observations around this band enable the estimation of 2D electron temperature and electron velocity distribution in the corona. Together with a high time cadence (<12 min) of corona images used to determine the geometric and kinematic parameters of coronal mass ejections, the coronagraph will yield the spatial distribution of electron density by measuring the polarized brightness. For the purpose of technical demonstration, we intend to observe the total solar eclipse in August 2017 with the filter system and to perform a stratospheric balloon experiment in 2019 with the engineering model of the coronagraph. The coronagraph is planned to be installed on the ISS in 2021 for addressing a number of questions (e.g., coronal heating and solar wind acceleration) that are both fundamental and practically important in the physics of the solar corona and of the heliosphere.