• Title/Summary/Keyword: $^{14}C$ and $^{15}N$

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An Implementation of ATM Passive Optical Networks (PON) Based Cost Effective Optical Network Unit (ONU) (저가형 ATM-PON 광 액세스 시스템(ONU)의 구현)

  • Yang, C.Y.;Lee, D.C.;Jang, Y.S.;Hong, H.H;Moon, P.J.
    • Electronics and Telecommunications Trends
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    • v.15 no.1 s.61
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    • pp.1-14
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    • 2000
  • ATM PON 기반의 FTTH 광 정합 망은 향후 가장 효과적이고 경제적인 망이 될 것이므로 FTTC 망을 비용 경제적인 망으로 구현하기 위해서 광 액세스 시스템(ONU)을 최대한 저가격이고 소형이며 저전력을 소모하는 시스템으로 설계할 필요가 있다. 본 연구의 ONU는 FTTC/FTTH 기반의 155Mb/s(OC-3/STM-1) 및 622Mb/s(OC-12/STM-4) 속도의 ATM-PON 광 정합을 위한 광 액세스 시스템이다. 본 고에서는 유니버설 가입자 정합을 통하여 가입자에게 일반 및 공중전화, N-ISDN, 고속 인터넷 접속, 고속 멀티미디어 서비스 등의 다양한 서비스를 제공하기 위한 비용 효과적이고 소형이며 저전력을 소모하는 ONU 설계 및 구현방안을 기술하였다.

Palynological Study of Moojechi Bog (무제치늪의 화분분석 연구)

  • 최기룡
    • The Korean Journal of Quaternary Research
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    • v.15 no.1
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    • pp.13-20
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    • 2001
  • The Pollen analyses and the $^{14}C$-dating of the sediments of Moojechi bog were performed in order to study the vegetation history and the environmental changes of the southeasterm montane zone of Korea. These results show that the local pollen assemblage of the montane zone changed from lower upward cool-temperate northern/altimontane forest(MI) into cool-temperate central/montane forest(M II a) and cool-temperate souther $n_montane forest(M II b). Furthermore, In the case of the present cool temperature deciduous broad-leaved forests, its distribution would begin to be expanded from 8,000yr B.P., and its regional differentiation would be developed from 6,700yr B.P..P.

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Manufacture and Characterization of Low Firing Temperatur Substrate using Glass Ceramics with Fluorine (Fluorine 함유 Glass Ceramics를 이용한 저온 소결기판 제조 및 기판의 특성 평가)

  • 강원호
    • Journal of the Microelectronics and Packaging Society
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    • v.3 no.2
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    • pp.27-38
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    • 1996
  • Lithium fluorhectorite 결정상을 함유한 glass ceramics 분말의 형성과 제조된 glass ceramics 분말을 이용한 저온 소결기판의 특성평가를 하였다. Li2O-MgO-MgF2-SiO2 계 유 리로 핵형성 및 결정 성장을 실시하여 lithium fluorhectorite 결정상을 지닌 glass ceramics 를 제조하였다. 유리시편의 핵형성 온도는 46$0^{\circ}C$였고 결정성장온도는 600, 640, 110$0^{\circ}C$에서 나타났다. $600^{\circ}C$에서의 결정상으 Li2.4LiSi4O10F2가 나타났다. Li2.4Mg8LiSi4와 Li2.8Mg0.6SiO4은 lithium fluorhectorite 결정상으로 되기 위한 중간상임을 확인할수 있었다. 64$0^{\circ}C$에서 열처리 후 110$0^{\circ}C$에서 재열처리하여 형성된 결정은 lithium fluorhectorite 와 tridymite가 최종 결정 상으로 나타났다. 이것은 수중에서 water swelling 현상에 의하여 분말화할 수 있었다, 기판 제조용 slurry를 제조하기 위해 glass ceramics 분말에 Al2O3분말을 0,25,50wt%로 혼합한것 과 glass ceramics 분말에 potashborosilica-te glass 분말을 15, 30, 45, 60 wt% 로 배합하 여 doctor blade 법으로 green sheet를 제조하였다. green sheet 는 950~150$0^{\circ}C$로소성하여 기판의 특성을 평가하였다. 겉보기 기공율은 3.06~19,14%이었고, 전기적 특성으로 유전상수 는 3~5(100KHz)를 나타내었다.

Population Development of the Dinoflagellates Ceratium furca and Ceratium fusus during Spring and Early Summer in Iwa Harbor, Sagami Bay, Japan

  • Baek, Seung-Ho;Shimode, Shinji;Han, Myung-Soo;Kikuchi, Tomohiko
    • Ocean Science Journal
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    • v.43 no.1
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    • pp.49-59
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    • 2008
  • To examine the population development of the dinoflagellates, Ceratium furca and Ceratium fusus, daily field monitoring was conducted between April and July 2003 in the temperate coastal water of Sagami Bay, Japan. During the study period, the concentrations of C. furca were always lower than those of C. fusus. A sharp increase in the densities of both species was recorded on 5 May showing the maximum cell concentrations (C. furca = $14,800\;cells\;L^{-1}$, C. fusus = $49,600\;cells\;L^{-1}$). In the 7 days prior to the May bloom of the Ceratium species (29 April to 1 May), the highest density of the heterotrophic dinoflagellate Noctiluca scintillans was observed. Additionally, a second bloom of C. fusus occurred on 22 July. Here, two causes of the significant increases in the Ceratium populations during the two blooming periods (first time; 1 to 8 May, second time; 15 to 22 July) are presented. First, an increase in the nutrients of the surface layer regenerated by the breakdown of blooms by N.scintillans could be considered as a major cause of the population increase of the two Ceratium species. Second, a decrease in salinity (to 27 psu) was correlated with the later bloom of C. fusus. These results suggest that the population development of the two Ceratium species requires nutrients regenerated after the reduction of the diatom population by N. scintillans and, for C. fusus, continuous low salinity conditions, compared to other environmental factors during the rainy season.

Highly Active Analogs of α-Factor and Their Activities Against Saccharomyces cerevisiae

  • Ahn, Hee Jun;Hong, Eun Young;Jin, Dong Hoon;Hong, Nam Joo
    • Bulletin of the Korean Chemical Society
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    • v.35 no.5
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    • pp.1365-1374
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    • 2014
  • Thirteen analogs of tridecapeptide ${\alpha}$-factor (WHWLQLKPGQPMY) of Saccharomyces cerevisiae with C- or N-terminal Trp extension and isosteric replacement by Aib at position 8 and 11, Trp at position 13, D-Ala at position 9, and Orn and Glu at position 6 were synthesized and assayed for their biological activity. Receptor binding assay was carried out using our newly developed spectrophotometric method with detector peptide 14. C- or N-terminal extended analogs, ${\alpha}$-factor-$[Trp]_n$ (n =1-5) 1-5 and $[N-Trp]_1$-${\alpha}$-factor 6, were all less active than native ${\alpha}$-factor and gradual decreases in both activity and receptor affinity were observed with greater Trp extension. Trp-substituted analog at position 13, $[Trp^{13}]{\alpha}$-factor 7, exhibited about 2-fold reductions in both activity and receptor affinity. Aib-substituted analogs, $[Aib^8]{\alpha}$-factor 8 and $[Aib^{11}]{\alpha}$-factor 9, showed 5- to 10-fold reduction in activity as well as 3-fold reduction in receptor affinity compared to native ${\alpha}$-factor. $[Orn^6]{\alpha}$-factor 10 demonstrated strong potency with a 7.0-fold increase in halo activity as well as 1.8-fold increase in receptor affinity compared to native ${\alpha}$-factor. For two double substituted analogs, [$Glu^6,{\small{D}}-Ala^9$]${\alpha}$-factor 12 showed the slightly decreased potency in halo activity compared to analog 10, whereas [$Orn^6,{\small{D}}-Ala^9$]${\alpha}$-factor 11 exhibited 15-fold higher halo activity as well as nearly 3-fold higher receptor affinity compared to native ${\alpha}$-factor.

Chitosan and Acetylchitosan from Squid Pen and Their Characteristics (오징어 연골을 이용한 Chitosan 및 Acetylchitosan의 제조와 특성)

  • CHOI Hyeon-Mee;HWANG Sun-Young;PARK Seong-Min;LEE Keun-Tai
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.5
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    • pp.563-569
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    • 2001
  • In order to utilize the processing wastes of squid, chitosan was prepared by intermittent deacetylation treaoent of $\beta-chitin$ contained richly in the pen of squid. Acetylchitosan also was synthesized from squid pen chitosan with anhydrous acetic acid and their characteristics were investigated. The amounts of nitrogen and ash of squid pen chitosan were $5.80.2\% and 0.2\pm0.03\%$ respectively, the yield of squid pen chitosan was $25\pm3\%$, the degree of deacetylation was $92\%$, and the molecular weight was $1.15\times10^6$, Acetyl contents of N-acetylchitosan powder, acetylchitosan bead, N-ACF-1 (N-acetylchitosan film-1) and N-ACF-2 (N-acetylchitosan film-2) were $55.9\%, 63.2\%, 56\% and 58.7\%$ respectively. Two major peaks, amide I ($1,653 cm^{-1}$) and II ($1,558 cm^{-1}$) bent, on FT-IR spectra of the N-acetylchitosan from squid pen were almost similar to these of $\beta-chitin$, While there was a broad single peak at $1,601 cm^{-1}$assigned to be an amide I bend in squid pen chitosan. The CP/MAS NMR spectra of $\beta-chitin$, squid pen chitosan and N-acetylchitosan from squid pen showed a relative broad and single peak at 74 ppm assigned to fifth carbon (C-5) and third carbon (C-3). In case of $\beta-chitin$ and N-acetylchitosan from squid pen, single peak at 74 ppm was showed as the same of $\beta-chitin$ type.

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Purification and Characterization of Carotenoprotein from the Muscle of Ascidian, Halocynthia roretzi (우렁쉥이 육으로부터 Carotenoprotein의 분리.정제 및 특성)

  • Kang, Ok-Ju;Byun, Hee-Guk;Jeon, You-Jin;Kim, Jong-Bae;Kim, Se-Kwon
    • Applied Biological Chemistry
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    • v.41 no.1
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    • pp.31-41
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    • 1998
  • A carotenoprotein from the muscle of Ascidian (Halocynthia roretzi) was purified by ion exchange chromatography and gel filtration chromatography, and analyzed molecular weight, stability of pH and heat, effect of denaturing agents, amino acids and fatty acids composition. The purified carotenoprotein had absorption maxima of 463 nm and 439 nm. The carotenoprotein had an approxmimate molecular weight of 64.4 kDa in polyacrylamide gel electrophoresis. The amino acid compositions of carotenoprotein were mainly Gly (15.39%), Asn (11.31%), Gln (10.62%) and Ser (13.35%). The major fatty acids composition of carotenoprotein were $C_{16:1(n-7)}\;(15.4%)$, $C_{22:1(n-9)}\;(14.5%)$ and $C_{20:1(n-11)}\;(11.4%)$. The monounsaturated fatty acids (45.2%) contained abundant content compared to other saturated (38.1%) and polyunsaturated (11.7%) fatty acids.

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Spawning behavior and Morphological Development of the Eggs and Larvae of the Fringed blenny, Chirolophis japonicus from Korea (Pisces: Stichaeidae) (한국산 괴도라치 (Chirolophis japonicus)의 산란행동, 난 발생과 자어의 형태발달)

  • Park, Jae Min;Lee, Sung Hun;Choi, Jae Young;Han, Kyeong Ho
    • Korean Journal of Ichthyology
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    • v.27 no.2
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    • pp.63-70
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    • 2015
  • This research is about spawning behavior and morphological development of the eggs and larvae of fringed blenny which lives in Korean sea. It helps to find out the relation between fringed blenny larvae and other stichaeidae larva. Moreover, it is going to use for the basic data of taxonomical research. There were 8 mother fishes (total length 31.8~34.0 cm, average $32.9{\pm}0.21cm$), which were captured from the cost of Sindeok-dong, Yeosu-si, Jeollanam-do from December, 2010. we used trap to capture them. Mother fishes were brought to glass aquarium ($50{\times}30{\times}35cm$) and nurtured with recirculate rearing system. Breeding water temperature was $12.3{\sim}15.8^{\circ}C$ (average $14.1{\pm}2.47$) and salinity was 32.5~33.5‰ (average $33.0{\pm}0.05$‰). fertilized egg was round, opaque demersal egg. The size was 1.81~2.19 mm (average $2.00{\pm}0.27mm$, n=50). Incubation was begun after 271 hours and 30 minutes from fertilization. It started with piercing the egg membrane. prelarvae had length of 8.45~8.84 mm (average $8.65{\pm}0.28mm$, n=5) right after the incubation, and both mouth and anus were opened. After 11 days from the incubation, postlarvae had length of 10.5~11.3 mm (average $10.9{\pm}0.57mm$), and the number of myotomes was increased to 66.

Cytogenetic and Genetic Mutation Features of de novo Acute Myeloid Leukemia in Elderly Chinese Patients

  • Su, Long;Li, Xian;Gao, Su-Jun;Yu, Ping;Liu, Xiao-Liang;Tan, Ye-Hui;Liu, Ying-Min
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.2
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    • pp.895-898
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    • 2014
  • Objectives: The present study aimed to examine the cytogenetic and genetic mutation features of acute myeloid leukemia (AML) in elderly Chinese patients. Methods: A retrospective analysis of cytogenetics and genetic mutations was performed in 113 cases (age range 50-82 years) with de novo AML. Results: The most frequent cytogenetic abnormality was t (15;17) (q22;q21), detected in 10.0% (n = 9) of successfully analyzed cases, followed by t (8;21) (q22;q22) in 8.89% (n = 8), and complex karyotypes in 5.56% (n = 5). Those with complex karyotypes included 4 cases (4.44%) of monosomal karyotypes. The frequencies of NPM1, FLT3-ITD, c-kit, and CEBPA mutations were 27.4% (31/113), 14.5% (16/110), 5.88% (6/102), and 23.3% (7/30), respectively. The complete remission rates of patients in low, intermediate, and high risk groups were 37.5%, 48.6%, and 33.3%, respectively (${\chi}^2$ = 0.704, P = 0.703) based on risk stratification. Conclusion: Cytogenetics and genetic mutations alone may not be sufficient to evaluate the prognoses of elderly AML patients. The search for a novel model that would enable a more comprehensive evaluation of this population is therefore imperative.

Effects of Aging and Soil Texture on Composting of Diesel-Contaminated Soil (디젤오염기간 및 토성이 오염토양 콤포스팅 처리에 미치는 영향)

  • Choi, Jung-Young;Namkoong, Wan;Park, Joon-Seok;Hwang, Eui-Young
    • Journal of the Korea Organic Resources Recycling Association
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    • v.10 no.2
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    • pp.132-139
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    • 2002
  • This study was carried out to investigate the effects of aging and soil texture on composting of diesel-contaminated soil. The soils used for this study were silt loam and sand. Target contaminant, diesel oil, was spiked at 10,000mgTPH/kg of dry soil. Aging times of diesel-contaminated soils were 15days and 60days, respectively. Fresh diesel-contaminated soil was also investigated. Moisture content was controlled to 70% of soil field capacity. Mix ratio of soil to sludge was 1:0.3 as wet weight basis. Temperature was maintained at $20^{\circ}C$ Volatilization loss of TPH was below 2% of initial concentration. n-Alkanes lost by volatilization were mainly by the compounds of C10 to C17. Diesel in contaminated soil was mainly removed by biodegradation mechanism. First order degradation rate constant of TPH in sandy soil was ranged from 0.081 to 0.094/day, which is higher than that in silt loam(0.056-0.061/day). From fresh to 60day-aged soils, there was little difference of TPH biodegradation rate between the soils. Carbon recovery ranged from 0.61 to 0.89. TPH degradation rate was highly correlated with $CO_2$ production rate.

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