• Title/Summary/Keyword: GCA

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Production and Separation of Cystocin from Streptomyces sp GCA0001 (Streptomyces sp GCA0001로부터 Cystocin의 생산 및 분리 정제)

  • 김동현;이희찬;우진석;송재경;류광경;김대희;강선엽
    • Proceedings of the KAIS Fall Conference
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    • 2001.05a
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    • pp.292-294
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    • 2001
  • Cystocin is identified from the screening of Streptomyces sp GCA0001. It is isolated from the culture of streptomyces sp GCA0001. A white coloured cystocin is structurally similar to puromycin, an antibiotic produced by streptomyces albonrger. Like puromycin, cystocin possesses an antibacterial, antitumour and antiviral activity. It impairs the protein synthesis by inhibiting polypeptide chain elongation.

GCA Reconstruction Algorithm within the EM model for Transmission Computed Tomography (투과형 CT를 위한 EM 모형하에서 GCA 재구성 알고리즘)

  • 김승구
    • The Korean Journal of Applied Statistics
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    • v.12 no.2
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    • pp.537-551
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    • 1999
  • 방출형 토모그래피와는 다르게, 토과형 토모그래피를 위한 통계적 알고리즘들은 매우 늦은 수렴속도와 엄청난 계산시간을 감수해야 했다. 그 주된 이유는 Lange-Carson 모형에 기초한 EM 알고리즘을 사용하고 있기 때문인데, 최근 GCA 기법의 등장으로 계산 시간을 현저히 단축할 수 있는 가능성이 제공되었다. 그러나 GCA 알고리즘은 우도의 단조중가성을 만족시키기 위해 부가적인 계산시간을 희생해야만 한다. 이에 본 연구에서는 프로그래밍이 간편하며, 처리시간이 짧고, 자체로 우도의 단조증가성을 만족하는 투과형 토모그래피를 위한 재구성 알고리즘을 제안한다.

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Radioautographical observations of development and appearance of glia cells in brain I. Apperarace of ectodermal glial cell aggregates in rodent brain (뇌신경교세포(腦神經膠細胞) 집단(集團)의 발생(發生)과 이동(移動)에 대한 방사선(放射線) 자기법적(自記法的) 관찰 I, 설치류 뇌(腦)에 외배엽성(外胚葉性) 신경교세포(神經膠細胞) 집단(集團)의 출현(出現)에 대하여)

  • Kwak, Soo-dong
    • Korean Journal of Veterinary Research
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    • v.32 no.4
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    • pp.481-487
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    • 1992
  • The present study was designed to investigate the appearance of the congenital aggregates of the ectodermal glial cells in the brain of the normal rodents. The brain samples were taken from mice fetus, juvenile mice, rats and rabbits. The appearance regions of the glial cell aggregates (GCA) were investigated and the cells in the GCA were identified with electron microscope. 1. GCA in the mouse fetus tended to be higher in cell density, larger in size and lower frequency in appearance than juvenile mouse. The regions of higher appearance frequency of GCA in the juveniles of mice, rats and rabbits were ordered as subependymal layer in the collateral trigone of lateral ventricles, molecular layer of the neocortex, inner layer except the molecular layer in the neocortex, cerebral medulla, corpus callosum and hippocampus. Appearance frequency of GCA in the neonatal mice tended to be higher until 5 day after birth, and were markedly decreased on 10 and 15 day after birth. 2. GCA tended to be closed on one side of the blood vessels or neurons but not perivascular or perineuronal appearance. 3. In electron microscophy, GCA were composed of immature oligodendrocytes and astrocytes in the subependymal, and tended to be more mature and loose in the neocortex and to be appended some microglia cells with age. The cells in the GCA of older mice tended to be more mature than in young mice.

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Structure Analysis, Biological Activity of a Novel Antibiotics, Cystocin, from Streptomyces sp. GCA0001 and Production of its Derivatives (Streptomyces sp. GCA0001로부터의 신규 항생물질 Cystocin의 구조분석, 생물활성 및 유도체제조)

  • 김자용;이희찬;우진석;송재경
    • Proceedings of the KAIS Fall Conference
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    • 2001.05a
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    • pp.295-297
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    • 2001
  • Cystocin, a derivative of Puromycin, is a new material derived from Streptomyces sp GCA0001, new strain of Actinomycetes spiecies. This compound has outstanding biological activities in anti-bacteria, anti-tumor and anti-virus than former Puromycin compounds. And it is chosen by natural selection processing through extraction, isolation and purification from , so it may replace old Puromycins in most applications.

Effect of relative density on the shear behaviour of granulated coal ash

  • Yoshimoto, Norimasa;Wu, Yang;Hyodo, Masayuki;Nakata, Yukio
    • Geomechanics and Engineering
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    • v.10 no.2
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    • pp.207-224
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    • 2016
  • Granulated coal ash (GCA), a mixture of the by-product from milling processes with a small amount of cement added, has recently come to be used as a new form of geomaterial. The shear strength and deformation behaviours of GCA are greatly determined by its relative density or void ratio. A series of drained triaxial compression tests were performed on cylindrical specimens of GCA at confining pressures of between 50 kPa and 400 kPa at initial relative densities of 50%, 70% and 80%. Experimental results show that a rise in relative density increases the peak shear strength and intensifies the dilation behaviour. The initial tangent modulus and secant modulus of the stress-strain curve increase with increasing initial relative density, whereas the axial and volumetric strains at failure decrease with level of initial relative density. The stress-dilatancy relationships of GCA at different relative densities and confining pressures display similar tendency. The dilatancy behaviour of GCA is modelled by the Nova rule and the material property N in Nova rule of GCA is much larger than that of natural sand.

Germ Cell Aspiration (GCA) Method as a Non-fatal Technique for Sex Identification in Two Bivalves (Gomphina veneriformis and Tegillaca granosa)

  • Lee, Jung-Sick;Ju, Sun-Mi;Park, Ji-Seon;Jin, Young-Guk;Shin, Yun-Kyung;Park, Jung-Jun
    • Development and Reproduction
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    • v.14 no.1
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    • pp.7-11
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    • 2010
  • This study attempted to verify the possibility of using germ cell aspiration (GCA) method as a non-fatal technique in studying the life-history of equilateral venus, Gomphina veneriformis (Veneridae) and granular ark, Tegillarca granosa (Arcidae). Using twenty-six gauge 1/2" (12.7mm) needle, GCA was carried out in equilateral venus through external ligament. In granular ark, GCA was performed by preventing closure of the shells by inserting a tongue depressor between the shells while still open. The success rate of sex identification using the GCA method was 95.6% for the equilateral venus (n=650/680) and 94.3% for the granular ark (n=707/750). Mortality of equilateral venus, which spent 33 days under wild conditions, was 13.8% (n=90/650) while the mortality of granular ark, which spent 390 days under wild conditions, was 2.4% (n=17/707). Although we believe that GCA does not appear to cause death in equilateral venus or granular ark, the success rate in employing of this methodology may differ depending on the level of proficiency of the researcher and reproductive stage of the bivalve. This study concludes that GCA is a convenient non-fatal methodology, which can be employed to identify sex and investigate gonadal maturity in Gomphina veneriformis and Tegillarca granosa.

Combining Ability Test of F1 Generation by Diallel Cross in Kidney Bean (이면교잡에 의한 강낭콩 F1 세대의 조합능력 검정)

  • Kim Yong-Chul
    • Journal of Life Science
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    • v.15 no.2 s.69
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    • pp.211-214
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    • 2005
  • The studies were conducted to obtain basic informations on inheritance of some quantitative characters in kidney bean (Phaseolus vulgaris L.). Seven parents (Felibon, Renka, Processor, Kaboom, $BO_{22}$, Local variety $\#1$ and Local variety $\#2)$ and $F_1$ hybrids of 21 crosses from a set of diallel cross among varieties were used to estimate combining ability for eight agronomic characters such as days to flowering, days to maturity, stem length, pod numbers per plant, pod length, grain numbers per plant, 100-grain weight and grain weight per plant. General combining ability (GCA) and specific combining ability (SCA) were significantly different among all characters, and values of GCA were greater than those of SCA in all characters except number of grains per plant. In effect of GCA, Felibon expressed high GCA effect for days to flowering and number of grains per plant. Local variety $\#1$ showed high GCA effect for 100-grain weight and stem length. Local variety $\#2$appeared to high GCA effect for 100-grain weight and grain weight per plant. Processor expressed high GCA effect for days to maturity and grain weight per plant. Kaboom showed high GCA effect days to flowering and days to maturity. $BO_{22}$ appeared high GCA effect for all characters except for days to flowering, days to maturity and stem length. In the SCA effect, crosses of Felibonx Renka and Local variety $\#2{\times}Processor$ exhibited in high negative effect for days to flowering. Thus, these crosses were evaluated to useful for breeding early maturing variety. Crosses of breeding high yield variety were considered of $Felibon{\times}Local$ variety $\#1$, $Felibon{\times}Renka$ and Local variety $\#2{\times}BO_{22}$.

Variation in the Properties of Contaminated Coastal Sediment with the Mixing of Alkaline Industrial By-product (알칼리성 산업부산물의 혼합에 따른 연안 오염퇴적물의 성상 변화)

  • Park, Seongsik;Woo, Hee-Eun;Lee, In-Cheol;Kim, Do-Hyung;Park, Jeonghwan;Kim, Jinsoo;Kim, Kyunghoi
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.25 no.7
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    • pp.914-919
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    • 2019
  • A mesocosm experiment considering water exchange was conducted to evaluate the change in the properties of contaminated coastal sediment. The contaminated coastal sediment sample was prepared by mixing with granulated coal ash(GCA), which is an alkaline industrial by-product. During one month of observation time, the phosphate concentration of the GCA sample case was measured to be 19.0 and 0.4 mg/L lower than that of the control sample at the pore water and overlying water, respectively. The hydrogen sulfide concentration of the GCA sample case was 5.0 mg/L, which is significantly lower than that of the control sample(112.5 mg/L). Further addition of GCA in the sediment reduced the concentrations of phosphate and hydrogen sulfide, and could enhance the adsorption reaction, when compared to the sediment without GCA. The dissolved oxygen concentration in the overlying water of the GCA sample was measured to be 3.47 mg/L higher than the control sample. From the above results, we confirmed that GCA is an effective material for reducing pollutants in coastal sediment.

Calcium permeability of transient receptor potential canonical (TRPC) 4 channels measured by TRPC4-GCaMP6s

  • Ko, Juyeon;Myeong, Jongyun;Yang, Dongki;So, Insuk
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.1
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    • pp.133-140
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    • 2017
  • Conflicting evidence has been obtained regarding whether transient receptor potential cation channels (TRPC) are store-operated channels (SOCs) or receptor-operated channels (ROCs). Moreover, the Ca/Na permeability ratio differs depending on whether the current-voltage (I-V) curve has a doubly rectifying shape or inward rectifying shape. To investigate the calcium permeability of TRPC4 channels, we attached GCaMP6s to TRPC4 and simultaneously measured the current and calcium signals. A TRPC4 specific activator, (-)-englerin A, induced both current and calcium fluorescence with the similar time course. Muscarinic receptor stimulator, carbachol, also induced both current and calcium fluorescence with the similar time course. By forming heteromers with TRPC4, TRPC1 significantly reduced the inward current with outward rectifying I-V curve, which also caused the decrease of calcium fluorescence intensity. These results suggest that GCaMP6s attached to TRPC4 can detect slight calcium changes near TRPC4 channels. Consequently, TRPC4-GCaMP6s can be a useful tool for testing the calcium permeability of TRPC4 channels.

Combining Ability and Degree of Heterosis in Sucker Producing Characteristices of Flue-cured Tobacco(Nicotiana tabacum L.) (황색종 연초의 곁순 발생에 대한 조합능력과 Heterosis 정도)

  • 정석훈
    • Journal of the Korean Society of Tobacco Science
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    • v.22 no.1
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    • pp.31-38
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    • 2000
  • Seven flue-cured tobacco(Nicotiana tabacum) varieties and their 21 progenies in Fl and F2 generation, half diallel crosses(no reciprocal), were tested for the degree of heterosis and combining abilities in sucker producing character according to topping and suckering treatment. Significant difference in number and weight of sucker was observed among seven cultivars. The values of general combining ability(GCA) were greater than those of specific combining ability(SCA) in weight and number of sucker in F$_1$ generation. In topping and suckering plot, Cocker 86, McNair 944, and Va 115 revealed the significant negative GCA effects for number and weight of sucker, but By 104 and Speight G-28 did positive GCA. Without topping and suckering, GCA effects for sucker weight in Cocker 139 and Cocker 86 were negative and those for sucker number in Va. 115 were also negative. Negative SCA values in sucker weight could be observed in F$_1$ generation of Cocker 86 X BY 104 and Speiht G-28 X Cocker 86, in F$_2$ of Hicks $\times$ Speight G-28 and McNair 944 $\times$ BY 104 in topping and suckering plot. SCA in F$_1$ of McNair 944 X Cocker 86 and Speight G-28 X Cocker 139 was negative without topping and suckering. The value of heterosis in sucker producing character of F$_1$ hybrids was positive

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