• KSBB Journal
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• v.9 no.3
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• pp.299-305
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• 1994

Taxol contents in various parts of 15 years old yew tree were determined. The descending order of taxol content per unit mass was stem bark, root bark, needle and seed. In the seed, that order was seed coat, embryo and endosperm. The total amount of taxol extractable from a 15 years old yew tree was 1.68 gram. This amount was distributed in needle, stem bark, root bark and seeds as 48.0, 23.8, 27.9 and 0.4%, respectively. Altitudinal variation of taxol content was also observed. More taxol was observed in yew trees grown at high altitude over 1000m above sea level. Calli and suspension cultures were induced from various yew trees. The presence of taxo] in cultured cells was established bv HPLC. The taxol content in cultured cells were different according to the source of explants. These results may be useful for the goal of large scale taxol production by cultured yew tree cells.

• Journal of Astronomy and Space Sciences
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• v.26 no.1
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• pp.9-24
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• 2009

We compare the relation among the annual distribution of sunspots: coronal mass ejections (CMEs) and geomagnetic storms and North-South asymmetry during solar cycle 23. For this purpose, we calculate correlation coefficients between (i) annual distribution and N-S asymmetry of CMEs - sunspots (ii) distribution of CMEs - occurrence number of geomagnetic storms (iii) distribution of sunspots - occurrence number of geomagnetic storms. We find that (i) the annual distribution of total CMEs has good correlation with distribution of annual average of sunspots but poor correlation with N-S asymmetry of sunspots, N-S asymmetry of CMEs has good correlation with N-S asymmetry of sunspots: (ii) total and N-S asymmetry of CMEs have poor correlation with occurrence number of geomagnetic storms, it's, however, well correlated with the classified groups of CMEs (Ap, Dst and an indices vs. fast CMEs($\upsilon$ > $1000kms^{-1}$), Dst index vs. Halo CMEs), and (iii) sunspot numbers and area are correlated with occurrence number of geomagnetic storms. We conclude that annual distribution of CMEs and sunspots have well correlated with geomagnetic storms, N-S asymmetry of CMEs and sunspots have poor correlated with the geomagnetic storms.

• Explosives and Blasting
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• v.27 no.1
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• pp.7-20
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• 2009

In this study, 5 steps of different delay intervals are applied to a plasma rock-breaking machine that is driven by electric shocks in order to improve the workability of the traditional single-shot type plasma rock-breaking operation. The sequential steps use the electrolyte volume per delay of 1, 2, 3, 4, 5 kg and it has been analyzed to measure the delay time and level of the ground vibration and noise according to exploding. The delay time of the rock-breaking machine by an electric shock of 5 steps has used about 40~50ms at the electrolyte connected from 1 to 3 holes, about 70~80ms at the electrolyte connected from 4 to 5 holes. It is identified that the extents of the ground vibration is low to 1 over 3~6 compared with that of the emulsion explosives.

• Journal of the Korean Ceramic Society
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• v.37 no.11
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• pp.1084-1090
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• 2000

(Bi$_2$O$_2$)$^{2+}$층 사이에 두 개의 Ta-O 팔면체로 연결된 Bi 계의 층상 페로브스카이트 구조인 SrBi$_2$Ta$_2$O$_{9}$ (SBT) 박막을 XPS를 이용하여 깊이별 화학 상태 변화를 분석하였다. 아르곤 이온으로 SBT 박막을 식각하면, SBT 박막의 각 구성물들은 가속 Ar$^{+}$ 이온의 에너지에 따라 변화한다. SBT 각 구성물 중 Sr 3d의 화학 상태는 Ar$^{+}$ 이온의 에너지변화에 따라 근소하게 변화한다. 반면에, Ta 4f와 Bi 4f의 화학 상태 변화는 인가되는 Ar$^{+}$ 이온 에너지에 확실하게 의존한다. 특히, Bi 4f는 Sr과 Ta에 비해 낮은 Ar$^{+}$ 이온 에너지에서도 Bi-O의 화학 상태가 금속 Bi 화학 상태로 현저하게 변화한다. 이러한 SBT 박막의 화학 상태 변화는 산호 원자의 선택적인 식각 때문에 발생하며 선택적인 식각은 SBT 박막 내에서 각 구성물과 산소간의 질량 차이와 각 구성물의 열적 안정성에 의존함을 알 수 있다.

• Analytical Science and Technology
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• v.17 no.2
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• pp.117-129
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• 2004

Amitrole in environment, difficult to be analyzed by GC or GC/MS due to high polarity and low volatility, was analyzed by LC/ESI/MS in the study. Maximum peak intensity of amitrole in LC/MS/ESI mass spectrum is m/z 85 of protonated molecular ion $(M+H)^+$ with 30V of cone voltage at SIR mode. It was confirmed that ratios between main ion of amitrole, 85 of protonated molecular ion, and m/z 58 fragmented ion of amitrole, had increased corresponding with the increment of cone voltage from 20V to 70V. The isotope molecular weight of amitrole was $86([M+H])^+$ at LC/MS analysis and the mass spectrum ratio between 85 mass and 86 mass was not different by the change of concentration but similar to theoretical ratio(less than 10% standard deviation).The linearity of standard calibration curve under same condition with sample treatment method had $y=1.09354e^6X+26947.2$ and $r^2=0.99$. Recovery rates in water and soil samples were 77.64~83.44% and 71.11~79.44%, respectively. Reliability of the analysis was performed with 5 repeated measurements at each level of standard concentration and the result showed that relative standard deviation was less than 10%; therefore, the extraction and analysis method in the study suggested that it would be reliable to measure amitrole in water and soil media.

• Journal of Nutrition and Health
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• v.44 no.5
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• pp.355-365
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• 2011

This study investigated how dietary fat affects muscle atrophy and lipid metabolism in various muscles during hindlimb immobilization in rats. Twenty-four male Sprague?Dawley rats had their left hindlimb immobilized and were divided into four groups by dietary fat content and composition. The contralateral hindlimb (control) was compared with the immobilized limb in all dietary groups. Rats (n = 6/group) were fed a 4% corn oil diet (CO), 2.6% corn oil + 1.4% fish oil diet (FO), 30% corn oil diet (HCO), or a 30% beef tallow diet (HBT)after their hind limbs were immobilized for 10 days. Data were collected for the gastrocnemius, plantaris and soleus muscles. Muscle atrophy was induced significantly after 10 days of hindlimb immobilization, resulting in significantly decreased muscle mass and total muscle protein content. The protein levels of peroxisome proliferator activated receptor ${\delta}$ (PPAR${\delta}$) in the plantaris, gastrocnemius, and soleus increased following hindlimb immobilization irrespective of dietary fat intake. Interestingly, the PPAR${\delta}$ mRNA level in the plantaris decreased significantly in all groups and that in the FO group was lower than that in the other groups. The soleus PPAR${\delta}$ mRNA level decreased significantly following hindlimb immobilization in the FO group only. Muscle carnitine palmitoyl transferase 1 (mCPT1) mRNA level was not affected by hindlimb immobilization. However, the mCPT1 mRNA level in the FO group was significantly lower in the plantaris but higher in the soleus than that in the other groups. The pyruvate dehydrogenase kinase 4 (PDK4) mRNA level in the plantaris decreased significantly, whereas that in the soleus increased significantly following hindlimb immobilization. The plantaris, but not soleus, PDK4 mRNA level was significantly higher in the FO group than that in the CO group. The increased PPAR${\delta}$ protein level following hindlimb immobilization may have suppressed triglyceride accumulation in muscles and different types of dietary fat may have differentially affected muscle atrophy according to muscle type. Our results suggest that ${\omega}$-3 polyunsaturated fatty acids may suppress muscle atrophy and lipid accumulation by positively affecting the expression level and activity of PPAR${\delta}$ and PPAR${\delta}$-related enzymes, which are supposed to play an important role in muscle lipid metabolism.

• Korean Journal of Ecology and Environment
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• v.36 no.2 s.103
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• pp.124-138
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• 2003

This paper aimed to analyze the relationship between alga3 bloom patterns and hydrological, limnological data which were collected from major reservoirs in Korea for 8 years (1990${\sim}$1997). Water temperature of river-type reservoirs showed wider seasonal fluctuations than that of lake-type. pH of lake-type reservoirs was low in winter season but high in summer season. In contrast, river-type reservoirs showed high pH in spring and autumn seasons as well, and very low in summer season. COD of lake-type reservoirs and Paldang reservoir was lower (2${\sim}$3 mg/L) than that of Geumgang and Nagdonggang reservoirs (6${\sim}$9 mg/L). Dissolved oxygen (DO) of river-type reservoirs was higher than that of lake-type reservoirs. Seasonal fluctuation pattern of DO saturation in river-type reservoirs was high (80 ${\sim}$100%) and remained relatively constant whereas lake-type reservoirs showed the highest level (93%) in late spring or early summer, which gradually decreased entering winter season(46${\sim}$06%). And monthly variation of DO saturation showed inverse proportion to water volume in lake-type reservoirs. Nutrients concentration in river-type lake is higher than lake-type. Seasonal fluctuation of nutrients (T-N, T-P) in lake-type reservoirs was relatively small than that of river-type reservoirs. Annual mean N/P mass ratio of lake-type reservoirs was higher than that of river-type. Transparency tended to related with the suspended solid concentration in river-type reservoirs. Algal bloom of lake-type and river-type reservoirs occurred at any time except rainfall and winter periods. And it dominated in summer and early autumn, respectively. Algal bloom of river-type reservoirs was higher than that of lake-type. Relationship between rainfall and chlorophyll- a in lake-type reservoirs was relatively high, however river-type reservoirs showed insignificant.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.1
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• pp.41-53
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• 1997

Geochemical data of soil and water samples were presented in order to assess the environmental impart for drinking water sites. Microscopic observation of rock samples and physical and chemical analysis of soil and water samples were undertaken. The geology of study areas are classified into three groups such as granitic rocks, meta-sedimentary rocks and sedimentary rocks. Enrichment of heavy metals derived from those rocks is not found in this study areas. Soils were analyzed for Cu, Pb, Zn, Cd and Cr using AAS extracted by HNO$_3$+HClO$_4$ and 0.1 N HCl. Heavy metal concentrations in soils are within the range of those in uncontaminated soils. In comparison of metal contents extracted by 0.1 N HCl and HNO$_3$+HC1O$_4$, less than 10% of the heavy metals are present in the exchangeable fraction. In particular, an pollution index has been proposed to assess the degree of soil contamination. Pollution index in soils are between 0.03 and 0.47 therefore, soils are not polluted with heavy metals. Deep groundwaters within granitic rocks have been evolved into Na$\^$＋/-HCO$_3$$\^$-/ type, whereas other deep groundwaters evolved into Ca$\^$2＋/-HCO$_3$$\^$-/ type. The predominance of Na$\^$＋/ over Ca$\^$2＋/ in deep groundwaters within granitic rocks is a result of dissolution of plagioclase, but for sedimentary and meta-sedimentary rocks, dissolution of calcite is a dominant factor for their hydrogeochemistry. The pH, conductivity and contents of the most dissolved ions in the water increase with depth. Shallow groundwaters, however, are highly susceptible to pollution owing to agricultural activities, considering the fact that high contents of nitrate, chloride and potassium, and high K/Na ratio are observed in some shallow groundwaters. In a thermodynamic approach, most natural water samples are plotted within the stability fields of kaolinite and smectite. Therefore, microcline and other feldspars will alter to form clay minerals, such as kaolinite and smectite. From the modelling for water-rock interactions based on mass balance equation, models accord well with behavior of the ions and results of thermodynamic studies are derived.

• The Korean Journal of Mycology
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• v.35 no.2
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• pp.96-100
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• 2007

In order to select ${\gamma}-Linolenic$ acid (GLA)-producing fungi, a total of forty-four strains of 4 genera such as Phytophthora, Pythium, Mucor and Rhizopus were obtained from Koran Agricultural Culture Collection (KACC) and then analysed by using GC-FID and GC-MS. GLA was detected on 39 fungal strains, and the highest rate of GLA was found as 24.8% of total fatty acids on Mucor hiemalis f. sp. hiemalis KACC 40264. Total GLA content of Zygomycota was comparatively high - Mucor (14.2%) and Rhizopus (14.3%), whereas that of Oomycetes was low - Phytophthora (3.3%) and Pythium (3.0%). Moreover, total fatty acids of the Zygomycota fungi such as Mucor (15.4 mg/100 ml) and Rhizopus (7.1 mg/100 ml) were higher compared with the Oomycetes such as Phytophthora (2.6 mg/100 ml) and Pythium (4.5 mg/100 ml). Thus, two genera such as Mucor and Rhizopus have higher potential as an useful microbial resource. The total fatty acid content varies even within the strains of the same genus e.g. Mucor. M. blumbeus KACC 40935 showed the highest values on productivity (18.2%) of GLA and total fatty acid contents (50.8 mg/100 ml liquid medium).

• Korean Journal of Remote Sensing
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• v.14 no.4
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• pp.353-365
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• 1998

Light absorption coefficient per unit mass of particles, i.e., specific absorption coefficient, is important as one of the main parameters in developing algorithms for ocean color remote sensing. Specific absorption coefficient of chlorophyll ($a^*_{ph}$) and suspended sediment ($a^*_{ss}$) were analyzed with a spectrophotometer using the "wet filter technique" and "Kishino method" for the seawater collected in the Yellow and Mediterranean Sea. An improved data-recovery method for the filter technique was also developed using spectrum slopes. This method recovered the baselines of spectrum that were often altered in the original methods. High $a^*_{ph}({lambda})$ values in the oligotrophic Mediterranean Sea and low values in the Yellow Sea were observed, ranging 0.01 to 0.12 $m^2$/mg at the chlorophyll maximum absorption wavelength of 440 nm. The empirical relationship between $a^*_{ph}$(440nm) and chlorophyll concentrations () was found to fit a power function ($a^*_{ph}$=0.039 $^{-0.369}$), which was similar to Bricaud et al. (1995). Absorption specific coefficients for suspended sediment ($a^*_{ss}$) did not show any relationship with concentrations of suspended sediment. However, an average value of $a^*_{ss}$ ranging 0.005 - 0.08 $m^2$/g at 440nm, was comparable to the specific absorption coefficient of soil (loess) measured by Ahn (1990). The morepronounced variability of $a^*_{ss}$ than $a^*_{ph}$ was determined from the variable mixing ratio values between particulate organic matter and mineral. It can also be explained by a wide size-distribution range for SS which were determined by their specific gravity, bottom state, depth and agitation of water mass by wind in the sea surface.