• Korean Journal of Plant Resources
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• v.33 no.6
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• pp.645-650
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• 2020

The mechanism of anti-aging of fermented jujube (Zizyphus jujuba fruits (ZJF)) was investigated using transgenic daf-16 and mev-1 strains of C. elegans. Jujube extracts fermented for 7 days (F7-ZJF) and 14 days (F14-ZJF) with Laetiporus sulphureus were treated to a NGM agar plate with 10-15 transgenic daf-16 and mev-1 strains of the synchronized age. There was no difference of lifespan between the drug-treated group (7-day fermented ex. (F7-zjf-200 ㎍/mL), 14-day fermented ex. (F14-zjf-200 ㎍/mL)) and the non-treatment group in both daf-16 and mev-1 strains. In the thermal stress experiment, F7-zjf-200 ㎍/mL showed a significant (t = 4.017) activity in thermal stress resistance with a 12% higher survival rate than the control group. In the survival test in H2O2, F7-zjf-200 ㎍/mL and F14-zjf-100 ㎍/mL have significant activity in oxidative stress resistance compared to the control group. This study indicates that life span expand of N2 strain of the jujube extract is related to the regulation of daf-16 and inhibition of mev-1 signal in C. elegans.

• 한국초전도학회:학술대회논문집
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• v.16
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• pp.14-14
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• 2006

• Korean journal of applied entomology
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• v.14 no.4 s.25
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• pp.199-204
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• 1975

One thousand forty-four isolates of Pyricularia oryzae obtained during the period 1962-1974 front blast-infected rice samples from all rice-growing areas of Korea were tested on the Japanese differential set of twelve rice varieties. Twenty-seven races of the fungus were differentiated. The number of races falling in groups T,C and N were 4, 15 and 8, respetively. Since only Japonica type varieties had been cultivated widely before 1966, N-race groups were found to be most Prevalent with a frequency of about $85\%$ of the total isolates. After 1966, T-and C-race groups gradually increased to $21\%$ and $42\%$ respectively, as a result of the widespread cultivation of Tongil bred from a cross between IR8 x(Yukara x T(N)1. Before 1966, a few T, and C-race groups occurred only in the Suweon region; since 1966, most of the races differentiated have been uniformly distributed throughout the country regardless of region. The most prevalent races in Korea were N-2 and C-8. The variety Tetep was resistant to all races previously identified in Korea, but a new race (T-d) to which Tetep is susceptible has been found each year since 1973. It appears likely that races capable of attacking Indica types of rice will become increasingly prevalent and a programme of continuous screening is needed to detect new races as soon as they appear.

• Analytical Science and Technology
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• v.25 no.5
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• pp.300-306
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• 2012

This study reports the stable carbon and nitrogen isotope of mummy, the preserved human time capsule from Joseon Dynasty. The stable isotopic composition of biological tissue is expected to be a direct and constant function of diet because the stable isotope ratios do not decay or change in abundance through time. Over the past three decades, stable carbon and nitrogen isotope analysis has been extensively applied for archaeological topics. However, this is the first case in Korean mummy to extract palaeodietary information using stable isotope analysis. We extracted isotopic information from bone collagen and hair keratin, which reflects the lifetime average diet and short-term diet, respectively. The average values of ${\delta}^{13}C$ and ${\delta}^{15}N$ values are -19.0‰ and 11.4‰ (bone collagen), and -21.3‰ and 14.3‰ (hair keratin). Stable carbon isotope shows a mainly $C_3$-based diet from cradle to grave. On the other hand, there is significant difference in stable nitrogen isotope which implies a relatively enriched diet before death. We expect this study opens up a potential to understand the palaeodietary lifestyle in Joseon Dynasty.

• Korean Journal of Environmental Agriculture
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• v.9 no.2
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• pp.153-159
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• 1990

Two fractions(microsomal and soluble) were prepared by ultracentrifugation(105,000G for 1hr at $4^{\circ}C$) from pig liver in order to find the major factor in Diazinon degradation. The two enzyme activities showed the same value, but Diazinon was degraded three times in microsomal fraction more than in soluble fraction. And with addition of EPN, Beam and PBO, degradation of diazinon was inhibited(29, 30 and 60%) as well as Monooxygenase activity (14, 15 and 35%) in microsomal fraction, respectively.

• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.20-24
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• 2013

Food irradiation has recently become one of the most successful techniques to preserve food with increased shelf life. This study aims to analyze hydrocarbons in almonds (Prunus amygosalus L.) and peanuts (Arachis hypogaea) induced by electron beam irradiation. The samples were irradiated at 0, 1, 3, 5 and 10 kGy by e-beam and using florisil column chromatography fat, and content was extracted. The induced hydrocarbons were identified using gas chromatography-mass spectrometry (GC/MS). The major hydrocarbons in both irradiated samples were 1,7-hexadecadiene ($C_{16:2}$) and 8-heptadecene ($C_{17:1}$) from oleic acid, 1,7,10-hexadecatriene ($C_{16:3}$) and 6,9-heptadecadiene ($C_{17:2}$) from linoleic acid and 1-tetradecene ($C_{14:1}$) and pentadecane ($C_{15:0}$) from palmitic acid. Concentrations of the hydrocarbons produced by e-beam were found to be depended upon the composition of fatty acid in both almonds and peanuts. The $C_{n-2}$ compound was found to be higher than $C_{n-1}$ compound in oleic acid and palmitic acid, while in case of linoleic acid, $C_{n-1}$compound was higher than $C_{n-2}$ compound. The radiation induced hydrocarbons were detected only in irradiated samples, with 1 kGy or above, and not in the non-irradiated ones. The production of 1,7-hexadecadiene ($C_{16:2}$), 8-heptadecene ($C_{17:1}$), 1,7,10-hexadecatriene ($C_{16:3}$) and 6,9-heptadecadiene ($C_{17:2}$), in high concentration gave enough information to suggest that these may be the possible marker compounds of electron beam irradiation in almonds and peanuts.

• Korean Journal of Ichthyology
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• v.29 no.2
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• pp.101-108
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• 2017

Egg development and early life history of the Korean natural monument fish Hemibarbus mylodon (Pisces: Cyprinidae) were investigated to provide basic data on biological characteristics and ecological recovery. Adult fish were collected from nature and transferred to the laboratory. For the first time, artificial maturation of females and males succeeded after 15 months of indoor culture. Mature eggs and sperm were obtained using Ovaprim injections (0.5 mL/kg) and then the eggs were fertilized using the dry method in the laboratory. The mature eggs were adhesive, turbid, and greyish; they averaged $2.21{\pm}0.06mm$ (n=30) in diameter. The embryos began to hatch about 78 h after fertilization at a water temperature $20{\pm}1^{\circ}C$, and the newly-hatched larvae were $6.6{\pm}0.75mm$ in total length (TL). At 14 days after hatching, the post-larval individuals were $13.5{\pm}0.23mm$ (TL), and their yolk sacs were completely absorbed. Twenty one days after hatching, they entered the juvenile stage and reached $13.5{\pm}0.23mm$ (TL). At 100 days after hatching, their band patterns, external form, and a pair of barbels were similar to those of adults, and they averaged $33.0{\pm}4.25mm$ (TL). The breeding technology and characteristics of early life history obtained in this study will be very helpful for conservation of H. mylodon in nature.

• Korean Journal of Ecology and Environment
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• v.33 no.2 s.90
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• pp.176-186
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• 2000

The present study was carried out to clarify the structure and dynamics of copepod community and the relationship between this community and environmental factors during the period from February 1998 to July 1999. Copepods consists of 21 genera and 32 species, monthly variations of number of species were 15 species in May, 1998 and 2 species November, 1998. The number of species were 22 species in station 12 and station 1, 2, 3 occurred nauplii of copepoda only. Average abundance ranged from $8,330\;ind./m^3$ (in June, 1999) to $177\;ind./m^3$ (in November, 1998). Relationships between water temperature and number of species were as follows: 20 species occurred from 20.1 to $25.0^{\circ}C$ and nuplii of copepoda only occurred from 0.0 to $5.0^{\circ}C$. The number of species by salinity range were 19 species in $20.1{\sim}25.0%_o$ and 9 species in $0{\sim}0.5%_o$. The number of species by trophic state index (TSIm) of chlorophyll a were 25 species in oligotrophic state and 9 species in eutrophic state. Relationships between pH and number of species were as follows: 20 species occurred from 7.6 to 8.0 and from 9.1 to 9.5 was none. The number of species by DO range were 22 species in 6.5 to 7.5 mg/l and 1 species in 14.5 to 15.5 mg/l. The percentage calculated effect by stepwise multiple regression of the pearson correlation coefficient value of environmental factors and copepoda abundance (station 1-station 4) revealed that positive effect was 15.49% in COD, 25.86% in $Cl^-$, 19.75% in $NO_2-N$ and negative effect was 28.30% in $NO_3-N$. Also, Positive effect (station 5-station 12) revealed that 29.49% in water temperature, 28.27% in $NO_3-N$, 22.87% in $NO_2-N$ and negative effect was 30.18% in conductivity and 13.53% in DO.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2006.10a
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• pp.14-17
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• 2006

This paper describes a novel processing technique for fabrication of polymer-derived SiCN (silicone carbonitride) microstructures for super-temperature MEMS applications. PDMS (polydimethylsiloxane) mold is fabricated on SU-8 photoresist using standard UV photolithographic process. Liquid precursor is injected into the PDMS mold. Finally, solid polymer structure is cross-linked using HIP (hot isostatic pressure) at $400^{\circ}C$, 205 bar Optimum pyrolysis and anneal ins conditions are determined to form a ceramic microstructure capable of withstanding over $1400^{\circ}C$. The fabricated SiCN ceramic microstructure has excel lent characteristics, such as shear strength (15.2 N), insulation resistance ($2.163{\times}10^{14}\;{\Omega}$) and BDV (min. 1.2 kV) under optimum process condition.

• Korean Journal of Crystallography
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• v.11 no.1
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• pp.42-45
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• 2000

The complex [Zn(L)Cl](H₂O)(ClO₄) (1) (L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,O/sup 1.18/,O/sup 7.12/]docosane) has been prepared and characterized by X-ray crystallography. 1 crystallizes in the monoclinic space group P2₁/c, with a=8.883(1), b=19.319(9), c=15.124(2)Å, β=101.65(1)°, V=2542.0(13) ų, Z=4, R₁(wR₂) for 4457 observed reflections of [I>2σ(I)] was 0.0640(0.1557). The coordination geometry around the zinc is a distorted square-pyramid with four nitrogen atoms of the macrocycle occupying the basal sites(Zn-N/sub av/=2.131(2)Å) and a chloride atom at the axial position with the Zn-Cl distance of 2.315(2)Å.