• Journal of The Korean Astronomical Society
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• v.30 no.1
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• pp.83-94
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• 1997

We have identified the candidates for the primordial galaxies in the process of formation in the Hubble Deep Field (hereafter HDF). In order to select these objects we have removed objects brighter than 29-th magnitude in the HDF images and smoothed the maps with the Gaussian filters with the FWHM of 0.8' and 4' to obtain the difference maps. This has enabled us to find. very faint diffuse structures close to the sky level. Peaks are identified in the difference map for each of three HDF chips with three filters (F450W, F606W, and F814W). They have the apparent AB magnitudes typically between 29 and 31. The objects identified in different wavelengths filters have a strong cross-correlations. The correlation lengths are about 0.8'. This means that an object found in one filter can be also found as a peak within 0.8' separation in another filter, thus telling the reality of the identified objects. This angular scale is also the size of the primordial galaxies which have strong color fluctuations on their surfaces. Their large-scale distribution quite resembles that of nearby galaxies, supporting the idea that these objects are ancestors of the present bright galaxies forming at statistically high density regions. Inspections on individual objects show that these primordial galaxy candidates have tiny multiple glares embedded in diffuse backgrounds. Their radial light distributions are quite different from that of nearby bright galaxies. We may be now looking at the epoch of galaxy formation.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.315.3-316
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• 2002

A universal set of genes encodes the components of dissociated. type II. fa11y acid synthase system that is responsible for producing the multitude of fa11y acid structures found in bacterial membranes. We examined the biochemical basis for the production of fatty acids by bacteria. Several genes from HaemophHus influenzae Rd and three genes from Enterococcus faecalis V583 were predicted to encode homologs of the ${\beta}$-ketoacyl-acyl carrier protein synthases I or II or III of Escherichia coli(FabB or BabF, or FabH)were identified in the genomic database. The protein products were expressed. purified, and biochemically characterized. efFabH and hF abH carried out the initial condensation reaction of fatty acid biosynthesis with acetyl-Coenzyme A as a primer. and hFabB and efFabF1 carried out the elongation condensation reaction of fatty acid biosynthesis with myrixtoyl-ACP.

• Bulletin of the Society of Naval Architects of Korea
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• v.12 no.2
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• pp.43-58
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• 1975

There are many reports on fatigue crack of metallic materials but most of them relate crack propagation rate to stress intensity factor. The problem of crack propagation is not yet clarified, especially the bridge between micro and macro phenomena In this experiment rotating bending fatigue tests have been carried out with smoothed specimen of rolled steel plates including 0.2% carbon under application of three stress conditions to investigate the slip band and the crack propagation behaviour. The results obtained are as follows; 1) The length of cracks which have grown at initial crack tips can be expressed as follows; $l=Ae^{BNr}$(A,B: constant, $N_r$: cycle ratio) $\frac{dl}{dN}=\frac{AB}{N_f}{\cdot}e^{BNr}$($N_f$:fatigue life) 2) The ratio of slipped grain number to total grain number is $S_f=7{\sigma}-5.6$-5.6{\sigma}_c$($\sigma$: stress amplitude) (${\sigma}_c$: fatigue limit) 3) When the fatigue process transfers from Stage I to Stage II, the crack which propagates into specimen changes its direction from that of the maximum shear stress to the direction of perpendicular to principal stress and this is same in the circumferential direction of specimen. the crack propagation behaviors of both sides of a crack are different each other when they approach to the grain boundary.

• Journal of Life Science
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• v.27 no.3
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• pp.295-300
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• 2017

This study examined the association between genotypes of the isocitrate dehydrogenase 3, beta subunit (IDH3B) gene and economic traits in an $F_2$ population of Duroc and Jeju (South Korea) native black pigs (JBPs). The genotypes was determined the presence/absence of a 304-bp insertion/deletion fragment in the promoter region of the IDH3B gene for JBP, Duroc, and their $F_1$ and $F_2$ progeny. Three genotypes (AA, AB and BB) were found in the $F_1$ and $F_2$ populations, but there was no AA genotype found in JBP and no BB in Duroc. Association analysis results showed the significant differences with carcass weights (CW), backfat thicknesses (BFT) and eye muscle area (EMA) (p<0.05), but not with growth traits including body weights and average daily gains at different stages, reproductive traits including teat numbers, and crude fat contents (CFAT) measured in longissimus dorsi (p>0.05). The $F_2$ pigs possessing the IDH3B BB homozygote had heavier CW ($72.92{\pm}11.133kg$), thicker BFT ($25.75{\pm}6.06mm$), and larger EMA ($23.82{\pm}4.825cm^2$) than those from the other genotypes (p<0.05). These results were estimated that there are biological roles related with IDH3B genotypes resulting development of EMA, BFT, and CW but not with intramuscular fat deposition during late period of pig production. Our findings suggest that the 304-bp insertion allele of porcine IDH3B may be a genetic marker for marker assistant selection for improving meat productivity of the Jeju Black pig and Duroc-related molecular breeding systems.

• Journal of the Korean Chemical Society
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• v.54 no.3
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• pp.275-282
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• 2010

2-Fluorocyclopropanemethanol and 2-chlorocyclopropanemethanol have been studied with MP2 and B3LYP methods with 6-311++G(d,p) basis set. The optimized structures show several stable conformers. The most stable conformer show the possibility of intramolecular hydrogen bonding, but the distance between $H{\cdots}F$, or $H{\cdots}Cl$ is longer than van der Waals radii and it may not be strong covalent bonding. Rather the second stable conformer has optimum structure for intramolecular hydrogen bonding but the energy of the conformer is 5 ~ 7 kJ higher than the most stable conformer. When the methanol group and the F or Cl atom have opposite direction, the conformers are less stable than the most stable conformer.

• Animal Bioscience
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• v.34 no.10
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• pp.1695-1704
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• 2021

Objective: The aim of this work was to assess the effect of ergothioneine (ESH)-enriched mushroom extract on oxidative stability, volatile compounds, and sensory quality of emulsified sausage. Methods: The ESH content was determined by high performance liquid chromatography. The antioxidant activity of Flammulina velutipes (F. velutipes) extract was determined through radical-scavenging activity of 1,1 diphenyl-2-picryl-hydrazyl, 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) and hydroxyl radicals. Four different groups of emulsified sausage were manufactured: control, no antioxidants; BHA, 0.01% butylated hydroxyanisole; EEME, 0.8% ESH-enriched mushroom (F. velutipes) extract; AE, 0.012% authentic ESH, after storage for 14 days (at 4℃), the quality of sausage including oxidative stability (2-thiobarbituric acid reactive substances and protein carbonyls content), volatile compounds and sensory quality were studied. Results: It was demonstrated that adding ESH-enriched F. velutipes extract to sausage could effectively prevent lipid and protein oxidation, and its efficacy was equivalent with 0.01% BHA. During meat processing, the ESH mainly contributed to the antioxidative activity of F. velutipes extract. The flavor and sensory attributes of emulsified sausage were improved through adding ESH-enriched F. velutipes extract. Conclusion: Accordingly, the extract of F. velutipes contained high-level of ESH and could be a good antioxidant candidate for processed meat production.

• The Journal of the Petrological Society of Korea
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• v.4 no.1
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• pp.61-87
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• 1995

On the basis of lithology, the Precambrian Hongjesa Granitic Gneiss can be locally zoned into granoblastic granitic gneiss, porphyroblastic granitic gneiss, migmatitic gneiss from its center to the marginal part. There are no distinct differences in mineral assemblages by lithologic zoning, but it partly shows the change of mineral assemblage in the adjacent with migmatitic gneiss, thus mineral assemblage can be subdivided into Zone I and Zone II. In terms of mineral compositions, the characteristics of Zone I are coexisting K-feldspar+muscovite+sillimanite. The characteristics of Zone II are (1) breakdown of muscovite, (2) coexisting garnetScordierite, (3) coexisting garnet+cordierite + orthoamphibole. The Buncheon Granitic Gneiss is mainly composed of augen gneiss. In the adjacent area with Honjesa Granitic Gneisses, Buncheon Granitic Gneiss has the mineral assemblage of sillimanite+biotite+K-feldspar+(kyanite). Kyanite occurs as relict grains in the Buncheon and Hongjesa Granitic Gneissess. Kyanite shows anhedral to subhedral form and coexists with sillimanite in only one of these samples. Garnet from a migmatitic gneiss (Zone 11) has relatively high $X_{Fe}$ value in core and rim. Garnet from a porphyroblastic granitic gneiss(Zone I) has relatively homogemeous core but compositionally-zoned rim. Biotites show various colour from greenish-brown, brown to reddish brown at maximum adsorption. Also, the Ti, and Mg content in biotites increases from Zone I to Zone II. The plagioclases shows the chemical composition of $Ab_{84}An_{16}$ -$Ab_{70}An_{30}$ (oligoclase) in Zone I and $Ab_{70}An_{30}$ -$Ab_{50}An_{50}$(andesine) in Zone 11. These variations indicate that the gneisses in the study area experienced a upperamphibolite facies. The presence of kyanite as relict grains indicates that the metamorphic rocks in this area exprienced a high-temperature/medium-pressure type metamorphism, followed by high-temperaturellow-pressure metamorphism. Metamorphic P-T conditions for each gneiss estimated from various geothermobarometers and phase equilibria are 698-$729^{\circ}C$/6.3-11.3 kbar in augen gneiss, 621-$667^{\circ}C$/1.0-5.4 kbar in migmatitic gneiss, and 602-$624^{\circ}C$/1.9-3.4 kbar in porphyroblastic granitic gneiss. These data suggest that the study area was subjected to a clockwise P-T path with isothermal decompression (dP/dT=about 60 bar/$^{\circ}C$).

• Journal of Animal Science and Technology
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• v.46 no.6
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• pp.887-896
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• 2004

The present study was carried out to investigate the blood markers of Mongolian horses. The blood redcell types and blood protein types(biochemical polymorphisrns) were tested from 19 Mongolian horses by serological and electrophoretic procedure, and their phenotypes and gene frequencies were estimated. The blood group and biochemical polymorphism phenotypes observed with high frequency were $A^{af}$(42.1%), $C^a$(89.5%), $K^-$(84.2%), $U^a$(63.2%), $P^a$(42.1%) $P^-$42.1%), $Q^c$(31.6%) $Q^-$(31.6%), $AL^{AB}$((52.6%), AI$B^K$(89.5%), $ES^1$(63.2%), $GC^F$(78.9%), $HB^BI$1(68.4%), PG$D^F$(84.2%), $TF^{FIR}$(21.1%), $TF^{F2R}$(21.1%)(21.1%), and genotypes $D^{cgm/dghm}$(15.8%), $D^{dghm/dghm}$(15.8%), $D^{ad/dghm}$(10.5%), $D^{ade/dghm}$(10.5%), in Mongolian horses, respectively. Alleles observed with high frequency were $A^a$(0.4211), $C^a$(0.8947), $K^-$(0.8421), $U^a$(0.6316), $P^a$(0.4474), $Q^c$(0.4474), $D^{dghm}$(0.4211), $AL^B$(0.6579), $AIB^K$(0.9211), $ES^I$(0.7895), $GC^F$(0.8947), $HB^{BI}$(0.7895), $PGD^F$(0.8421) and $TF^R$(0.3421) in Mongolian horses. These results present basic information for estimating the genetic relationships between the Korean native horse, and developing a system for parentage verification and individuals identification in Mongolian horse.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.405-411
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• 2011

The ab initio calculations for fluoromethyl fluoroperoxides have been carried out using MP2/6-311G(d,p) and B3LYP/6-311++G(d,p) method. The structural optimizations were performed for several isomers and conformers of methyl fluoroperoxide, $CH_3OOF$ and the vibrational frequencies were calculated. The most stable conformer of $CH_3OOF$ is skew form and has fairly short O-O bond distance. The trans and cis conformers have 8-12 kcal/mol higher energies than skew form and the other isomers are very unstable. The structures of $CH_2FOOF$, $CHF_2OOF$ and $CF_3OOF$ are also optimized and vibrational frequencies were calculated. These molecules also have skew forms as the lowest energy conformers. The O-O bond distances are longer and C-O bond distances are shorter than $CH_3OOF$, but the structural parameters are almost independent of the number of fluorine atoms in methyl group.

• Journal of the Korean Society of Costume
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• v.35
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• pp.181-193
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• 1997

The objectives of this study were to classify bedclothes purchase motives and to examine how bedclothes purchase mo-tives and design preferences very accord-ing to age and income. Samples were 217 housewives residing in metropolitan area. Questionnaire included 17 Likert type items of bedclothes pur-chase motive measure 12 items of color preference 7 items of pattern (floral geo-metric abstract stripe plaid polka dot, and paisley pattern). The results of the study were as fol-lows. 1. 5 factors of bedclothes purchase mo-tives were derived by factor analysis ; F .1 'design': F 2. "brand' ; F.3. 'deficiency'; F. 4. 'fabric' F.5. 'economical reason' 2. Subjects perceived design and utility area to be important motives for bed-clothes purchase. 3. Cholor preference of bedclothes was in the order of white pale blue pale green and pale orange. Pattern preference was in the order of stripe plaid solid color floral and polka dot pattern. The combi-nation of patterned fabric and solid color fabric was liked better than the combina-tion of analogic color and the combination of contrasting color. 4. The women in their 20's liked navy blue red stripe plaid pattern and solied color better than 30's and 40's . 40's liked abstract and paisley pattern better then 20's and 30's 5. Low income group lied navy blue and solid color fabric more than the mid-dle and high income group and liked ab-stract pattern less than the middle and high income group. 6. Women in their 20's perceived design to be important motive more than 30's and 40's. 30's perceived brand to be im-portant motive than 20's and 40's 7. High income group perceived design to be important motive more than the middle and low income group. Low in-come group perceived brand and fabric to be less important motives than the middle and high income group, The present findings provide that age and income had a significant effect on bedclothes purchase motives and design preferences of houesewives. The results that white color and the combination of patterned fabric and solid color fabric were liked best indicated that women prefered clean image and chacteristics de-sign of bdeclothes.