• Korean Journal of Ichthyology
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• v.19 no.4
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• pp.274-285
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• 2007

The subfamily Chrominae of damselfishes (Teleostei: Pomacentridae) includes the genus Chromis and Dascyllus. They are found throughout the tropical oceans and form a major component of coral reef communities. There are 5 species of the Chrominae currently recognized in Korea. This study was conducted to infer phylogenetic position of two Korean Chromis species and one Dascyllus species within general category of their each genus in worldwide level. This study also includes one species of Japanese Dascyllus. In the phylogenetic analysis, the Japanese D. aruanus grouped with D. aruanus previously reported from French Polynesia. Korean Chromis fumea grouped with Australian C. nitida and the p-distance value between the two species is relatively very low (0.047). Korean C. notatus grouped together with C. flavomaculata (New Caledonia). In the sequence analysis of some Korean and Japanese damselfishes, there was no sequence variation between D. melanurus (Jeju, Korea) and D. melanurus (Indo-Pacific), but the sequences of the two populations were different in only one nucleotide sites from that of D. melanurus in Indonesian Archipelago. The sequences of Dascyllus aruanus (Japan) were different in two nucleotide sites from it in French Polynesia. There were high difference between the sequences of two Korean species, Chromis fumea and Korean C. notatus. The variations among mitochondrial cytochrome b sequences indicate that the gene sequence could be used as DNA barcode for identification of local populations of D. aruaus and D. melanurus as well as species level.

• Journal of the Korean Magnetic Resonance Society
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• v.3 no.1
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• pp.12-26
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• 1999

The 1H NMR signals of the heme methyl, propionate and related chemical groups of cytochrome C3 from Desulfovibrio vulgaris Miyazaki F (D.v. MF) were assigned by means of 1D NOE, 2D DQFCOSY and 2D TOCSY spectra. They were consistent with the assignments of the hemes with the highest and second-lowest redox potentials reported by Gayda et al. [Reference: 15]. The heme assignments were also supported by NOE between the methyl groups of these hemes and the side chain of Val-18, All the results contradicted the heme assignments for D.v. MF cytochrome C3 made on the basis of NMR [Reference: 11]. Based on these assignments, the interaction of cytochrome C3 with ferredoxin I was investigated by NMR. The major interaction site of cytochrome C3 was identified as the heme with the highest redox potential, which is surrounded by the highest density of positive charges. The stoichiometry and association constant were two cytochrome C3 molecules per monomer of ferredoxin I and 108 M-2 (at 53 mM ionic strength and $25^{\circ}C$), respectively.

• ALGAE
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• v.19 no.4
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• pp.303-309
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• 2004

The laboratory culture study of Porphyra seriata Kjellman from Korea was conducted at different conditions of temperatures (5, 10, 15, 20, 25 and 30${^{\circ}C}$), photon flux densities (10, 20, 40 and 80 $\mu$mol $^{-2}s^{-1}$) and photoperiods (14L: 10D and 10L:14D). Conchocelis filaments grew fast at 15-20${^{\circ}C}$ and 20-80 $\mu$mol $^{-2}s^{-1}$ under both photoperiods. Concho sporangial branches were produced at 5-25${^{\circ}C}$, and abundant when the conchocelis filaments were cultured at higher temperatures of 20-25${^{\circ}C}$ under both photoperiods. Foliose thalli grew well at 15-20${^{\circ}C}$ under 10L:14D and at 20${^{\circ}C}$ under 14L:10D. At 30${^{\circ}C}$, the foliose thallus failed to survive. No archespores were observed at any culture conditions. Spermatangia and zygotosporangia were formed in squarish patches at the upper marginal portion of mature thalli. Anatomical examination revealed that the mature spermatangia were 64 (a/4, b/2, c/8) and 128 (a/4, b/4, c/8), and that of zygotosporangium was 16 (a/2, b/2, c/4) according to the Hus' formula.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.30 no.2
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• pp.71-77
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• 1994

A serious of study is carried out to practical use of the three-slot cambered otter board improved by the authors. As the first step, we designed main plates, slots and accessories, such as holding plate, fan-shaped towing plate, normans, center ring, etc. Standing on this design, we made the simple cambered and three-slot cambered model otter board with accessories in a linear scale 6:1. and carried out model test to examine the efficiency of these boards. The obtained results can be summarized as follows: 1. On the simple cambered board with accessories, the values of the maximum shear coefficient($C _{LX}$ ). drag coefficient(($C _{D}$) and hydrodynamic efficiency($C _{L}$/$C _{D}$ ) are 1.39, 0.56, 2.48 at $22^{\circ}$ of the angle of stall respectively. 2. On the three-slot cambered board with accessories, $C _{LX}$/$C _{D}$ and $C _{I}$/$C _{D}$ are 1.67, 0.92, 1.82 at $32^{\circ}$ of the angle of stall respectively. 3.$C _{LX}$ of board with accessories is smaller 10~12% than that of only the main plate, and the angle of stall is almost same. 4. $C _{LX}$ and the angle of stall of the three-slot cambered board with accessories are greater 20% and $10^{\circ}$ than that of the simple cambered board respectively.

• Journal of the Korean institute of surface engineering
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• v.25 no.5
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• pp.235-252
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• 1992

(Ti, Al)N films were deposited on 304 stainless steel sheet by D.C. magnetron sputtering using Al target and Ti plate. The high temperature oxidation of (T, Al)N films with the variation of composition has been investigated. The chemical composition of (Ti, Al)N films with the variation of composition has been investigated. The chemical composition of (Ti, Al)N films was similar to the sputter area ratio of titanium to aluminum target by means of EDS and AES survey. The high temperature oxidation test of (Ti, Al)N showed that (Ti, Al)N has better high temperature resistance than TiN and TiC films. TiC films were cracked at 40$0^{\circ}C$ in air TiN films quickly were oxidised at $600^{\circ}C$, were spalled more than $700^{\circ}C$. But (Ti, Al)N films are relatively stable to$ 900^{\circ}C$. The good resistance to high temperature oxida-tion of (Ti, Al)N films are due to the formation of dense Al2O3 and TiO2 oxide layer. Especially, Al2O3 oxide layer is more important. The results obtained from this study show, it is believe that the (Ti, Al)N film by D.C. magnetron sputtering is promising for the use of high temperature and wear resistance mate-rials.

• KSBB Journal
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• v.23 no.5
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• pp.375-380
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• 2008

We made an experiment of keeping extension of raw and semi-dried flounder (Pleuronectes herzensteini). Effect of with(WG) or without gill (OG), drying degree (20% drying：20D, 40% drying：40D) and storage temperature (5 and $10^{\circ}C$) and 0.1% chitosan-ascorbate (CA) treatment of vacuum packaging flounder on growth of contaminated microorganism during storage for 10 days were investigated. Total aerobacter (TA) in the OG-treated raw flounder was $0.3{\sim}0.5$ log cycle lower than that of WG-treated flounder and also, number of coliform (CF) and E. coli (CO) in OG were lower compared with WG. Number of TA,. Especially, the TA was $0.42{\sim}1.20$ log cycle lower compared with raw flounder. The TA of the raw flounder stored at $5^{\circ}C$ compared to $10^{\circ}C$ was $0.6{\sim}1.3$ log cycle lower. The growth of total aerobacter, coliform (and E. coli separated from raw flounder in tryptic soy broth were completely inhibited by 0.1% CA. But the growth of TA in the raw and 20% dried flounder was 1.5 log cycle inhibited by 0.1% CA, and the growth of CF and CO were also slightly inhibited. We did value raw sample that treated CA 0D and 20D, and did vaccum packaging at the $10^{\circ}C$ for 10 days, Sensory quality such as appearance, freshness, and texture and overall acceptability after cooking of the 0.1% CA-treated raw and 20% dried flounder were evaluated from good to very good, while CA non-treated products were evaluated to moderate.

• Journal of the Korean Chemical Society
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• v.29 no.2
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• pp.104-110
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• 1985

Empirical force-field method has been applied to D-sorbitol, the crystal structure of which has been studied by the single crystal X-ray and neutron diffraction analyses. The calculated C-C bond lengths agree with those observed within 0.009${\AA}$. The C-O bond lengths show a larger deviation of 0. 023${\AA}$. The calculated C-C-C and C-C-O valence angles agree with those observed within $2.3^{\circ}$ and $1.9^{\circ}$respectively. Because torsion angles are influenced by packing forces, they show considerably flarger r. m. s. deviations. Calculations of the conformational energies of the model compound at selected C(1)-C(2)-C(3)-C(4) torsion angles made with the program MMI, produced result that the prediction of the observed preferred conformation of the carbon chain appeares to be less satisfactory.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.1
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• pp.106-117
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• 2001

This article is to study the risk factors of odontogenic infection which includes not only dental decays but also gumboils and cellulitises. 7936 young patients who visited the department of pediatric dentistry, Dental Hospital of Yonsei University from Jan 1st 1991 until Dec 31st 1992 were reviewed and statistically analyzed. The results are: 1. Frequencies of the source of odontogenic infection are ordered from high to low: Gumboil Upper A>D>B>C Lower D>E>A>D Cellulitis Upper D>A>E>B>C Lower D>E 2. There was no statistically significant relationship between odontogenic infection and seasonal weather change.

• Korean Journal of Plant Taxonomy
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• v.32 no.4
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• pp.481-489
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• 2002

Unrecorded fern species of Korean flora, Thelypteris interrupta (Willd.) K. Iwats. (Thelypteridaceae) and Dryopteris subexaltata (H. Christ) C. Chr. (Dryopteridaceae), were collected from Jeju island off the south coast of Korean peninsula and reported here. T. interrupta is most similar to T. acuminata (Houtt.) C. V. Morton in morphology, however, the two species are readily distinguishable by the plant color including rhizome, stipe base and spore, and the presence of glandular hair as well as the distribution pattern of sorus on lower leaf surface. D. subexaltata is also well distinguishable from its relatives, D. sparsa (D. Don) Kuntze, D. sabaei (Franch. & Sav.) C. Chr., and D. yakusilvicola Sa. Kurata by the presence of proliferation, shape of pinnae, distribution pattern of sori on lower leaf surface, and shape of indusium.

• Korean Journal of Environmental Biology
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• v.33 no.2
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• pp.248-255
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• 2015

Induction of regeneration and maturation of the free-living gametophytes of Saccharina japonica was studied at four temperatures (5, 10, 15 and $20^{\circ}C$), four levels of irradiance (5, 10, 20 and $40{\mu}mol\;m^{-2}\;s^{-1}$) and three photoperiods (14 : 10, 12 : 12 and 10 : 14 h L : D). Female gametophyte fragments were maintained in active regeneration without reaching sexual maturity under conditions of $15^{\circ}C$, $20{\mu}mol\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D), whereas the conditions for male gametophytes were slightly different at $15^{\circ}C$, $5{\mu}mol\;m^{-2}\;s^{-1}$, 14 : 10 h (L : D). The sexual maturation of female and male gametophytes took place under $5^{\circ}C$, $20{\sim}40{\mu}mol\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D) and $15^{\circ}C$, $40{\mu}mol\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D), respectively. These results provide basic information for controlling the regenerationand maturation of free-living gametophytes for strain improvement and cross breeding of S. japonica.