• Ocean and Polar Research
• /
• v.36 no.2
• /
• pp.189-197
• /
• 2014

The pearl-spot damsel, Chromis notata, is one of the important fishery species in Korea. While C. notata has been commonly harvested in southern Korea, the increasing number of C. notata in higher latitudes has crucial ecological, economic and evolutionary implications under conditions where the climate is rapidly changing. Here we examined the morphological and genetic characteristics of C. notata to assess patterns of geographical variations among the groups from three different sites. The groups were clearly distinguishable in the analysis of morphological characteristics. On the other hand, the groups were genetically indistinguishable. All individuals fell within a single clade in the neighbor-joining tree but appeared scattered in the haplotype network. Several haplotypes are shared among the sampling sites (Jejudo-Ulleungdo; Hap 9, Wangdolcho-Ulleungdo; Hap 28, Hap 33, Hap 34). Although control region markers did not elucidate the spatial patterns in genetic characteristics, Wangdolcho and Ulleungdo groups appear to exhibit a more robust gene flow between the two groups than with Jejudo group. Integrative approaches such as those combining morphological and genetic analyses minimize potential errors caused by limited perspectives of each analysis and can provide useful information for discovering functional DNA regions attributable to morphological characteristics expressions.

• Applied Microscopy
• /
• v.28 no.3
• /
• pp.273-282
• /
• 1998

Ultrastructure of fertilized egg envelope in the tomato clown anemonefish (Amphiprion freatus) was examined by mean of light, scanning and transmission electron microscopies. The fertilized egg of tomato clown anemonefish was of non-transparent, ellipsoidal, adhesive and non-floted type, and there were numerous oil droplets in the yolk sac and adhesive filaments in the area of the animal pole. The outer surface of egg envelope was smooth. The fertilized egg envelope consisted of two distinct layers; a non-adhesive outer electron-dense layer and an inner layer, consisting of five horizontal low electron-dense lamellae alternating with the middle electron dense interlamellae.

• 월간낙농육우
• /
• v.35 no.11
• /
• pp.122-127
• /
• 2015

충북 청주시 흥덕구 오송읍. 산기슭 자락에 자리 잡은 기동목장(대표 남기동 현병숙)에는 여느 목장들과는 다른 특별함이 있다. 소들이 밥을 먹기 위해 걸어 나오면 선풍기가 소를 따라 방향을 틀어 시원하게 밥을 먹을 수 있도록 돕고, 소들이 휴식을 취하기 위해 운동장으로 이동하면 선풍기는 소들을 뒤따른다. 우사 천정은 흡사 돔구장을 보는 듯 자동으로 열렸다 닫혔다를 반복하고 혹여나 소가 넘어질까 바닥은 홈을 파놓았다. 하나부터 열까지 소들의 안전을 위주로 모든 것이 짜여 있는 이곳을 두고 목장주 남기동 대표는 이것은 특별함이 아닌 사소한 관심이라고 말한다. 남기동 대표는 "우리 목장은 그저 다른 목장들과 같은 평범한 목장인데 단지 다른 점이 있다면 틈틈이 설치한 편의시설들과 시설관리를 위한 장치들" 이라면서 "누구나 관심을 갖는다면 쉽게 설치할 수 있는 것들이라 내보이기도 부끄럽다"고 말했다.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.33 no.6
• /
• pp.391-399
• /
• 2020

In this study, the behaviors of a suction cap shaped as an arch were analyzed using finite element models. The fundamental structural behaviors of both flat- and arch-type caps were compared, and the advantages of the arch-shaped cap were explained. Moreover, the effects of geometric parameters and stiffener arrangements on the stress and deformation of the arch-shaped caps were investigated by comparisons of the changes in the behaviors of the caps. Additionally, the effects of boundary condition at the edge of the cap were analyzed to study the interactions between the cap and cofferdam walls; these results were used to derive the fundamental structural design of stiffened arch caps. Unlike flat caps, the results showed that ring stiffeners could improve the structural behaviors of arch caps remarkably, while the contributions of the radial stiffeners to the structural behaviors of the caps are dependent on constraints at the edges of the caps.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.57 no.2
• /
• pp.153-168
• /
• 2024

Morphological and skeletal development in the cultured threeline grunt Parapristipoma trilineatum was studied from 1.96 to 61.39 mm notochord length (NL) or standard length (SL) specimens (n=360). After two days post-hatching (dph, 2.13 mm NL), the mouth opened, and melanophores formed in the eyes and egg yolk were absorbed. Oli globules were absorbed at 3 dph (2.71 mm NL). The total number of fin rays reached that of adults at 28 dph (10.58 mm SL). During skeletal development, the premaxillaray, dentary, opercle, preopercle, and cleithrum first began to ossify at 6 dph (3.51 mm NL). Ossification of all skeletal elements was completed at 28 dph (14.57 mm SL). The vertebrae began to ossify at 17 dph (5.63 mm SL) and were completed at 28 dph (8.48 mm SL), progressing from cranium to caudal bone. The centrum ossified from the dorsal to ventral direction. Vertebral fusion and separation were found to be common skeletal abnormalities.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.19 no.4
• /
• pp.312-320
• /
• 1986

The taste compounds in low salted and fermented damsel fish, Chromis notatus, substitute lactic acid, sorbitol and ethyl alcohol for sodium chloride and fatty acid composition were analysed during fermentation. The best organoleptic result was obtained after 60 days fermentation. Volatile basic nitrogen (VBN) was increased significantly until 10 days fermentation period but low salted and fermented products ($8\%\;and\;10\%$ salted) gave lower VBN value than that of $20\%$ salted after 85 days fermentation. Amino nitrogen also increased rapidly after 10 days fermentation and slowed down up to 60 days but it was decreased after 85 days. The abundant amino acids in raw damsel fish were lysine, taurine, aspartic acid, glutamic acid, proline and alanine and those were consisted of $58.8\%$ of the total free amino acids but arginine and tyrosine were trace in content. After 60 days fermentation, lysine, glutamic acid, alanine, leucine, aspartic acid and valine were dominant which marked $58{\sim}71\%$ of the total free amino acids but taurine was not detected. In raw ingredients, IMP was abundant which marked $18.6{\mu}mole/g$ while in fermented sample, hypoxanthine was predominant but ATP and ADP were not detected. During fermentation TMA was increased but TMAO was decreased which marked only trace after 60 days. Total creatinine was rapidly increased after 10 days but notable change was not showed after 60 days fermentation. The major fatty acids of total lipid in raw and fermented damsel fish were 16:0, 18:1, 16:1, 22:6 and 20:5 in order.

• Journal of the Korean earth science society
• /
• v.43 no.6
• /
• pp.737-748
• /
• 2022

In this study, the composition of feldspar phenocrysts observed in the Ulleungdo Albong trachyandesite lava dome was identified by performing point and X-ray element mapping surface analysis (EPMA). Plagioclase, which appears as a phenocryst in the Albong trachyandesite, corresponds to bytownite and labradorite, and andesine, and lath in the microphenocrysts and the matrix corresponds to andesine to oligoclase. Alkali feldspar mantled around plagioclase phenocrysts and microphenocrysts correspond to anorthoclase and sanidine. Plagioclase phenocrysts with a distinct zonal structure represent a normal structure in which the An content of the zoning decreases from bytownite to labradorite or andesine as it moves from the center of the phenocrysts to the edge. The edge of the phenocryst is surrounded by alkali feldspar, showing an antirapakivi texture. X-ray mapping of feldspar phenocrysts showed a typical antirapakivi texture. Normal zoning with distinct zoning showing a difference in component composition was clearly shown. The edges were mantled with alkali feldspar, and antirapakivi represents the texture. The antirapakivi texture of feldspar in the Albong trachyandesite may have been formed in the mixing system when alkali feldspar crystallized and mantled around plagioclase phenocrysts and microphenocrysts. This is because plagioclase phenocrysts and microphenocrysts in magma that had already crystallized are more mafic than trachyandesite magma.

• Applied Microscopy
• /
• v.41 no.2
• /
• pp.123-128
• /
• 2011

The micropyles on the prefertilized and artificial fertilized eggs of Epinephelus fasciatus were investigated using scanning electron microscope (SEM). The micropyles ($6.6{\pm}0.41\;{\mu}m$) of E. fasciatus eggs were found in the animal pole and theirs shape were observed as a flat crateriform of cylindrical shape. The micropylar vestibule arranged by 6~7 thickened spiral annuli on the ridge and contributed to differentiate and form fertilization cone for blocking to polyspermy by presenting swollen vestibule structure. As E. fasciatus eggs was pelagic, so chorionic surface was an uneven structures such as circular and fillar form nodules. Especially, various pores (0.15~0.55 ${\mu}m$, 230~270 pores) distributed at the only around micropyles, those pores radiately exhibited regular projection structures showing gill filament-shape. These ultrastructural characters of E. fasciatus eggs can be utilized in a taxonomical cue of grouper species.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.32 no.3
• /
• pp.295-302
• /
• 1999

To study the distribution of ichthyoplankton in the adjacent waters of Yousu, ichthyoplankton were sampled 4 times (September 1996, November 1996, February 1997 and May 1997). Four species of fish eggs and twenty-four species of fish larvae were identified. Among fish eggs, Engraulis japonicus eggs were the dominant species comprising $80.6\%$ of the total fish eggs collected, followed by Callionymidae spp. $1.6\%$, Konosirus punctatus and Maurolicus muelleri occupied below $1.0\%$ respectively, while $17.8\%$ were unidentified. Most larval fish species were found in September (17 species). In fish larvae, Callionymidae spp. was the dominant species occupying $25.7\%$ of total fish larvae collected and than followed by Gobiidae spp. $23.5\%$, Sillago japonica $17.2\%$ Engraulis japonicus $12.2\%$, Omobranchus elegans $9.9\%$ and the unidentified species were less than $2.0\%$. The larvae fish species collected in this study area were comprising the coastal sedentary species (Gobiidae, Callionymidae, Hexagrammos otakii and io on), and the warm water species (Auxis spp. and Coryphaena hipurus and Pomacentridae spp.) which were appearing by warm water current flowing near the costal area of Cheju Island.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.49 no.2
• /
• pp.117-125
• /
• 2023

In this study, the anti-inflammatory and anti-oxidative activities were compared for the extracts of non-fermented Ligustrum japonicum fruits (LJF) and fermented counterparts. U se of Latilactobacillus curvatus (L. curvatus) and Weissella minor (W. minor), isolated from the Jeju Chromis notata, as fermented strains led to the extracts of LJF-LC and LJF-WM in this experiment. The yield of each fermented extract (LJF-LC and LJF-WM) was 40.5 ~ 46.0%, higher than 29.5% of non-fermented extract (LJF). As a result of an activity experiment using RAW 264.7 macrophages stimulated by lipopolysaccaride (LPS), it was confirmed that LJF-WM, a fermented extract, has an excellent effect of inhibiting NO production in a concentration-dependent manner without cytotoxicity. Upon the screening of DPPH and ABTS⁺ radical scavenging activities, the fermented LJF-LC and LJF-WM showed comparable to the non-fermented LJF. In the study of cell protection effect using HaCaT keratinocytes damaged by hydrogen peroxide (H₂O₂), the fermented LJF-WM indicated protective effect against oxidative stress. In addition, quantitative analysis of a major constituent salidroside by HPLC indicated about 15.6 mg/g for the LJF-LC and 13.9 mg/g for the LJF-WM, which were higher than that of non-fermented LJF (12.0 mg/g). Based on these results, it was suggested that the fermented extract from L. japonicum fruits could be used as a natural cosmetics material with anti-inflammatory and anti-oxidative effects.