• Korean Journal of Ichthyology
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• v.32 no.3
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• pp.136-142
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• 2020

Morphology and osteology of the slender ribbonfish, Trachipterus ishikawae was described and figured in detail. The morphological characteristics are as follow: body elongate and compressed; upper jaw protrusile; tubercles along ventral edge of body and tail; eyes are large; body naked; caudal fin long and at a right angle to the body; from (3~4)+(7~8) gill rakers; from 180 to 185 dorsal fin rays, from 12 to 13 pectoral fin rays; 9 caudal fin rays and 5+2 short spine at caudal spine. The osteological characteristics are as follow: premaxillary is long and has four teeth; dentary is triangle shape; interopercle and subopercle are wide and flat; 5 branchiostegal rays; post clavicle is thin and long; from 79 to 80 centrum; posterior vertebrae elongate; 5~6 tubercles at urostyle bone.

• Parasites, Hosts and Diseases
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• v.34 no.4
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• pp.283-285
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• 1996

Six metacercariae were found from the gill filaments of Conger myriaster purchased at Mokpo-shi in korean on September, 1996. Based on the morphology of the excysted specimen. we identified them as metacercariae of Heterophyosis continua, C. myriaster is a new intermediate host H. continua in the literature.

• International Journal of Industrial Entomology and Biomaterials
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• v.20 no.1
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• pp.25-28
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• 2010

Silk fibroin was conjugated with methoxypoly(ethylene glycol) derivatives to prepare silk nanoparicles. Conjugation of SF with PEG was examined with various instrumental analyses. Nuclear magnetic resonance spectrometry and amino acid analysis showed that serine and tyrosine residues in SF were reacted with PEG and resulted in increasing molecular weight. The sizes and shapes of SF nanoparticles observed by transmission electronmicroscope were ranged about 150-400 nm in diameter and spherical morphology. UV/VIS spectrometry showed SF nanoparticles might be outer PEG and inner SF structure.

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.133-140
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• 2019

Two-dimensional (2D) ultrathin molybdenum dichalcogenides $MoS_2$ has gained a great deal of attention in energy conversion and storage applications because of its unique morphology and property. The 2D $MoS_2$ nanosheets provide a high specific surface area, 2D charge channel, sub-nanometer thickness, and high conductivity, which lead to high electrochemical performances for energy storage devices. In this paper, an overview of properties and synthetic methods of $MoS_2$ nanosheets for applications of supercapacitors and rechargeable batteries is introduced. Different phases triangle prismatic 2H and metallic octahedral 1T structured $MoS_2$ were characterized using various analytical techniques. Preparation methods were focused on top-down and bottom-up approaches, including mechanical exfoliation, chemical intercalation and exfoliation, liquid phase exfoliation by the direct sonication, electrochemical intercalation exfoliation, microwave-assisted exfoliation, mechanical ball-milling, and hydrothermal synthesis. In addition, recent applications of supercapacitors and rechargeable batteries using $MoS_2$ electrode materials are discussed.

• Korean Journal of Environmental Biology
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• v.39 no.1
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• pp.6-15
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• 2021

Various biometric and geometric measures were used to discriminate between the morphologically similar river puffer, Takifugu obscurus, tiger puffer, T. rubripes, their hybrids, and their triploid hybrids. The hybrids and triploid hybrids had greater anal fin width, nostril width, and snout length than the parental species (p<0.05). However, they had less caudal peduncle depth, inter-orbital width, head length, and head width(p<0.05). The morphometric and meristic characteristics of the hybrids and triploid hybrids were either intermediate between the parental species or more similar to those of one parental species. However, the external morphology of the hybrids and triploid hybrids was predominantly maternal. The triploid hybrids had asymmetry in the fin rays and gill raker numbers. This study identified phenotypic characteristics by distinguishing the morphological variables of river puffer, tiger puffer, their hybrids, and their triploid hybrids.

• Journal of fish pathology
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• v.34 no.1
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• pp.47-53
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• 2021

Scuticociliates are one of the serious parasitic threats faced by the marine aquaculturists worldwide. To date, Uronema nigricans, Philasterides dicentrarchi, Miamiensis avidus, Uronema marinum, and Pseudocohnilembus persalinus have been reported as the important culprit species causing scuticociliatosis in fish. The present paper reports the finding of an additional scuticociliate isolate from the gill of diseased olive flounder Paralichthys olivaceus in Korea. Based on the morphological characteristics, a scuticociliate in this study was identified as Paranophrys marina. Phylogenetic analysis placed P. marina as a sister lineage to three species of Pseudocohnilembus and Mesanophrys carcini within the order Philasterida.

• Journal of fish pathology
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• v.33 no.1
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• pp.15-21
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• 2020

We found skin flukes in snubnose pompano (Trachinotus blochii) from a public aquarium and attempted clear identification of them to the species level by morphology and molecular analyses. Skin flukes were collected from snubnose pompano showing dyspnea, anorexia and mild hemorrhage on the skin. All the fish samples (n=2) were infected with the flukes on the skin, gill and eyes, covered with excessive mucus. The isolated worms were transferred for making slide specimen and PCR amplification targeting 18S rDNA, 28S rDNA, mitochondrial cytochrome c oxidase subunit 1 (mt cox1) and cytochrome b (Cytb) genes for further analyses. Morphology and measurements data of our slide specimen coincided with those of Neobenedenia girellae. The sequence data of 2 genes (28S rDNA and Cytb) and the phylogenetic trees revealed that our specimen consistently belonged to the N. girellae clade. For 18S rDNA and mt cox1 genes, there was no sequence of either of these 2 Neobenedenia species from the type host available in GenBank. This is the first record of N. girellae in snubnose pompano, but it is still unclear if the snubnose pompano is a natural host for N. girellae or not because N. girellae is known to have an unusual broad host range and the host-switching can occur particularly in captive conditions such as aquarium or aquaculture facilities.

• Toxicological Research
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• v.33 no.2
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• pp.119-124
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• 2017

Hexavalent chromium is a bio accumulative toxic metal in water and fish. It enters aquaculture ponds mainly through anthropogenic sources. Hexavalent chromium concentrations and its effects on the morphology and behavior of Clarias gariepinus were investigated from four aquaculture ponds for 12 weeks. Chromium was measured using diphenyl carbohdrazide method; alkalinity and hardness were measured using colometric method and analyzed with Bench Photometer. Temperature and pH were measured using pH/EC/TDS/Temp combined tester. Temporal and spatial replications of samples were done with triplicates morphological and behavioural effects of the metal on fish were observed visually. Chromium ranged from no detection to 0.05 mg/L, alkalinity 105 to 245 mg/L, hardness 80 to 165 mg/L, pH 6.35 to 8.03 and temperature 29.1 to $35.9^{\circ}C$. Trend in the chromium concentrations in the ponds is natural > earthen > concrete > collapsible. There was a significant difference (P < 0.05) in chromium, alkalinity, water hardness, pH and temperature among the four ponds. Significant positive correlation also existed between alkalinity, water hardness, pH, with chromium. Morphological and behavioural changes observed in the fish include irregular swimming, frequent coming to the surface, dark body colouration, mucous secretion on the body, erosion of gill epithelium, fin disintegration, abdominal distension and lethargy. High chromium concentration in natural pond was due to anthropogenic run-off of materials in to the pond. Acidic pH, low alkalinity, low water hardness also contributed to the high chromium concentration. Morphological and behavioural changes observed were attributed to the high concentrations, toxicity and bio accumulative effect of the metal. Toxicity of chromium to fish in aquaculture could threaten food security. Watershed best management practices and remediation could be adopted to reduce the effects of toxicity of chromium on pond water quality, fish flesh quality and fish welfare.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.71-75
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• 2012

Silk is a natural polymer that has the advantages of the biocompatibility, excellent mechanical strength, low immune rejection, and molding facility. But silk does not dissolve easily in water or general solvent. To investigate the characteristics of silk biological membranes according to dissolving condition of silk fibroin, we made the silk biological membranes using silk fibroin solutions with different amount and dissolving time of silk. The characterizations of the silk biological membranes such as morphology, structure, and mechanical strength were observed. Although each biological membrane has the same fibroin content, there was a significant difference in the thickness and transparency. But there was no significant change in the molecular weight of the silk fibroin solutions and morphology of silk biological membranes. We were established the manufacturing condition for silk fibroin biological membrane. So we expect that the conditions will help in the development of medical supplies in the future.

• Korean Journal of Ichthyology
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• v.6 no.1
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• pp.51-59
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• 1994

Morphology of glochidia of two species of Unionidae mussels, Unio douglasiae and Anodonta woodiana were studied based on SEM, and their attachment on Acheilognathus yamatsutae(Acheilognathinae) was observed in the experimentally infected fishes. The glochidia were round-triangle in shape and possessed larval threads, hooks, hooklets, and sensory hairs. Glochidal attachment and cyst formation of the fish were observed without regard to feeding habit and habitat. Density of glochida on the fish (Acheilognathus yamatsutae) was in the order of pectoral fin, dorsal fin, gill and caudal fin. The host fish became encysted about 5-10 hours to the glochidia, and the glochidia detached about 5-6 days after attachment at water temperature $26{\pm}1^{\circ}C$.