• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.4
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• pp.265-271
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• 1976

Parasitic protozoans of fish, such as Chilodonella, Costia, Trichodina, Ichthyophthirius are effectively eradicated by treating with a mixture of $50\~60\;ppm$ formalin, 0.2 ppm malachite green and 0.6 ppm dipterex in water recycling aquariums. In this case any histopathological changes in the gill of fish were not observed. The parasites began to disappear 6 hours after treatment. Upon increased concentrations of formalin of 130 to 140 ppm, a significant change on the epithelium of gills was observed in $24\~48\;hours $ after treatment. In this case gill epithelium degenerated and necrosis of the gill lamella supporting cells follows.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.430-435
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• 1997

Protopectinases are heterologous group of enzymes that degrades insoluble protopectin which consists of middle lamella between cells of plant tissues. Tissues of potato and carrot could be separated to single cells by addition of protopectinase isolated from Rhizopus sp. Color changes ofthe suspensions treated with protopectinase and mechanically macerated after 2 weeks at 4$^{\circ}C$, were investigated. Color change of the latter was very serious, however, that of the former was insignificant. Furthermore, after heat treatment at 121$^{\circ}C$ for 5min, the constituents of mechanically macerted carrot suspension were separated into two layers, but those of single celled carrot were not. Yields of carrot juices extracted from single celled suspensions and mechanical maceration were 93.6% and 56.0%, respectively. These results support that treatment of protopectinase can increase yield of juices extracted from plant, and manufacture high value-added products in food processing.

• Environmental Analysis Health and Toxicology
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• v.17 no.1
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• pp.7-11
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• 2002

Effects of nonylphenol (NP) on gonadal development and growth of olive flounder, Paralichthys olivaceus were investigated. NP treatment was carried out to fry fish (during 55 to 64 days after hatching) using oral adminstration at nominal NP concentrations of 50, 100 and 150 tig/g BW Gonad before NP treatment was sexually undifferentiated as observed with mostly gonia cells. At 159 days after hatching, ovarian lamella of ovary were filled with oogonia and perinucleolus oocytes. On the other hand, testicular lobules of the testis were occupied by spermatogonia, spermatocytes and spermatids. Histological observation of ovary and testis development was any different between the control and NP treated groups. However, growth was significantly increased in NP treated groups than control groups (P< 0.05). These results considerate that NP has any effect for sex differentiation and gonadal development, but act for early growth in olive flounder.

• Animal Systematics, Evolution and Diversity
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• v.34 no.1
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• pp.3-9
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• 2018

Two species of the genus Isotomurus $B{\ddot{o}}rner$ are newly recorded in Korea; I. bimus Christiansen and Bellinger, and I. plumosus Bagnall. These species are collected from salt marshes near West Sea of Korea. The Korean materials of I. bimus agreed well with the original description by Christiansen and Bellinger from North America, in its peculiar body pattern, with two long ciliated setae on tibiotarsus of hind leg, multisetaceous lateral flap of ventral tube and the presence of a mucronal lateral seta. Isotomurus plumosus is also easily identified from other Isotomurus species by the peculiar colour pattern, and the presence of long maxillary lamella 1 and a mucronal seta.

• Korean Journal of Veterinary Research
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• v.36 no.1
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• pp.131-142
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• 1996

The effect of relative humidity in swine house on swin pleuropneumonia was examined in piglets experimentally infected with Actinobacillus pleuropneumoniae serotype 5. A total of 20 piglet were grown under 30~40%, 41~50%, 51~64% and 65~80% relative humidity chambers after intratracheal inoculation of A pleuropneumoniae. Characteristic fibrinous pleuropneumonia was observed in the pigs grown at the low relative humidity groups. The detailed results were as follows : 1. Growth performance and environment conditions were lower than high relative humidity groups. 2. Characteristic histopathological findings were fibrinous pleuritis and pneumonia accompanied congestion, hemorrhage, thrombosis and edematous change. 3. Antigenic distribution of inoculated bacterium was found mainly in alveolar macrophages or accumulated foci of macrophages adjacent to necrotic area. 4. Characteristic electron microscopic findings were proliferation of type II pneumocyte with increased lamella bodies and activated alveolar macrophages with pseudopods and widening of interstitium.

• Korean Journal of Veterinary Research
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• v.34 no.2
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• pp.369-374
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• 1994

The acute and subacute toxicity of fungicide folpet was evaluated in fingerings of common carp, Cyprinus carpio and goldfish, Carrassius auratus. Dipping of fishes for acute toxicity was performed for a period of 24h, and the TLm value(median tolerance limit) was 1.52 ppm in common carp and 1.45 ppm in goldfish. Severe damages were observed in various organs and among them, clubbing of gill lamella, lytic degeneration and vacuolation of liver cells, and epithelial edema of renal tubules were relatively prominent. The most significant changes were hyperbasophilic foci of liver cells in subacute toxicity test and these can imply the possibility of hepatocarcinogenecity of folpet.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.4
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• pp.18-26
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• 2000

In order to investigate the influencing factors in flotation fractionation, flotations were performed at varied conditions. The selectivity of fines fractionation was mainly affected by long fiber flocculation degree and if there were not sufficient flocculation of long fibers, more loss of long fibers could not be avoided. The amount of flotation rejects were totally dependent on the stability of froth floated on the stock surface. Only small size fines could stabilize the froth as they hindered the drainage of liquid lamella in flotation-froth. More flotation reject and better flocculation of long fibers were two important factors for improving flotation. Changing a flotation flux or an air-mixing ratio to increase the flocculation of fibers increased long fiber ratio in the reject. In order to satisfy the both conditions of reducing long fiber loss and of increasing flotation reject, search of fractionation promoter is needed.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.486-486
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• 2011

금속산화물을 제조하는 방법으로 수열반응은 wire, rod, needle, lamella, flower등 다양한 형상을 화학적으로 합성하는데 널리 이용된다. 또한 금속산화물의 특성은 구조와 형상에 의존하고, 구조와 형상에 따라 촉매, 기능성 첨가제, 초전도체등에 다양한 분야로 사용되어진다. 본 연구는 수열방법으로 각 물질의 염화물과 암모니아수를 출발물질로 사용하였고, ionization 제어를 위해 염화암모늄을 사용하여 각 물질의 전구체를 합성하였다. 형성된 각 물질의 전구체는 열분해를 통해 산화물로 제조하였다. 이들 입자의 형상 및 특성을 확인하기 위해 SEM, XRD, FT-IR, Raman을 사용하여 확인하였다.

• Food Science and Preservation
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• v.1 no.2
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• pp.107-116
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• 1994

This paper was carried out to Investigate changes in the activities of cell-degrading enzymes, cell wall components and cell structure of peach during maturation and storage for valuation of quality. The firmness of peach was decreased during maturation and storage, and was remarkably decreased in Daegubo than Yumyung. Polygalacturonase and $\beta$-galactosidase activities of peach were increased during maturation and storage, and were remarably increased in soft peach and in mature and soft peach, respectively. Contents of alcohol-insoluble substance, cell wall, and total and insoluble pectin of peach were decreased during maturation and storage, but cellulose and soluble pectin were increased. Intracellular space was enlarged during maturation and middle lamella was gradually degraded during maturation.

• Animal cells and systems
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• v.10 no.4
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• pp.175-182
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• 2006

A new halacarid species, Agaue laeviunguis n. sp. from Youngil Bay, Pohang City, South Korea is described. In sharing the character combination of three dorsal setae on PE, lacking dorsal seta anterior to insertion of leg IV, three ventral setae on PE, female PGS adjacent to GF, telofemora devoid of fovea, well developed smooth cerotegumental lamella on all telofemora, presence of accessory process on all lateral claws, long gnathosoma, and a smooth seta on P2 in both sexes, this species resembles A. subglabra Bartsch from Australia. The species, however, is clearly distinguished from A. subglabra by its larger body, claws of tarsi II-IV without ventral pecten, and much more PGS in female. Description of proto- and deutonymphs are also provided.