• 한국해양학회지
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• v.27 no.3
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• pp.197-209
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• 1992

The distribution pattern of macrobenthic polychaete worms and their feeding guild structures were investigated along the coastal region off Kunsan (southeastern Yellow Sea) during the winter season. The polychaete worms, the most dominant infauna, comprised 54 species in 30 families and showed their mean density of 300. indir./m$^2$). Dominant species in the study area were Stermaspis scutata, Lumbrineris cruzensis, Notomastus sp., Nephtys polybranchia, Praxillella affinis. Polychaeres were assigned to 12 feeding guilds and BMX (burrowing, motile, muscular pharynx) was the most dominant feeding guild (26%). Muddy sediments sustained more polychaete worms which showed burrowing (65%), motile (72%), and non-tentaculate strategies (92%), while sandy sediments contained more filter feeders (32%) and sessile (63%), and more tentaculate worms (49%). The sediment grain size was suggested to be the prime factor selecting the polychaete feeding guild.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.196-200
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• 2002

In order to identify the feeding stimulants for flatfish, the feeding tests were conducted using some diets added the amino acids, nucleotides, betaine and TU and acid hydrolysates to basal diet formula, respectively, The feeding stimulant activities and synergistic effects of those compounds were evaluated by a bioassay method. The KH, a kind of acid hydrolysate, possessed a remarkable feeding stimulant activity. It's stimulant activities were increased up to the concentration of $1.05\%$ (w/v), and were independent of pH. The formulation of KH and glycine had a most synergistic effect, The feeding rate of diet with feeding stimulation was 1,4 fold than that of diet without one. The costs for optimum formulation of feeding stimulants were cheaper than some additives in diets. It suggest that the results can practically used in preparation of diet containing feeding stimulant effects for flatfish.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.467-477
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• 2009

Host preference was tested on the 7 species plants against ggot-mae-mi, Lycorma delicatula (Hemiptera: Fulgoridae). This insect highly preferred Ailanthus altissima and Vitis vinifera however, didn't choose the other plants preferentially. Both nymphs and adults lived longest in A. altissima and V. vinifera but lived in short and low ecdysis rate against other plants and 3 species fruits. By analyzing the phloem-feeding behavior using EPG, L. delicatula was showed the short time in non-probing phase and it also exhibit the longest feeding time in A. altissima and V. vinifera, but other plants did not feed the phloem at all. In sugar contents analysis, A. altissima existed high sucrose proportion and followed by fructose>glucose, V. vinifera was analyzed by an order of glucose> fructose>maltose>sucrose>rhamnose, Malus pumila was as glucose> fructose, Pyrus calleryana was as glucose>unkown>fructose, Hibiscus syriacus was as sucrose>glucose. Nymphs and adults of L. delicatula lived longest in 5% sucrose solution, and next is in 5% fructose solution. However, they lived short in other sugar solutions. L. delicatula nymph and adult according to the combination of sugar proportion found in original plants lived longer in sugar combination solution of A. altissima and those of V. vinifera was next. Analyzed original sugar proportion from M. pumila, P. calleryana, H. syriacus respectively, L. delicatula lived short period comparing to the A. altissima, V. vinifera. This result was judged that sugar contents affected on choosing the host plants.

• Journal of Sericultural and Entomological Science
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• v.28 no.2
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• pp.38-47
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• 1986

Silkworm(Bombix mori) were reared with modified artificial diets which were mixed with, as additives, leaf powders of Erigeron canadensis L., Cassia tora L., Cyperus anuricus Var.Laxus and Vigna Sinensis NEDL. The effects of additives on silkworm characteristisc of tested plants were summarized as follows ; 1. About 2-5% addition on dry weight base of leaf powders of E. canadensis, C. tora, C. anuricus or V.sinensis to the basic artificial diet promoted feeding response and digestion and resulted in good practical silkworm characteristics. The addition of V.sinensis and C.anuricus showed especially good effects. 2. The syneristic effect between different plant species was not recognized based on the feeding response and digestion of silkworm reared with various combinations of 2-4 different plant additives. 3. Electrophoretic zymograms of estrase, protease and phosphatase on haemolymph, intestine and silkgland were significantly different among treatments. In general, 1 or 2 more electrophoretic bands were detected when feeding response and digestion were promoted. 4. Contents of starch, crude fat, crude protein and inorganic base were apparently higher in the tested plants than in mulberry leaves. However, no volatile ingredent which is directly realted with feeding response was identified.

• Korean Journal of Cognitive Science
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• v.25 no.2
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• pp.73-90
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• 2014

It has been suggested that primates' trichromatic color vision is an adaption for folivory and frugivory. Ripened fruit frequently is red against a green background. Given this, the question for our research was whether the ecological relationship between red and green plays any role in figure-ground organization that is an essential step in forming our perception of objects? In this study, it was tested which color looked most strong as a figure, using a red circle on a green background and a green circle on red background. The results of Experiment 1 showed that most participants saw the red circle for the figure more than the green circle. However, this effect was significant only in females, but not in males. Accordingly, this result suggests that the visual development of figure-ground organization based on red-green color combination may differ between males and females. In Experiment 2, it was surveyed that the results of Experiment 1 was simply not by the sex difference of color preference. The gender difference of the figure-ground organization on red-green stimuli are discussed in terms of some recent hypotheses such as gatherer-hunter hypothesis.

• Ocean and Polar Research
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• v.26 no.2
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• pp.367-376
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• 2004

Macrobenthos were collected at 7 stations located from $5^{\circ}N$ to $10^{\circ}N$ with 1o interval along the longitude of $131^{\circ}W$ using a box corer with sampling area of $0.25\;m^2$ in July, 1999. In order to see the vertical distribution of macrobenthos in sediments, each subcore sample was divided into 5 layers with 1 cm interval up to 6 cm depth. Each subcore sample was sieved through 0.3 mm mesh screen and fixed with 10% Rose Bengal added formalin. A total of 22 faunal groups in 11 phyla were sampled and the average density was $959\;{\pm}\;584\;ind./m^2$. Foraminiferans comprised 34.8% of total specimens were the most abundant fauna, and followed by nematodes (27.5%), polychaete worms (15.7%), and benthic harpactoid copepods (10.4%). A latitudinal trend was shown in the distribution of macrobenthos; the maximum density of $1,832\;ind./m^2$ appeared at station N06 and the most poverished community occurred at station N09 with the density of $248\;ind./m^2$. The density of typical macrofaunal taxa except foraminiferans and nematods was $116\;ind./m^2$. In the vertical distribution of macrobenthos, more than 70% of macrobenthos occurred in the upper 2 cm layer, and upper 4 cm layer contained about 90% of macrofauna. Polychaete worms consisted of 22 families, and cirratulid and paraonid worms were dominant polychaete species. The prominant feeding guilds of polychaete worms were SDT (surface, descretely motile, tenaculate feeding) and SMX (surface, motile, non-jawed); they comprised more than 50% of polychaete abundance. These feeding guilds of polychaete worms suggests that the deep sea benthos should be well adapted the newly settled deposits from water column, but this should be clarified by the further studies.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.1
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• pp.40-49
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• 2004

An ecological study on a sea urchin population, Strongylocentrotus nudus, a key role species in recovery of macroalgal bed, was conducted in Hosan, Samcheok area on the east coast of Korea. Three experimental plots, namely, AMB (artificially-restored macroalgal bed), BG (barren grounds) and NMB (natural macroalgal bed) were established after a pilot survey in June 2002. Distribution and abundance, grazing rates, predation pressure and predator guilds on S. nudus were estimated in three plots bimonthly from Aug. to Dec., 2002. Abundance of S. nudus was lowest, but median test diameter of the urchin was highest (Kruskal-Wallis test, p-value, p<0.001 in Aug. and p=0.003 in Oct.) in NMB In-situ grazing rate of S. nudus estimated by enclosure cage experiment in NMB was about 12 times higher in Aug. (160.0 mg seaweed/g sea urchin/day) than in Oct. (13.8). Predation intensity measured by tethering experiment was higher in NMB. Most of the predators on S. nudus were invertebrates and no fish predators were found. Predator guilds identified by the fish trap experiment using live or dead sea urchins included who]ks Neptunea arthritica, starfish Asterina pectinifera, hermit crabs Pagurus of. samuelis, Paguristes barbatus, brown shawl crabs Atergatis integerrimus and crabs Actaea subglobosa. High predation pressure on S. nudus in natural macroalgal beds was the likely cause of its low density. Elevated sea urchin density and the consequent lasting deforestation of macroalgae in barren grounds demonstrate the importance of predation pressure on sea urchins.

• Korean Journal of Animal Reproduction
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• v.25 no.4
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• pp.389-397
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• 2001

Cocaine-amphetamine regulated transcript (CART), a satiety factor regulated by leptin, is associated with food intake and motor behavior. In knock out studies, Leu34Phe mutation of human CART gene resulted in obese phenotype but mice carrying a targeted deletion of the CART gene exhibited no dramatic increase of body weight on normal fat diet. To establish a new transgenic mouse model for determining the function of CART on feeding behavior in vivo, we constructed the fusion gene, CART gene under the control of neurofilament light chain promoter, which regulates gene expression at the stage of neuronal differentiation. Transgenic mice were generated by microinjection method and screened by PCR and Southern blot analyses. In these transgenic mice, overexpression of CART was detected by in situ hybridization in spinal cords and brains at 13.5 days post-coitum embryos. At six weeks of age, RT-PCR analysis showed that exogenous CART mRNA was expressed strongly in brains and spinal cords, but not much in other tissues. Our results suggest that these transgenic mice provide a new model to investigate the function of CART gene in neuronal network associated with feeding behavior.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.572-580
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• 2000

Community structure of macrobenthos was studied in Chinhae Bay, a southern coastal area of Korea. Sampling was conducted bimonthly using a Smith-McIntyre grab ($0.05 m^2$) at eight stations from January to November, 1998. A total of 237 species were sampled. It was comprised of annelids ($80 spp. 33.8{\%}$), arthropods (80 spp.), molluscs (47 spp.), echinoderms (16 spp,) and others, Mean density of individual was $1,939 ind./m^2$ and mean biomass was $171.6 gwwt/m^2$. Annelids were a density-dominant faunal group with a mean density of $1,533 ind./m^2$ which occupied $79.0{\%}$ of the total individual of benthic animals. Molluscs were represented as a biomass-dominant group with a mean biomass of $95.9 gwwt/m^2$ ($55.9{\%}$ of total biomass). The major density-dominant species were a bivalve Theora fratilis ($110 ind./m^2$) and five species of polychaetes, Lumbrineris longifolia ($417 ind./m^2$), Chaetozone setosa ($145 ind./m^2$), Sigambra tentaculata ($128 ind./m^2$), Cirratulus cirratus ($128 ind./m^2$), and Paraprionospio pinnata ($103 ind./m^2$). Cluster analysis showed that the study area could be divided into two station groups and two stations. According to the feeding guild of polychaetes, four feeding guilds were found, and the major ones were surface deposit-feeders, burrowing deposit-feeders, surface suspension-feeders, carnivore.

• Korean journal of applied entomology
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• v.55 no.2
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• pp.81-89
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• 2016

Double-stranded RNA (dsRNA) has been applied to control insect pests by its suppressive activity against specific target genes. Integrin is a heterodimer (${\alpha}$ and ${\beta}$) transmembrane protein and plays a critical role in cell-to-cell or cell-to-extracellular matrix interactions in eukaryotes. Suppression of ${\beta}$ subunit integrin gene expression by its specific dsRNA (= dsINT) induces significant mortality against target insects. Furthermore, a recombinant bacterium expressing dsINT is potent to kill target insects. However, it is necessary to develop a formulation technique of the dsRNA-expressing bacteria to apply the bacterial insecticide against field populations. This study formulated the recombinant bacteria by freeze-drying and tested its control efficacy against target insects. The formulation maintained significant insecticidal activity against last instar larvae of Spodoptera exigua. While a commercial Bacillus thuringiensis (Bt) insecticide exhibited only about 60% insecticidal activity against S. exigua last instar, an addition of the dsINT-expressing bacterial formulation significantly enhanced the Bt insecticidal activity. The dsINT-expressing bacterial formulation exhibited relative selectivity to target insects depending on sequence similarity. These results indicate that a freeze-dried form of dsRNA-expressing bacteria keeps its insecticidal activity.