• Journal of Ginseng Research
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• 제14권3호
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• pp.421-426
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• 1990

Field and laboratory works were conducted to Investigate the life history, ginseng damage and chemical control effect of the field slug, Deroceras varians A. Adams. D. varians laid eggs from April to June, but a small number of eggs were also found from July to September in the field. Most young slugs grew through the slimmer months to maturity by October. overwintered beneath the moist soil surface, and began feeding and egg-laying in the following April. indicating that D varians have a life cycle in a year. Damage of ginseng plants by D. varina occurred mainly from late April to mid May in the 3rd to 5th year ginseng fields with rice-straw mulching. It seems that this damage is caused by the adults in oviposition periods and related to rice-straw mulching of ginseng fields. In the experiment, ethoprop 5% granule and metaldehyde 6% bait showed relatively high effectiveness in the control of D. varians adults. Bordeaux mixture was more effective when the chemical was sprayed after infestation of the slug than before the infestation and when the 6-12 mixture was used.

• 한국동물학회지
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• 제34권3호
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• pp.368-381
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• 1991

한국산 육생민달팽이유(Limaxpouus와 상ciluria hhstoferi)의 체강벽을 배측부, 복측부 및 외투천 등 3부분으로 나누어 관찰하였으며, 그 결과는 다음과 같다. 1, Limaxpouus의 배측부 체강벽은 많은 모지상돌기 형 태의 근조직과 체강벽상피세포로 구성되어 있으나, 복측부 체강조은 많은 수의 중성점액질 형성세포와 근섬유들로만 형성되었다. 2. Incilaria hhstoferi의 배측부와 복측부는 공히 중성점액질 형성세포와 근섬유들로만 형성되고, 체강상피세포는 관찰되지 않았다. 3. Incilorlo jruhstor$\ulcorner$sri의 병투막측 체준벽은 불규칙한 모양의 단층 체강상피세포와 많은 근섬유로 구성되었다.

• 한국동물학회지
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• 제39권2호
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• pp.139-146
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• 1996

A studv on the ultrastructural changes of the hermaprodite duct epithelium in spring and summer specimens of a Korean slug Incirovia fruhstorferi was conducted. In spring specimen, the hermaphrodite duct was 0.3 H 0.2 mm in diameter and seemed to be a little bit abnormal feature, due to shrinkage. The epithelium of the duct was composed of cells containing various-sized vacuoles and their cytoplasm showed high electron density. In summer specimen, the hermaphrodite duct was 0.4 $\times$ 0.23 mm in diameter and seemed to be more voluminous than that of the spring specimen. The lumen of the duct in the summer specimen was lined by a epithelium composed of several cell types such as ciliated cuboidal, pseudostratified cuboidal, ciliated columnar and irregular cells. Phasocvtotic activities of the duct epithelium are observed only in the summer specimen. Both of the duct epithelia in the spring and summer specimens were surrounded by connective tissues at their bases. The results obtained suggest that the duct epithelia of the slugs experience seasonal variation in relation to their reproductive cycles.

• 환경생물
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• 제39권3호
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• pp.399-405
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• 2021

Until now, five species (Meghimatium bilineatum, M. fruhstorferi, Limax flavus, L. marginatus, Deroceras reticulatum) in three genera of families Philomycidae and Limacidae have been reported in Korea. Philomycidae is a family of air-breathing land snails. Meghimatium hongdoensis sp. nov. is described based on its middle size (60-80 mm in body length), its body coloration (dark-red yellow), no dorsal with streaks, its genitalia, and 16rDNA sequence analysis. Specimens of this new species were collected from Hongdo island, Sinan-gun, Jeollanam-do, Korea. This species is only known from the type locality at Hongdo to date. It could be found in high-humidity sites. Meghimatium uniforme (Laidlaw 1937) was the first one reported in Korea. It was also collected from Gageodo island, Sinan-gun, Jeollanam-do, Korea. In this study, morphological characteristics including their radula and genital structures of these two species were described. Preliminary results of mitochondrial 16S rDNA sequencing and phylogenetic analyses indicated that these species belonged to the Korean clade.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제5권2호
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• pp.50-54
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• 2024

On August 21, 2023, the National Institute of Ecology reported the sighting of an invasive slug resembling Limax maximus Linnaeus, 1758. near Bambat Tree Frog Park, Suwon-si, Korea. This slug is known for its aggressiveness. Specimens were collected around the park and from nearby farms. Through barcoding analysis and sequence comparison, it was identified as L. maximus, confirming its presence in Republic of Korea, alongside two previously identified Limax species, Limax flavus Linnaeus, 1758 and Lehmannia marginatus O. F. Müller, 1774. This study represents the first documented report of L. maximus in the country.

• 한국응용곤충학회지
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• 제46권2호
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• pp.325-330
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• 2007

다양한 엽채류에 발생하며 특히 상추에 피해가 큰 민달팽이는 여러 가지 식품자재 중 맥주와 오이즙액에 가장 효과적으로 유인되었다. 하지만, 이들 재료는 민달팽이를 유인할 뿐 살충효과는 전혀 없었다. 민달팽이 유인재료에 살충효과를 나타내는 물질들을 첨가하였을 때 맥주와 담배가루 혼합액의 민달팽이 유인 포살효과가 가장 높았다. 맥주 50ml에 담배 1개비 가루를 혼합하여 작은 플라스틱 용기에 담고 지표면에 매몰한 결과 하룻밤 사이에 평균 25 마리의 민달팽이가 유인 포살되는 것으로 나타났다. 하지만, 민달팽이 유인효과가 높았던 오이즙액에 담배가루를 혼합한 처리구에서는 평균 4.3마리만 유살되었다. 맥주와 담배 혼합액을 민달팽이가 심하게 발생된 상추 재배하우스에 3일간 연속으로 처리한 결과 68.4%의 방제효과를 나타내었으며, 상추 육묘상에서는 58.3%의 방제효과를 보였다. 본 연구에서 개발된 트랩은 매일 작업을 해야 하는 번거로움이 있으나 민달팽이의 피해가 큰 친환경 유기농 채소 생산농가의 육묘장이나 본포장 등 제한된 면적에서는 활용가치가 높을 것으로 기대된다.

• 한국세라믹학회지
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• 제22권6호
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• pp.71-79
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• 1985

In order to fabricate the translucent electrooptic ceramics which are comparable to PLZT, $PNZT^*$ has been prepared from aqueous solutions of their itrate and chlorides. In the quarternary $Pb^{1-x} Nd_x(Zr_{0.63} Ti_{0.37})^{1-\frac{x}{4}O_3$, (PNZT) $(0.02\le x\ge 0.12)$ system cold-pressed PNZT slugs were sintered in $O_2$ in pt-crucible for 45 min. at 118$0^{\circ}C$ and were then heat-treated in air for 60 hrs. at 120$0^{\circ}C$ in Al2O3 crucibles containing $PbZrO_3$ powder to control the atmosphere. Mean particle size of calcined PNZT powders was 0.1~0.15${\mu}{\textrm}{m}$. It was found that the maximum value of optical transmission has been revealed at 6~8 at. % $Nd_2O_3$ added body and that their dielectric constant has been decreased as the frequency increased. Curic temperature has been varied inversely with $Nd^{3+}$ ion content up to 8 at. % and become constant above this value. $^*Pb_{1-x}Nd_x(Zr_{0.63} Ti_{0.37})_{1-2/4}O_3$

• 대한기계학회논문집B
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• 제28권12호
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• pp.1521-1527
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• 2004

Thermocapillary migration of a liquid slug is caused by temperature difference between the ends of a slug. The temperature difference induces the difference of the surface tension coefficient and consequently of capillary pressure between the ends of the slug. Presently available model to predict a velocity of thermocapillary migration adopts the Poiseuille equation which is valid only for a very long slug and neglects the shear stress near the contact line. In the present study, a new model has been developed to consider the shear stress near the contact line so that it can be applied to slugs or drops of general configuration. The experiments using mineral oil with the length to diameter ratio being 10 and a glass capillary were performed. It was found that the liquid slug began to move upon overcoming contact angle hysteresis when the temperature difference reached 35$^{\circ}C$. The results indicate that the new model well predicts the velocity of the liquid slug.

• 한국해양바이오학회지
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• 제2권4호
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• pp.209-223
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• 2007

Nature is one of the most important sources of pharmacologically active compounds in the search for drugs against life threatening diseases. Even though plants and terrestrial microorganisms have played as an important source for the new drug candidates from nature, marine organisms such as tunicates, sponges, soft corals, sea horses, sea snakes, marine mollusks, seaweeds, nudibranches, sea slugs and marine microorganisms are increasingly attracting attention in recent years. Marine organisms also have the potential to develop into future drugs against important diseases, such as cancer, a range of bacterial and viral diseases, malaria, and inflammations. Even though the mechanism of action in the molecular level of most metabolites is still unclear, the mechanisms by which they interfere with the pathogenesis of a wide range of diseases have been reported. The knowledge of this is one of the key factors necessary to develop bioactive compounds into medicines. This is due to their structurally unique and pharmacologically active compounds. The potential pharmaceutical, medicinal and research applications of some of these compounds are discussed in hundreds of scientific papers, and are reviewed here.

• 한국주조공학회지
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• 제20권4호
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• pp.269-276
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• 2000

So far, the study on semi-solid process has been carried out to develop and research new advanced materials without some casting defects. In this study, A356 billets consisted of various dendritic shapes were prepared using electro-magnetic stirring process continuously. As-cast respectively has liquidus temperature of $625.6^{\circ}C$ and solidus temperature of $573.55^{\circ}C$ A356 slugs were reheated homogeneously at different temperatures of 580, 590 and $605^{\circ}C$, followed by squeezing in a mold insulated with applied pressures(0, 25, 50 and 70 MPa). In order to investigate on aging responce for casts, 50 MPa squeezed specimen among all specimens was prepared in aging treatments, which conditions are aging temperature of $160^{\circ}C$ and holding times of 0, 45, 90, 270, 360, 720, 1440 and 2880 min after solution treatment ($540^{\circ}C$ for 10 hr). SSM ingot with the output velocity of 150mm/min appeared more spheroidal shape and fine structure than that with the output velocity of 250 mm/min. According to increasing in reheating temperature, numbers of fatigue cycles, U.T.S and elongation increased at same time.