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Culture Condition and Growth of Larvae of the Mytilus Coruscus Gould (홍합의 사육조건과 성장)

  • Yoo, Sung Kyoo
    • 한국해양학회지
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    • v.4 no.1
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    • pp.36-48
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    • 1969
  • The larvae of Mytilus coruscus were grown at the room temperature of approximately 15.1C under several different sulture conditions, i.e., salinity, population of the larvae, density and kind of food organisms, etc. (1) The egg of Mytilus coruscus obtained in the laboratory measured about 73.0${\mu}$ in diameter. The embryos gradually developed into larvae up to 179.0${\mu}$ shell length with the shell height of 135.9${\mu}$ even in the absence of the algal food. Beyond this size, however, the growth of larvae was considerably retarded, indicating that the better growth could be expected if the food began to be fed four days after spawning. (2) The larvae began settling upon reaching 281.4${\mu}$ to 310.9${\mu}$ in shell length or 264.3${\mu}$ to 301.9${\mu}$ in shell height. When the shell length reaches 322.6${\mu}$ to 337.1${\mu}$, the shell height also reaches about the same, i.e., 321.5${\mu}$ to 346.2${\mu}$. (3) Daily rate of food consumption was determined by the size of the larvae and the species of the algal food. Regardless of the species of food given, the rage of food consumption remained almost the same until the larva reached the straight-hinge stage, and marked variations were found as the larvae grew larger. Daily rate of food consumption was shown as follow; Chaetoceros calcitrans : Y=2.99167e$\^$0.000018243x$\^$2// Cyclotella nana : Y=3.00324e$\^$0.000015481x$\^$2// Monochrysis lutheri : Y=3.000056e$\^$0.000014485$\^$2// (4) Suitable amount of the food to be given was about five times of the consumed food by Mytilus coruscus. (5) When the numbers of the larvae was higher than ten per milliliter, the growth was significantly retarded. (6) Monochrysis lutheri and Cyclotella nana were much better than Chaetoceros calcitrans as the food of Mytilus coruscus, and even the same food organism showed some difference with the age of the organism. (7) Sea water of higher salinity showed the better result in the growth of the larvae and the water with the specific gravity of 1.020 or below was dangerous for the larvae. (8) The mean growth of the larvae of Mytilus coruscus under lavorable condition was shown as follows: shell length 121.8${\mu}$ to 179.0${\mu}$ : Y=119.18+7.42X 196.7${\mu}$ to 322.6${\mu}$ : Y=203.144+7.687X 322.6${\mu}$ to 985.1${\mu}$ : Y=302.5978+11.8356X shell height 86.3${\mu}$ to 135.9${\mu}$ : Y=86.22+6.40X 158.1${\mu}$ to 321.5${\mu}$ : Y=162.998+10.027X 321.5${\mu}$ to 1,215.4${\mu}$ : Y=309.3701+16.258X Relationships between the shell length and shell height were shown as follows: shell length 121.8${\mu}$ to 179.0 : Y=0.83726X-15.79165 196.7${\mu}$ to 322.6 : Y=1.29909X-100.58610 322.6${\mu}$ to 985.1${\mu}$ : Y=1.3536X-101.6806

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Analysis of Antibiotic Resistant Patterns in Conjugant and Transformant of Three ESBL gene Harboring Klebsiella pneumoniae (세 가지의 ESBL 유전자를 가지고 있는 Klebsiella pneumoniae의 유전자접합체와 헝질전환체의 항생제내성분석)

  • Kim, Yun-Tae
    • Journal of Life Science
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    • v.17 no.10
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    • pp.1426-1433
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    • 2007
  • To investigate the antibiotic resistant patterns of the bacteria producing ESBL, we isolated one organism of Klebsiella pneumoniae from a clinical laboratory in Busan. The organism that produces ESBL gene was detected by double disk synergy test and the presence of three ESBL genes (TEM-1, SHV-12, CTX-M-15) was confirmed by polymerase chain reaction and DNA sequencing analysis. To analyse the characteristics of three ESBL genes, we performed transconjugation, transformation and cloning experiment with the organism. The MIC of Klebsiella pneumoniae was revealed that ceftazidime, cefotaxime and ceftriaxone were $256\;{\mu}g/ml,\;128\;{\mu}g/ml\;and\;128\;{\mu}g/ml$ respectively. The MIC of conjugant (E. coli $RG176^{Na(r)}$) af was revealed that ceftazidime, cefotaxime and ceftriaxone were $256\;{\mu}g/ml,\;64\;{\mu}g/ml\;and\;128\;{\mu}g/ml$ respectively. The MIC of transformant (E. cofi $DH5{\alpha}$) was revealed that ceftazidime, cefotaxime and ceftriaxone were $128\;{\mu}g/ml,\;32\;{\mu}g/ml,\;and\;32\;{\mu}g/ml$ respectively, The MIC of cloned organism of SHV-12 gene (E. coli $DH5{\alpha}$) was revealed that ceftazidime, cefotaxime and ceftriaxone were $128\;{\mu}g/ml,\;8\;{\mu}g/ml,\;and\;32\;{\mu}g/ml$ respectively. The results indicated that MIC of conjugant was higher than MIC of transformant and also SHV-12 gene were not resistant against cefotaxime antibiotic.

An experimental study of cutting efficiency of air-driven diamond burs on human tooth (수종 air-turbine 다이아몬드 버의 절삭 효과에 관한 실험적 연구)

  • Hong, Jin-Sun;Yeo, In-Sung;Kim, Sung-Hun;Lee, Jai-Bong;Han, Jung-Suk;Yang, Jae-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.49 no.1
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    • pp.1-7
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    • 2011
  • Purpose: The purpose of this study was to investigate the cutting efficiency of coarse grit diamond burs with air-turbine handpiece on natural tooth. Materials and methods: Four groups of coarse grit diamond bur were selected: Komet (A), Shofu (B), Premier (C), and Mani (D). The extracted maxillary central incisors were used, and ten cuts were made on each specimen, using the rotary diamond burs. The surface of each bur was measured at the upper, middle, and bottom of the bur with confocal laser scanning microscope and imaged with SEM. The data were analyzed with one-way ANOVA and t-test at the significance level of 0.05. Results: The surface roughness was measured. At the A diamond bur, the Sa values were $52.93\;{\mu}m$, $48.32\;{\mu}m$, $46.79\;{\mu}m$, $45.06\;{\mu}m$, and $43.43\;{\mu}m$ for control, test 1, 2, 3, and 4 respectively. The Sa values were $50.68\;{\mu}m$, $45.62\;{\mu}m$, $44.41\;{\mu}m$, $44.10\;{\mu}m$, and $42.46\;{\mu}m$ for B diamond bur, $58.02\;{\mu}m$, $55.53\;{\mu}m$, $52.22\;{\mu}m$, $48.26\;{\mu}m$, and $45.36\;{\mu}m$ for C diamond bur, and $50.11\;{\mu}m$, $46.73\;{\mu}m$, $45.46\;{\mu}m$, $42.58\;{\mu}m$, and $41.80\;{\mu}m$ for D diamond bur. Surface roughness after each bur use showed significant changes, but no significant difference was found in surface roughness change between bur systems. Conclusions: Surface roughness in the same bur system showed significant differences after each tooth preparation. However no statistically significant differences were found in surface roughness between bur systems. The SEM images between control and test 4 showed the abraded particles.

In vitro Screening of Jeju Island Plants for Customerized Cosmetics (맞춤형화장품 소재 개발을 위한 제주 식물 탐색)

  • Yoon, Kyung-Sup;Kim, Mi Jin;Kim, Moo-Han
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.4
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    • pp.1487-1495
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    • 2018
  • In this study, we investigated collagen production and hyaluronic acid production effects for wrinkle improvement test on 50 kinds of land plants and 10 kinds of marine plants native to Jeju Island as a part of developing customized cosmetic materials. Collagen and hyaluronic acid are recognized as major factors affecting skin aging. Cerastium holosteoides var. hallaisanense Mizushima extract ($100{\mu}g/mL$) produced more than 190% of collagen in the extracts of 50 kinds of land plants. Vicia angustifolia var. segetilis K. Koch. extract ($100{\mu}g/mL$) produced more than 160% of collagen. Ftsia japonica Decne. et Planch. extract ($100{\mu}g/mL$), Euonymus japonica Thunb. extract ($100{\mu}g/mL$), Suaeda malacosperma H.Hara extract ($100{\mu}g/mL$), Elaeagnus umbelellata Thunb. extract ($100{\mu}g/mL$), Sedum oryzifolium Makino extract ($100{\mu}g/mL$), Vicia unijuga A. Br. extract ($100{\mu}g/mL$), and Brassica juncea var. integrifolia Sinsk. extract ($100{\mu}g/mL$) showed more than 140% collagen production effect. Among the 10 species of marine plants, Sargassum macrocarpum C. Agardh extract ($50{\mu}g/mL$) produced more than 190% of collagen, and Carpopeltis angusta (Harvey) Okamura extract ($100{\mu}g/mL$), Codiumcoactum Okamura extract ($100{\mu}g/mL$), and Codium tenuifolium S. Shimada, T. Tadano & J. Tanaka extract ($100{\mu}g/mL$) showed more than 140% collagen production. Suaeda malacosperma H.Hara extract ($100{\mu}g/mL$) showed the effect of producing hyaluronic acid more than 140%, and Ftsia japonica Decne. et Planch. extract ($20{\mu}g/mL$) and Wistaria floribunda A.P. DC extract ($100{\mu}g/mL$) showed more than 130% hyalunonic acid production effect. Among the 10 species of marine plants, Peyssonnelia capensis Montagne extract ($100{\mu}g/mL$) was the most effective. Carpopeltis angusta (Harvey) Okamura extract ($100{\mu}g/mL$), Codiumcoactum Okamura extract ($100{\mu}g/mL$), and Codium tenuifolium S. Shimada, T. Tadano & J. Tanaka extract ($100{\mu}g/mL$) showed more than 120% hyalunonic acid production. Jeju resources, which have good collagen and hyaluronic acid production, showed the potential to be applied to solve the skin troubles of customized cosmetics in the future.

Comparison of Thermal Energy Harvesting Characteristics of Thermoelectric Thin-Film Modules with Different Thin-Film Leg Diameters (박막레그 직경에 따른 열전박막모듈의 열에너지 하비스팅 특성 비교)

  • Kim, Woo-Jun;Oh, Tae Sung
    • Journal of the Microelectronics and Packaging Society
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    • v.25 no.4
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    • pp.67-74
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    • 2018
  • Thermoelectric thin film modules were fabricated by electroplating p-type $Sb_2Te_3$and n-type $Bi_2Te_3$ thin film legs with the same thickness of $20{\mu}m$ and different diameters of $100{\mu}m$, $300{\mu}m$, and $500{\mu}m$, respectively. The output voltage and output power of thin film modules were measured and compared as a function of the leg diameter. The modules processed with thin film legs of $100{\mu}m$, $300{\mu}m$, and $500{\mu}m$-diameter exhibited open circuit voltages of 365 mV at ${\Delta}T=36.7K$, 142 mV at ${\Delta}T=37.5K$, and 53 mV at ${\Delta}T=36.1K$, respectively. Maximum output powers of $845{\mu}W$ at ${\Delta}T=36.7K$, $631{\mu}W$ at ${\Delta}T=37.5K$, and $276{\mu}W$ at ${\Delta}T=36.1K$ were obtained for the modules fabricated with the thin film legs of $100{\mu}m$, $300{\mu}m$, and $500{\mu}m$-diameter, respectively.

Biological Activities of Sesquiterpene Lactones isolated from Several Compositae Plants Part 3 -Inhibitory Activity on Nitric Oxide Release and ACAT- (수종의 국화과 식물에서 분리한 Sesquiterpene Lactone들의 생리활성(제3보) -Nitric oxide 방출 및 ACAT 저해활성-)

  • Jang, Dae-Sik;Park, Ki-Hun;Ko, Hack-Lyong;Lee, Hyun-Sun;Kwon, Byoung-Mog;Yang, Min-Suk
    • Korean Journal of Pharmacognosy
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    • v.30 no.1
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    • pp.74-78
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    • 1999
  • Nine sesquiterpene lactones, which were isolated from Hemisteptia lyrata Bunge, Chrysanthemum zawadskii Herbich var. latilobum Kitamura and Chrysanthemum boreale Makino were evaluated for the inhibition upon the nitric oxide release from the Raw cell and for the ACAT (acyl Co A: cholesterol acyltransferase) inhibitory assay. In the nitric oxide release inhibitory experiment, hemistepsin B $(IC_{50}\;=\;0.05\;{\mu}g/ml,\;0.15\;{\mu}M),$ cumambrin B, tulipinolide and costunolide exhibited strong inhibition with $IC_{50}$ values $0.05\;{\mu}g/ml\;(0.15\;{\mu}M),\;0.1\;{\mu}g/ml\;(0.38\;{\mu}M),\;0.2\;{\mu}g/ml\;(0.69\;{\mu}M)$ and $0.2\;{\mu}g/ml(0.86\;{\mu}M),$ respectively. In the ACAT inhibitory assay, angeloylcumambrin B, tigloylcumambrin B, tulipinolide and costunolide exhibited strong inhibition with $IC_{50}$ values $33\;{\mu}g/ml\;(95.4\;{\mu}M),\;22\;{\mu}g/ml\;(63.6\;{\mu}M),\;38\;{\mu}g/ml\;(151\;{\mu}M)$ and $17\;{\mu}g/ml(73.3\;{\mu}M),$ respectively, whereas other compounds did not exhibit significant activity against ACAT above $100\; {\mu}g/ml.$.

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Isolation of 2,4,5-Trichlorophenoxyacetic Acid-Degrading Bacteria (2,4,5-trichlorophenoxyacetic acid 를 분해하는 세균의 분리)

  • Park, Young-Doo;Eum, Jin-Seong
    • Korean Journal of Soil Science and Fertilizer
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    • v.33 no.1
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    • pp.47-51
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    • 2000
  • 2,4,5-trichlorophenoxyacetic acid (2,4,5-T)-degrading bacterial strains were isolated from rice field and field in suburbs of Taejon. Of the total 100 isolates, 19 strains were selected by fast growth on solid minimal media containing 2,4,5-T as a sole of carbon and energy, and they were identified to genus level. 11 strains were identified as Pseudomonas, 4 strains as Acinetobacter, 1 strains were as Alcaliagenes and 3 strains were not identified. Strains MU19 and MU92 which were identified as Pseudomonas were capable of degradation for 4 kinds of chlorinated aromatic hydrocarbons, 2,4-D, 2,4,5-T, MCPA and 3CB. Acinetobacter sp. MU38 showed the highest degradability in liquid minimal media at 48 hours after inoculation, and Pseudomonas spp. MU19. MU57, MU73, and MU92 were able to degrade carbon source at higher rates. As the results Acinetobacter sp. MU38 and Pseudomonas spp. MU19 and MU92 were capable of biodegradation for broad range of halogenated aromatic hydrocarbons, and had higher rates of degradation for 2,4,5-T.

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First Report of Two Nematode-trapping Fungi, Monacrosporium ullum sp. nov. and Arthrobotrys amerospora, from Korea

  • Kim, Dong-Geun;Ryu, Young-Hyun;Hwang, Hyung-Gue
    • The Plant Pathology Journal
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    • v.22 no.2
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    • pp.174-178
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    • 2006
  • Monacroporium ullum sp. nov. the captures nematodes on adhesive spherical knobs was isolated from soil around Codonopsis lanceolata at Ulleung island, Korea. The spindle-shaped conidia sized $17-44{\mu}m\;(26.5{\mu}m)\;long,\;7-10{\mu}m\;(8.1{\mu}m)$ wide, containing from 1 to 4 cross-walls but most often divided by 2 septa (47%). Resting bodies sized $57{\times}30{\mu}m$. Arthrobotrys amerospora has almost spherical non-septate conidia with a small truncate protuberance at the base and sized $20-27{\mu}m\;(23.3){\mu}m$ long and $11-17{\mu}m\;(14.1){\mu}m$ wide. Conidiophores are somewhat longer $362.8{\mu}m\;(311-418{\mu}m)$ than its original description ($75-250{\mu}m$).

New Constructions of Multi-level ${\mu}TESLA$ with Immediate Authentication (인증지연 없는 멀티-레벨 ${\mu}TESLA$의 새로운 구성)

  • Lim, Chae-Hoon
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.16 no.6
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    • pp.163-167
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    • 2006
  • Multi-level ${\mu}TESLA$ is an efficient extension to ${\mu}TESLA$ to provide an extended lifetime for long-lived sensor networks. This paper presents new constructions of multi-level ${\mu}TESLA$ with immediate authentication of key chain commitments. The proposed constructions are shown to be more efficient and robust than the previous multi-level ${\mu}TESLA$ extension.

A Study on Heavy Metal Concentrations of Oxidized Hair Coloring Products in Korea Market (한국에서 유통 중인 산화형 염모제의 중금속 농도에 관한 연구)

  • Choi, Chae Man;Hong, Mi Sun;Lee, Yun Jung;Kim, Hwa Soon;Kim, Hyun Jung;Kim, Jung Hun;Chae, Young Zoo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.39 no.3
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    • pp.241-249
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    • 2013
  • This study was aimed to provide the fundamental data about oxidized hair color products. For this reason, we collected 125 oxidized hair color products, which were distributed in domestic market from January to October, 2012, and measured the heavy metal concentrations of lead, arsenic, cadmium, chromium, manganese, nickel, copper in the samples. Results were compared by domestic, foreign, henna, type and color. The average metal concentrations were as follows; 0.211 ${\mu}g/g$ for lead, 0.008 ${\mu}g/g$ for cadmium, 0.051 ${\mu}g/g$ for arsenic, 0.954 ${\mu}g/g$ for chromium, 6.250 ${\mu}g/g$ for manganese, 0.591 ${\mu}g/g$ for nickel and 0.544 ${\mu}g/g$ for copper. In case of lead and arsenic, the concentrations were much less than the regulated amount (20 ${\mu}g/g$ and 10 ${\mu}g/g$, respectively) suggested by MFDS (Ministry of Food and Drug Safety). In henna (p < 0.05), the concentrations were significantly higher than those of other domestic and foreign oxidized hair color products as follows; 1.264 ${\mu}g/g$ for lead, 0.267 ${\mu}g/g$ for arsenic, 0.025 ${\mu}g/g$ for cadmium, 4.055 ${\mu}g/g$ for chromium, 72.044 ${\mu}g/g$ for manganese, 3.076 ${\mu}g/g$ for nickel and 4.640 ${\mu}g/g$ for copper. Statistically, it showed that the heavy metal concentrations were quite different for the different types of hair color products. The cream and liquid type products had the highest average concentration in chromium (0.708 ${\mu}g/g$, 0.478 ${\mu}g/g$, respectively). On the other hand, powder type products showed the highest concentration in manganese (60.041 ${\mu}g/g$). In addition, the concentrations of heavy metals and the color of products are not quite correlated. It was shown that average concentrations of lead and chromium were higher for yellow, chromium for red and pink, manganese for brown and black, and nickel for green.