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Mineralogy and Genetic Environments of the Seongdo Pb-Zn deposit, Goesan (괴산 성도 연-아연 광상의 산출광물과 생성환경)

  • Ahn, Seongyeol;Shin, Dongbok
    • Economic and Environmental Geology
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    • v.50 no.5
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    • pp.325-340
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    • 2017
  • The Seongdo Pb-Zn deposit, located in the northwestern part of the Ogcheon Metamorphic Belt, consists of skarn ore replacing limestone within the Hwajeonri Formation of Ogcheon Group and hydrothermal vein ore filling the fracture of host rock. Skarn minerals comprise mostly hedenbergitic pyroxene, garnet displaying oscillatory zonal texture composed of grossular and andradite, and a small amount of wollastonite, tremolite, and epidote, indicating reducing condition of formation. Ore minerals of skarn ore include sphalerite and galena with a small amount of pyrite, pyrrhotite, and chalcopyrite. In hydrothermal vein ore, arsenopyrite, sphalerite, chalcopyrite, and pyrite occur with a small amount of galena, native Bi, and stannite. Chemical compositions of sphalerite vary from 17.4 mole% FeS in average for dark grey sphalerite, 3.6 mole% for reddish brown sphalerite in skarn ore, and to 10.3 mole% FeS in hydrothermal vein ore. In comparison with representative metallic deposits in South Korea on the FeS-MnS-CdS diagram, skarn and hydrothermal vein ore plot close to the field of Pb-Zn deposits and Au-Ag deposits, respectively. Arsenic contents of arsenopyrite in hydrothermal vein ore decrease from 31.93~33.00 at.% in early stage to 29.58~30.21 at.% in middle stage, and their corresponding mineralizing temperature and sulfur fugacity are $441{\sim}490^{\circ}C$, $10^{-6}{\sim}10^{-4.5}atm$. and $330{\sim}364^{\circ}C$, <$10^{-8}atm$. respectively. Phase equilibrium temperatures calculated from Fe and Zn contents for coexisting sphalerite and stannite in hydrothermal vein are $236{\sim}254^{\circ}C$. Sulfur isotope compositions are 5.4~7.2‰ for skarn ore and 5.4~8.4‰ for hydrothermal vein ore, being similar or slightly higher to magmatic sulfur, suggesting that ore sulfur was mostly of magmatic origin with partial derivation from host rocks. However, much higher sulfur isotope equilibrium temperatures of $549^{\circ}C$$487^{\circ}C$, respectively for skarn ore and hydrothermal ore, than those estimated from phase equilibria imply that isotopic equilibrium has not been fully established.

Studies on Utilization Survey and Forage Quality of Phragmites communis and Miscanthus sinensis as Native Grasses in Paju and Ansan District, 2010 (2010 파주, 안산지역 갈대, 억새 등 야초류의 이용실태와 사료가치 평가)

  • Seo, Sung;Kim, Won-Ho;Jung, Min-Woong;Park, Hyung-Soo;Shim, Jae-Jin;Park, Jin-Gil;Sung, Ha-Guyn;Kim, Jong-Duk;Lee, Joung-Kyong
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.31 no.2
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    • pp.151-158
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    • 2011
  • This study was carried out in 2010 to investigate the utilization and nutritive value of native grasses, such as Phragmites communis and Miscanthus sinensis which might reduce the cost of feeding domestic cattle. The regions within the Civilian Control Line in Paju and Sihwa region in Ansan were surveyed. In Paju, the yearly silage production was 900 MT harvested from 90 ha (10 MT/ha). About 30~50% of these were sold out at the marketing price of 52,000~55,000 Won per roll (130~137.5 Won/kg). Regrown Miscanthus sinensis of 70 cm in length contained 9.6% of crude protein (CP), 82.4 of relative feed value (RFV), and 67.7% of in vitro dry matter digestibility (IVDMD). Regrown Phragmites communis of 70 cm in length contained 13.8% of CP, 84.3 of RFV, and 67.9% of IVDMD. As harvesting was delayed, the quality was decreased dramatically. In Ansan region, Phragmites communis plantation covers 100 ha. The silage production was 550 MT from the area of 50 ha (11 MT/ha) in 2009. And the marketing price was 50,000 Won per roll. But in 2010 only a small amount of grasses could have been baled due to frequent and much rainfall from spring to summer season. However, the good forage quality was observed from regrown Phragmites communis of 80 cm in length, 12.9% CP, 99.8 RFV and 66.6% IVDMD, while that of late matured grasses was very low, 2.2% CP, 52.9 RFV and 36.4% IVDMD, greatly lower than forage quality of rice straw. The quality of grasses at bloom stage of 150 cm in length was similar to that of rice straw, showing 4.5% CP, 59.9 RFV and 42.2% IVDMD. In conclusion, the overall quality of most native grasses in this survey were very poor. Therefore, we recommend that Phragmites communis and Miscanthus sinensis should be harvested during June or July to obtain better forage quality which is richer in forage values than rice straw. Production of high quality forage crops was also desirable for self sufficiency of forage.

Physiological Activity of Sarcodon aspratus Extracts (능이버섯(Sarcodon aspratus) 추출물의 생리활성)

  • 송재환;이현숙;황진국;한정환;노정근;금동혁;박기문
    • Food Science of Animal Resources
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    • v.23 no.2
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    • pp.172-179
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    • 2003
  • This study was carried out to find the preventive medical and therapeutic effects of Sarcodon asparatus on adult disease by employing several biological and biochemical assays. Nitrate scavenging ability(NSA) of Sarcodan asparatus extracts was displayed up to 99.9% at pH 1.2 in a dose-dependent manner. They also had 90.4% electron donating ability(EDA) at the concentration of 0.1 mg/mL. Extracts of Sarcodon asparatus were also able to function as a powerful antioxidant at all concentrations(0.01∼l.0 mg/mL). Furthermore, we observed that 1 mg/mL concentration of the extracts was more powerful than BHT, With respect to fibrolytic activity, Sarcodon asparatus showed 1,843.8 unit/g, which was higher than streptokinase(1,189 unit/g). The inhibitory effects of the extracts on angiotensin converting enzyme, measured by the normal and pretreatment methods, were 53 and 58%, respectively. We also performed cytotoxicity effect of Sarcodon asparatus extracts on a various cancer cell lines. The growth inhibitory effects of the extracts(5.0 mg/mL) on A549, HeLa, AGS, and SK-Hep-1 cells were 78.9, 55.3, 69.0, and 42.5 %, respectively. Interestingly, Sarcodon asparatusextracts induced mutation on Salmonella typhimurium TA98 and TA100 when Ames test was done.

Antibacterial Activities of Bamboo Sap Against Salmonella Typhimurium and Inhibitory Effects in a Model Food System (죽력의 Salmonella typhimurium 등에 대한 항세균 활성과 Model Food System에서의 생육억제 효과)

  • Chung, Hee-Jong;Ko, Bong-Guk
    • Journal of the Korean Society of Food Culture
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    • v.20 no.6
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    • pp.709-714
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    • 2005
  • Antibacterial activities of the freeze-dried bamboo sap dissolved into the water or 50% ethanol were determined and antimicrobial activity of bamboo sap dissolved into distilled water was most strong with 15 mm of the diameter of inhibiting clear zone against Listeria monocytogenes ATCC 19114 among gram positive bacteria tested, but it did not inhibit Bacillus subtilis ATCC 6633 at all, and the sap was most greatly inhibited the growth of Shigella dysenteriae ATCC 9361 among gram negative bacteria with 15 mm of the diameter of inhibiting clear zone. Bamboo sap dissolved into 50% ethanol most strongly inhibited the growth of L. monocytogenes ATCC 19114 and it also inhibited the growth of B. subtilis ATCC 6633 which did not show any with the sap dissolved into distilled water. The sap dissolved into 50% ethanol was most greatly inhibited the growth of S. dysenteriae ATCC 9361 among gram negative bacteria with 23 mm of the diameter of inhibiting clear zone, and it inhibited Vibrio parahaemolyticus WSDH 22, Vibrio vulnilicus ATCC 29307 and Escherichia coli O157 WSDH 54 with 16 mm of the diameter of inhibiting clear zone. However, Both of the saps dissolved in distilled water and 50% ethanol did not showed any inhibition against the lactic acid bacteria of Lactobacillus plantarum KCTC and Lactobacillus brevis KCTC. Most of the tested bacteria were more sensitive to the sap dissolved in 50% ethanol than the sap dissolved in distilled water. The lowest minimum inhibitory concentration of the bamboo sap dissolved into 50% ethanol was 0.6 mg eq./disc with L. monocytogenes ATCC 19114, but that of the sap dissolved into distilled water was 0.8 mg eq./disc with Staphylococcus epidermides ATCC 12228, S. dysenteriae ATCC 9361, L. monocytogenes ATCC 19114, Salmonella typhimurium WSU 2380 and V. parahaemolyticus WSDH 22. In a model food system of the sterilized chocolate milk, antibacterial activities of the sap dissolved into 50% ethanol were relatively stronger than those of the sap dissolved into distilled water and the activities against the bacteria tested were very similar each other. These result suggested the bamboo sap can be used as a natural food preservative.

Axial wall thickness of zirconia abutment in anterior region (전치부 지르코니아 지대주의 축벽 두께)

  • Moon, Seung-Jin;Heo, Yu-Ri;Lee, Gyeong-Je;Kim, Hee-Jung
    • The Journal of Korean Academy of Prosthodontics
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    • v.53 no.4
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    • pp.345-351
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    • 2015
  • Purpose: The purpose of this study was to evaluate the proper axial thickness of zirconia abutment applied to implant in the anterior region. Materials and methods: Zirconia abutments were prepared at different axial wall thickness by processing pre-sintered zirconia blocks via CAD/CAM to obtain equal specimens. The abutments were each produced with a thickness of 0.5 mm (Group 1), 0.8 mm (Group 2), 1.2 mm (Group 3), or 1.5 mm (Group 4). The implant used in this study was a external connection type one (US, Osstem, Pussan, Korea) product and the zirconia abutment was prepared via replication of a cemented abutment. The crowns were prepared via CAM/CAM with a thickness of 1.5 mm and were cemented to the abutments using $RelyX^{TM}$ UniCem cement. A universal testing machine was used to apply load at 30 degrees and measure fracture strength of the zirconia abutment. Results: Fracture strength of the abutments for Group 1, Group 2, Group 3, and Group 4 were $236.00{\pm}67.55N$, $599.00{\pm}15.80N$, $588.20{\pm}33.18N$, and $97.83{\pm}98.13N$, respectively. Group 1 showed a significantly lower value, as compared to the other groups (independent Mann-Whitney U-test. P<.05). No significant differences were detected among Group 2, Group 3, and Group 4 (independent Mann-Whitney U-test. P>.05). Conclusion: Zirconia abutment requires optimal thickness for fracture resistance. Within the limitation of this study, > 0.8 mm thickness is recommended for zirconia abutment in anterior implants.

Antimutagenic and Cytotoxic Effects of Acer ginnala Max. Bark Extracts (신나무 껍질 추출물의 항돌연변이원성 및 세포독성 효과)

  • Oh Heung-Seok;Cui Cheng-Bi;Choi Hyung-Taek;Kim Soo-Hyun;Jeon Mi-Sun;Ham Seung-Shi
    • Food Science and Preservation
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    • v.11 no.4
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    • pp.550-556
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    • 2004
  • In the present study, we investigated the antimutagenic and cytotoxic effects of Acer ginnala Max. bark extract on S. typhimurium TA98, TA100 and cancer cell lines with Ames test and SRB assay, respectively. They were extracted with methanol and then fractionated using hexane, chloroform, ethyl acetate, butanol, and water to obtain the fractions. The inhibition rate of methanol ($200\;{\mu}g/plate$) of Acer ginnala Max. bark extract in the Salmonella typhimurium TA100 strain showed $83.3\%$ against the mutagenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). In addition, the suppression of methanol extract with same concentration of in the Salmonella typhimurium TA98 and TA100 strains showed $80.3\%\;and\;92.7\%$ inhibition against 3-amino-1,4-dimethyl-5H-pyrido-(4,3-b)indol (Trp-P-1), respectively. The cytotoxicity effects of Acer ginnala Max. bark extract against the cell lines with human lung carcinoma (A549), human gastric carcinoma (AGS), human hepatocellular carcinoma (Hep3B) and human breast adenocarcinoma (MCF-7) were inhibited with the increase of the extract concentration. The treatment of 1.0 mg/mL Acer ginnala Max. bark methanol extract of methanol showed strong cytotoxicities of $77.3\%,\;90.4\%,\;88.9\%,\;and\;83.7\%$ against A549, AGS, Hep3B and MCF-7, respectively.

Screening of immune enhancing activities in medicinal herbs, Compositae (국화과 약용 식물의 면역증진활성 검색)

  • Lee, Mi-Kyoung;Moon, Hyoung-Chol;Lee, Jin-Ha;Kim, Jong-Dai;Yu, Chang-Yeon;Lee, Hyeon-Yong
    • Korean Journal of Medicinal Crop Science
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    • v.10 no.1
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    • pp.51-57
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    • 2002
  • The biological activities of immune modulating activities of the extracts from Echinacea purpurea, Chrysanthmum indicum L. and Circium japonicum var. ussuriense KITAMURA were compared. About 70% of the growth of human hepatocarcinoma and 80% of human gastric cancer cell was inhibited in adding 0.5mg/ml of the ethanol extracts of Echinacea purpurea, Chrysanthmum indicum L. and Circium japonicum var. ussuriense KITAMURA, respectively. The growth of human breast cancer cells was also inhibited in adding 0.5mg/ml of the extracts as well as 60% of the human cancer cells. It was proved that the growth of human normal lung cell, scored as 15% for the extracts. Overall selectivity of the extracts on several human cancer cell line was over 3, which is higher than those from the conventional herbs. The growth of both human immune B and T cells was enhanced up to 1.4 to 2.0 times by adding the extracts, compared to the controls. The secretion of tumor necrosis $factor-alpha(TNF-{\alpha})$ from T cell was also increased up to 94 pg/ml in adding the Echinacea purpurea ethanol extract (0.5mg/ml). Circium japonicum var. ethanol extract also increased up to about 96 pg/ml of interleukin-6(IL-6) from B cell.

EXPRESSION OF BMP4, BMP6 FOLLOWING SINUS ELEVATION WITH DBBP IN RABBIT (가토 상악동 점막 거상 후 DBBP를 이식재로 사용시 BMP4, BMP6의 발현)

  • Lee, Hyun-Suk;Heo, Hyun-A;Pyo, Sung-Woon;Lee, Won
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.29 no.6
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    • pp.467-473
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    • 2007
  • The most important factor for successful implantation is osseointegration between the implant and bone. The expression of bone morphogenetic proteins (BMPs) inducing bone formation would differ after maxillary sinus elevation. And within the same graft material. the expression of BMPs would change with time after graft. The aim of this study was to compare the relative expressions of BMP4 and BMP6 using real-time RT-PCR when maxillary sinus elevation was performed using deproteinated bovine bone powder (DBBP) as the graft material or absorbable gelatin sponge (AGS) as the filler without any graft material. Fifteen rabbits, each weighing between 3.0 to 3.5 Kg, were divided randomly into 5 groups of 3 animals each based on their time of sacrifice 0, 3, 5, 7 and 9 days). After exposure of the maxillary sinus bilaterally, bone graft was performed in the right maxillary sinus using DBBP ($BBP^{(R)}$ Oct Inc., Cheonan, Korea) and only AGS ($Gelfoam^{(R)}$ Pharmacia & Upjohn Company, Kalamazoo, MI, U.S.A) was placed into the left without any graft material. Each group of rabbits was sacrificed at 1, 3, 5, 7, or 9 days after operation and all specimens were harvested. And the following results were obtained using real-time RT-PCR from isolated total RNA of the samples. 1. The expression of BMP4 increased at postoperative 1 and 3 days in both DBBP group and AGS group. In AGS group. it decreased at postoperative 5 days. increased again at postoperative 7 days, and decreased at postoperative 9 days. In DBBP group, it increased until postoperative 7 days and decreased at postoperative 9 days. Although the expression of BMP4 was higher in DBBP group compared with AGS group, it was not statistically significant (p>0.05). 2. The expression of BMP6 increased at postoperative 1 and 3 days in both DBBP group and AGS group. In AGS group, it decreased at postoperative 5 days, increased again at postoperative 7 days, and decreased at postoperative 9 days. In DBBP group, it increased until postoperative 7 days and decreased at postoperative 9 days. Although the expression of BMP6 was higher in AGS group compared with DBBP group, it was not statistically significant (p>0.05). 3. There was no statistically significant difference in BMP expression in both groups during same period of time. It' s probably because DBBP and AGS both functioned as a space retainer so that the BMP expression in blood clot seemed to be similar. 4. Thus, DBBP would not offer many benefits for early bone regeneration compared with AGS. The expression of BMP in early bone formation seems to be more influenced by physical carrier rather than the graft type.

Current Research Trend of Postharvest Technology for Chrysanthemum (국화 수확 후 관리기술의 최근 연구 동향)

  • Kim, Su-Jeong;Lee, Seung-Koo;Kim, Ki-Sun
    • Korean Journal of Plant Resources
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    • v.25 no.1
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    • pp.156-168
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    • 2012
  • Chrysanthemum is a cut flower species that normally lasts for 1 to 2 weeks, in some cases 3-4 weeks. This has been attributed to low ethylene production during senescence. Reduction in cut flower quality has been attributed to the formation of air embolisms that partially or completely blocks the water transport from the vase solution to the rest of the cut flower stem, increasing hydraulic resistance which may cause severe water stress, yellowing, wilting of leaf, and chlorophyll degradation. Standard type chrysanthemum can be harvested when buds were still tightly closed and then fully opened with the simple bud-opening solution. Standard type chrysanthemum can also be harvested when the minimum size of the inflorescence is about 5-6 cm bud which opened into the first flower full-sized flower. While spray varieties can be harvested when 2-4 most mature flowers have opened (40% opening). Cut flowers are sorted by stem length, weight, condition, and so on. Standard chrysanthemum is 80 cm length for standard type and 70cm for spray type. Pre-treatment with a STS, plant regulator such as GA, BA, 1-MCP, chrysal, germicide, and sucrose, significantly improved the vase life and quality of cut flowers. It is well established that vase solutions containing sugar can improve the vase life of cut chrysanthemum. Chrysanthemum is normally packed in standard horizontal fiberboard boxes. Chrysanthemum should normally be stored at $5{\sim}7^{\circ}C$. Precooling resulted in reduction in respiration, decomposition, and transpiration activities as well as decoloration retardation. There was significant difference between "wet" storage in 3 weeks and "dry" storage in 2 weeks. In separate pulsing solution trials, various germicides were tested, as well as PGRs to maintain the green color of leaves and turgidity. Prolonging vase life was attained with the application of optimal solution such as HQS, $AgNO_3$, GA, BA and sucrose. This also retarded senescence in leaves of cut flower stems. Fresh cut chrysanthemum can be transported using a refrigerated van with $5{\sim}7^{\circ}C$. Increasing consumption and usage of cut chrysanthemum of various cultivars would require efficient transport system, and effective information exchange among producer, wholesaler, and consumer.

Studies on Fungal Contamination and Mycotoxins of Rice Straw Round Bale Silage (사료용 볏짚 곤포사일리지의 곰팡이 및 Mycotoxin 오염 연구)

  • Sung, Ha-Guyn;Lee, Joung-Kyong;Seo, Sung
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.31 no.4
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    • pp.451-462
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    • 2011
  • The purpose of this study was to investigate fungi and mycotoxin contamination of the rice straw bale silage in Korean. It was tested the 33 samples of rice straw round bale silage with various condition which fed cattle in the farm. The level of fungal contamination was $2.1{\times}10^6\;cfu\;g^{-1}$ in the average and $9.2{\times}10^8\;cfu\;g^{-1}$ in the maximum. The fungal contamination was detected in the all of normal samples which good condition of rice straw bale silage. When the fungi was isolate and identify, it was found 28 species and mycotoxin producing fungi were 8 species as following as Aspergillus flavus, Aspergillus fumigatus, Fusarium culmorum, Fusarium verticillioides, Penicillium carneum, Penicillium paneum, Penicillium roqueforti, Penicillium viridicatum. Specially, Penicillium paneum was found 42% of samples and Aspergillus sp. (A. flavus, A. fumigatus) are 21% of samples. In case of mycotoxin contamination, the 42% of samples are detected more than one kind of mycotoxin. Some samples are contaminated three kinds of mycotoxin. This study was not found aflatoxin ($B_1$, $B_2$, $G_1$, $G_2$) and fumonisin ($B_1$, $B_2$), but were detected the contamination of ochratoxin A (1.0~5.8 ug/kg), deoxynivalenol (DON, 156.0~776.7 ug/kg) and zearalenone (ZON, 38.0~750.0 ug/kg). Therefore, the above results show that rice straw round bale silage expose on hazard factors as mycotoxigenic fungi and mycotoxin contamination, and than need more research about mycotoxin in animal feed to protect animal and human healthy.