• Title/Summary/Keyword: 유농도

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Trends of Long-Term High Concentrations Ozone in Seoul Metropolitan Area (수도권지역의 장기간 고농도 오존 경향 분석)

  • 마창민;진형아;박철진;한진석;최양일
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2000.04a
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    • pp.57-57
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    • 2000
  • 광화학반웅에 의해 생성되는 오존은 전구물질(precursor)의 발생지역 뿐만아니라 바람에 따라 수송(transport)되어 오염원이 없는 외곽지역에 영향을 주기도 하는데, 지역적 규모(regional scale) 이상의 수평적인 오존 수송을 나타낼 수 있다. 따라서 오존오염은 국지적 현상과 수송에 의한 복합적인 오염현상으로 나타난다. 따라서 지리적으로 인접한 수도권지역은 오존 및 전구물질의 유·출입이 발생하며, 서풍일 경우 인천, 서울, 구리, 춘천까지 시간대별로 고농도의 오존이 관측되기도 한다. (중략)

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포도(Vitis spp.)속 식물의 잎 절편과 callus배양을 통한 영양번식

  • 김진화;이명선
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2003.04a
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    • pp.63-64
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    • 2003
  • 현재 재배되고 있는 포도속 식물 8품종의 잎 절편과 잎 절편에서 얻어진 callus를 이용하여 신초 재생과 체세포배발생 유도 실험을 수행하였다. 생장조절제 종류별 첨가 농도 및 에너지원이 되는 sucrose의 농도별 첨가에 따른 배양 조직의 변화를 살펴보았으며, 활성탄의 첨가 유무가 체세포배발생에 미치는 영향에 관한 실험을 실시하였다. 또한, 잎 절편과 잎 절편에서 얻어진 callus에 $\beta$-glucuronidase (gus) 유전자를 가진 Agrobacterium tumefasciens를 접종하여 포도속의 유전자 전환시 접종 효율을 검정하였다.(중략)

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Effects of enamel matrix derivatives on the proliferation and the release of growth factors of human periodontal ligament cells (법랑기질유도체가 인간 치주인대세포의 증식 및 성장인자 발현에 미치는 영향)

  • Jung, Gyu-Un;Pang, Eun-Kyoung
    • The Journal of Korean Academy of Prosthodontics
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    • v.54 no.3
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    • pp.203-209
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    • 2016
  • Purpose: Stimulating the proliferation and migration of periodontal ligament cells (PDLCs) has become the main goal of periodontal regeneration. To accomplish this goal, regeneration procedures have been developed, but results have not been predictable. Recently, tissue engineering using enamel matrix derivatives (EMDs) and growth factors has been applied to periodontal regeneration; however, the mechanism of EMDs is largely unknown. The aim of this study was to investigate the effects of EMDs on the proliferation and release of growth factors from PDLCs. Materials and methods: Human PDLCs were removed from individually extracted 3rd molars of healthy young adults, and cultured in the media containing EMDs (Emdogain, Biora, Malmo, Sweden) at concentration of 0, 12.5, 25, 50, 100, and $200{\mu}g/mL$ each. Cell proliferation and ALP (alkaline phosphatase) activity were measured. The evaluation of growth factors released by PDLCs was also performed by one-way analysis of variance (ANOVA) and Bonferroni's multiple comparison test. Results: Significantly increased proliferation and ALP activity were observed in PDLCs treated with over $25{\mu}g/mL$ and $50{\mu}g/mL$ EMDs, respectively. Additionally, treatment of PDLCs with $50{\mu}g/mL$ resulted in significantly increased release of vascular endothelial growth factor (VEGF) and transforming growth factor $(TGF)-{\beta}$ after 24 h and 48 h, respectively. Conclusion: EMDs enhance the proliferation and ALP activity of PDLCs, and promote the release of growth factors, including VEGF and $TGF-{\beta}$, from PDLCs. Therefore EMDs could be one of the effective methods for periodontal regeneration.

Antioxidative, Antimutagenic, and Cytotoxic Activities of Ethanol Extracts from Cornus officianalis (산수유(Cornus officianalis) 에탄올 추출물의 항산화, 항돌연변이 활성 및 암세포 성장 억제 효과)

  • Jeon, Yeon-Hee;Kim, Mi-Hyun;Kim, Mee-Ra
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.1
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    • pp.1-7
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    • 2008
  • The antioxidative, antimutagenic and cytotoxic activities of ethanol extract from Cornus officianalis have been studied. The antioxidant activity of the ethanol extract was measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. The inhibition effects on the mutagenicity in Salmonella Typhimurium TA100 were evaluated by Ames test and cancer cell inhibitory effects in Hep3B cell and HeLa cell were tested by MTT assay. Cornus officianalis had an important free radical-scavenging activity towards the DPPH radical. At a concentration of 500 ppm, the DPPH radical-scavenging activity of Cornus officianalis was similar to that of L-ascorbic acid. None of the extracts produced a mutagenic effect on S. Typhimurium TA100. The ethanol extract from Cornus officianalis showed about 77% of inhibition at 500 ppm on the mutagenicity induced by 4-nitroquinoline-1-oxide. The extract from Cornus officianalis showed strong cytotoxicity against Hep3B and HeLa cells, with inhibition of 83 and 78% at a dose of $700{\mu}g$/plate, respectively. Moreover, the ethanol extracts had 34.33 mg H.E/g of polyphenols and 5.67 mg Q.E/g of flavonoids, respectively. Therefore, the present study showed antioxidative, antimutagenic and anticancer potential of the ethanol extract from Cornus officianalis.

Effects of Cattle Slurry Application According to the Slopes on Forage Yield and Nutrient Runoff in Mixed Grassland (경사지에 따른 우분 액비의 시용이 목초의 생산성 및 양분의 유실에 미치는 영향)

  • Jung, Min-Woong;Choi, Ki-Choon;Yoon, Chang;Kim, Won-Ho;Yook, Wan-Bang
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.27 no.1
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    • pp.21-28
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    • 2007
  • This study was conducted to investigate the effects of the degree of slope according to cattle slurry (CS) application on productivity of herbage yield and nutrients runoff in mixed grassland. silage corn and environmental pollution in silage corn cultivation soil. Field study was conducted on the steel-made erosion apparatuses which consisted of various degree of slope, such as 0%, 8.75% and 17.50%, Dry matter yield and N yield of forages decreased as the degree of the slope increased, whereas N contents increased as the degree of slope increased. $NO_3-N$ and $PO_4-P$ concentrations from the surface run-off significantly elevated by increasing the slope during the experimental period (P<0.05). However, $NO_3-N$ and $PO_4-P$ concentrations $PO_4-P$ content from the surface run-off by application of CS maintained a low levels during the experimental period. In conclusion, com productivity and nutrient losses from run-off are significantly affected by heavy rainfall on the sloping land. The results of this study suggest that CS application in the sloping land can be an important source of pollution for surface water if intensity rainfall takes place within a short period.

Development and Characterization of a Hydrolyzed Goat Milk Protein/Chitosan Oligosaccharide Nano-Delivery System (산양유 단백질 분해물/키토올리고당 나노 전달체 제조 및 물리화학적 특성연구)

  • Ha, Ho-Kyung;Kim, Jin Wook;Han, Kyoung-Sik;Yun, Sung Seob;Lee, Mee-Ryung;Lee, Won-Jae
    • Journal of Dairy Science and Biotechnology
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    • v.35 no.3
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    • pp.208-214
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    • 2017
  • The aims of this study were to manufacture a hydrolyzed goat milk protein (HGMP)/chitosan ologisaccharide (CSO) nano-delivery system (NDS) and to investigate the effects of production variables, such as sodium tripolyphosphate (TPP), HGMP, and CSO concentration levels, on the formation and physicochemical properties of the NDS. An HGMP/CSO NDS was produced using the ionic gelation method at pH 5.5. Transmission electron microscopy and a particle size analyzer were used to determine the morphological and physicochemical properties of NDSs, respectively. The size of the HGMP/CSO NDS decreased from 225 to 138 nm as HGMP and CSO concentration levels decreased. The NDS had a positive surface charge, with a zeta-potential value of +23 mV. The encapsulation efficiency (EE) of docosahexaenoic acid was enhanced as the HGMP concentration level increased. Additionally, increasing the concentration level of CSO resulted in an increase in the EE of resveratrol. The HGMP/CSO NDS exhibited good physical stability during freeze-drying. Thus, our findings showed that the HGMP/CSO NDS was successfully manufactured and that HGMP and CSO concentration levels were key factors affecting the physicochemical properties of the NDS.

Physicochemical Properties and Distribution of Heavy Metals in Stream Sediments of the Daejeon Area (대전지역 주요하천 하상퇴적물의 물리화학적 특성 및 중금속 분포)

  • Jeong, Chan-Ho;Lee, Sang-Gu
    • Journal of the Mineralogical Society of Korea
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    • v.19 no.4 s.50
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    • pp.259-264
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    • 2006
  • This work carried out to analyze the physicochemical properties and investigate the assessment of heavy metal contamination of stream sediments of the Yudeung and the Gab streams in the Daejeon area. The pH of stream sediments of the Yudeung stream shows the range of weak acid and weak alkaline. Most of stream sediments contain about 80% sand grain and have low water and cation retention capacity. Hence the stream sediments are not suitable fur various plans to grow up. The analysis of heavy metals in the stream sediments shows that the concentration of Pb, Cr and Cd increases from upstream to down stream. It is likely that the trend has a relationship with the water. Contamination of stream water. The authors recommend that clay materials be replenished in the stream sediments to increase the self-purification capacity and to make the suitable condition for growing up of various plants, and that water quality of the stream which can Influence into the contamination of stream sediments be monitored.

Biological Treatment on Wastewater of Soluble Metal Working Fluids (수용성 금속가공유 폐액의 생물학적 처리)

  • 차미선;한창민;박근태;조순자;손홍주;이상준
    • Journal of Life Science
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    • v.13 no.6
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    • pp.917-923
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    • 2003
  • The present investigation was conducted to determine the chemical oxygen demand (COD) removal efficiency by Pseudomonas aeruginosa EMS1. The COD removal efficiency in the medium containing 1% metal working fluid (MWF) was 12% after cultivation of 4 days. The composition of optimum medium for the COD removal efficiency of 1% MWF by P. aeruginosa EMS1 were NH$_4$Cl 0.3%,$ K_2HPO_4\; 0.05%,\; KH_2PO_4\; 0.04%,\; MgSO_4.7H_2O\; 0.05%,\; CaCl_2.2H_2O 0.03%$ and $FeSO_4.7H_2O$ 0.04% at initial pH 7.0 and $30^{\circ}C$. Under this condition, the highest the COD removal efficiency was observed after 4 days.

Effect of Methodologies for Laser-Induced Plasma Creation on Hydrogen Sensing (레이저 유도 플라스마 생성 방법이 수소 검출에 미치는 영향)

  • Jang, Jung-Ik;Kim, Ki-Bum
    • Transactions of the KSME C: Technology and Education
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    • v.3 no.4
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    • pp.291-297
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    • 2015
  • As promising future energy source, hydrogen has been drawing much attention; however, it is easily leaked from the small gap in any storage container due to its find molecule size. In this study, Laser induced breakdown spectroscopy(LIBS) was used for hydrogen leak detection, and feasibility of the scheme was evaluated based on different way for plasma generation. Laser power of 295 mW was required for generating plasma on metal surface to measure hydrogen atomic emission while approximately 2.5 times higher laser power was needed for plasma formation directly in the hydrogen gas stream. It was shown that peak to base ratio increased linearly with increasing the concentration of hydrogen. It can be concluded that LIBS is a viable technique for hydrogen sensing when the concentration of hydrogen is less than 5%.

The In-Situ Ozone Oxidative Remediation Potential of Diesel Fuel-contaminated Soil (디젤오염토양에 대한 지중 오존산화처리 적용 가능성)

  • 유도윤;신응배;배우근
    • Journal of Korea Soil Environment Society
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    • v.4 no.3
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    • pp.3-15
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    • 1999
  • This paper includes the basic experimental results performed for developing an innovative and technologically feasible process wherein gaseous ozone, a powerful oxidant. is injected directly into vadose zone by which in-situ chemical degradation of semi- or, non-volatile petroleum product such as diesel fuel is derived. As ozone gas injected continuously(50mL/min, 119.0$\pm$6.1mg/L) into soil packed columns artificially contaminated with diesel fuel(initial concentration 1,485mg-DRO/kg/soil), the removal rates at the inlet and outlet point of 14hrs-operated column are 87.9% and 100.0%, respectively. On the other hand, soil vapor extraction system showed less than 30% of removal rates of residual diesel both at the inlet and outlet samples under the same experimental conditions which confirms the limited treatability of SVE in diesel contaminated soil.

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