• Title/Summary/Keyword: 원접촉

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Chemical Mass Balance of Materials in the Keum River Estuary: 1. Seasonal Distribution of Nutrients (금강하구의 물질수지: 1. 영양염의 계절적 분포)

  • Yang, Jae-Sam;Jeong, Ju-Young;Heo, Jin-Young;Lee, Sang-Ho;Choi, Jin-Yong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.4 no.1
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    • pp.71-79
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    • 1999
  • As part of an on-going project investigating flux of materials in the Keum River Estuary, we have monitored seasonal variations of nutrients, suspended particulate matter (SPM), chlorophyll, and salinity since 1997. Meteorological data and freshwater discharge from the Keum River Dike were also used, Our goal was to answers for (1) what is the main factor for the seasonal fluctuation of nutrients in the Keum River Estuary? and (2) are there any differences in nutrient distributions before and after the Keum River Dike construction? Nitrate concentrations in the Keum River water were kept constant through the year. Whereas other nutrients varied with evident seasonality: high phosphate and ammonium concentrations during the dry season and enhanced silicate contents during the rainy season. SPM was found similar trend with silicate. During the rainy season, the freshwater discharged from the Keum River Dike seemed to dilute the phosphate and ammonium, but to elevate SPM concentration in the Keum Estuary. In addition, the corresponding variations of SPM contents in the estuarine water affected the seasonal fluctuations of nutrients in the Estuary. The most important source of the nutrients in the estuarine water is the fluvial water. Therefore, the distribution patterns of nutrients in the Estuary are conservative against salinity. Nitrate, nitrite and silicate are conservative through the year. The distribution of phosphate and ammonium on the other hand, display two distinct seasonal patterns: conservative behavior during the dry season and some additive processes during the rainy days. Mass destruction of freshwater phytoplankton in the riverine water is believed to be a major additive source of phosphate in the upper Estuary. Desorption processes of phosphate and ammonium from SPM and organic matter probably contribute extra source of addition. Benthic flux of phosphate and ammonium from the sediment into overlying estuarine water can not be excluded as another source. After the Keum River Dike construction, the concentrations of SPM decreased markedly and their role in controlling of nutrient concentrations in the Estuary has probably diminished. We found low salinity (5~15 psu) within 1 km away from the Dike during the dry season. Therefore we conclude that the only limited area of inner estuary function as a real estuary and the rest part rather be like a bay during the dry season. However, during the rainy season, the entire estuary as the mixing place of freshwater and seawater. Compared to the environmental conditions of the Estuary before the Dike construction, tidal current velocity and turbidity are decreased, but nutrient concentrations and chance of massive algal bloom such as red tide outbreak markedly increased.

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Acid Drainage and Damage Reduction Strategy in Construction Site: An Introduction (건설현장 산성배수의 발생현황 및 피해저감대책)

  • Kim, Jae-Gon
    • Economic and Environmental Geology
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    • v.40 no.5
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    • pp.651-660
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    • 2007
  • Acid drainage has been recognized as an environmental concern in abandoned mine sites for long time. Recently, the environmental and structural damage by acid drainage is a current issue in construction sites in Korea. Here, the author introduces the type of damages by acid drainage in construction sites and emphasizes the importance of geoscience discipline in solving the problem. Metasedimentary rock of Okcheon group, coal bed of Pyeongan group, Mesozoic volcanic rock. and Tertiary sedimentary and volcanic rocks are the major rock types with a high potential for acid drainage upon excavation in Korea. The acid drainage causes the acidification and heavy metal contamination of soil, surface water and groundwater, the reduction of slope stability, the corrosion of slope structure, the damage on plant growth, the damage on landscape and the deterioration of concrete and asphalt pavement. The countermeasure for acid drainage is the treatment of acid drainage and the prevention of acid drainage. The treatment of acid drainage can be classified into active and passive treatments depending on the degree of natural process in the treatment. Removal of oxidants, reduction of oxidant generation and encapsulation of sulfide are employed for the prevention of acid drainage generation.

Microbial Contamination Levels in the Raw Materials of Home Meal Replacement Shabu-Shabu Meal Kit Distributed in Markets (가정간편식(Home Meal Replacement, HMR) 샤브샤브 밀키트의 원료별 미생물 오염도 분석)

  • Jeon, Eun Bi;Kim, Ji Yoon;Choi, Man-Seok;Choi, Seungho;Bang, Hyeon-Jo;Park, Shin Young
    • Journal of Food Hygiene and Safety
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    • v.35 no.4
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    • pp.375-381
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    • 2020
  • This study assessed the contamination levels of total aerobic bacteria, fungi, coliforms, Escherichia coli, Bacillus cereus, and Staphylococcus aureus and qualitative analysis of Salmonella spp. and Listeria monocytogens in six raw materials (beef, bean sprout, Chinese cabbage, king oyster mushroom, Korean cabbage, and sweet pumpkin) of home meal replacement (HMR) Shabu-Shabu meal kit distributed in markets. The total aerobic bacteria, fungi, and coliforms were detected as 3.98-6.50, 2.78-3.52, and 2.02-3.28 log CFU/g, respectively. Especially, beef was highly contaminated with total aerobic bacteria (6.50 log CFU/g) and coliforms (3.28 log CFU/g). Over 5 log CFU/g of total aerobic bacteria were also detected in bean sprout, Chinese cabbage, and sweet pumpkin. Less than < 2 log CFU/g of coliforms were detected in all vegetables. E. coli was not detected in any of the six samples (ND: < 1 log CFU/g). S. aureus was detected as 1.33-1.71 log CFU/g in most samples but it was not detected in beef and Korean cabbage. B. cereus was assessed as 1.15-2.01 log CFU/g in most samples but it was not detected in Korean cabbage. L. monocytogenes was qualitatively detected as 25-50% in most samples except for king oyster mushroom. Salmonella spp. were not qualitatively detected in any of the six samples. The microbial contamination levels determined in the current study may be potentially used as the basic data to execute microbial risk assessments of HMR foods such as Shabu-Shabu meal kit.

The Optimal Activation State of Dendritic Cells for the Induction of Antitumor Immunity (항종양 면역반응 유도를 위한 수지상세포의 최적 활성화 조건)

  • Nam, Byung-Hyouk;Jo, Wool-Soon;Lee, Ki-Won;Oh, Su-Jung;Kang, Eun-Young;Choi, Yu-Jin;Do, Eun-Ju;Hong, Sook-Hee;Lim, Young-Jin;Kim, Ki-Uk;Jeong, Min-Ho
    • Journal of Life Science
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    • v.16 no.6
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    • pp.904-910
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    • 2006
  • Dendritic cells (DCs) are the only antigen presenting cells (APCs) capable of initiating immune responses, which is crucial for priming the specific cytotoxic T lymphocyte (CTL) response and tumor immunity. Upon activation by DCs, CD4+ helper T cells can cross-prime CD8+ CTLs via IL-12. However, recently activated DCs were described to prime in vitro strong T helper cell type 1 $(Th_1)$ responses, whereas at later time points, they preferentially prime $Th_2$ cells. Therfore, we examined in this study the optimum kinetic state of DCs activation impacted on in vivo priming of tumor-specific CTLs by using ovalbumin (OVA) tumor antigen model. Bone-marrow-derived DCs showed an appropriate expression of surface MHC and costimulatory molecules after 6 or 7-day differentiation. The 6-day differentiated DCs pulsed with OVA antigen for 8 h (8-h DC) and followed by restimulation with LPS for 24 h maintained high interleukin (IL)-12 production potential, accompanying the decreased level in their secretion by delayed re-exposure time to LPS. Furthermore, immunization with 8-h DC induced higher intracellular $interferon(IFN)-{\gamma}+/CD8+T$ cells and elicited more powerful cytotoxicity of splenocytes to EG7 cells, a clone of EL4 cells transfected with an OVA cDNA, than immunization with 24-h DC. In the animal study for the evaluation of therapeutic or protective antitumor immunity, immunization with 8-h DC induced an effective antitumor immunity against tumor of EG7 cells and completely protected mice from tumor formation and prolonged survival, respectively. The most commonly used and clinically applied DC-based vaccine is based on in vitro antigen loading for 24 h. However, our data indicated that antigen stimulation over 8 h decreased antitumor immunity with functional exhaustion of DCs, and that the 8-h DC would be an optimum activation state impacted on in vivo priming of tumor-specific CTLs and subsequently lead to induction of strong antitumor immunity.

A Conceptual Framework for One Source Multi Use Strategy of Culture Content (브랜드 아이덴티티 기반 문화콘텐츠 OSMU 전략 연구)

  • Kim, Young-Jae
    • Cartoon and Animation Studies
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    • s.28
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    • pp.155-180
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    • 2012
  • This article is to propose a conceptual framework for the One Source Multi Use (OSMU) strategic model of culture content. In this study, OSMU is defined as a series of marketing activities to increase the value created by culture content. The framework of brand equity strategy is applied to develop the strategic model of OSMU, as both share the same goal - maximization of long term value created by brand or culture content. This article suggests the brand identity-based OSMU strategic model, in which the brand identity of culture content guides, integrates, and coordinates every decision-making of OSMU activities. For the maximization of brand equity value of culture content, the copyright holder of original content should decide the content's brand identity, which should provide the criteria of all decision makings regarding window strategy, adaptation of content to other genre, and merchandising. This brand identity-based OSMU strategic model can not only contribute to the sales of OSMU content, but also the creation of high equity culture content in the long run. Also, the model allows monitoring and evaluation of content's brand equity, which can be used for the strategic adjustment for the sake of long term value of the content. This study is differentiated from previous study on OSMU and expected to invigorate the further discussion on OSMU in several points. First, it broadens the scope of OSMU discussion as it views OSMU as a series of process including feedback. Second, this study points out the need for integration and coordination of various OSMU activities. Third, the strategic focus is laid on the value maximization of the original content, not 'multi used' content. Fourth, the suggested model emphasize the strategic role of copyright holder who takes the charge of the content brand management. Fifth, the model requires discussion on the components of marketing communication in addition to the content itself, which means the model includes the prospects, not only the content consumers, as the major future source for value creation.

Dynamics of Barrel-Shaped Young Supernova Remnants (항아리 형태 젊은 초신성 잔해의 동력학)

  • Choe, Seung-Urn;Jung, Hyun-Chul
    • Journal of the Korean earth science society
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    • v.23 no.4
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    • pp.357-368
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    • 2002
  • In this study we have tried to explain the barrel-shaped morphology for young supernova remnants considering the dynamical effects of the ejecta. We consider the magnetic field amplification resulting from the Rayleigh-Taylor instability near the contact discontinuity. We can generate the synthetic radio image assuming the cosmic-ray pressure and calculate the azimuthal intensity ratio (A) to enable a quantitative comparison with observations. The postshock magnetic field are amplified by shearing, stretching, and compressing at the R-T finger boundary. The evolution of the instability strongly depends on the deceleration of the ejecta and the evolutionary stage of the remnant. the strength of the magnetic field increases in the initial phase and decreases after the reverse shock passes the constant density region of the ejecta. However, some memory of the earlier phases of amplification is retained in the interior even when the outer regions turn into a blast wave. The ratio of the averaged magnetic field strength at the equator to the one at the pole in the turbulent region can amount to 7.5 at the peak. The magnetic field amplification can make the large azimuthal intensity ratio (A=15). The magnitude of the amplification is sensitive to numerical resolution. This mens the magnetic field amplification can explain the barrel-shaped morphology of young supernova remnant without the dependence of the efficiency of the cosmic-ray acceleration on the magnetic field configuration. In order for this mechanism to be effective, the surrounding magnetic field must be well-ordered. The small number of barrel-shaped remnants may indicate that this condition rarely occurs.

High Resolution Gravity Mapping and Its Interpretation from both Shipborne and Satellite Gravity Data in the Ulleung Basin (울릉분지에서의 선상중력과 위성중력 통합에 의한 중력 해상도 향상 및 해석)

  • Park, Chan Hong;Kim, Jeong U;Heo, Sik;Won, Jung Seon;Seok, Bong Chul;Yu, Hae Su
    • Journal of the Korean Geophysical Society
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    • v.2 no.1
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    • pp.27-38
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    • 1999
  • The errors between track segments or at the cross-over points of shipborne gravity were successfully reduced by applying a cross-over error adjustment technique using satellite gravity. The integration of shipborne and satellite altimeter-implied free-air gravity anomalies after the cross-over error adjustment resulted in a high resolution gravity map which contains both short and long wavelength components. The successful adjustment of the cross-over errors in the shipborne gravity using the satellite gravity suggests that the shipborne gravity can be combined with the satellite anomalies characterized by a stable and long wavelength component. The resulting free-air anomaly map is evenly harmonized with both short and long wavelength anomalies. Thus the corrected anomaly map can be better used for the geological interpretation. Free-air anomalies with more than 140 mGal in total variations generally correspond to the seafloor topographic changes in their regional patterns. A series of gravity highs are aligned from the Korea Plateau to the Oki Island, which are interpreted to be caused by seamounts or volcanic topographies. The gravity minima along the western and southern shelf edge are associated not only with the local basement morphology and thick sediment fill at the continental margin, but also possibly with the crustal edge effect known for passive continental margins. Series of NE-trending linear anomalies are possibly caused by a swarm of volcanic intrusions followed the initial opening of the Ulleung Basin. The linear high anomalies in the Ulleung Plateau are terminated by the straightly NNW-trending anomalies with a sharp gradient in its western boundary which indicates a fault-line scarp. The opposite side adjoined with the fault-line scarp shows no correlation with the fault-line scarp in geometry indicating that the block might be horizontally slided from the north. A gravity high in contrast to the deepening in seafloor toward the northeastern central Ulleung Basin is probably responsible for the thin crust and shallow seated mantle. The gravity minima along the western and southern shelf edge are associated not only with the local basement morphology and thick sediment fill at the continental margin, but also possibly with the crustal edge effect known for passive continental margins. Series of NE-trending linear anomalies are possibly caused by a swarm of volcanic intrusions followed the initial opening of the Ulleung Basin. The linear high anomalies in the Ulleung Plateau are terminated by the straightly NNW-trending anomalies with a sharp gradient in its western boundary which indicates a fault-line scarp. The opposite side adjoined with the fault-line scarp shows no correlation with the fault-line scarp in geometry indicating that the block might be horizontally slided from the north. A gravity high in contrast to the deepening in seafloor toward the northeastern central Ulleung Basin is probably suggestive of a thin crust and shallow seated mantle.

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Socio-medical Study on Gonorrhoea with Special References of Prevalence, PPNG and Antibiotic Resistance (임질환자(淋疾患者)에 관(關)한 사회의학적(社會醫學的) 연구(硏究) -유병률(有病率), PPNG 및 항균제내성(抗菌劑耐性)을 중심(中心)으로-)

  • Lee, Seong-Ho;Hwang, In-Dam;Park, Young-Soo;Koh, Dai-Ha
    • Journal of Preventive Medicine and Public Health
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    • v.16 no.1
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    • pp.41-50
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    • 1983
  • The incidence of sexually transmitted disease, especially gonorrhoea has risen despite the progress in its diagnosis and treatment. For the effective control programs of sexually transmitted disease, it should be required socio-medical approaches. A study on gonorrhoea and penicillinase-producing Neisseria gonorrhoeae(PPNG) was conducted in Jeonju and Kunsan area from March, 1982 through August, 1982. The 221 entertrainers were studied in order to determine the prevalences of gonorhoea and PPNG. Socio-demographic informations of the entertainers were obtained by interviewing them. Gonococci were cultured on Thayer-Martin enrichment media for isolation, and PPNG was confirmed using beta-lactamase reagent ($PADAC^{tm}$ Beta-Lactamase Test Strips, Galbiochem-Behring). The results of the study are summarized as follows; 1. The average age of the entertainers studied was $26.1{\pm}4.7$ years. 2. The average years of working in entertaining business was $2.4{\pm}1.4$ years, and the average income per month was $239,592{\pm}90,480$ won. On the education level, 70.6% of the entertainers were middle or high school graduates 3. 47.5% of the entertainers were using contraceptives. 90.5% have experienced artificial abortion. 4. 37(16.7%) out of 221 entertainers were revealed to gonorrhoea, and 13 (35.1%) of gonorrhoea patients were by PPNG. 5. The prevalence rates of gonorrhoea and the proportion of PPNG by age were not significant statistically. Meanwhile, the colelations between the rates of gonorrhoea and education, frequency of love-making with customers and type of sexual partner were highly significant statistically. 6. 37 strains of gonococci isolated were almostly resistant to several antimicrobial agents, especially amikacin, clindamycin and chloramphenicol. Furthermore PPNG strains were completely resistant to not only above drugs but also penicillin.

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Photodynamic Therapy with Photofrin Reduces Invasiveness of U87 Malignant Human Glioma Cells (교모세포종 세포주 U87에서 Photofrin을 사용한 광역학 치료가 종양 침습성에 미치는 영향)

  • Woo, Hye Kyung;Cho, Kyung-Keun;Rha, Hyung Kyun;Lee, Kyung Jin;Park, Sung Chan;Cho, Jung Ki;Park, Hea Kwan;Kang, Joon Ki;Choi, Chang Rak
    • Journal of Korean Neurosurgical Society
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    • v.30 no.sup2
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    • pp.189-196
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    • 2001
  • Objective : We tested the hypothesis that photodynamic therapy(PDT) with Photofrin inhibits tumor invasion of U87 human glioma cells using several in vitro assay to measure tumor invasiveness. The effects of PDT on cell growth, directional migration and cell invasion were investigated. Material and Method : Tumor cells were treated with Photofrin at various doses and at a fixed optical(632nm) dose of $100mJ/cm^2$. Cytotoxicity was tested using the MTT method. Invasion assays including the matrigelartificial basement membrane barrier migration and spheroid confrontation with confocal microscopic analysis were used to study the relationship between PDT and invasiveness. Result : U87 cells showed a dose dependent cytotoxic response to increasing Photofrin dose. Data from the matrigel artificial basement membrane assay indicate that PDT inhibits the U87 cell migration dose dependently. Low doses of subcytotoxic PDT treatment, such as 2.5ug/ml Photofrin dose, also appeared to significantly inhibit migration of U87 cells(p<0.05). In co-cultures between U87 cell spheroids and brain aggregates, progressive invasion with destruction of the brain aggregate occurs. The extent of tumor cell infiltration and proportion or intact brain aggregate remaining after 24h differs in Photofrin PDT treated versus Photofrin only control, with changes suggestive of a dose-response effect. Conclusion : our data indicate that PDT with Photofrin significantly inhibits the invasiveness of U87 cells, and this inhibition is dose dependent.

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Effects of Horticultural Therapy on the Improvement of the Self-Esteem and Sociality of Mentally Retarded Persons (원예치료프로그램의 적용이 정신지체장애인의 자기주장 및 사회성 향상에 미치는 영향)

  • 박민희;차영주;유영원;부희옥;이숙영
    • Korean Journal of Plant Resources
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    • v.17 no.3
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    • pp.339-351
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    • 2004
  • This study was conducted to evaluate the effect of phased horticultural therapy(HT) program on the experience of psychologic therapy and the development of job and social integration in the mentally handicapped persons. In this study, the mentally handicapped persons participated in HT program were chosen in disabled person's welfare institute of Jeonnam. HT program was performed twice a week with 1 hour activity for 4 months. As a results, the mentally handicapped persons participated in HT program showed high interest of horticulture and improvement of self-respect and the high satisfactory degree of HT program. Therefore, the mentally handicapped persons were showed the experience of both physical and mental therapy, improvement of self-esteem scale and sociality in HT program. Also, the application of HT program with continuously interest will be showed high improvement of physical, psychological and sentimental. In the course of this HT program progress, horticultural therapist and social welfare officer were showed the limitation of role. Therefore the leaders of group for successful HT program be required the comprehensive plan of more efficient HT program and induced technique of continuously up-phased improvements in HT program progress.