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Investigation of a Staphylococcal Food Poisoning Outbreak Among School Children (수학여행중 국민학교학생의 포도구균식중독 발생에 대한 역학적조사)

  • Loh, In-Kyu
    • Journal of Preventive Medicine and Public Health
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    • v.5 no.1
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    • pp.111-114
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    • 1972
  • There was an outbreak of food poisoning on the 17 October, 1970 among the primary school children who came from a rural area, Yeongi-gun, Choongcheongnam-do to Seoul City on an educational trip. Of the 199 children participating in the trip, 149 cases of food poisoning developed a 74.9% attack rate. The acute onset of symptoms, of abdominal pain, diarrhea, vomiting and headache which occurred 1-5 hours after eating their lunch suggests that the outbreak was due to staphylococcal food poisoning. The common source of food was identified as the lunch packed in a chip-box which were eaten on October 17 during the trip. Most probable kind of food of the lunch as the cause was the favoured fish paste. The lunch were prepared at restaurant A in Seoul City. One of the personnel of the restaurant had a unhealed cut wound on the third finger tip of the left hand, from which it was considered that the food was contaminated with Staphylococcus during preparation. The chance of multiplication of Staphylococcus to produce enterotoxin in the food might be existed during flavouring the food with some degree of heat, and also during about 10 hours elapsed before serving the food after preparation.

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Water Quality and Phytoplankton in the Waters of Manripo and Daechon Beaches (만리포 및 대천 해수욕장 수질 및 식물플랑크톤)

  • Yeo, Hwan-Goo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.6
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    • pp.2872-2878
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    • 2011
  • In spite of high concentrations of SS(>30mg/l) in July 2010, the water condition of Manripo was fine for swimming as COD data lower than 2.0mg/l in summer continuously. The bloom of phytoplankton or red tide were not occurred in the waters. COD data from the waters of Daechon were lower than 2.0mg/l, except August. Relatively high SS concentrations were the characteristics of Daechon beach and were caused by the effects of mud resuspension. The dominant taxa of phytoplnkton communities were consist of diatoms as the normal groups of neritic sea waters.

Water Quality and Phytoplankton in the Waters of Anmyondo Ggot-jee Swimming Beach (안면도 꽃지해수욕장 수질 및 식물플랑크톤)

  • Yeo, Hwan-Goo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.1
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    • pp.451-455
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    • 2012
  • Physicochemical water conditions and phytoplankton were investigated at Ggot-jee beach in Anmyondo, summer season of 2011. COD were sometimes recorded higher than 5.0mg/l and SS were always over 40mg/l. DO, pH and salinity were stable generally but low salinity was affected by heavy rainfall. In spite of relatively high concentrations of chlorophyll and phytoplankton standing stocks, discolored water phenomena(green or red tide) had not been occurred. A few dinoflagellate species were dominated in June and July, but general diatoms were dominant species of phytoplankton community in August. Escherichia coli concentrations were higher in August(>400CFU/100ml) than in July but it's not the level of hygienic problem.

A Study on Realizing the GUI Based Ocean Pollutant Information Simulator I (GUI 기반 해양오염원 정보제공 SIMULAIOR 구현에 관한 연구 I)

  • Rho J. H.;Yoon S. H.;Kim M. H.;Yoon B. S.
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.5 no.3
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    • pp.23-27
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    • 2002
  • Ocean pollution like as oil spill and red tide have occurred considerable and executing clean-up them. Rapid prediction of polluting area is necessary that efficiency clean-up. In this study, develop the program that clean-up worker could easy predict polluted area. This paper is introduced configuration and contents of ODM(oil diffusion modelling) which constructed with GUI(Graphic User Interface) system. ODM is consisted with pre, post and main process, and constructed on window process. So, clean-up worker easy operating program and confirm the result. Studying this program, the distribution of ocean pollutant and phase of ocean movement is shown without difficulty on a computer.

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Change of Growth and Blood Characteristics on Starvation of Red Seabream Pagrus major Cultured in Marine Net Cage in Summer (하절기 가두리양식 참돔의 절식에 따른 성장과 혈액성상의 변화)

  • Kim, Won Jin;Won, Kyoung Mi;Shin, Yun Kyung;Lee, Jeong Yong
    • Korean Journal of Ichthyology
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    • v.29 no.3
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    • pp.165-175
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    • 2017
  • To minimize the damage caused by summer season such as high temperature and red tide, this study was conducted to investigate the effect of feeding and starvation on the survival rate, growth, growth restoration and physiological response of red seabream Pagrus major which were reared in marine net cage ($6m{\times}6m{\times}6m$). The feeding group was fed throughout the experiment for 10 weeks, whereas starvation group was not fed for 6 weeks and subsequent refeeding for 4 weeks. Survival rates of feeding and starvation groups were 94.4% and 98.1% respectively. The growth rate of starvation group was significantly lower than feeding group during starvation period, but recovered rapidly after feeding. The nutritional status such as albumin, total protein, total cholesterol, triglyceride also showed similar tendency to the growth data. Hematocrit and hemoglobin levels were higher in the feeding group than the starvation group during starvation period. Aspartate aminotransferase, glucose and total cholesterol were rapidly increased at the same time (in 5 week) in feeding group, whereas starvation group did not significant difference during starvation period. It was shown that the feeding group is more sensitive to stress than the starvation group. Thus, starvation can be applied as a rearing management plan of net cage fish farm in summer season.

Relationship between Pollution Factors and Environmental Variation in Waters around Masan Bay (마산만 주변 해역에서 오염인자와 해양환경변동과의 관계)

  • Shin, So-Young;Lee, Chung-Il;Hwang, Sun-Chool;Cho, Kyu-Dae
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.10 no.2 s.21
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    • pp.69-79
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    • 2004
  • This study focuses on the relationship between pollution factors around Masan, Changwon and Chinhae city considerd as main pollution sources and marine environment in Masan bay of Korea. Water quality data measured In Jinhae bay and environmental investigation data in Masan, Changwon and Jinhae cities from 1981 to 1998 were used for this study. Annual means and standard deviations of COD, DIN and DIP concentrations from 1981 to 1998 showed that both their concentration and fluctuations were higher in the inner part of Masan bay (region A) than near Somodo (region B). Sediment dredging in Masan bay had been done from 1990 to 1994. After dredging, COD concentration has been decreasing In surface layer. Also water pollution was gradually spreaded from the inner part to the outer part of the bay due to the continuous inflow of domestic sewage and industrial wastewater. In the late of 1990s, the pollution was heavier. DIN and DIP concentrations were found to be increased by establishment of industry complex and decreased by sewage treatment plant near the city adjacent to Jinhae bay, 1993. The correlation between COD, DIN and DIP changes and neighbor cities' pollution sources were calculated From 1981 to 1998, correlation coefficient (r) was over 0.8 except for the bottom of region A From 1981 to 1998, r between the DIP concentration and population was over 0.65 except for the surface of region A, and the r between the DIP and the number of factories was over 0.6 too, in region B.

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Application of GOCI to the Estimates of Primary Productivity in the Coastal Waters of the East Sea (동해 연안역 일차생산량 추정을 위한 GOCI 자료 적용)

  • Choi, Jong-kuk;Ahn, Jae-Hyun;Son, Young Baek;Hwang, Deuk-jae;Lee, Sun Ju
    • Korean Journal of Remote Sensing
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    • v.36 no.2_2
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    • pp.237-247
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    • 2020
  • Here, we generated maps of primary production in the coastal waters of the East Sea using sea surface chlorophyll-a concentrations (CHL), photosynthetically available radiation (PAR), euphotic depth induced by GOCI along with sea surface temperature (SST) from satellites of foreign countries as input parameters, and carried out a sensitivity analysis for each parameters. On 25th of July in 2013 when a wide cold waters appeared and on 13th of August in 2013 when a big harmful algal bloom existed in the study area, it shows high productivities with averages 1,012 and 1,945 mg C m-2 d-1, respectively. On August 25, 2013, when the cold waters and red tide retreated, it showed an average of 778 m-2 d-1, similar to the results of the previous analysis. As a result of the sensitivity analysis, PAR did not significantly affect the results of the primary production, but the euphotic depth and CHL showed aboveaverage sensitivity. In particular, SST had a large influence to the results, thus we could imply that an error in SST could lead to a large error in the primary production. This study showed that GOCI data was available for primary production study, and the accuracy of input parameters might be improved by applying GOCI, which can acquire images 8 times a day, making it more accurate than foreign polar orbit satellites and consequently, it is possible to estimate highly accurately primary production.

Effect of Salinity-stratified Waters on Upward Migration and Ratio of Extracted DNA/RNA in Cochlodinium polykrikoides Margalef Based on the Ratio of Absorbance at 260 and 280nm (염분 구배가 Cochlodinium polykrikoides Margalef의 수직이동 및 DNA/RNA 비율에 미치는 영향)

  • Cho Eun Seob;Lee Young Sik
    • Journal of Life Science
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    • v.15 no.3 s.70
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    • pp.468-473
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    • 2005
  • The coastal regions of Yeosu, the South Sea of Korea, has occurred annually the red tide which is caused by potentially ichthyotoxic dinoflagellate C. polykrikoides, with a wide avenue for exchange with oceanic waters and freshwater runoff from Sumjin river. We attempted to examine the variability in response to vertical migration and concentration of extracted DNA/RNA of C. polykrikoides exposed to salinity-stratified waters. The experimental aquarium of the 60 liter was employed to culture C. polykrikoides. One aquarium was supplied with only sea water, the other was consisted of sea water and freshwater. Experiment was conducted for 5 days. In experimental column (mixture of freshwater and sea water), salinity was maintained to 20 at upper and approximately 30 at bottom during the period of this study. The fluctuation with related to dissolved oxygen and pH was similar pattern to both columns. Chlorophyll a was significantly higher value at upper than bottom. During 24h, chlorphyll a on experimental column was extremely high on the top as soon as lighting, compared with control. With elapsed time, the gap between experimental and control columns was a little. In darkness, chlorophyll a was not significantly different between upper and bottom, most cells appeared to randomly distribute on column regardless of water layer. Fluctuation with related to concentration of extracted DNA and RNA based on ratio of absorbance of 260 and 280 nm in experimental column was higher at final day or diel migration than control. These results implied that a large volume of freshwater could be associated with influence of concentration of DNA and RNA, in particular, rapid upward movement caused massive fish kills as soon as sunset.

Seismic Performance Evaluation of Masonry Walls Retrofitted with Semi-buried Lattice Reinforcement (조적식 구조물의 부분 매입식 격자철근 보강기법의 내진 성능 평가)

  • Kim, Sang Hyo;Choi, Moon Seock;Park, Se Jun;Ahn, Jin Hee
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.3
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    • pp.88-98
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    • 2011
  • Masonry structure is a style of building which has been widely applied as residential facilities of low and middle stories, commercial and public facilities etc. But it is possible to destroy by loss of adhesive strength or sliding when lateral forces, such as earthquake, occurs. This study proposes a seismic retrofit method for masonry structure and its seismic performance is demonstrated by shaking table test. Two specimens per each shaking direction were made, having out-of-plane(weak axis) and in-plane(strong axis) direction. External load of 1 ton was also applied for each specimen during the test, to model the behavior of reinforced masonry wall. As a result of shaking table tests, it is shown that the specimen applying the proposed seismic retrofit method showed acceptable behaviors in both of Korea building design criteria(0.14g) and USA seismic criteria suggested by IBC(0.4g). However, it was observed that stiffness of the specimen toward out-of-plane was rapidly decreasing when seismic excitations over 0.14g were loaded. In comparison of relative displacements, maximum relative displacement of specimens which were accelerated toward out-of-plane with 0.4g at once was 29~31% of maximum relative displacement when specimens were gradually accelerated from 0.08g to 0.4g, while the maximum relative displacement of specimens accelerated toward in-plane has similar value in both cases. Therefore, it is concluded that the wall accelerated toward out-of-plane is more affected by hair crack or possible fatigues caused by seismic excitation.

Luminance distribution of Illuminated Bridges by View Point (교량의 조망점에 따른 휘도분포 특성분석)

  • Choi, Yoon-Seok;Kim, Jeong-Tai
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2005.11a
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    • pp.73-78
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    • 2005
  • 본 연구에서는 서울시 한강에 위치한 교량을 대상으로 다양한 조망점에 따른 경관조명의 물리량을 측정하고 그 특성을 분석함으로써 동일한 연구대상에 대하여 조망점이 달라졌을 때 나타나는 물리적 변화를 통해 경관조명분야의 물리량평가방법론의 새로운 접근방법론을 제시하는 것이 목적이다. 이를 위하여 연구대상의 선정은 교량구조형식에 따라 분류하고. 경관조명이 설치된 교량 17개소 중 다양한 조망점과 현장측정의 편리성 등을 고려하여 광진교(거더교), 올림픽대교(사장교), 동작대교(트러스교), 동작대교(아치교)를 연구대상으로 선정하였다. 조망점은 한강둔치를 이용하는 방문객들이 바라보는 투시뷰, 교량주변 건축물에서 바라보는 건물뷰 그리고 교량 위를 이동하면서 바라보는 주행뷰로 구분하였다. 이러한 연구방법으로 도출된 결과는 동일한 경관조명연출을 토대로 교량별 조망점에 따른 휘도측정 및 분석에서 측정되는 각도, 거리, 방향에 따라 정형화된 비율은 아니지만 휘도값에 있어서 차이가 있다는 것을 확인 할 수 있었으며, 투시뷰와 건물뷰는 동일한 교량 구성요소를 갖고 있어 상호간 비교 분석이 가능하고 경관조명평가 요소로서 그 기능을 담당 할 수 있다고 판단되며, 주행뷰는 교량형식과 가로등의 영향을 많이 받으므로 평가요소로써 조망점을 활용하기에는 조금 더 깊은 연구가 선행되어야 할 것으로 보인다. 따라서 경관조명을 평가함에 있어 다양하게 바라보는 조망점은 조명연출로 인한 시각적 인식에 차이를 유발시킬 수 있어 경관조명을 평가할 때 다양한 조망점의 설정이 보다 객관적이고 정확한 분석이 가능할 것으로 판단된다.ridinium의 분포는 chlorophyll-a농도와 밀접한 관련성이 있었다. 담수적조의 현존량은 상류지역에서 $8.5\;{\times}\;10^3\;cell\;mL^L{-1}$로서 많았고, 댐부근의 하류지역($4.4\;{\times}\;10^2\;cell\;mL^L{-1}$)으로 갈수록 감소하는 양상을 보였다. 또한, 담수적조의 원인종으로 규조류 Synedra acus와 남조류 Microcystis aeruginosa도 소량관찰되었다. 저수지의 수질 부영양화 현상은 기존 경사사면형 농경지를 기반으로 조성되었으므로 저층으로부터 풍부한 영양환경을 내재하고 있었고, 담수 초기에 발생할 수 있는 가능성을 포함하고 있었다. 또한 유입수량의 부족과 현재 수질개선을 위해 적용하고 있는 수중폭기시설등의 물리적인 영향도 직 ${\cdot}$ 간접적으로 작용하였을 것으로 추정되었다 따라서 향후 이에 대한 중장기적인 모니터링이 필요하였고 유역과 저수지의 통합적인 수질관리계획 이 요구되었다.group으로, 용존산소량, 전기전도도, pH, 인산염이 정점 3, 4, 5에서 같은 group으로 묶였다.유의적인 CAT 활성 증가효과가 나타났고, 간조직의 시토졸 1획분에서는 대조군 대비 15${\sim}$27%의 CAT 활성 증가효과가 인정되었다. 이상의 결과에서 목초액의 장기간 투여는 간조직 중의 활성산소의 억제효과뿐만 아니라 방어시스템으로서 활성산소 제거효소의 역할도 충실히 수행하여 노화를 효과적으로 예방하고 억제할 수 있을 것으로 기

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