• Journal of Preventive Medicine and Public Health
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• 제41권3호
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• pp.147-152
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• 2008

Objectives : Fluoridation of drinking water is known to decrease dental caries, particularly in children. However, the effects of fluoridated water on bone over several decades are still in controversy. To assess the risk of hip fracture related to water fluoridation, we evaluated the hip fracture-related hospitalizations of the elderly between a fluoridated city and non-fluoridated cities in Korea. Methods : Cheongju as a fluoridated area and Chungju, Chuncheon, Suwon, Wonju as non-fluoridated areas were chosen for the study. We established a database of hip fracture hospitalization episode based on the claims data submitted to the Health Insurance Review Agency from January 1995 to December 2002. The hip fracture hospitalization episodes that satisfied the conditions were those that occurred in patients over 65 years old, the injuries had a hip fracture code (ICD-9 820, ICD-10 S72) and the patients were hospitalized for at least 7days. A total of 80,558 cases of hip fracture hospitalization episodes were analyzed. Results : The admission rates for hip fracture increased with the age of the men and women in both a fluoridated city and the non-fluoridated cities (p<0.01). The relative risk of hip fracture increased significantly both for men and women as their age increased. However, any difference in the hip fracture admission rates was not consistently observed between the fluoridated city and the non-fluoridated cities. Conclusions : We cannot conclude that fluoridation of drinking water increases the risk of hip fracture in the elderly.

• Journal of Microbiology and Biotechnology
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• 제22권6호
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• pp.754-762
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• 2012

Colbricon Superiore and Inferiore are two small adjacent high-mountain lakes located in the Paneveggio Natural Park (Italy) that offer the rare opportunity to study two iso-ecologic water environments differing only by area and volume in a ratio of 2:1 and 3:1, respectively. We took advantage of this setting to investigate phytoplankton dynamics, compare variability and productivity differences between the two basins, and assess size-dependent issues. The phytoplankton group of the Dinophyceae was chosen as the indicator organisms of ecological perturbation owing to their high sensitivity to environmental variations, as well as their acknowledged nature of versatile proxy to report global climatic changes. The study was conducted for over 10 years with fortnightly samplings. Results indicated that (a) the Dinophyceae communities in the smaller lake were significantly more resistant to changes exerted by the fluctuation of lakewater transparency and pH; and (b) the smaller lake sustained a consistently higher production with an average Dinophyceae density 1.73 fold higher than that of the larger lake. The coefficients of variation show that the chemical parameters in the smaller lake display higher time-related fluctuation while being spatially homogeneous and that such conditions correlate with a higher stability of the Dinophyceae assemblage. The use of this setting is also proposed as a model to test relationships between ecosystem production and physical stability.

• Applied Microscopy
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• 제14권2호
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• pp.66-80
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• 1984

The organic phosphorus compounds have been widely used as an insecticide, since toxicity of these compounds is especially drastic to the insects than to men and other mammals. The organic phosphates are rapidly hydrolized and hence have little cumulative and ecologic effects. However, due to their acute toxic effects organophosphate have recorded rather high fatalities in men and domestic animals. The organic phosphorus compounds are powerful inhibitors to the carboxylic esterase enzymes such as acetylcholinesterase and pseudocholinesterase. As a result of firm binding characteristics of phosphate radicals to the active sites of enzyme, the activities of these enzymes are inhibited by the organophosphates. The organophosphates such as diazinon is easily observed from skin, gastrointestinal tract, conjunctivas and respiratory tract, and it is converted to more toxic form during metabolism in the liver The present study was carried out in order to investigate the hepatotoxicity of diazinon by observing the changes in the ultrastructure of cytoplasmic organelles of hepatic cells in albino mice. The animals were killed at 6, 12 and 24 hours after administration of 25mg/kg diazinon. The piece of hepatic tissue obtained from each animal was ultrathinly sectioned. The specimens stained by uranyl acetate and lead citrate double contrast methods were observed with JEM model 100B electron microscope. The results obtained were as follows: 1) A prominent dilatation and sacculation of the cisternae of rough endoplasmic reticulum associated with detachment of membrane bound-ribosomes, and disaggregation of the free ribosomes were recognized. 2) The hypertrophy of the smooth endoplasmic reticulum associated with depletion of the glycogen particles was observed. 3) The atrophy of cisternae of Golgi complex was observed. 4) A large number of secondary lysosomes (autophagic vacuoles and residual bodies) were formed. Consequently it is suggested that diazinon would induce disorganization of the cytoplasmic organelles of hepatocytes in albino mice.

• 한국지역지리학회지
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• 제7권2호
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• pp.82-96
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• 2001

본 연구에서는 우리나라의 대표적인 조간대 퇴적지형인 강화도 남단 갯벌을 사례로 서해안 조간대 지역의 퇴적환경을 구명하고 올바른 이용 및 관리방안을 고찰하였다. 연구결과는 다음과 같다. 첫째, 강화도 남단 갯벌은 세계적으로 그 가치가 인정되고 있는 지형 생태적으로 중요한 해안습지이다. 그러나 해안생태계의 자정작용 역할을 하는 염생습지의 대부분은 간척되어 현재는 농경지로 이용되거나 그대로 방치되고 있다. 둘째, 강화도 남단 갯벌의 평균 조석간만의 차는 7.3m로, 조석차를 바탕으로 권역을 구분하면 고위 조간대 중위 조간대 저위 조간대 및 천해로 구분 지을 수 있다. 또한 대부분 간척된 과거 염생습지로 이루어진 육지권역이 포함될 수 있다. 셋째, 연구지역의 퇴적환경을 지시한다고 판단된 표층 퇴적물의 물리적 특성을 분석한 결과 평균 입도 분포는 모래 41.5% 실트 47.3% 점토 11.2%로 나타나서 실트의 비율이 상당히 높은 비율을 차지하고 있는데, 이는 퇴적물의 생태적 특성을 지시하는 것이다. 넷째, 권역별 이용 및 관리방안으로는 (1) 고위 및 중위 조간대는 갯벌 체험학교와 인공 염생습지, 그리고 양식업 대상지로 이용할 수 있으며 오염물질의 유입과 양식장 관리가 중요한 곳이다. (2) 저위 조간대는 특정기간의 갯벌체험과 바다 낚시 대상지로 이용할 수 있으며 조류의 통과시기와 패류의 산란시기에는 각별한 주의가 요구되는 곳이다. (3), 천해는 외해와 인접한 곳으로서 극히 일부 기간의 갯벌 체험과 바다 낚시 대상지로 이용할 수 는 곳이다. (4) 인접 육지부는 방조제를 이용한 철새관찰용 시설물 설치와 갯벌의 생태적 특징을 중심으로 한 홍보물을 설치할 수 있는 생태 관광지 대상지이다. 또 갯벌부로 유입되는 생활하수와 축산폐수의 관리가 중요한 곳이기도 하다.

• 한국지구과학회지
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• 제34권3호
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• pp.235-248
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• 2013

본 연구는 대도심에 위치하는 야산을 지질학습장으로 활용할 수 있는가에 대한 조사이다. 이를 위해 광주광역시 서구에 위치한 높이 305 m의 금당산을 대상으로 인문 및 자연지리, 지질학적 특성, 지형요소, 경관, 야외학습을 위한 편의성 등을 검토하였다. 금당산 주변의 반경 5 km 이내에 거주하는 인구는 약 62만 명 정도이며, 이 중 학생과 교원은 약 17만 명이다. 연구지역은 강수일이 적고, 온화한 날씨가 많아 학습장으로 활용하기에 적합한 기후를 가지고 있다. 금당산에 접근하는 도로망과 대중교통도 매우 편리하다. 금당산에서는 다양한 암석과 지질구조를 관찰할 수 있다. 연구지역의 기반을 이루는 광주화강암은 중생대 쥐라기의 심성암체이다. 이 지역에는 백악기의 그래노파이어(미문상화강암)와 층상응회암, 라피리응회암, 유문암과 같은 여러 가지 화산암이 분포한다. 다양한 중성 및 산성 암맥이 절리를 따라 관입하고 있다. 금당산에는 U자형의 지형, 다양한 크기와 방향의 절리, 단층, 엽리, 나마, 토르, 단애, 그루브, 암괴류, 암괴원, 풍화층과 새프롤라이트와 같은 다양한 지형요소가 있다. 금당산 주능선에서는 무등산 전체 모습과 시가지 전경, 풍암 호수와 월드컵경기장, 일출과 석양과 같은 아름다운 경관을 감상할 수 있다. 또한 지질학과 연계할 수 있는 생태학습 시설이나, 야외학습을 위한 편의시설이나 응급의료시설도 잘 갖추어져 있다. 결론적으로 금당산은 지질학습장으로서 매우 양호한 조건을 갖추고 있다.

• 농촌의학ㆍ지역보건
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• 제45권4호
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• pp.183-193
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• 2020

이 연구는 생태학적 연구로서 EQ-5D index로 측정되는 건강수준의 시군구 단위 변이를 파악하고 지역사회건강조사 지표에서 이러한 변이를 설명하는 요인을 탐색하고자 하였다. 2017년도 지역사회건강조사자료에서 산출되는 전국 229개 시군구의 EQ-5D index 변이는 EQ(격차비) 1.1배, CV(변이계수) 1.0으로 지역 간 변이는 연구에 포함된 독립변수들에 비해 상대적으로 작았다. EQ-5D index 값이 전국 하위 25%에 속하는 시군구 비중이 높은 광역시도는 전라북도(9개 시군, 64.3%)와 충청남도(7개 시군, 46.7%)이었다. 다중 선형회귀분석 결과 지역 간 변이의 주요요인으로 우울감 경험률, 스트레스 인지율, 자살 생각률, 관절염진단 경험률 등이 도출되었다. 지역 간 건강수준의 격차를 줄이기 위해서는 사회심리적 요인들을 포함한 상기 요인들의 개선에 우선순위를 두어야 할 것으로 사료된다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권5호
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• pp.2465-2473
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• 2016

Background: This study aimed to investigate the standardized incidence and mortality rate of colorectal cancer and its relationship with the human development index (HDI) across the world in 2012. Materials and Methods: This ecologic study was conducted for assessment of the correlation between age-specific incidence rate (ASIR) and age-specific mortality rate (ASMR) with HDI and its components. Data for SIR and SMR for every country for the year 2012 were obtained from the global cancer project. We used a bivariate method for assessment of the correlation between SIR and SMR and HDI. Statistical significance was assumed at P<0.05. Statistical analyses were performed using SPSS (Version 22.0, SPSS Inc.). Results: Countries with the highest SIR of colorectal cancer in the world in 2012, were Republic of Korea, Slovakia, Hungary and countries with the highest SMR were Hungary, Croatia and Slovakia. The correlation between SIR of colorectal cancer and the HDI was 0.712 ($P{\leq}0.001$), with life expectancy at birth 0.513 ($P{\leq}0.001$), with mean years of schooling 0.641 ($P{\leq}0.001$) and with level of income per each person of the population 0.514 (P=0.013). In addition, the correlation between SMR of colorectal cancer and the HDI was 0.628 ($P{\leq}0.001$), with life expectancy at birth 0.469 ($P{\leq}0.001$), with mean years of schooling 0.592 ($P{\leq}0.001$) and with level of income per each person of the population 0.378 (P=0.013). Conclusions: The highest SIR and SMR of colorectal cancer was in the WHO Europe region. There was a positive correlation between HDI and SIR and SMR of colorectal cancer.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.5987-5991
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• 2015

Our previous study detected aflatoxins in red chili peppers from Chile, Bolivia, and Peru, each of which have a high incidence of gallbladder cancer (GBC). Since the aflatoxin B1 concentration was not so high in these peppers, it is important to clarify the presence of other mycotoxins. Here we attempted to determine any associations between the concentrations of aflatoxins and ochratoxin A (OTA) in red chili peppers, and the corresponding GBC incidences. We collected red chili peppers from three areas in Peru: Trujillo (a high GBC incidence area), Cusco (an intermediate GBC incidence area), and Lima (a low GBC incidence rate), and from Chile and Bolivia. Aflatoxins and OTA were extracted with organic solvents. The concentrations of aflatoxins B1, B2, G1, and G2, and OTA were measured by high-performance liquid chromatography. The values obtained were compared with the incidence of GBC in each area or country. All of the red chili peppers from the three areas showed contamination with aflatoxins below the Commission of the European Communities (EC) recommended limits ($5{\mu}g/kg$), but the OTA contamination of two samples was above the EC recommended limit ($15{\mu}g/kg$). The mean concentrations of OTA in the peppers from Chile (mean $355{\mu}g/kg$, range < $5-1,059{\mu}g/kg$) and Bolivia (mean $207{\mu}g/kg$, range $0.8-628{\mu}g/kg$), which has a high incidence of GBC, were higher than that in Peru ($14{\mu}g/kg$, range < $5-47{\mu}g/kg$), which has an intermediate GBC incidence. The OTA contamination in the red chili peppers from Chile, Bolivia, and Peru was stronger than that of aflatoxins. Our data suggest that OTA in red chili peppers may be associated with the development of GBC.

• 한국지반환경공학회 논문집
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• 제10권7호
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• pp.125-133
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• 2009

하수를 정화하는 과정에서 발생하는 슬러지는 과거 주로 매립되어 왔으나, 2003년 유기성 슬러지의 매립금지라는 폐기물 관리법이 개정됨에 따라 최근에는 주로 해양투기 되어왔다. 그러나 '런던협약 96의정서'에 의해 2011년부터 해양투기도 금지될 예정이어서, 세계 각국은 슬러지의 다양한 처리방법에 대해 노력하고 있다. 우리나라도 예외 없이, 하수슬러지의 합리적인 처리방법을 찾기 위해 현재 많은 전문가들이 노력하고 있으며, 그중 하나가 재생 에너지화이다. 슬러지의 재생 에너지화의 성패는 친환경적이고 경제적인 건조방법에 달려 있다 해도 과언이 아니다. 따라서 본 연구에서는 영동군에서 발생하고 있는 하수슬러지를 재생에너지화하기 위해, 슬러지의 화학적 특성을 분석하여 에너지화 가능성을 검토하고, 마이크로파를 물과 슬러지에 각각 조사하여 슬러지의 건조 특성과 효율성 등을 분석하였다. 그 결과, 영동군하수 슬러지는 중금속 성분이 매우 적고 열량이 3,370kcal/kg 이상으로 재생에너지화하기에 적당함을 확인하였다. 또한, 마이크로파에 의한 슬러지 건조 특성을 분석한 결과, 슬러지 중량 대비 시간의 곡선은 투입 슬러지 량에 관계없이 늘어진 S자 형태의 거동특성을 보임은 물론 그 기울기가 일정함을 확인하였다. 또한, S 곡선을 변곡점 기준으로 세 영역으로 나눌 경우 두 번째 영역에서 건조가 가장 많이 일정하게 발생하며, 전체 건조량의 약 80% 이상임도 확인하였다. 본 결과는 향후 마이크로파를 이용한 full-scale 건조공정에서 투입 슬러지 대비 슬러지 건조량을 예측하는데 적용할 수 있다. 또한 본 실험 결과에 의하면, 마이크로파에 의한 건조능력이 약1.0kg/kW 이상을 보이고 있어 경제성도 갖고 있음을 확인하였다.

• 한국물환경학회지
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• 제33권5호
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• pp.511-524
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• 2017

This study was carried out for the purpose of creating a restoration plan to improve the ecological quality of the Changwon and Nam streams. Based upon the results of comprehensive diagnostic assessment, restoration priority was given to the upstream reach, where conservation status is relatively superior. Restoration level was usually determined to practice active restoration as conservation, and the states of both Changwon and Nam streams were not so good. Restoration plans, by reach, were classified into "upstream", "midstream", and "downstream" were suggested in both terms of horizontal section frame and vegetation-based on the result of diagnostic assessment and the reference information. "Upstream", "mid-stream" and the "downstream" of Changwon and Nam streams were classified into "small-gravel- mountainous", "small-sand-plain", and "small-clay-plain streams" respectively (based on scale, and substrate and slope of river bed). The spatial arrangement of vegetation was laid out in diagram form by reflecting micro-topography and the water level of the horizontal section of river. Information regarding species composition was recommended as dominant species, which appear frequently in three vegetation zones composed of herbaceous plants, shrubs and trees and sub-tree- dominated zones divided by reflecting disturbance regime, depending on position on the horizontal section of river. Moreover, there have been prepared not only plans to improve the terrestrial ecosystems around the streams but also plans to create ecological networks, which can serve to improve the ecologic quality of the whole regional environment by serving to connect streams and terrestrial ecosystems, a process probably necessary and definitely recommended to realize true (genuine) restoration. Plans for ecological parks and networks were prepared by mimicking the species composition of Alnus japanica community, Zelkova serrata community, Carpinus laxiflora community, Quercus aliena community, and Q. serrata community.