• 한국대기환경학회지
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• 제3권2호
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• pp.18-26
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• 1987

In order to investigate the character of air pollution by heavy metals and to elucidate the possible sources in Seoul city, this study was performed to measure the concentrations of heavy metals of total suspended particulate and air pollutants such as $SO_2, NO_2, CO, CH_4$, Non-methane hydrocarbon, ozone at the residential-traffic area (shinchon dong) in January and February, 1986. The results are as follows: 1. $SO_2$ and TSP concentration were 135ppb and 167 $\mug/m^3$ in average, respectively. 2. While concentrations of heavy metals such as Fe, Cu, Pb in the ambient air seems gradually decreasing annually, Ni compound has been shown the tendency of increasing. 3. Among heavy metals in TSP analysed, the iron was detected at the highest level, 0.905% and the cadimium was the lowest 0.004% in average, respectively. 4. V, Fe and Zn compounds in air were observed to be highly correlated with their correlation coefficients(r) higher than 0.7. Pb compound was highly correlated to the levels of Zn and Fe, however relatively less correlated to V compound. 5. Among concentrations of heavy metals in the particulates, V and Ni compounds were highly correlated with coefficient(r) of 0.8587; the cause might be imagined by the fact of releasing from combustion of fuel oil. Fe, Pb and Zn compounds were highly correlated $SO_2$ concentration. It might be explained that they were released by combustion of coal. 6. The level of $SO_2$ was highly correlated to most of heavy metals: especially correlation coefficient(r) to Pb compound was 0.9081. Pb compound was also highly correlated to NO, CO and TSP. TSP showed higher correlation to Pb and Cd compounds than to V and Ni compounds. It might be assumed that particulate was mainly produced by combusting coal from space heating and by exhausting gasoline and diesel oil from transportation rather than by burning fuel oil.

• Preventive Nutrition and Food Science
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• 제10권3호
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• pp.262-266
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• 2005

Soybean has been favored by many Thai people and it has been prepared by numerous different methods. Collected samples are as follows: Thua-nao paste from Chiangrai province, dried Thua-nao for Jatujak Market, Bangkok, 3 types of commercial soybean paste, soybean sauce and 2 types of fermented soybean curd cakes with other ingredients. Moisture contents of fresh and dried Thua-nao were 68.5 and $7.6\%$, respectively; therefore the shelf-life of dried Thua-nao can be extended to 1 year with proper packaging. The remainder of the soy foods had moisture contents of 55.4 to $64.4\%$. Fat contents of fresh and dried Thua-nao were 7.4 and $19.7\%$, respectively, whereas other samples contained less than $3\%$. Dried Thua-nao had the highest CHO (carbohydrates) content $(37.4\%);$ in contrast, soybean sauce contained only $4.5\%$. Calcium content was highest in dried Thua-nao followed by fresh Thua-nao; the other fermented soy foods had less than 44.7 mg/l00 g. Salt was added to samples other than Thua-nao resulting in high Na contents. Free and total daidzein contents of dried Thua-nao were 355 and 676 ug/g; similarly free and total genistein contents were 293 and $616.5\;\mug/g$, respectively.

• International Journal of Oral Biology
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• 제36권3호
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• pp.123-128
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• 2011

The notion that dental amalgam is a potential source of mercury exposure remains a controversial issue. However, there are few epidemiological analyses that have addressed whether this occurs in children. We aimed in our current study to identify the relationship between dental amalgam filling surfaces and the blood mercury levels in a cohort of 711 South Korean children aged between 8-9 years. Oral examinations were conducted to detect the number of amalgam filling surfaces on the teeth of these individuals. Blood samples were also taken from these children to assess the levels of mercury accumulation in the body. The amalgam filling surfaces were classified into four groups based on their number: 0 (n = 368), 1-5 (n = 219), 6-10 (n = 89), and 11+ (n = 35). The blood mercury levels in the children with more than 10 amalgam surfaces was 0.47 ${\mu}g$/L higher on average than those with no amalgam surfaces after adjusting for the frequency of fish or seafood consumption, age, and gender (P < 0.05). We found from our data that a higher number of dental amalgam fillings correlated with a higher blood mercury level in Korean children. Further studies are needed to investigate whether these elevated mercury levels exert neurotoxic or nephrotoxic effects.

• Human Ecology Research
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• 제58권4호
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• pp.483-496
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• 2020

This study examined the effects of eating alone, meal type, and dietary lifestyles on healthy eating capability of one-person households. We analyzed the mediation effects of weekly frequencies of each meal type taken by one-person households between eating habits such as eating alone and dietary lifestyles of one-person households and healthy eating capability. We also analyzed data from the 2019 Food Consumption Behavior Survey using a sample of 688 one-person households. Factor analysis, latent profile analysis, structural equation model analysis was conducted; direct and indirect effects of independent variables were tested using bootstrap method. The major results were as follows. Frequency of eating alone was about 10 times a week on average; one-person households had home-made meals about 12 times a week, for restaurant meals, 4 times, for delivered/take-out food, 0.39 times, and for other types, 0.44 times. Weekly frequencies of eating alone and meal types taken by one-person households were significantly different among the different socio-demographic groups. Dietary lifestyle was classified into four classes: traditional, health ignorant, food lifestyle ignorant, and balanced. Eating alone and dietary lifestyle had a significant effect on weekly frequency of each meal type. Frequencies of eating alone, balanced dietary lifestyle, and taking home-made meals had a positive direct effect on healthy eating capability, and frequency of taking delivered or take-out food and food consumption ignorant lifestyle had a negative direct effect. Eating alone, balanced and traditional dietary lifestyles had a positive indirect effect through the meal type; however, watching Mug-bang had a negative indirect effect.

• 한국대기환경학회지
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• 제2권3호
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• pp.57-63
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• 1986

Atmospheric particulate matter (A.P.M.) was collected on quartz fiber filters from March 1985 to May 1986 according to particle size using Andersen high-volume air sampler, and 6 heavy metals (Fe, Mn, Cu, Ni, Zn, Pb) in these particulates were analyzed by atomic absorption spectrophotometry. The arithmetic mean concentration of A.P.M. was 195.57$\mug/m^3$. The arithmetic mean concentrations of 6 metals (Fe, Mn, Cu, Ni, Zn and Pb) were 3385.04, 1451.67, 897.94, 159.68, 127.14 and 59.49 $ng/m^3$ respectively. The order of heavy metals contributing to A.P.M. was as follows: Fe > Zn > Pb > Cu > Mn > Ni. These heavy metals were devided into 3 groups according to their particle size distribution. The contents of heavy metals belonging to the 1st group (Fe, Mn) were increased with the particle size. On the contrary, the content of Pb belonging to the 2nd group (Pb) was increased with the decrease in the particle size. The heavy metal contents in the 3rd group (Ni, Cu, Zn) were lowest in the particle size range of 2.0-3.3 $\mum$ compared with particles larger or smaller tha this range. The seasonal variation of heavy metal concentration were as follows: Fe and Mn contents were highest in spring, but Ni and Pb contents were highest in winter. Statistical analysis showed that there was a significant correlation between A.P.M. and Fe in coarse particles, meanwhile between A.P.M. and Pb in the case of fine particles.

• KSBB Journal
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• 제14권1호
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• pp.9-16
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• 1999

Transforming growth factor $\beta$1(TGF-$\beta$1)은 여러 가지 생물학적 활성을 가지는 관계로 의학적 치료제로서 사용될 가능성이 크다. 본 연구에서는 혈소판추출, 젤여과, 양이온교환 크로마토그래피 및 역상 HPLC등 네 단계의 정제과정으로 이루어져 있는 정제공정을 이용한 TGF-$\beta$1을 값싸고 효울적으로 정제하였다. 이 과정을 거쳐 최종적으로 얻어진 TGF-$\beta$1은 비환원조건하에서 SDS-PAGE를 행한 결과 구매된 TGF-$\beta$1 표준품과 일치한 위치에서 한 개의 band가 관찰되어 순수하다는 것을 확인하였으며 또한 이것이 Westem blot를 통하여 TGF-$\beta$1 항체와 결합하는 것으로부터 TGF-$\beta$1임을 확인하였다 또한, mink lung epithelial cell line 을 이용한 성장저해 실험을 통해 정제된 TGF-$\beta$1이 구매되TGF-$\beta$1 표준품보다 조금 높은 활성을 가지는 것을 확인하였다 최종적으로 농축혈소판 10단위로부터 약 3.7$\mu$g의 정제된 TGF-$\beta$1이 얻어져 그 최종수율은 약 21%였다.

• 생명과학회지
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• 제15권5호
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• pp.796-801
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• 2005

국내산 산죽잎을 methanol로 추출하여 천연 항산화제로서의 이용성을 조사하기 위하여 여러 방법으로 항산화 활성을 측정하고 안정성에 대해 조사하였다. 산죽잎 메탄올 추출물은 0.1 mg/l에서 0.8mg/ml의 범위에서 농도 의존적으로 항산화활성이 증가하였다. 산죽잎 메탄올추출물은 DPPH radical 소거능에 대한 $IC_{50}$ 값은 $583{\mu}g/ml$, SOD 유사활성능에 대한 $IC_{50}$값은 $800{\mu}g/ml$, hydrogen peroxide 소거능에 대한 $IC_{50}$값은 $38{\mug}/ml$이 었으며 대조구로 사용한 BHT의 각각 의 $IC_{50}$값은 $271{\mu}g/ml,{\;}680{\mu}g/ml,{\;}30{\mu}g/ml$이었다. 산죽잎 메탄올추출물의 자동산화 억제능은 상기 농도 범위에서 $55\∼60\%$의 억제효과를 나타내었다. 산죽잎 메탄올추출물의 pH 안정성은 pH 6에서 안정하였으나 산성이나 알카리성으로 갈수록 pH 안정성은 떨어졌다. 산죽잎 메탄올추출물의 열안정성은 $0^{\circ}C$에서 $120^{\circ}C$의 온도범위에서 $80\%$ 이상의 항산화능을 유지하였다.

• 대한화학회지
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• 제26권1호
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• pp.36-42
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• 1982

대기중의 암모니아가스와 암모늄염의 필터포집법에 관하여 연구하였다. 표준가스 발생장치로 발생시킨 암모니아가스를 3% 붕산-25% 글리세린 혼합액이 스며든 유리섬유 필터에 포집하였다. pH조절법으로 발생시킨 암모니아가스와 대기중의 암모니아를 5회씩 포집하여 측정한 결과 포집효율은 각각 96.4${\pm}$ 2.15%와 97.4${\pm}$1.06%였다. 시판되는 유리섬유 필터 및 Polycarbonate 필터에 대하여 암모니아가스의 흡착 및 탈리현상을 검토한 결과 유리섬유 및 석영 섬유 필터에서는 암모니아가스의 흡착과 약간의 암모늄염이 탈리되었으나, Polycarbonate 필터는 대기중의 암모늄염을 포집하는데 적합한 것으로 판단되었다. 지름 47mm의 필터에 20l/min의 유량으로 60분동안 대기를 포집하여 인도페놀법에 의한 분광광도법으로 측정 할 경우, 측정가능한 암모니아가스의 최저농도는 0.83ppb (약 0.63$\mug$/$m^3$)이다. 이 방법은 종래의 용액포집법에 의한 분광광도 측정법에 비하여 감도가 20배나 높으므로 대기중의 암모니아 농도의 변화를 단시간(약 60분)내에 측정할 수 있다.

• 식물병연구
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• 제8권3호
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• pp.166-170
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• 2002

2000년 가을에 경기도 수원의 녹두재배포장에서 흰가루병이 발생하여 병원균의 형태 등을 조사하였다. 병징은잎의 앞면, 뒷면과 잎자루에서 흰가루의 균총이 형성되어서 진전됨에 따라서 잎이 황화되어 말라서 결국 낙엽이 되었다. 이 병원균의 분생포자는 분생자경의 끝에 연쇄적으로 생기며, 무색, 단세포, 타원형내지 장타원형으로 피브로신체를 가지고 있으며, 그 크기는 25~38$\times$16~22 $\mu\textrm{m}$ 이었다. 분생포자의 발아관은 단순발아관이며, 부착기는 뚜렷하지 않았고, 분생자경은 거의 수직으로 분지하였고, 기부는 대부분 직선상이었으며, 그 길이는 67~100 $\mu\textrm{m}$ 이었다. 기부세포는 길이가 37~65 $\mu\textrm{m}$, 폭이 10~11 $\mu\textrm{m}$ 이었다. 그리고 부착기는 뚜렷하지 않았으며, 발아관은 단순형이며 분지하지 않았다. 폐쇄자낭각은 구형이나 편구형으로 크기가 85~1130 $\mu\textrm{m}$이며, 부속사는 6-11개이며, 격막이 1~7개, 크기가 192~223$\times$5~7 $\mu\textrm{m}$ 이었다 벽세포는 불규칙다각형으로 15~45$\times$7~26 $\mu\textrm{m}$의 크기이며, 폐쇄자낭각은 하나의 자낭을 가지고 있으며, 자낭은 계란형 또는 반구형으로 8개의 자낭포자를 가지고 있으며, 크기는 62~95$\times$50~67 $\mu\textrm{m}$이었다. 자낭포자는 난원형 또는 반구형으로 크기가 16~24$\times$12~16 $\mu\textrm{m}$ 이었다. 이상의 결과로 Sphae개theca phaseoli 의한 녹두흰가루병으로 동정되어 국내에서 처음으로 보고한다.

• Journal of Preventive Medicine and Public Health
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• 제38권1호
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• pp.71-81
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• 2005

Objective : To elucidate the correlates of self-rated fatigue in Korean employees. Methods : The data for 10,176 (men, 7,984; women, 2,192; mean age, 34.2; SD: 8.8) employees recruited from a nationwide sample were examined. A structured questionnaire was used to measure the participants' fatigue, sociodemographics (sex, age, education, and marital status), job-related characteristics (work duration, grade at work, work hours, shiftwork, employment type, and magnitude of workplace), and health-related habits (smoking, drinking, coffee intake, and exercise). Two types of measurement for fatigue were used to evaluate the magnitude of fatigue: self-rated question and a standardized measurement tool (Multidimensional Fatigue Scale: MFS). Results : According to the self-rated fatigue, 32% of employees reported that they felt fatigue for the past two weeks, and 9.6% of males and 8.7% of females had experienced excessive fatigue (6 months or more). Hierarchical multiple regression analysis showed that fatigue measured by MFS was more common in women, younger, college or more graduated, single, and employees who do not regularly exercise. Fatigue was also associated with long work hours, and the size of the workplace (<1,000 employees). Conclusions : These results suggest that fatigue has been considered as a common complaint, and that it is affected by job-related factors like work hours and the workplace size as well as sociodemographics or health-related behaviors. Further research is needed to clarify the effects of fatigue on adverse health outcomes, work performance, work disability, sick absence and medical utilization, and to examine the relationship of job characteristics (e.g.: work demand, decision latitude) to fatigue.