• 한국가축번식학회지
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• 제24권3호
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• pp.231-239
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• 2000

본 연구는 dioxin이 생체에 미치는 영향을 구명하고자 dioxin 10~40 $\mu\textrm{g}$/kg을 mouse에 2일간 투여했을 때 체중, 정자수와 정자활력, 정소중량, 장기중량에 미치는 영향을 조사하였다. 1. Dioxin 10, 20 $\mu\textrm{g}$/kg 투여군의 체중은 30.6$\pm$2.9~40.7$\pm$3.9g, 30.8$\pm$4.1~39.5$\pm$3.1g이었으며, 30, 40 $\mu\textrm{g}$/kg 투여군의 체중은 31.0$\pm$3.5~39.0$\pm$3.5g, 30.6$\pm$3.4~38.3$\pm$4.0g 으로서 대조군의 30.6$\pm$2.8~44.5$\pm$3.1g에 비해 약간 낮은 치를 나타냈으며 dioxin 투여량이 증가할수록 감소하는 경향을 나타냈다(p.0.05). 2. Dioxin 10~40 $\mu\textrm{g}$/kg을 각각 2일간 투여했을때 WBC수는 대조군에 비해 현저한 증가치를 나타냈고 RBC수는 대조군에 비해 다소 증가되었으나 유의한 변화는 인정되지 않았으며, Hb량과 PCV치 및 PLT수는 대조군에 비해 크게 증가된 경향을 나타냈다. 3. Dioxin 10, 20$\mu\textrm{g}$/kg을 투여군의 정자수는 112.5 $\pm$ 3.7 ~ 119.4 $\pm$4.2 $\times$ $10^{6}$$m\ell$, 103.9 $\pm$ 3.8 ~ 110.2 $\pm$ 3.6 $\times$ $10^{6}$$m\ell$이었으며, 30, 40 $\mu\textrm{g}$/kg 투여군의 정자수는 97.5 $\pm$ 3.4 ~105.7 $\pm$ 4.4 $\times$ $10^{6}$$m\ell$, 87.2 $\pm$ 3.7 ~ 98.5 $\pm$ 3.8 $\times$ $10^{6}$$m\ell$로서 대조군의 119.0 $\pm$ 4.3 ~ 120.7 $\pm$ 4.8 $\times$ $10^{6}$$m\ell$에 비해 현저히 감소된 정자수를 나타냈다(p<0.05). 4. 정자활력은 10, 20, 30, 40 $\mu\textrm{g}$/kg을 각각 2일간 투여했을 때 69.4 $\pm$ 3.0 ~ 86.6 $\pm$ 4.7%로서 대조군의 93.0 $\pm$ 3.6 ~ 94.7 $\pm$ 4.2%에 비해 정자의 활력이 현저히 감소되었다(p<0.05). 5. Dioxin 10, 20, 30, 40 $\mu\textrm{g}$/kg을 각각 2일간 투여했을 때 정소중량은 대조군에 비해 약간 감소된 경향을 나타냈다. 6. Dioxin 10, 20, 30, 40 $\mu\textrm{g}$/kg을 각각 2일간 투여했을 때 신장, 비장 및 간의 중량은 정상대조군과 비교할 때 약간의 증가를 나타냈다.

• 한국입자에어로졸학회지
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• 제19권4호
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• pp.111-128
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• 2023

Chungcheongnam-do has various emission sources, including large-scale facilities such as power plants, steel and petrochemical industry complexes, which can lead to the severe PM pollution. Here, we measured concentrations of PM₁₀, PM_2.5, and its metallic elements at a suburban site in Taean, Chungcheongnam-do from September 2017 to June 2022. During the measurement period, the average concentrations of PM₁₀ and PM_2.5 were 58.6 ㎍/m³ (9.6~379.0 ㎍/m³) and 35.0 ㎍/m³ (6.1~132.2 ㎍/m³), respectively. The concentration of PM₁₀ and PM_2.5 showed typical seasonal variation, with higher concentration in winter and lower concentration in summer. When high concentrations of PM_2.5 occurred, particulary in winter, the fraction of Zn and Pb components considerably increased, indicating a significant contribution of Zn and Pb to high-PM_2.5 concentration. In addition, Zn and Pb exhibited the highest correlation coefficient among all other metallic elements of PM_2.5. A backward trajectory cluster analysis and CPF model were performed to examine the origin of PM_2.5. The high concentration of PM_2.5 was primarily influenced by emissions from industrial complexes located in the northeast and northwest areas.

• 한국대기환경학회지
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• 제31권2호
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• pp.97-104
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• 2015

The pollution of particulate matter (PM) is considered one of the hot socioenvironmental issues at present time. In this study, we investigated the distribution of fine particulate matter ($PM_{2.5}$) in Wangsimni commercial areas in Seoul, Korea to learn more about its environmental behavior in an urban area. Our analysis of $PM_{2.5}$ was made to distinguish the $PM_{2.5}$ pollution levels between three different types of site characteristics: (1) densely populated area, (2) thinly populated area, and (3) traffic roadside. Moreover, to assess the temporal trends in our study, the concentration levels of $PM_{2.5}$ were also compared between weekdays and weekends and between early in the afternoon and evening. The average concentration of $PM_{2.5}$ from densely and thinly populated areas were measured as $36.0{\pm}13.1$ and $32.3{\pm}11.2{\mu}g/m^3$, respectively. If the results are compared between different time bands, there were apparent differences between weekdays ($29.6{\pm}10.8{\mu}g/m^3$) and weekends ($36.9{\pm}12.1{\mu}g/m^3$). Such difference was also evident between noon ($27.8{\pm}5.8{\mu}g/m^3$) and evening ($38.3{\pm}13.7{\mu}g/m^3$). According to our research, concentration of $PM_{2.5}$ in the study area was affected more sensitively by time zone rather than the population density. The measurement data was also analyzed by drawing concentration map of $PM_{2.5}$ in the Wangsimni commercial areas based on data contouring method.

• 한국대기환경학회지
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• 제22권6호
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• pp.863-875
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• 2006

Intensive visibility monitoring was conducted to investigate physical and chemical characteristics of visibility impairment by airborne pollen. Light attenuation coefficients were optically measured by a transmissometer, a nephelometer, and an aethalometer. Elemental, ionic, and carbonaceous species were chemically analyzed on the filters collected by $PM_{2.5}$ and $PM_{10}$ samplers. Aerosol size distribution was analyzed using a cascade impactor during airborne pollen period. Airborne pollen count was calculated using a scanning electron microscope. Airborne pollen was emitted into the atmosphere in springtime and funker degraded visibility through its scattering and absorbing the light. Average light extinction coefficient was measured to be $211{\pm}36Mm^{-1}$ when airborne pollen was not observed. But it increased to $459{\pm}267Mm^{-1}$ during the airborne pollen period due to increase of average $PM_{2.5}$ and $PM_{10}$ mass concentration and relative humidity and airborne pollen count concentration for $PM_{10}$, which were measured to be $46.5{\pm}29.1{\mu}g\;m^{-3},\;97.0{\pm}41.7{\mu}g\;m^{-3},\;54.1{\pm}11.6%$, and $68.2{\pm}89.7m^{-3}$, respectively. Average light extinction efficiencies for $PM_{2.5}$ and $PM_{10}$ were calculated to be $5.9{\pm}0.9$ and $4.5{\pm}0.8m^2 g^{-1}$ during the airborne pollen period. Light extinction efficiency for $PM_{10}$ increased further than that for $PM_{2.5}$. The average light extinction budget by airborne pollen was estimated to be about 24% out of the average measured light extinction coefficient during the airborne pollen period.

• 한국환경과학회지
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• 제28권7호
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• pp.581-594
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• 2019

This research investigated the characteristics of $PM_{10}$ and $PM_{2.5}$ concentrations at the main subway stations in Busan. Annual mean $PM_{10}$ concentrations at the Seomyeon 1- waiting room and platform were $51.3{\mu}g/m^3$ and $47.5{\mu}g/m^3$, respectively, and the annual $PM_{2.5}$ concentration at the Seomyeon 1- platform was $28.8{\mu}g/m^3$. $PM_{2.5}$/$PM_{10}$ ratio at Seomyeon 1-platform and Dongnae station were 0.58 and 0.53, respectively. Diurnal variation of $PM_{10}$ concentration at subway stations in Busan was categorized into four types, depending on the number of peaks and the times at which the peaks occurred. Unlike the areas outside of the subway stations which reported maximum $PM_{10}$ concentration mostly in spring across the entire locations, the interiors of the subway stations reported the maximum $PM_{10}$ concentration in spring, winter, and even summer, depending on their location. $PM_{10}$ concentration was highest on Saturday and lowest on Sunday. The numbers of days when $PM_{10}$ concentration exceeded $100{\mu}g/m^3$ and $80{\mu}g/m^3$ per day over the last three years at the subway stations in Busan were 36 and 239, respectively. The findings of this research are expected to enhace the understanding of the fine particle characteristics at subway stations in Busan and be useful for developing a strategy for controlling urban indoor air quality.

• 한국환경과학회지
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• 제31권12호
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• pp.999-1012
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• 2022

To investigate the reason for the spatial difference in PM_2.5 (Particulate Matter, < 2.5 ㎛) concentration despite a similar synoptic pattern, a synoptic analysis was performed. The data used for this study were the daily average PM_2.5 concentration and meteorological data observed from 2016 to 2020 in Busan and Seoul metropolitan areas. Synoptic pressure patterns associated with high PM_2.5 concentration episodes (greater than 35 ㎍/m³) were analyzed using K-means cluster analysis, based on the 900 hPa geopotential height of NCEP (National Centers for Environmental Prediction) FNL (Final analysis) data. The analysis identified three sub-groups related to high concentrations occurring only in Busan and Seoul metropolitan areas. Although the synoptic patterns of high PM_2.5 concentration episodes that occur independently in Busan and Seoul metropolitan areas were similar, there was a difference in the intensity of pressure gradient and its direction, which tends to be an important factor determining the movement time of pollutants. The spatial difference in PM_2.5 concentration in the Korean Peninsula is due to the difference and direction of the atmospheric pressure gradient that develops from southwest to northeast direction.

• 한국수정란이식학회지
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• 제25권1호
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• pp.15-20
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• 2010

본 연구에서는 OPU를 통한 체내 유래 난자를 이용한 수정란 생산 시 1개월에서 6개월까지의 연구 기간에 따른 난포 생성수, 난자 회수율, 난자 등급율, 배반포 생성률을 분석하여 공란우의 활용 기간에 관하여 조사하였다. 1. 채란 기간에 따른 난포 생성수는 1개월에서 5개월까지의 난포 생성수는 $7.78{\pm}0.57$, $9{\pm}0.68$, $6.96{\pm}0.60$, $7.18{\pm}0.83$, $6.19{\pm}0.82$개로 유의적인 차이가 없었으나, 6개월째에는$2.83{\pm}0.39$개로 급격하게 줄어든 것을 알 수 있었다. 2. 채란 기간에 따른 난자 회수개수는 1개월에서 3개월까지는 $6.0{\pm}0.5$, $6.2{\pm}0.7$, $5.2{\pm}0.6$개로 유의적인 차이가 없었으나, 4개월부터 6개월까지 $3.7{\pm}0.5$, $2.8{\pm}0.4$, $1.2{\pm}0.2$개로 유의적으로 적어지는 것을 알 수 있었다. 난자 회수율 또한 1개월에서 3개월까지는 76.9%, 69.3%, 75.2%로 유의적인 차이가 없었으나, 4개월에서 6개월까지는 51.1%, 44.6%, 41.2%로 유의적으로 낮아지는 것을 알 수 있었다. 3. 채란 기간에 따른 난자 등급은 Grade 1, 2등급 출현율이 1개월부터 3개월까지 Grade 1은$1.8{\pm}0.3$, $2.2{\pm}0.3$, $1.9{\pm}0.3$, Grade 2는 $2.1{\pm}0.3$, $2.4{\pm}0.3$, $2.1{\pm}0.3$로 유의적으로 차이가 없었으나, 4개월, 5개월에는 Grade 1은 $1.73{\pm}0.27$, $1.14{\pm}0.33$, Grade 2는 $1.33{\pm}0.28$, $0.67{\pm}0.16$로 유의적으로 줄어들었으며, 6개월에는 Grade 1은 $0.3{\pm}0.1$, Grade 2는 $0.5{\pm}0.2$로 현저히 줄어든 것을 알 수 있었다. Grade 3과 4의 출현율은 유의적으로 차이가 없었다. 4. 채란 기간에 따른 배반포 발달율은 1개월에서 3개월까지의 배반포 발달율은 37.2%, 40.4%, 44.6%로 높은 발달율을 보이며 차이가 없었으나, 4개월째에는 24.8%, 5개월째에는 29.3%, 6개월째에는 28.6%로 급격하게 줄어드는 것을 알 수 있었다. 1회 채란 시 수정란의 생산 개수 또한 1개월에서 3개월까지는 $2.2{\pm}0.3$, $2.5{\pm}0.3$, $2.3{\pm}0.4$개로 유의적인 차이가 없었으나, 4개월째부터 6개월까지는 $0.9{\pm}0.2$, $0.8{\pm}0.2$, $0.3{\pm}0.2$개로 현저히 줄어드는 것을 알 수 있었다. 이상의 결과에서 약 3개월까지는 공란우의 활용이 효율적인 점과 4개월부터는 난자 회수와 그에 따른 1회 채란 시 배반포의 생성 수 또한 점차 적으로 줄어드는 것을 알 수 있었다. 따라서, 공란우의 활용을 최대 3개월까지 활용하고, 교체한다면 3~4일 간격으로 1주일에 2회 OPU 방법으로 체내 난자를 채란 후 수정란을 생산하는 시스템은 1두에 3개월간 약 48개의 이식 가능한 수정란을 생산할 수 있고, 산술적으로 년간 1두당 약 200개의 이식 가능한 OPU 유래 수정란을 생산할 수 있을 것이다. 따라서 공란우를 3개월 활용 후 교체를 하는 것이 경제적이며 효율적인 방법이라고 사료된다.

• 한국식품과학회지
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• 제28권1호
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• pp.157-161
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• 1996

우리나라 고유의 전통 조미식품인 고추장의 품질개선과 담금 방법을 과학적으로 표준화하기 위하여 전국의 각 가정에서 담은 55점의 전통 고추장을 수집하여 미생물상과 이화학적 특성을 조사하였다. 전통 고추장의 평균 성분조성은 수분 $46.71{\pm}5.98%$, 총당 $46.87{\pm}8.83%$, 조단백질 $11.77{\pm}3.90%$, 식염 $15.01{\pm}6.48%$, 환원당 $27.52{\pm}7.32%$, 아미노태 질소 $0.26{\pm}0.15%$, 에탄올 $2.69{\pm}2.35%$이었고, pH는 $4.60{\pm}0.23$, 적정산도 $27.26{\pm}10.98\;ml/10\;g$이었다. 전통고추장의 수분활성도는 $0.79{\pm}0.04$, 색도는 L값이 $16.03{\pm}2.89$, a값이 $20.42{\pm}4.37$, b값이 $9.71{\pm}1.92$이었다. 고추장 중의 호기성 세균과 혐기성 세균, 효모수는 각각 $1.02{\times}10^8{\pm}1.29{\times}10^8\;CFU/g$과 $2.24{\times}10^7{\pm}3.90{\times}10^7\;CFU/g$, $5.90{\times}10^5{\pm}2.25{\times}10^6\;CFU/g$이었다. 고추장 중에는 상당한 액화 및 당화효소 그리고 단백질 분해효소의 활성이 확인되었다.

• 한국환경과학회지
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• 제26권1호
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• pp.29-36
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• 2017

Aerosol mass size distributions were investigated at 865 m high the of Jirisan national park. A nanosampler cascade impactor was used to collect aerosols. The atmospheric aerosol particles had a unimodal mass size distribution, which peaked at $0.5-1.0{\mu}m$, and a mass aerodynamic diameter of $1.13{\mu}m$. The annual average concentrations of TSP, $PM_{10}$, $PM_{2.5}$, $PM_1$, $PM_{0.5}$ and $PM_{0.1}$ were $20.9{\mu}g/m^3$, $19.3{\mu}g/m^3$, $14.9{\mu}g/m^3$, $10.7{\mu}g/m^3$, $5.3{\mu}g/m^3$, $1.2{\mu}g/m^3$, respectively. TSP concentrations were below $30{\mu}g/m^3$ during the sampling period. On average $PM_{10}$, $PM_{2.5}$, $PM_1$, $PM_{0.5}$ and $PM_{0.1}$ made up 0.91, 0.70, 0.41, 0.19 and 0.07 of TSP, respectively. The annual average of PM2.5/PM10 ratio was 0.77.

• 대한핵의학회지
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• 제17권2호
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• pp.1-17
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• 1983

The purpose of this study is to investigate the effects of thyroid hormone on the left ventricular(LV) volume arid function in man with untreated hyperthyroidism and to determine the effects of successful therapy for thyrotoxicosis on the ventricular pathophysiology. In the present study, equilibrium radionuclide cardiac angiography was performed and LV volume index, ejection phase indexes of LV performance, serum thyroid hormone levels and other hemodynamic parameters were measured in 28 normal subjects and 39 patients with hyperthyroidism before treatment and again every 4 weeks for the first 2 months after the initiation of effective therapy. The results obtained were as follows; 1) In the untreated hyperthyroid state heart rate, blood volume, cardiac index and stroke volume index($97{\pm}14$ beats/min, $73.5{\pm}11.8ml/kg,\;6.9{\pm}1.4\;l/min/m^2$ and $77.6{\pm}13.8ml/m^2$, respectively) were increased significantly compared to those in normal control($74{\pm}12beats/min$, $66.6{\pm}14.8ml/kg,\;3.8{\pm}1.2\;l/min/m^2$ and $56.6{\pm}13.2ml/m^2$ respectively). $(Mean{\pm}SD)$ 2) There was a significant increase in LV end-diastolic volume index in patients with hyperthyroidism ($30.5{\pm}7.5$ for hyperthyroid group compared to a normal control of $22.2{\pm}6.5$; p<0.001), whereas end-systolic volume index remained unchanged $9.6{\pm}3.6\;and\;8.8{\pm}3.3$ respectively).3) In patients with hyperthyroidism, LV ejection fraction was $70.0{\pm}5.6%$, fractional shortening $32.9{\pm}5.1%$, mean velocity of circumferential fiber shortening(mean Vcf) $1.34{\pm}0.31$ circ/sec and maximum ejection rate $3.47{\pm}0.80$. All the ejection phase indexes were significantly greater than those in normal control($65.2{\pm}5.7%,\;28.8{\pm}3.2%,\;0.88{\pm}0.37$ circ/see and $2.27{\pm}0.50$, respectively; p<0.001). 4) Effective therapy produced significant decrease in all the values of serum thyroid hormone concentrations(p<0.00l), hemodynamic parameters(p<0.001), end-diastolic volume index(p<0.01) and ejection phase indexes of LV contractility in patients with hyperthyroidism and after one to two months, when the patients were euthyroid, these measurements were in the range of normal. 5) A significant linear correlation between mean Vcf and serum thyroxine level(r=0.63, p<0.001) as well as between mean Vcf and serum triiodothyronine level(r=0.62, p<0.001) was found. The lesser degree of correlation was also noted between other ejection phase indexes and serum thyroid hormone concentrations. The results indicate that the major effects of excess thyroid hormone on the LV in human beings with hyperthyroidism are an enhancement of LV function and an increase in LV enddiastolic volume and that these effects cause predictable reversible cardiac alteration which are changed dramatically and immediately after effective therapy.