• Asian Journal of Atmospheric Environment
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• 제5권4호
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• pp.237-246
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• 2011

To explore the sources of carbonaceous material in the airborne particulate matter (PM), comprehensive PM sampling was performed (3 to 14 January 2010) at a traffic hot spot site (HS), Farm Gate, Dhaka using several samplers: AirMetrics MiniVol (for $PM_{10}$ and $PM_{2.5}$) and MOUDI (for size fractionated submicron PM). Long-term PM data (April 2000 to March 2006 and April 2000 to March 2010 in two size fractions ($PM_{2.2}$ and $PM_{2.2-10}$) obtained from two air quality-monitoring stations, one at Farm Gate (HS) and another at a semi-residential (SR) area (Atomic Energy Centre, Dhaka Campus, (AECD)), respectively were also analyzed. The long-term PM trend shows that fine particulate matter concentrations have decreased over time as a result of government policy interventions even with increasing vehicles on the road. The ratio of $PM_{2.5}/PM_{10}$ showed that the average $PM_{2.5}$ mass was about 78% of the $PM_{10}$ mass. It was also found that about 63% of $PM_{2.5}$ mass is $PM_1$. The total contribution of BC to $PM_{2.5}$ is about 16% and showed a decreasing trend over the years. It was observed that $PM_1$ fractions contained the major amount of carbonaceous materials, which mainly originated from high temperature combustion process in the $PM_{2.5}$. From the IMPROVE TOR protocol carbon fraction analysis, it was observed that emissions from gasoline vehicles contributed to $PM_1$ given the high abundance of EC1 and OC2 and the contribution of diesel to $PM_1$ is minimal as indicated by the low abundance of OC1 and EC2. Source apportionment results also show that vehicular exhaust is the largest contributors to PM in Dhaka. There is also transported $PM_{2.2}$from regional sources. With the increasing economic activities and recent GDP growth, the number of vehicles and brick kilns has significantly increased in and around Dhaka. Further action will be required to further reduce PM-related air pollution in Dhaka.

• 한국응용곤충학회지
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• 제34권4호
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• pp.300-307
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• 1995

치자나무의 실생묘포장에서 잎을 식해하는줄녹색박각시의 생활사를 1984년부터 1985년까지 남해에서 조사한 결과를 요약하면 다음과 같다. 줄녹색박각시의 산란기간은 5월 하순부터 26일간이었고, 평균 20.4개의 알을 기주 식물의 잎 뒷면에 산란하였다. 산란후 14일부터 16일 사이에 부화하고, 부화율은 97.6%였다. 알은 타원형이고, 크기는 지름이 1.01mm 길이가 1.14 mm이고 난기간은 14.6일이다. 유충의 평균 길이는 1령이 $3.52\pm$1.01 mm, 2령이 $6.46\pm$0.45mm, 3령이 $13.19\pm$4.27mm, 4령이 $24.08\pm$2.22mm, 5령이 $43.71\pm$5.62 mm이고, 유충의 평균체중은 1령이 $13.34\pm$2.41mg, 2령이 $29.83\pm$6.88mg, 3령이 $76.64\pm$31.31mg, 4령이 $292.09\pm$107.70mg, 5령이 $2,144.84\pm$760.70mg이다. 유충기간은 7월부터 10월까지로 1령이, 12일, 2령이 36일, 3령이 32일, 4령이 16일, 5령이 20일로 총유충기간은 116일이었고, 유충기간 동안에 1마리의 유충이 실생묘 17.18주를 가해하였다. 제5령 유웅이 종령유충으로 평균 15 mm 땅속에 들어가 토립으로 집을 짓고, 그 속에서 번데기가 되어 월동하며, 번데기의 평균 길이는 33.6mm이고, 평균 체중은 2,032mg이다. 성충은 이듬해 5월 중순에서 하순까지 우화하는데, 성충의 성비는 암컷이 42.82%이고, 체색형의 비는 갈색형이 89.93%였다.

• 대한원격탐사학회지
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• 제36권6_3호
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• pp.1691-1710
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• 2020

본 연구에서는 평택과 부산의 초등학교를 대상으로 학교 주변과 교실 내를 포함하여 총 16개 지점에서 PM2.5(particulate matter less than 2.5 ㎛ in diameter) 및 PM10(particulate matter less than 10 ㎛ in diameter)을 동시에 측정하였고, 이 결과를 여러 국외 선행연구 리뷰를 통해서 획득한 실내·외 PM2.5 및 PM10 측정 농도 및 I/O ratio(Indoor/Outdoor ratio)와 비교하였다. 선행연구는 총 30건의 연구에서 144건의 사례를 수집하여 이를 실내활동, 측정 계절, 건물용도, 주변환경에 대해 다양한 항목별로 분류하여 본 연구의 측정결과와 비교하였다. 선행연구 결과에서 PM2.5는 흡연활동이나 요리활동 등의 실내 연소작용이 없는 환경에서는 외기농도가 실내농도에 중요한 영향을 미치는 반면, PM10은 외기농도와 함께 물리적 활동에 따른 재 비산이 중요한 실내 배출원일 것으로 보인다. 평택과 부산의 초등학교에서의 측정결과도 선행연구 리뷰 결론을 뒷받침하는 양상을 보였고, 공기청정기 사용이 미세먼지 저감에 효율적인 것으로 나타났다. PM2.5와 PM10은 실내 배출원 및 외기와의 상호작용 영향이 다를 수 있으며 환기방식에서는 강제환기가 자연환기보다 PM2.5와 PM10의 실내농도 감소에 더 효율적일 수 있는 것으로 보인다.

• Journal of Chest Surgery
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• 제33권7호
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• pp.552-559
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• 2000

배경; Carbomedics 기계판막은 보편적으로 많이 이용되는 기계판막의 일종이며 국립의료원에서는 1988년부터 이것을 사용하여 왔다. 저자들은 1994년에 중단기 성적을 흉부외과 학회지에 보고한바 있으며 이번에 10년 임상성적을 보고하고자 한다. 대상 및 방법 ; 1988년 8월부터 1998년 12월 RK지 Crbomedics 판막을 이용하여 판막치환술을 받은 235명의 연속적인 환자를 대상으로 하였으며 승모판막 치환 143예, 승모판막 및 대동맥판막치환 59예, 대동맥 판막치환 33예이었다. 평균 연령은 40세 이었으며 남녀의 성비는 85;150으로 여성환자가 원등하게 많았다. 임상추적 종료시점은 1999년 6월로 정했으며 추적율은 9704% 이었다. 전체 추적 기간은 1209.2환자-년이었고 평균 5.7년이었다. 결과; 조기 사망류은 8.9%, 만기 사망률은 4.7%로 전체사망율은 13.1%(31명/235명)이었다. 10년 생존율은 95.2$\pm$1.6%이었다. (승모판막치환; 94.9$\pm$2.1%, 승모판막 및 대동맥판막치환; 95.0$\pm$3.7%, 대동맥판막치환; 96.2$\pm$3.8%). 판막관련 합병증 중 혈전전색증, 판막혈전폐쇄증, 항응고제 관련 출혈, 판막주위 누출, 심내막염등의 linearized incidencesns 각각 환자-년당 0.59%, 0.5%, 0.25%, 0.17%, 0.17%였으며 혈전전색증이 없을 확률은 96.2$\pm$1.5%, 판막폐쇄증이 없을 확률은 96.7$\pm$1.4%, 항응고제관련 출혈이 없을 확률은 98.7$\pm$1.0%이었고 전체 판막관련 합병증이 없을 확률은 88.9$\pm$2.5%이었다. 결론; 장기 추적검사에서 Carbomedics 판막은 판막과 관련된 합병증 및 사망률이 낮았다.

• 한국환경보건학회지
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• 제50권1호
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• pp.16-24
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• 2024

Background: Indoor PM_2.5 concentrations in residential houses can be affected by various factors depending on the season. This is because not only do the climate characteristics depend on the season, but the activity patterns of occupants are also different. Objectives: The purpose of this study is to compare factors affecting indoor PM_2.5 concentrations in apartments and detached houses in Daegu according to seasonal changes. Methods: This study included 20 households in Daegu, South Korea. The study was conducted during the summer (from July 10 to August 10, 2023) and the autumn (from September 11 to October 9, 2023). A sensor-based instrument for PM_2.5 levels was installed in the living room of each residence, and measurements were taken continuously for 24 hours at intervals of one minute during the measurement period. Based on the air quality monitoring system data in Daegu, outdoor PM_2.5 concentrations were estimated using ordinary kriging (OK) in Python. In addition, the indoor activities of the occupants were investigated using a time-activity pattern diary. The affecting factors of indoor PM_2.5 concentration were analyzed using multiple regression analysis. Results: Indoor and outdoor PM_2.5 concentrations of the residences during summer were 15.27±11.09 ㎍/m³ and 11.52±7.56 ㎍/m³, respectively. Indoor and outdoor PM_2.5 concentrations during autumn were 13.82±9.61 ㎍/m³ and 9.57±5.50 ㎍/m³, respectively. The PM_2.5 concentrations were higher in summer compared to autumn both indoors and outdoors. The primary factor affecting indoor PM_2.5 concentration in summer was occupant activity. On the other hand, during the autumn season, the primary affecting factor was outdoor PM_2.5 concentration. Conclusions: Indoor PM_2.5 concentration in residential houses is affected by occupant activity such as the inflow of outdoor PM_2.5 concentration, cooking, and cleaning, as found in previous studies. However, it was revealed that there were differences depending on the season.

• 디지털융복합연구
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• 제14권12호
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• pp.369-375
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• 2016

본 연구는 환자의 경추보호대 착용 여부에 따른 후두마스크기도기(LMA)와 I-gel, Streamlined Liner of the Pharynx Airway(SLIPA) 등 3가지 성문위기구의 삽관 용이성을 비교하기 위해 시행되었다. 응급의료현장에서 활동 중인 119 구급대원 39명에게 3가지 성문위기구에 대한 짧은 교육을 시행한 후 삽관시간과 삽관시도횟수를 측정하였다. 삽관시간은 중립위와 경추보호대 착용 시 모두 I-gel($10.5{\pm}2.2$, $11.4{\pm}5.7$), SLIPA($12.3 {\pm}5.1$, $12.0{\pm}6.8$), LMA($17.2{\pm}3.2$, $18.5{\pm}5.5$) 순으로 빨랐다 (p<0.05). 각 기도기별 중립위와 경추보호대 착용 시 삽관시간의 차이는 없었다. 결론적으로 I-gel과 SLIPA가 LMA보다 중립위와 경추보호대 착용 시 모두에서 삽관시간이 더 빠른 결과를 보였다.

• Reproductive and Developmental Biology
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• 제35권4호
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• pp.475-478
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• 2011

In the present study, the effect of cysteine and NT or bisphenol A(BP) on in vitro aturation(IVM) of porcine oocytes were examined. COCs was cultured in NCSU-23 medium supplement with 10% FCS which had previously been covered with mineral oil and equilibrated in a humidified atmosphere of 5% $CO_2$ and 95% air at $38^{\circ}C$. The IVM rate of oocytes cultured for 48 hrs in NCSU-23 medium supplement with 0.5~10.0 mM cysteine were $34.0{\pm}3.2%$, $36.0{\pm}3.5%$, $48.0{\pm}3.8%$, $22.0{\pm}3.2%$, respectively. The IVM rate of oocytes cultured in NCSU-23 medium supplement with 0.5~5.0mM NT for 48 hrs were $24.0{\pm}4.2%$, $18.0{\pm}4.9%$, $8.0{\pm}2.2%$, respectively. NT affects oocyte in vitro maturation rate in a dose-dependent. This result were significantly lower than the control group. The IVM rate of oocytes cultured for 48 hrs in NCSU-23 medium supplement with 1.0 mM NT+5.0 mM cysteine($38.0{\pm}4.3%$) were significantly higher than that of NT treatment. The IVM rate of oocytes cultured in NCSU-23 medium supplement with 0.05~5.0 mM BP for 48 hrs were $20.0{\pm}4.7%$, $10.0{\pm}5.3%$, $6.0{\pm}3.2%$, respectively. The IVM rate of oocytes cultured in NCSU-23 medium supplement with BP was significantly lower cultured non supplement of BP ($44.0{\pm}3.5%$). BP affects porcine oocyte maturation rate in a dose-dependent manner. The IVM rate of oocytes cultured for 48 hrs in NCSU-23 medium supplement with 1.0 mM BP+5.0 mM cycteine ($32.0{\pm}3.2%$) were increased than that of BP treatment.

• 한국산업보건학회지
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• 제23권4호
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• pp.356-366
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• 2013

Objectives: This study was conducted in order to evaluate $PM_{2.5}$ concentrations at 20 offices connected to the manufacturing industry from the beginning of September to the end of November 2012. Methods: A total of 20 samples were collected from 20 office buildings. Each $PM_{2.5}$ sample was collected by a 37 mm PTFE filter attached to a Personal Environment Monitor. Results: The geometric mean concentrations of $PM_{2.5}$ in the offices was $23.47{\mu}g/m^3$, and the mean $PM_{2.5}$ concentrations measured in smoking offices were much higher than those of measured in non-smoking offices($24.83{\mu}g/m^3$ and $21.55{\mu}g/m^3$, respectively). $PM_{2.5}$ was revealed to be higher in small offices($39.52{\mu}g/m^3$) than in medium or large offices($22.69{\mu}g/m^3$ and $11.04{\mu}g/m^3$, respectively). The mean $PM_{2.5}$ concentration of offices located on the 1st floor was higher than that of those on the 2nd floor, and those of offices located in the workplace were higher than those out of the workplace. The multiple regression model showed that concentration of $PM_{2.5}$ was positively associated with the method of ventilation. Conclusions: Smoking, ventilation method, location, and inflow of outdoor particulate matter are the most important factors for office $PM_{2.5}$ concentrations.

• 한국환경과학회지
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• 제26권4호
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• pp.447-456
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• 2017

Chemical properties of aerosols were investigated by analyzing the inorganic water-soluble content in $PM_{2.5}$ collected in the downtown area of Jeju City in Jeju Island. Due to an increase in both the number of visiting tourists and the size of local population, the number of cars in this area is increasing, causing an increase in $PM_{2.5}$. Eight $PM_{2.5}$-bound major inorganic ions were analyzed during the summer and winter periods. The water-soluble inorganic component represents a significant fraction of $PM_{2.5}$. In particular, secondary inorganic aerosols contribute 36.2% and 47.5% of $PM_{2.5}$ mass in summer and winter, respectively. Nitrate concentrations increase for $[NH_4{^+}]/[SO_4{^{2-}}]$>1.5, and excess ammonium, which is necessary for ammonium nitrate formation, is linearly correlated with nitrate. These results are clearly observed during the winter because conditions are more conducive to the formation of ammonium nitrate. A significant negative correlation between Nitrogen Oxidation Ratio (NOR) and temperature was observed. The obtained results can be useful for a better understanding of the aerosol dynamics in the downtown area in Jeju City.

• 한국수정란이식학회지
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• 제27권3호
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• pp.127-131
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• 2012

발정주기와 상관없이 CIDR을 삽입하는 날에 50 mg progesterone, 2.5 mg estradiol benzoate를 근육주사하였다. CIDR 삽입 후 4, 5일에 28 AU FSH (Antorin R10)을 4일 동안 감량법으로 주사하였다. 6, 7회 FSH 주사 후 25 mg, 15 mg $PGF_2{\alpha}$를 각각 주사한 다음, CIDR는 7회 FSH 주사 후 제거하였다. 1회째 $PGF_2{\alpha}$ 주사 후 48시간에 $200{\mu}g$ GnRH를 주사하였다. 공란우는 발정확인 후 12시간 간격으로 3회 인공수정을 실시하였으며, 수정란의 채란은 발정확인 후 7일째 회수하였다. 과배란 처리된 공란우에서 회수된 총 난자수, 이식가능 수정란, 퇴행란 및 미수정란은 각각 $11.6{\pm}7.9$, $5.5{\pm}4.4$, $3.0{\pm}3.3$ 및 $2.6{\pm}4.1$개였다. 1~2산의 공란우($8.9{\pm}1.9$)보다 3~5산의 공란우($14.3{\pm}1.3$)에서 총 난자수가 유의적으로 많았다(P<0.05). 회수된 정상 수정란 수도 3~5산의 공란우($7.3{\pm}0.8$)에서 6산 이상의 공란우($3.7{\pm}1.5$)보다 유의적으로 많았다(P<0.05). 회수된 총 난자수와 정상수정란도 각각 가을($10.1{\pm}1.8$, $4.5{\pm}1.1$)과 겨울($6.3{\pm}1.8$, $3.3{\pm}1.1$)보다 여름($16.4{\pm}2.3$, $8.1{\pm}1.4$)에 유의적으로 많았다(P<0.05). 이식가능 수정란은 겨울($3.0{\pm}1.0$)보다 여름($7.6{\pm}1.3$)에서 유의적으로 많이 회수하였다(P<0.05). 결론적으로 공란우의 산차, 과배란 처리계절은 한우수정란 생산에 영향을 미치는 것으로 나타났다.