• Asian Journal of Atmospheric Environment
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• v.5 no.4
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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.

• Korean journal of applied entomology
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• v.34 no.4
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• pp.300-307
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• 1995

This study was carried out to investigate the life cycle of Cephonodes hylas (Linne), that is damaging to Gardenia jasminoides Ellis in the seedbed at Namhae during 1984 and 1985. Results are summarized as follows. The eggs were laid in mass on the leaf surface of the host plants. The oviposition period lasts for 26 days after late-May. The average number of eggs and average hatching rate were 20.36 and 97.61% , respectively. It takes 14-16 days until hatching. The egg shape was oval which its size was 1.01 mm in diameter and 1.48 mm in length. The body length of each larval instar from the 1st to the 5th were $3.52\pm$1.01, $6.46\pm$0.45, $13.19\pm$4.27, $24.08\pm$2.22 and $43.71\pm$5.62 mm, respectively. The average weight of each larval instar were $13.34\pm$2.41, $29.83\pm$6.88, $76.64\pm$31.31, $292.09\pm$107.70 and 2,$144.84\pm$760.70 mm, respectively. The larval period was observed from July to October, and total duration of larval stage was 116 days in which duration of each larval instar from the 1st to the 5th were 12, 36, 32, 16 and 20 days, respectively. During larval stage, a larvae feed on 17~18 seedlings. The 5th instar larvae built its place in soil for overwinter and became pupa. The body length of pupa was 33.6 mm and average weight was 2,032 mg Adult was emerged from overwintened pupa from mid through late-May in the followings year. The sex ratio of female was 42.82% and the color ratio of brown was 89.93%.

• Korean Journal of Remote Sensing
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• v.36 no.6_3
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• pp.1691-1710
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• 2020

We measured PM2.5 and PM10 (particulate matter less than 2.5 ㎛ and 10 ㎛ in diameter, respectively) simultaneously at 16 locations around an elementary school and classrooms in Busan and Pyeongtaek, South Korea. In this study, we compared the results of this field intensive with those in the literature (144 cases of 30 studies), focusing on I/O (Indoor/Outdoor) ratios. We also reviewed the results of previous studies, categorizing them into related sub-categories for indoor-activities, seasons, building-uses, and the surrounding environment. We conclude that indoor PM10 is affected more by indoor-sources (e.g., physical activities) than PM2.5 in the absence of combustion sources like smoking and cooking. Additionally, PM10 and PM2.5 likely have different indoor-outdoor infiltration efficiencies. Conclusively, PM10 in classrooms can be more sensitively affected by both indoor activities and ambient concentrations, and mechanical ventilation can be more efficient in reducing PM concentrations than natural ventilation.

• Journal of Chest Surgery
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• v.33 no.7
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• pp.552-559
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• 2000

Background; The aim of this study is to evaluate our clinical experience with the Carbomedics heart valve prosthesis. Material and Method; Between Aug. 1988 and Dec. 1998, 294 Carbomidics valves were implanted in 235 patients(mitral; 143, mitral and aortic; 59, aortic; 33) The mean age at operation is 40.0$\pm$12.3 years(range 7 to 68 years); 63.8% (150patients) were woman. Follow up was 97.4% complete and mean follow up time was 5.7years with a total of 1209.2 patient-years. Result; The hospital mortality was 8.9%(mitral; was 95.2$\pm$1.6%(mitral ; 94.9$\pm$2.1%, mitral and aortic 95.0$\pm$3.7%, aortic 96.2$\pm$3.8%). Actual freedom rates from complications(linearized rates in parentheses) were fllowings; thromboembolism 96.2$\pm$1.5%(0.59%pt-yr), valve thrombosis 96.7$\pm$1.4%(0.5%/pt/yr), anticoagulant related hemorrhage 98.3$\pm$1.0%(0.25%/pt-yr), perivalvular leak 99.0$\pm$1.4%(0.5%/pt-yr), endocarditis 98.7$\pm$1.0%(0.25%/pt-yr), perivalvular leak 99.0$\pm$0.7%(0.17%pt-yr), endocarditis 98.7$\pm$1.0%(0.17%$\pm$pt-yr) and overall valve-related complications 88.9$\pm$2.5%(1.68%/pt-yr). Conclusion; The clinical performance of the Carbomedics valve was quite satisfactory with a low incidence of valve related mortality and morbidity.

• Journal of Environmental Health Sciences
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• v.50 no.1
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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.

• Reproductive and Developmental Biology
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• v.35 no.4
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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.

• Journal of Digital Convergence
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• v.14 no.12
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• pp.369-375
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• 2016

Purpose of this study was to compare the easiness of insertion of three Supraglottic airway devices(SADs) in a neutral and cervical neck collar position in a manikin setting. Three different SADs-Laryngeal Mask Classic (LMA), I-gel and Streamlined Liner of the Pharynx Airway(SLIPA) were applied. Thirty nine emergency medical technicians (EMTs) who are working in Korea 119 rescue services were taught briefly about the use of the LMA, I-gel and SLIPA in a manikin setting. The time to effective ventilation was shorter in I-gel ($10.5{\pm}2.2$, $11.4{\pm}5.7$) and SLIPA ($12.3 {\pm}5.1$, $12.0{\pm}6.8$) than LMA ($17.2{\pm}3.2$, $18.5{\pm}5.5$) in a neutral and cervical neck collar position, respectively(p<0.05). There was no difference between head positions in each of the airways. In conclusion, in the speed of insertion, I-gel and SLIPA were superior to LMA in the neutral and cervical collar setting of a manikin.

• Journal of Embryo Transfer
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• v.27 no.3
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• pp.127-131
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• 2012

This study was performed to investigate the effects of parity and season on the embryo production in superovulated Hanwoo cows. Superovulation was performed from 1 to 8 times by repeated superovulation treatment of Hanwoo cows (n = 22). Irrespective of estrous cycle, donor cows were received a CIDR, progesterone (50 mg) and estradiol benzoate (2.5 mg). After 4.5 days, the donor cows were superovulated with total 28AU FSH (Antorin R-10) administrated twice daily in a decreasing dose for 4 days. On $6^{th}$ and $7^{th}$ of FSH injection, 2.5 mg and 15 mg $PGF_2{\alpha}$ were injected i.m, respectively. CIDR was removed at the $7^{th}$ FSH injection. The donor cows received $200{\mu}g$GnRH at 48 hrs after $1^{st}$ $PGF_2{\alpha}$ injection. The donor cows were artificially inseminated three times after estrous detection at 12 hr intervals and embryos were recovered 7 days after estrous detection. The mean number of total ova, transferrable embryos, degenerated embryos and unfertilized oocytes were $11.6{\pm}7.9$, $5.5{\pm}4.4$, $3.0{\pm}3.3$ and $2.6{\pm}4.1$ per donor cows, respectively. A higher number of total ova were recovered in parity 3~5 ($14.3{\pm}1.3$) than 1~2 ($8.9{\pm}1.9$, P<0.05). The number of recovered normal embryos is significantly higher in parity 3~5 ($7.3{\pm}0.8$) than that of over 6 ($3.7{\pm}1.5$). Significantly higher number of total ova and normal embryos were recovered in summer ($16.4{\pm}2.3$, $8.1{\pm}1.4$) than in autumn ($10.1{\pm}1.8$, $4.5{\pm}1.1$) and winter ($6.3{\pm}1.8$, $3.3{\pm}1.1$), respectively (P<0.05). Transferable embryos were significantly higher in summer ($7.6{\pm}1.3$) than in winter ($3.0{\pm}1.0$, P< 0.05). The results were showed that parity and season affecting on the production of embryos in superovulated Hanwoo.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.4
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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.

• Journal of Environmental Science International
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• v.26 no.4
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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.