• Title/Summary/Keyword: PM-2.5

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Clinical Features of Enuresis in Children with Diabetes Mellitus (소아 당뇨병 환아에서 야뇨증의 임상적 특징)

  • Kim, Myoung-Uk;Kim, Sae-Yoon;Choi, Jung-Youn;Cho, Min-Hyun;Ko, Cheol-Woo;Kim, Heung-Sik;Park, Yong-Hoon
    • Childhood Kidney Diseases
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    • v.14 no.2
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    • pp.210-217
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    • 2010
  • Purpose : Diabetes mellitus (DM) is known as one of the common causes of secondary enuresis in children. However, enuresis in diabetic children is overlooked only as a symptom of polyuria due to hyperglycemia. We evaluated the prevalence of nocturnal enuresis in children with diabetes mellitus in this paper. Methods : Among children with diabetes in three hospitals in Daegu area, 117 agreed to 'Tele research by means of a questionnaire'. Results : Diabetic patients were divided into two groups: Nocturnal enuresis and nonnocturnal enuresis group. thirty-two of 117 (27.0%) patients were in enuresis group, with more daytime urination than non-nocturnal enuresis group ($4.2{\pm}1.6/3.6{\pm}1.2$ times, P=0.016). HbA1c at diagnosis was $12.0{\pm}2.3%/12.0{\pm}2.5%$, and at follow-up $9.3{\pm}2.3%/8.3{\pm}2.3%$ (P =0.042). Insulin was administered at $1.1{\pm}0.5/1.1{\pm}0.4$ units/kg/day. Ten children of enuresis (31.2%) group were monosymptomatic (MNE) and 22 (68.8%) children were non-monosymptomatic enuresis (non-MNE). Fourteen (43.8%) of enuresis group had persistent symptoms, with 5 MNE and 9 non-MNE each. HbA1c at diagnosis was $11.1{\pm}2.5$, $12.4{\pm}2.1$, higher in non-MNE (P=0.144). Average arousal during sleep was step $3.3{\pm}1.2$, $2.5{\pm}1.0$, higher in improved enuresis group (P=0.059). Conclusion : Nocturnal enuresis among DM patients is underestimated. However, considering psychological and social effects of enuresis in children, extensive and long-term studies are needed in the future to clarify relationship between prevalence and DM control.

Studies on Blood Gas Values in Non-Human Primates Reared in Korea (國內詞育 원숭이의 血液가스値에 관한 硏究)

  • 윤상보;김덕환;서지민;신남식;현병화;박배근;송희종
    • Journal of Veterinary Clinics
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    • v.18 no.4
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    • pp.397-401
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    • 2001
  • Blood gas values such as pO$_2$ were studied in common marmosets, crab-eating macaques and Japanese macaques, rhesus macaques and celebes macaque reared in Korea. Blood pH and blood gas values were evaluated in both arterial and venous blood. pH, p$CO_2$, and pO$_2$, of arterial blood in common marmosets were measured as 7.4$\pm$0.1, 29.2$\pm$3.6 mmHg and 81.5$\pm$8.9 mmHg, respectively. Corresponding values in one crab-eating macaque were 7.3, 41.3 mmHg and 46.5 mmHg, respectively. In case of venous blood, pH, p$CO_2$, and pO$_2$, in common marmosets were observed as 7.2$\pm$0.2, 64.9$\pm$18.3 mmHg and 23.5$\pm$5.4 mmHg, respectively. On the while, pH, p$CO_2$, and pO$_2$, of venous blood in crab-eating macaques showed 7.2$\pm$0.2, 49.9$\pm$8.0 mmHg and 38.3$\pm$8.8 mmHg, respectively. Venous pH, p$CO_2$, and pO$_2$, in Japanese macaques were 7.1$\pm$0.2, 56.4$\pm$5.3 mmHg and 40.1$\pm$9.3 mmHg, respectively. Those values in one rhesus macaque were 7.2, 61.1 mmHg and 24.9 mmHg, and in celebes macaque were 7.1, 54.3 mmHg and 31.8 mmHg, respectively.

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Estimation of Particulate Matter Emission Factors from Open Burning (노천소각에서 배출되는 먼지 배출계수 산정에 관한 연구)

  • Jung, No-El;Jo, Myeong-Ran;Heo, Sun-Hwa;Kim, Hyung-Chun;Park, Jung-Min;Lee, Dae-Gyun;Hong, Ji-Hyung;Lee, Suk-Jo;Lee, Yeong-Jae
    • Journal of Korean Society for Atmospheric Environment
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    • v.28 no.3
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    • pp.348-356
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    • 2012
  • It is very important to investigate air pollutants and emissions emitted from open burning in order to control nonpoint sources effectively. In this study, we utilized incineration simulator proposed by U.S. EPA and investigated concentrations of TSP, PM10, PM2.5 from woods and household wastes burning to calculate emission factors and build emission inventories. The results of experiment with 15 kg of woods and 3 kg of household wastes using the incineration simulator were as follows: in case of woods burning, TSP concentration was $66.4mg/m^3$, PM10 concentration was $28.4mg/m^3$, PM2.5 concentration was $17.9mg/m^3$, respectively; in case of household wastes burning, TSP concentration was $118.4mg/m^3$, PM10 concentration was $66.8mg/m^3$, PM2.5 concentration was $55.2mg/m^3$, respectively. Concentrations from household burning, as stated above, were higher than those from woods burning. Emission factors (EFs) for woods and household wastes burning were calculated as 2.45 and 6.75 g/kg for TSP, 0.86 and 5.45 g/kg for PM10, 0.78 and 4.81 g/kg for PM2.5, respectively. EFs of TSP, PM10, PM2.5 calculated from household wastes burning were higher than those of woods burning. When we added PM emissions from woods burning and household wastes burning to Korean National Emission Inventory named as Clean Air Policy Support System (CAPSS), CAPSS annual emissions of TSP, PM10, PM2.5 were increased by 0.08~0.26% (An increase rate for TSP, PM10, PM2.5 were 0.08~0.10%, 0.16~0.20% and 0.18~0.26%, respectively). Note that we assumed that the 1% of household wastes is emitted by open burning.

Laboratory/Field evaluation and calibration method of low-cost PM sensor for indoor PM2.5, PM10 measurement (실내 미세먼지 측정을 위한 저가형 PM 센서의 실험실/현장 평가 및 보정 방법)

  • Doheon, Kim;Dongmin, Shin;Jungho, Hwang
    • Particle and aerosol research
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    • v.18 no.4
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    • pp.109-127
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    • 2022
  • Recently, low-cost particulate matter (PM) sensors have been widely used in monitoring mass concentration. Maintaining the accuracy of the sensors is important and requires rigorous performance evaluation and calibration. In this study, two commercial low-cost PM sensors(LCS), Plantower PMS3003 and Plantower PMS7003, were evaluated in the laboratory and field with a reference-grade PM monitor (GRIMM 11-D). Laboratory evaluation was conducted with single/mixed particles of PSL (Poly Styrene Latex) in an acrylic chamber at 20℃ and relative humidity of 20%. Field evaluation was conducted inside a building of Yonsei University (Shinchon) from February 12 to March 31, 2022. In both evaluations, LCS measured values became different from reference measured values when the relative humidity was high or the outdoor air PM10/PM2.5 ratio was high. Based on the field evaluation, the LCS measured values were corrected through four different regression analysis models. As a result, the multivariate polynomial regression analysis model showed highest matching with the reference PM monitor (PM2.5 >0.9, PM10 >0.85). In this model, the PM10/PM2.5 ratio and relative humidity were chosen as independent variables.

Comparison of Ambient Real-Time PM2.5 Concentrations at Major Roadside with on those at Adjacent Residential Sites in Seoul Metropolitan City (서울시 도로변지역과 인근 주거 밀집지역의 실시간 대기 중 PM2.5농도 비교)

  • Yun, Dongmin;Kim, Bokyeong;Lee, Dongjae;Lee, Seonyeob;Kim, Sungroul
    • Journal of Environmental Science International
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    • v.24 no.7
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    • pp.875-882
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    • 2015
  • In 2013, International Agency for Research on Cancer (IARC) concluded that outdoor air pollution is carcinogenic to humans, with the particulate matter component of air pollution most closely associated with sufficient evidence of increased cancer incidence by exposure to particulate matter component of air pollution. Motor vehicles are one of a major emission sources of fine particle ($PM_{2.5}$) in urban areas. A large number of epidemiological studies have reported a positive association of morbidity or mortality with distance from the roadside. We conducted this study to assess the association of $PM_{2.5}$ concentrations measured at roadside hotspots with those at adjacent residential sites using real-time $PM_{2.5}$ monitors. We conducted real-time $PM_{2.5}$ measurements for rush hour periods (08:00~10:00 and 18:00~20:00) at 9 roadside air monitoring Hotspot sites in metropolitan Seoul over 3 weeks from October 1 to 21, 2013. Simultaneous measurements were conducted in residential sites within a 100 m radius from each roadside air monitoring site. A SidePak AM510 was used for the real-time $PM_{2.5}$ measurements. Medians of roadside $PM_{2.5}$ concentrations ranged from $9.8{\mu}g/m^3$ to $38.3{\mu}g/m^3$, while corresponding median values at adjacent residential sites ranged from $4.4{\mu}g/m^3$ to $37.3{\mu}g/m^3$. $PM_{2.5}$ concentrations of residential sites were 0.97 times of hotspot roadside sites. Distributions of $PM_{2.5}$ concentrations in roadside and residential areas were also very similar. Real-time $PM_{2.5}$ concentrations at residential sites, (100 m adjacent), showed similar levels to those at roadside sites. Increasing the distance between roadside and residential sites, if needed, should be considered to protect urban resident populations from $PM_{2.5}$ emitted by traffic related sources.

Effect of TES Extender on Sperm Characteristics and Viability of Frozen Semen in Miniature Pig (TES 보존액이 미니돼지 동결 융해 정자의 생존성 및 성상에 미치는 영향)

  • Kim, Sang-Hwan;Kang, Hyun-Ah;Lee, Myeong-Seop;Seo, Kang-Suk;Yoon, Jong-Taek
    • Journal of Embryo Transfer
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    • v.27 no.1
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    • pp.45-50
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    • 2012
  • The objective of this study is to estimate the effect of adding TES to LEY and FGE freezing extender for the sperm viability, acrosomal morphology and DNA fragmentation from miniature pig sperm, we evaluated sperm characteristics in TFGE, TLE and LEY with various thawing condition ($37^{\circ}C$ for 20 sec, 45 sec and $75^{\circ}C$ for 5 sec, respectively), and in different concentration of glycerol at 1%, 1.5%, 3%. The sperm viability and normal acrosome intact(NAI) in TFGE (Viability : $60.3{\pm}2.4$, NAI : $58.6{\pm}2.2%$), TLE ($61.3{\pm}2.4$, $62.2{\pm}2.2%$) extender significantly(p<0.05) increased than that in LEY ($50.2{\pm}2.4$, $54.5{\pm}2.2%$) extender thawed at $75^{\circ}C$ for 5 sec. According to the results from glycerol concentration, the viability and NAI of miniature pig sperm in 1.5% glycerol TLE ($66.1{\pm}3.2$, $66.2{\pm}1.0%$) was highest among the experimental groups. In accordance with this, DNA fragmentation rates was the lowest in TLE ($43.3{\pm}0.5%$) while that in LEY ($63.5{\pm}2.3%$) is the highest. Therefore, these results suggest that TLE extender method for freezing- thawing of miniature pig sperm increased the viability after thawing.

Mortality Burden Due to Short-term Exposure to Fine Particulate Matter in Korea

  • Jongmin Oh;Youn-Hee Lim;Changwoo Han;Dong-Wook Lee;Jisun Myung;Yun-Chul Hong;Soontae Kim;Hyun-Joo Bae
    • Journal of Preventive Medicine and Public Health
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    • v.57 no.2
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    • pp.185-196
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    • 2024
  • Objectives: Excess mortality associated with long-term exposure to fine particulate matter (PM2.5) has been documented. However, research on the disease burden following short-term exposure is scarce. We investigated the cause-specific mortality burden of short-term exposure to PM2.5 by considering the potential non-linear concentration-response relationship in Korea. Methods: Daily cause-specific mortality rates and PM2.5 exposure levels from 2010 to 2019 were collected for 8 Korean cities and 9 provinces. A generalized additive mixed model was employed to estimate the non-linear relationship between PM2.5 exposure and cause-specific mortality levels. We assumed no detrimental health effects of PM2.5 concentrations below 15 ㎍/m3. Overall deaths attributable to short-term PM2.5 exposure were estimated by summing the daily numbers of excess deaths associated with ambient PM2.5 exposure. Results: Of the 2 749 704 recorded deaths, 2 453 686 (89.2%) were non-accidental, 591 267 (21.5%) were cardiovascular, and 141 066 (5.1%) were respiratory in nature. A non-linear relationship was observed between all-cause mortality and exposure to PM2.5 at lag0, whereas linear associations were evident for cause-specific mortalities. Overall, 10 814 all-cause, 7855 non-accidental, 1642 cardiovascular, and 708 respiratory deaths were attributed to short-term exposure to PM2.5. The estimated number of all-cause excess deaths due to short-term PM2.5 exposure in 2019 was 1039 (95% confidence interval, 604 to 1472). Conclusions: Our findings indicate an association between short-term PM2.5 exposure and various mortality rates (all-cause, non-accidental, cardiovascular, and respiratory) in Korea over the period from 2010 to 2019. Consequently, action plans should be developed to reduce deaths attributable to short-term exposure to PM2.5.

A Study on the Acute Effects of Eine Particles on Pulmonary Function of Schoolchildren in Beijing, China (봄철 미세분진이 북경시 아동 폐기능에 미치는 급성영향에 관한 연구)

  • 김대선;유승도;차정훈;안승철;차준석
    • Journal of Environmental Health Sciences
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    • v.30 no.2
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    • pp.140-148
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    • 2004
  • To evaluate the acute effects of fine particles on pulmonary function, a longitudinal study was conducted. This study was carried out for the schoolchildren (3rd and 6th grades) living in Beijing, China. Each child was provided with a mini-Wright peak flow meter and a preformatted health symptom diary for 40 days, and was trained on their proper use. Participants were instructed to perform the peak flow test three times in standing position, three times a day (9 am, 12 pm, and 8 pm), and to record all the readings along with the symptoms (cold, cough, and asthmatic symptoms) experienced on that day. Daily measurement of fine particles (PM$_{10}$ and PM$_{2.5}$) was obtained in the comer of the playground of the participating elementary school for the same period of this longitudinal study. The relationship between daily peak expiratory flow rate (PEFR) and fine particle levels was analyzed using a mixed linear regression models including gender, height, the presence of respiratory symptoms, and daily average temperature and relative humidity as extraneous variables. The total number of students participating in this longitudinal study was 87. The range of daily measured PEFR was 253-501$\ell$/min. In general, the PEFR measured in the morning was lower than the PEFR measured in the evening (or afternoon) on the same day. The daily mean concentrations of PM$_{10}$ and PM$_{2.5}$ over the study period were 180.2$\mu\textrm{g}$/㎥ and 103.2$\mu\textrm{g}$/㎥, respectively. The IQR (inter-quartile range) of PM$_{10}$ and PM$_{2.5}$ were 91.8$\mu\textrm{g}$/㎥ and 58.0$\mu\textrm{g}$/㎥. During the study period, the national ambient air quality standard of 150$\mu\textrm{g}$/㎥ (for PM$_{10}$) was exceeded in 23 days (57.5%). The analysis showed that an increase of 1$\mu\textrm{g}$/㎥ of PM$_{10}$ corresponded to 0.59$\mu\textrm{g}$/㎥ increment of PM$_{2.5}$. Daily mean PEFR was regressed with the 24-hour average PM$_{10}$ (or PM$_{2.5}$) levels, weather information such as air temperature and relative humidity, and individual characteristics including gender, height, and respiratory symptoms. The analysis showed that the increase of fine particle concentrations was negatively associated with the variability in PEFR. The IQR increments of PM$_{10}$ or PM$_{2.5}$ (at 1-day time lag) were also shown to be related with 1.54 $\ell$/min (95% Confidence intervals: 0.94-2.14) and 1.56$\ell$/min (95% CI: 0.95-2.16) decline in PEFR.R.ine in PEFR.ine in PEFR.

A Study for the Norms of Audiometric Tests in Koreans (정상한국인의 청력검사치에 관한 연구)

  • 오혜경;서장수;이근해;김희남;김영명;권영화;서옥기
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1981.05a
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    • pp.38.1-38
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    • 1981
  • Currently in the otologic field, there are various methods of special audiometric examinations, such as, tone decay, SISI, and impedance audiometry and only a few studies has been done in these fields sporadically in Korea. The purpose of this paper is to establish norms of various special audiometric tests, so we have performed the special audiometric tests on 100 male medical students in good physical condition and the follow results were obtained. 1. All cases showed over 90% of PB scores. The mean and its 2 S.D. were 98$\pm$4.9% in the right ear and 97$\pm$5.6% in the left ear. 2. The mean and its 2 S.D. of MCL(most comfortable level) were 45$\pm$15.4 dB in the right ear and 46$\pm$17.9 dB in the left ear, and its range was 12$\pm$12.2 dB in the right ear and 13$\pm$12.6 dB in the left ear. 3. The mean and its 2 S.D. of UCL (uncomfortable level) were 102$\pm$7.9 dB in the right ear and 102$\pm$7.9 dB in the left ear and about an half in cases showed over 106 dB of UCL. 4. In 95% of cases, SISIs(short increment sensitivity index) at 1, 000 Hz and 4000 Hz was below 45% in the right ear in both frequencies and below 55% and 75% in the left ear, respectively. 5. In 95% of cases, tone decays at 2, 000 Hz and 4, 000 Hz was below 10 dB in both ears. 6. The difference between SRT and PTA (speech reception threshold minus pure tone average) was 4$\pm$9.2 dB in the right ear and 4$\pm$10.0 dB in the left ear. 7. The dynamic range(uncomfortable level minus speech reception threshold) was 98$\pm$13.5 dB in the right ear and 99$\pm$13.5 dB in the left ear. We had trouble in estimating the dynamic range in about an half in cases, in which we couldn't estimate the UCL with our conventional audiometry. 8. The results of impedance audiometric tests were as follow: A. In the tympanogram, all cases were of A type with one exception of B type in the left ear. The mean and its 2 S.D. of its peak level were 22.8$\pm$32.94mm $H_2O$ in the right ear and 23.9$\pm$29. 81mm $H_2O$ in the left ear. B. The mean and its 2 S.D. of the compliance were 0.6$\pm$0.54cc in the right ear and 0.6$\pm$0.53cc in the left ear. C. The results of stapedial reflex: a. The mean and its 2 S.D. of the controlateral stapedial reflex at 500Hz, 1, 000Hz, 2, 000Hz, 4, 000Hz were 99$\pm$17.7 dB, 87$\pm$14.4 dB, 79$\pm$13.7 dB, 77$\pm$20.0 dB in the right ear and 99$\pm$15.9 dB, 88$\pm$13.9 dB, 79$\pm$13.7 dB, 77$\pm$21.3 dB in the left ear. Depending on the tested frequencies, the stapedial reflex wasn't generated in 6 cases in the right ear and 11 cases in the left ear. b. The mean and its 2 S.D. of the ipsilateral stapedial reflex at 1, 000Hz, and 2, 000Hz were 89$\pm$16.3 dB, 82$\pm$15.9 dB in the right ear and 89$\pm$18.0 dB, 83$\pm$18.9 dB in the left ear. Depending on the tested frequencies, the stapedial reflex wans't generated in 1 case in the right ear and 2 cases in the left ear. 9. Eustachian tube function using with impedance audiometry was malfunctioned in21 cases depending on the tested pressure and the range of peak level of tympanogram was 14$\pm$26.9mm $H_2O$(tested pressure:+250mm $H_2O$), 8$\pm$21.9mm $H_2O$ (tested pressure:-250mm $H_2O$) in the right ear and 11 cases depending on the tested pressure and the range of the peak level of tympanogram was 12$\pm$22.5mm $H_2O$ (tested pressure: +250 mm $H_2O$, 9$\pm$17.3mm $H_2O$(tested pressure: -250mm $H_2O$) in the left ear.

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Characteristics of Indoor Particulate Matter Concentrations by Size at an Apartment House During Dusty-Day (황사 발생시 아파트 실내에서 미세먼지 크기별 농도 특성)

  • Joo, Sang-Woo;Ji, Jun-Ho
    • Particle and aerosol research
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    • v.15 no.1
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    • pp.37-44
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    • 2019
  • It is recommended for the public to stay at home and to close the doors and windows when a high-particulate-matter environment such as a yellow sand event occurs outside. However, there are lack of empirical studies describing how much outdoor PM infiltrates into a closed house and how much indoor PM an inhabitant is exposed to during the period. In this study, the $PM_{10}$ and $PM_{2.5}$ were measured at the kitchen in an apartment house by an optical particle counter for 3 days including a yellow sand event. The outdoor PMs and the outdoor wind speeds were referred from surrounding weather stations. We analyzed the penetration of $PM_{10-2.5}$ and $PM_{2.5}$ at the test house against the outdoor wind speed supposed corresponding to the change of air exchange rate. In addition, the effect of an indoor activity on change in the indoor PM was investigated. In result, the indoor $PM_{10-2.5}$ was very low even a yellow sand event occurred outside; rather, a contribution of indoor activities to increase in $PM_{10-2.5}$ was higher. In contrast, the indoor $PM_{2.5}$ fluctuated following the outdoor $PM_{2.5}$ trend at high wind speeds or remained almost constant at low wind speed.