• Title/Summary/Keyword: $PM_{10}$$PM_{2.5}$$PM_1$

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The Evaluation of Image Quality and Radiation Dose in Multi-Detector CT (MDCT에서 화질과 방사선량에 관한 연구)

  • Han, Dong-Kyoon;Yang, Han-Joon;Kim, Moon-Chan;Ko, Shin-Gwan
    • Journal of radiological science and technology
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    • v.30 no.2
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    • pp.129-138
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    • 2007
  • The Purpose of this study is to suggest the basic data for making good quality image and maintaining equipment homeostasis by accepting image quality evaluation and radiation dose evaluation in Multi-detector CT. In this study we surveyed 14 CT equipments in Seoul. The results obtained were as follows ; CT number was $0.56{\pm}0.70\;HU$. Noise was $0.39{\pm}0.09\;HU$. Uniformity was $1.08{\pm}0.52\;HU$. High contrast resolution was $0.48{\pm}0.05\;mm$ and low contrast resolution was $3.65{\pm}1.16\;mm$. For CTDI, the central part and the peripheral part of head phantom were $43.2{\pm}15.4\;mGy$ and $45.6{\pm}17.5\;mGy$, respectively. For body phantom, the central part and the peripheral part of head phantom were $13.5{\pm}4.5$ and $29.2{\pm}10.2\;mGy$, respectively. CTDIw was $44.8{\pm}16.8\;mGy$ and CTDIw/100 mAs was $18.8{\pm}5.3\;mGy$ using head phantom. CTDIW was $24.0{\pm}8.3\;mGy$ and CTDIw/100 mAs was $10.1{\pm}2.5\;mGy$ using body phantom. Therefore, CT number, noise, high contrast resolution, low contrast resolution, CTDI, CTDIw and CTDIw/100 mAs of MDCT were showed excellently in all equipments.

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Potential Source of PM10, PM2.5, and OC and EC in Seoul During Spring 2016 (2016년 봄철 서울의 PM10, PM2.5 및 OC와 EC 배출원 기여도 추정)

  • Ham, Jeeyoung;Lee, Hae Jung;Cha, Joo Wan;Ryoo, Sang-Boom
    • Atmosphere
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    • v.27 no.1
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    • pp.41-54
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    • 2017
  • Organic carbon (OC) and elemental carbon (EC) in $PM_{2.5}$ were measured using Sunset OC/EC Field Analyzer at Seoul Hwangsa Monitoring Center from March to April, 2016. The mean concentrations of OC and EC during the entire period were $4.4{\pm}2.0{\mu}gC\;m^{-3}$ and $1.4{\pm}0.6{\mu}gC\;m^{-3}$, respectively. OC/EC ratio was $3.4{\pm}1.0$. The average concentrations of $PM_{10}$ and $PM_{2.5}$ were $57.4{\pm}25.9$ and $39.7{\pm}19.8{\mu}g\;m^{-3}$, respectively, which were detected by an optical particle counter. The OC and EC peaks were observed in the morning, which were impacted by vehicle emission, however, their diurnal variations were not noticeable. This is determined to be contributed by the long-range transported OC or secondary formation via photochemical reaction by volatile organic compounds at afternoon. A conditional probability function (CPF) model was used to identify the local source of pollution. High concentrations of $PM_{10}$ and $PM_{2.5}$ were observed from the westerly wind, regardless of wind speed. When wind velocity was high, a mixing plume of dust and pollution during long-range transport from China in spring was observed. In contrast, pollution in low wind velocity was from local source, regardless of direction. To know the effect of long-range transport on pollution, a concentration weighted trajectory (CWT) model was analyzed based on a potential source contribution function (PSCF) model in which 75 percentiles high concentration was picked out for CWT analysis. $PM_{10}$, $PM_{2.5}$, OC, and EC were dominantly contributed from China in spring, and EC results were similar in both PSCF and CWT. In conclusion, Seoul air quality in spring was mainly affected by a mixture of local pollution and anthropogenic pollutants originated in China than the Asian dust.

Studies on the Morphology and Stainability of Chicken Spermatozoa (닭 정자(精子)의 형태(形態)와 염색성(染色性) 조사(調査))

  • Kwak, Soo-dong
    • Korean Journal of Veterinary Research
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    • v.27 no.1
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    • pp.1-7
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    • 1987
  • The present studies were designed to investigate the morphology and stainability of the chicken spermatozoa. Semen samples were collected by abdominal massage from 10 cocks of Arbor, Acres strain (egg breed) and 10 cocks of white Cornish strain (meat breed). The semen samples were diluted with Sarker's solution and were washed. Some of the semen smear slides were stained with seven differential stain methods and was compared with one another by light microscope. In addition to the staining already compared, the length of heads, middle pieces and tails of 400 spermatozoa of two chicken breed was measured with micrometer. The results obtained from these, studies were as follows: 1. Eosin stain appeared to give good results than hematoxylin, pre-treated protease and eosin or hematoxylin stain, pre-treated protease and hematoxylin-eosin stain, carbol-fuchsin, stain and Giemsa 9 technique in differential staining of spermatozoal three portions and pre-treated protease and eosin stain appeared as good staining methods for middle piece of spermatozoa. 2. The average length of chicken spermatozoa was $90.4{\pm}4.0{\mu}m$, and the average length of the head, middle piece and tail of spermatozoa was $13.0{\pm}0.5{\mu}m$, $3.8{\pm}0.2{\mu}m$ and $73.6{\pm}3.8{\mu}m$ lesoectively. 3. The average length of spermatozoa of Arbor Acres strain was $89.2{\pm}5.0{\mu}m$ and the average length of the head, middle piece and tail of spermatozoa was $12.9{\pm}0.5{\mu}m$, $3.8{\pm}0.2{\mu}m$ and $72.5{\pm}4.7{\mu}m$ respectively. The average length of spermatozoa of with Cornish was $91.6{\pm}3.0{\mu}m$ and the average length of the head, middle piece and tail of spermatozoa was $13.1{\pm}0.5{\mu}m$, $3.8{\pm}0.2{\mu}m$ and $74.7{\pm}2.8{\mu}m$ respectively.

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The Growth of Mugil cephalus, Patinopecten yessoensis and Saccharina japonica in the IMTA System

  • Kim, Young Dae;Park, Mi Seon;Min, Byung Hwa;kim, Hyung Chul;Lee, Won Chan;Lee, Chu;Kim, Gi Seung;Do, Yong Hyun;Yoo, Hyun Il
    • Journal of Environmental Science International
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    • v.25 no.10
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    • pp.1445-1457
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    • 2016
  • In this study, we investigated the growth of striped mullet (Mugil cephalus), Yesso scallop (Patinopecten yessoensis) and kelp (Saccharina japonica) farmed under the IMTA (integrated multi-trophic aquaculture) system developed by national institute of fisheries science (NIFS). The farmed striped mullets grew from an initial length and weight of $152.5{\pm}12.1mm$ and $41.6{\pm}7.8g$ in October 2013 to $154.2{\pm}5.6mm$ and $47.5{\pm}8.6g$ in November, $160.2{\pm}8.7mm$ and $55.9{\pm}9.1g$ in December and $168.4{\pm}9.6mm$ and $58.4{\pm}8.7g$ in January. The fish continued to grow and reached $190.2{\pm}9.4mm$ in length and $87.5{\pm}8.9g$ in weight in April and $256.4{\pm}9.7mm$ and $156.7{\pm}6.7g$ in October 2014. The daily growth rate (DGR) for total fish length was 0.015~0.1 mm/day during the periods of fast growth and attained 0.038~0.1 mm/day during February ~ March. The kelp grew from an initial blade length and wet weight of $1.19{\pm}0.2cm$ and $0.0028{\pm}0.0012g$ in January 2014 to $3.3{\pm}0.8cm$ and $2.5{\pm}0.9g$ in February and $126.5{\pm}11.6cm$ and $107.4{\pm}22.6g$ in March, after which, erosion occurred and slowed the growth. The DGRs for kelp length ranged 0.03~1.9 mm/day in January 2014 and increased to 0.88~1.9 mm/day during March~April. Increasing water temperatures beginning in April lowered the DGR to 0.03 mm/day. Yesso scallops grew from an initial shell length, shell height and wet weight of $11.83{\pm}0.6mm$, $12.68{\pm}0.7mm$ and in September 2013 to $19.9{\pm}2.5mm$, $20.8{\pm}2.6mm$ and $0.9{\pm}0.04g$ in November 2013. They continued to grow to $45.91{\pm}0.71mm$ in shell length, $42.55{\pm}0.8mm$ in shell height and $12.7{\pm}1.3g$ in wet weight by May 2014 and $60.2{\pm}2.51mm$, $554.6{\pm}2.61mm$ and $24{\pm}2.70g$ by October 2014. The DGRs for shell length of Yesso scallop ranged from 0.02 to 0.256 mm/day with higher values of 0.256~0.27 mm/day during November~December 2013 and March~April 2014.

A study on the epidemiology of caprine anaplasmosis in Korea III. Seasonal variation in hematologic profiles (산양의 anaplasmosis에 대한 역학적 조사 III. 혈액치의 계절적 변화)

  • Baek, Byeong-kirl;Son, Ku-rey
    • Korean Journal of Veterinary Research
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    • v.35 no.1
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    • pp.137-142
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    • 1995
  • Anaplasmosis is a tick-borne disease of large and small ruminants, causing losses through mortality, abortion, weight loss and reduced milk production. In one dairy farm, for example, 250 of a total of 800 imported goats were diagnosed with a mysterious type of anemia during the summer and autumn of 1992. The etiologic agent was identified as Anaplasma spp by acridine orange and ultrastructure by electron microscopy. In order to monitor variations in blood biochemical and hematological parameters associated with the disease, blood samples were collected by jugular venipuncture from 50 goats at 3 month intervals between the period of February and October, 1993. The levels of RBCs, HB and HCT decreased from $18.48{\pm}1.96$ to $13.47{\pm}2.48X10^6/mm^3$, $12.25{\pm}1.41$ to $9.54{\pm}1.77g/dl$, and $43.09{\pm}4.75$ to $30.93{\pm}5.78%$, respectively. The values of MCH(Mean corpuscular hemoglobin), MCHC(Mean corpuscular hemoglobin concentration) and PLT(Platelet) were elevated from $6.58{\pm}0.30$ to $7.05{\pm}0.47pg$, $28.40{\pm}1.20$ to $30.82{\pm}1.85g/dl$ and $1688.34{\pm}750$ to $2046.82{\pm}783X10^3/mm^3$, respectively. Percent parasitized erythrocytes(PPE) increased from $0.61{\pm}0.5$ to $2.22{\pm}1.9%$, clinical biochemical parameters aspartate aminotransferase and alanine aminotransferase were $66.64{\pm}23.1K.U$ and $14.90{\pm}6.59K.U$, respectively and persisted at high levels throughout the observation period. The level of albumin(2.46)0.52 g/dl) was decreased corresponding to an elevated globulin and a reduced albumin/globulin ratio in October as compared with the values in February. It is concluded that caprine anaplasmosis may be an important cause of anemia and hepatic malfunction in goats.

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Antioxidative and Antiallergic Effect of Persimmon Leaf Extracts (감잎(Diospyros kaki Thunb) 추출물의 항산화 및 항알레르기 효과)

  • Yoo, Ki-Hwan;Jeong, Jong-Moon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.12
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    • pp.1691-1698
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    • 2009
  • The purpose of this study was to investigate the antioxidative and antiallergic effects of persimmon leaf extract. Antioxidative and anti-inflammatory effects of the crude persimmon leaf extract (PLE) and the partially purified persimmon leaf extract (PPLE) were determined in in vitro assays by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide anion radicals, and 5-lipoxygenase (5-LO) and cyclooxygenase (COX). Total phenols and total flavonoid levels of PLE and PPLE were $230.0{\pm}19.6$ mg/g and $475.5{\pm}38.7$ mg/g, and $34.8{\pm}6.5$ mg/g and $78.8{\pm}3.6$ mg/g, respectively. DPPH and superoxide radical-scavenging activities ($SC_{50}$) of the PLE and PPLE were $23.8{\pm}3.2$ ppm and $10.0{\pm}1.3$ ppm, and $47.6{\pm}3.4$ ppm and $22.4{\pm}3.3$ ppm, respectively. Inhibitory activities ($IC_{50}$) of PLE and PPLE against 5-LO, COX-1 and COX-2 were $77.1{\pm}11.7$, $38.6{\pm}7.0$ ppm, $47.4{\pm}7.7$, $25.3{\pm}6.3$ ppm, and $129.5{\pm}5.5$, $84.5{\pm}2.3$ ppm, respectively. Moreover, two extracts inhibited dose-dependently NO production in LPS-stimulated RAW 264.7 cells, and also effectively inhibited the cutaneous anaphylaxis reaction activated by anti-dinitrophenyl IgE antibody in mice. These results suggest that PLE and PPLE may be useful for phytochemical materials for prevention and treatment of radical-mediated pathological and allergy diseases.

Effect of Oxygenation of Cardioplegic Solution on Electrical Stability and Postischemic Recovery of Cardiac Function after Ischemic Arrest in Isolated Rat Heart[ I ] (백서의 적출된 심장에서 심정지액의 산소화가 허혈성 심정지후 심기능 회복에 미치는 영향[I])

  • 윤재도
    • Journal of Chest Surgery
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    • v.25 no.2
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    • pp.125-130
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    • 1992
  • To evaluate the effect of oxygenation[95% O2+5% CO2] of St. Thomas Hospital No.2 cardioplegic solution[Plegisol], 20 isolated perfused rat hearts were studied under hyp-othermic[20oC] ischemic arrest for 2 hours with infusion of cardioplegic solution every 30 minutes throughout the ischemic period. Ten isolated hearts were studied with the oxygenated cardioplegic solution and 10 another isolated hearts with the nonoxygenated one. Mean oxygen tensions of the nonoxygenated and oxygenated cardioplegic solutions were 150mmHg and 470mmHg, respectively. Two in 10 hearts infused with the nonaxygenated cardioplegic solution were not recovered from nonworking heart due to persistent ventricular fibrillation. In comparing hem-odynamic parameters between both groups, the mean postischemic recovery[expressed as a percentage of its preischemic control value] was significantly greater with the oxygenated solution[in 10 recovered hearts] than the nonoxygenated solution[in 8 recovered hearts] [95.9$\pm$1.8% compared with 88.5$\pm$2.9% in peak aortic pressure, p<0.05, 75.7$\pm$5.2% compared with 43.5$\pm$6.5% in aortic flow, p<0.01, 75.5$\pm$4.6% compared with 54.1$\pm$5.6% in cardiac output, p<0.01, 78.3$\pm$4.6% compared with 60.3$\pm$4.6% compared with 60.3$\pm$6.2% in stroke volume, p<0.05, and 80.4$\pm$5.3% compared with 58.6$\pm$7.0% in dP/dT, p<0.05]. It is concluded that oxygenation of St. Thomas Hospital No.2 cardioplegic solution improves cardiac electrical stability and postischemic hemodynamic recovery after ischemic arrest in the isolated perfused rat heart.

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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.

Analysis on the Characteristics of PM10 Variation over South Korea from 2010 to 2014 using WRF-CMAQ: Focusing on the Analysis of Meteorological Factors (기상-대기질 모델을 활용한 2010~2014년 우리나라 PM10 변동 특성 분석: 기상 요인을 중심으로)

  • Nam, Ki-Pyo;Lee, Dae-Gyun;Park, Ji-Hoon
    • Journal of Environmental Impact Assessment
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    • v.27 no.5
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    • pp.509-520
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    • 2018
  • The impact of meteorological condition on surface $PM_{10}$ concentrations in South Korea was quantitatively simulated from 2010 to 2014 using WRF (ver.3.8.1) and CMAQ (5.0.2) model. The result showed that seasonal standard deviations of PM10 induced by change of weather conditions were $4.8{\mu}g/m^3$, $1.7{\mu}g/m^3$, $1.7{\mu}g/m^3$, $4.2{\mu}g/m^3$ for spring, summer, autumn and winter compared to 2010, respectively, with the annual mean standard deviation of about $2.6{\mu}g/m^3$. The results of 18 regions in South Korea showed standard deviation of more than $1{\mu}g/m^3$ in all regions and more than $2{\mu}g/m^3$ in Seoul, Northern Gyeonggi, Southern Southern Gyeonggi, Western Gangwon and Northern Chungcheong in South Korea.

Evaluation of the Solitary Pulmonary Nodule by Spiral Computed Topography with Contrast Enhancement (고립성 폐결절의 감별에 있어서 나선형 흉부 전산화 단층촬영시 조영증강의 의의)

  • Song, Kwang Seon;Shin, Kye Chul;Yong, Suk Joong;Ryu, Jeong Seon;Kang, Sin Goo;Kim, Chong Ju;Sung, Ki Joon
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.4
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    • pp.519-526
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    • 1996
  • Background : Clinical and Radiographic studies to differentiate benign from malignant pulmonary nodules have previously focused on clinical status and the morphologic and the computed tomographic attenuation characteristics of the lung nodules. Distinctive differences in the vascularity and pathophysiology of malignant versus benign pulmonary nodules were identified. We evaluated the diagnostic method for differentiating malignant from benign solitary pulmonary nodule by contrast enhancement on the spiral CT. Method : Sixteen patients with solitary pulmonary nodule were examined(Tuberculoma 8, primary lung cancer 8). Serial thin section on the spiral CT was performed before and after(45second, 2min, 5min) the onset of the injection of 100mL of nonionic contrast material(2mL/sec). Results : There was no difference in size of nodule and pre-contrast CT number (Hounsfield unit) between benign and malignant nodules. At forty-five second after the onset of the injection, malignant neoplasms($19.6{\pm}7.9$ HU) enhanced significantly more than tuberculomas($4.9{\pm}9.4$ HU, p=0.008). At 2minute and 5 minute after, malignant neoplasms($34.0{\pm}19.2$HU, $34.0{\pm}15.4$HU) enhanced significantly more than tuberculomas ($6.7{\pm}9.7$HU, p=0.007 and $7.7{\pm}11.5$HU, p=0.011). On cut-off value 20HU(contrast enhancement) 2minute after the injection of contrast media, sensitivity was 87% and specificity was 87%. No correlation between the contrast enhancement and size of the nodules was observed. Conclusion : Studies with the use of an intravenously administered noniodinated contrast medium in examining the enhancement properties of lung nodules was performed. The contrast enhancement was useful in differential diagnosis of solitary pulmonary nodules.

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