• 한국환경과학회지
• /
• 제26권11호
• /
• pp.1297-1306
• /
• 2017

This study identified physical characteristics and aerosol particle sources of $PM_{10}$ and $PM_{2.5}$ in the industrial complex of Busan Metropolitan City, Korea. Samples of $PM_{10}$, $PM_{2.5}$ and also soil, were collected in several areas during the year of 2012 to investigate elemental composition. A URG cyclone sampler was used for collection. The samples were collected according to each experimental condition, and the analysis method of SEM-EDX was used to determine the concentration of each metallic element. The comparative analysis indicated that their mass concentration ranged from 1% to 3%. The elements in the industrial region that were above 10% were Si, Al, Fe, and Ca. Those below 5% were Na, Mg, and S. The remaining elements (1% of total mass) consisted of elements such as Ni, Co, Br and Pb. Finally, a statistical tool was applied to the elemental results to identify each source for the industrial region. From a principal components analysis (SPSS, Ver 20.0) performed to analyze the possible sources of $PM_{10}$ in the industrial region, five main factors were determined. Factor 1 (Si, Al), which accounted for 15.8% of the total variance, was mostly affected by soil and dust from manufacturing facilities nearby, Factors 2 (Cu, Ni), 3 (Zn, Pb), and 4 (Mn, Fe), which also accounted for some of variance, were mainly related to iron, non-ferrous metals, and other industrial manufacturing sources. Also, five factors determined to access possible sources of $PM_{2.5}$, Factor 1 (Na, S), accounted for 13.5% of the total variance and was affected by sea-salt particles and fuel incineration sources, and Factors 2 (Ti, Mn), 3 (Pb, Cl), 4 (K, Al) also explained significant proportions of the variance. Theses factors mean that the $PM_{2.5}$ emission sources may be considered as sources of incineration, and metals, and non-ferrous manufacturing industries.

• 한국대기환경학회지
• /
• 제33권3호
• /
• pp.277-288
• /
• 2017

Previous studies of health effects of $PM_{2.5}$ performed spatial monitoring campaigns to assess spatial variability of $PM_{2.5}$ across people's residences. Highly reliable portable and cost-effective samplers will be useful for such campaigns. This study aimed to investigate applicability of the Deployable Particulate Impact Sampler(DPIS), one of the compact impact samplers, to spatial monitoring campaigns of $PM_{2.5}$ in Seoul, Korea. The investigation focused on the consistency of $PM_{2.5}$ concentrations measured by DPISs compared to those by the Low-volume Cyclone sampler (LCS). LCS has operated at a fixed site in the Seoul National University Yeongeon campus, Seoul, Korea since 2003 and provided qualified $PM_{2.5}$ data. $PM_{2.5}$ sampling of DPISs was carried out at the same site from November 17, 2015 through February 3, 2016. $PM_{2.5}$ concentrations were quantified by the gravimetric method. Using a duplicated DPIS, we confirmed the reliability of DPIS by computing relative precision and mean square error-based R squared value ($R^2$). Relative precision was one minus the difference of measurements between two samplers relative to the sum. For accuracy, we compared $PM_{2.5}$ concentrations from four DPISs (DPIS_Tg, DPIS_To, DPIS_Qg, and DPIS_Qo) to those of LCS. Four samplers included two types of collection filters(Teflon, T; quartz, Q) and impaction discs(glass fiber filter, g; pre-oiled porous plastic disc, o). We assessed accuracy using accuracy value which is one minus the difference between DPIS and LCS $PM_{2.5}$ relative to LCS $PM_{2.5}$ in addition to $R^2$. DPIS showed high reliability (average precision=97.28%, $R^2=0.98$). Accuracy was generally high for all DPISs (average accuracy=83.78~88.88%, $R^2=0.89{\sim}0.93$) except for DPIS_Qg (77.35~78.35%, 0.82~0.84). Our results of high accuracy of DPIS compared to LCS suggested that DPIS will help the assessment of people's individual exposure to $PM_{2.5}$ in extensive spatial monitoring campaigns.

• 한국패류학회지
• /
• 제28권4호
• /
• pp.313-319
• /
• 2012

2001년 8월 8일부터 12월 5일까지 말백합 대량 인공종묘 생산 실험을 실시하였다. 채란은 평균각장 $65.8{\pm}8.4mm$의 어미 100 개체로부터 공기노출과 수온상승자극 방법으로 채란 하였으며, 수정란에서 D형유생까지 발생 소요시간은 수온 $27^{\circ}C$에서 17시간 40분, 발생률은 6.1%, D형유생은 각장 $131.4{\pm}2.6{\mu}m$였다. D형유생은 4일간 사육하여 각장 $190.2{\pm}7.5{\mu}m$의 침착기 유생으로 성장하였고, 생존율은 48.1%였다. 이후 침착기 유생 130,000 개체를 저면 모래순환여과 방법으로 침착시켜 사육하였으며, 46일째 평균각장 $3.1{\pm}0.8mm$, 87일째 $6.6{\pm}1.8mm$, 그리고 114일째에 $10.5{\pm}0.9mm$로 성장하였다. 치패의 각장 (SL) 에 대한 각고(SH) 의 상대성장식은 SH = 0.8501SL + 0.0196 ($R^2=0.9987$)로 나타났다. 초기 침착치패인 각장 3.1 mm 이하에서 대량폐사가 일어났으며, 생존율은 사육 46일째 53.8%, 87일째 43.6%, 그리고 114일째에 51,000 개체가 생존하여 생존율 39.2%를 나타냈다.

• 한국수정란이식학회지
• /
• 제12권2호
• /
• pp.195-202
• /
• 1997

The present study was carried out to evaluate the effect of superovulation treatments on ovarian responses, oocyte recovery rates and grades of collected oocytes using an ultrasound-guided transvaginal approach in Korean native cows. Superovulation in cows was induced with two different regimenes: 1) FSH-decreasing dose(n=8): the cows were received twice per day for three days of the total dose of 400 mg of FSH-p, 2) FSH-single dose(n=9): the cows were administrated a single dose of 400 mg of FSH-p in 25% PVP. The Observation of visible follicles and collection of oocytes were performed 12 hours following the last FSH in FSH-decreasing dose group and 48 hours after the FSH-single dose injection. All visible follicles larger than 6 mm were punctured and aspirated with a 6.5 MHz convex-array ultrasound transducer designed for intravaginal use. The mean number of visible follicles(> 6 mm) was significantly(P<0.05) higher in the FSH-decreasing dose treatment (22.811.9) and FSH-single dose treatment (20.612.0) groups than the non-treatment group(7.0$\pm$8). The mean recovery rate of oocytes was not significantly(P<0.05) different between the treatment and control groups, but the mean number of collected oocytes was significantly(P<0.05) higher in the FSH-decreasing dose treatment( 12.611.5) and FSH-single dose treatment (11.813.6) groups than the non-treatment group(3.7$\pm$0.5). In conclusion, the FSH-single dose treatment at superovulation in cows for ultrasound-guided aspiration might increase the number of aspiratable follicles and the recovery rate of follicular oocytes as the FSH-decreasing dose treatment.

• 한국의학물리학회지:의학물리
• /
• 제7권2호
• /
• pp.29-40
• /
• 1996

조사선량율 5mR/h 이상에서 동작하는 원통형 전리함을 설계ㆍ제작하고 상용의 전류계를 이용하여 전하수집 특성을 조사하였다. 전리함은 전체 길이 15.5cm, 직경 5.22cm인 원통형이고 활성체적은 190.4㎤이다. 전리함의 전극은 벽면, 중심축 및 보호전극으로 구성하고, 이들을 동심축상에 배치하여 바탕전류가 8.39$\times$$10^{-14}$ $\pm$1.5$\times$$10^{-15}$ A이 되게 하였다. 전리함에 인가된 전입이 400V일 때 Cs$^{137}$에 대하여 99.7%의 수집효율을 보였으며, 상용의 선량계와 비교한 결과 교정정수 4.531$\times$19$^{7}$ R/C를 구하였다. 에너지 응답특성은 Cs$^{137}$ 을 1로 하였을 때 Am$^{241}$과 Co$^{60}$ 는 각각 1.30, 1.05로 나타났다. 방사선이 전리함의 측면으로 입사할 경우 입사방향에 따른 응답특성의 차이는 무시할 수 있었다.

• 대한화학회지
• /
• 제58권3호
• /
• pp.267-276
• /
• 2014

국내 배경지역인 제주도 한라산 1100 고지에서 2012년 가을철에 $PM_{10}$, $PM_{2.5}$ 미세먼지를 채취하여 이온 및 원소 성분을 분석한 결과로부터 대기경계층(ABL) 미세먼지의 화학조성과 입자크기별 분포 특성을 조사하였다. $PM_{2.5}$ 미세입자($d_p$ < $2.5{\mu}m$)에서는 2차 오염물질인 nss-$SO{_4}^{2-}$, $NH_4{^+}$, $NO_3{^-}$ 농도가 각각 4.84, 1.98, $1.27{\mu}g/m^3$로 상대적으로 높고, 전체 질량의 58.2%를 차지하였다. 반면에 $PM_{10-2.5}$ 조대입자($2.5{\mu}m$ < $d_p$ < $10{\mu}m$)에서는 이들 세 성분의 농도가 각각 0.63, 0.21, $1.10{\mu}g/m^3$로 전체 질량의 22.8%를 차지하였다. 또 수용성 이온성분들 중 $NH_4{^+}$, nss-$SO{_4}^{2-}$, $K^+$, $CH_3COO^-$은 주로 미세입자에 분포하고, $NO_3{^-}$은 미세입자와 조대입자에 고르게 분포하나, $Na^+$, $Cl^-$, $Mg^{2+}$, nss-$Ca^{2+}$은 조대입자에 더 많이 분포하는 특징을 나타내었다.

• 한국콘텐츠학회논문지
• /
• 제16권3호
• /
• pp.354-365
• /
• 2016

건강소비자의 고품질 간호요구가 증대됨에 따라 전문간호사 제도가 시행된 이후 전문간호사의 직무에 대한 임파워먼트, 직무만족, 조직몰입의 수준을 파악하고 일반간호사와 비교한 연구가 필요한 시점이다. 이에 본 연구는 서울과 인천지역의 6개 상급종합병원과 4개 종합병원의 전문간호사와 간호사를 대상으로 직접 배포하거나 이메일을 통해 설문지를 받아 분석하였다. SPSS 18.0을 사용하여 t 검정과 ANOVA 분석을 실시하였다. 임파워먼트 평균은 전문간호사($3.56{\pm}0.53$)와 간호사($3.50{\pm}0.54$)간에 유의한 차이가 없었다(t =-. 861, p = 0.390). 직무만족 평균도 전문간호사($3.36{\pm}0.53$)와 간호사($3.25{\pm}0.46$)간에 유의한 차이가 없었다(t =- 1.575, p = 0.117). 조직몰입 평균도 전문간호사($3.11{\pm}0.34$)와 간호사($3.05{\pm}0.36$)간에 유의한 차이가 없었다(t =- 1.301, p = 0.195). 임파워먼트, 직무만족, 조직몰입 모두 전문간호사와 일반간호사 집단간 유의한 차이가 없었다. 이는 한국에서 전문간호사 역할이 명확하게 정립되어 있지 않고 고용과 보상이 적절하지 않은 점과 전문간호사 제도의 운용과 효율이 부족한 실정에 기인한다고 생각된다.

• Childhood Kidney Diseases
• /
• 제7권1호
• /
• pp.9-15
• /
• 2003

목적 : PAN-induced nephrosis 쥐 모델에서 HMG-CoA reductase inhibitor로 작용하여 콜레스테롤을 낮추는 약제로 알려진 atorvastatin을 투여함으로써, 지질대사에 대한 효과와 지질대사의 변화가 쥐 모델의 신장 변화에 미치는 영향을 알아보고자 하였다. 대상 및 방법 : 수컷 Sprague-Dawley 흰쥐를 사용하여 대조군(I군), PAN 단독 투여군(II군), PAN과 atrovastatin 동시 투여군(III군) 3군으로 나누었으며, PAN은 체중 100 gm 당 2 mg을 첫 피하 주사한 후 1, 3, 5, 7, 9주에 반복하여 피하 주사하였으며, atorvastatin은 체중 100 gm당 5 mg을 물에 녹여 매일 경구 투여하였다. 실험 개시 후 11주에 24시간 소변과 혈액을 채취한 다음 신장을 적출 하였으며, 소변의 protein과 creatinine 그리고 혈청의 albumin, BUN, creatinine, lipid profiles를 측정하고, 신장의 형태학적 변화를 관찰하였다. 결과 : 혈청 총 콜레스테롤은 II군이 $291{\pm}173\;mg/dL$, III군이 $167{\pm}72\;mg/dL$, LDL은 II군이 $57{\pm}53\;mg/dL$, III군이 $27{\pm}12\;mg/dL$로 II군 보다 III군에서 감소하였으나 통계학적으로 유의하지는 않았다. 광학 현미경 검사상 사구체 경화의 빈도는 II군이 26.2%, III군이 13.3%로 II군보다 III군에서 적게 나타났다. 결론 : Atorvastatin을 puromycin과 같이 투여한 경우 총 콜레스테롤과 LDL을 낮추었으며 사구체 경화의 빈도도 감소시킨 것으로 보아 고지혈증이 사구체 경화성 변화에 중요한 원인 중의 하나로 생각된다.

• Fisheries and Aquatic Sciences
• /
• 제19권6호
• /
• pp.27.1-27.8
• /
• 2016

Apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude lipid, energy, essential amino acids, and fatty acids in extruded pellets containing various fish meals were determined for olive flounder (Paralichthys olivaceus). Eight extruded pellet diets were prepared to contain different fish meals (herring fish meal, anchovy fish meal, mackerel fish meal, sardine fish meal-A, sardine fish meal-B, tuna fish meal, pollock fish meal-A, and pollock fish meal-B) designated as HM, AM, MM, SM-A, SM-B, TM, PM-A, and PM-B, respectively. Chromic oxide ($Cr_2O_3$) was used as an inert indicator at a concentration of 0.5 % in the diet. Feces were collected from triplicate groups of fish ($151{\pm}4.0g$) using a fecal collection column attached to the fish rearing tank for 4 weeks. Dry matter ADCs of the MM, SM-A, SM-B, and PM-A diets were higher than those of all the other dietary groups, and the lowest digestibility of dry matter was observed in the PM-B diet. Fish fed the MM, SM-A, and PM-A diets showed significantly higher ADC of protein than those fed the AM, SM-B, TM, and PM-B diets. Lipid ADC of PM-B was significantly lower than that of the other diets. Energy ADCs of fish fed the MM, SM-A, and PM-A diets were significantly higher than those of the other diets. The availability of essential amino acids in the MM, SM-A, and PM-A diets were generally higher than that of the other fish meal diets, while TM showed the lowest values among all the experimental diets. ADCs of fatty acids in the AM, MM, SM-A, and PM-A diets were generally higher than those of fatty acids in the other diets, and the lowest values were recorded for the PM-B diet. These results provide information on the bioavailability of nutrients and energy in various fish meals which can be used to properly formulate practical extruded feeds for olive flounder.

• Asian-Australasian Journal of Animal Sciences
• /
• 제21권3호
• /
• pp.434-442
• /
• 2008

The objective of this study was to determine the optimum ratio of methionine to methionine plus cystine for growing pigs. A nitrogen balance trial was conducted using a total of 21 barrows (Large WhiteLandrace) over two replicates. The initial body weight was $20.36{\pm}1.22kg$ (mean${\pm}$SD) in the first replicate and $23.54{\pm}1.02kg$ (mean${\pm}$SD) in the second. For each replicate, the 21 pigs were randomly assigned to one of seven dietary treatments with three observations per treatment. The diets included a methionine and cystine-deficient basal diet with all other essential nutrients meeting nutrient requirements and six diets formulated with graded levels of DL-methionine (0.00, 0.03, 0.06, 0.10, 0.13, 0.16%) and $L-Cystine{\cdot}HCl{\cdot}H_2O$ (0.19, 0.15, 0.11, 0.07, 0.04, 0.00%). This resulted in ratios of methionine to methionine plus cystine of 41.3, 29.6, 35.3, 41.2, 46.0, 51.6 and 57.5%. Each experimental period lasted 12 days consisting of a seven-day adaptation period followed by a five-day total collection of urine and feces. During the collection period, pigs were fed 900 g/day for the first replicate and 1,200 g/day for the second replicate. The feed was provided in three equal portions at 0800, 1500, and 2200 h daily. Pigs had ad libitum access to water after feeding. There was a linear (p<0.01) and quadratic (p<0.01) effect on daily gain and feed conversion as the ratio of methionine to methionine plus cystine increased. Pigs receiving the diets providing a methionine to methionine plus cystine ratio of 51.6% had the best daily gain and feed conversion. Plasma urea nitrogen was also lowest for this treatment. Nitrogen retention increased (p<0.01) as the relative proportion of methionine increased up to 51.6% and then a downward trend occurred at 57.5%. The quadratic regression model, as well as one- and two- slope regression line models, were used to determine the optimum ratio of methionine to methionine plus cystine. Eliminating the 35.3% methionine to methionine plus cystine treatment resulted in $R^2$ values in excess of 0.92. The optimal ratio of methionine to methionine plus cystine was estimated to be 54.15% for nitrogen retention and 56.72% for plasma urea nitrogen.