• Fisheries and Aquatic Sciences
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• 제10권2호
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• pp.93-101
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• 2007

Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in marine sediments from Mokpo coastal water of Korea. Total and toxic equivalent (TEQ) concentrations of PCDD/Fs ranged from 19.4 to 175pg/g dry weight and ranged from 0.195 to 2.87 pg WHO-TEQ/g dry weight, respectively. These PCDD/F concentrations were below the safety sediment value (20 pg TEQ/g dry weight) of chronic toxicity. A highly significant correlation between the concentrations of PCDD/Fs and total organic carbon (TOC) in marine sediments was observed. Overall PCDD/F concentrations in the sediments were elevated in rivers and at inner locations close to harbors, indicating that these contaminants derived from local discharges of human activities. PCDD/F concentrations measured in our study were lower than those in several industrialized areas in Korea. Nonparametric multidimensional scaling (MDS) ordination showed that combustion processes from industrial complexes are the major source of PCDD/Fs in Mokpo coastal water.

• 한국환경보건학회지
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• 제42권2호
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• pp.102-111
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• 2016

Objectives: This study was conducted to evaluate the use of polyurethane foam disk passive air samplers (PUF PAS) for better measurement of atmospheric polychlorinared dibenzo-p-dioxins/furans (PCDD/Fs) concentrations compared to PUF PAS combined with high volume air samplers (HVS). Methods: Air samples were collected by a low volume air sampler (LVS) and PUF PAS. A total of two pairs were continuously collected for six months, but the PUF was replaced every two months. Results: A good correlation was shown ($R^2=0.8595$, p<0.0001) between atmospheric PCDD/Fs concentration measured by the LVS and PUF PAS. The average air sampling rate ($1.5m^3/day-sampler$) of all PCDD/Fs congeners showed a middle of the means which were measured using a HVS by other researchers in different cities. In addition, the air sampling rates of the LVS for each congener made less difference than did those of the HVS. Conclusion: It was found that measurements using the LVS were less influenced by atmospheric peak PCDD/Fs concentrations. However, trace POPs such as PCDD/Fs may involve relatively large analytical errors in measurement, and as a result the air sampling rate of the respective PCDD/Fs isomer is also likely to involve errors. The method of using a regression straight line between the concentrations obtained from the LVS and those from the PUF PAS was judged higher than the method using the air sampling rate, since the former compensated for the experimental errors in the process of evaluation of atmospheric PCDD/F concentrations using the PUF PAS.

• 대한수의학회지
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• 제24권1호
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• pp.31-35
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• 1984

The hemoglobin phenotype and the gene frequencies of 44 Formosan deer(Cervus nippon) in Kyung-Gi area were examined by using cellulose acetate and starch gel electrophoresis. 1. The method of cellulose acetate electrophoresis was simplier, more clear and preserative than starch gel electrophoresis. 2. The hemoglobin phenotype was appeared 3 types as $Hb^F$ $Hb^{FS}$ and $Hb^S$. The frequencies of appearance were $Hb^F$ 47.7%, $Hb^{FS}$ 47.7% and $Hb^S$ 4.5%, respectively. 3. The genetic factors of hemoglobin were observed as $Hb^F$ and $Hb^S$ and the rates of gene frequencies were 71.6% and 28.4%, respectively.

• 한국대기환경학회지
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• 제31권6호
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• pp.548-561
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• 2015

Atmospheric concentrations of polychlorinated dibezo-p-dioxins and furans (PCDD/Fs) were investigated at urban-residential (Group I: Suwon, Guri and Goyang), industrial (Group II: Ansan, Siheung and Bucheon), urban-rural mixed (Group III: Yangju, Pocheon and Dongducheon) and rural regions (Group IV: Yangpyeong) in Gyeonggi-do from February 2012 to November 2012 quarterly. The concentrations of PCDD/Fs ranged from 0.018 to $0.109pgTEQm^{-3}$ in Group I (mean value: $0.061pgTEQm^{-3}$), 0.059 to $0.367pgTEQm^{-3}$ in Group II (mean value: $0.179pgTEQm^{-3}$), 0.072 to $0.836pgTEQm^{-3}$ in Group III (mean value: $0.334pgTEQm^{-3}$) and 0.014 to $0.066pgTEQm^{-3}$ in Group IV (mean value: $0.034pgTEQm^{-3}$), respectively. In spite of the less PCDD/F emission sources than Group II (industrial regions), the level of PCDD/Fs in urban-rural mixed area showed the highest values with high fluctuation. It's likely that the Group III was affected by fugitive emissions such like biomass burning and unregulated open burning. The mean contribution of particle phase to total PCDD/F concentration was above 83% because most of PCDD/F congeners were partitioned into particle phase. We evaluated their gas-to-particles equilibriums with the regression between the particle-gas partition coefficient, $K_P(m^3{\mu}g^{-1})$ and corresponding subcooled liquid vapor pressure ($P_L$). The logarithm-$K_P$ of PCDD/Fs was poorly correlated with $P_L$ at low ambient temperature (below $10^{\circ}C$) and the slope (m) values for log-log plots of the $K_P$ vs. $P_L$ was steeper in the Group 2 and Group 3 than residential area. It implies that the slope values were likely influenced by both the direct emission source of PCDD/Fs and ambient temperature.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권3호
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• pp.201-206
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• 2004

Vascular endothelial growth factor (VEGF), plays a key role in angiogenesis. Many endogenous factors can affect angiogenesis in endothelial cells. VEGF is known to be a strong migration, sprouting, survival, and proliferation factor for endothelial cells during angiogenesis in endothelial cells. Searching for novel genes involved in VEGF signaling during angiogenesis, we carried out differential display polymerase chain reaction on RNA from VEGF-stimulated human umbilical vein endothelial cells (HUVECs). In this study, follistatin (FS) differentially expressed in VEGF-treated HUVECs, compared with controls. Addition of VEGF (10ng/L) produced an approximately 11.8-fold increase of FS mRNA. F5 or VEGF produced approximately 1.8- or 2.9-fold increases, respectively, in matrix metalloproteinase-2 (MMP-2) secretion for 12h, compared to the addition of a control buffer. We suggest that VEGF may affect the angiogenic effect of HUVECs, through a combination of the direct effects of VEGF itself, and the indirect effects mediated via induction of FS in vitro.

• 대한화학회지
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• 제17권1호
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• pp.1-9
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• 1973

區區한 Diels-Alder 反應의 구조를 규명하기 위하여 Diels-Alder 反應 基 自體의 本質에 가장 가깝다고 생각한 새로운 擬似分子化合物이라는 遷移狀態의 模型을 假定하여 Mulliken의 分子化合物의 量子力學을 適用하였다. 이 擬似分子化合物은 이온성과 Radical성을 지닌 混成體이다. 이 混成體의 波動函數는 다음 식으로 표현된다. ${\psi}_{complex} = {\psi}(R,S) + {\rho}{\psi}(R^+,S^-)$ 여기 ${\rho}$는 擬似分子化合物의 極性程度를 나타내는 것이고 이 ${\rho}$가 Diene과 Dienpohile의 反應中心原子들의 自由原子價의 차 $({\Delta}F)$에 關係함을 밝혔다. 아울러 이 ${\Delta}F$量이 Brown氏의 Lp量 및 Dewar氏의 ${\Delta}E_{deloc}$量과 直線성이 있음을 알았다. Diels-Alder反應의 可能性與否를 24組의 反應組에 對하여 豫言하였다. 따라서 우리가 假定한 遷移狀態의 模型이 眞實에 가깝다고 볼 수 있으며 결국 Diels-Alder 反應은 同時附加로 융합된 ionic-Radical mechanism으로 反應이 進行한다고 볼 수 있다.

• 한국재료학회지
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• 제32권2호
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• pp.107-113
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• 2022

Fibrous supercapacitors (FSs), owing to their high power density, good safety characteristic, and high flexibility, have recently been in the spotlight as energy storage devices for wearable electronics. However, despite these advantages, FCs face many challenges related to their active material of carbon fiber (CF). CF has low surface area and poor wettability between electrode and electrolyte, which result in low capacitance and poor long-term stability at high current densities. To overcome these limits, fibrous supercapacitors made using surface-activated CF (FS-SACF) are here suggested; these materials have improved specific surface area and better wettability, obtained by introducing porous structure and oxygen-containing functional groups on the CF surface, respectively, through surface engineering. The FS-SACF shows an improved ion diffusion coefficient and better electrochemical performance, including high specific capacity of 223.6 mF cm^-2 at current density of 10 ㎂ cm^-2, high-rate performance of 171.2 mF cm^-2 at current density of 50.0 ㎂ cm^-2, and remarkable, ultrafast cycling stability (96.2 % after 1,000 cycles at current density of 250.0 ㎂ cm^-2). The excellent electrochemical performance is definitely due to the effects of surface functionalization on CF, leading to improved specific surface area and superior ion diffusion capability.

• 농업과학연구
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• 제22권2호
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• pp.170-179
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• 1995

본 연구는 축협중앙회 한우개량사업소에서 사육하고 있는 한우 238두의 혈청내에 존재하는 혈액 단백질 및 효소의 유전적 다형을 조사하기 위하여, 혈청단백질인 post-transferrin-2(pTf-2), transferrin(Tf), post-albumin(pAlb) 및 albumin(Alb)과 혈청 효소인 ceruloplasmin(Cp) 및 amylase-I(Am-I), 그리고 혈구단백질인 hemoglobin(Hb)을 PAGE(polyacrylamide gel electrophoresis)와 STAGE(starch gel electrophoresis) 방법으로 유전적 다형을 분석하여 이들의 유전자형 및 유전자빈도를 추정하였던바 그 결과는 다음과 같다. 1. 혈청단백질인 pTf-2 좌위는 pTf-2 F와 S의 공우성 대립유전자가 검출되었고, 유전자형은 pTf-2 FF, FS 및 SS 형이 확인되었으며, 이들의 분포는 각각 46.22, 46.64 및 7.14%이었고, 유전자 빈도는 pTf-2 F와 S에서 각각 0.695 및 0.305이었다. 2. Tf 좌위는 Tf A, D1, D2 및 E의 대립유전자가 검출되었으며, 유전자형에 있어서는 Tf AA, ADl, AD2, AE, D1D1, D1D2, D2D2 DIE D2E 및 EE형이 확인되었고, 이들의 분포는 각각 0.84, 13.87, 13.03, 10.92, 22.27, 12.61, 2.94, 15.l3, 6.72 및 1.68%이었으며, 유전자빈도에 있어서는 Tf A, D1, D2 및 E의 빈도가 각각 0.197, 0.430, 0.191 및 0.181이었다. 3. pAlb 좌위는 pAlb F와 S 유전자가 검출되었으며, 유전자형의 분포에 있어서는 pAlb FFFS 및 SS 형이 각각 42.86, 33.19 및 23.95%이었고, 유전자빈도에 있어서는 pAlb F와 S에서 각각 0.595 및 0.405이었으며, Alb에서는 Alb A 유전자 빈도가 1.000이었다. 4. Cp 좌위는 Cp F와 S 유전자가 확인되었으며, 유전자형의 분포는 Cp FF, FS 및 SS 형에서 각각 23.11, 34.87 및 42.02% 이었고, Cp F와 S 유전자빈도는 각각 0.405 및 0.595이었다. 5. Am-I 좌위는 Am-I B와 C 대립유전자가 검출되었으며, 유전자형의 분포는 Am-I BB, BC 및 CC형에서 각각 51.26, 16.81 및 31.93%이었고, 유전자빈도는 Am-I B와 C가 각각 0.597 및 0.403이었다. 6. Hb 좌위는 Hb A와 B 대립유전자가 검출되었으며, 유전자형의 분포는 Hb AA, AB 및 BB형에서 각각 83.19, 16.39 및 0.42%이었고, Hb A와 B의 유전자빈도는 각각 0.914 및 0.086%이었다.

• 전자공학회논문지D
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• 제35D권9호
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• pp.77-86
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• 1998

본 논문에서는 정전용량형 센서 칩과 CMOS 인터페이스 칩으로 구성된 투 칩 집적화 습도 센서를 개발하였다. (100) 실리콘 기판위에 폴리이미드 박막을 이용해서 제작된 습도 센서 칩은 넓은 습도 및 온도 범위에 걸쳐 우수한 직선성(0.72%FS), 낮은 히스테리시스(<3%), 작은 온도계수(-0.0285∼-0.0542 pF/K)를 나타내었다. 40℃/90%RH에서 9주동안 방치한 후 측정된 정전용량은 약 2∼3% 변하였다. 신호처리 회로는 1.2-㎛, one poly double metal CMOS 공정으로 제작하였다. 측정된 센서 출력 전압은 상대습도에 비례해서 변하였으며, 이론치와 잘 일치하였다.

• 한국간호교육학회지
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• 제21권2호
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• pp.246-255
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• 2015

Purpose: The purpose of this study was to investigate differences in the states of anger, depression, resilience and self-esteem according to type of school violence involving elementary school students. Methods: The participants were 257 elementary school students in the 4th, 5th and 6th grades. Data was collected by structured questionnaires, and analyzed using descriptive statistics, ${\chi}^2$-test, t-test, ANOVA, and Pearson correlation coefficients with the SPSS/WIN 20.0 program. Results: There were significant differences among the states of anger (Fs=16.66, p<.001), depression (Fs=18.04, p<.001), resilience (F=12.77, p<.001) and self-esteem (F=10.39, p<.001) according to the type of school violence. Of all the groups, bully-victim exhibited the highest score for anger and depression, and the lowest score for resilience and self-esteem. Conclusion: Based on the findings, developing intervention programs that consider the psychological characteristics of elementary school students is necessary. Also, the results of this study suggest that integrative programs for students that can enhance resilience and self-esteem, such as self-discovery programs, and reduce anger, such as anger control programs, need to be developed.