• 한국산업보건학회지
• /
• 제4권1호
• /
• pp.17-24
• /
• 1994

연폭로자에 있어서 연에 의한 생물학적 영향을 평가하는데는 요중 ${\delta}$-ALA 배설량이 아주 좋은 지표로 이용된다. 현재 이것은 Ehrlich's reagent와 ALA-pyrrole의 증색반응으로 측정하는 비색법이 주로 사용된다. 그러나 이 방법은 aminoacetone 같은 ALA 유사물질에 의하여 요중 배설량이 과다하게 측정된다. 한편 최근 개발된 fluorometric HPLC에 의한 요중 ${\delta}$-ALA 배설량의 분석은 아주 예민하고도 특이적인 것으로 알려져 있다. 따라서 본 연구는 혈중연과 다른 연폭로 지표를 측정하여 연폭로 수준이 다른 117명의 피검자에서 비색법과 HPLC 법에 의한 ${\delta}$-ALA 배설량을 측정하여 두 방법 간의 관련성을 조사하기 위하여 시도하였으며 결과는 다음과 같다. 1. 비색법에 의한 요중의 ${\delta}$-ALA 배설량은 HPLC 법에 비하여 전체적으로 2.15배, 혈중연 $20{\mu}g/dl$ 이하에서 2.47배, $21-40{\mu}g/dl$에서 2.53배, $41{\mu}g/dl$ 이상에서는 1.86배 높은 것으로 측정되었다. 2. 비색법에 의한 요중 ${\delta}$-ALA 배설량과 혈중연 및 혈중 ZPP 농도와의 상관은 0.571, 0.629였으며, HPLC 법은 0.610, 0.637로 통계적 유의성이 있었다(p<0.01). 3. 비색법과 HPLC 법에 의한 요중 ${\delta}$-ALA 배설량 간의 상관은 0.848 이었으며, 요비중으로 보정하였을 때는 0.852였으며 통계적으로 유의하였다(p<0.01). 4. HPLC 법에 의한 요중 ${\delta}$-ALA 배설량을 종속변수로 하고 비색버버을 독립변수로 하였을 때 희기방정식은 (ALA-UHP)=-0.245+0.536 (ALA-UCO)(p<0.0001)였으며, 요비중 1.024로 보정하였을 때의 희기방정식은 (SP ALA-UHP)=-0.525+0.599 (SP ALA-UCO)(p<0.0001)였다. 상기와 같은 결과에서 현행 산업안전보건법 시행규칙에서 연중독 진단을 행하는 경우 HPLC로 요중 ${\delta}$-ALA 배설량을 측정한다면 연중독 진단 기준의 개정이 필요할 것으로 생각된다.

• 육가공
• /
• 통권34호겨울호
• /
• pp.26-39
• /
• 2007

본 실험은 소금 및 GdL의 첨가가 세척 및 가압 처리된 재구성육의 이화학적 특성에 미치는 효과를 규명하고자 실시되었다. 소금 및 GdL의 첨가는 재구성육의 결착강도를 현저하게 증가시켰고, 저염농도 또는 소금이 무첨가 되어도 소량의 GdL의 첨가에 의한 결착강도의 향상을 기대할 수 있었다. 그러나 GdL의 첨가는 색도를 가열처리와 유사하게 변색시켰고, 이러한 변색은 GdL의 증가와 더불어 현저하였다. 그러나 이들 단점은 세척이나 기타 첨가물에 의하여 향상시킬 수 있으리라 판단되었다. 따라서 본 실험의 결과에 의하면 소량의 소금 및 GdL의 조합을 통하여 바람직한 결착강도 및 변색 저하를 기대할 수 있었고, 첨가된 인산염과 carrageenan에 의한 보수력의 향상 효과를 얻을 수 있었다.

• 한국초전도학회:학술대회논문집
• /
• 한국초전도학회 2002년도 High Temperature Superconductivity Vol.XII
• /
• pp.23-23
• /
• 2002

• Restorative Dentistry and Endodontics
• /
• 제40권4호
• /
• pp.255-261
• /
• 2015

Objectives: The aim of this study was to evaluate the effect of three different drinks on the color parameters of four different restorative materials. Materials and Methods: Three different composites (Filtek Ultimate Universal Restorative, Filtek Ultimate Flowable, and Filtek Silorane, 3M ESPE) and a polyacid-modified composite resin material (Dyract XP, Dentsply DeTrey GmbH) were evaluated. Eighty-four disc-shaped specimens of 8 mm in diameter and 2 mm in thickness were prepared (n = 21 each). Color coordinates ($L^*a^*b^*$, ${\Delta}L^*$, ${\Delta}a^*$, ${\Delta}b^*$, and ${\Delta}E^*$) were measured using a $V{\dot{I}}TA$ Easyshade Compact ($V{\dot{I}}TA$ Zahnfabrik) after 24 hr of storage (baseline) and after 30 day of storage in three different beverages of black tea, Coca cola, or water (control) (n = 7). In each beverage, the specimens were stored three times a day, one hr each, for 30 day. The color changes (${\Delta}E$) were calculated and were analyzed by Kruskal-Wallis and Dunn multiple comparison test. Results: The color difference (${\Delta}E^*$) of the resin materials ranged between 1.31 and 15.28 after 30 day of immersion in the staining solutions. Dyract XP in Coca cola ($15.28{\pm}2.61$) and black tea ($12.22{\pm}2.73$) showed the highest mean ${\Delta}E^*$ value after 30 day, followed by Filtek Ultimate Universal Restorative ($5.99{\pm}1.25$) and Filtek Ultimate Flowable ($4.71{\pm}1.40$) in black tea (p < 0.05). Conclusions: The compomers displayed unacceptable color changes at the end of 30 day in all beverages. Among resin composites, the silorane based composite exhibited relatively good color stability than the others. Filtek Ultimate Universal Restorative and Filtek Flowable showed similar color changes in all beverages.

• Korean Journal of Radiology
• /
• 제19권6호
• /
• pp.1021-1030
• /
• 2018

Objective: We evaluated the effect of various patient characteristics and time-density curve (TDC)-factors on the test bolus-affected vessel enhancement on coronary computed tomography angiography (CCTA). We also assessed the value of generalized linear regression models (GLMs) for predicting enhancement on CCTA. Materials and Methods: We performed univariate and multivariate regression analysis to evaluate the effect of patient characteristics and to compare contrast enhancement per gram of iodine on test bolus (${\Delta}HUTEST$) and CCTA (${\Delta}HUCCTA$). We developed GLMs to predict ${\Delta}HUCCTA$. GLMs including independent variables were validated with 6-fold cross-validation using the correlation coefficient and Bland-Altman analysis. Results: In multivariate analysis, only total body weight (TBW) and ${\Delta}HUTEST$ maintained their independent predictive value (p < 0.001). In validation analysis, the highest correlation coefficient between ${\Delta}HUCCTA$ and the prediction values was seen in the GLM (r = 0.75), followed by TDC (r = 0.69) and TBW (r = 0.62). The lowest Bland-Altman limit of agreement was observed with GLM-3 (mean difference, $-0.0{\pm}5.1$ Hounsfield units/grams of iodine [HU/gI]; 95% confidence interval [CI], -10.1, 10.1), followed by ${\Delta}HUCCTA$ ($-0.0{\pm}5.9HU/gI$; 95% CI, -11.9, 11.9) and TBW ($1.1{\pm}6.2HU/gI$; 95% CI, -11.2, 13.4). Conclusion: We demonstrated that the patient's TBW and ${\Delta}HUTEST$ significantly affected contrast enhancement on CCTA images and that the combined use of clinical information and test bolus results is useful for predicting aortic enhancement.

• 한국의류산업학회지
• /
• 제11권4호
• /
• pp.672-677
• /
• 2009

To reduce the dependence of wool dyeing on the temperature several solvents with different properties and structures were added to the dye bath of C. I. Acid Yellow 42. Nearly the same total solubility parameters(${\delta}_t$) of solvents as those of wool fiber and hydrophobic part of the dyestuff were needed to increase disaggregation of dye molecules, loosening the wool fiber and wickabilty of dyeing solution; besides, the large surface tension(${\gamma}$) value of the solvents and the well balanced values of the three-component Hansen solubility parameters such as dispersion(${\delta}_d$), polar(${\delta}_p$), and hydrogen(${\delta}_h$) bonding parameters were required. Among the added solvents dimethyl phthalate(DMP) and acetophenone(AP) were satisfied with these conditions and worked the most successfully in the low temperature wool dyeing. Their effectiveness proven by the dyeing rate and the activation energy ($E_a$) of the dyeing was in the order of DMP > AP > DBE > CH > M >NONE. In conclusion the total solubility parameters(${\delta}_t$), the three-component Hansen parameters and the surface tension(${\gamma}$) of DMP and AP could be the guidelines to select suitable solvents for low temperature wool dyeing.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
• /
• pp.242-243
• /
• 2005

In this study, (La,Sr)$MnO_{3+\delta}$ powder used cathode material for SOFC was synthesized with precursor by GNP and the properties of powder, crystal phase, electric properties and deoxidization properties with precursor were investigated. The synthesis powder was prepared when oxidant/fuel mole and pH were 1 and 1, respectively and the synthesis powder was synthesized by GNP method using nitrate solution or oxide solution as precursor. Deoxidization peak of the nitrate solution was appeared lower temperature than the oxide solution, at $450^{\circ}C$. In this result, synthesis (La,Sr)$MnO_{3+\delta}$ powder using nitrate solution with Mn excess was suitable cathode material for SOFC due to had higher deoxidization properties. Also synthesis (La,Sr)$MnO_{3+\delta}$ powder according to precursor had difference electrical conductivity according to influence sintering density and crystal phase with precursor. Specially, the synthesis method and starting material had effect on deoxidization properties for SOFC.

• Bulletin of the Korean Chemical Society
• /
• 제14권4호
• /
• pp.515-519
• /
• 1993

The retention behavior of proteins was investigated by using hydrophobic interaction chromatography (HIC), comparing to the results obtained in reversed-phase chromatography (RPC) described in the previous paper. A SynChropak propyl column was employed with 0.05 M phosphate buffer (pH 7.0) containing sodium sulfate. Conformational changes were recognized by examining Z values as a function of sodium sulfate concentration over a range of temperature between 5 and 65$^{\circ}C$. Z values did not change significantly at the range of the temperature showing the consistent ${\Delta}H^{\circ}$ and ${\Delta}S^{\circ}$ values. The sign and the magnitude of ${\Delta}H^{\circ}$ and ${\Delta}S^{\circ}$ of proteins in HIC were compared with those obtained in RPC. The signs of ${\Delta}H^{\circ}$ and ${\Delta}S^{\circ}$ of proteins in HIC were all positive, while those of proteins in RPC were all negative. These results suggested that the retention of proteins in HIC and in RPC were entropy-driven and enthalpy-driven process, respectively. From the two different investigations, it was concluded that the retention mechanism of RPC and HIC was based on the same fundamental principle in which separation is dependent on hydrophobicity, but the retention behavior of the proteins in HIC is clearly different from that observed in RPC.

• 대한치과기공학회지
• /
• 제36권4호
• /
• pp.247-253
• /
• 2014

Purpose: The aim of this study was to evaluate the effect of colored zirconia with different coloring liquids. Methods: Total 30 specimens were prepared. Specimens were classified into 6 groups: IPS e.max Ceram(P), Uncolored zirconia(C), VITA In-Ceram$^{(R)}$2000 YZ LL1(L), Zirkonzahn coloring liquid(Z), Wieland coloring liquid(W), and Kuwotech coloring liquid(K). Four different types of zirconia coloring liquid, VITA In-Ceram$^{(R)}$ 2000 YZ LL1(VITA Zahnfabrik, Germany), Zirkonzahn coloring liquid(Zirkonzahn, Italy), Wieland coloring liquid(Wieland, Germany), Kuwotech coloring liquid(Kuwotech, Korea) were used to fabricate colored zirconia by using infiltrating method and then completely sintered. The color of the all specimens was measured using the spectrophotometer(CM-2600d, Konica Minolta, Japan) and expressed in terms of the 3-coordinated values(CIE $L^*a^*b^*$). Color differences were calculated using the equation $${\Delta}E^*=[({\Delta}L^*)^2+({\Delta}a^*)^2+({\Delta}b^*)^2]^{1/2}$$. Results: $L^*a^*b^*$ values of the colored zirconia were affected by the coloring liquids. The uncolored zirconia(C) group showed the highest $L^*$ value and zirkonzahn coloring liquid(Z) group showed the lowest $L^*$ value. Zirkonzahn coloring liquid(Z) showed the highest $a^*$ value and VITA In-Ceram 2000 YZ LL1(L) group showed the highest $b^*$ value. Generally, the color difference(${\Delta}E^*$) in all groups showed higher than 3.7 except between IPS e.max Ceram(P) and wieland coloring liquid(W) group. Conclusion: Within the limitations of this study, various coloring liquids influenced the $L^*$, $a^*$, and $b^*$ values of colored zirconia. IPS e.max Ceram(P) and wieland coloring liquid(W) group did not show clinically perceiving color difference.

• 치위생과학회지
• /
• 제13권4호
• /
• pp.434-439
• /
• 2013

본 연구는 시중에서 널리 사용되고 있는 구강양치액(Listerine, Hexamedin)을 선정하여 치면세균막의 제거 효과를 평가하기 위하여 20명의 실험참가자를 대상으로 반복적으로 동일한 대상자에게 적용하는 교차연구모형으로 구성하여 실험을 진행하였다. 치면세균막 측정은 최근에 주목받고 있는 QLF-D를 이용하여 치면세균막 제거효과를 정량적으로 평가하여 다음과 같은 결론을 도출하였다. 1. 이종의 구강양치액 모두 치면세균막이 감소하는 경향을 보였다. Listerine의 ${\Delta}R30$값과 ${\Delta}R70$값은 통계적으로 유의한 차이를 보였으며(p<0.05), Hexamedin는 경우에서는 SPS와 ${\Delta}R30$값은 통계적으로 유의한 차이를 보였다(p<0.05). 2. 측정결과를 종합한 결과 Hexamedin이 Listerine보다 치면세균막 제거 효과는 더 큰 폭으로 나타났다. 이상의 결과에서 구강양치액은 효과적인 치면세균막 조절 제재로 효과적임을 확인하였으며, QLF-D를 이용하여 치면세균막의 제거효과를 평가하는 새로운 방법이 시도되었다. 추후에 임상적용 시 유용한 치면세균막의 평가 도구로 활용할 수 있을 것으로 기대된다.