• Title/Summary/Keyword: Mixed solution

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Comparison and evaluation of 89Zr-labeled trastuzumab and Thio-trastuzumab : a potential immuno-PET probe for HER2-positive carcinomas

  • Un Chol Shin;Seoku Bae;Suk-man Kim;Min-Woo Lee;Han Sang Jin;Hyun Park;Kyo Chul Lee;Jung Young Kim;Ji Woong Lee
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.7 no.2
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    • pp.105-111
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    • 2021
  • 89Zr is a positron-emitting radioisotope, which has known as well-suited radioisotope for use in a monoclonal antibody-based imaging agent for immuno-PET. The purpose of this study was to quantitatively evaluate the diagnostic ability of general trastuzumab and thio-trastuzumab as HER2 positive receptors based on Df hexadentate iron chelator. Desferrioxamine-p-SCN (Df-Bz-NCS) and desferroixamine-maleimide (Df-Mal) were purchased from Macrocyclics (Dallas, TX, USA). The trastuzumab was purchased from Roche (Schweiz), and thio-trastuzumab was obtained from professor Hyo-Jeong Hong group (Kangwon National University). The radioisotope 89Zr was produced by domestic purification system and KIRAMS using medical cyclotron (50 MeV, Scantronix). The conjugates of Df-trastuzumab and Df-thio-trastuzumab were prepared with Df-Bz-NCS and Df-Mal under basic aqueous solution (pH 8-9) at room temperature, respectively. The conjugates purified by PD-10 column were mixed with dried 89Zr chloride. 89Zr-labeled conjugates were purified and concentrated by Amicon ultra centrifugal filter. The preparation step and time of 89Zr-labeled conjugates was shorted as 4 steps within 2 hours. 89Zr-labeled conjugates showed the highly radiochemical purity of over 98%, and were very stable until 7 days by the analysis of radio-ITLC method. Each radio-labeled conjugates were also exhibited the highly stability in both PBS buffer and mouse serum. Immuno-PET imaging of 89Zr-labeled conjugates in mice bearing gastric cancer xenograft tumors with HER2 expression showed high tumor uptake in the NCI-N87 HER2-expressing. However, 89Zr-Df-Mal-thio-trastuzumab showed a relatively lower tumor-to-background ratio than 89Zr-Df-Bz-trastuzumab, as well as whole-body distribution. In the results, 89Zr-Df-Bz-trastuzumab was evaluated to have a relatively higher HER2 diagnostic ability than 89Zr-Df-Mal-thio-trastuzumab.

High Temperature Application of Iron Removal Chemical Cleaning Solvent in the Secondary Side of Nuclear Steam Generators (증기발생기 2차측 제철화학세정액의 고온적용)

  • Hur, D.H.;Lee, E.H.;Chung, H.S.;Kim, U.C.
    • Nuclear Engineering and Technology
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    • v.26 no.1
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    • pp.140-148
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    • 1994
  • A qualification test was performed for the iron removal chemical cleaning of the secondary side of nuclear steam generators at the selected temperature, 1$25^{\circ}C$, higher than the standard application temperature, 93$^{\circ}C$. The field cleaning condition for a nuclear unit was tested in a bench scale test loop including a SUS 316 stainless steel autoclave with one gallon capacity as a test vessel. The kinetics of sludge dissolution, corrosion of the secondary side materials and change of solvent chemistry were monitored. Test results indicated that more thorough cleaning was accomplished in less than half of the cleaning time required at 93$^{\circ}C$. And the total corrosions of the secondary side materials were found to be less than the values at 93$^{\circ}C$. While the solvent is recirculated and heated by an external chemical cleaning equipment for the conventional 93$^{\circ}C$ process, the secondary side is heated by the lateral heat of the primary coolant without the recirculation of the cleaning solution, and the solvent is mixed by vigorous boiling induced by periodic ventilation for the high temperature process. The requirement that the reactor coolant pumps should be running during the cleaning operation is the major disadvantage of the high temperature process which also should be considered when chemical cleaning is planned for steam generators under operation.

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Separation of Antioxidants and Glucose from Grape Skin Extract Using Polyethylene Glycol and Sodium Citrate (폴리에틸렌글리콜과 구연산 나트륨을 이용하여 포도껍질 추출물에서 항산화물질과 포도당 분리)

  • Eun Min Shin;Yeong Eun Joo;Su Min Jung;Jaechan Suh;Chang-Joon Kim
    • Clean Technology
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    • v.29 no.2
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    • pp.109-117
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    • 2023
  • The purpose of this study is to develop a method for separating antioxidants and sugars from grape skin extract. The extract was first mixed with a variety of organic solvents to investigate whether the separation was feasible. When employing acetone, ethanol, dimethylsulfoxide, or dimethylformamide, the organic solvent-extract combination formed a single phase. However, when benzene, ethyl acetate, or n-hexane was added to the extract, the mixture separated into an organic and an aqueous phase and the pigments remained in the aqueous phase. On the other hand, when polyethylene glycol-2,000 (PEG-2000) and sodium citrate were added to the extract, the mixture was separated into three layers, with the majority of the flavonoids migrating to the top layer and 53% of the extract's glucose migrating to the bottom layer. The top layer had significant antioxidant activity, whereas the bottom layer showed no antioxidant activity. The glucose recovery in the bottom layer increased as the molecular weight of PEG increased and the highest recovery (67%) was observed when PEG-8,000 was added. The highest flavonoid separation was observed with PEG-2,000, followed by PEG-8,000 and PEG-400. The flavonoid separation when PEG-2,000 was added resulted in a flavonoid recovery of 48% and 0.2% from the top and bottom layers, respectively. Examining the effect of the separated solution using the agar disc diffusion method on yeast cell growth confirmed that the addition of the extract, the top, and the bottom layer did not inhibit cell growth.

Effect of Immersion and High Temperature on Shear Strength of Cemented Sand (수침 및 고온이 고결모래의 전단강도에 미치는 영향)

  • Moon, Hong Duk;Hwang, Keum-Bee;Kim, Tae-hun;Park, Sung-Sik
    • Journal of the Korean Geotechnical Society
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    • v.39 no.7
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    • pp.17-30
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    • 2023
  • This study investigates the impact of water immersion and high temperature on the shear strength of cemented sand through direct shear tests. Standard Jumunjin sand was used and cemented with binders, such as ultra-rapid hardening cement and an epoxy aqueous solution. The binder was mixed at concentrations of 4%, 8%, or 12%. Subsequently, cylindrical cemented specimens with a diameter of 64 mm and height of 25 mm were produced using compaction. The curing period was three days, and the specimens were cured under dry air, immersion, and heating conditions. The heating condition involved subjecting the immersed specimens to a microwave oven three times for three minutes to achieve an internal temperature of approximately 90℃. Regardless of the binder type, the cohesion of the cemented sand increased with higher binder content, whereas the internal friction angle exhibited a slight increase or decrease. Compared with ultra-rapid hardening cemented sand, epoxy-cemented sand displayed an average cohesion that was five times higher and an internal friction angle that was 10° higher. Overall, irrespective of binder type, the shear strength decreased during water immersion and increased during heating. Notably, the epoxy-cemented sand exhibited a three-fold increase in cohesion and a more than 20° increase in the internal friction angle during heating.

A sensitive analytical method for determination of 3-monochloropropane-1,2-diol and 1,3-dichloropropan-2-ol in various foods by gas chromatography with mass spectrometer (가스크로마토그래피/질량분석기를 이용한 식품 중 클로로프로판올 화합물 분석)

  • Kim, Eunju;Park, Sungkug;Choi, Dongmi
    • Analytical Science and Technology
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    • v.21 no.6
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    • pp.543-552
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    • 2008
  • This paper described the relatively sensitive and simultaneous analytical method for 3-monochloropropane-1,2-diol (3-MCDP, $C_3H_7ClO_2$, MW. 110) as well as 1,3-dichloropropan-2-ol (1,3-DCP, $C_3H_6Cl_2O$, MW. 128) in various foods. Food samples were homogenized in 5M NaCl solution, mixed with aluminum oxide and eluted with dichloromethane. The extracted chloropropanols were concentrated by rotary evaporator and $N_2$ blow serially were derivatized with HFBA (Heptafluorobutyric anhydride, $C_8F_{14}O_3$, MW. 410) and were determined by GC/MS using isotope dilution method. The characteristic molecular ions at m/z 253, 275, 289, 291, and 453 for HFBA derivatives of 3-MCPD (MW. 502) and 110, 275, and 277 for HFBA derivatives of 1,3-DCP (MW. 325) were chosen in selected ion mode. The method validation data showed sufficiently good properties of LOD (0.003 mg/kg), LOQ (0.010 mg/kg), linearity ($R^2{\geq}0.999$ at 0.010~1.000 mg/kg), and recovery rate (${\approx}97%$). The levels of chloropropanols in soy sauce, sauces, processed meat products, fishery products, and seasonings (n=56/157) determined by the presented method were 0.0~0.3 mg/kg.

The analysis for the HCl modification effect and formation of TiO2 on activated carbon fiber surface (활성탄소섬유 표면의 염산처리효과와 TiO2 형성에 관한 분석)

  • Oh, Won-Chun;Han, Sang-Bum;Bae, Jang-Soon
    • Analytical Science and Technology
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    • v.20 no.4
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    • pp.279-288
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    • 2007
  • We have studied a method for the preparation of $ACF/TiO_2$ composites involving the penetrationof titanium n-butoxide (TNB) solution into activated carbon fiber. It was focused on the characterization of $TiO_2$ formed in prorous carbon was which increased with surface functional groups by hydrochloric acid treatment. The conversion of TNB to $TiO_2$ for the acid treatment effect must be important for the preparationof $ACF/TiO_2$ composites. From the characterization of surface properties, both the BET surface area and the total pore volume decreased as the distribution of $TiO_2$ on the activated carbon fiber surfaces after acid treatments.The changes in XRD pattern showed the typical anatase type on $ACF/TiO_2$ composite for the sample named FT, FT1 and FT2 treated with 0.05, 0.1 and 0.5 M, respectively. However, XRD patern of FT3 treated with 0.5M showed mixed amatase-rutile structure. According to the results of SEM micrographs, the titanium complexe particles were irregularly distributed around carbon. And some large clusters were found when an amount of acid treatment increased. The EDX results of $ACF/TiO_2$ composites showed the presence of C, O and P with strong Ti peaks. Finally, the excellent photocatalytic activity of the $ACF/TiO_2$ composites between relative concentration($c/c_o$) of MB (methylene blue) and UV irradiation time could be attributed to the both effects between photocatalysis of the formation of titania complexes and adsorptivity of the activated carbon fiber.

Traffic Impacts of Transit-oriented Urban Regeneration (TOD형 도시재생사업의 교통영향 분석)

  • Hwang, Kee Yeon;Cho, Yong Hak
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.4D
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    • pp.469-476
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    • 2008
  • Recently, TOD gains popularity as a traffic solution measure of high density urban regeneration projects. The purpose of this study is to investigate traffic impacts of high density TOD projects, and to identify the issues to be resolved. For a case study, it chooses Gangnamgucheong station in Gangnam area served by two subway lines, and designates 400m radius from the station as a site for high-density development. The MOEs chosen for this study is traffic volume, time, distance, speed, and mode share. The SECOM model is adopted for traffic simulation. The analysis results show that high-density TOD is an effective tool for traffic improvement even with only one station area being implemented. It is found that the traffic volume increases near the station in nature where high-density development occurs, but it declines overall in the rest of Gangam area. The total travel time and distance of passenger vehicles decline, meaning that the traffic condition becomes better than before. With regulation on parking supply, the improvement becomes more vivid. In terms of the changes of traffic speed, both alternatives show 4.1% increase in speed, but the difference between alternatives is not quite noticeable because of the induced vehicle demand driven to the streets with improved traffic condition. The mode share changes occur for the benefit of subway ridership, because the study station is equipped with two subway line services. When mixed with parking supply restriction, the impact becomes clearer.

Assessment of the Utility of Remote Sensing Techniques for Monitoring Compliance with Direct Payment Programs (직불제 이행점검 모니터링을 위한 원격탐사 기법 활용성 평가)

  • Hoyong Ahn;Jae-Hyun Ryu;Kyungdo Lee
    • Korean Journal of Remote Sensing
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    • v.39 no.6_1
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    • pp.1467-1475
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    • 2023
  • The public-interest direct payment program involves providing direct payments to agricultural producers and rural residents through public funds, premised on performing public functions such as environmental conservation, stable food supply, and maintaining rural communities via agricultural activities. Scientific estimation of crop cultivation areas and production levels is crucial for formulating agricultural policies linked to regulating food supply, which increasingly impacts the national economy. Conducting comprehensive on-site inspections for compliance monitoring of direct payment programs has shown very low efficiency in relation to budget and time. The expansion of areas subject to compliance monitoring and various challenges in on-site inspections necessitate streamlining current monitoring methods and devising effective strategies. As a solution, the application of Remote Sensing technology and spatial information utilization, allowing swift acquisition of necessary information for policies without overall on-site visits, is being discussed as an efficient compliance monitoring method. Therefore, this study evaluated the potential use of remote sensing for improving operational efficiency in monitoring compliance with public-interest direct payment programs. Using satellite images during farming seasons in Gimje and Hapcheon, vegetation indices and spatial variations were utilized to identify cultivated areas, presence of mixed crops, validated against on-site inspection data.

Effect of Ethanol Fractionation of Lignin on the Physicochemical Properties of Lignin-Based Polyurethane Film

  • Sungwook WON;Junsik BANG;Sang-Woo PARK;Jungkyu KIM;Minjung JUNG;Seungoh JUNG;Heecheol YUN;Hwanmyeong YEO;In-Gyu CHOI;Hyo Won KWAK
    • Journal of the Korean Wood Science and Technology
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    • v.52 no.3
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    • pp.221-233
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    • 2024
  • Lignin, a prominent constituent of woody biomass, is abundant in nature, cost-effective, and contains various functional groups, including hydroxyl groups. Owing to these characteristics, they have the potential to replace petroleum-based polyols in the polyurethane industry, offering a solution to environmental problems linked to resource depletion and CO2 emissions. However, the structural complexity and low reactivity of lignin present challenges for its direct application in polyurethane materials. In this study, Kraft lignin (KL), a representative technical lignin, was fractionated with ethanol, an eco-friendly solvent, and mixed with conventional polyols in varying proportions to produce polyurethane films. The results of ethanol fractionation showed that the polydispersity of ethanol-soluble lignin (ESL) decreased from 3.71 to 2.72 and the hydroxyl content of ESL increased from 4.20 mmol/g to 5.49 mmol/g. Consequently, the polyurethane prepared by adding ESL was superior to the KL-based film, exhibiting improved miscibility with petrochemical-based polyols and reactivity with isocyanate groups. Consequently, the films using ESL as the polyol exhibited reduced shrinkage and a more uniform structure. Optical microscope and scanning electron microscope observations confirmed that lignin aggregation was lower in polyurethane with ESL than in that with KL. When the hydrophobicity of the samples was measured using the water contact angle, the addition of ESL resulted in higher hydrophobicity. In addition, as the amount of ESL added increased, an increase of 7.4% in the residual char was observed, and a 4.04% increase in Tmax the thermal stability of the produced polyurethane was effectively improved.

Protective Effect of Nitroglycerin on the Ischemia-Reperfusion Model of the Isolated Rat Lung (흰쥐의 분리 폐장 관류 모델에서 Nitroglycerin의 폐장 보존 효과)

  • Jheon, Sang-Hoon;Lee, Sub;Lee, Jong-Hoon;Son, Bok-Kyoung;Cho, Gong-Rae;Chung, Jin-Yong;Cho, Soung-Kyung;Kim, Bong-Il;Lee, Young-Man;Choh, Joong-Haeng
    • Journal of Chest Surgery
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    • v.36 no.12
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    • pp.894-903
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    • 2003
  • Protection against ischemia-reperfusion injury is crucial for successful transplantation of the lung. It has been known that nitric oxide has many favorable effects on the donor lungs but at the same time, has some potential side effects of cytotoxicity. In this regards, we investigated whether the administration of nitroglycerin could decrease ischemia-reperfusion injury in isolated rat lung reperfusion model for the confirmation of the effect of nitroglycerin, a donor of nitric oxide, on lung transplantation. Material and Method: 35 Sprague-Dawley species male white rats were used for this experiment. For nitroglycerin group (n=18), nitroglycerin was administered intravenously followed by mixed in flushing solution for preservation. As a control group (n=17), we used the same amount of normal saline. To evaluate the effect of nitroglycerin on the lung, heart-lung block was obtained, weighed and stored in University of Wisconsin Solution at 1$0^{\circ}C$ for 24 hours. In each group of the isolated lungs, reperfusion was carried out with Krebs-Hensleit-diluted human blood for 60 minutes. As parameters of the state of the isolated lung, peak inspiratory and pulmonary arterial pressures were continuously recorded. Oxygen and carbon dioxide tension of reperfusing blood were measured before and after 30, 60 minutes of reperfusion. After sixty minutes of reperfusion, protein content in bronchoalveolar lavage fluid was measured also for the evaluation of the degree of alveolar flooding. Lung myeloperoxidase activity was determined to verify the accumulation of neutrophils. Results: Although statistically significant differences were not noted in peak inspiratory and pulmonary arterial pressure between control and nitroglycerin group, latter group showed lowering tendency of pulmonary arterial pressure during the entire reperfusion period. Oxygen tension was higher (p<0.05) in nitroglycerin group compared with that of the control group, in contrast, there were no differences in carbon dioxide tension, protein content in bronchoalveolar lavage fluid and myeloperoxidase activity between the groups. In the examination of ultrastructural changes, nitroglycerin denoted the protective effect on the pulmonary architecture compared with that of control group. Conclusion: Collectively, on the bases of these experimental results, prior treatment of donor lung with nitroglycerin could result in better preservation of the lung. Consequently, these nitroglycerin preserved lungs are thought to be more suitable for successful transplantation of the lung.