13-week Repeated Dose Toxicity and Genotoxicity Study of Tiglium Seed

Euna Kwon,Yun-Soon Kim,Seung-Hyun Kim,Ji-Ran You,Keun-Yong Park,Sang-Young Park,Ja-June Jang,Hyeon-Hoe Kim,Jin-ho Chung,Byeong-Cheol Kang(강병철) 한국실험동물학회 2005 한국실험동물학회 학술발표대회 논문집 Vol.2005 No.-

Toxicological Study of Safflower Seeds by Thirteen-Week Repeated Oral Administration in F344 Rats

Euna Kwon,Hyung-Jun Choi,Yun Soon Kim,Sang-Koo Lee,Kook-Hyun Lee,Jin Ho Chung,Myung-Whun Sung,Byeong-Cheol Kang 한국실험동물학회 2008 Laboratory Animal Research Vol.24 No.4

Safflower seeds which contains large amounts of conjugated linoleic acid and glyceride, are known to have effect on osteoporosis, bone fracture, and cholesterol metabolism. In this study, the 13-week repeated oral dose toxicity study of Safflower seeds was performed using F344 rats. In 14-day repeated dose study to determine the adequate dosage of safflower seeds administration, no other important changes were observed except statistically significant decreases in the mean absolute weights of the liver and the mean liver weight relative to body weight. It was dose-related finding at groups higher than 0.015 g/㎏ body weight (B.W.) in males and 0.045 g/㎏ B.W. in females. Based on preliminary test, safflower seeds was orally administered five times per week, weekday only to 5 groups of 6-week-old 10 male and 10 female F344 rats at dosage levels of 0.003, 0.016, 0.08, 0.4 and 2 g/㎏/day. The control group, also consisting of 10 males and 10 females, received the vehicle, 1% methylcellulose (MC), on a comparable regimen. One male and a female in the 0.4 g/㎏/day group, and a female in the 2 g/㎏/day group were found dead but the death could not be related to test article toxicity. No test article-related effect was observed on clinical signs and water consumption. For the 2 g/㎏/day males, there were significant decrease in body weight changes and food consumption from 10th week to study termination. The statistically significant decreases in the mean absolute weights of liver and the mean liver weight relative to body weight of the 0.003, 0.016 and 2 g/㎏/day group males and 0.003, 0.016 and 0.08 g/㎏/day females showed no dose related pattern and considered not to be test article related. There were no dose-related changes in hematology, biochemistry parameters, sperm morphology and vaginal cytology of all animals treated with safflower seeds. Gross and histopathological findings revealed no evidence of specific toxicity related to safflower seeds. These results suggest that no-observed adverse-effect level (NOAEL) of the test substance was considered to be 2 g/㎏/day for male and female rats under the conditions in this study.

Molecular Dynamics Simulation Study of a Carbon-Nanotube Oscillator in a Graphene-Nanoribbon Trench

Eunae Lee,Jeong Won Kang,Ki-Sub Kim,Oh Kuen Kwon 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.69 No.3

A graphene/carbon-nanotube (CNT) hybrid material can be useful in energy storage and nanoelectronic technologies. Here, we address a CNT oscillator encapsulated in a graphene-nanoribbon (GNR) trench as a novel design, and investigate its properties via classical molecular dynamics simulations. Because the energy barrier was very low while the CNT was encapsulated in the GNR trench, the CNT absorbed on the GNR surface could easily be encapsulated in the GNR trench. MD simulations showed that the CNT oscillator encapsulated in a GNR trench was compatible with simple CNT oscillators, so we anticipate that the CNT in the GNR trench could work as an oscillator. Thus, we can anticipate that the CNT encapsulated in a GNR trench can be applied to ultra-sensitive nanoelectromechanical oscillators and that this system has the possibility to be applied to relay-switching devices and to shuttle memories.

Development of Measurement Tool for Execution Function through Behavioral Data in Virtual Bookshelves Environment: focused on the Shifting Ability

Euna Park(박은아),Jieun Han(한지은),Hojin Choi(최호진),Prie Yannick,Toinon Vigier,Samuel Bluteau,Gyu Hyun Kwon(권규현) 대한인간공학회 2020 대한인간공학회 학술대회논문집 Vol.2020 No.10

Objective: This study aims to develop a measurement tool for the shifting ability as an Executive Functions (EF) in Virtual Environment (VE) based on the theory of embodied cognition. Background: Most of conventional EF measurement tools show an 18-20% difference between measured value through the questionnaires and ability of daily practices, which leads to dysfunctional problems in everyday life. Method: We designed a shifting measurement tool in VE. A measurement tool was developed by creating the scenario for organizing books on a bookshelf according to specific rules through an expert-based evaluation in a VE. (Color, Shape, Category) Using this measurement tool, we gained the tasks score data, duration, and the behavioral data of hand and head from 12 healthy adults(20-30s) and analyzed the data. Results: Using this Shifting measurement tool, we gain the behavioral data of hands and head, and tasks scores data from 12 participants. It is compared with the behavioral data of hand and head movement according to the task score. Conclusion: Findings of this study could be used to evaluate existing measurements and enhance a newly developed shifting measurement tool.

Nematicidal activity of Korean domestic plant extracts against pine wood nematode, Bursaphelenchus xylophilus

Eunae Kim,Junheon Kim,Seon-Mi Seo,Hwa-Jeong Yeom,Hye-Mi Park,Il-Kwon Park,Sang-Chul Shin 한국응용곤충학회 2010 한국응용곤충학회 학술대회논문집 Vol.2010 No.10

In this study, we investigated the nematicidal activities of 102 Korean domestic plant extracts which have not been tested before against B. xylophilus. Nematicidal activity of plant extracts were varied according to plant species and extraction part. Among 102 plant extracts, 42 plant extracts in 22 families showed >50% nematicidal activity against pine wood nematode at 10 mg/mL concentration. Among 31 wood extracts, very strong nematicidal activity (100%) was produced from extract of Neolitsea aciculate, Prunus sargentii and Rhus chinensis at 10 mg/mL concentration. Extracts from Camellia japonica, Carpinus cordata, Daphniphyllum macropodum, Eucommia ulmoides, Ilex cornuta, Myrica rubra, Vaccinium bracteatum, and Zelkova serrata showed strong nematicidal activities (80-99%). The other samples exhibited activities <80%. In a test with leaf extracts, strong neamticidal activity was observed in extract of Machius japonica (100%) followed by Picea koraiensis (99.4%), Meliosma oldhamii (82.7%), and Zelkova serrata (81%). The other 37 plant species revealed <80% mortality. Strong nematicidal activity (>80%) was observed from bark extract of Carpinus cordata, Comus kousa, Cryptomeria japonica, Machius japonica, Quercus glauca and Zelkova serrata. Nematicidal activity of other 19 bark extracts was less than 80%. Twig extract of Smilax china and fruit extract of Forsythia koreana showed 86.6 and 81.4% nematicidal activity at 10 mg/mL concentration, respectively.

Development of Measurement Tool for Execution Function through Behavioral Data in Virtual Bookshelves Environment: focused on the Shifting Ability

Euna Park(박은아),Jieun Han(한지은),Hojin Choi(최호진),Prie Yannick,Toinon Vigier,Samuel Bluteau,Gyu Hyun Kwon(권규현) 대한인간공학회 2020 대한인간공학회 학술대회논문집 Vol.2020 No.10

Objective: This study aims to develop a measurement tool for the shifting ability as an Executive Functions (EF) in Virtual Environment (VE) based on the theory of embodied cognition. Background: Most of conventional EF measurement tools show an 18-20% difference between measured value through the questionnaires and ability of daily practices, which leads to dysfunctional problems in everyday life. Method: We designed a shifting measurement tool in VE. A measurement tool was developed by creating the scenario for organizing books on a bookshelf according to specific rules through an expert-based evaluation in a VE. (Color, Shape, Category) Using this measurement tool, we gained the tasks score data, duration, and the behavioral data of hand and head from 12 healthy adults(20-30s) and analyzed the data. Results: Using this Shifting measurement tool, we gain the behavioral data of hands and head, and tasks scores data from 12 participants. It is compared with the behavioral data of hand and head movement according to the task score. Conclusion: Findings of this study could be used to evaluate existing measurements and enhance a newly developed shifting measurement tool.

Economic and environmental sustainability and public perceptions of rooftop farm versus extensive garden

Kim, Euna,Jung, Jihyeun,Hapsari, Gita,Kang, Seju,Kim, Kibeum,Yoon, Saerom,Lee, Miran,Han, Mooyoung,Choi, Yongju,Choe, Jong Kwon Elsevier 2018 Building and environment Vol.146 No.-

<P><B>Abstract</B></P> <P>Green roofs have become popular in urban areas as a solution to restore green space in cities and mitigate urban problems. In this study, the economic and environmental sustainability of using green roofs for rooftop agriculture (i.e., roof farms) is evaluated and compared with that of using green roofs as extensive gardens of flowers and non-edible plants with low maintenance (i.e., roof gardens) based on these two green roofs that were installed and operated for over five years in a university building in Seoul, Korea. The life cycle cost analysis results show that the total cost of the roof garden is 38.9% lower than the flat roof whereas the total cost of the roof farm is 68.3% higher than the roof garden. The environmental impacts of both the roof garden and farm were 2.4–35 times as high as those of the flat roof. The need to frequently replenish the lightweight soil over its lifetime was the main contributor to both the economic cost and environmental impacts of the roof farm, suggesting a need to develop cost-effective and environmentally benign lightweight soil materials. A survey was also conducted to investigate public preferences and perceptions of these two green roof options. Over 80% of the respondents expressed the necessity for green roofs in urban areas, and 79.3% preferred roof gardens over farms. Our results show that roof farms have several merits in urban areas, especially social benefits, but future research should focus on improving their economic and environmental sustainability.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Use of green roofs as rooftop farm versus extensive garden is evaluated. </LI> <LI> The life cycle cost of roof garden is lower than flat roof, but roof farm was higher. </LI> <LI> Lightweight soil is the main economic and environmental contributor of roof farm. </LI> <LI> A survey study showed that 79.3% of respondents preferred roof gardens over farms. </LI> <LI> Economic and environmental sustainability of roof farms should be further improved. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Block Copolymer Directed One-Pot Simple Synthesisof L1₀-Phase FePt Nanoparticles inside Ordered MesoporousAluminosilicate/Carbon Composites

Kang, Eunae,Jung, Hyunok,Park, Je-Geun,Kwon, Seungchul,Shim, Jongmin,Sai, Hiroaki,Wiesner, Ulich,Kim, Jin Kon,Lee, Jinwoo American Chemical Society 2011 ACS NANO Vol.5 No.2

<P>A 'one-pot' synthetic method was developed to produce L1(0)-phase FePt nanopartides in ordered mesostructured aluminosilicate/carbon composites using polyisoprene-block-poly(ethylene oxide) (Pl-b-PEO) as a structure-directing agent. Pl-b-PEO block copolymers with aluminosilicate sols are self-assembled with a hydrophobic iron precursor (dimethylaminomethylferrocene) and a hydrophobic platinum precursor (dimethyl(1,5-cyclooctadiene)platinum(II)) to obtain mesostructured composites. The as-synthesized material was heat-treated to 800 degrees C under an Ar/H-2 mixture (5% v/v), resulting in the formation of fct FePt nanocrystals encapsulated in ordered mesopores. By changing the quantities of the Fe and Pt precursors in the composite materials, the average particle size of the resulting fct FePt, estimated using the Debye-Scherer equation with X-ray diffraction patterns, can be easily controlled to be 2.6-10.4 nm. Using this simple synthetic method, we can extend the size of directly synthesized fct FePt up to similar to 10 nm, which cannot be achieved directly in the colloidal synthetic method. All fct FePt nanoparticles show hysteresis behavior at room temperature, which indicates that ferromagnetic particles are obtained inside mesostructued channels. Well-isolated, similar to 10 nm fct FePt have a coercivity of 1100 Oe at 300 K. This coercivity value is higher than values of fct FePt nanoparticles synthesized through the tedious hard template method by employing SBA-15 as a host material. The coercivity value for FePt-1 (2.6 nm) at 5 K is as high as 11 900 Oe, which is one of the largest values reported for FePt nanoparticles, or any other magnetic nanoparticles. The fct FePt nanoparticles also showed exchange-bias behavior.</P>

Effects of Edta on the Electronic Properties of Passive Film Formed on Fe-20Cr In pH 8.5 Buffer Solution

Cho, EunAe,Kwon, HyukSang,Bernard, Frederic 한국부식방식학회 2003 Corrosion Science and Technology Vol.2 No.4

The electronic properties of the passive film formed on Fe-20Cr ferritic stainless steel in pH 8.5 buffer solution containing 0.05 M EDTA (ethylene diammine tetraacetic acid) were examined by the photocurrent measurements and Mott-Schottky analysis for the film. XPS depth profile for the film demonstrated that Cr content in the outermost layer of the passive film was higher in the solution with EDTA than that in the solution without EDTA, due to selective dissolution of Fe by EDTA. In the solution with EDTA, the passive film showed characteristics of an amorphous or highly disordered n-type semiconductor. The band gap energies of the passive film are estimated to be ∼ 3.0 eV, irrespective of film formation potential from 0 to 700 mV_(SCE) and of presence of EDTA. However, the donor density of the passive film formed in the solution with EDTA is much higher than that formed in the solution without EDTA, due to an increase in oxygen vacancy resulted ti-om the dissolution of Fe-oxide in the outermost layer of the passive film. These results support the proposed model that the passive film formed on Fe-20Cr in pH 8.5 buffer solution mainly consists of Cr-substituted γ-Fe₂0₃.

Mass rearing of the box tree pyralid, Glyphodes perspectalis, with artificial diet and sex pheromone analysis

Il-Kwon Park,Junheon Kim,Sang-Chul Shin,Sung-Woong Kim,Eunae Kim,Seon-Mi Seo,Hwa-Jung Yeom 한국응용곤충학회 2011 한국응용곤충학회 학술대회논문집 Vol.2011 No.05

In this study, we reared box tree pyralid, Glyphodes perspectalis, with artificial diet and identified sex pheromone. Insect F-II and leaf of box tree were used to make artificial diet. Box tree pyralid, Glyphodes perspectalis, is the most serious pest of box tree in Korea, and was recently introduced into Europe. The pheromone components of this moth have been identified as (Z)-11-hexadecenal (Z11-16:Ald), (E)-11-hexadecenal (E11-16:Ald), and (Z)-11-hexadecenol (Z-11- 16:OH) in Japan. In this study, we identified pheromone components of this species by using GC and GC-MS. Three same components, such as (Z)-11- hexadecenal (Z11-16:Ald), (E)-11-hexdecenal (E11-16:Ald), and (Z)-11-hexadecenol (Z-11-16:OH) were also indentified in Korean population, but there was a little difference in ratios. The ratios of these three compounds of Japanese population and Korean population were 5:1.25:1, and 5:0.96:0.2, respectively. The ratios of Z and E-11-hexadecenal were similar, but the ratio of (Z)-11-hexadecenol was lower compared to Japanese population. In field bioassay, (Z)-11-hexadecenal or (E)-11-hexadecenal alone was not attractive to males, but the mixture of Z11-16:Ald and E11-16:Ald was attractive to males. The most effective ratios of Z11-16:Ald and E11-16:Ald was 5:1. Other ratios such as 1:1 and 1:5 (Z:E) was not attractive to males. The attractiveness of Z:11-16:OH will be tested in near future.