• Title/Summary/Keyword: Analytical

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Inhibitory Effects of Ethanolic Extracts from Aster glehni on Xanthine Oxidase and Content Determination of Bioactive Components Using HPLC-UV (섬쑥부쟁이 에탄올 추출물의 잔틴산화효소 저해 효능 및 HPLC-UV를 이용한 유효성분의 함량 분석)

  • Kang, Dong Hyeon;Han, Eun Hye;Jin, Changbae;Kim, Hyoung Ja
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.11
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    • pp.1610-1616
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    • 2016
  • This study aimed to establish an optimal extraction process and high performance liquid chromatography-ultraviolet (HPLC-UV) analytical method for determination of 3,5-dicaffeoylquinic acid (3,5-DCQA) as a part of materials standardization for the development of a xanthine oxidase inhibitor as a health functional food. The quantitative determination method of 3,5-DCQA as a marker compound was optimized by HPLC analysis using a Luna RP-18 column, and the correlation coefficient for the calibration curve showed good linearity of more than 0.9999 using a gradient eluent of water (1% acetic acid) and methanol as the mobile phase at a flow rate of 1.0 mL/min and a detection wavelength of 320 nm. The HPLC-UV method was applied successfully to quantification of the marker compound (3,5-DCQA) in Aster glehni extracts after validation of the method with linearity, accuracy, and precision. Ethanolic extracts of A. glehni (AGEs) were evaluated by reflux extraction at 70 and $80^{\circ}C$ with 30, 50, 70, and 80% ethanol for 3, 4, 5, and 6 h, respectively. Among AGEs, 70% AGE at $70^{\circ}C$ showed the highest content of 3,5-DCQA of $52.59{\pm}3.45mg/100g$ A. glehni. Furthermore, AGEs were analyzed for their inhibitory activities on uric acid production by the xanthine/xanthine oxidase system. The 70% AGE at $70^{\circ}C$ showed the most potent inhibitory activity with $IC_{50}$ values of $77.01{\pm}3.13{\sim}89.96{\pm}3.08{\mu}g/mL$. The results suggest that standardization of 3,5-DCQA in AGEs using HPLC-UV analysis would be an acceptable method for the development of health functional foods.

Safety Assessment of Estimated Daily Intakes of Antioxidants in Korean Using Dietary Survey Approach and Food Supply Survey Approach (식이를 통한 평가방법과 공급량 평가방법을 이용한 산화방지제 일일 추정 섭취량 안전성 평가)

  • Suh, Hee-Jae;Choi, Sung-Hee
    • Korean Journal of Food Science and Technology
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    • v.42 no.6
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    • pp.762-767
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    • 2010
  • This study evaluated daily intakes of BHT, BHA, and TBHQ in Korean. The daily intakes were estimated using both a dietary survey approach and food supply survey approach. In the dietary survey approach, individual dietary intake data from the Korea National Health and Nutrition Survey in 2005, as well as analytical results of BHT in 131 samples, BHA in 134 samples, and TBHQ in 104 samples, were used to assess daily intakes of the antioxidants. In the food supply survey approach, both total production amounts of BHT, BHA and TBHQ and maximum permitted levels of the antioxidants were used to calculate daily intakes. In the dietary survey results, the average daily intakes of BHT, BHA and TBHQ were 0.8, 0.5, and 0.3 ${\mu}g$/kg body weight/day, respectively, and below 0.2% of the ADI (acceptable daily intake) set by JECFA (Joint FAO/WHO Expert committee on Food Additives). In the food supply survey approach, the average daily intakes of BHT, BHA,and TBHQ were all 0.3 mg/kg body weight/day. The ratios of ADI were 97, 60, and 40%, respectively. According to these results, daily intakes of BHT, BHA, and TBHQ in Korean are lower than the ADI.

Establishment of a Method for the Analysis of Diarrhetic Shellfish Poisoning by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS를 이용한 설사성패류독소의 분석조건 확립)

  • Lee, Ka-Jeong;Suzuki, Toshiyuki;Kim, Poong-Ho;Oh, Eun-Gyoung;Song, Ki-Cheol;Kim, Ji-Hoe
    • Korean Journal of Food Science and Technology
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    • v.41 no.4
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    • pp.458-463
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    • 2009
  • To establish and validate a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the rapid and accurate quantitation of diarrhetic shellfish poisoning (DSP) toxins, we compared the results from different mobile phases and columns used for their analysis and collision energies for MS/MS experiments. Clear peaks of okadaic acid (OA) and dinophysistoxin-1 (DTX1) were obtained by using a mobile phase comprising aqueous acetonitrile containing 2 mM ammonium formate and 50 mM formic acid. The collision energies were optimized to facilitate the most sensitive detection for each toxin, namely, OA, DTX1, pectenotoxin-2 (PTX2), or yessotoxin (YTX). Further, the maximum ion response was obtained at a collision energy of 48 V for OA and DTX1. We compared the analytical performance of $C_8$ and $C_{18}$ columns. A wide range of toxins namely, OA, DTX1, PTX2, and YTX, except DTX3, were detected by both the columns. Although DTX3 was only detected by the $C_8$ column, we found that the $C_{18}$ column was also suitable for the quantitation of OA and DTX1 the toxins responsible for inducing diarrhea. The limit of detection of OA and DTX1 by the established LC-MS/MS conditions was 1 ng/g, and the limit of quantitation of the toxins under the same conditions was 3 ng/g. The process efficiencies were 91-118% for oysters (Crassostrea gigas) and 96-117% for mussels (Mytilus galloprovincialis) further, we observed no significant effect of matrix during the ionization process in LC-MS/MS. The comparison between mouse bioassay (MBA) and LC-MS/MS yielded varying results because low concentrations of OA and DTX1 were detected by LC-MS/MS in some shellfish samples, which provided positive results on MBA for DSP. The analysis time required by MBA for DSP analysis can be reduced by LC-MS/MS.

Site Selection of Wildlife Passage for Leopard Cat in Urban Area using Space Syntax (공간구문론을 이용한 도시 내 삵 이동통로 적지선정)

  • Park, Jong-Jun;Woo, Dong-Geol;Oh, Dae-Hyun;Park, Chong-Hwa
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.1
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    • pp.92-99
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    • 2012
  • Many wildlife habitats have been destroyed and fragmented during the rapid industrialization and urbanization process in Korea. It is essential to connect these fragmented habitats to reduce road-kill of many types of endangered urban wildlife. The site selection for wildlife passages must take into account the behavior of the wildlife species for safe crossing utilizing many artificial barriers in urban areas. This study attempted to identify potential wildlife passage sites for the endangered and protected leopard cats of Gangseo Ecological Park in Seoul, Korea. A space syntax analysis, an analytical technique to objectively evaluate the spatial configurations related to passage selection, found that the integration value represents the accessibility and connectivity of spaces. In this paper, this means that the bigger the integration value, the more frequently the leopard cat passes through. The leopard cats were captured and radio-tracked for 72 hours once a month from March to June of 2009. The ArcGIS and Animal Movement of Hawth Tools were used to analyze the home range and movement paths, and Axwoman 4.0 was used to analyze space syntax. The daily average movement distance was $2.099{\pm}1.08km$. During the survey period, the leopard cats crossed over an urban expressway more than 20 times, running the risk of road-kill. The range of global integration values was 0.458~1.834, while that of the local integration was 0.210~6.061. Five sites that met across the leopard cats' movement routes and roads were selected to measure the local and global integrate values. Among these sites, the higher the integration value, the higher the road-kill possibility. Thus, two of five sites with high global and local integration values were suggested as potential wildlife passage sites for the leopard cats. Now, three tunnel passages are under construction at the suggested sites for which local integration value was highest (LI=4.369). Further studies are scheduled to verify these potential sites as suitable wildlife passages.

Validation of the Proximity of Clothing to Self Scale for Older Persons (의복의 자아 근접성 척도 검증 - 노년층을 대상으로 -)

  • Lee, Young-A;Sontag, M. Suzanne
    • Journal of the Korean Society of Clothing and Textiles
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    • v.31 no.6 s.165
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    • pp.848-858
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    • 2007
  • Sontag and Lee (2004) recently developed an objectively measurable instrument, the Proximity of Clothing to Self(PCS) Scale, which measured the psychological closeness of clothing to self. They validated a 4-factor, 24-item PCS Scale for use with adolescents and identified the need for confirmation of the factor structure with other age groups. This paper extends the work of Sontag and Lee by employing the PCS Scale with older persons, age 65 and over, and reports the validation of a 3-factor, 19-item PCS Scale for older persons. A mail survey was sent to a national random sample of 1,700 older Persons by means of a list purchased from a U.S. survey sampling company in late November 2004. Total usuable number of respondents was 250 with an adjusted response rate of 15.6 percent. Three analytical rounds of confirmatory factor analysis(CFA) to test the construct validity of the PCS Scale were conducted by using AMOS 5.0(Analysis of Moment Structures), one of several structural equation modeling(SEM) programs. Completion of three rounds of the CFA resulted in a 3-factor, 19-item PCS Scale with demonstrated construct validity and reliability for older persons. The three PCS dimensions are clothing in relation to 1) self as structure-process(PCS Dimension 1-2-3 combined), 2) self-esteem-evaluative and affective processes(PCS Dimension 4-5 combined), and 3) body image and body cathexis(PCS Dimension 6). The initially hypothesized 6-factor scale(Sontag & Lee, 2004) was not confirmed for adolescents in their study nor with older persons in this study. In addition, the 4-factor solution for the adolescent group did not hold for older persons. It appears that the self-system of older persons is more integrated than may be true for younger individuals. Recommendations for future testing of construct validity of the PCS Scale are made.

Status of Brain-based Artistic Education Fusion Study - Basic Study for Animation Drawing Education (뇌기반 예술교육 융합연구의 현황 - 애니메이션 드로잉 교육을 위한 기초연구)

  • Lee, Sun Ju;Park, Sung Won
    • Cartoon and Animation Studies
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    • s.36
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    • pp.237-257
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    • 2014
  • This study is the process of performing the interdisciplinary fusion study between multiple fields by identifying the status on the previous artistic education considering the brain scientific mechanism of image creativity and brain-based learning principles. In recent years, producing the educational methods of each field as the fusion study activities are emerging as the trend and thanks to such, the results of brain-based educational fusion studies are being presented for each field. It includes artistic fields such as music, art and dance. In other words, the perspective is that by understanding the operating principles of the brain while creativity and learning is taking place, when applying various principles that can develop the corresponding functions as a teaching method, it can effectively increase the artistic performance ability and creativity. Since the animation drawing should be able to intuitively recognize the elements of movement and produce the communication with the target beyond the delineative perspective of simply drawing the objects to look the same, it requires the development of systematic educational method including the methods of communication, elements of higher cognitive senses as well as the cognitive perspective of form implementation. Therefore, this study proposes a literature study results on the artistic education applied with brain-based principles in order to design the educational model considering the professional characteristics of animation drawing. Therefore, the overseas and domestic trends of the cases of brain-based artistic education were extracted and analyzed. In addition, the cases of artistic education studies applied with brain-based principles and study results from cases of drawing related education were analyzed. According to the analyzed results, the brain-based learning related to the drawing has shown a common effect of promoting the creativity and changes of positive emotion related to the observation, concentration and image expression through the training of the right brain. In addition, there was a case of overseas educational application through the brain wave training where the timing ability and artistic expression have shown an enhancement effect through the HRV training, SMR, Beta 1 and neuro feedback training that strengthens the alpha/seta wave and it was proposing that slow brain wave neuro feedback training contributes significantly in overcoming the stress and enhancing the creative artistic performance ability. The meaning of this study result is significant in the fact that it was the case that have shown the successful application of neuro feedback training in the environment of artistic live education beyond the range of laboratory but the use of the machine was shown to have limitations for being applied to the teaching methods so its significance can be found in providing the analytical foundation for applying and designing the brain-based learning principles for future animation drawing teaching methods.

The Analytical Study for Sika Deer's Behaviour Pattern and Characteristics of Their Habitats Through Monitoring the Sika Deer Released at the Urban Forests in South Korea (국내 도심지 숲에 방사된 꽃사슴 모니터링을 통한 행동양식 및 서식지 특성분석 연구)

  • Jin, Ki-Jung
    • Korean Journal of Environmental Biology
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    • v.31 no.4
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    • pp.322-332
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    • 2013
  • This study was conducted to understand the control mechanism of Sika deer (Cervus nippon taiouanus) populations which are adapted to the natural forest areas and the semi-natural forest areas of Korea. We monitored and analyzed the behaviour patterns and habitat characteristics of Sika deers. After we released 12 Sika deers (male 3, female 9) each at the two study areas in and around Seoul under the approval of Korean government, we monitored them through our survey researchers' naked eyes from May 2011 to January 2012. We discriminated their habitat patterns to 4 major places - eating food place, drinking water place, daytime rest place, and nighttime rest place. Our results showed that Sika deer preferred the open grassland habitats for feeding and resting in daytime but the closed bushland for their protection and sleep. We also found the recommended sex ratio of adult male to female in a herd was 1 : 4~9 for breeding and they had few cubs in a herd. The average amount of food for 1 adult deer was 391.62 kg of fresh grasses and 286.90 kg of hay per year. Our results suggest that the amount of drinking water required for a deer when grazed on grasses during spring and summer seasons is 256.8 L and when a deer feeds on dry food during autumn and winter seasons, 209.8 L of water is required. From these results, we observe that the amount of drinking water was affected substantially by the moisture content of their food. This observational study must be very valuable for land managers to judge the number of deers that should be released in natural areas without high risk and to ascertain the sex ratio of large mammals including Sika deer. Therefore, we conclude that this population control mechanism study consists of efficient basic data and their values must be very effective for various purposes.

Development of an Official Analytical Method for Determination of Imazapyr in Agricultural Commodities using HPLC-UVD (HPLC-UVD를 이용한 농산물 중 Imazapyr의 공정분석법 확립)

  • Jang, Jin;Kim, Heejung;Ko, Ah-Young;Lee, Eun-Hyang;Joo, Yoon Ji;Kim, Jinhong;Chang, Moon-Ik;Rhee, Gyu-Seek
    • The Korean Journal of Pesticide Science
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    • v.19 no.1
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    • pp.5-13
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    • 2015
  • A chromatographic method for the determination of imazapyr, a non-selective herbicide, in agricultural commodities was developed to use safety control of pesticide residue on crops, and was fully validated as an official method for residue analysis. Agricultural commodities, mandarin (fruit), hulled rice (cereal grains), pepper (vegetables), potato (potatoes) and soybean (beans) were extracted with methanol and partitioned with dichloromethane to remove the interference obtained from sample extracts, adjusting pH to 2.5 by 4N hydrochloric acid. Finally, they were analyzed by high performance liquid chromatography coupled to UV detector (HPLC-UVD). The developed method had the linearity in the range of test concentrations with coefficients of determination ($r^2$) more than 0.99. Recovery studies were carried out at three concentration levels (LOQ, 10LOQ, and 50LOQ) performing five replicates at each level. Recoveries were ranged between 72.1 to 108.0%, with relative standard deviations less than 10%. A consistent recovery was determined according to the CODEX guidelines (CAC/GL40, 2003). Finally, LC/MS with selected ion monitoring was also applied to confirm the suspected residues of imazapyr in agricultural samples. This developed method for determination of imazapyr residues in agricultural commodities. can be used as an official method.

Study on the calibration phantom and metal artifacts using virtual monochromatic images from dual energy CT (듀얼 에너지 CT의 가상 단색 영상을 이용한 영상 교정 팬텀과 금속 인공음영에 관한 연구)

  • Lee, Jun seong;Lee, Seung hoon;Park, Ju gyung;Lee, Sun young;Kim, Jin ki
    • The Journal of Korean Society for Radiation Therapy
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    • v.29 no.1
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    • pp.77-84
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    • 2017
  • Purpose: To evaluate the image quality improvement and dosimetric effects on virtual monochromatic images of a Dual Source-Dual Energy CT(DS-DECT) for radiotherapy planning. Materials and Methods: Dual energy(80/Sn 140 kVp) and single energy(120 kVp) scans were obtained with dual source CT scanner. Virtual monochromatic images were reconstructed at 40-140 keV for the catphan phantom study. The solid water-equivalent phantom for dosimetry performs an analytical calculation, which is implemented in TPS, of a 10 MV, $10{\times}10cm^2$ photon beam incident into the solid phantom with the existence of stainless steel. The dose profiles along the central axis at depths were discussed. The dosimetric consequences in computed treatment plans were evaluated based on polychromatic images at 120 kVp. Results: The magnitude of differences was large at lower monochromatic energy levels. The measurements at over 70 keV shows stable HU for polystyrene, acrylic. For CT to ED conversion curve, the shape of the curve at 120 kVp was close to that at 80 keV. 105 keV virtual monochromatic images were more successful than other energies at reducing streak artifacts, which some residual artifacts remained in the corrected image. The dose-calculation variations in radiotherapy treatment planning do not exceed ${\pm}0.7%$. Conclusion: Radiation doses with dual energy CT imaging can be lower than those with single energy CT imaging. The virtual monochromatic images were useful for the revision of CT number, which can be improved for target coverage and electron densities distribution.

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Studies on the Time Distribution of Heavy Storms (暴雨의 時間的 分布에 關한 硏究)

  • Lee, Keun-Hoo
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.26 no.2
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    • pp.69-84
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    • 1984
  • This study was carried out to investigate the time distribution of single storms and to establish the model of storm patterns in korea. Rainfall recording charts collected from 42 metheorological stations covering the Korean peninsula were analyzed. A single storm was defined as a rain period seperated from preceding and succeeding rainfall by 6 hours and more. Among the defined single storms, 1199 storms exceeding total rainfall of 80 mm were qualified for the study. Storm patterns were cklassified by quartile classification method and the relationship between cummulative percent of rainfalls and cummulative storm time was established for each quartile storm group. Time distribution models for each stations were prepared through the various analytical and inferential procedures. Obtained results are summarized as follows: 1. The percentile frequency of quartile storms for the first to the fourth quartile were 22.0%, 26.5%, 28.9% and 22.6%, respectively. The large variation of percentile frequency was show between the same quartile storms. The advanced type storm pattern was predominant in the west coastal type storm patterns predominantly when compared to the single storms with small total rainfalls. 3. The single storms with long storm durations tended to show delayed type storm patterns predominantly when compared to the single storms with short storm durations. 4. The percentile time distribution of quartile storms for 42 rin gaging stations was estimated. Large variations were observed between the percentiles of time distributions of different stations. 5. No significant differences were generally found between the time distribution of rainfalls with greater total rainfall and with less total rainfall. This fact suggests that the size of the total rainfall of single storms was not the main factor affecting the time distribution of heavy storms. 6. Also, no significant difference were found between the time distribution of rainfalls with long duration and with short duration. The fact indicates that the storm duration was no the main factor affecting the time distribution of heavy storms. 7. In Korea, among all single storms, 39.0% show 80 to 100mm of total rainfall which stands for the mode of the frequency distribution of total rainfalls. The median value of rainfalls for all single storms from the 42 stations was 108mm. The shape of the frequency distribution of total rainfalls showed right skewed features. No significant differences were shown in the shape of distribution histograms for total rainfall of quartile storms. The mode of rainfalls for the advanced type quartile storms was 80~100mm and their frequencies were 39~43% for respective quartiles. For the delayed type quartile storms, the mode was 80~100mm and their frequencies were 36!38%. 8. In Korea, 29% of all single storms show 720 to 1080 minutes of storm durations which was the highest frequency in the frequency distribution of storm durations. The median of the storm duration for all single storms form 42 stations was 1026 minutes. The shape of the frequency distribution was right skewed feature. For the advanced type storms, the higher frequency of occurrence was shown by the single storms with short durations, whereas for the delayed type quartile storms, the higher frequency was shown gy the long duration single storms. 9. The total rainfall of single storms was positively correlated to storm durations in all the stations throughout the nation. This fact was also true for most of the quartile storms. 10. The third order polynomial regression models were established for estimating the time distribution of quartile storms at different stations. The model test by relative error method resulted good agreements between estimated and observed values with the relative error of less than 0.10 in average.

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