• Title/Summary/Keyword: analytical methods

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Analysis of Volatile Organic Compounds in Sediments Using HS-GC/MS - Confirmation of Matrix Effects in External and Internal Standard Methods - (HS-GC/MS를 이용한 퇴적물 중 휘발성유기화합물 분석 - 외부 및 내부표준방법에서 매질영향 확인 -)

  • Shin, Myoung-Chul;Jung, Da-som;Noh, Hye-ran;Yu, Soon-ju;Seo, Yong-Chan;Lee, Bo-Mi
    • Journal of Korean Society on Water Environment
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    • v.37 no.6
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    • pp.510-519
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    • 2021
  • Volatile Organic Compounds (VOCs) in sediments, which can cause human health problems, have been monitored in Korea since 2014. Measured VOC concentrations can be affected by matrix type and the volatility of target substances. In this study, (1) VOCs volatility and the influence of matrix interference were confirmed, and (2) internal standards (IS) method was applied to improve analytical method. For these purposes, method detection limit (MDL), calibration linearity, precision and accuracy of VOCs were compared in various matrices using the IS. Some of VOCs in sediments showed different peak areas and reduced rates compared to water matrix. It was suggested that adsorption properties of sediments hindered the migration to vapor during heat pretreatment in headspace method. A calibration curve was created in clean sand. Recovery rates for the calibration curve method and IS applying method were 64.1~83.1% and 99.1~119.3%, respectively. Relative standard deviations ranged from 11.1% to 21.6% for the calibration curve method and those for IS ranged 4.7% to 13.7%. In case of real sediment, calibration curve and 1,2-Dichlorobenzene-d4 (ODCB) among IS were not suitable. The average recovery rate of Fluorobenzene (FBZ) increased by 56.4% and Relative Standard Deviation (RSD) by 4.7%. However, the recovery rate was increased in the samples with large values of igniting intensity. This study confirmed that influence of the matrix of VOCs in sediment, and addition of IS materials improved precision and accuracy. Although IS corrects volatilization and adsorption, it is recommended that more than two types of IS should be added rather than single.

A Study on Chinese Character Expressions of Dynamic Poster Design Based on Kinetic Typography Principle - Focused on '24 Solar Terms' Theme Poster - (키네틱 타이포그래피 원리에 기반을 둔 다이나믹 포스터 디자인의 한자 표현방식에 관한 연구 - '24절기' 테마 포스터를 중심으로 -)

  • Chu, Ziyi;Park, Yong-Jin
    • The Journal of the Korea Contents Association
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    • v.22 no.10
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    • pp.195-212
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    • 2022
  • Based on the kinetic typography principle and the structure features of Chinese characters, this study took the Chinese'24 solar terms' theme dynamic poster as the research object, explored the visual expression of dynamic Chinese characters, and tried to summarize the visual expression law of Chinese characters in dynamic poster design. It can be found that, there could be 6 different types of Chinese character expressions in the 24 solar terms poster design. Among them, 'Drawing' design method has the meaning of text structure and form expression, and 'Assembling' design method has the meaning of text stroke and texture association, also, 'Forming' design method bring its meaning through stroke deformation, 'Transforming' design method conveys the content through text disintegration, 'Replacing' design method mainly bring the meaning through simulation, while 'Rotation' design method always express through visual three-dimensional and space. Finally, the findings could not only provide analytical logic and methods for the expression of Chinese characters in dynamic poster design, but also fill the lack of formative research on dynamic Chinese characters, which hopefully provide basic information for the research related to dynamic Chinese character structure, as well as the dynamic poster designers.

Nutritional Analysis of Wild Conyza canadensis L. Extract (야생 망초(Conyza canadensis L) 추출물의 영양성분 분석)

  • Kim, Hong Yul;Song, Hyun Sook;Lee, Geo Lyong
    • Journal of Naturopathy
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    • v.11 no.2
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    • pp.100-108
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    • 2022
  • Background: It has been reported that various substances exist in wild Conyza canadensis, but I think that the overall compositional analysis is still insufficient. Purposes: This study was to set extraction conditions and search for various nutritional components in the wild C. canadensis. Methods: Various extracts were extracted and analyzed using different analytical instruments to suggest and study the conditions for component analysis. Results: As for the general nutritional components of C. canadensis leaf extract, carbohydrates were 46.4%, crude protein 26.5%, moisture 16.3%, raw meal 9.5%, and natural fat 1.2%. The dietary fiber content was 30.76%. Free fructose, glucose, sucrose, and maltose were separated, and the amount of fructose was as high as 4,144.2 mg/100 g. In addition, we found 64.87 mg/g of K, 4.09 mg/g of P, 1.77 mg/g of Mg, and 0.16 mg/g of disodium in the extracts. A total of 20 fatty acids have appeared. In addition, unsaturated fatty acids (octadecenoic acid, octadecadienoic acid, and linolenic acid) were detected. Linolenic acid was high at 54.1%. The saturated fatty acid content was 0.39 g/100 g, and the trans fatty acid content was 0.01 g/100 g. No cholesterol was found in the plant. Riboflavin was at 0.4 mg/100 g, with six essential amino acids and 24 amino acids. Conclusions: As a result of the primary research on the plant, various nutritional and functional ingredients exist in the extract, and natural healing uses are available.

Physiological Activities of wild Conyza canadensis L. Extracts (야생 망초(Conyza canadensis L) 에틸알코올 추출물의 생리활성)

  • Lee, Hee Jea;Song, Hyun Sook;Lee, Geo Lyong
    • Journal of Naturopathy
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    • v.11 no.2
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    • pp.109-115
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    • 2022
  • Background: Studies on the existence and activation of antioxidants in the wild Erigeron canadensis are still incomplete. Purposes: The activity of antioxidant substances was studied by extracting E. canadensis with ethyl alcohol. Methods: After washing the wild turfgrass, extraction with ethyl alcohol was used to investigate the activity of antioxidant substances using various analytical instruments. Results: The highest yield ratio of the extract was 49.3%, and it varied according to temperature and ethyl alcohol ratio. The 50:50 of water to ethyl alcohol at 180℃ was the highest yield. 100% survival rate was in the untreated group and 98-100% in the experimental group at 50 ppm or more of the extract. There was no cytotoxicity at almost all concentrations. The extract of 25 ppm was suppressed by 42% in the test group. The extract of 50 ppm reduced the free fatty acid content by 15%. Cell viability was 20% at the extract concentration of 50 ppm and 24% at 100 ppm. At an extract of 500 ppm, the free oxygen scavenging ability using DPPH and ABTs was 90-98%. When the changes in the free radical scavenging activity of DPPH and ABTs were observed in three dimensions, the antioxidant activity tended to increase at 85℃ as the temperature increased. However, at 85~130℃, it showed a rather decreasing tendency as the temperature increased. Conclusions: There were antioxidants in the ethyl alcohol extract of the wild grass, there was almost no cytotoxicity and suppressed NO production, and the scavenging function of free oxygen was also high. These results provide primary data for the various natural healing uses of the extracts of the turfgrass.

Assessment of a fresh submarine groundwater discharge in eastern Jeju Island using analytic seawater intrusion models (해수침투 해석해 기반 제주 동부 담해저 지하수 유출의 정량적 산정)

  • Kim, Il-Hwan;Chang, Sun Woo
    • Journal of Korea Water Resources Association
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    • v.55 no.12
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    • pp.1011-1020
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    • 2022
  • Previous studies for the assessment of submarine groundwater discharge (SGD) were perfomed for areas where a large amount of SGD was observed. Newly developed assessment methods were proposed that was based on an analytic solution using sharp interface model. The proposed mathematical equations used the existing observed groundwater level and hydrogeological data of Jeju Island as input data. The quantitatively assessed FSGD values were compared to the basin-scale recharge estimation values in Seong-San area in eastern Jeju. As a result of the study, it was estimated that the amount of FSGD in the Seongsan area ranges from about 2.65 to 9.15% of the amount of areal-recharge. Through the analysis of the FSGD combined with the analytic model, it is to be provided as a scientific tool to establish a more reasonable coastal water resource management plan.

Pediatric Inflammatory Bowel Disease: A Multicenter Study of Changing Trends in Argentina Over the Past 30 Years

  • Arcucci, Maria Soledad;Contreras, Monica Beatriz;Gallo, Julieta;Antoniska, Mariela Andrea;Busoni, Veronica;Tennina, Cecilia;D’Agostino, Daniel;Kakisu, Maria Hisae;Weyersberg, Christian;Orsi, Marina
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.25 no.3
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    • pp.218-227
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    • 2022
  • Purpose: To analyze the characteristics of pediatric inflammatory bowel disease (IBD) over the past three decades in Argentina and determine if there are differences between the first two decades and the past decade. Methods: We conducted a retrospective multicenter analytical study in children with IBD between 0 and 18 years of age diagnosed between 1987 and 2017 in three tertiary health centers in Argentina. The evaluation included clinical characterization, endoscopy, histology, and imaging data together with therapeutic strategies. The patients were divided into two groups: Group 1, diagnosed between 1987 and 2007, and Group 2, diagnosed between 2008 and 2017. Results: Of the 756 patients included, 409 (54%) had ulcerative colitis (UC), 250 (33%) had Crohn's disease (CD), and 97 (13%) had IBD-unclassified (IBD-U). The positive family history was 3.8%, which was more frequent among children under two years of age (6.7%). There were no significant differences in clinical presentation and extraintestinal manifestations between periods, with hepatic manifestations being the most frequent. In the last decade, we found an upward trend in CD, a downward trend in UC/IBD-U, even after adjustment for socioeconomic status, and a decrease of 50% in surgical treatments coinciding with the advent of biological therapy. Conclusion: This is the first multicenter cohort study in a Latin American country to describe clinical, endoscopic, and therapeutic data across the past 30-year period. Although CD was responsible for the overall increase in incidence, UC was still prevalent in this region.

Development of Standard Operating Procedures (SOPs), Standardization, TLC and HPTLC Fingerprinting of a Polyherbal Unani Formulation

  • Naaz, Arjumand;Viquar, Uzma;Naikodi, Mohammad Abdul Rasheed;Siddiqui, Javed Inam;Zakir, Mohammad;Kazmi, Munawwar Husain;Minhajuddin, Ahmed
    • CELLMED
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    • v.11 no.4
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    • pp.21.1-21.9
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    • 2021
  • Background: Unani System of Medicine (USM) has its origin to Greece. To ensure and develop the quality, authenticity of Unani drugs, standardization on modern analytical parameter is essential requirement for drugs. Objectives: The aimed of the present study was to develop a standard profile of "Qurṣ-e-Mafasil" by systematic study through authenticated ingredients, pharmacognostic identification followed by physicochemical, TLC, HPTLC fingerprinting analysis as per standard protocol. Material and Methods: In this study three batches of "Qurṣ-e-Mafasil" QM were prepared by standard method as per UPI had been followed by organoleptic properties of formulation such as appearance, color, odor, taste. Powder Microscopy and physicochemical studies were carried out such as Uniformity of weight, Friability, Disintegration time, hardness, LOD, ash vales and extractive values in like aqueous, alcohol & hexane. Further qualitative tests such as Thin-Layer Chromatography (TLC), and High-Performance Thin Layer Chromatography (HPTLC) studies were also carried out to develop fingerprint pattern of the alcoholic solvent extract of QM. Phytochemical screening was carried out in different solvent extracts such as alcoholic, aqueous and chloroform extracts to detect the presence phytoconstituents in the formulation QM. Heavy metals, Microbial Load Contamination and pesticidal residues were also determined. Results: Qurṣ-e-Mafasil showed tablet-like appearance, light brown colour, mild pungent odour and acrid taste. Uniformity of weight (mg), friability (rpm), and hardness (kg/cm) and disintegration time was ranged between (500 to 503), (0.0340 to 0.038), (8.40 to 8.67) and (4-5 minutes) respectively for the three batches. Loss in weight on drying at 105℃ was ranged between (8.3425 to 8.7346). Extracted values were calculated in distilled water ranged between (30.9091 to 31.4358), hexane (1.1419 to 1.4281), and alcohol (3.3352 to 3.3962). The ash values recorded were ranged between (3.7336 to 3.8378), and acid insoluble ash (0.5859 to 0.6112).

Non-Destructive Scientific Analysis of the Gold Fabric Excavated of Cheongsong Shim's Grave (청송심씨 묘에서 출토된 금직물의 비파괴 과학적 분석)

  • Lee, Hwang-Jo;Wi, Koang-Chul
    • Journal of Conservation Science
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    • v.38 no.3
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    • pp.243-253
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    • 2022
  • Using non-destructive analytical methods, we identified the material characteristics of two gold fabric artifacts excavated from the Cheongsong Sim clan (Bugeum Wonsam, Jikgeum Chima), including the artifact condition, fiber type, surface contamination, and metallic threads. We found that the artifacts were buried and had turned brown; thus, we were unable to determine their original color. The fiber type was determined to be silk from cocoons, based on scanning electron microscopy, Fourier transform infrared (FT-IR) analyses of Amide I, II, III, and IV peaks, and color reactions Further, the FT-IR and X-ray fluorescence (XRF) analyses identified the white and black stains as natural resin hydrolyzed substances, such as lipids and proteins, that occurred as microbial decomposition due to body decay. Finally, the XRF analyses identified the thin gold layer of the metallic yarn as gold (Au). According to the FT-IR data and the color reaction to the metallic yarn medium, the adhesive component of the medium was a product of-Amides I, II, III, and 3000 cm-1 within Amides A and B (an animal type), respectively. Thus, the medium was identified as Hanji (Korean paper), which is made from domestically produced Broussonetia kazinoki fibers.

An Analytical Study on Determination of Dimensions of Drystone Masonry Retaining Walls (석축의 단면결정에 대한 해석적 연구)

  • Seung-Hyun Lee
    • Journal of the Society of Disaster Information
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    • v.19 no.1
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    • pp.60-68
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    • 2023
  • Purpose: In order to find out stability condition which governs design of drystone masonry retaining walls and changing patterns of installed width of blocks of the wall for each stability conditions, typical wall was assumed and designed. Method: For the purpose of this study, 10 m high drystone masonry retaining wall with general block size and soil properties were considered and dimensions of the wall were determined by applying stability conditions of sliding and overturning and the design results were compared with each other. Result: According to the design results, installed width of blocks determined by considering stability of sliding were greatly less than those determined by considering stability of overturning and these differences were not decreased noticeably even though same values of factors of safety for sliding and overturning were applied. Between the two methods of determining the installed width of blocks, it could be seen that the method of considering failure wedge of lower part of overturning parts of the wall governed the design instead of considering horizontal base of overturning parts of the wall. Conclusion: In case of considering failure wedge of lower part of overturning parts of the wall, it could be seen that the installed width of blocks increased as the inclination angle of failure wedge increased. In case of considering overturning at the lower part of the wall with certain assumed inclination angle of failure wedge, it could be seen that installed width of blocks decreased as the inclination angle of failure wedge decreased by geometric restrictions of the wall.

Phthalate Exposure Levels and Related Factors in the Urban Low-Income Group: Focus on a Residential Disadvantaged Community (도시 저소득층의 프탈레이트 노출수준과 관련 요인: 거주 취약집단을 중심으로)

  • Dahee, Han;Jiyun, Kang;Seohui, Han;Su Hyeon, Kim;Hohyun, Jin;Chahun, Kim;Hosub, Im;Ki-Tae, Kim;Yong Min, Cho
    • Journal of Environmental Health Sciences
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    • v.48 no.6
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    • pp.315-323
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    • 2022
  • Background: Socioeconomical disadvantaged communities are more vulnerable to environmental chemical exposure and associated health effects. However, there is limited information on chemical exposure among vulnerable populations in Korea. Objectives: This study investigated chemical exposure among underprivileged populations. We measured urinary metabolites of phthalates in urban disadvantaged communities and investigated their correlations with residential environment factors and relative socioeconomic vulnerability. Methods: Urine samples were collected from 64 residents in a disadvantaged community in Seoul. A total of eight phthalate metabolites were analyzed by liquid chromatography-mass spectroscopy. Analytical method used by the Korean National Environmental Health Survey (KoNEHS) was employed. Covariate variance analysis and general linear regression adjusted with age, sex and smoking were performed. Results: Several phthalate metabolites, namely monomethyl phthalate (MMP), monoethyl phthalate (MEP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-n-butyl phthalate (MnBP) had higher levels than those reported in the adults of 4th KoNEHS. Notably, the MnBP level was higher in the lower socioeconomic group (geometric mean [GM]=47.3 ㎍/g creatinine) compared to non-recipients (GM=31.9 ㎍/g creatinine) and the national reference level (GM=22.0, 28.2 and 32.2 ㎍/g creatinine for adults, 60's and 70's, respectively.). When age, sex and smoking were adjusted, MEP and MnBP were significantly increased the lower socioeconomic group than non-recipients (p=0.014, p=0.023). The lower socioeconomic group's age of flooring were higher than non-recipients, not statistically significant. Conclusions: These results suggest that a relatively low income and aged flooring could be considered as risk factors for increased levels of phthalate metabolites in socioeconomic vulnerable populations.