• Title/Summary/Keyword: Mass standards

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A Study on the Effective Educational and Promotional Strategies for the Special Act on the Safety Management of Children's Dietary Life (어린이 식생활 안전관리 특별법에 관한 효과적 교육 및 홍보 방안 연구)

  • Hong, Jin-Im;Jeong, Hee-Sun
    • Culinary science and hospitality research
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    • v.18 no.5
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    • pp.176-189
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    • 2012
  • This study was conducted to investigate the effective educational and promotional strategies for the Special Act on the Safety Management of Children's Dietary Life on the basis of the survey conducted on parents. First of all, its result showed that most parents are well aware of the main contents of the law. They answered that, when choosing safe favorite food for children, the most important part is the article "Regulations on the standards for children's favorite food should be reinforced." As for the index of safety management for children's dietary life, most respondents think safety the most important; housewives and nuclear family members choose safety (p<.01), while large family members do nutrition. For the question asking how they get the information on safety management for children's dietary life, most of them answered that they generally use mass media, family and friends as a reference. Those with high income usually get the information from special books, those between 30s and 50 from mass media, and those with college graduates from civil social groups (p<.05). In case of taking the safety education programs for children's dietary life, they told that the most necessary information is concerned with hygienic dietary life and nutrition labeling on processed food; housewives are interested in the latter, while working people in the former (p<.05). As a method of informing parents of the Special Act on the Safety Management of Children's Dietary Life, mass media such as TV and radio, and school education are suggested in this survey. Therefore, this study proposes that mass media be considered as the most effective way of promoting the Special Act on the Safety Management of Children's Dietary Life and getting information concerning the law.

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An analysis of benzoic acid, methyl paraben and butyl paraben in soy sauce using isotope dilution liquid chromatography mass spectrometry (동위원소희석 질량분석법을 이용한 간장 중의 안식향산, 메틸파라벤, 부틸파라벤의 분석)

  • Ahn, Seonghee
    • Analytical Science and Technology
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    • v.31 no.6
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    • pp.225-231
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    • 2018
  • Benzoic acid, methyl paraben, and butyl paraben are preservatives that have been used in pharmaceutical, cosmetic, and food products. However, as their toxicities for human have been reported, many nations and organizations including Korea have established a regulation limit for thier usage of these preservatives in food products. The present study developed the isotope dilution liquid chromatography mass spectrometry method for accurate determination of three target preseratives in soysauce. In this study, the isotope dilution liquid chromatography mass spectrometry method was developed for accurate determination of three target preservatives in soy sauce. LC separation was optimized considering the pKa of benzoic acid which is lower than those of methyl and butyl parabens. A C18 column was used with 5 mM ammonium acetate and methanol as mobile phases. Mass spectrometry was operated in negative mode and selected reaction monitoring mode (SRM). Soy sauce sample was cleaned-up with C18 SPE cartridge for removing matrix inferences and color material. Optimized conditions and the method were validated with soy sauce reference materials for the analysis of food preservatives from Health Science Authority in Singapore. The measured values of benzoic acid, methyl and butyl paraben agreed well with reference values within their uncertainties.

Non-clinical Trials using 14C-Acetaminophen to Validate Biomedical Accelerator Mass Spectrometry System (14C-아세트아미노펜 비임상시험을 통한 생체시료 분석용 가속질량분석기의 검증)

  • Jinho Song;Jae Hoon Shim;Jung Bae Park;Chang Su Yeo;Soo Hyeon Bae;Min Sun Choi;Mi Hye Kwon;Kyeong Min Kim
    • Journal of Radiation Industry
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    • v.17 no.2
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    • pp.127-134
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    • 2023
  • Pharmacokinetic (PK) data provide pivotal information in drug development, and they are usually first studied in the preclinical stage using various animals. However, quite often, animal PK data may not match with human PK, especially in metabolites. Thus, most regulatory agencies in the world make it mandatory to obtain metabolite information using 14C radiolabeled drug in human for small molecule drug candidates. However, such studies are expensive and time consuming and they are usually done at the end of Phase II trials using ~3.7 MBq of 14C labeled drug in a limited number of human subjects. Introduction of accelerator mass spectrometry (AMS) in this kind of study has revolutionized it. Since AMS can measure 14C level as close as natural abundance, it can quantify the amounts of 14C labeled drugs and their metabolites produced in human body that consumes less than the amount of 0.0037 MBq of 14C labeled drug, a very safe level of radioactive dose in human. Therefore, it is now possible to conduct human 14C studies safely in early clinical trials without spending hefty amount of money and time. Korea Radioisotope Center for Pharmaceuticals(KRICP) at Korea Institute of Biological and Medical Sciences(KIRAMS) has established an AMS facility in 2018, housing a 0.5MV AMS manufactured at the US National Electrostatics Corps (NEC). The AMS instrument has been validated using various standard samples that have been prepared at Lawrence Livermore National Laboratory in the US, a worldly reputable provider of AMS standards. In this paper, we present a mass balance study for acetaminophen in rats using AMS and prove that the study results are equivalent with those of literature, which shows the AMS facilities at KRICP has successfully installed and be ready to be used in the various PK studies using 14C labelled compounds for new drug development.

Inspection on the Influence of Asian Dust on the Distribution of Atmospheric Mercury Observed for a Long Time (장기간 관측을 통한 황사 현상이 수은의 분포에 미치는 영향 고찰)

  • Lee, Jeong-Soon;Kim, Min-Young;Kim, Ki-Hyun;Hong, S.M.;Son, Z.H.;Lee, S.C.
    • Journal of Korean Society for Atmospheric Environment
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    • v.23 no.2
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    • pp.169-182
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    • 2007
  • To evaluate the possibly potent role of Asian Dust (AD) on the long range transport of Hg, statistical analyses were carried out using the hourly concentration data of gaseous elemental mercury (Hg) along with relevant environmental parameters. For the purpose of this study, Hg data were collected from Yang-Jae monitoring station in Seoul, Korea during Sept. 1997 to June 2002. During the study period, Hg concentrations in non-AD period ranged from $0.03\;to\;32.70\;ng\;m^{-3}$ with a mean $5.27{\pm}3.06\;ng\;m^{-3}$, while those in AD period from $1.79\;to\;32.60\;ng\;m^{-3}$ with a mean $5.20{\pm}3.06\;ng\;m^{-3}$. The air quality during AD were typically deteriorated by enhanced PM10 mass concentration (by $2{\sim}5$ times) compared to non-AD period, however comparison of the Hg concentration data indicates that they are not critically distinguished between events of AD and non-AD, except for the high minimum level of Hg during AD. The results of correlation and factor analysis also indicated somewhat complex patterns; in the case of AD events, Hg and $SO_{2}$ were assorted concurrently into a same factor. Evidence collected from this study thus suggests that long-range transport of Hg, if occurring, is unlikely to raise statistically Hg concentration levels such as seen during AD event. However, in nighttime of winter season, Hg concentrations are higher during AD (along with PM10 levels) than non-AD period. Although such observations suggest the effect of long range transport on the enhancement of Hg concentrations, more deliberate analysis may be required to track down the effect of such mechanism in relation with various factors including the air mass transport route.

Quantification of urea in serum by isotope dilution HPLC/MS (동위원소 희석 HPLC/MS에 의한 혈청 내 urea의 정량)

  • Lee, Hwashim;Park, Sangryoul
    • Analytical Science and Technology
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    • v.18 no.4
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    • pp.271-277
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    • 2005
  • Urea in blood has been measured as an effective marker for diagnosis of renal function. Urea which is e end-product of nitrogen containing metabolites such as proteins is filtered through glomeruli of kidneys and then excreted as urine. If the renal function is deteriorated, the urea concentration in blood will be increased, from which the healthiness of renal function is judged. In order to improve the confidence of diagnosis results, the results must keep traceability chain to certified reference materials, which was certified by primary reference method. In this study, we proposed isotope dilution-liquid chromatography/mass spectrometry (ID-LC/MS) as a candidate primary method, in which $15^N_2$-urea is used as an internal reference material. The developed method is highly accurate in principle and is convenient as it does not require cumbersome derivatization. 0.1 mmol/L ammonium chloride was selected as a mobile phase for HPLC because it provided low interference in MS analysis of relatively low molecular weighted urea. HPLC and MS were connected with an electrospray ionization (ESI) interface of positive mode, which provided high sensitivity and reproducibility. The developed method was validated with internationally recognized reference materials, and we have obtained satisfactory results in an international ring trial. The expanded uncertainty calculated according to ISO guide was 1.8% at 95% confidence interval. The developed method is being used as a primary reference measurement method such as for certification of serum certified reference materials (CRMs).

Analysis on Green BIM based Atrium Sizes in the Early Design Stage (Green BIM기반 초기설계 단계에서 타입별 아트리움의 규모산정에 관한 연구)

  • Jeong, Seung-Woo;Lee, Kweon-Hyoung;Kim, In-Han;Choo, Seung-Yeon
    • Korean Journal of Computational Design and Engineering
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    • v.18 no.1
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    • pp.58-70
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    • 2013
  • This study for establishing specific standards of atrium design aims to discuss design of atrium to consider energy performance atrium in office buildings. In order to evaluate a type and a scale of atrium at the early design stage, modeling details of mass design were set as standards of conceptual design. In the experiment, Project Vasari was used to analyze modeling and energy consumption, based on the LOD 100-step suggested by AIA, because there is no guideline to specify a level of modeling details at each design process. From this analysis, the correlation among a simple-typed atrium and scale and energy load was considered. The result of this research is as follows: First, the single-sided atrium reduced energy the most, and it was followed by three-sided, two-sided, four-sided and continuous-typed ones. On the whole, they could decrease energy by up to about 15%. Also, the atrium with a wide facade facing in the south was more favorable to reduce energy. Second, planning the atrium within 10~30% of the whole building area was more energy efficient. Third, rather than the depth, adjusting the length in designing an atrium could reduce cooling and heating loads by 1.5% per 1m. As explained above, energy performance evaluation considering types and planning elements of atrium helps to assess alternatives in a reasonable way. In particular, considering the use of building needs to be preceded to select a type of atrium, although it is also important to consider its planning elements.

Arabidopsis thaliana as Bioindicator of Fungal VOCs in Indoor Air

  • Lee, Samantha;Hung, Richard;Yin, Guohua;Klich, Maren A.;Grimm, Casey;Bennett, Joan W.
    • Mycobiology
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    • v.44 no.3
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    • pp.162-170
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    • 2016
  • In this paper, we demonstrate the ability of Arabidopsis thaliana to detect different mixtures of volatile organic compounds (VOCs) emitted by the common indoor fungus, Aspergillus versicolor, and demonstrate the potential usage of the plant as a bioindicator to monitor fungal VOCs in indoor air. We evaluated the volatile production of Aspergillus versicolor strains SRRC 108 (NRRL 3449) and SRRC 2559 (ATCC 32662) grown on nutrient rich fungal medium, and grown under conditions to mimic the substrate encountered in the built environment where fungi would typically grow indoors (moist wallboard and ceiling tiles). Using headspace solid phase microextraction/gas chromatography-mass spectrometry, we analyzed VOC profiles of the two strains. The most abundant compound produced by both strains on all three media was 1-octen-3-ol. Strain SRRC 2559 made several terpenes not detected from strain SRRC 108. Using a split-plate bioassay, we grew Arabidopsis thaliana in a shared atmosphere with VOCs from the two strains of Aspergillus versicolor grown on yeast extract sucrose medium. The VOCs emitted by SRRC 2559 had an adverse impact on seed germination and plant growth. Chemical standards of individual VOCs from the Aspergillus versicolor mixture (2-methyl-1-butanol, 3-methyl-1-butanol, 1-octen-3-ol, limonene, and ${\beta}-farnesene$), and ${\beta}-caryophyllene$ were tested one by one in seed germination and vegetative plant growth assays. The most inhibitory compound to both seed germination and plant growth was 1-octen-3-ol. Our data suggest that Arabidopsis is a useful model for monitoring indoor air quality as it is sensitive to naturally emitted fungal volatile mixtures as well as to chemical standards of individual compounds, and it exhibits relatively quick concentration- and duration-dependent responses.

Metal concentrations of Chinese herbal medicine products in the United States

  • Lee, Sun-Dong;Shin, Heon-Tae;Park, Hae-Mo;Ko, Seong-Gyu;Kook, Yoon-Bum;Ryu, Jin-Yeol;Kim, Hyun-Do;Hu, Howard;Park, Sung-Kyun
    • Advances in Traditional Medicine
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    • v.10 no.4
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    • pp.294-303
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    • 2010
  • We determined arsenic, lead, mercury and cadmium concentrations in Chinese herbal medicines sold in the United States by medical use parts. 54 kinds of herbal products including 9 medical use parts (radix, rhizoma, cortex, pericarpium, fructus, lignum, semen, folium, and herba) were analyzed using inductively coupled plasma-mass spectrometry for arsenic, lead and cadmium, and using mercury analyzer for mercury. Arsenic (median concentration, 0.25 mg/g), mercury (0.20 mg/g), lead (3.78 mg/g) and cadmium (0.39 mg/g) were detected in 71%, 54%, 35%, and 18% of 143 herbal medicine samples, respectively. A total of 27% and 12% of 143 products analyzed contained mercury and cadmium above the regulatory standards. Herba and folium (leaves of herbal plants) were the most contaminated parts from metals, whereas pericarpium, lignum and semen (outer layers and seeds) were less contaminated. This study suggests that metal contamination is different by medical use parts. Our findings provide further evidence that efforts to protect people using traditional remedies from metal intoxication should be made to enforce the regulatory standards.

Development of Contact-Type Thickness Measurement Machine using LVDT Sensors (LVDT센서를 이용한 접촉식 두께자동측정기 개발)

  • Shin, Ki-Yeol;Hwang, Seon
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.14 no.4
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    • pp.151-159
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    • 2015
  • In this study, we developed an automated contact-type thickness measurement machine that continuously and precisely measures the thickness of a PCB module product using multi-LVDT sensors. The system contains a measurement part to automatically measure the thickness in real time according to the set conditions with an alignment supply unit and unloading unit to separate OK and NG products. The sensors were calibrated before assembly in the measuring machine, and precision and accuracy performance tests were also performed to reduce uncertainty errors in the measurement machine. In the calibration test, the precision errors of the LVDT sensor were determined to be $1-3{\mu}m$ as 0.1% at the measuring range. A measurement error of 0.8 mm and 1.0 mm thickness test standards were found to be $1{\mu}m$ and $4{\mu}m$, and the standard deviations of two 1.0 mm products were measured as $14{\mu}m$ and $8{\mu}m$, respectively. In the measurement system analysis, the accuracies of test PCB standards were found to be $2{\mu}m$ and $3{\mu}m$, respectively. From the results of gage repeatability and reproducibility (R & R) crossed, we found that the machine is suitable for the measurement and process control in the mass production line as 7.92% of total gage R & R and in seven distinct categories. The maximum operating speed was limited at 13 pcs/min, showing a value good enough to measure.

Some Effects of Acid Concentrations in Inductively Coupled Plasma Atomic Emission Spectrometry and Inductively Coupled Plasma Mass Spectrometry (유도결합 플라즈마 원자방출분광법 및 질량분석법에서 산의 농도에 의한 영향)

  • Cho, Man-Sik;Lim, Heoungbin;Kim, Young-Sang;Lee, Kwang-Woo
    • Analytical Science and Technology
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    • v.5 no.3
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    • pp.277-283
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    • 1992
  • Acid effects on the ICP-AES signals are studied as the concentrations of nitric acid, hydrochloric acid, sulfuric acid, and 1:1 mixture of nitric acid and hydrochloric acid are changed. Almost all analyte signals are depressed. The extent of the depression due to the pressence of the acids became to be pecular when the acid concentration was over 1%. Among the acids used, the suppression due to sulfuric acid is most severe and unexpectable. The ratios of the analyte signal to Ar signal and the Mg II signal to Mg I signal are measured as the concentration of the acids changed. In this study, it is proved that the main reason of the signal reduction is the change in the nebulization efficiency, for example, droplet size distribution, viscosity and surface tension variation, not the alteration of plasma excitation characteristics. There was no relationship found between ionization potential and analyte signal reduction in ICP-MS.

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