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A Study on Standardization of Shinbaro Pharmacopuncture Using Herbal Medicines Identification Test and HPLC-DAD (신바로 약침의 한약재 확인시험 및 HPLC-DAD를 통한 표준화 연구)

  • Lee, Jin Ho;Kim, Min Jeong;Lee, Jae Woong;Kim, Me Riong;Lee, In Hee;Kim, Eun Jee
    • Journal of Acupuncture Research
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    • v.32 no.2
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    • pp.1-9
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    • 2015
  • Objectives : The present study was an evaluation and standardization of herbal components in order to establish the efficacy and safety of Shinbaro pharmacopuncture. Methods : Among the raw materials of Shinbaro pharmacopuncture, the components Cibotii Rhizoma, Eucommiae Cortex, and Ledebouriellae Radix were assessed through ingredient verification experiments using thin-layer chromatography(TLC) and ultraviolet rays(UV) lamps. In addition, we standardized Acanthopanacis Cortex and Achyranthis Radix through validation using high performance liquid chromatograph-diode array detector(HPLC-DAD). Results : As result appeared a blue-white fluorescence under ultraviolet rays; changed to dark green after adding 1 % ferric chloride solution(due to Cibotii Rhizoma), and presented a yellow-green fluorescence when mixed with an ethyl ether under UV lamps by way of the ethyl ether layer, confirming Eucommiae Cortex. Ledebouriellae Radix was confirmed as dark brown spots at Rf values of 0.56 and 0.71 using TLC. Additionally, Acanthopanacis Cortex and Achyranthis Radix HPLC test results showed that linearity was $R^2{\geq}0.99$, and detection limit and quantitation limit were 0.23 to $1.29{\mu}g/mL$, and 0.71 to $3.90{\mu}g/mL$, respectively. Furthermore, precision and accuracy were confirmed to have relative standard deviation(RSD) values of 0.10 to 1.89 % and 96.19 to 103.72 %, respectively. Shinbaro pharmacopuncture did not have any overlapping or interference from other peaks in detection under the abovementioned analysis conditions. Conclusions : In conclusion, we confirmed that maintenance of Shinbaro pharmacopuncture validity was possible by means of quality control of Cibotii Rhizoma, Eucommiae Cortex, and Ledebouriellae Radix through ingredient identification and Acanthopanacis Cortex and Achyranthis Radix through high performance liquid chromatograph(HPLC) analysis. Further, we hope to contribute to the development strategy of herbal industry acupuncture.

Gamma-ray Exposure Rate Monitoring by Energy Spectra of NaI(Tl) Scintillation detectors

  • Lee, Mo Sung
    • Journal of Radiation Protection and Research
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    • v.42 no.3
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    • pp.158-165
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    • 2017
  • Background: Nuclear facilities in South Korea have generally adopted pressurized ion chambers to measure ambient gamma ray exposure rates for monitoring the impact of radiation on the surrounding environment. The rates assessed with pressurized ion chambers do not distinguish between natural and man-made radiation, so a further step is needed to identify the cause of abnormal variation. In contrast, using NaI(Tl) scintillation detectors to detect gamma energy rates can allow an immediate assessment of the cause of variation through an analysis of the energy spectra. Against this backdrop, this study was conducted to propose a more effective way to monitor ambient gamma exposure rates. Materials and Methods: The following methods were used to analyze gamma energy spectra measured from January to November 2016 with NaI detectors installed at the Korea Atomic Energy Research Institute (KAERI) dormitory and Hanbat University. 1) Correlations of the variation of rates measured at the two locations were determined. 2) The dates, intervals, duration, and weather conditions were identified when rates increased by $5nSv{\cdot}h^{-1}$ or more. 3) Differences in the NaI spectra on normal days and days where rates spiked by $5nSv{\cdot}h^{-1}$ or more were studied. 4) An algorithm was derived for automatically calculating the net variation of the rates. Results and Discussion: The rates measured at KAERI and Hanbat University, located 12 kilometers apart, did not show a strong correlation (coefficient of determination = 0.577). Time gaps between spikes in the rates and rainfall were factors that affected the correlation. The weather conditions on days where rates went up by $5nSv{\cdot}h^{-1}$ or more featured rainfall, snowfall, or overcast, as well as an increase in peaks of the gamma rays emitted from the radon decay products of $^{214}Pb$ and $^{214}Bi$ in the spectrum. This study assumed that $^{214}Pb$ and $^{214}Bi$ exist at a radioactive equilibrium, since both have relatively short half-lives of under 30 minutes. Provided that this assumption is true and that the gamma peaks of the 352 keV and 1,764 keV gamma rays emitted from the radionuclides have proportional count rates, no man-made radiation should be present between the two energy levels. This study proved that this assumption was true by demonstrating a linear correlation between the count rates of these two gamma peaks. In conclusion, if the count rates of these two peaks detected in the gamma energy spectrum at a certain time maintain the ratio measured at a normal time, such variation can be confirmed to be caused by natural radiation. Conclusion: This study confirmed that both $^{214}Pb$ and $^{214}Bi$ have relatively short half-lives of under 30 minutes, thereby existing in a radioactive equilibrium in the atmosphere. If the gamma peaks of the 352 keV and 1,764 keV gamma rays emitted from these radionuclides have proportional count rates, no man-made radiation should exist between the two energy levels.

Three-dimensional assessment of condylar surface changes and remodeling after orthognathic surgery

  • Lee, Jung-Hye;Lee, Woo-Jin;Shin, Jae-Myung;Huh, Kyung-Hoe;Yi, Won-Jin;Heo, Min-Suk;Lee, Sam-Sun;Choi, Soon-Chul
    • Imaging Science in Dentistry
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    • v.46 no.1
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    • pp.25-31
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    • 2016
  • Purpose: This study was performed to evaluate condylar surface changes and remodeling after orthognathic surgery using three-dimensional computed tomography (3D CT) imaging, including comparisons between the right and left sides and between the sexes. Materials and Methods: Forty patients (20 males and 20 females) who underwent multi-detector CT examinations before and after surgery were selected. Three-dimensional images comprising thousands of points on the condylar surface were obtained before and after surgery. For the quantitative assessment of condylar surface changes, point-to-point (preoperative-to-postoperative) distances were calculated using 3D processing software. These point-to-point distances were converted to a color map. In order to evaluate the types of condylar remodeling, the condylar head was divided into six areas (anteromedial, anteromiddle, anterolateral, posteromedial, posteromiddle, and posterolateral areas) and each area was classified into three types of condylar remodeling (bone formation, no change, and bone resorption) based on the color map. Additionally, comparative analyses were performed between the right and left sides and according to sex. Results: The mean of the average point-to-point distances on condylar surface was $0.11{\pm}0.03mm$. Bone resorption occurred more frequently than other types of condylar remodeling, especially in the lateral areas. However, bone formation in the anteromedial area was particularly prominent. No significant difference was found between the right and left condyles, but condylar surface changes in males were significantly larger than in females. Conclusion: This study revealed that condylar remodeling exhibited a tendency towards bone resorption, especially in the lateral areas. Condylar surface changes occurred, but were small.

Standard Measurement Procedure for Soil Radon Exhalation Rate and Its Uncertainty

  • Seo, Jihye;Nirwono, Muttaqin Margo;Park, Seong Jin;Lee, Sang Hoon
    • Journal of Radiation Protection and Research
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    • v.43 no.1
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    • pp.29-38
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    • 2018
  • Background: Radon contributing about 42% of annual average dose, mainly comes from soil. In this paper, standard measurement procedures for soil radon exhalation rate are suggested and their measurement uncertainties are analyzed. Materials and Methods: We used accumulation method for estimating surface exhalation rate. The closed-loop measurement system was made up with a RAD7 detector and a surface chamber. Radon activity concentrations in the system were observed as a function of time, with data collection of 5 and 15-minute and the measurement time of 4 hours. Linear and exponential fittings were used to obtain radon exhalation rates from observed data. Standard deviations of measurement uncertainties for two approaches were estimated using usual propagation rules. Results and Discussion: The exhalation rates (E) from linear approach, with 30 minutes measurement time were $44.8-48.6mBq{\cdot}m^{-2} {\cdot}s^{-1}$ or $2.14-2.32atom{\cdot}cm^{-2}{\cdot}s^{-1}$ with relative measurement uncertainty of about 10%. The contributions of fitting parameter A, volume (V) and surface (S) to the estimated measurement uncertainty of E were 59.8%, 30.1% and 10.1%, in average respectively. In exponential fitting, at 3-hour measurement we had E ranged of $51.6-69.2mBq{\cdot}m^{-2} {\cdot}s^{-1}$ or $2.46-3.30atom{\cdot}cm^{-2}{\cdot}s^{-1}$ with about 15% relative uncertainty. Fitting with 4-hour measurement resulted E about $51.3-68.2mBq{\cdot}m^{-2} {\cdot}s^{-1}$ or $2.45-3.25atom{\cdot}cm^{-2}{\cdot}s^{-1}$ with 10% relative uncertainty. The uncertainty contributions in exponential approach were 75.1%, 13.4%, 8.7%, and 2.9% for total decay constant k, fitting parameter B, V, and S, respectively. Conclusion: In obtaining exhalation rates, the linear approach is easy to apply, but by saturation feature of radon concentrations, the slope tends to decrease away from the expected slope for extended measurement time. For linear approach, measurement time of 1-hour or less was suggested. For exponential approach, the obtained exhalation rates showed similar values for any measurement time, but measurement time of 3-hour or more was suggested for about 10% relative uncertainty.

Evaluation of the Level of Microbial Contamination in the Manufacturing and Processing Company of Red Pepper Powder (고춧가루 제조.가공업체의 시설 및 공정별 미생물학적 오염도 평가)

  • Woo, Hye-Im;Kim, Jong-Bae;Choi, Ji-Hee;Kim, Eun-Hye;Kim, Dong-Sul;Park, Kun-Sang;Kim, Eun-Jeong;Eun, Jong-Bang;Om, Ae-Son
    • Journal of Food Hygiene and Safety
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    • v.27 no.4
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    • pp.427-431
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    • 2012
  • This study was conducted to monitor and evaluate microbial contamination during manufacturing process in 6 red pepper powder factories. Red pepper powder samples were taken from manufacturing facilitates, working area and workers' hands to determine sanitary indicator bacteria (SIB) such as aerobic bacteria and coliform group as well as pathogenic indicator bacteria (PIB) such as Staphylococcus aureus, E.coli, Salmonella spp., Listeria monocytogenes, and Bacillus cereus. The results indicated that SIB in primary materials was detected as low as 3 log units and E.coil and Staphylococcus aureus of PIB were detected. After grinding process, aerobic bacteria, fungi, and coliform group increased 52% and 108%, respectively. In final products, PIB was not detected except for one found Staphylococcus aureus by which workers' hands were contaminated. Moreover, UV detectors in all the manufacturers were not able to reduce bacteria. Thus, this data suggest that a stringent safety management be needed to prevent cross contamination, and also reconsider effectiveness of facility.

Determination of Vitamin B6 Content using HPLC in Agricultural Products cultivated in Local Areas in Korea (HPLC를 이용한 지역 농산물의 비타민 B6 함량 분석)

  • Choi, So-Ra;Song, Eun-Ju;Song, Young-Eun;Choi, Min-Kyung;Han, Hyun-Ah;Lee, In-Sok;Shin, So-Hee;Lee, Ki-Kwon;Choi, Young-Min;Kim, Haeng-Ran
    • The Korean Journal of Food And Nutrition
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    • v.30 no.4
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    • pp.710-718
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    • 2017
  • Contents of water soluble vitamin $B_6$ in a total of 62 agricultural products cultivated in local areas in Korea were analyzed by high performance liquid chromatography with fluorescence detector (HPLC/FLD). To verify the method of vitamin $B_6$ analysis, a quality control chart was formulated with in-house control using a mixture of broccoli and shiitake mushrooms. Among cereals, high content of vitamin $B_6$ measured $234.3{\sim}260.3{\mu}g/100g$ in dried mung bean and soybean. Vitamin $B_6$ content of non-glutinous and glutinous black rice measured $105.0{\mu}g/100g$ and $129.7{\mu}g/100g$, respectively. In vegetables, high content of vitamin $B_6$ were measured in passion fruit ($104.3{\mu}g/100g$), gat ($55.7{\sim}84.3{\mu}g/100g$), gomchwi ($31.3{\sim}88.0{\mu}g/100g$) and garlic ($72.7{\sim}98.3{\mu}g/100g$). Among fruits, gold kiwi 'Zespri' and green kiwi 'Hayward' revealed high vitamin $B_6$ content of $116.3{\mu}g/100g$ and $78.7{\mu}g/100g$, respectively. In persimmons, daebongsi had high vitamin $B_6$ content ($36.0{\sim}72.7{\mu}g/100g$) than bansi and sweet persimmon. Vitamin $B_6$ content in dried jujube and persimmon increased more than $86.7{\mu}g/100g$ compared to fresh materials. Among specialty crops, green tea powder ($64.7{\sim}251.0{\mu}g/100g$) and sansuyu ($172.3{\mu}g/100g$) revealed high content. Of mushrooms, vitamin $B_6$ content of Sparassis crispa ($139.3{\mu}g/100g$) was the highest. Vitamin $B_6$ content information of agricultural products in local areas in Korea collected from this experiment will be used as valuable preliminary data for grasp national nutritional status.

A Study on the Emission of VOCs in Parking Lot Floor Coating (주차장 바닥 코팅제의 휘발성유기화합물 배출에 관한 연구)

  • Lee, Seung-Chan;Yoon, Gil-Ho;Park, Yong-Soon;Kil, Bae-Su;Yoon, Hyun-Do
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.23 no.4
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    • pp.152-158
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    • 2019
  • Measure the type and content of VOCs for A-company epoxy coating and B-company floor coating(Type A, B), which are used as flooring materials for parking lots. Than the VOCs used gas detectors to measure gas emissions, assuming the worst environment to reduce errors in external environments in the formaldehyde, toluene and xylene harmful to workers and tenants. As a result, A-company epoxy coating has the largest amount of VOCs, and compared to A-company epoxy coating, B-company floor coating of A type represented about 79% less and B type about 96% less. In addition, A-company epoxy coating was also the highest in gas emission measurement for formaldehyde, toluene and xylene using gas detector after 1 hour and 8 hours in closed environment conditions. B-company floor coating A type was less than A-company epoxy coating, which was about 42.3% less measured. And type B satisfied all TWA even in closed environment conditions.

Study of Condition Analysis and Diagnosis on Oil Paintings with Terahertz Imaging (테라헤르츠 이미징기법을 이용한 유화의 상태분석 및 진단)

  • Baek, Na Yeon;Song, You Na;Kim, Moon Jeong;Chung, Yong Jae;Lee, Han Hyoung
    • Journal of Conservation Science
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    • v.35 no.3
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    • pp.237-244
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    • 2019
  • In this study, we applied terahertz imaging technology to three Korean modern oil paintings ('Boy,' 'Girl,' and 'Hyehwadong Landscape'); investigated the types of inner layer information in the pictures that can be extracted with terahertz imaging technology; and analyzed the conditions for extracting them. The biggest problem in the terahertz imaging analysis we encountered was the image distortion caused by the change of the distance between the target surface and the terahertz detector, depending on the surface curvature of the target paintings. We then developed a 'working distance maintaining device' to solve this problem. As a result, the terahertz imaging technique was used to identify the base material characteristics and any patterns of damage inside, and presented the optimal conditions for identifying each characteristic. In addition, it was useful to employ the terahertz frequency-division image to check the characteristics of the background materials. To confirm coloring techniques such as brush strokes, it is effective to compare the maximum reflection peak image with the cross-section image; and to detect damage information inside the paintings that cannot be observed on the surface, to compare the cross-section image with the frequency-division image. On the other hand, according to the terahertz imaging analysis of the oil paintings, the internal structural damage marks of 'Boy' and 'Girl' were confirmed, and the artist's painting style was confirmed in 'Hyehwadong Landscape.' The above results are expected to be useful for the analysis and diagnosis of Korean modern oil paintings for their preservation.

Simultaneous determination of 9 preservatives in processed foods using high-performance liquid chromatography with photo diode array detector (HPLC-PDA를 이용한 가공식품 중 보존료 9종 동시분석)

  • Lee, Do-Yeon;Kim, Min-Hee;Ahn, Jang-Hyuk
    • Analytical Science and Technology
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    • v.33 no.6
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    • pp.233-239
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    • 2020
  • This study was performed to develop an analytical method using Carrez reagents as the precipitant to effectively and easily remove proteins and lipids while pretreating samples for the simultaneous determination of preservatives, including dehydroacetic acid (DHA), sorbic acid (SA), benzoic acid (BA), methyl ρ-hydroxybenzoate (MP), ethyl ρ-hydroxybenzoate (EP), propyl ρ-hydroxybenzoate (PP), isopropyl ρ-hydroxybenzoate (IPP), butyl ρ-hydroxybenzoate (BP), and isobutyl ρ-hydroxybenzoate (IBP). The effective selectivity was determined by HPLC separation analysis for nine preservatives in the test solution, after removing interfering materials such as lipids and proteins. The method developed in this study showed excellent linearity at 0.999 or higher. The limit of detection (LOD) ranged from 0.09 to ~0.12 mg/L and the limit of quantitation (LOQ) was ~0.280.37 mg/L. The results of the recovery test on processed foods, including pickles, cheeses, processed meat products, beverages, sauces, and emulsified foods showed DHA, SA, BA, MP, EP, IPP, PP, IBP, and BP at 90.9~107.7 %, 85.4~113.7 %, 90.7~111.6 %, 84.5~111.2 %, 81.3~110.9 %, 82.5~102.2 %, 81.1~110.0 %, 80.9~109.0 %, and 82.4~110.3 %, respectively. The probability of the simultaneous analytical method developed in this study as a quantitative method was confirmed for various processed foods.

Study of Naturally Occurring Radioactive Material Present in Deep Soil of the Malwa Region of Punjab State of India Using Low Level Background Gamma-Ray Spectrometry

  • Srivastava, Alok;Chahar, Vikash;Chauhan, Neeraj;Krupp, Dominik;Scherer, Ulrich W.
    • Journal of Radiation Protection and Research
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    • v.47 no.1
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    • pp.16-21
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    • 2022
  • Background: Epidemiological observations such as mental retardation, physical deformities, etc., in children besides different types of cancer in the adult population of the Malwa region have been reported. The present study is designed to get insight into the role of naturally occurring radioactive material (NORM) in causing detrimental health effects observed in the general population of this region. Materials and Methods: Deep soil samples were collected from different locations in the Malwa region. Their activity concentrations were determined using low-level background gammaray spectrometry. High efficiency and high purity germanium detector capped in a lead-shielded chamber having a resolution of 1.8 keV at 1,173 keV and 2.0 keV at the 1,332 keV line of 60Co was used in the present work. Data were evaluated with Genie-2000 software. Results and Discussion: Mean activity concentrations of 238U, 232Th, and 40K in deep soil were found to be 101.3 Bq/kg, 65.8 Bq/kg, and 688.6 Bq/kg, respectively. The mean activity concentration of 238U was found to be three and half times higher than the global average prescribed by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). It was further observed that the activity concentration of 232Th and 40K has a magnitude that is nearly one and half times higher than the global average prescribed by UNSCEAR. In addition, the radioisotope 137Cs which is likely to have its origin in radiation fallout was also observed. It is postulated that the NORM present in high quantity in deep soil somehow get mobilized into the water aquifers used by the general population and thereby causing harmful health problems. Conclusion: It can be stated that the present work has been able to demonstrate the use of low background gamma-ray spectrometry to understand the role of NORM in causing health-related effects in a general population of the Malwa region of Punjab, India.