• The Korean Journal of Pesticide Science
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• v.16 no.1
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• pp.35-42
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• 2012

This study was carried out to elucidate the residual characteristics and calculate processing factors of difenoconazole in ginseng and its processed products, such as dried ginseng, red ginseng and their water and alcohol extracts. The pesticide was sprayed onto the ginseng according to its pre-harvest intervals in 2009 (four-year-old ginseng) and 2010 (five-year-old ginseng). Harvested ginseng was processed to dried ginseng, red ginseng and their extracts according to the commercially well-qualified conventional methods provided by the Korea Ginseng Corporation. Limit of detection (LOD) and limit of quantitation (LOQ) of difenoconazole in fresh ginseng were 0.001 and 0.003 mg/kg, respectively. In case of processed ginseng products, their levels were 0.002 and 0.007 mg/kg, respectively. Concentration of difenoconazole in both fresh ginseng and its processed products increased with the experimental period. Processing factors, calculated as a ratio of difenoconazole concentration in processed products to fresh ginseng were found to be 1.71 to 2.17 and 1.62 to 2.03 in case of dried and red ginseng, respectively, while those for their extracts ranged from 1.76 to 2.98. In case of five-year-old dried ginseng and red ginseng as well as their extracts, the ranges of processing factor of difenoconazole were found to be 2.9 to 3.1, 1.9 to 2.2 and 2.4 to 4.7, respectively.

• Korean Journal of Food Science and Technology
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• v.42 no.3
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• pp.287-291
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• 2010

In this study, a simple and rapid pre-treatment method based on liquid extraction was applied for the simultaneous determination of three macrolides (spiramycin, tylosin, and tilmicosin) residues. In these studies, the stock farm products was used as a matrix sample. When the liquid extraction method was compared with the solid phase extraction (SPE) method, the former showed higher recovery percentages and simpler steps than the latter. The macrolids were separated using a reverse-phase C18 ($250\;mm{\times}4.6\;mm$, $5\;{\mu}m$) column and a gradient elution with mobile phases consisting of phosphate buffer (pH 2.5) and acetonitrile. Tylosin and tilmicosin were detected at 288 nm and spiramycin was detected at 232 nm. The average recovery percentage ranged between 83.0-90.2% for samples spiked with the three macrolids at 50 and 100 ng/g The validation results showed that the limit of detection (7 (spiramycin), 12 (tilmiconsin), 12 (tylosin) ng/g)) was under the regulatory tolerances and the linearity from calibration curves was satisfactory for determining the multi-residue of three macrolids in farm products. Monitoring samples were collected at the main cities in Korea as Seoul, Busan, Deajeon, Incheon, Deagu, and Gwangju. Microlide antibiotics were not detected in most samples.

• Journal of Life Science
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• v.20 no.12
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• pp.1896-1901
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• 2010

This study was conducted using quantitative real-time PCR using Lactobacilli as probiotics. Quantitative real-time PCR (RT PCR) was conducted via a method involving SYBR Green 1 and a probe. Plasmid DNA was cloned using the 16S-23S rRNA intergenic species region. Gene clones were diluted from $10^2$ to $10^{10}$. Standard curves were constructed via Ct values obtained from the results of Real-time PCR via the aforementioned SYBR Green 1 and probe method. Plasmid DNA was also cloned using the 16S-23S rRNA intergenic species region and the gene clones were diluted from $10^2$ to $10^{10}$ copy numbers via the probe method. Using RT PCR, a standard curve of plasmid DNA copy numbers was also determined. The slope value for the Y-axis intercept and $R^2$ value were measured as -3.346, 33.18, and 0.993, respectively, via the first method. For the second method, the slope value for the Y-axis intercept and $R^2$ were -3.321, 31.10 and 0.995, respectively. The PCR inhibitor could not express the detection curve at a copy number over $10^{10}$ via either method, owing to high DNA density. The DNA extract from probiotics was diluted without pre-culturing, and 16 products were amplified via both methods. The Ct value was 11.06~18.12 in the first method and 16.74~22.11 in the second method. Measured probiotics and log copy values were largely similar among the methods used. It was concluded that both methods are effective for analysis, but further research will be required to verify the optimal method.

• The Korean Journal of Nuclear Medicine
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• v.32 no.5
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• pp.414-424
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• 1998

Purpose: Cross-modality coregistration of positron emission tomography (PET) and magnetic resonance imaging (MR) could enhance the clinical information. In this study we propose a refined technique to improve the robustness of registration, and to implement more realistic visualization of the coregistered images. Materials and Methods: Using the sinogram of PET emission scan, we extracted the robust head boundary and used boundary-enhanced PET to coregister PET with MR. The pixels having 10% of maximum pixel value were considered as the boundary of sinogram. Boundary pixel values were exchanged with maximum value of sinogram. One hundred eighty boundary points were extracted at intervals of about 2 degree using simple threshold method from each slice of MR images. Best affined transformation between the two point sets was performed using least square fitting which should minimize the sum of Euclidean distance between the point sets. We reduced calculation time using pre-defined distance map. Finally we developed an automatic coregistration program using this boundary detection and surface matching technique. We designed a new weighted normalization technique to display the coregistered PET and MR images simultaneously. Results: Using our newly developed method, robust extraction of head boundary was possible and spatial registration was successfully performed. Mean displacement error was less than 2.0 mm. In visualization of coregistered images using weighted normalization method, structures shown in MR image could be realistically represented. Conclusion: Our refined technique could practically enhance the performance of automated three dimensional coregistration.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.1
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• pp.65-72
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• 2008

Pulse oximeter to monitor oxygen saturation during pediatric dental sedations enables early detection of hypoxemia. The purpose of this study was to monitor the hemoglobin oxygen saturation level and pulse rate of nonmedicated pediatric patients during routine restorative procedures to study the effect of procedure and treated jaw. We obtained data from 53 children treated at the Department of Pediatric Dentistry, Chonbuk national university hospital. Pulse rate and oxygen saturation were measured and recorded using pulse oximetry at each step of treatment. The results are as follows: 1. In non-anesthesia group, steep increase of pulse rate was observed during rubber dam application in the maxilla and during cavity preparation in the mandible. 2. In anesthesia group, pulse rate started to decrease after the rubber dam application in the maxilla, while its decrease observed since cavity preparation step in the mandible. 3. In non-anesthesia group, oxygen saturation level was relatively constant during all steps in the maxilla, but in mandible, it was higher during operation compared to its pre and post operation baseline. 4. In anesthesia group, oxygen saturation level was observed at 99% level through all steps in both jaw groups, and there was no statistical significance between the maxilla and the mandible groups(p>0.05). The purpose of this study was to evaluate the effect of routine dental treatment on the pulse rate and oxygen saturation level in nonmedicated pediatric patients during routine restorative procedures in the maxilla and mandible.

• Radiation Oncology Journal
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• v.28 no.3
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• pp.141-146
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• 2010

Purpose: We examined the radioprotective effects of 5-androstendiol (5-AED), a natural hormone produced in the reticularis of the adrenal cortex, as a result of intestinal damage in gamma-irradiated C3H/HeN mice. Materials and Methods: Thirty mice (C3H/HeN) were divided into three groups; 1) non-irradiated control group, 2) irradiated group, and 3) 5-AED-treated group prior to irradiation. Next, 5-AED (50 mg/kg per body weight) was subcutaneously injected 24 hours before irradiation. The mice were whole-body irradiated with 10 Gy for the histological examination of jejunal crypt survival and the determination of the villus morphology including crypt depth, crypt size, number of villi, villus height, and length of basal lamina, as well as 5 Gy for the detection of apoptosis. Results: The 5-AED pre-treated group significantly increased the survival of the jejunal crypt, compared to irradiation controls (p<0.05 vs. irradiation controls at 3.5 days after 10 Gy). The evaluation of morphological changes revealed that the administration of 5-AED reduced the radiation-induced intestinal damages such as villus shortening and increased length of the basal lamina of enterocytes (p<0.05 vs irradiation controls on 3.5 day after 10 Gy, respectively). The administration of 5-AED decreased the radiation-induced apoptosis in the intestinal crypt, with no significant difference between the vehicle and 5-AED at 12 hours after 5 Gy. Conclusion: The results of this study suggest that the administration of 5-AED has a protective effect on intestinal damage induced by $\gamma$-irradiation. In turn, these results suggest that 5-AED could be a useful candidate for radioprotection against intestinal mucosal injury following irradiation.

• Journal of environmental and Sanitary engineering
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• v.13 no.1
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• pp.123-134
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• 1998

The study was performed to investigate the differences among various evaluation criteria for noise-induced hearing loss(NIHL). The subjects were 100 workers who had received detailed audiometric examinations after the periodic annual examination for hearing loss. The evaluation criteria included were as follows: The criterion I was NIHL of 50dB or greater at 4,000Hz in either ear which is one of the legal requirements for determining occupational hearing loss in Korea. The criterion II was NIHL of 40dB or greater by 4-divided classification(a+b+c+d/4 at 500Hz(a), 1,000Hz(b), 2,000Hz(c), 4,000Hz(d)) which is also one of the legal requirements for determining occupational hearing loss in Korea. The criterion III was NIHL of 31dB of greater by 6-divided classification(a+2b+2c+d/6) which is the workers' compensation standard. The criterion IV was NIHL of 40dB or greater by 6-divided classification(a+2b+2c+d/6), the criterion used to prohibite workers to be employed in the noisy workplace. The criterion V was NIHL of 40dB or greater by 3-divided classification(a+b+c/3) which is the guideline of the Japanes Labour Department. The results were as follows; 1. The percentage of workers with NIHL by the criterion I was the highest(96%) and covered all workers with NIHL diagnosed by other criteria. Therefore, this criterion was the most sensitive one for early detection of NIHL among various evaluation criteria. 2. The percentage of workers with NIHL by the criterion II was 29% of the subjects, but all of them could be diagnosed as having NIHL by the criterion I and 33.1% of the NIHL by the criterion III could not be covered by the criterion II. Thus, this criterion was not considered suitable as an initial step for determining occupational hearing loss. 3. The percentage of workers with NIHL by the criterion III was 45% of the subjects. This percentage was 46.9% of the NIHL by the criterion I and was estimated to cover 3.6% of all noise exposed workers. 4. The percentage of workers with NIHL by the criterion IV was 28% of the subjects, but 37.8% of the NIHL by the criterion III and 70.8% of the NIHL by the criterion I were not covered by the criterion. Therefore, these workers could have been employed in the noisy workplaces. 5. Employed relocation which was one of the post management methods was an option in the criterion I in Korea and in the criterion V in Japan. The number of NIHL by the criterion I was 6.7times greater than that by the criterion V. Thus, although employee relocation was not used exclusively, many more workers with NIHL could have been relocated. In conclusion, this study revealed that the criteria being used for managing occupational hearing loss showed a lack uniformity among them. In addition, since these criteria are all relied on the total threshold shifts caused by the noise exposure at the time of hearing test with no consideration given to the past noise exposure history nor age, it can be said that they are not an effective tool for occupational hearing loss management. Since legal requirements are usually followed after being diagnosed as having NIHL, it is recommended that a uniform diagnostic criterion should be used to minimize confusion. Pre-employment hearing tests should also be utilized so as to managing occupational hearing loss after employment rather than being used as a legal roadblock of prohibiting workers with mild hearing loss from being employed. Thus, what is needed is an establishment of a rational criterion for occupational hearing loss management rather than for legal requirements.

• Journal of Genetic Medicine
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• v.4 no.1
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• pp.45-52
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• 2007

Purpose : A simple, rapid, and highly sensitive analytical method for Gb3 in plasma was developed without labor-ex tensive pre-treatment by electrospray ionization MS/ MS (ESI-MS/MS). Measurement of globotriaosy lceramide (Gb3, ceramide trihex oside) in plasma has clinical importance for monitoring after enzyme replacement therapy in Fabry disease patients. The disease is an X-linked lipid storage disorder that results from a deficiency of the enzyme ${\alpha}$-galactosidase A (${\alpha}$-Gal A). The lack of ${\alpha}$-Gal A causes an intracellular accumulation of glycosphingolipids, mainly Gb3. Methods : Only simple 50-fold dilution of plasma is necessary for the extraction and isolation of Gb3 in plasma. Gb3 in diluted plasma was dissolved in dioxane containing C17:0 Gb3 as an internal standard. After centrifugation it was directly injected and analyzed through guard column by in combination with multiple reaction monitoring mode of ESI-MS/MS. Results : Eight isoforms of Gb3 were completely resolved from plasma matrix. C16:0 Gb3 occupied 50% of total Gb3 as a major component in plasma. Linear relationship for Gb3 isoforms w as found in the range of 0.001-1.0 ${\mu}g$/mL. The limit of detection (S/N=3) was 0.001 ${\mu}g$/mL and limit of quantification was 0.01 ${\mu}g$/mL for C16:0 Gb3 with acceptable precision and accuracy. Correlation coefficient of calibration curves for 8 Gb3 isoforms ranged from 0.9678 to 0.9982. Conclusion : This quantitative method developed could be useful for rapid and sensitive 1st line Fabry disease screening, monitoring and/or diagnostic tool for Fabry disease.

• Journal of Food Hygiene and Safety
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• v.34 no.3
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• pp.283-289
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• 2019

This study was performed to monitor the residual pesticides in agricultural products used in school foodservice in the Gwangju metropolitan area. Risk assessment was also carried out based on the amount of agricultural products consumed. A total of 320 agricultural products supplied to schools in Gwangju were analyzed from 2015 to 2017. The pre-treatment and residual pesticide analysis of these products was conducted in accordance with the second method for multi-residue analysis of pesticides in the Korean food code. The hazard index was calculated by dividing the estimated daily intake (EDI) of pesticides by the acceptable daily intake (ADI). The linearity correlation coefficient for the calibration curve was 0.9923 to 1.0000, LOD 0.004 to 0.019 mg/kg, LOQ 0.012 to 0.057 mg/kg, and recovery was 79.1 to 100.2%. Residual pesticides were detected in 18 (5.6%) of 320 agricultural products used for school foodservice, and one sample of sweet potato stem (0.3%) exceeded the maximum residual limit (MRL). The detection frequency for chili peppers and bell peppers was higher than that for other agricultural products. The frequently-detected pesticides were boscalid and acetamiprid. These results showed that residual pesticide management is needed for chili pepper, bell pepper and sweet potato stem among agricultural products supplied to schools. The hazard index of bifenthrin in sweet potato stem showed the highest (64.18%), and the other pesticides were 0.03-8.23%. These results indicated that agricultural products supplied to schools in Gwangju were safe for consumption. To minimize the intake of residual pesticides, it is necessary to not only thoroughly wash agricultural products but to also ensure the expanded supply of products that are pesticide-free.

• Journal of Intelligence and Information Systems
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• v.20 no.2
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• pp.109-122
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• 2014

People are nowadays creating a tremendous amount of data on Social Network Service (SNS). In particular, the incorporation of SNS into mobile devices has resulted in massive amounts of data generation, thereby greatly influencing society. This is an unmatched phenomenon in history, and now we live in the Age of Big Data. SNS Data is defined as a condition of Big Data where the amount of data (volume), data input and output speeds (velocity), and the variety of data types (variety) are satisfied. If someone intends to discover the trend of an issue in SNS Big Data, this information can be used as a new important source for the creation of new values because this information covers the whole of society. In this study, a Twitter Issue Tracking System (TITS) is designed and established to meet the needs of analyzing SNS Big Data. TITS extracts issues from Twitter texts and visualizes them on the web. The proposed system provides the following four functions: (1) Provide the topic keyword set that corresponds to daily ranking; (2) Visualize the daily time series graph of a topic for the duration of a month; (3) Provide the importance of a topic through a treemap based on the score system and frequency; (4) Visualize the daily time-series graph of keywords by searching the keyword; The present study analyzes the Big Data generated by SNS in real time. SNS Big Data analysis requires various natural language processing techniques, including the removal of stop words, and noun extraction for processing various unrefined forms of unstructured data. In addition, such analysis requires the latest big data technology to process rapidly a large amount of real-time data, such as the Hadoop distributed system or NoSQL, which is an alternative to relational database. We built TITS based on Hadoop to optimize the processing of big data because Hadoop is designed to scale up from single node computing to thousands of machines. Furthermore, we use MongoDB, which is classified as a NoSQL database. In addition, MongoDB is an open source platform, document-oriented database that provides high performance, high availability, and automatic scaling. Unlike existing relational database, there are no schema or tables with MongoDB, and its most important goal is that of data accessibility and data processing performance. In the Age of Big Data, the visualization of Big Data is more attractive to the Big Data community because it helps analysts to examine such data easily and clearly. Therefore, TITS uses the d3.js library as a visualization tool. This library is designed for the purpose of creating Data Driven Documents that bind document object model (DOM) and any data; the interaction between data is easy and useful for managing real-time data stream with smooth animation. In addition, TITS uses a bootstrap made of pre-configured plug-in style sheets and JavaScript libraries to build a web system. The TITS Graphical User Interface (GUI) is designed using these libraries, and it is capable of detecting issues on Twitter in an easy and intuitive manner. The proposed work demonstrates the superiority of our issue detection techniques by matching detected issues with corresponding online news articles. The contributions of the present study are threefold. First, we suggest an alternative approach to real-time big data analysis, which has become an extremely important issue. Second, we apply a topic modeling technique that is used in various research areas, including Library and Information Science (LIS). Based on this, we can confirm the utility of storytelling and time series analysis. Third, we develop a web-based system, and make the system available for the real-time discovery of topics. The present study conducted experiments with nearly 150 million tweets in Korea during March 2013.