• Title/Summary/Keyword: methods of data analysis

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Monitoring of Residual Pesticides and Exposure Assessment of Olive Oil Products Sold on the Market (올리브유의 잔류농약 모니터링 및 노출량 조사)

  • Mi-Hui Son;Jae-Kwan Kim;You-Jin Lee;Ji-Eun Kim;Eun-Jin Baek;Byeong-Tae Kim;Seong-Nam Lee;Myoung-Ki Park;Yong-Bae Park
    • Journal of Food Hygiene and Safety
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    • v.38 no.4
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    • pp.211-216
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    • 2023
  • A total of 100 commercially available olive oil products were analyzed for 179 pesticide residues using gas chromatography-tandem mass spectrometry (GC/MS/MS). The olive oil samples were mixed with organic solvents, centrifuged and frozen to remove fat, and pesticide residues were analyzed using the "quick, easy, cheap, effective, rugged, and safe" (QuEChERS) method. The determination coefficient (R2) of the analysis method used in this study was ≥0.998. The detection limit of the method ranged 0.004-0.006 mg/kg and its quantitative limit ranged 0.012-0.017 mg/kg. The recovery rate (n=5) measured at the level ranging 0.01-0.02, 0.1, and 0.5 mg/kg ranged 66.8-119.5%. The relative standard deviation (RSD) was determined to be ≤5.7%, confirming that this method was suitable for the "Guidelines for Standard Procedures for Preparing Food Test Methods". The results showed that a total of 151 pesticides (including difenoconazole, deltamethrin, oxyfluorfen, kresoxim-methyl, phosmet, pyrimethanil, tebuconazole, and trifloxystrobin) were detected in 64 of the 100 olive oil products. The detection range of these pesticide residues was 0.01-0.30 mg/kg. The percentage acceptable daily intake (%ADI) of the pesticides calculated using ADI and estimated daily intake (EDI) was 0.0001-0.1346, indicating that the detected pesticides were present at safe levels. This study provides basic data for securing the safety of olive oil products by monitoring pesticide residues in commercially available oilve oil products. Collectively, the analysis method used in this study can be used as a method to analyze residual pesticides in edible oils.

Feasibility of Pediatric Low-Dose Facial CT Reconstructed with Filtered Back Projection Using Adequate Kernels (필터보정역투영과 적절한 커널을 이용한 소아 저선량 안면 컴퓨터단층촬영의 시행 가능성)

  • Hye Ji;Sun Kyoung You;Jeong Eun Lee;So Mi Lee;Hyun-Hae Cho;Joon Young Ohm
    • Journal of the Korean Society of Radiology
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    • v.83 no.3
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    • pp.669-679
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    • 2022
  • Purpose To evaluate the feasibility of pediatric low-dose facial CT reconstructed with filtered back projection (FBP) using adequate kernels. Materials and Methods We retrospectively reviewed the clinical and imaging data of children aged < 10 years who underwent facial CT at our emergency department. The patients were divided into two groups: low-dose CT (LDCT; Group A, n = 73) with a fixed 80-kVp tube potential and automatic tube current modulation (ATCM) and standard-dose CT (SDCT; Group B, n = 40) with a fixed 120-kVp tube potential and ATCM. All images were reconstructed with FBP using bone and soft tissue kernels in Group A and only bone kernel in Group B. The groups were compared in terms of image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). Two radiologists subjectively scored the overall image quality of bony and soft tissue structures. The CT dose index volume and dose-length product were recorded. Results Image noise was higher in Group A than in Group B in bone kernel images (p < 0.001). Group A using a soft tissue kernel showed the highest SNR and CNR for all soft tissue structures (all p < 0.001). In the qualitative analysis of bony structures, Group A scores were found to be similar to or higher than Group B scores on comparing bone kernel images. In the qualitative analysis of soft tissue structures, there was no significant difference between Group A using a soft tissue kernel and Group B using a bone kernel with a soft tissue window setting (p > 0.05). Group A showed a 76.9% reduction in radiation dose compared to Group B (3.2 ± 0.2 mGy vs. 13.9 ± 1.5 mGy; p < 0.001). Conclusion The addition of a soft tissue kernel image to conventional CT reconstructed with FBP enables the use of pediatric low-dose facial CT protocol while maintaining image quality.

The Effects of Trunk Stabilization Training on a Stroke Patient's Postural Control and Activities of Daily Living: A Sing Subject Design (뇌졸중 환자의 체간안정화 훈련이 자세조절과 일상생활동작에 미치는 영향: 단일사례연구)

  • Nam, Ju-Hyeon;Shim, Gyeong-Bo;Gwak, Seong-Won
    • The Journal of Korean society of community based occupational therapy
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    • v.4 no.1
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    • pp.75-84
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    • 2014
  • Objective : This study intends to suggest an effective clinical intervention method for stroke patients by applying a trunk stabilization training program to a single stroke patient and investigating and analyzing the effects of the program on postural control and activities of daily living. Methods : The subject of this study was a 75 year-old female stroke patient hospitalized in C Hospital located in Gyeongju, Gyeongsangbuk-do. As for the research design, A-B-A reversal design was used with a single subject design; and the research period was a total of five weeks from April 21, 2014 to May 23, 2014. As for the research process, a total of 15 sessions were carried out including three sessions of baseline(A), nine sessions of an intervention period(B), and three sessions of maintenance(A'); and the trunk stabilization program was applied during the intervention period. To evaluate the participant's postural control and activities of living life, the Postural Assessment Scale for Stroke(PASS) and the modified Barthel Index(MBI) were used. Visual analysis was used in which collected data were plotted on a graph, using Microsoft Office Excel 2013. Results : In the postural control test, the mean scores improved from 11.7 in the baseline phase to 14.8 in the intervention phase and 15.3 in the maintenance phase. In the evaluation of activities of daily living, the score improved from 66(medium dependence) during the baseline period to 80(low dependence) after intervention and at the maintenance phase. Conclusion : It was found that the trunk stabilization training program showed effects on the stroke patient's postural control or alignment, and furthermore a beneficial improvement in the patient's performing the activities of daily living, as well.

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Analysis of Structural Types and Design Factors for Fruit Tree Greenhouses (과수재배용 온실의 구조유형과 설계요소 분석)

  • Nam, Sang-Woon;Ko, Gi-Hyuk
    • Journal of Bio-Environment Control
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    • v.22 no.1
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    • pp.27-33
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    • 2013
  • In order to provide basic data for the development of a controlled environment cultivation system and standardization of the structures, structural status and improvement methods were investigated for the fruit tree greenhouses of grape, pear, and peach. The greenhouses for citrus and grape cultivation are increasing while pear and persimmon greenhouses are gradually decreasing due to the advance of storage facilities. In the future, greenhouse cultivation will expand for the fruit trees which are more effective in cultivation under rain shelter and are low in storage capability. Fruit tree greenhouses were mostly complying with standards of farm supply type models except for a pear greenhouse and a large single-span peach greenhouse. It showed that there was no greenhouse specialized in each species of fruit tree. Frame members of the fruit tree greenhouses were mostly complying with standards of the farm supply type model or the disaster tolerance type model published by MIFAFF and RDA. In most cases, the concrete foundations were used. The pear greenhouse built with the column of larger cross section than the disaster tolerance type. The pear greenhouse had also a special type of foundation with the steel plate welded at the bottom of columns and buried in the ground. As the results of the structural safety analysis of the fruit tree greenhouses, the grape greenhouses in Gimcheon and Cheonan and the peach greenhouses in Namwon and Cheonan appeared to be vulnerable for snow load whereas the peach greenhouse in Namwon was not safe enough to withstand wind load. The peach greenhouse converted from a vegetable growing facility turned out to be unsafe for both snow and wind loads. Considering the shape, height and planting space of fruit tree, the appropriate size of greenhouses was suggested that the grape greenhouse be 7.0~8.0 m wide and 2.5~2.8 m high for eaves, while 6.0~7.0 m wide and 3.0~3.3 m of eaves height for the pear and peach greenhouses.

A comparative analysis of gas and liquid phase standard spiked solid sorbent tubes for the determination of volatile organic compounds in indoor air by TD-GC/MS (열탈착/저온농축-GC/MS에 의한 실내공기 중 휘발성 유기화합물 정량용 기체상 및 액체상 표준물질 첨가한 고체 흡착관의 비교 분석)

  • Lim, Hyun-Woo;Jung, Sung-Won;Kang, Chul-Ho;Park, Jin-Sook;Park, Byeong Moo;Choi, Yong-Wook
    • Analytical Science and Technology
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    • v.26 no.4
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    • pp.287-297
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    • 2013
  • The optimization of analytical method for the thermal desorption of seven VOCs (volatile organic compounds) by TD-GC/MS (thermal desorption-gas chromatograph-mass spectrometer) with solid phase sorbent tube, and comparative analysis for the determination of VOCs plotted by standard sorbent tubes prepared using both gas phase and liquid phase materials were investigated. The result of paired t-test showed that a liquid phase standard sorbent tube method was in agreement with a gas phase standard sorbent tube method for six species of VOCs including benzene, toluene, ethylbenzene, o-, m-, and p-xylene except for styrene at the significance level (${\alpha}=0.01$), while the 15.6% of difference in response factor between both of gas phase and liquid phase standard plotting for the determination of styrene showed that both methods were significantly different at the significance level. Therefore, the liquid phase standard plotting method was employed to reduce erroneous data for the determination of styrene including BTEX. Under the optimized analytical method by liquid phase standard sorbent tube, recovery was between $100{\pm}5%$ for 7 species of VOCs, reproducibility ranged from 0.3 to 7.7%, and method detection limit (MDL) ranged from $0.01{\mu}g/m^3$ for o-xylene to $0.27{\mu}g/m^3$ for toluene. The optimized standard method was applied to determine VOCs VOCs from indoor air of of dormitory, one bedroom apartment, and a new car.

Effect of Development and Application of Teaching-Learning Materials and Plan using Persimmon juice Dyeing on the Traditional Clothing Life-Culture Education (감즙염색을 이용한 학습자료와 교수-학습과정안 개발 및 적용이 전통 의생활문화 교육에 미치는 효과)

  • Park, Soonja;Yoo, Jiyeon
    • Journal of Korean Home Economics Education Association
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    • v.25 no.1
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    • pp.79-94
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    • 2013
  • In this study, the teaching-learning materials and the plan using persimmon juice dyeing, which is one of the traditional natural dyeing methods of Korea, were developed for the purpose of inspiring further awareness of our traditional clothing life-culture. A questionnaire was designed to make a survey on the educational effect, and t-test and Kruscal-Wallis test were conducted to test the significant differences between pre- and post-lessons. A correlation analysis between culture awareness and its education awareness was also done. These prototypes were applied to high school Technology Home Economics classes under the theme, 'Making living goods with persimmon juice dyed fabrics'. Examining the changes in students' awareness of traditional images, and changes in their interest and attitude towards learning in those classes led to the following results. First, as a result of applying LT cooperative learning in order for an understanding of the formation of clothing life-culture and the process of persimmon juice dyeing, many original handicrafts with modern sense were created. Second, a comparative analysis between pre- and post-lessons on the change in students' degree of awareness of traditional clothing life-culture and its education showed that students' awareness had risen after the class; the data was collected from three separate sample groups which had been clustered according to their initial degree of awareness, i.e. high, middle, and low, and the group that scored the lowest before the class showed the greatest improvement. Third, feedback surveys on 'Making living goods with persimmon juice dyed fabrics' classes returned with scores greater than 'moderate', thus revealing that the students' concern and interest towards traditional clothing life-culture hae been enhanced through the class experience. Their attitude had also become more positive. Fourth, since learners with more awareness of the traditional clothing life-culture also showed more awareness of the need for an education designed to promote the culture, a positive correlation between the two had been found. As explained above, the teaching-learning materials and the plan that had been developed for this study has caused a deeper understanding of the value and significance of the traditional natural dyeing and clothing life-culture, and has therefore brought about an educational effect that powers idea creation.

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The Effect of Intravenous Contrast on SUV Value in $^{18}F$-FDG PET/CT using Diagnostic High Energy CT (진단용 고선량 CT를 이용한 $^{18}F$-FDG PET/CT 촬영시 정맥 조영제가 SUV 값에 미치는 영향)

  • Jeong, Young-Jin;Kang, Do-Young
    • Nuclear Medicine and Molecular Imaging
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    • v.40 no.3
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    • pp.169-176
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    • 2006
  • Purpose: According to the development of CT scanner in PET/CT system, the role of CT unit as a diagnostic tool has been more important. To improve the diagnostic ability of CT scanner, it is a key aspect that CT scanning has to be performed with high dose energy and intravenous (IV) contrast. So we investigated the effect of IV contrast media on the maximum SUV (maxSUV) of normal tissues and pathologic lesions using PET/CT scanner with high dose CT scanning. Materials & Methods: The study enrolled 13 patients who required PET/CT evaluation. At first, the patients were performed whole body non-contrast CT (NCCT-120 kVp, 130 mAs) scan. Then contrast enhanced CT (CECT) scan was performed immediately. Finally PET scan was followed. The PET omission data were reconstructed twice, once with the NCCT and again with the CECT. We measured the maxSUV of 10 different body regions that were considered as normal in ail patients. Also pathologic lesions were investigated. Results: There were not seen focal artifacts in PET images based on CT with IV contrast agent. Firstly, 130 normal regions in 13 patients were evaluated. The maxSUV was significantly different between two PET images (p<0.00)). The maxSUV was $1.1{\pm}0.5$ in PET images with CECT-corrected attenuation and $1.0{\pm}0.5$ in PET images with NCCI-corrected attenuation. The limit of agreement was $0.1{\pm}0.3$ in Bland-Altman analysis. Especially there were significant differences in 6 of 10 regions, apex and base of the right lung, ascending aorta, segment 6 & segment 8 of the liver and spleen (p<0.05). Secondly, 39 pathologic lesions were evaluated. The maxSUV was significantly different between two PET images (p<0.001). The maxSUV was $4.7{\pm}2.0$ in PET images with CECT-corrected attenuation and $4.4{\pm}2.0$ in PET images with NCCT-corrected attenuation. The limit of agreement was $0.4{\pm}0.8$ in Bland-Altman analysis. Conclusion: Although there were increases of maxSUVs in the PET images based on CT with IV contrast agent, it was very narrow in the range of limit of agreement. So there was no significant effect to clinical interpretation for PET images that were corrected attenuation with high dose CT using IV contrast.

Effects of Chronic and Acute Stress on Clusterin Secretion of the Rat Submandibular Gland (급만성 스트레스가 백서 악하선의 Clusterin 분비에 미치는 영향)

  • Jin, Sang-Bae;Chun, Yang-Hyun;Hong, Jung-Pyo
    • Journal of Oral Medicine and Pain
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    • v.31 no.1
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    • pp.79-89
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    • 2006
  • The aim of this study is to know how the rat submandibular gland changes under various emotional stress condition, using molecular biological methods. Restraint and chronic unpredictable mild stress (CUMS) experiment is conducted on fifty one 7-week old Sprague-Dawley rats (restraint stress experiment: 21, CUMS: 30). The rats were sacrificed, the submandibular glands were excised immediately at certain time, and examined by the use of immunohistochemistry and western blotting. In CUMS experiment, sucrose preference test, water intake change, weight change were implemented at 1 week interval for the experimental period The results are as follows: 1. The number of clusterin-secreting cells of restraint stress group compared to control group showed significantly decreasing tendency in all experimental groups except for the 1st hour group (p<0.001 in the 9th, 24th, 72nd, 120th, and 168th hour group). 2. The number of clusterin-secreting cells of CUMS group compared to control group showed significantly increasing tendency in the 2nd week group (p<0.01), and significantly decreasing tendency in the 4th and 5th week group (p<0.001). 3. Sucrose preference test in CUMS experiment showed significant difference between the 5th week experimental group and control group (p<0.01). 4. Weight change in CUMS experiment showed significant difference between the 5th week experimental group and control group (p<0.01), but water intake change didn't show significant difference compared to control group. 5. In western blot analysis, clusterin expression was decreased on a gradual basis in due time compared to the control group in the restraint stress group. As for CUMS group (chronic unpredictable mild stress group), it was increased till the 2nd week and decreased till the 5th week after that, which is similar to immunohistochemical analysis result and the decreasing tendency of sucrose preference and weigh changes. Through the test, it was proved that expression of clusterin in saliva glands decreases after receiving either acute or chronic stress, indicating relation with depression caused by chronic stress. Unlike other data, however, apoptotic tendency was hardly found in tissues. Diverse possibilities could be suggested on that: first, the stress was not enough to expedite apoptosis; second, apoptosis-related protein was already being secreted though not detected with microscope; third, clusterin, a major secretion molecule of saliva, decreased with saliva's malfunction due to stress. In the respect, it will be necessary to examine proteins expressed in case of cell death or other heat-shock proteins at the same time, in order to see whether any cellular change or death is caused by decreasing clusterin under high stress, and whether the original state is restored as time goes by under mild stress, through longer-term tests using even higher acute stress.

Characterization of compounds and quantitative analysis of oleuropein in commercial olive leaf extracts (상업용 올리브 잎 추출물의 화합물 특성과 이들의 oleuropein 함량 비교분석)

  • Park, Mi Hyeon;Kim, Doo-Young;Arbianto, Alfan Danny;Kim, Jung-Hee;Lee, Seong Mi;Ryu, Hyung Won;Oh, Sei-Ryang
    • Journal of Applied Biological Chemistry
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    • v.64 no.2
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    • pp.113-119
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    • 2021
  • Olive (Olea europaea L.) leaves, a raw material for health functional foods and cosmetics have abundant polyphenols including oleuropein (major bioactive compound) with various biological activities: antioxidant, antibacterial, antiviral, anticancer activity, and inhibit platelet activation. Oleuropein has been reported as skin protectant, antioxidant, anti-ageing, anti-cancer, anti-inflammation, anti-atherogenic, anti-viral, and anti-microbial activity. Despite oleuropein is the important compound in olive leaves, there is still no quantitative approach to reveal oleuropein content in commercial products. Therefore, a validated method of analysis has to develop for oleuropein. In this study, the components and oleuropein content in 10 types of products were analyzed using a developed method with ultra-performance liquid chromatography to quadrupole time-of-flight mass spectrometry, charge of aerosol detector, and photodiode array. The total of 18 compounds including iridoids (1, 3, 4, 14, and 16-18), coumarin (2), phenylethanoids (5, 9, and 11), flavonoids (6-8, 10, 12, and 13), lignan (15), were tentatively identified in the leaves extract based high resolution mass spectrometry data, and the content of oleuropein in each product was almost identical between two detection methods. The oleuropein in three commercial product (A, G, H) was contained more over the suggested content, and it of five products (B, E, H, I, J) were analyzed within 5-10% error range. However, the two products (C, D) were found far lower than suggested contents. This study provides that analytical results of oleuropein could be a potential information for the quality control of leaf extract for a manufactured functional food.

Application of Flux Average Discharge Equation to Assess the Submarine Fresh Groundwater Discharge in a Coastal Aquifer (연안 대수층의 해저 담지하수 유출량 산정을 위한 유량 평균 유출량 방정식의 적용)

  • Il Hwan Kim;Min-Gyu Kim;Il-Moon Chung;Gyo-Cheol Jeong;Sunwoo Chang
    • The Journal of Engineering Geology
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    • v.33 no.1
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    • pp.105-119
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    • 2023
  • Water supply is decreasing due to climate change, and coastal and island regions are highly dependent on groundwater, reducing the amount of available water. For sustainable water supply in coastal and island regions, it is necessary to accurately diagnose the current condition and efficiently distribute and manage water. For a precise analysis of the groundwater flow in the coastal island region, submarine fresh groundwater discharge was calculated for the Seongsan basin in the eastern part of Jeju Island. Two methods were used to estimate the thickness of the fresh groundwater. One method employed vertical interpolation of measured electrical conductivity in a multi depth monitoring well; the other used theoretical Ghyben-Herzberg ratio. The value using the Ghyben-Herzberg ratio makes it impossible to accurately estimate the changing salt-saltwater interface, and the value analyzed by electrical conductivity can represent the current state of the freshwater-saltwater interface. Observed parameter was distributed on a virtual grid. The average of submarine fresh groundwater discharge fluxes for the virtual grid was determined as the watershed's representative flux. The submarine fresh groundwater discharge and flux distribution by year were also calculated at the basin scale. The method using electrical conductivity estimated the submarine fresh groundwater discharge from 2018 to 2020 to be 6.27 × 106 m3/year; the method using the Ghyben-Herzberg ratio estimated a discharge of 10.87 × 106 m3/year. The results presented in this study can be used as basis data for policies that determine sustainable water supply by using precise water budget analysis in coastal and island areas.