• Nuclear Medicine and Molecular Imaging
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• v.41 no.6
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• pp.553-560
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• 2007

Purpose: We evaluated the standard uptake value (SUV) of F-18 FDG at PET/CT for differentiation of benign from malignant tumor in primary musculoskeletal tumors. Materials and Methods: Forty-six tumors (11 benign and 12 malignant soft tissue tumors, 9 benign and 14 malignant bone tumors) were examined with F-18 FDG PET/CT (Discovery ST, GE) prior to tissue diagnosis. The maxSUV(maximum value of SUV) were calculated and compared between benign and malignant lesions. The lesion analysis was based on the transverse whole body image. The maxSUV with cutoff of 4.1 was used in distinguishing benign from malignant soft tissue tumor and 3.05 was used in bone tumor by ROC curve. Results: There was a statistically significant difference in maxSUV between benign (n=11; maxSUV $3.4{\pm}3.2$) and malignant (n=12; maxSUV $14.8{\pm}12.2$) lesions in soft tissue tumor (p=0.001). Between benign bone tumor (n=9; maxSUV $5.4{\pm}4.0$) and malignant bone tumor (n=14; maxSUV $7.3{\pm}3.2$), there was not a significant difference in maxSUV. The sensitivity and specificity for differentiating malignant from benign soft tissue tumor was 83% and 91%, respectively. There were four false positive malignant bone tumor cases to include fibrous dysplasia, Langerhans-cell histiocytosis (n=2) and osteoid osteoma. Also, one false positive case of malignant soft tissue tumor was nodular fasciitis. Conclusion: The maxSUV was useful for differentiation of benign from malignant lesion in primary soft tissue tumors. In bone tumor, the low maxSUV correlated well with benign lesions but high maxSUV did not always mean malignancy.

• Journal of the Korean association of regional geographers
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• v.6 no.2
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• pp.83-96
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• 2000

Erosional basins formed in middle and upper reaches of Korean great rivers have been main life space of local small and middle cities, but previous studies on erosional basins are widely apart from residents' life and are in shortage with the endeavor to elucidate the man and environment relationship. This paper analyzes the factors and the modes of land-use changes of hills in the erosional basin. In this paper four erosional basins with different geological conditions are selected to elucidate the effect of geological factor(Geochang: granite, Chogye: metamorphic rock, Angye: gravelly sedimentary rock, Maseong: limestone). And the distribution of land use on the transverse and longitudinal cross-section map of the hill is described. The landscape of erosional basin is consisted of surrounding mountains, hills, dissected valleys, and incoming river's floodplain. Dissected valleys and incoming river's floodplain were reclaimed early as paddy field and hills have been used as woodland up to recently. Residents have a new appreciation of hills as a productive hill out of a traditional holy space[mountain] by influence of capitalistic thought that 'natural environment is a sort of productive resource'. Population increase is the another pressure of hill reclamation. The modes of landscape changes due to natural conditions are as follow: (1) In Geochang basin with dense tectolineament spacing, the gentle part of hill is used as field, orchard and agricultural-industrial complex site and the steep part is as woodland. (2) Hills in Angye basin with sparse tectolineament spacing are relatively flat because of maintaining a part of original denudational surface, and are used as orchids, field, paddy fields and agricultural-industrial complex site. The dissection valleys between hills are gentle concave and are used as paddy fields. (3) Hills in Maseong basin are wide and flat, and are used as fields, orchards, and agricultural-industrial complex site. (4) Because hills in Chogye basin, a closed type, are weared by affluents and are narrow and short. Hills are used as woodland and wide dissected valleys are reclaimed as paddy fields.

• Applied Microscopy
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• v.29 no.2
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• pp.211-221
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• 1999

The ultrastructural changes of cuticular surface, excretory and digestive organs of Anisakis simplex larvae chronologically recovered from experimental cats were observed with a SEM and TEM. The larva recovered from an experimental cat at 3 days post-infection (PI) retained the cuticular surface with regular transverse striations and a longitudinal groove on the lateral side of body. This finding suggests that the molting of the 3rd stage larva of A. simplex to 4th one occurred from the 3rd day after infection in cats. The excretory organ (renette cell) consisted of a large cell with numerous ductules ramified from the main duct, mitochondria and secretory granules in cytoplasm. Secretory granules in the renette cell of larvae recovered at 24 hours PI were round whereas those of control and larvae recovered at 6 hours PI were amorphous. Muscular esophagus and ventriculus also retained many secretory granules in the cytoplasm. The secretory granules in these organs of larvae recovered at $6\sim24$ hours PI were electron-dense and widely distributed whereas those of control worm were packed in a pocket and retained various electron densities. In the cytoplasm of intestinal epithelial cells, numerous fine glycogen particles and mitochondria were distributed. The chronological changes of secretory granules in renette cell, muscular esophagus and ventriculus seem to be related with the worm penetration into host tissue.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.3
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• pp.99-107
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• 1965

Thirteen varieties of hemp, Cannabinus sativa L., consisting of four Italian, one Japanese and eight local varieties were used in the study on the fiber content and a satisfactory selection for the higher-fiber-yielding plants. In addition, the relationship among fiber contents at the ball setting stage, and at the maturity stage, primary fiber content, and total fiber content were determined. The results of the study are summarized as follow: 1. Fiber weight of the matured male plant expressed as percentage of the fiber weight to dried stems varied from 12.09 to 26.71 percent for the Italian varieties, 14.25% for the Japanese variety and ranged from 6.59 to 16.79 for the local varieties. It was shown that on the average, Italian varieties contained more fiber compared with the other varieties. 2. On the same basis, the average percent age of fiber for Italian male plants was 20.77 while it was 20.96 for female plants. For the Japanese variety, similar figures were 14.24 for male plants and 15.43 for female plants. By comparison, the average percent fiber for the male plants of Korean varieties was only 10.34 but averaged 16.79 for female plants. In this experiment, female plants contained a greater percentage of fiber than male plants. 3. Statistically significant correlations were obtained between fiber content at the ball setting stage and fiber content of the mature plant. The correlation coefficient was r=0.942＊＊, while the regression equation was Y=0.28+1.03X. These data indicate that plant. selection by early testing at the ball setting stage is an effective method for the improvement of fiber content. 4. The correlation between primary fiber content and total fiber content was r=0.913＊＊, with a regression equation of Y=12.01+1.20X. It should thus be possible to obtain plants of higher total fiber content at maturity by the selection of plants which have a higher content of primary fiber at the ball setting stage. 5. From a study of the transverse sections from the hemp plant it was shown that Italian varieties have wide bands of primary and secondary fibers with narrow areas of woody material, while both Korean local varieties and Japanese varieties have narrow bands of primary and secondary fiber and wide areas of woody material. For hemp improvement, it is certain that a variety which has a narrow area of woody substances and wide area of fiber in its stem should be selected.

• The Korean Journal of Nuclear Medicine Technology
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• v.19 no.1
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• pp.3-11
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• 2015

Purpose It is hard to obtain high quality images of knee and T.M joint because of a lot of soft tissues in the knee and T.M joint area. Most conventional system for high resolution scintigraphy was used by 4 mm aperture pinhole collimator. Performance comparison of high-resolution pinhole SPECT for Micro deluxe phantom using conventional system. the aim of this study is to evaluate performance of each aperture according to the diameter size and the usefulness of 24-hour delayed bone scintigraphy. Materials and Methods In this study 6 mm, 8 mm diameter pinhole collimators were mounted on Siemens E.CAM systems. In order to evaluate performance evaluation of each aperture and Micro Deluxe phantom was used for performance comparison of conventional SPECT system, Projection data were obtained with 9 degree increment per 30 second. Transverse images were reconstructed using dedicated OSEM algorithm with recovery of detector blurring. $^{99m}Tc-HDP$ source was used for 24-hour delayed bone scintigraphy. Results The knee joint images obtained with 24-hour delay were improved more than those obtained with 3-hour delay in our study. The 6 mm and 8 mm pinhole collimators FWHM have improved by 28% SNR and Uniformity have improved by 35%, Contrast has improved by 7% in 24-hour delayed knee joint image. While in 24-hour delayed T.M joint image of the 6 mm and 8 mm pinhole collimators FWHM have decreased by 60% SNR has decreased by 20% and Uniformity has decreased by 25%, Contrast has decreased significantly. Conclusion Pinhole collimators with 6 mm and 8 mm diameter could offer a superior performance for 24-hour delayed bone scintigraphy. The use of 24-hour delayed image provides additional benefits for pinhole scintigraphy of knee joint. Therefore, we expect that it is useful for precise diagnosis of knee joint and it is applicable to others joint imaging.

• The Korean Journal of Nuclear Medicine Technology
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• v.21 no.1
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• pp.70-75
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• 2017

Purpose Radioactive iodine thyroid uptake (RAIU) rate is an examination which determines and seeks about general functions of thyroid gland. The size of thyroid gland is normally different between each person, also patients having thyroid diseases have had a variety of size of thyroid gland compared with others. The purpose of this study will investigate about the counting rate which is effected by the geometric factors through the length and volume changes of the source in RAIU rate. Materials and Methods I-131 185 kBq ($5{\mu}Ci$) were placed in a cylindrical phantom of 0.5 cm, 1 cm, 1.5 cm, and 3 cm in diameter, respectively, and saline was added to gradually increase the length by 1 cm in the horizontal and vertical directions to give a change in volume. The source was measured 20 times for 20 seconds from a distance of 25 cm to $364.4keV{\pm}20%$ energy ROI with Captus 3000 thyroid uptake system (Capintec, NJ, USA). Results When the source was located in the transverse direction of the detector, the consequence of one-way ANOVA is that even though the length of source is increased each diameter, there is mostly no significant difference. When the source was located in the longitudinal direction and the counting rate of length 1 cm at all diameter is set to 100%, the average is 92.57% for length 2 cm, 86.1% for 3 cm, 80.69% for 4 cm, 74.82% for 5 cm, and 69.68% at 6 cm. Conclusion According to this study, it is expected that the gap of RAIU rate has been depended on the thickness of thyroid gland as well as the diameter of the beaker. We know that the change of the volume with the increase of the length of the source had less effect on the change of the counting rate. Thus, in order to reduce the error in the measurement of the counting rate with the thyroid uptake rate equipment, an accurate counting rate can be relatively measured if the counting rate which is measured is corrected by thickness or the distance between the thyroid and the thyroid uptake rate equipment is changed.

• Journal of agriculture & life science
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• v.46 no.6
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• pp.17-24
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• 2012

Soil types for cultivated crops are approximately compose of volcanic ash soils for black(21%) and dark brown soils(41%), and non-volcanic ash soil of red-yellow soil(17%) in Jeju Island. The effects of these soils on fruit qualities of kiwifruit 'Jecy Gold'(Actinidia chinensis cv. Jecy Gold) were investigated in non-heating plastic house. Soil moisture potential was the lowest in the red-yellow soil during fruit growth. However, transverse diameter of fruit in the red-yellow soil was tends to be smaller than in volcanic ash soils, but longitudinal length of fruit was not shown difference by soil types during fruit maturation. Soluble solids in fruit was not differed by soil types until 140 days after of anthesis, after that the red-yellow soil was the highest. No difference on acid contents and hardness of fruit by soil types. Fructose, glucose and sucrose contents in harvested fruit were $4.45{\pm}2.08$, $5.43{\pm}1.13$, and $2.40{\pm}0.40%$ for the red-yellow soil, $2.51{\pm}0.55$, $3.52{\pm}0.86$, and $0.79{\pm}0.33%$ for the black soil and $2.54{\pm}0.47$, $3.52{\pm}0.73$, and $0.73{\pm}0.38%$ for the dark brown soil, respectively. These results show that soluble solid and free sugars in fruit were affected by soil types. It is estimated that soil moisture was rapidly drought in the red-yellow soil of non-volcanic ash soil than in the black and dark brown soils of volcanic ash soil.

• Journal of Environmental Impact Assessment
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• v.27 no.6
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• pp.548-561
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• 2018

The objectives of this study were to construct a three-dimensional (3D) hydrodynamic and water quality model (EFDC) for the river reach between the Daecheong dam and the Sejong weir, which are directly affected by Gap and Miho streams located in the middle of the Geum River, and to evaluate the trophic status and water quality improvement effect according to the flow control and pollutant load reduction scenarios. The EFDC model was calibrated with the field data including waterlevel, temperature and water quality collected from September, 2012 to April, 2013. The model showed a good agreement with the field data and adequately replicated the spatial and temporal variations of water surface elevation, temperature and water quality. Especially, it was confirmed that spatial distributions of nutrients and algae biomass have wide variation of transverse direction. Also, from the analysis of algal growth limiting factor, it was found that phosphorous loadings from Gap and Miho streams to Sejong weir induce eutrophication and algal bloom. The scenario of pollutant load reduction from Gap and Miho streams showed a significant effect on the improvement of water quality; 4.7~18.2% for Chl-a, 5.4~21.9% for TP at Cheongwon-1 site, and 4.2~ 17.3% for Chl-a and 4.7~19.4% for TP at Yeongi site. In addition, the eutrophication index value, identifying the tropic status of the river, was improved. Meanwhile, flow control of Daecheong Dam and Sejong weir showed little effect on the improvement of water quality; 1.5~2.4% for Chl-a, 2.5~ 3.8% for TP at Cheongwon-1 site, and 1.2~2.1% for Chl-a and 0.9~1.5% for TP at Yeongi site. Therefore, improvement of the water quality in Gap and Miho streams is essential and a prerequirement to meet the target water quality level of the study area.

• Journal of the Korean Wood Science and Technology
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• v.49 no.5
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• pp.399-415
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• 2021

This study was conducted to suggest the optimal periods for planting and felling Larix kaempferi tree by monitoring its cambial activity period. In addition, the heat summation to induce the cambial activity of Larix kaempferi was investigated. The study sites were at Mt. Worak and Mt. Midong. After selecting 5 trees at Mt. Worak and Mt. Midong, the cambium samples were collected using a mini trephor with 2 mm diameter from April 7 to October 6, 2017 at Mt. Worak, and from April 7 to September 29, 2017 at Mt. Midong. After the collected cambium samples were embedded in PEG2000, transverse thin sections with a thickness of 10 to 15 ㎛ were prepared using a microtome. One Larix kaempferi sample from each site, Mt. Worak and Mt. Midong, in which the accurate monitoring of cambial activity was impossible due to the formation of traumatic resin canal, was excluded from the study. The observation of the initiation date of cambial activity under a light microscopy revealed that 2 specimens from Mt. Worak and 3 from Mt. Midong showed the initiation on April 28. The remaining 2 specimens of Mt. Worak and 1 specimen of Mt. Midong were initiated on May 4, which was a week later than the others. The heat summation that induced the initiation of cambial activity was 196.4-271.8 at Mt. Worak and 204.7-277.3 at Mt. Midong, which was similar. The termination of cambial activity occurred between August 4 and 25 at Mt. Worak, and between August 4 and September 1 at Mt. Midong. Based on the above results, it was found that the optimal planting period for Larix kaempferi in Mt. Worak and Mt. Midong was before April, about a month before the cambium activity, and the felling period was from October when the cambial activity was completely terminated.

• Journal of the Korean Society of Radiology
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• v.16 no.1
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• pp.67-75
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• 2022

The aim of this study is to establish a new QC method that can simultaneously evaluate the resolution of the x/y plane and the z-axis by producing a phantom that can reflect exposure and reconstruction parameter of MDCT system. It was used with Aquilion ONE(Cannon Medical System, Otawara, Japan), and the examination was scanned using of 120 kV, 260 mA, and the D-FOV of 300 mm². It produced new SSP phantom modules in which two aluminum plates inclined at 45° to a vertical axis and a transverse axis to evaluate high contrast resolution of x/y plane and z axis. And it changed factors such as the algorithm, distance from gantry iso-center. All images were reconstructed in five steps from 0.6 mm to 10.0 mm slice thickness to measure resolution of x/y plane and z-axis. The image data measured FWHM and FWTM using Profile tool of Aquarius iNtusion Edition ver. 4.4.13 P6 software(Terarecon, California, USA), and analysed SPQI and signal intensity by ImageJ program(v1.53n, National Institutes of Health, USA). It decreased by 4.09~11.99%, 4.12~35.52%, and 4.70~37.64% in slice thickness of 2.5 mm, 5.0 mm, and 10.0 mm for evaluating the high contrast resolution of x/y plane according to distance from gantry iso-center. Therefore, the high contrast resolution of the x/y plane decreased when the distance from the iso-center increased or the slice thickness increased. Additionally, the slice thicknesses of 2.5 mm, 5.0 mm, and 10.0 mm with a high algorithm increased 74.83, 15.18 and 81.25%. The FWHM was almost constant on the measured SSP graph for evaluating the accuracy of slice thickness which represents the resolution of x/y plane and z-axis, but it was measured to be higher than the nominal slice thickness set by user. The FWHM and FWTM of z-axis with axial scan mode tended to increase significantly as the distance increased from gantry iso-center than the helical mode. Particularly, the thinner slice thickness that increased error range compare with the nominal slice thickness. The SPQI increased with thick slice thickness, and that was closer to 90% in the helical scan than the axial scan. In conclusion, by producing a phantom suitable for MDCT detectors and capable of quantitative resolution evaluation, it can be used as a specific method in the management of research quality and management of outdated equipment. Thus, it is expected to contribute greatly to the discrimination of lesions in the field of CT imaging.