• Title/Summary/Keyword: volumetric

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Quantitative Evaluation of Liver Fibrosis on T1 Relaxometry in Comparison with Fibroscan (Fibroscan과 비교를 통한 T1 MR Relaxometry를 이용한 간섬유화의 정량적 평가)

  • Byeong Hak Sim;Suk Hee Heo;Sang Soo Shin;Seong Beom Cho;Yong Yeon Jeong
    • Journal of the Korean Society of Radiology
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    • v.81 no.2
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    • pp.365-378
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    • 2020
  • Purpose This study was performed to determine whether the T1 relaxation time of gadoxetic acid-enhanced liver MR imaging is useful for detecting and staging liver fibrosis in patients with chronic liver disease. Materials and Methods One hundred and three patients with suspected focal liver lesion underwent MR imaging and Fibroscan. Fibroscan was chosen as the reference standard for classifying liver fibrosis. T1 relaxation times were acquired before (preT1), 20 minutes after (postT1) contrast administration, and reduction rate of T1 relaxation time (rrT1) on transverse 3D VIBE (volumetric interpolated breath-hold examination) sequence using 3T MR imaging. The optimal cut-off values for the fibrosis staging were determined with ROC analysis. Results PreT1 and postT1 increased and rrT1 decreased constantly with increasing severity of liver fibrosis according to the METAVIR score (F0-F4). There were statistically significant differences between F2 and F3 in preT1 (F2, 836.0 ± 74.7 ms; F3, 888.6 ± 77.5 ms, p < 0.05) and between F3 and F4 in postT1 (F3, 309.0 ± 80.2 ms; F4, 406.6 ± 147.7 ms, p < 0.05) and rrT1 (F3, 65.4 ± 7.7%; F4, 57.3 ± 11.4%, p < 0.05). ROC analysis revealed that combination test (preT1 + postT1) was the best test for predicting liver fibrosis. Conclusion PreT1 and postT1 increased constantly with increasing severity of liver fibrosis. T1 mapping in gadoxetic acid-enhanced liver MR imaging could be a helpful complementary sequence to determine the liver fibrosis stage.

Adaptive Image Rescaling for Weakly Contrast-Enhanced Lesions in Dedicated Breast CT: A Phantom Study (약하게 조영증강된 병변의 유방 전용 CT 영상의 대조도 개선을 위한 적응적 영상 재조정 방법: 팬텀 연구)

  • Bitbyeol Kim;Ho Kyung Kim;Jinsung Kim;Yongkan Ki;Ji Hyeon Joo;Hosang Jeon;Dahl Park;Wontaek Kim;Jiho Nam;Dong Hyeon Kim
    • Journal of the Korean Society of Radiology
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    • v.82 no.6
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    • pp.1477-1492
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    • 2021
  • Purpose Dedicated breast CT is an emerging volumetric X-ray imaging modality for diagnosis that does not require any painful breast compression. To improve the detection rate of weakly enhanced lesions, an adaptive image rescaling (AIR) technique was proposed. Materials and Methods Two disks containing five identical holes and five holes of different diameters were scanned using 60/100 kVp to obtain single-energy CT (SECT), dual-energy CT (DECT), and AIR images. A piece of pork was also scanned as a subclinical trial. The image quality was evaluated using image contrast and contrast-to-noise ratio (CNR). The difference of imaging performances was confirmed using student's t test. Results Total mean image contrast of AIR (0.70) reached 74.5% of that of DECT (0.94) and was higher than that of SECT (0.22) by 318.2%. Total mean CNR of AIR (5.08) was 35.5% of that of SECT (14.30) and was higher than that of DECT (2.28) by 222.8%. A similar trend was observed in the subclinical study. Conclusion The results demonstrated superior image contrast of AIR over SECT, and its higher overall image quality compared to DECT with half the exposure. Therefore, AIR seems to have the potential to improve the detectability of lesions with dedicated breast CT.

Effects of Co-digestate application on the Soil Properties, Leachate and Growth Responses of Paddy Rice (통합혐기소화액의 시용이 벼 생육 및 논토양 환경에 미치는 영향)

  • Hong, Seung-Gil;Shin, Joung-Du;Kwon, Soon-Ik;Park, Woo-Kyun;Lee, Deog-Bae;Kim, Jeong-Gyu
    • Journal of the Korea Organic Resources Recycling Association
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    • v.18 no.4
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    • pp.31-37
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    • 2010
  • Livestock manures have a potential to be a valuable resource with an efficient treatment. In Korea, 42 million tons of livestock manure were generated in 2008, and 84 % of them were used for compost and liquid fertilizer production. Recently recycling of livestock manure for biogas production through anaerobic digestion is increasing, but its utilization in agriculture is still uncertified. In this study, there was applied co-digestate to the paddy for rice cultivation based on N supplement. Co-digestate was fertilizer fermented with pig slurry and food waste combined with the ratio of 70:30(v:v) in its volumetric basis. For assessing the safety of co-digestate, it was monitored the contents of co-digestate for seasonal variation, resulted in no potential harm to the soil and plant by heavy metals. The results showed that soil applied with co-digestate was increased in exchangeable potassium, copper and zinc mainly due to the high rate of pig slurry in co-digestate applied. Considering high salt content due to the combination with food waste, strict quality assurances are needed for safe application to arable land though it has valuable fertilizer nutrient. Leachate after treatment showed that the concentration of nitrate nitrogen washed out within two weeks. Considering the salt accumulation results in soil, it is highly recommended that the application rate of co-digestate should not exceed the crop fertilization rate based on N supplement. With these results, it was concluded that co-digestate could be used as an alternative fertilizer for chemical fertilizer. More study is needed for the long-term effects of co-digestate application on the soil and water environment.

Approach to the Extraction Method on Minerals of Ginseng Extract (추출조건(抽出條件)에 따른 인삼(人蔘)엑기스의 무기성분정량(無機成分定量)에 관(關)한 연구(硏究))

  • Cho, Han-Ok;Lee, Joong-Hwa;Cho, Sung-Hwan;Choi, Young-Hee
    • Korean Journal of Food Science and Technology
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    • v.8 no.2
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    • pp.95-106
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    • 1976
  • In order to investigate chemical components and mineral of ginseng cultivated in Korea and to establish an appropriate extraction method, the present work was carried out with Raw ginseng(SC), White ginseng(SB) and Ginseng tail(SA). The results determined could be summarized as follows : 1. Among the proximate components, moisture content of SC, SB and SA were 66.37%, 12.61% and 12.20% respectively. The content of crude ash in SA was the highest value of three kinds of ginseng root: SA 6.04%, SB 3.52% and SC 1.56%. The crude protein of Dried ginseng root(SA and SB) was about 12-14%, which was more than two times compared with that of SC(6.30%) The content of pure protein seemed to be in similar tendency with that of crude protein in three kinds of ginseng root: 2.26% in SC, 5.94% in SB and 5.76% in SA. There was no significant difference in the content of fat among the kinds of ginseng root. $(1.1{\sim}2.5%)$ 2. The highest Ginseng extract was obtained by use of Continuous extractor which is a modified Soxhlet apparatus for 60 hours extraction with 60-80% ethanol. 3. Ginseng and the above-mentioned ginseng extract (Ginseng tail extract: SAE, White Ginseng extract : SBE, Raw Ginseng extract: SCE) were analyzed by volumetric method for the determination of Chlorine and Calcium, by colorimetric method for that of Iron and Phosphorus, by Atomic Absorption Spectrophotometer for that of Zinc, Copper and Manganese. The results were as follows : 1. The content of phosphorus in SA, SB and SC were 1.818%, 1.362%, 0.713% respectively and phosphorus content in three kinds of extract were in low level (SAE: 0.03%, SBE: 0.063%, SCE: 0.036%) 2. In the Calcium content, SA, SB and SC were 0.147%, 0.238%, 0.126% and the Calcium contents of Ginseng extracts were 0.023%, 0.011% and 0.016%. The extraction ratio of Calcium from SA was the highest value (15.6%), while that in the case of SB was 4.6%. 3. The Chlorine content of SA was 0.11%, this was slightly higher than others(SB: 0.07%, SC: 0.09%) and extraction ratio of SA and SB were 36.4%, 67.1% while that of SC was 84.4%. 4. The Iron content of SA, SB and SC were 125ppm, 32.5ppm and 20ppm but extraction ratio was extremely low (SAE: 1.33%, SBE: 0.83%, SCE: 1.08%), 5. The Manganese content of SA, SB and SC were 62.5ppm, 25.0ppm and 5.0ppm respectively but the Manganese content of extract could not determined, Copper content of SA, SB and SC were 15.0ppm, 20.0ppm and those of extract were 7.5ppm, 6.5ppm, 4.5ppm while those of extraction ratio were 50%, 32.5% and 90% respectively, Zinc was abundant in Ginseng compared with other herbs, (SA: 45.5ppm, SB: 27.5ppm and SC: 5.5ppm) and the extracted amount were 4.5ppm, 1.25ppm 1.50ppm respectively.

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Dosimetric Comparison of One Arc & Two Arc VMAT Plan for Prostate cancer patients (Prostate Cancer 환자에 대한 One Arc와 Two Arc VMAT Plan의 선량 측정 비교 분석)

  • Kim, Byoung Chan;Kim, Jong Deok;Kim, Hyo Jung;Park, Ho Chun;Baek, Jeong Ok
    • The Journal of Korean Society for Radiation Therapy
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    • v.30 no.1_2
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    • pp.107-116
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    • 2018
  • Purpose : Intensity-modulated radiation therapy(IMRT) has been widely used for radiation therapy of Prostate Cancer because it can reduce radiation adverse effects on normal tissues and deliver more dose to the Prostate than 3D radiation therapy. Volumetric modulated arc therapy(VMAT) has been widely used due to recent advances in equipment and treatment techniques. VMAT can reduce treatment time by up to 55 % compared to IMRT, minimizing motion error during treatment. Materials and Methods : In this study, compared the MU and DVH values of 10 patients with prostate cancer by classifying them into 4 groups with 5 LN-Prostate groups and 5 Only-Prostate. And DQA measurements were performed using ArcCHECK and MapCHECK. Results : The results of Target and OAR dose distribution of Prostate patients are as follows. $D_{max}$ was in the range of 100~110 % in 4 groups, and more than 110 % of hot spot was not seen. Only-Prostate ($P_1$, $P_2$) without LN had a satisfactory dose distribution for the target dose, but slightly better for 2 arc plan($P_2$) than 1 arc plan($P_1$). The target dose $D_{98%}$ distribution in the LN-Prostate ($P_{L1}$, $P_{L2}$) group showed better 2 arc plan($P_{L2}$) than 1 arc plan($P_{L1}$), But in the case of 1 arc plan($P_{L1}$), the target dose $D_{98%}$ value was not enough. In OAR, the dose distribution of 1 Arc($P_1$) Plan and 2 Arc($P_2$) Plan in the Only-Prostate ($P_1$, $P_2$) Group satisfied the prescribed dose value. But, The dose distribution of 1 arc($P_1$) was slightly higher. In LN-Prostate OAR, 1 Arc($P_{L1}$) Plan showed higher dose than the prescribed dose. The Gamma evaluation pass rate of ArcCHECK and MapCHECK calculated from the DQA measurements was slightly higher than 99 % and the mean error range of the point dose measurements using the CC04 ion chamber was less than 1 %. Conclusion : In this study, Only-Prostate ($P_1$, $P_2$) group, the dose of 2 Arc plan was better. However, considering the treatment time and MU value, 1 Arc treatment method was more suitable. In the LN-Prostate ($P_{L1}$, $P_{L2}$) group, 2 Arc($P_{L2}$) treatment method showed better results and satisfied with Target $D_{98%}$ and OAR prescription dose.

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