• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.127-133
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• 2014

Purpose: Low dose of PET/CT is important because of Patient's X-ray exposure. The aim of this study was to evaluate the effectiveness of low-dose PET/ CT image through the CTAC and QAC of patient study and phantom study. Materials and Methods: We used the discovery 710 PET/CT (GE). We used the NEMA IEC body phantom for evaluating the PET data corrected by ultra-low dose CT attenuation correction method and NU2-94 phantom for uniformity. After injection of 70.78 MBq and 22.2 MBq of 18 F-FDG were done to each of phantom, PET/CT scans were obtained. PET data were reconstructed by using of CTAC of which dose was for the diagnosis CT and Q. AC of which was only for attenuation correction. Quantitative analysis was performed by use of horizontal profile and vertical profile. Reference data which were corrected by CTAC were compared to PET data which was corrected by the ultra-low dose. The relative error was assessed. Patients with over weighted and normal weight also underwent a PET/CT scans according to low dose protocol and standard dose protocol. Relative error and signal to noise ratio of SUV were analyzed. Results: In the results of phantom test, phantom PET data were corrected by CTAC and Q.AC and they were compared each other. The relative error of Q.AC profile was been calculated, and it was shown in graph. In patient studies, PET data for overweight patient and normal weight patient were reconstructed by CTAC and Q.AC under routine dose and ultra-low dose. When routine dose was used, the relative error was small. When high dose was used, the result of overweight patient was effectively corrected by Q.AC. Conclusion: In phantom study, CTAC method with 80 kVp and 10 mA was resulted in bead hardening artifact. PET data corrected by ultra- low dose CTAC was not quantified, but those by the same dose were quantified properly. In patients' cases, PET data of over weighted patient could be quantified by Q.AC method. Its relative difference was not significant. Q.AC method was proper attenuation correction method when ultra-low dose was used. As a result, it is expected that Q.AC is a good method in order to reduce patient's exposure dose.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.94-97
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• 2014

Purpose: Standardized uptake value (SUV) is a simple semi-quantitative method that can measure the ratio of the tissue radioactivity between the tumor and normal. SUV is commonly used in PET/CT, however, SUV is affected by various factor. The purpose of this study was to evaluate the impact of the residual activity on SUV depending on the location of catheter insertion device post injection. Materials and Methods: NEMA IEC Body Phantom was imaged using a Discovery 600 PET scanner. In 22 mm diameter sphere, the different activity of $^{18}F-FDG$ (7.4, 14.8, 22.2, 29.6, 37, 55.5 MBq) was filled and background was filled with $^{18}F-FDG$ (5.7 kBq/mL). We scaned the phantom on the assumption that the radioactivity in sphere was residual activity in insertion device. Simulation of PET was divided into three groups based on the location of sphere in Scan FOV (SFOV); inclusion, 1/2 inclusion and exclusion group. Results: Among three groups, the group of excluded sphere showed the highest SUV regardless of the amount of $^{18}F-FDG$ activity. In case of 7.4 MBq, average SUV of inclusion group, 1/2 inclusion and exclusion group was 0.780, 0.840 and 0.896 respectively. However, average SUV of 55.5 MBq showed 0.372, 0.460 and 0.508 with same order. Depend on residual radioactivity in the sphere and position of sphere, the SUV was different minimum of 10.4%, maximum of 62.8%. Conclusion: This study showed that SUV is underestimated as the residual radio-activity is increased. In addition, SUV was a changed according to the position of residual radio-activity. And among the position, exclusion group showed the difference of SUV was lowest. If we measure the residual radio-activity of inserting devices and radio-activity from extra-vasation in the patients, it seems to be more useful in clinical field.

• Korean Journal of Organic Agriculture
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• v.17 no.1
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• pp.95-109
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• 2009

This study was carried out to determine the effect of application seasons and rates with animal liquid slurry on the rice yield and quality. The treatments were application seasons (autumn, spring) and application rates of animal liquid slurry 80, 100, 120, 140% N levels of based on 11kg N/10a, chemical fertilizer as control plot. Field experiment was conducted at Cheorwon, Gangwon-Do in 2007. The results was as follows; The plant height and tiller's number at the application of spring season were higher than that at the autumn application. In the plot of 140% level at the spring application, the plant height and tillers were higher, and the color of leaf was darker than that of the chemical fertilizer. The plot of 140% level in spring application was increased the lodging damage of rice. Rice yield was reduced at 7%, 13% in the plot of 120%, 140 N/10a slurry level in the spring application compared to the chemical fertilizer, respectively. But rice yield at the autumn application was not significantly difference between chemical fertilizer and plots of liquid manure. The rice quality of the 120 and 140% slurry in spring application was significantly lower than that of chemical fertilizer. Total nitrogen contents and nitrogen uptake in rice plant were higher at the plot of 120, 140%N in the spring than that of chemical fertilizer. To reduce the lodging damage and increase the yield and quality of rice was needed suitable application of liquid manure In spring season.

• Journal of Wetlands Research
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• v.12 no.3
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• pp.1-13
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• 2010

Most of investigations about the effects of dam construction on the surrounding environments have focused mainly on the change of climate conditions and crop production. In order to research the effect of dam construction on the surrounding vegetation, we chose the Soyanggang dam whose storage capacity is the largest in Korea, and was built 33 years ago. We surveyed and analyzed the surrounding vegetation by using quadrat method and measured the soil moisture content among floodplain (FP), 5m above the flood plain (AFP) and control group (CG) which is 3km far from the lake through ridge. The largest value of mean importance percentage of the canopy~understory layer at FP was Salix koreensis (87.9%) and those of AFP and CG was Quercus mongolica (38.9% and 40.4% respectively) and the largest important percentage of the herb layer at FP was Artemisia capillaris (34.2%) and those of AFP and CG was Oplismenus undulatifolius var. undulatifolius (9.4% and 24.6% respectively). The Shannon-Wiener diversity index of shrub~canopy layer at FP (0.26) was lower than AFP (2.34) and CG (2.23) and there was not any significant difference in the herb layer among three groups. The S${\o}$rensen similarity index between FP and AFP, FP and CG was 0, and that of AFP and CG was relatively high. The highest density of tree and subtree with the DBH level of FP was S. koreensis of 5~10cm (240/ha), and that of AFP and CG was Quercus spp. of 15~20cm (400/ha and 466/ha respectively). And the highest density of seedlings of FP was Pinus densiflora (7,040/ha), and that of AFP and CG was Quercus spp. (720/ha and 400/ha respectively). The soil water content of FP (6.28%) was relatively lower than AFP and CG (11.13% and 10.14% respectively; p<.01). These results indicated that construction of Soyanggang dam changed the vegetation of the floodplain, without showing a change in its upland areas.

• Journal of Mushroom
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• v.17 no.4
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• pp.261-267
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• 2019

The objective of this study was to evaluate the antioxidant activity of extracts of Protaetia brevitarsis larvae fed on fermented oak sawdust (FOS) or spent mushroom substrates (SMS, Pleurotus eryngii). Total polyphenol content was 32% higher in extracts of larvae fed on SMS (P. eryngii) (75.33±0.43 mg GAE/g) than in extracts of larvae fed on FOS (57.02±1.73 mg GAE/g). The flavonoid content of extracts of larvae grown on FOS and SMS (P. eryngii) was 24.6±0.28 mg/g and 25.4±0.75 mg/g, respectively. DPPH radical scavenging activity increased in an extract concentration-dependent manner, and the DPPH radical scavenging capacity of the extract of larvae produced on SMS (P. eryngii) was higher than that of the larvae produced on FOS. The reducing power of the larval extracts produced on FOS and SMS (P. eryngii) increased in an extract concentration-dependent manner, but there was no significant difference between them. The extract of larvae fed on SMS (P. eryngii) (66.55±0.99 uM TE/g) had a higher oxygen radical absorbance capacity (ORAC) than extracts of larvae grown on FOS (76.32±0.48 uM TE/g). The effect of larval extracts on cell proliferation was investigated using a WST-1 (4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate) assay on RAW 264.7 cells. When cells were treated with larval extracts produced on FOS and SMS (P. eryngii) at concentrations of 0, 2, 4, 8, 16, 32, 40, and 64 mg/ml, RAW 264.7 cells proliferated at 90% or more. Therefore, larval extracts produced on FOS and SMS (P. eryngii) were not toxic to RAW 264.7 cells.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.4 no.1
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• pp.63-70
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• 2001

Purpose: The aim of this study is to evaluate the effective role of living-related liver transplantation (LRLT) on posttransplant linear growth in children. Methods: Thirty six children were enrolled who received LRLT at Asan Medical Center from December, 1994 to February, 1999 and showed more than one-year postoperative survival. Mean height standard deviation score (zH) was analyzed according to medical records including heights during pretransplant and posttransplant follow-up periods. Results: zH of total children showed significant linear growth after LRLT from -1.58 to 0.33 at 24 posttransplant month (p<0.05). zH in children under 6 years of age, to exclude the effect of adolescent linear growth spurt, showed increment in height (p<0.05). Linear growth of children with liver cirrhosis improved and that with fulminant hepatitis was matained same. While stunted children (mean zH=-2.30) achieved good catch-up growth after transplantation, children with normal growth remained same. Children with significant hepatic dysfunction after LRLT such as chronic rejection or posttransplant lymphoproliferative disorder showed retarded posttrasplant linear growth. There was no statistical difference according to the type of immunosuppressants. Conclusion: LRLT resulted in adequate or catch-up linear growth in children with acute, chronic and metabolic liver disease. Successful LRLT suggested to be a promising option not only in long term survival but also in normal linear growth.

• Journal of the Mineralogical Society of Korea
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• v.24 no.2
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• pp.73-82
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• 2011

X-ray absorption spectroscopy (XAS) study was conducted using arsenite-sorbed two-line ferrihydrite to investigate the mechanism of surface interactions between two-line ferrihydrite and As(III) (arsenite) which are ubiquitous in nature. The two-line ferrihydrite used was synthesized in the laboratory and the study was undertaken at pHs 4 and 10 to compare the difference in mechanisms of surface interaction between acidic and alkaline environments. The effect of arsenite-adsorbed concentrations on surface complexation was investigated at each pH condition as well. From the results of XAS analyses, the structural parameters of arsenite in the EXAFS revealed that the coordination number and distanceof As-O were 3.1~3.3 and 1.74~1.79 ${\AA}$, respectively, which indicate that the unit structure of arsenite complex formed on the surface of two-line ferrihydrite is $AsO_3$. The dominant structures of As(III)-Fe complex were examined to be bidentate binuclear comer-sharing ($^2C$) and the mixture of bidentate mononuclear edge sharing ($^2E$) and $^2C$ appeared as well. At pH 4, arsenite complex showed different structures on the surface of two-line ferrihydrite, depending on the adsorbed concentrations. At pH 10, on the contrary, the surface structures of arsenite complexes were interpreted to be almost identical, irrespective of the adsorbed concentrations of arsenite. Consequently, this microscopic XAS results support the results of macroscopic adsorption experiments in which the surface interaction between arsenite and two-line ferrihydrite is significantly influenced by pH conditions as well as arsenite concentrations.

• Magazine of the Korean Society of Agricultural Engineers
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• v.19 no.1
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• pp.4323-4337
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• 1977

The study was to estimate the effect of the rise of water temperature in the warm water pool and to make contribution to the establishment of reducing to a damage of cool water as well as to the planning for warm water pool. This observation was performed in Wudu warm water pool located at Wudu-Dong of Chuncheon for two years from 1975 to 1976. The results were showed as follows; 1. The daily variation of water temperature was the least for inset (No.1; 0.6$^{\circ}C$) the second for middle overflow (No2: 3$^{\circ}C$, No.3; 2.3$^{\circ}C$) and another for outflet (No.4; 3.6$^{\circ}C$, No.5; 3.8$^{\circ}C$) And the highest reaching time of water temperature in each block was later about 1 hour than the time at which air temperature happend in the daytime. So, the variation of water temperature was sensitive to the variation of air temperature 2. The monthly variation of water temperature at each measuring point was plotted to be increased with increase in air temperature till August (Mean monthly rising degree; No.1; 1.15$^{\circ}C$, No.2; 1.7$^{\circ}C$, No.3; 1.73$^{\circ}C$, No.4; 2.08$^{\circ}C$, No.5; 2.0$^{\circ}C$), and expressed gradually descended influence upon water temperature after August. 3. The mean temperature of inflow folwed in warm Water pool was 7.5∼12.5$^{\circ}C$, and outflow temperature was described as 13.4∼22.5$^{\circ}C$ to be climbed. And So, the rising interval of water temperature was shown as 6.7∼10.4$^{\circ}C$. 4. The correlation between the rising of water temperature and the weather condition was found out highly significant. As the result, their correlation coefficents of water temperature depending on mean air temperature, ground temperature, wind velocity and relative humidity were to be 0.93, 0.90, - 0.83 and 0.71 respectively. But there was no confrimation of the correlation on the clouds, sunlight time, volume of evaporation, and heat capacity of horizontal place. 5. The water temperature of balance during the period of rice growing in Chuncheon district was shown as table 10, and the mean of whole period was calculated as about 23.7$^{\circ}C$. 6. The observed value of the outflow temperature passed through the warm water pool was higher than that of computed, the mean difference between two value was marked as 1.15$^{\circ}C$ for blockl, 1.18$^{\circ}C$ for block2, and 0.47$^{\circ}C$ for block3, respectivly. Therefore, the ratio on the rising degree between the observed and computed were shown as 53%, 44%, and 18%, mean 38% through each block warm water pool (referring item $\circled9$ of table 11,12, and 13). Accordingly, formula (4) in order to fit for each block warm water pool was transfromed as follow; {{{{ { theta }_{w } - { theta }_{ 0} =[1-exp LEFT { { 1-(1+2 varphi )} over {cp } CDOT { A} over { q} RIGHT } ] TIMES ( { theta }_{w } - { theta }_{ 0}) TIMES C }}}} Here, correction coefficinent was computed 1.38, and being substituted 1.38 for C in preceding formula, the expected water temperature will be calculated to be able to irrigate the rice paddy. As the result, we can apply the coefficient in order to plan and to construct a new warm water pool.

• Korean Journal of Animal Reproduction
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• v.25 no.2
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• pp.163-169
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• 2001

OSBA(oocytes-sperm binding assay) is a tool developed for rapid test of optimal condition of IVF medium and protein source by binding ability of mouse sperm and egg. Mouse oocyte-cumulus complexes were prepared by removing of the cumulus cells with 0.1% hyaluronidase. 10$\pm$2 oocytes per 30 ${mu}ell$ medium drop were inseminated with 3 ${mu}ell$ sperm suspension and were cultured f3r 3 hours and 24 hours, respectively. And the oocytes were recovered gently and the No. of sperm bound on oocytes were counted. In the Exp. 1, the ratio of oocytes bound with one sperm at least were 60.2%(50/83), 2%(2/77) and 100%(79/79) in the medium with no protein, FBS(15%, v/v) and BSA(0.4%. w/v), respectively, Fetal bovine serum(FBS) seriously inhibited sperm binding on oocyte, although bovine serum albumin(BSA) promoted the binding ability. The inhibiting effect of FBS was dependent on the concentration of FBS. The sperm binding ability according to oocyte maturity was tested in the Exp. 2. There was no significant difference between Met. II (mature) and Met. I (intermediate mature) oocytes in the number of oocytes bound with sperm and the number of sperm bound on oocytes. Finally, in Exp. 3, two batches of Ham's F10 medium with good and poor quality by OSBA were tested (The ratios of embryos developed from PN 1-cell stage to hatched blastocyst; 25% vs. 70%). In the medium with good quality, sperm binding ability was significantly increased (P ＜ 0.05). The ratio of oocytes bound with one sperm at least was 66% and 90% in the medium with poor and good quality, respectively. Conclusively, It was possible to test IVF medium condition rapidly and easily by OSBA.

• Reproductive and Developmental Biology
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• v.31 no.3
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• pp.199-205
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• 2007

The present study was carried out to assess the effect of superovulation response and efficiency of embryo production induced with injection of FSH dissolved in polyethylene glycol (PEG) in Hanwoo. Eighty-eight cows were divided into four groups. In group 1, cattle were intramuscularly treated with twice-daily administration of 50mg FSH for 4 days. Group 2 and 3 were subcutaneously single injection of 400mg and 200mg FSH dissolved in 30% PEG, respectively. Group 4 were subcutaneously single injection of 200 mg FSH dissolved in 30% PEG at 7 day after CIDR insertion. The number of corpus luteum (CL) in group 2 resulted in significantly (p<0.05) higher compared to group 1, 3 and 4 (18.5 vs. 11.2, 13.1 and 13.9, respectively). However, the number of total ova $(7.9{\sim}10.4)$, transferable embryos $(3.7{\sim}4.7)$, degenerate embryos $(1.9{\sim}3.5)$ and unfertilized ova $(1.8{\sim}2.7)$ did not differ among treatment groups. No difference was observed in pregnancy rate after transferring the recovered embryos among groups $(36.0{\sim}50.0%)$. In addition, blood progesterone concentrations at embryo recovery did not differ among all groups. In conclusion, although no differences were observed in the number of total ova, transferable embryos and pregnancy rate after transfer, a single injection of reduced dose of FSH (200mg FSH) at 7 day after CIDR insertion is more practical for superovulation treatments than frequent injection because of reduction of stress in Hanwoo and decreases of cost and laber.