• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.104-109
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• 2010

Purpose: $[^{18}F]$Fallypride plays an effective radiotracer for the study of dopamine $D_2/D_3$ receptor occupancy, neuropsychiatric disorders and aging in humans. This tracer has the potential for clinical use, but automated labeling efficiency showed low radiochemical yields about 5~20% with relatively long labelling time of fluorine-18. In present study, we describe an improved automatic synthesis of [$^{18}F$]Fallypride using different base concentration for routine clinical use. Materials and Methods: Fully automated synthetic process of [$^{18}F$]Fallypride was perform using the TracerLab $FX_{FN}$ synthesizer under various labeling conditions and tosyl-fallypride was used as a precursor. [$^{18}F$]Fluoride was extracted with various concentration of $K_{2.2.2.}/K_2CO_3$ from $^{18}O$-enriched water trapped on the ion exchange cartridge. After azeotropic drying, the labeling reaction proceeded in $CH_3CN$ at $100^{\circ}C$ for 10 or 30 min. The reaction mixture was purified by reverse phase HPLC and collected organic solution was exchanged by tc-18 Sep-Pak for the clinically available solution. Results: The optimal labeling condition of [$^{18}F$]Fallypride in the automatic production was that 2 mg of tosyl-fallypride in acetonitrile (1 mL) was incubated at $100^{\circ}C$ for 10 min with $K_{2.2.2.}/K_2CO_3$ (11/0.8 mg). [$^{18}F$]Fallypride was obtained with high radiochemical yield about $66{\pm}1.4%$ (decay-corrected, n=28) within $51{\pm}1.2$ min including HPLC purification and solid-phase purification for the final formulation. Conclusion: [$^{18}F$]Fallypride was prepared with a significantly improved radiochemical yield with high specific activity and shorten synthetic time. In addition, this automated procedure provides the high reproducibility with no synthesis failures (n=28).

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.6 s.336
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• pp.67-74
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• 2005

In this paper, high LO-RF isolation W-band MIMIC single-balanced mixer was designed and fabricated using a branch line coupler and a $\lambda$/4 transmission line. The simulation results of the designed 94 GHz balun show return loss of -27.9 dB, coupling of -4.26 dB, and thru of -3.77 dB at 94 GHz, respectively. The isolation and phase difference were 23.5 dB and $180.2^{\circ}$ at 94 GHz. The W-band MIMIC single-balanced mixer was designed using the 0.1 $\mu$m InGaAs/InAlAs/GaAs Metamorphic HEMT diode. The fabricated MHEMT was obtained the cut-off frequency(fT) of 189 GHz and the maximum oscillation frequency(fmax) of 334 GHz. The designed MIMIC single-balanced mixer was fabricated using 0.1 $\mu$m MHEMT MIMIC Process. From the measurement, the conversion loss of the single-balanced mixer was 23.1 dB at an LO power of 10 dBm. Pl dB(1 dB compression point) of input and output were 10 dBm and -13.9 dBm respectively. The LO-RF isolations of single-balanced mixer was obtained 45.5 dB at 94.19 GHz. We obtained in this study a higher LO-RF isolation compared to some other balanced mixers in millimeter-wave frequencies.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.683-690
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• 2000

In this research high-fat-diet, which amounts to 40% out of the total calories, is prepared and taken to SD-lined rats for four weeks, and the exercise is taken using treadmill so that two groups are formed; one is for exercise group (E, EG) and the other for non-exercise group (CO,G). In addition the diet-intake-amount and body weight are measured for momparing a green tea extract intake group (EG,G) with a non-intake group (CO,E) and then serum lipid components can be analyzed after four weeks. Considering the total diet amounts for four weeks, Co group has the largest while the EG group does the smallest for the diet-intake-amounts; there is, however, no significant difference among all groups. Both body weight gain and the feed efficiency ratio of the CO group are larger than those of the EG and G group with significant differences (p<0.05). Taking into account the serum lipid components analysis, all of serum total cholesterol, LDL-cholesterol, and triglyceride of EG group have smaller values than those of non-exercise groups (CO,G) with significant differences (p<0.05) respectively, while HDL/LDL-cholesterol of EG group does a larger value than that of non-exercise groups with significant difference (p<0.05); these, hence, show efficient results. For the HDL-cholesterol level, there are no significant differences among each group and the ratio TC/HDL-cholesterol of EG group is smaller than that of Co group with a significant difference (p<0.05). Therefore, we can draw conclusions that exercise and green tea extract intake group (EG) has relatively better results than non-exercise groups (CO, G) through serum lipid components results and furthermore the effects of the green tea extracts intake is considered to play a supplementary role for the improvement of the serum lipid components.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.1
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• pp.1-16
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• 2007

The use of information on natural resources is indispensable to most agricultural activities to avoid disasters, to improve input efficiency, and to increase lam income. Most information is prepared and managed at a spatial scale called the "Hydrologic Unit" (HU), which means watershed or small river basin, because virtually every environmental problem can be handled best within a single HU. South Korea consists of 840 such watersheds and, while other watershed-specific information is routinely managed by government organizations, there are none responsible for agricultural weather and climate. A joint research team of Kyung Hee University and the Agriculture, forestry and Fisheries Information Service has begun a 4-year project funded by the Ministry of Agriculture and forestry to establish a watershed-specific agricultural weather information service based on "high definition" digital climate maps (HD-DCMs) utilizing the state of the art geospatial climatological technology. For example, a daily minimum temperature model simulating the thermodynamic nature of cold air with the aid of raster GIS and microwave temperature profiling will quantify effects of cold air drainage on local temperature. By using these techniques and 30-year (1971-2000) synoptic observations, gridded climate data including temperature, solar irradiance, and precipitation will be prepared for each watershed at a 30m spacing. Together with the climatological normals, there will be 3-hourly near-real time meterological mapping using the Korea Meteorological Administration's digital forecasting products which are prepared at a 5 km by 5 km resolution. Resulting HD-DCM database and operational technology will be transferred to local governments, and they will be responsible for routine operations and applications in their region. This paper describes the project in detail and demonstrates some of the interim results.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.849-858
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• 2007

This study was intended to collect the baseline information on health status, nutrient intakes and dietary self-efficacy according to the obesity levels of male workers. Nutrient intakes of 224 male workers were assessed by 24 hr recall method; also, dietary attitude and dietary self-efficacy were investigated by self-administerd questionnaires. Biochemical characteristics such as blood pressure (SBP, DBP), total cholesterol(TC), hemoglobin (Hb), blood glucose (BG), SGOT, SGPT and ${\gamma}-GTP$ were assessed. Subjects were divided into normal, overweight and obese groups by body mass index (BMI). The health status was analyzed as normal group, health concerned group and disease suspected group. Weight, percent ideal body weight (PIBW), BMI and body circumference (waist, hip) and waist-hip ratio were high in the order of obese group, overweight group and normal group. Body fat mass was high also in the order of obese, overweight and normal group. Blood pressure (SBP, DBP) was the highest in obese group. SGOT, SGPT, ${\gamma}-GTP$ were higher in the obese group than normal and overweight groups. It was Proven that the percentage of those evaluated as low nutrient intakes were 71% for Ca, 50.9% for Zn, 70.5% for vitamin B2, 56.3% for vitamin C and 81.3% for folic acid. The dietary attitude scores were high according to the dietary self-efficacy. The age was positively correlated with dietary attitude, and the dietary attitude was positively correlated with dietary self-efficacy and total energy intakes. Dietary attitude showed the greatest total causal effect in relation to dietary self-efficacy. The results of this study showed some health problems and nutritional problems, indicating the need for nutritional management for male workers.

• 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.

• Korean Journal of Food Science and Technology
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• v.54 no.3
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• pp.297-305
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• 2022

The goal of this study was to evaluate the anti-obesity effect of radish leaf extracts (MU-C) and radish leaf extracts with 3% citric acid (MU-CA) in a high-fat diet (HFD)-induced C57BL/6 mice. The effects of radish leaf extracts on adipogenesis were also investigated using 3T3-L1 adipocytes. As determined by Oil red O staining, MU-C inhibited adipogenesis in 3T3-L1 adipocytes. Four-week-old male C57BL/6 mice were fed an HFD for 6 weeks and then treated with radish leaf extracts (500 mg/kg, p.o.) for 6 weeks. Then, the serum levels of Aspartate aminotransferase, Alanine aminotransferase, Total cholesterol, Triglyceride and low-density lipoprotein cholesterol in the mice were measured using an automatic chemical analyzer and enzyme-linked immunosorbent assay. Administration of MU-C significantly reduced the fat weight when compared with HFD controls. As confirmed by histopathologic analysis, adipose tissue size markedly decreased in mice treated with MU-C. Therefore, this study could provide a basis for investigating the clinical use of MU-C as an agent for preventing obesity.

• Journal of radiological science and technology
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• v.38 no.1
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• pp.23-30
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• 2015

Positron emission tomography scan has been growing diagnostic equipment in the development of medical imaging system. Compare to 99mTc emitting 140 keV, Positron emission radionuclide emits 511 keV gamma rays. Because of this high energy, it needs to reduce radioactive emitting from patients for radio technologist. We searched the external dose rates by changing distance from patients and measure the external dose rates when we used shielder investigate change external dose rates. In this study, the external dose distribution were analyzed in order to help managing radiation protection of radio technologists. Ten patients were searched (mean age: $47.7{\pm}6.6$, mean height: $165.5{\pm}3.8cm$, mean weight: $65.9{\pm}1.4kg$). Radiation was measured on the location of head, chest, abdomen, knees and toes at the distance of 10, 50, 100, 150, and 200 cm, respectively. Then, all the procedure was given with a portable radiation shielding on the location of head, chest, and abdomen at the distance of 100, 150, and 200 cm and transmittance was calculated. In 10 cm, head ($105.40{\mu}Sv/h$) was the highest and foot($15.85{\mu}Sv/h$) was the lowest. In 200 cm, head, chest, and abdomen showed similar. On head, the measured dose rates were $9.56{\mu}Sv/h$, $5.23{\mu}Sv/h$, and $3.40{\mu}Sv/h$ in 100, 150, and 200 cm, respectively. When using shielder, it shows $2.24{\mu}Sv/h$, $1.67{\mu}Sv/h$, and $1.27{\mu}Sv/h$ in 100, 150, and 200 cm on head. On chest, the measured dose rates were $8.54{\mu}Sv/h$, $4.90{\mu}Sv/h$, $3.44{\mu}Sv/h$ in 100, 150, and 200 cm, respectively. When using shielder, it shows $2.27{\mu}Sv/h$, $1.34{\mu}Sv/h$, and $1.13{\mu}Sv/h$ in 100, 150, and 200 cm on chest. On abdomen, the measured dose rates were $9.83{\mu}Sv/h$, $5.15{\mu}Sv/h$, and $3.18{\mu}Sv/h$ in 100, 150, and 200 cm, respectively. When using shielder, it shows $2.60{\mu}Sv/h$, $1.75{\mu}Sv/h$, and $1.23{\mu}Sv/h$ in 100, 150, and 200 cm on abdomen. Transmittance was increased as the distance was expanded. As the distance was further, the radiation dose were reduced. When using shielder, the dose were reduced as one-forth of without shielder. The Radio technologists are exposed of radioactivity and there were limitations on reducing the distance with Therefore, the proper shielding will be able to decrease radiation dose to the technologists.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.33-37
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• 2010

Purpose: In the early stage of using PET/CT, it was used to damper revision but recently shows that CT with MDCT is commonly used and works well for an anatomical diagnosis. This hospital makes the accuracy and convenience more higher in the diagnosis and evaluate of coronary heart disease through concurrently running myocardial perfusion SPECT examination, myocardial PET examination with FDG, and CT coronary artery CT angiography(coronary CTA) used PET/CT with 64-slice. This report shows protocol and image based on results from about 400 coronary heart disease examinations since having 64 channels PET/CT in July 2007. Materials and Methods: An Equipment for this examination is 64-slice CT and Discovery VCT (DVCT) that is consisted of PET with BGO ($Bi_4Ge_3O_{12}$) scintillation crystal by GE health care. First myocardial perfusion SPECT with pharmacologic stress test to reduce waiting time of a patient and get a quick diagnosis and evaluation, and right after it, myocardial FDG PET examination and coronary CTA run without a break. One-stop evaluation protocol of ischemic heart disease is as follows. 1)Myocardial perfusion SPECT with pharmacologic stress: A patient is injected with $^{99m}Tc$-MIBI 10 mCi and does not have any fatty food for myocardial PET examination and drink natural water with ursodeoxcholic acid 100 mg and we get SPECT image in an hour. 2)Myocardial FDG PET: To reduce blood fatty content and to increase uptake of FDG, we used creative oral glucose load using insulin and Acipimox to according to blood acid content. A patient is injected with $^{18}F$-FDG 5 mCi for reduction of his radiation exposure and we get a gated image an hour later and get delay image when we need. 3) Coronary CTA: The most important point is to control heart rate and to get cooperation of patient's breath. In order to reduce a heart rate of him or her below 65 beats, let him or her take beta blocker 50 mg ~ 200 mg after a consultation with a doctor about it and have breath-practices then have the examination. Right before the examination, we spray isosorbide dinitrate 3 to 5 times to lower tension of bessel wall and to extension a blood wall of a patient. It makes to get better the shape of an anatomy. At filming, a patient is injected CT contrast with high pressure and have enough practices before the examination in order to have no problem. For reduction of his radiation exposure, we have to do ECG-triggered X-ray tube modulation exposure. Results: We evaluate coronary artery stenosis through coronary CTA and study correlation (culprit vessel check) of a decline between stenosis and perfusion from the myocardial perfusion SPECT with pharmacologic stress, coronary CTA, and can check viability of infarction or hibernating myocardium by FDG PET. Conclusion: The examination makes us to set up a direction of remedy (drug treatment, PCI, CABG) because we can estimate of effect from remedy, lesion site and severity. In addition, we have an advantage that it takes just 3 hours and one-stop in that all of process of examinations run in succession and at the same time. Therefore it shows that the method is useful in one stop evaluation of ischemic heart disease.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.2
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• pp.31-36
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• 2013

Purpose: Measure gastric emptying time (GET: Gastric Emptying Time) is a non-invasive and quantitative evaluation methods, mainly by endoscopic or radiological examination confirmed no mechanical obstruction in patients with symptoms of congestion is checked. Such tests are not common gastric emptying time measured esophageal cancer patients (who underwent esophagectomy) patients after surgery for gastric emptying time was measured test. And the period of time for more than one year after the gastric emptying time measurement was performed. By comparing the two kinds of tests in the chest cavity after surgery as the evaluation of gastrointestinal function tests evaluate the usefulness of GET, and will evaluate the characteristics of the image. Materials and Methods: 93 patients who underwent esophagectomy with gastric emptying time measurement of subject tests immediately after surgery and after 1 year or longer were twice. Preparation of the patient before the test is more than 12 hours of overnight fasting is important, in addition to the medicine or to stop smoking, and diabetes insulin injections should be early in the morning is ideal to test. Generally labeled with $^{99m}Tc-DTPA$ resin which is used to make steamed egg, seaweed and fermented milk with a high viscosity after eating, three hours in the standing position was measured. Evaluation of gastric emptying curves on the way intragastric radioactivity level by 50% the time (half-time [T1/2]) was calculated, based on the half-life was divided into three steps: over 180 minutes was defined as delayed gastric emptying, within 180minutes was defined as intermediate gastric emptying and when all the radioisotopes were dumped into the jejunum as soon as swallowed, was defined as rapid gastric emptying. Results: Gastric emptying time of a typical images stomach of antrum and fundus additional images appear stronger over time move on to the small intestine. but esophageal cancer who underwent esophagectomy side of the thoracic cavity showed a strong image. Immediately after surgery, the half-time (T1/2) of rapid gastric emptying appeared to 12.9%, intermediate gastric emptying appeared to 52.7%, delay gastric emptying appeared to 34.4%. After more than a year the results of the half-life after surgery, 67% of rapid gastric emptying to intermediate gastric emptying was changed, 69% of delay gastric emptying to intermediate gastric emptying changed. Intermediate gastric emptying worse in patients rapid gastric emptying and the delay gastric emptying is 24% in the case. Conclusion: Esophagectomy for esophageal cancer who underwent half-time measurement test (T1/2) rapid gastric emptying and delay gastric emptying are the result of the comparison over time, changes were observed intermediate gastric emptying. Mainly seeing of gastric emptying time measurement in the esophagus instead of thoracic cavity to check the evaluation of gastrointestinal function can be useful even means. And segmentation criteria and narrow time interval of checking if more accurate information and analysis of the clinical diagnosis and evaluation seems to be done.