• Progress in Medical Physics
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• v.14 no.1
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• pp.15-19
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• 2003

High dose rate (HDR) brachytherapy for treating a cervix carcinoma has become popular, because it eliminates many of the problems associated with conventional brachytherapy. In order to improve the clinical effectiveness with HDR brachytherapy, a dose calculation algorithm, optimization procedures, and image registrations need to be verified by comparing the dose distributions from a planning computer and those from a phantom. In this study, the phantom was fabricated in order to verify the absolute doses and the relative dose distributions. The measured doses from the phantom were then compared with the treatment planning system for the dose verification. The phantom needs to be designed such that the dose distributions can be quantitatively evaluated by utilizing the dosimeters with a high spatial resolution. Therefore, the small size of the thermoluminescent dosimeter (TLD) chips with a dimension of <1/8"and film dosimetry with a spatial resolution of <1mm used to measure the radiation dosages in the phantom. The phantom called a pelvic phantom was made from water and the tissue-equivalent acrylic plates. In order to firmly hold the HDR applicators in the water phantom, the applicators were inserted into the grooves of the applicator holder. The dose distributions around the applicators, such as Point A and B, were measured by placing a series of TLD chips (TLD-to-TLD distance: 5mm) in the three TLD holders, and placing three verification films in the orthogonal planes. This study used a Nucletron Plato treatment planning system and a Microselectron Ir-192 source unit. The results showed good agreement between the treatment plan and measurement. The comparisons of the absolute dose showed agreement within $\pm$4.0 % of the dose at point A and B, and the bladder and rectum point. In addition, the relative dose distributions by film dosimetry and those calculated by the planning computer show good agreement. This pelvic phantom could be a useful to verify the dose calculation algorithm and the accuracy of the image localization algorithm in the high dose rate (HDR) planning computer. The dose verification with film dosimetry and TLD as quality assurance (QA) tools are currently being undertaken in the Catholic University, Seoul, Korea.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.1
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• pp.28-32
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• 2006

Purpose: Conventional chest X-ray and pulmonary function test cannot sensitively detect inhalation injury. Bronchoscopy is known to be the gold standard but it is invasive method. We evaluated whether lung inhalation/perfusion scans can sensitively detect inhalation injury of fire victims. Materials and Methods: Nineteen patients (male 9, female 10, mean age 31.6 yr) of fire victims were enrolled in this study. Inhalation lung scan was performed 2 days later after inhalation injury with $^{99m}Tc$-technegas. Perfusion lung scan was performed 4 days later with $^{99m}Tc$- MAA (macroaggregated albumin). Follow up lung scans were performed 16 and 18 days later for each. Chest X-ray was performed in all patients and bronchoscopy was performed in 17 of 19 patients at the same period. Pulmonary function test was performed in 9 patients. Results: Four of 19 patients showed inhalation and perfusion defects and one showed inhalation defect but, normal perfusion scan findings. These five patients with abnormal scan findings showed abnormal bronchoscopic findings and severe respiratory symptoms. On chest X-ray, 2 of them had pulmonary tuberculosis and one of them showed pulmonary congestion. FEV1 /FVC was abnormal in 3 patients. On the follow up scan, all patients with abnormal initial scan findings showed improved findings and they had improved clinical state. Conclusion: Inhalation/perfusion lung scans can detect inhalation burn injury noninvasively in early stage and may be useful in therapeutic decision making and follow up of patients.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.1
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• pp.33-39
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• 2006

Purpose: To determine appropriate sampling frequency and time of multiple blood sampling dual exponential method with $^{99m}Tc$-DTPA for calculating glomerular filtration rate (GFR). Materials & Methods: Thirty four patients were included in this study. Three mCi of $^{99m}Tc$-DTPA was intravenously injected and blood sampling at 9 different times, 5ml each, were done. Using the radioactivity of serum, measured by gamma counter, the GFR was calculated using dual exponential method and corrected with the body surface area. Using spontaneously chosen 2 data points of serum radioactivity, 15 collections of 2-sample GFR were calculated. And 10 collections of 3-sample GFR and 12 collections of 4-sample GFR were also calculated. Using the 9-sample GFR as a reference value, degree of agreement was analyzed with Kendall's $\tau$ correlation coefficients, mean difference and standard deviation. Results: Although some of the 2-sample GFR showed high correlation coefficient, over or underestimation had evolved as the renal function change. The 10-120-240 min 3-sample GFR showed a high correlation coefficient (${\tau}=0.93$), minimal difference ($Mean{\pm}SD=-1.784{\pm}3.972$), and no over or underestimation as the renal function changed. The 4-sample GFR showed no better accuracy than the 3-sample GFR. Conclusions: In the wide spectrum of renal function, the 10-120-240 min 3-sample GFC could be the best choice for estimating the patients' renal function.

• The Korean Journal of Nuclear Medicine
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• v.35 no.1
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• pp.23-32
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• 2001

Purpose: Cortical dysplasia (CD) designates a diverse group of malformations resulting from one or more abnormalities in the development of the cerebral cortex. We investigated the findings of interictal SPECT and the diagnostic usefulness of interical and ictal SFECT according to pathological grading (PG) in comparison with MRI. Materials and Methods: This study included 16 patients (M:F=9:7, age: $19.9{\pm}11.8$ yrs) with pathologically proven CD. Tc-99m ECD SPECT was performed in all patients: interictal 11, interictal and ictal 3, ictal 2. MRI were obtained in all patients and image analysis was done blindly as to the result of SPECT. Pathologic findings of CD were classified into grade 1 G1, dyslamination), grade 2 (G2, dysplastic neurons) and grade 3 (G3, balloon cells). We compared SFECT with MRI in lesions-to-lesions and analyzed the result according to PG. Results: In SFECT and MRI. 38 and 27 lesions were visually recognized. In 14 interictal SPECT, variable findings in 35 lesions were demonstrated: 25 were hypoperfusion, 7 hyperperfusion, 2 heterotopic perfusion in the white matter. By comparison between two studios, missed lesions were founded: SPECT were 1 lesion, MRI 12. Review of missed 12 lesions of MRI were followed according to PG: G1 patients were 16.7% (4/19), G2 40.0% (6/15), and G3 50% (2/4). Conclusion: Interictal SFECT in CD showed variable findings such as hypoperfusion, hyperperfusion or heterotopic perfusion. However, for detection of missed CD on MRI, SFECT may help to detect a functional abnormality of the lesion with high PG.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.3
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• pp.201-208
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• 2007

Purpose: We investigated whether the diagnostic performance of SPECT scintimammography (SMM) can be improved by adding computer-aided diagnosis (CAD) of ultrasonography (US). Materials and methods: We reviewed breast SPECT SMM images and corresponding US images from 40 patients with breast masses (21 malignant and 19 benign tumors). The quantitative data of SPECT SMM were obtained as the uptake ratio of lesion to contralateral normal breast. The morphologic features of the breast lesions on US were extracted and quantitated using the automated CAD software program. The diagnostic performance of SPECT SMM and CAD of US alone was determined using receiver operating characteristic (ROC) curve analysis. The best discriminating parameter (D-value) combining SPECT SMM and the CAD of US was created. The sensitivity, specificity and accuracy of combined two diagnostic modalities were compared to those of a single one. Results: Both SPECT SMM and CAD of US showed a relatively good diagnostic performance (area under curve = 0.846 and 0.831, respectively). Combining the results of SPECT SMM and CAD of US resulted in improved diagnostic performance (area under curve =0.860), but there was no statistical differerence in sensitivity, specificity and accuracy between the combined method and a single modality. Conclusion: It seems that combining the results of SPECT SMM and CAD of breast US do not significantly improve the diagnostic performance for diagnosis of breast cancer, compared with that of SPECT SMM alone. However, SPECT SMM and CAD of US may complement each other in differential diagnosis of breast cancer.

• Journal of Life Science
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• v.26 no.11
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• pp.1237-1244
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• 2016

A comprehensive analysis of the genetic diversity and relationship of the cold-water fishery walleye pollock (Theragra chalcogramma), the most abundant economically important fishery resource in the East sea of Korea, has not been carried out, despite its importance in Korea. The present study assessed the genetic diversity and relationship between five walleye pollock populations (Korean population, Russian population, USA population, and Japanese populations) of T. chalcogramma using eight microsatellite DNA (msDNA) markers to provide the scientific data for the preservation and management of the Pollock fishery resource. The results of the analysis of 186 individuals of the Pollock revealed a range of 7.13-10.63 numbers of alleles (mean number of alleles=9.05). The means of observed heterozygosity ($H_O$), expected heterozygosity ($H_E$) were 0.732 and 0.698, respectively. The results of genetic distance, Pairwise $F_{ST}$, UPGMA (UPGMA: un-weighted pair-group method with an arithmetical average) (the phylogenetic tree), PCA (PCA: Principal Coordinate analysis) analysis pointed to significant differences between the Korean population, Russian population, USA population, and Japanese populations, although small (p<0.05). These results shed light on the genetic diversity and relationships of T. chalcogramma and can be utilized for research on the evaluation and conservation of Korean T. chalcogramma as genetic resources.

• Journal of Broadcast Engineering
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• v.19 no.6
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• pp.877-895
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• 2014

It is common sense that providing specific odor can increase the video reality when video scene has an object having specific odor. However, people still do not know how to increase video reality and emotional immersion when there is no information on specific odor in the scene. So, present study explores how we improve video reality and immersion when the scene has no concrete odor information from some objects. Especially, this research focuses on diverse previous studies about matching between odor and color and then we expect providing odor can increase video reality if the odor is well-matched with the video's color. To do this, we collected 48 odors and investigated which color was well-matched with each odor. As a result, we get 5 odors which had clearly well-matched colors and decide ill-matched colors of those 5 odors as complementary colors of well-matched colors (Experiment 1). After that, we organize 3 conditions such as coloring image and video clip with well-matched color (color-odor match condition), coloring those with ill-matched color (color-odor mismatch condition), and coloring those with achromatic color by removing color saturation (color-odor neutral condition). Under each of these three conditions, image-odor matching, increment of reality with the odor, increment of immersion with the odor, and odor preference are asked (Experiment 2; 3). The results showed that the scores of all 4 questions in color-odor match condition were higher than color-odor mismatch condition and neutral condition. These results mean that providing matching odor with the scene's color in video is very effective to increase video reality and immersion. We expect experiencing better reality and immersion with olfactory information by adding various future research.

• Korean Journal of Food Science and Technology
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• v.38 no.6
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• pp.823-828
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• 2006

We established the optimal conditions for the hot water extraction of Camellia japonica compounds based on the yield, the stability (observed by peak changes on an HPLC chromatogram), and the 1,1-diphenyl-1-picrylhydrazyl radical-scavenging activity of the extracts. The extracts were prepared at $90^{\circ}C$ using six solution volumes (ranging from 100 mL to 600 mL), and four different extraction times (10, 30, 60, and 120 min). The results showed that increasing of the extraction volume elevated the radical-scavenging activity of the extracts; however, changes in volume had minimal affects on their yields and their stabilities. An increase in extraction time improved the compound yield; however, it reduced their stability and increased the deterioration of their radical-scavenging activity. Based on our results, we propose the following conditions to be optimal for the hot water extraction of dried C. japonica leaves: a water volume (mL) that is 60 times the weight (g) of the sample at a temperature of $90^{\circ}C$ for 30 min.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.1
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• pp.43-48
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• 2010

This study was conducted to compare the chemical composition, dry matter digestibility (DMD), dry matter intake, and utilization of nitrogen and energy of dairy goats (Saanen), when fed on imported timothy hay (IT), mixture grass hay (MG) and native grass hay (NG), respectively. The experimental trials were conducted from April, 2008 to December, 2008 at the environmental controlled barn of Chungnam National University. Twelve dairy goats (Saanen) were selected which had nearly the same body weight (24.2kg, male). The content of crude protein (CP) of MG hay was higher than that of other diets (p<0.05), but the contents of NDF, ADF, cellulose and lignin of IT and NG diet were higher than those of MG diet (p<0.05). The voluntary DM intake of dairy goats fed with herbage from MG diet (30.7/$BW_{kg}$/day) was higher than that of other diets, but no significant difference was observed between that of IT diet and NG diet (p>0.05). The DMD of MG diet (69.8%) was higher than that of NG diet (62.2%) and IT diet (60.8%) (p<0.05), but no significant difference was observed between that of IT diet and NG diet (p>0.05). In nitrogen utilization, the apparently digested N %, retained % and biological value of dairy goats fed with herbage from MG diet were higher and TG diet was lower (p<0.05). In energy utilization, digestible energy and the energy of apparently digested minus urinary losses of MG diet were higher than those of IT diet and NG diet (p<0.05), but no significant difference was found between IT diet and NG diet (p>0.05). Based on the results, the dry matter intake, DMD and utilization of nitrogen and energy of dairy goats of MG were higher than those of IT diet and NG diet (p<0.05), the DMD and biological value (%) of NG diet was higher than that of IT diet (p<0.05).

• Korean Journal of Biological Psychiatry
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• v.3 no.2
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• pp.277-287
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• 1996

Objective : It has been proposed that cognition and related aspects of mental functioning are decreased in depression as well as in alcoholism. The objective of the study was to compare behavioral side effects of paroxetine and amitriptyline in depressed patients accompanied by alcoholism. The focused comparisons were drug effects concerning psychomotor performance, cognitive function, sleep and daytime sleepiness during the first 2 weeks of treatment. Methods : After an alcohol detoxification period(3 weeks) and a washout period(1 week), a total of 20 male inpatients with alcohol use disorder (DSM-IV), who also had a major depressive episode(DSM-IV), were treated double-blind with paroxetine 20mg/day(n=10) or amitriptyline 25mg/day(n=10) for 2 weeks. All patients were required to have a scare of at least 18 respectively on bath the Hamilton Rating Scale far Depression(HAM-D) and Beck Depression Inventory(BDI) at pre-drug baseline. Patients randomized to paroxetine received active medication in the morning and placebo in the evening whereas those randomized to amitriptyline received active medication in the evening and placebo in the morning. All patients performed the various tasks in a test battery at baseline and at days 3, 7 and 14. The test battery included : critical flicker fusion threshold for sensory information processing capacity : choice reaction time for gross psychomotor performance : tracking accuracy and latency of response to peripheral stimulus as a measure of line sensorimotor co-ordination and divided attention : digit symbol substitution as a measure of sustained attention and concentration. To rate perceived sleep and daytime sleepiness, 10cm line Visual analogue scales were employed at baseline and at days 3, 7 and 14. The subjective rating scales were adapted far this study from Leeds sleep Evaluation Questionnaire and Epworth Sleepiness Scale. In addition a comprehensive side effect assessment, using the UKU side effect rating scale, was carried out at baseline and at days 7 and 14. The efficacy of treatment was evaluated using HAM-D, BDI and clinical global impression far severity and improvement at days 7 and 14. Results : The pattern of results indicated thai paroxetine improved performance an mast of the lest variables and also improved sleep with no effect on daytime sleepiness aver the study period. In contrast, amitriptyline produced disruption of performance on same tests and improved sleep with increased daytime sleepiness in particular at day 3. On the UKU side effect rating scale, mare side effects were registered an amitriptyline. The therapeutic efficacy was observed in favor of paroxetine early in day 7. Conclusion : These results demonstrated thai paroxetine in much better than amitriptyline for the treatment of depressed patients accompained by alcoholism at least in terms of behavioral safety and tolerability, furthermore the results may assist in explaining the therapeutic outcome of paroxetine. For example, and earlier onset of antidepressant action of paroxetine may be caused by early improved cognitive function or by contributing to good compliance with treatment.