• The Korean Journal of Nuclear Medicine
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• v.35 no.3
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• pp.142-151
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• 2001

Purpose: This study was performed to search the relatively specific brain regions related to the semantic processing of Korean and English words on the one hand and the regions common to both on the other. Materials and Methods: Regional cerebral blood flow associated with different semantic tasks was examined using $[^{15}O]H_2O$ positron omission tomography in 13 healthy volunteers. The tasks consisted of semantic tasks for Korean words, semantic tasks for English words and control tasks using simple pictures. The regions specific and common to each language were identified by the relevant subtraction analysis using statistical parametric mapping. Results: Common to the semantic processing of both words, the activation site was observed in the fusiform gyrus, particularly the left side. In addition, activation of the left inferior temporal gyrus was found only in the semantic processing of English words. The regions specific to Korean words were observed in multiple areas, including the right primary auditory cortex; whereas the regions specific to English words were limited to the right posterior visual area. Conclusion: Internal phonological process is engaged in performing the visual semantic task for Korean words of the high proficiency, whereas visual scanning plays an important role in performing the task for English words of the low proficiency.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1266-1266
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• 2001

Pasture composition, an important attribute determining sward condition and value, is normally assessed by hand separation, drying and measuring weight contribution of each species in the mixture. This is a tedious, time and labour consuming procedure. NIRS has demonstrated the potential for predicting botanical composition of swards, but most of the work has been carried out on dry samples. The aim of this work was to evaluate the feasibility of developing NIR models for predicting the white clover and ryegrass content in fresh or dry mixtures artificially prepared from pure samples of both species. Mixtures from pure stands of white clover(Trifolium repens) and perennial ryegrass (Lolium perenne) were prepared with different proportions (0 to 100%) of each species (fresh weight). A total of 55 samples were made (11 mixtures,5 cuts). Spectra (400 to 2500 nm) were taken from fresh chopped (rectangular cuvettes, transport sample module) samples, in a NIR Systems 6500 scanning monochromator controlled by the software NIRS 3 (Infrasoft International), which was also utilized for calibration development. Different math treatments (derivative order, subtraction gap and smooth segment) and a scatter correction treatment of the spectra (SNV and Detrend) were tested. Equations were developed by modified partial least squares. Prediction accuracy evaluated by cross-validation, showed that percentage of clover or ryegrass, as contribution in dry weight, can be successfully percentage of clover or ryegrass, as contribution in dry weight, can be successfully predicted either on fresh or dried samples, with equations developed by different math treatments. Best equations for fresh samples were developed including a first, second, or third derivative, whereas for dry samples best equations included a second or third derivative. Standard errors of ross validation were about 6% for fresh and 3.6% for dry samples, Coefficient of determination of cross validation (1-VR) were over 0.95 times the value of SECV for fresh samples and over 8 times the value of SECV for dry samples. Scatter correction (SNV and Detrend) in general improved prediction accuracy. It is concluded more precise on dried and ground samples, it can be used with an acceptable error level and less time and labour, on fresh samples.

• Progress in Medical Physics
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• v.21 no.3
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• pp.274-280
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• 2010

The purpose of this study was to analyze the effect of single-fraction stereotactic radiosurgery (SRS) for the treatment of 15 cases of cerebral arteriovenous malformations (AVMs). Between 2002 and 2009, of the 25 patients who had SRS for the treatment of cerebral AVM, 15 patients (6 men, 9 women) taken a digital subtraction angiography (DSA) over 12 months after SRS were included. We retrospectively evaluated the size, location, hemorrhage of nidus, angiographic changes on follow-up on the MR angiography and DSA, and clinical complications during follow-up periods. At a median follow-up of 24 months (range 12-89), complete obliteration of nidus was observed in all patients (100%) while residual draining veins was observed in 3 patients (20%). There was no clinical complication during the follow-up period except seizure in 1 patient. The mean nidus volume was 4.7cc (0.5~11.7 cc, SD 3.7 cc). The locations of nidus were in cerebral hemisphere in 11 patients, cerebellum in 2 patients, basal ganglia in 1 patient, and pons in 1 patient respectively. 9 cases were hemorrhagic, and 6 cases were non-hemorrhagic AVMs. The SRS with LINAC is a safe and effective treatment for cerebral AVMs when the follow up period is over 4 years. However, it is recommended to continue to follow up until the draining vein on arterial phase of follow up DSA disappears completely.

• Journal of Korean Neurosurgical Society
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• v.58 no.3
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• pp.184-191
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• 2015

Objective : Anterior communicating artery (AcomA) aneurysms represent the most common intracranial aneurysms and challenging to treat due to complex vascularity. The purpose of this study was to report our experience of endovascular treatment of AcomA aneurysms. Methods : Between January 2003 and December 2013, we retrospectively reviewed the medical records of 134 AcomA aneurysm patients available more than 6 months conventional angiographic and clinical follow-up results. We focused on aneurismal or AcomA vascular characters, angiographic and clinical follow-up results, and retreatment. Results : The rate of ruptured cases was 75.4%, and the small (<10 mm) aneurysms were 96.3%. Based on the subtypes defined by dominance of A1, 79 patients (59%) had contralateral A1 hypoplasia or agenesis. The immediate post-procedural angiography confirmed complete occlusion in 75.4%, partial occlusion in 24.6%. Procedure related complications were observed in 25 (18.6%) patients. Most of the adverse events were asymptomatic. Follow-up conventional angiography at ${\geq}6$ months was performed in all patients (mean 16.3 months) and major recanalization was noted in 6.7% and regrowth in one case. The aneurysm size (p=0.016), and initial treatment results (p=0.00) were statistically significant risk factors related to aneurysm recurrence. An overall improvement in mRS was observed during the clinical follow-up period and no rebleeding episode occurred. Conclusion : This study demonstrated that endovascular treatment is an effective treatment modality for AcomA aneurysms with low morbidity. Patients should take long term clinical and angiographic follow-up in order to assess the recurrence and warrant retreatment, especially ruptured, large, and initially incomplete occluded aneurysms.

• Clinical and Experimental Pediatrics
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• v.52 no.7
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• pp.804-810
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• 2009

Purpose : We investigated whether ictal single-photon emission computed tomography (SPECT) with prolonged injection of technetium-99m (99mTc) ethyl cysteinate dimer during repeated spasms can localize the epileptogenic foci in children with infantile spasms. Methods : Fourteen children with infantile spasms (11 boys, 3 girls; mean age, $2.2{\pm}1.3$ years) were examined. When a cluster of spasms was detected during video electroencephalography (EEG) monitoring, $^{99m}Tc$ ethyl cysteinate dimer was slowly and continuously injected for 2 minutes to determine the presence of ictal SPECT. For 7 children, the ictal and interictal SPECT images were visually analyzed, while for the remaining 7 children, the SPECT images were analyzed using the subtraction ictal SPECT coregistered to magnetic resonance imaging (MRI) (SISCOM) technique. Subsequently, we analyzed the association between the ictal SPECT findings and those of other diagnostic modalities such as EEG, MRI, and positron emission tomography (PET). Results : Increase in cerebral blood flow on ictal SPECT involved the epileptogenic foci in 10 cases6 cases analyzed by visual assessment and 4 analyzed by the SISCOM technique. The ictal SPECT and video-EEG findings showed moderate agreement (Kappa=0.57; 95% confidence interval, 0.18-0.96). Conclusion : Ictal SPECT with prolonged injection of a tracer could provide supplementary information to localize the epileptogenic foci in infantile spasms.

• The Korean Journal of Nuclear Medicine
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• v.22 no.1
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• pp.83-92
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• 1988

The cocktails of two $^{131}I$ labeled Monoclonal antibody (MCAB) (Anti CA 19-9 F$(ab')_2$ + Anti CEA $F(ab')_2$ fragment), which react specially, with human gastrointestinal cancers, were administered to 10 patients with colorectal (7), stomach(2) and pancreas(1) cancer for scintigraphic detection. All patients were known or postoperatively recurrent cases, and serum tumor markers, CA 19-9 and CEA, were measured with immunoradiometric assay, just before immunoscintigraphy (ISG). The tumor marker's level in serum is not correlated with positive tumor uptake in ISG. The sensitivity and specificity of ISG in detection of 21 tumor sites, based on surgery, CT, ultrasonography and pathology, were 90.5% and 100% One case of colon cancer showed gall bladder metastasis, which was neglected on CT study. Tumor/non tumor uptake ratio of radiolabelled antibody were progressively increased from day 3 to day 7 during study. We summerized as follows 1) The use of cocktails of CEA and CA 19-9 MCAB $F(at')_2$ increased sensitivity and specificity in ISG. 2) Delayed imaging (later than 5 days) increases sensitivitv and specificity due to exclusion of nonspecific iodine accumulation in stomach and lung. 3) Second tracer technique is essential for anatomical landmark by use of a double isotope scan, but subtraction technique, a possible source of artifacts, is no longer necessory when delayed imaging is performed. 4) It may be possible to use two MCAB cocktails of CA 19-9 and CEA in Radioimmunodetection of stomach and pancreas cancer. In conclusion, ISG using MCAB cocktails, $F(ab')_2$ fragment of anti CA 19-9 and Anti CEA, provide additional opportunity for tumor localization and detection of colorectal and other G-I cancer, such as stomach and pancreas.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.5
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• pp.426-431
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• 2007

When a high-energy ultrasound propagates through a solid body that contains a crack or a delamination, the two faces of the defect do not ordinarily vibrate in unison, and dissipative phenomena such as friction, rubbing and clapping between the faces will convert some of the vibrational energy to heat. By combining this heating effect with infrared imaging, one can detect a subsurface defect in material in real time. In this paper a realtime detection of the brazing defect of thin Inconel plates using the UIR (ultrasonic infrared imaging) technology is described. A low frequency (23 kHz) ultrasonic transducer was used to infuse the welded Inconel plates with a short pulse of sound for 280 ms. The ultrasonic source has a maximum power of 2 kW. The surface temperature of the area under inspection is imaged by an infrared camera that is coupled to a fast frame grabber in a computer. The hot spots, which are a small area around the bound between the two faces of the Inconel plates near the defective brazing point and heated up highly, are observed. And the weak thermal signal is observed at the defect position of brazed plate also. Using the image processing technology such as background subtraction average and image enhancement using histogram equalization, the position of defective brazing regions in the thin Inconel plates can be located certainly.

• Korean Journal of Community Nutrition
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• v.12 no.6
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• pp.838-853
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• 2007

The aim of this study was to develop various types of a dish frequency questionnaire (DFQ) for estimating the habitual sodium intake and to evaluate the validity of a 125 item dish frequency questionnaire (DFQ 125) with the DFQ 70, DFQ 36 and DFQ 15. For the DFQ 125, one hundred and twenty five dish items were selected based on the information of sodium content of a one serving size, consumption frequency and dish items that contributed most to the variation of sodium intake. Frequency of consumption was determined through nine categories ranging from more than 3 times a day to almost never to indicate how often the specified amount of each food item was consumed during the past 6 months. The sodium intake estimated with DFQ 125 was $5775.0{\pm}3636.3mg$, 12.6% higher than that estimated with a 24 hr urine analysis ($5009.7{\pm}1541.9mg$) and significant correlation was observed between them (r=0.3315, p<0.001). When sodium content in broth leftover was subtracted from the total intake, the actual sodium intakes was decreased to $5309.6{\pm}3076.6mg$, which was 3.2% higher than that with a 24-hr urine analysis. Overall, 56% of subjects in the lowest quintile of sodium intake computed with DFQ 125 were also in the lowest of adjacent quintile while categorization into the opposite quintile were 4.9%. DFQ 70 was developed from DFQ 125 by omitting the food items not frequently consumed, selecting the dish items that showed higher sodium content per one portion size and higher consumption frequency. The sodium intake estimated with DFQ 70 ($5026.6{\pm}3107.1mg$) showed only 0.2% difference from that estimated with a 24-hr urine analysis, significant correlation with it (r=0.3199, p<0.001) and higher proportion of subjects to be classified into the same or adjacent quintile. The sodium intake estimated with DFQ 36 or DFQ 15 was also significancy correlated with that estimated with a 24-hr urine analysis (r=0.3441, p<0.001; r=0.321, p<0.001 respectively) and more. The proportion of subjects was classified into the same or adjacent quintile. However, the actual sodium intake estimated with DFQ 36 or DFQ 15 were $3534.0{\pm}1804.6mg\;and\;2508.0{\pm}1261.5mg$, respectively, 31.3% or 51.3% less than that estimated with a 24-hr urine analysis. It seems the DFQ 125 with subtraction of sodium content in broth leftover or DFQ 70 can be used quantitatively to estimate sodium intake of adults. DFQ 36 or DFQ 15 can be used as a screening tool or to assess the changes of sodium intake after nutrition education.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2000.04a
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• pp.113-119
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• 2000

The Pansori is a Korean traditional vocal music that has a unique story and melody which converts deep emotion into art. It has both verbal and emotional components. which can be coordinated by large-scale neural network. The purpose of this study is to illustrate the cortical network activated by a Korean traditional opera, Pansori, with different emotional valence using functional MRI (fMRI).Nine right-handed volunteers participated. Their mean age was 25.3 and the mean modified Edinburgh score was +90.1. Activation tasks were designed for the subjects to passively listen to the two parts of Pansories with sad or hilarious emotional valence. White noise was introduced during the control periods. Imaging was conducted on a 1.5T Siemens Vision Vision scanner. Single-shot echoplanar fMRI scans (TR/TE 3840/40 ms, flip angle 90, FOV 220, 64 x 64 matrix, 6mm thickness) were acquired in 20 contiguous slices. Imaging data were motion-corrected, coregistered, normalized, and smoothed using SPM-96 software.Bilateral posterior temporal regions were activated in both of Pansori tasks, but different asymmetry between the tasks was found. The Pansori with sad emotion showed more activation in the light superior temporal regions as well as the right inferior frontal and the orbitofrontal areas than in the right superior temporal regions as well as the right inferior frontal and the orbitofrontal areas than in the left side. In the Pansori with hilarious emotion, there was a remarkable activation in the left hemisphere especially at the posterior temporal and the temporooccipital regions as well as in the left inferior and the prefrontal areas. After subtraction between two tasks, the sad Pansori showed more activation in the right temporoparietal and the orbitofrontal areas, in contrast, the one with hilarious emotion showed more activation in the left temporal and the prefrontal areas. These results suggested that different hemispheric asymmetry and cortical areas are subserved for the processing of different emotional valences carried by the Pansories.

• Science of Emotion and Sensibility
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• v.12 no.4
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• pp.425-432
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• 2009

The purposes of the study were to examine cerebellar areas and lateralization responsible for visuospatial and verbal tasks using functional Magnetic Resonance Imaging(fMRI). Eight healthy male college students($21.5\;{\pm}\;2.3$ years) and eight male college students($23.3\;{\pm}\;0.5$ years) participated in this fMRI study of visuospatial and verbal tasks, respectively. Functional brain images were taken from 3T MRI using the single-shot EPI method. All functional images were aligned with anatomical images using affine transformation routines built into SPM99. The experiment consisted of four blocks. Each block included a control task(1 minute) and a cognitive task(1 minute). A run was 8 minutes long. Using the subtraction procedure, activated areas in the cerebellum during the visuospatial and verbal tasks were color-coded by t-score. A cerebellar lateralization index was calculated for both cognition tasks using number of activated voxels. The activated cerebellar regions during the both cognition tasks of this study agree with previous results. Since the number of activated voxels of the left and right cerebellar hemisphere was almost same, there was no cerebellar lateralization for both cognition tasks.