• Journal of Sericultural and Entomological Science
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• v.28 no.2
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• pp.28-34
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• 1986

The general combining ability (GCV), the specific combining ability (SCA) and the reciprocal combining ability (RCA) effects wereobtained by 8$\times$8 diallel crosses of the silkworms with four Japanese races and four Chinese races, total eight lines. The result are as follows ; 1. The general combining ability (GVA) effects appeared high significant level in the total and the fifth instar periods (TP, FP), a female and a male cocoon weights (FW, MW), a female and a male cocoon layer weights (FL, ML) and a female and a male cocoon layer ratios (FR, MR). Only the reciprocal combining ability (RCA) effects appeared high significant level in the total and the fifth instar periods (TP, FP). 2. The Japanese original silkworm lines varied in the general combining ability effects from -0.864 to 0.578, and the Chinese original silkworm lines did in ones from -0.570 to 1.018. 3. The specific combining ability effects of the silkworm lines made in order of the crossing types of JL (Japanese lines) $\times$CL (Chinese lines)>CL$\times$JL>JL$\times$JL> CL$\times$CL in a total cocoon weights and a cocoon layer weights. 4. The reciprocal combining ability effects of the silkworm lines was in order of the crossing types of JL$\times$CL>JL$\times$JL> CL$\times$CL>CL$\times$JL in a total cocoon weights and cocoon layer weights.

• Journal of Korean Neurosurgical Society
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• v.45 no.4
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• pp.219-223
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• 2009

Objective : Functional magnetic resonance imaging (fMRI) is frequently used to localize language areas in a non-invasive manner. Various paradigms for presurgical localization of language areas have been developed, but a systematic quantitative evaluation of the efficiency of those paradigms has not been performed. In the present study, the authors analyzed different language paradigms to see which paradigm is most efficient in localizing frontal language areas. Methods : Five men and five women with no neurological deficits participated (mean age, 24 years) in this study. All volunteers were right-handed. Each subject performed 4 tasks, including fixation (Fix), sentence reading (SRI. pseudoword reading (PR), and word generation (WG). Fixation and pseudoword reading were used as contrasts. The functional area was defined as the area(s) with a t-value of more than 3.92 in fMRI with different tasks. To apply an anatomical constraint, we used a brain atlas mapping system, which is available in AFNI, to define the anatomical frontal language area. The numbers of voxels in overlapped area between anatomical and functional area were individually counted in the frontal expressive language area. Results : Of the various combinations, the word generation task was most effective in delineating the frontal expressive language area when fixation was used as a contrast (p<0.05). The sensitivity of this test for localizing Broca's area was 81 % and specificity was 70%. Conclusion : Word generation versus fixation could effectively and reliably delineate the frontal language area. A customized effective paradigm should be analyzed in order to evaluate various language functions.

• Journal of the Korean Society of Radiology
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• v.3 no.2
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• pp.23-26
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• 2009

This study proposed an improved center array-sequencing phase unwrapping (ICASPU) algorithm. 2% agarose phantom dopped with 0.6mM/l MnCl2 was used with clinical 1.5T MRI system and commercial knee coil. Obtained k-space data(raw-data) was transmitted to PC and reconstructed into phase image with MATLAB software. Previous center array-sequence phase unwrapping algorithm wascompared with proposed ICASP algorithm using second order regression analysis. As a result, we found that the amount of error on proposed ICASPU method is less about 5 times than that of previous CASPU method. In this study, we exploit improved Center array-sequence phase unwrapping algorithm and expect to apply to images including phase informations.

• Journal of Biomedical Engineering Research
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• v.28 no.3
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• pp.338-343
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• 2007

BOLD T2*-weighted MR images reflects cortical blood flow and oxygenation alterations. fMRI study relies on the detection of localized changes in BOLD signal intensity. Since fMRI measures the very small modulations in BOLD signal intensity that occur during changes in brain activity, it is also very sensitive to small signal intensity variations caused by physiologic noise during the scan. Due to the complexity of movement of various organs associated with heart beat, it is important to reduce cardiac related noise rather than other physiological noise which could be required with relatively simple method. Therefore, a number of methods have been developed for the estimation and reduction of cardiac noise in fMRI study. But, each method has limitation. In this study, we proposed a new estimation method for brain activities influenced by blood pulsation effect using regression analysis with blood pulsation signal and the correspond slice of fMRI. We could find out that the right anterior cingulate cortex and right olfactory cortex and left olfactory cortex were largely influenced by blood pulsation effect for new method. These observed areas are mostly on the structure of anterior cerebral artery in the brain. That is convinced with that our method would be valid and our new method is easier to apply in practice and reduce computational burden than the retrospective method.

• Journal of Nutrition and Health
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• v.36 no.3
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• pp.280-286
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• 2003

Conjugated linoleic acid (CLA) consists of several geometric isomers of linoleic acid. CLA is found in foods derived from ruminants and exhibits strong anticarcinogenic effects in a variety of animal models. Matrix metalloproteinases (MMPs) play a key role in cancer progression. Specifically, MMP-2 and -9, which hydrolyze the basal membrane type IV collagen, are involved in the initial breakdown of collagen and basement membrane components during tumor growth and invasion. However, the effects of CLA on cancer cell motility and MMP expression and activity are not currently well known. Therefore, the present study examined whether CLA reduces the activity of MMP and cell motility in SW480 and SW620 cells, the human colon cancer cell lines. Gelatin zymography and Western blot analysis revealed that phorbol 12-myristate 13-acetate (PMA) induced the activity and protein expression of Mr 92,000 MMP-9 in both cell lines. To examine whether CLA inhibits the MMP activity, cells were incubated with 100 ngfmL PMA in the presence of various concentrations of CLA. PMA-induced MMP-9 activity was decreased by 20 $\mu$ M CLA in SW480 cells, and by 10 $\mu$ M and 20 $\mu$ M CLA in SW620 cells. Results from the Hoyden chamber assay showed that cell motility was increased by PMA and that PMA-induced cell motility was significantly decreased by 20 $\mu$ M CLA in SW480 cells. These results indicate that CLA may reduce the motility and MMP activity in human colon cancer cells.

• Journal of Korean Neurosurgical Society
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• v.40 no.4
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• pp.245-248
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• 2006

Objective : To evaluate the effectiveness of Novalis shaped beam radiation treatment as an adjuvant treatment in patients with craniopharyngiomas. Methods : We reviewed 8 patients with craniopharyngiomas who had recurring tumors during follow-up or had residual lesions after primary surgery. Three of 8 patients were found to have recurrence after gross total excision of the tumor and 5 patents had residual lesions after subtotal resection. All patients were treated with fractionated stereotactic radiation treatment[FSRT] using Novalis system. The mean age of patients was 28 years [range $16{\sim}52$]. The median irradiation dose per fraction was 17Gy [range $1.7{\sim}2.0$]. The median fraction number was 23 [range $15{\sim}25$], and the median total dose was 39.1 Gy [range $25.5{\sim}42.5$]. Follow-up included MR imaging, and ophthalmologic and endocrine examinations. Results : The median follow-up period was 23 months [range $12{\sim}43$]. The local tumor control rate was 87.5%. One patient had a recurring tumor, in which cystic change developed 2 months after FSRT. Four patients showed a decrease in size of their tumor, while 3 patients remained stable. Seven out of 8 patients had hormonal dysfunction that remained unchanged after initial surgery. No further progression of visual impairment was observed. Conclusion : FSRT using Novais system is effective and safe for the treatment of recurring or residual craniopharyngiomas without toxicity like optic neuropathy.

• Journal of the Korean Society of Propulsion Engineers
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• v.3 no.4
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• pp.44-50
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• 1999

For the prediction of combustion performance of the Unlike Impinging Quadlet Injector (OOOF type), mixing efficiency, mixing characteristic velocity, and efficiency of mixing characteristic velocity were obtained from the cold test. Water/kerosene were used for simulants, The momentum ratio of oxidizer and fuel were mixing correlating parameter. Orifice discharge coefficient, spray pattern and mass distribution were measured. As a result, invasion-depth had strong effect on mixing efficiency, mixing characteristic velocity, and efficiency of mixing characteristic velocity. Mixing efficiency and efficiency of mixing characteristic velocity showed maximum value for momentum ratio 1.67(TMR = 2.5), and fuel rich state showed larger decreasing ratio than oxidizer rich state.

• Nuclear Engineering and Technology
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• v.38 no.3
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• pp.239-250
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• 2006

Computational anthropomorphic phantoms are computer models of human anatomy used in the calculation of radiation dose distribution in the human body upon exposure to a radiation source. Depending on the manner to represent human anatomy, they are categorized into two classes: stylized and tomographic phantoms. Stylized phantoms, which have mainly been developed at the Oak Ridge National Laboratory (ORNL), describe human anatomy by using simple mathematical equations of analytical geometry. Several improved stylized phantoms such as male and female adults, pediatric series, and enhanced organ models have been developed following the first hermaphrodite adult stylized phantom, Medical Internal Radiation Dose (MIRD)-5 phantom. Although stylized phantoms have significantly contributed to dosimetry calculation, they provide only approximations of the true anatomical features of the human body and the resulting organ dose distribution. An alternative class of computational phantom, the tomographic phantom, is based upon three-dimensional imaging techniques such as magnetic resonance (MR) imaging and computed tomography (CT). The tomographic phantoms represent the human anatomy with a large number of voxels that are assigned tissue type and organ identity. To date, a total of around 30 tomographic phantoms including male and female adults, pediatric phantoms, and even a pregnant female, have been developed and utilized for realistic radiation dosimetry calculation. They are based on MRI/CT images or sectional color photos from patients, volunteers or cadavers. Several investigators have compared tomographic phantoms with stylized phantoms, and demonstrated the superiority of tomographic phantoms in terms of realistic anatomy and dosimetry calculation. This paper summarizes the history and current status of both stylized and tomographic phantoms, including Korean computational phantoms. Advantages, limitations, and future prospects are also discussed.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.4
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• pp.330-335
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• 2002

The study was performed to investigate the comparison of relative signal intensity of normal- and abnormal-side retrodiscal tissue, and relationship between clinical examination, joint effusion and relative signal intensity of retrodiscal tissue in patients with unilateral TMJ internal derangement. The study group comprised 19 females and 9 males, with a mean age of 29 years. After measurements of the signal intensity were made on the MR imager for the T2 weighted images on retrodiscal tissue and brain gray matter, we calculated relative value and tried to find relationship between clinical examination, joint effusion and relative signal intensity on normal- and abnormal-side. The results are as follows. 1. The gray matter is an appropriate reference point. 2. The relative signal intensity is high significantly in abnormal-side retrodiscal tissue compared with normal-side retrodiscal tissue. 3. The relative signal intensity is high significantly in painful joints compared with nonpainful joints and in joints with joint effusion compared with joints without joint effusion. 4. The relative signal intensity in normal joints, joints with reduction and joints without reduction is increased in order significantly.

• The Plant Pathology Journal
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• v.34 no.3
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• pp.182-190
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• 2018

Powdery mildew caused by the obligate biotrophic fungus Podosphaera xanthii poses a serious threat to melon (Cucumis melo L.) production worldwide. Frequent occurrences of the disease in different regions of South Korea hints at the potential existence of several races which need to be identified. The races of five isolates collected from different powdery mildew affected regions were identified based on the pathogenicity tests of these isolates on eight known differential melon cultigens namely, SCNU1154, PMR 45, WMR 29, PMR 5, MR-1, PI124112, Edisto 47 and PI414723. None of the isolates have shown same disease responses to those of the known races tested in this study and in previous reports on these identical differential melon cultigens. This indicates that the tested uncharacterized isolates are new races. Among the isolates, the isolates from Hadong, Buyeo, Yeongam and Gokseong have shown same pathogenicity indicating the possibility of these isolates being one new race, for which we propose the name 'race KN1'. The isolate of Janghueng have also shown unique disease response in the tested differential melon cultigens and hence, we identified it as another new race with a proposed name 'race KN2'. Report of these new races will be helpful in taking effective control measures in prevalent regions and for future breeding programs aimed at developing varieties that are resistant to these race(s).