• Journal of Chest Surgery
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• v.40 no.8
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• pp.552-557
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• 2007

Background: B-type natriuretic peptide (BNP) is a cardiac hormone that is primarily synthesized by the ventricular cardiac myocytes. Increased plasma BNP levels have been observed in patients suffering with congestive heart failure, ventricular hypertrophy and myocaridits and also during heart transplantation rejection. We investigated the serum BNP level as a predictive marker for rejection after heart transplantation. Material and Method: To test the usefulness of measuring the BNP level in cardiac transplant patients, consecutive blood samplings for BNP, right ventricular endomyocardial biopsies, hemodynamic measurements and transthoracic echocardiogram were all done in 10 such patients between January 2004 and August 2005 at the Department of Thoracic and Cardiovascular Surgery in Asan Medical Center. Two groups were identified with using the median value: the low BNP group (n=28, BNP: ${\le}290$ pg/mL) and the high BNP group (n=29, BNP: >290 pg/mL). We retrospectively analyzed rejection, the ejection fraction, tricuspid regurgitation, left ventricular hypertrophy, the pulmonary capillary wedge pressure and the right atrial pressure between the 2 groups. Result: There were no differences in age, gender, rejection, the ejection fraction, tricuspid regurgitation, left ventricular hypertrophy and the right atrial pressure between the 2 groups (p>0.05). However, a higher pulmonary capillary wedge pressure and a higher mean pulmonary atrial pressure were observed in the high BNP group (p<0.05). Further, BNP has linear correlation with the pulmonary capillary wedge pressure (r=0.590, p<0.001). Using the cut-off value of 620 pg/mL, the BNP predicted a high PCWP (>12 mmHg) with a sensitivity of 83.3% and a specificity of 91.1% (AUC: $0.900{\pm}0.045$, p<0.001). Conclusion: The BNP level after heart transplantation does not show any significant correlation with rejection, yet it might be a predictive marker of ventricular diastolic dysfunction.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.4
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• pp.251-261
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• 2003

To measure the GPS position accuracy and its distribution according to the length of the baseline, 30 minutes to 24 hours observations at the fixed location were conducted with two GPS receivers (Ll, 12 channels) on May 29 to June 2, 2002. The GPS data received at the reference station, the rover station and the ordinary times GPS observation station operated by the National Geography Institute in Korea were processed in kinematic and static post-processing methods with a post -processing software. The results obtained are summarized as follows: 1. The number of the satellite that could be observed continuously more than six hours was 16 and most of these satellites were positioned at east-west direction on May 31, 2002. The number of the satellite observed and the geometric dilution of precision (GDOP) determined by the average of every 10 minute for the day were 8 and 3.89, respectively. 2. Both the average GPS positions before and after post-processing were shifted (standalone: 1.17 m, post -processing: 0.43m) to the south and west. The twice distance root mean square (2drms) measured with standalone was 6.65m. The 2drms could be reduced to 33.8% (standard deviation 0=17.2) and 5.3% (0=2.2) of standalone by the kinematic and the static post-processing methods, respectively. 3. The relationship between the length of the baseline x (km) and the 2drms y (m) obtained by the static post-processing method was y=0.00l6x+0.006 $(R^2=0.87)$. In the case of the positioning with the static post-processing method using the GPS receiver, it was found that a positioning within 20cm 2drms was possible when the length of the baseline was less than 100km and the receiving time of the GPS is more than 30 minutes.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.98-105
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• 2017

In this study, the fiber blending ratio and strain rate effect on the tensile behavior of hybrid fiber reinforced cement composite was evaluated. Hooked steel fiber and polyvinyl alcohol fiber were used for reinforcing fiber. The fiber blending ratio of HSF+PVA were 1.5+0.5, 1.0+1.0 and 0.5+1.5vol.%. As a results, the tensile strength, strain capacity and fracture toughness of the hooked steel fiber reinforced cement composites were improved by the increase of the bond strength of the fiber and the matrix according to increase of strain rate. However, the tensile stress sharply decreased after the peak stress because of the decrease in the number of straightened pull-out fibers by micro cracks in the matrix around hooked steel fiber. On the other hand, PVA fiber showed cut-off fracture at strain rate $10^{-6}/s$ with multiple cracks. However, at the strain rate $10^1/s$, the multiple cracks and strain capacity were decreased because of the pull-out fracture of PVA fiber. The HSF1.5PVA0.5 shown the highest tensile strength because the PVA fiber suppressed the micro cracks in the matrix around the hooked steel fiber and improved the pull-out resistance of hooked steel fiber. Thus, DIF of strain capacity and fracture toughness of HSF1.5PVA were greatly improved. In addition, the synergistic response of fracture toughness was positive because the tensile stress was slowly decreased after the peak stress by improvement of the pull-out resistance of hooked steel fiber at strain rate $10^1/s$.

• Sleep Medicine and Psychophysiology
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• v.18 no.2
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• pp.82-86
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• 2011

Objectives: The Berlin Questionnaire (BQ) has been used to help identify patients at high risk of having sleep apnea in primary care. But it has not been validated in a sleep clinic for Korean patients. The aim of this study is to evaluate the usefulness of the BQ as a screening tool for obstructive sleep apnea (OSA) for Korean patients in a sleep clinic. Methods: The BQ was prospectively applied to 121 subjects with OSA suspicion who visited to our sleep clinic. All subjects performed overnight polysomnography. OSA was defined as an apnea-hypopnea index (AHI) ${\geq}5$. We investigated the sensitivity, specificity, positive and negative predictive values of the BQ according to severity by AHI. Results: In 121 subjects, 73.6% were males, with a mean age of $48.8{\pm}13.0$ years. Twenty-five (20.6%) patients did not have OSA (AHI<5), 30 (25%) patients had mild OSA ($AHI{\geq}5$ and <15), 26 (21.4%) had moderate ($AHI{\geq}15$ and <30), and 40 (33%) had severe OSA ($AHI{\geq}30$). The BQ identified 69.4% of the patients as being at high risk for having OSA. The sensitivity and specificity of the BQ were 71.9% and 40%, for $AHI{\geq}5$, 75.8% and 38.2% for $AHI{\geq}15$, 77.5% and 34.6% for $AHI{\geq}30$, respectively. The positive and negative predictive values of the BQ were 82.1% and 27.0% for $AHI{\geq}5$, respectively. Positive and negative likelihood ratios were 1.2 and 0.7, and the overall diagnostic accuracy of the BQ was 65.3%, using an AHI cut-off of 5. Conclusion: Due to modest sensitivity and low specificity, the BQ does not seem to be an appropriate tool for identifying patients with obstructive sleep apnea in a sleep clinic population.

• Tuberculosis and Respiratory Diseases
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• v.55 no.6
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• pp.589-596
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• 2003

Background : The solitary pulmonary nodule(SPN) presents a diagnostic dilemma to the physician and the patients in the our nation with high incidence of tuberculoma. We could not exclude whether the SPN was benign or malignant by the change of the size at chest radiograph and findings of chest CT. Recently, positron emission tomography(PET) have been tried as the differential diagnostic method of SPN. We evaluated the efficacy of PET for differentiating malignant from benign SPN and the relationship between standardized uptake values(SUV) of PET and serum glucose. Method : Between January 2001 and July 2002, sixty-one patients with pulmonary nodule were examined by the chest CT and PET. The SPN has been finally diagnosed by the transthorasic needle aspiration and biopsy, bronchoscopic biopsy, and open lung biopsy. Results : Forty eight patients had a malignant nodule(23 squamous cell lung carcinoma, 16 adenocarcinoma, 9 small cell lung cancer) and thirteen patients had a benign nodule(3 tuberculoma, 9 inflammatory granuloma, 1 cryptococcosis). The mean size of malignant and benign nodule was 40.6 mm and 20.0 mm, respectively. All malignant nodules showed a marked increase in 18 fluorodeoxyglucose (FDG) uptake. Mean SUV of malignant was $9.52{\pm}5.20$ and benign nodule was $1.61{\pm}3.60$. There were false positive cases with an increase in 18-FDG uptake (2 tuberculoma, 1 inflammatory granuloma). The SUV of malignant nodule in diabetes patients has no difference in non diabetes patients($9.10{\pm}4.51$ vs $9.65{\pm}5.46$). The sensitivity and specificity of the PET scan for SPN were 100%, 77%, respectively. The positive and negative predictive values were 94% and 100%. Conclusion : PET scanning showed highly accurate result in differentiating the malignant and benign SPN. There were no significant differences between the SUV and serum glucose in the patients with lung cancer.

• Tuberculosis and Respiratory Diseases
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• v.65 no.4
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• pp.301-307
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• 2008

Background: The triggering receptor expressed on myeloid cells-1 (TREM-1) is an activating receptor that is expressed on the surface of neutrophils and mature monocytes when stimulated with several microbial components, which can amplify the inflammatory response. This study analyzed the prognostic value of the sTREM-1 levels in patients with acute respiratory distress syndrome (ARDS). Methods: The bronchoalveolar lavage (BAL) fluid and blood was collected prospectively from 32 patients with ARDS, 15 survivors and 17 nonsurvivors. An enzyme-linked immunosorbent assay was performed to measure the sTREM-1. The following data was obtained: APACHE II score, Clinical Pulmonary Infection Score (CPIS), BAL fluid analysis, C-reative protein. Mortality in the ICU was defined as the end point. Results: The serum sTREM-1 level was significantly higher in the nonsurvivors than survivors ($54.3{\pm}10.3pg/ml$ vs. $22.7{\pm}2.3pg/ml$, p<0.05). The sTREM-1 level in the serum, but not in the BAL fluid, was an independent predictor of the ICU mortality (OR: 22.051, 95% CI: 1.780~273.148, p<0.016), and a cut-off value of ${\geq}33pg/ml$ yielded a diagnostic sensitivity of 71% and specificity of 93%. Conclusion: The serum sTREM-1 level may be a useful predictor of the outcome of ARDS patients.

• Radiation Oncology Journal
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• v.18 no.4
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• pp.277-282
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• 2000

Purpose : Though It has been known that the to tolerance of the liver to external beam irradiation depends on the irradiated volume and dose, few data exist which Quantify this dependence. However, recently, with the development of three dimensional (3-D) treatment planning, have the tools to Quantify the relationships between dose, volume, and normal tissue complications become available. The objective of this study is to investigate the relationships between normal tissue complication probabili쇼 (WCP) and the risk of radiation hepatitis for patients who received variant dose partial liver irradiation. Materials and Methods : From March 1992 to December 1994, 10 patients with hepatoma and 10 patients with bile duct cancer were included in this study. Eighteen patients had normal hepatic function, but 2 patients (prothrombin time 73$\%$, 68$\%$) had mild liver cirrhosis before irradiation. Radiation therapy was delivered with 10MV linear accelerator, 180$\~$200 cGy fraction per day. The total dose ranged from 3,960 cGy to 6,000 cGy (median dose 5,040 cGy). The normal tissue complication probability was calculated by using Lyman's model. Radiation hepatitis was defined as the development of anicteric elevation of alkaline phosphatase of at least two fold and non-malignant ascites in the absence of documented progressive. Results: The calculated NTCP ranged from 0.001 to 0.840 (median 0.05). Three of the 20 patients developed radiation hepatitis. The NTCP of the patients with radiation hepatitis were 0.390, 0.528, 0.844(median : 0.58$\pm$0.23), but that of the patients without radiation hepatitis ranged fro 0.001 to 0.308 (median .0.09$\pm$0.09). When the NTCP was calculated by using the volume factor of 0.32, a radiation hepatitis was observed only in patients with the NTCP value more than 0.39. By contrast, clinical results of evolving radiation hepatitis were not well correlated with NTCP value calculated when the volume factor of 0.69 was applied. On the basis of these observations, the volume factor of 0.32 was more correlated to predict a radiation hepatitis. Conclusion : The risk of radiation hepatitis was increased above the cut-off value. Therefore the NTCP seems to be used for predicting the radiation hepatitis.

• Journal of Korean Society of Forest Science
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• v.27 no.1
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• pp.5-14
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• 1975

Eroded sloping faces in hillsides including cut-bank slopes are liable to both surface erosion and land-slides and the key to control of these form of erosion lies with drainages of excessive run-off and dense vegetation establishment including surface mulching on the slopes. Micro-plots having $1.6m^2$ (1 metre in width and 1.6 metres in slope length, and 1:1.2 in gradient) of banking slopes on coarse sand soil are used to establish the order of magnititude of the difference in controlling of soil erosion and water runoff, and in rating of survival, performed on the repetetions of three-experiment plots consisted of such three levels as 90% (Dense), 70% (Moderate), and 50% Sparse of the density of the coarse straw-mat mulchings. The main results obtained may be summarized as follows: 1. The rates of surface runoff are calculated as 13.13% from the dense mulchings, 14.21% from the moderate mulchings, and 15.57% from the sparse mulchings respectively. 2. The total amounts of soil loss are measured as about 1.24 tons/ha. from the dense mulchings, about 1.33 tons/ha. from the moderate mulchings, and about 1.44 tons/ha. from the sparse mulchings respectively. The amounts of soil loss under these treatments are much lower than the standard of erosion in USDA (1939 Bennet). 3. Average numbers of germination by treatment are counted as 80 seedlings at the dense mulchings. 132 at the moderates and 121 at the sparse respectively. Large numbers of seedling are suppressed and died during the growing at the dense mulchings due to mainly mechanical obstruction. 4. Coarse straw-mat having about 70% of coverage density is the most suitable mulches in both soil erosion control and vegetation establishment. 5. The method of coarse straw-mat mulching is the most recommendable measure for establishing the vegetation cover with less soil erosion on the denuded gentle slopes in hillsides at present in Korea.

• Tuberculosis and Respiratory Diseases
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• v.55 no.4
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• pp.388-394
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• 2003

Background : Monoclonal antibodies directed against well-known epitopes on cytokeratin (CK) 8, 18 and 19 (Monototal) have been used in the development of a new diagnostic tool for lung cancer. In the mid-1990s, CK 19 fragments (Cyfra 21-1) became popular and widely used for such diagnosis. This is the first study specifically designed to compare these two markers. Method : The serum levels of CK 8, 18 and 19 were measured using two-site monoclonal/polyclonal immunoradiometric assay kit in 57 healthy adults and 289 patients who were admitted to Seoul National University Hospital from May to September, 2002. The lung cancer group comprised 129 primary lung cancer patients; 116 with non-small cell lung cancer(NSCLC) and 13 with small cell lung cancer (SCLC). The control group comprised 160 non-malignant pulmonary lung disease patients and 57 healthy adults. A total of 166 twin Monototal and Cyfra 21-1 serum assays were obtained; 76 with lung cancer, 70 with non-malignant pulmonary lung disease and 20 healthy adults. Results : The mean serum value of Monototal was $412.47{\pm}455.45U/L$ in NSCLC, $237.08{\pm}145.15U/L$ in SCLC, $126.54{\pm}95.72U/L$ in non-malignant pulmonary lung disease, and $63.68{\pm}31.66U/L$ in healthy adults. The serum values of the lung cancer groups were significantly higher than those of the control group (p<0.01). Using a cut off value of 188U/L, sensitivity and specificity was 66.4% and 81.9% in NSCLC, and 43.8% and 81.9% in SCLC, respectively. The serum levels of CK 8, 18 and 19 were higher in advanced NSCLC than in early stage disease. Conclusion : The serum levels of CK 8, 18 and 19 may be useful in the diagnosis of NSCLC.

• Journal of Korean Home Economics Education Association
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• v.29 no.1
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• pp.35-56
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• 2017

The purposes of this study were to develop an instrument to examine the latent domains to measure H-PCK and verify the reliability and validity of the instrument. To accomplish these purposes, instrument item development, content validity, pilot study, and main study were conducted. The results were as follows. First, based on a review of extant literature, 29 items for H-PCK were developed. Seven items were deleted from the original instrument after determining content validity by 10 in-service Home Economics teachers, which resulted in the 22 items of 3 domains(Knowledge of perspective on Home Economics Education(KP), Knowledge of Home Economics curriculum(KC), Knowledge of Home Economics instructional strategies(KI)). Second, data were collected from 137 Home Economics teachers via mail survey for pilot study to establish reliabilities for each individual domain and across the domains based on Cronbach's ${\alpha}$ and item-total correlation. The result showed good reliabilities in the cut-off value of .7 and .5 for Cronbach's ${\alpha}$ and for item-total correlation respectively. Third, the main study was performed with 220 Home Economics teachers via e-mail survey and the reliability and validity tests were conducted. The reliability test results showed good reliabilities. The model for confirmatory factor analysis(CFA) provided a good fit to the data (e.g., CFI=.92, RMSEA=.06, SRMR=.05) to evaluate construct validity. The three domains of KP, KC, and KI demonstrated the acceptable convergent and discriminant validities in each individual domain and over domains. Thus, the instrument in this study may be utilized to measure H-PCK. Finally, criterion-related validity was performed to examine the extent to which the three domains are related to teacher efficacy with Pearson correlation (${\rho}$). It was relatively highly correlated at ${\rho}=.7$. In addition, the higher H-PCK the Home Economics teachers had, the higher teacher efficacy they had. The final instrument consisting of 22 items from 3 domains were determined through the entire procedure.