• Radiation Oncology Journal
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• v.15 no.2
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• pp.145-151
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• 1997

Purpose : To evaluate the loss of bone mineral contents(BMC) in lumbar spine within the radiation field for cervical cancer treatment, BMC in the irradiated patient group was compared with that of a normal control group. Method and materials : Measurements of BMC in the trabecular bone in lumbar spines(L3-L5) were performed in the both patient and normal control groups. Investigators used dual-energy quantitative computerized tomography(DEQCT) using Photon energy of 120 and 80kVp, The numbers of Patient and control groups were 43 in each with age distribution of fifth to seventh decade of women. The numbers of control group were 22 in fifth, 10 in sixth and 11 in seventh decade, those of patient group were 14 in filth, 14 in sixth, and 15 in seventh decade of women. The radiation field was extended to L5 spine for Pelvic irrdiation with 45-54Gy of external radiation dose and 30Gy of high dose rate brachytherapy in cervical cancer, Results : The BMC is decreased as increasing age in both control and patient groups. BMC in lumbar spine of patient group was decreased by about $13\%\;to\;40\%$ maximally. The BMC of L3 and L4 a region that is out of a radiation field for the Patient group demonstrated $119.5\pm30.6,\;117.0\pm31.7\;for\;fifth,\;83.3\pm37.8,\;88.3\pm46.8\;for\;sixth\;and\;61.5\pm18.3,\;56.2\pm26.6mg/cc$ for seventh, Contrasted by the normal control group has shown $148.0\pm19.9,\;153.2\pm23.2\;for\;fifth,\;96.1\pm30.2,\;105.6\pm26.5\;for\;sixth\;and\;73.9\pm27.9,\;77.2\pm27.2mg/cc$ for seventh decade, respectively The BMG of patient group was decreased as near the radiation field, while the lower lumbar spine has shown more large amounts of BMC in the normal control group. In Particular, the BMC of L5 within the radiation field was significantly decresed to $33\%,\;31\%,\;40\%$ compared with the control group of the fifth, sixth and seventh decades, respectively. Conclusion : The pelvic irradiation in cervical cancer has much effected on the loss of bone mineral content of lumbar spine within the radiation field, as the lower lumbar spine has shown a smaller BMC in Patient group with Pelvic irradiation in contrast to that of the normal control groups.

• Radiation Oncology Journal
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• v.27 no.3
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• pp.126-132
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• 2009

Purpose: We wanted to evaluate the prognostic factors for the pathologic N2 non-small cell lung cancer (NSCLC) patients who were treated by postoperative radiotherapy. Materials and Methods: We retrospectively reviewed 112 pN2 NSCLC patients who underwent surgery and postoperative radiotherapy (PORT) From January 1999 to February 2008. Seventy-five (67%) patients received segmentectomy or lobectomy and 37 (33%) patients received pneumonectomy. The resection margin was negative in 94 patients, and it was positive or close in 18 patients. Chemotherapy was administered to 103 (92%) patients. Nine (8%) patients received PORT alone. The median radiation dose was 54 Gy (range, 45 to 66), and the fraction size was 1.8~2 Gy. Results: The 2-year overall survival (OS) rate was 60.2% and the disease free survival (DFS) rate was 44.7% for all the patients. Univariate analysis showed that the patients with multiple-station N2 disease had significantly reduced OS and DFS (p=0.047, p=0.007) and the patients with an advanced T stage ($\geq$T3) had significantly reduced OS and DFS (p<0.001, p=0.025). A large tumor size ($\geq$5 cm) and positive lymphovascular invasion reduced the OS (p=0.035, 0.034). Using multivariate analysis, we found that multiple-station N2 disease and an advanced T stage ($\geq$T3) significantly reduced the OS and DFS. Seventy one patients (63.4%) had recurrence of disease. The patterns of failure were loco-regional in 23 (20.5%) patients, distant failure in 62 (55.4%) and combined loco-regional and distant failure in 14 (12.5%) patients. Conclusion: Multiple involvement of mediastinal nodal stations for the pN2 NSCLC patients with PORT was a poor prognostic factor in this study. A prospective study is necessary to evaluate the N2 subclassification and to optimize the adjuvant treatment.

• Radiation Oncology Journal
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• v.25 no.4
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• pp.268-277
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• 2007

Purpose: Respiratory motion is a considerable inhibiting factor for precise treatment with stereotactic radiosurgery using the CyberKnife (CK). In this study, we developed a moving phantom to simulate three-dimensional breathing movement and investigated the distortion of dose profiles between the use of a moving phantom and a static phantom. Materials and Methods: The phantom consisted of four pieces of polyethylene; two sheets of Gafchromic film were inserted for dosimetry. Treatment was planned to deliver 30 Gy to virtual tumors of 20, 30, 40, and 50 mm diameters using 104 beams and a single center mode. A specially designed robot produced three-dimensional motion in the right-left, anterior-posterior, and craniocaudal directions of 5, 10 and 20 mm, respectively. Using the optical density of the films as a function of dose, the dose profiles of both static and moving phantoms were measured. Results: The prescribed isodose to cover the virtual tumors on the static phantom were 80% for 20 mm, 84% for 30 mm, 83% for 40 mm and 80% for 50 mm tumors. However, to compensate for the respiratory motion, the minimum isodose levels to cover the moving target were 70% for the $30{\sim}50$ mm diameter tumors and 60% for a 20 mm tumor. For the 20 mm tumor, the gaps between the isodose curves for the static and moving phantoms were 3.2, 3.3, 3.5 and 1.1 mm for the cranial, caudal, right, and left direction, respectively. In the case of the 30 mm tumor, the gaps were 3.9, 4.2, 2.8, 0 mm, respectively. In the case of the 40 mm tumor, the gaps were 4.0, 4.8, 1.1, and 0 mm, respectively. In the case of the 50 mm diameter tumor, the gaps were 3.9, 3.9, 0 and 0 mm, respectively. Conclusion: For a tumor of a 20 mm diameter, the 80% isodose curve can be planned to cover the tumor; a 60% isodose curve will have to be chosen due to the tumor motion. The gap between these 80% and 60% curves is 5 mm. In tumors with diameters of 30, 40 and 50 mm, the whole tumor will be covered if an isodose curve of about 70% is selected, equivalent of placing a respiratory margin of below 5 mm. It was confirmed that during CK treatment for a moving tumor, the range of distortion produced by motion was less than the range of motion itself.

• Journal of Preventive Medicine and Public Health
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• v.30 no.4 s.59
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• pp.669-685
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• 1997

Previous studies, reporting the inverse relationship between osteoarthritis and osteoporosis suggest the existence of possible pathophysiologic mechanisms between them. To examinine the hypothesis that 'bone mineral densities of women with osteoarthritis are significantly higher than that of women without osteoarthritis in Korea', subjects from the health and nutritional examination survey in Kuri city were sampled. Samples were selected through multi-stage sampling frame using established clusters in Kuri city. From August 18 to September 10,1997, the survey was conducted. Among the. total number of selected sample population (1,656 people), response .ate was 52.4 percent (348 men and 519 women). 420 women who took BMD measurement, radiologic exam, and anthropometric exam were selected for the analysis. The analytic results are as follows. 1. General characteristics: Mean BMD was $0.493g/cm^2$, mean age was 43.0, mean BMI was $23.9kg/m^2$. The number of women who experienced menopause was 106, hysterectomy was 19. There were 0 case of osteoarthritis of hip, 64 cases of osteoarthritis of knee, and 2 cases of osteoarthritis of hand. 2. Univariate analysis results: Mean BMD of women with the osteoarthritis of knee was significantly lower than that of women without the osteoarthritis of knee(0.4269 vs. $0.5057g/cm^2$). But, there were too few cases of osteoarthritis of hip and hand, so comparative studies of BMD in osteoarthritis of hip and hand could not be conducted. There were significant differences of BMD among pre-menopause group(0.5204), post-menopause group(0.4206), and hysterectomy group(0.4881). Additionally, there were significant differences of BMD among diabetes group(0.4297), impaired glucose tolerance group(0.4874), and normal group(0.5057). Furthermore, age, parity, BMI, bioimpedance were significantly related with BMD. 3. Multivariate analysis results: To examinine the relationship between osteoarthritis and BMD while controlling the other variables' effects which were significant in the univariate analyses, multiple linear regression analysis was done. But, it was found that osteoarthritis of knee was not a significant variable to BMD anymore. While age and menopause had significant negative relationship with BMD. Diabetes, parity, BMI, and bioimpedance did not have significant relationships with BMD. After stratification of subjects according to menopause, multiple linear regression analyses were done to each strata. Consequently, age in post-menopause group, age and osteoarthritis of knee in hysterectomy group showed significant negative relationship with BMD. The results did not support the many results of other previous studies done with white men and women. further studies of biological plausibility to Korean women are recommended. Also it is suggested that longitudinal study to verify the relationship between osteoarthritis and BMD will be valuable.

• The Korean Journal of Nuclear Medicine
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• v.31 no.1
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• pp.73-82
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• 1997

Regional myocardial blood flow (rMBF) can be noninvasively quantified using N-13 ammonia and dynamic positron emission tomography (PET). The quantitative accuracy of the rMBF values, however, is affected by the distortion of myocardial PET images caused by finite PET image resolution and cardiac motion. Although different methods have been developed to correct the distortion typically classified as partial volume effect and spillover, the methods are too complex to employ in a routine clinical environment. We have developed a refined method incorporating a geometric model of the volume representation of a region-of-interest (ROI) into the two-compartment N-13 ammonia model. In the refined model, partial volume effect and spillover are conveniently corrected by an additional parameter in the mathematical model. To examine the accuracy of this approach, studies were performed in 9 coronary artery disease patients. Dynamic transaxial images (16 frames) were acquired with a GE $Advance^{TM}$ PET scanner simultaneous with intravenous injection of 20 mCi N-13 ammonia. rMBF was examined at rest and during pharmacologically (dipyridamole) induced coronary hyperemia. Three sectorial myocardium (septum, anterior wall and lateral wall) and blood pool time-activity curves were generated using dynamic images from manually drawn ROIs. The accuracy of rMBF values estimated by the refined method was examined by comparing to the values estimated using the conventional two-compartment model without partial volume effect correction rMBF values obtained by the refined method linearly correlated with rMBF values obtained by the conventional method (108 myocardial segments, correlation coefficient (r)=0.88). Additionally, underestimated rMBF values by the conventional method due to partial volume effect were corrected by theoretically predicted amount in the refined method (slope(m)=1.57). Spillover fraction estimated by the two methods agreed well (r=1.00, m=0.98). In conclusion, accurate rMBF values can be efficiently quantified by the refined method incorporating myocardium geometric information into the two-compartment model using N-13 ammonia and PET.

• Magazine of the Korean Society of Agricultural Engineers
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• v.11 no.1
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• pp.1561-1579
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• 1969

In Korea, the duty of water in paddy fields was measured at the Agricultural Experimental Station in Suwon about 60 years ago. After that time some testing has been made in several places, but the key points in its experiment were the water depth of evapo-transpiration. Improved breeds, progress in cultivation and management techniques as well as development of measuring apparatus in recent years have necessitated the review of the duty of water in paddy fields. The necessity of reviewing the conventional methods has become even more important, as no source of information has been made available through survey of water utilization on a soil use basis which requires data on peculiar features of the water depth of evapo-transpiration. For example, the duty of water in paddy field is largely affected by the water depth of evapo-transpiration in connection with the wetted paddy field, whereas in connection with the normal paddy fields without this characteristic the vertical percolation become the predominant factor in measuring the decreasing depth of water. Therefore, it becomes important. that not only the water depth of evapotranspiration but also the vertical percolation process should also be observed in order to arrive at a realistic conclusion. As the vertical percolation has aclose relationship to the height of the underground water, the change of the latter can be measured. As the conclusion of this experiment, the following subjects are indicated. 1. In order to determine the economic duty of water in paddy fields on a basis of varying soil features, the varying soil features in the benifited area should be investigated thoroughly. The water depths of evapo-transpiration(ET) ratio to evaporation in the evaporator(V) on a basis of the varying soil features are as follows: clay loam ET/V = 1.11, loam ET/V = 1.64, sandy loam ET.V = 1.63 2. The decreasing depth of water consists of the water depth of evapotranspiration, the vertical per colation and the percolation of foot path. Among these three, the percolation of foot path can be utilized again. 3. As the result of this experiment, it shows the decreasing depth of water as follows. clay loam 9.3 mm/day, loam 13.5mm/daty, sandy loam 15.3mm/day 4. On a basis of the varying soil features and the height of the underground water, the vertical percolation varies. 5. The change of the vertical percolation on a basis of the varying soil features shows as follows: clay loam $1{\sim}2$ mm/day, loam $2{\sim}3$mm/day, sandy loam $3{\sim}4$mm/day 6. The level of the underground water changes sensibly by priority of clay loam, loam, sandy loam. When it rains, the level of the underground water rises fast and falls down slowly. 7. The level of the underground water changes within the scope of 25cm 8. The transpiration ratio is given in table 8 and their value are as follows: clay loam 168.8, loam 255.6, sandy loam 272.5

• Journal of Preventive Medicine and Public Health
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• v.27 no.2 s.46
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• pp.258-273
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• 1994

To compare the physical complaints of vinylhouse farmers with those of non-vinylhouse farmers, a personal interviews on 250 vinylhouse and 142 non-vinylhouse farmers were conducted in Sungjoo county in Kyungpook province selected by a random sampling from July 5 to July 10, 1993. Blood pressure of the subjects was also measured. Vinylhouse farmers had a higher average age, larger family size, shorter experience of farming, more working hours per day and working days per year and higher annual income than the non-vinylhouse farmers. The frequency of pesticide spray of the vinylhouse farmers was 3.4 times on the average in June 1993 as compared with 2.0 times of non-vinylhouse farmers, and 16.7 times for the vinylhouse farmers during the last one year while it was 8.3 times for the non-vinylhouse farmers in the same period. While 39.6% of vinylhouse farmers experienced pesticide intoxication symptoms such as headache, nausea, vomiting, dizziness, itching, and skin irritation, etc. during the month of June, 25.4% of non-vinylhouse farmers experienced such symptoms. The most frequent symptoms among eight symptoms that constitute the farmers' syndrome were lumbago, numbness of hand or foot, shoulder pain and dizziness regardless of sex and type of farming. Prevalence of the farmers' syndrome in male and female among vinylhouse farmers were 22.1%, 43.4%, respectively, and the prevalence in non-vinylhouse farmers was 23.2% for male and 50.7% for female. There was no statistically significant difference in the prevalence of farmers' syndrome between vinylhouse and non-vinylhouse farmers. However, the prevalence in female was about 2 times higher than that of male. When the effects of other factors were adjusted by multiple logistic regression for farmers' syndrome, the prevalence in female was 3.0 times higher than that of male. The prevalence of farmers' syndrome was increased as the age of farmers increased in both vinylhouse and non-vinylhouse farmers, and adjusted odds ratio of farmers' syndrome increased by 3% as the age increased by 1 year. Adjusted odds ratio for Farmers' syndrome in farmers who experienced pesticide intoxication during the month of June was 3.1 times higher than that of farmers who did not have such experience. While the prevalence of hypertension in male and female non-vinylhouse farmers were 22.4%, 13.7%, respectively, the prevalence in vinylhouse farmers were 13.5% for male and 12.0% for female. However, there was no association between farmers' syndrome and hypertension. It was found in this study that the vinylhouse farmers are at a high risk of pesticide intoxication, which is associated with tile common physical complaints. To reduce such risk it is necessary to develop farming methods which do not require the pesticide or may use less pesticide, a safer method of pesticide spraying, and the protective equipments which can be worn at a high temperature and have a better protective effect. Also education of farmers for the correct methods of ventilation after pesticide spraying in the vinylhouse and wearing the protective equipments may be considered as a supportive method. Since inappropriate posture at work and intensive labor may cause farmers' syndrome, it is recommended to develop farming tools which reduce physical burden and take a rest and exercise periodically during work. It is necessary to strengthen the hypertension management program of the Kyungpook province, because the prevalence of hypertension was as high as about 15%.

• Radiation Oncology Journal
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• v.16 no.2
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• pp.99-106
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• 1998

Purpose : We conducted clonogenic assay using human cancer cell lines (MKN-45, PC-14, Y-79, HeLa) to investigate a correlation between the parameters of radiosensitivity. Materials and Methods : Human cancer cell lines were irradiated with single doses of 1, 2, 3, 5, 7 and 10Gy for the study of radiosensitivity and subrethal damage repair capacity was assessed with two fractions of 5Gy separated with a time interval of 0, 1, 2, 3, 4, 6 and 24 hours. Surviving fraction was assessed with clonogenic assay using $Sperman-H\"{a}rbor$ method and mathematical analysis of survival curves was done with linear-quadratic (LQ) , multitarget-single hit(MS) model and mean inactivation dose$(\v{D})$. Results : Surviving fractions at 2Gy(SF2) were variable among the cell lines, ranged from 0.174 to 0.85 The SF2 of Y-79 was lowest and that of PC-14 was highest(p<0.05, t-test). LQ model analysis showed that the values of $\alpha$ for Y-79, MKN-45, HeLa and PC-14 were 0.603, 0.356, 0.275 and 0.102 respectively, and those of $\beta$ were 0.005, 0.016, 0.025 and 0.027 respectively. Fitting to MS model showed that the values of Do for Y-79. MKN-45, HeLa and PC-14 were 1.59. 1.84. 1.88 and 2.52 respectively, and those of n were 0.97, 1.46, 1.52 and 1 69 respectively. The $\v{D}s$ calculated by Gauss-Laguerre method were 1.62, 2.37, 2,01 and 3.95 respectively So the SF2 was significantly correlated with $\alpha$, Do and $\v{D}$. Their Pearson correlation coefficiencics were -0.953 and 0,993. 0.999 respectively(p<0.05). Sublethal damage repair was saturated around 4 hours and recovery ratios (RR) at plateau phase ranged from 2 to 3.79. But RR was not correlated with SF2, ${\alpha}$, ${\beta}$, Do, $\v{D}$. Conclusion : The intrinsic radiosensitivity was very different among the tested human cell lines. Y-79 was the most sensitive and PC-l4 was the least sensitive. SF2 was well correlated with ${\alpha}$, Do, and $\v{D}$. RR was high for MKN-45 and HeLa but had nothing to do with radiosensitivity parameters. These basic parameters can be used as baseline data for various in vitro radiobiological experiments.

• Journal of the Korean Wood Science and Technology
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• v.2 no.2
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• pp.5-7
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• 1974

1. This study indicates that above the fiber saturation point the drying rate can be increased with increasing the velocity of the air circutation, i.e., the drying rate of sample boards is proportional to the air velocity, but below the fiber saturation point, the effect of the velocity of air circulation is very low as shown in Figs. 1 and 2. 2. Under the controlled temperature and humidity in the kiln, the more the sample boards have moisture, the higher drying rate of it can be obtained. In other words, this means that even though in the case of drying various moisture content of wood, at the final drying stage, approximately the same percentage of moisture content of wood can be secured by employing the higher velocity of air circulation. 3. This study shows that the rate of drying in kiln changes distinctly at the fiber saturation point, i, e., above the fiber saturation point, the drying curve shows concave aginst the X axsis, but below the fiber saturation point, in the range from 30 percent of moisture content to 20 percent of moisture content, the curve shows convex as shown in Fig. 3. As the drying progresses, however, the drying curve shows concave again below 20 percent of moisture content. This means that inflection point of drying curve may be located clearly at the fiber saturation point, i.e., 30 percent of moisture content. As mentioned above, the 30 percent of moisture content of wood at which the inflectional point appears can be recognized as a critical point, i. e., the fiber saturation point at which all free water was removed from wood. The existence of inflectional point indicates that the evaporation of hygroscopic water in a cell wall is more difficult than the evaporation of free water in a cell cavity and the minor space of cell wall. The convex curve in the range of moisture content from 30 percent to 20 percent means that the evaporation of capillary condensed water has a tendency of the same rates of drying approximately, but as approaching to the 20 percent of moisture, the transfusion of moisture from wood becomes difficult because of having less moisture in cell wall. Below 20 percent of moisture content, the drying curve shows concave again, which means that it is difficult to remove the moisture located nearer to the surface of cellulose molecules and the surface bound water. These relations were revealed in Fig. 4. In comparison AC curve which does not have the two inflection points with BD curve which has two inflection points, i.e., Band D, they are mentioned already, by existence of the inflection points, the curve BD shows that the change of drying rate in the interval from 20 percent of moisture content to 30 percent of moisture content is not greater than in the case of the curve AC in the same interval. At the inflection point of 30 percent of moisture content, it can be noticed that the changing of the drying rate is very conspicuous. This phenomenon also can be recognized, as it is noticed by the Fig. 3, the drying rate from green to 30 percent of moisture content is very great. But the inclination of the curve is very slow from 30 percent of moisture content to 20 percent of moisture content, i.e., the inclination of the curve becomes almost horizontal lines. Acknowledgments Gratitude is expressed to Fred E. Dickinson, Professor of 'Wood Technology, School of Natural Resources, University of Michigan, USA for his suggestion to carry out this study.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.4
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• pp.323-329
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• 2009

Purpose: Radioimmunoassay (RIA) was usually performed by the batch assay. To improve the efficiency of RIA without increase of the cost and time, random assay could be a choice. We investigated the possibility of the random assay using automatic dispenser by assessing the agreement between batch assay and random assay. Materials and Methods: The experiments were performed with four items; Triiodothyronine (T3), free thyroxine (fT4), Prostate specific antigen (PSA), Carcinoembryonic antigen (CEA). In each item, the sera of twenty patients, the standard, and the control samples were used. The measurements were done 4 times with 3 hour time intervals by random assay and batch assay. The coefficient of variation (CV) of the standard samples and patients' data in T3, fT4, PSA, and CEA were assessed. ICC (Intraclass correlation coefficient) and coefficient of correlation were measured to assessing the agreement between two methods. Results: The CVs (%) of T3, fT4, PSA, and CEA measured by batch assay were 3.2$\pm$1.7%, 3.9$\pm$2.1%, 7.1$\pm$6.2%, 11.2$\pm$7.2%. The CVs by random assay were 2.1$\pm$1.7%, 4.8$\pm$3.1%, 3.6$\pm$4.8%, and 7.4$\pm$6.2%. The ICC between the batch assay and random assay were 0.9968 (T3), 0.9973 (fT4), 0.9996 (PSA), and 0.9901 (CEA). The coefficient of correlation between the batch assay and random assay were 0.9924(T3), 0.9974 (fT4), 0.9994 (PSA), and 0.9989 (CEA) (p<0.05). Conclusion: The results of random assay showed strong agreement with the batch assay in a day. These results suggest that random assay using automatic dispenser could be used in radioimmunoassay.