• Journal of Yeungnam Medical Science
• /
• v.17 no.1
• /
• pp.49-54
• /
• 2000

Background: Echocardiography is rapidly establishing itself as the primary diagnostic technique for investigation of children with heart diseases, and referrals are increasing to the pediatric cardiology clinic for investigation. However, because there is a lack of analyzed data on the patients referred to the pediatric cardiology clinics, we have proceeded to compare and analyze their characteristics to provide basic data base. Methods: From Oct. 1, 1998 to Jul. 10, 1999, total 443 cases referred to the pediatric cardiology clinic of Yeungnam University Hospital were studied retrospectively by medical records, chest X-ray, EKG and echocardiography, etc. Results: The results were as follows. 1. The proportion of male was 61.0%(261 cases) and that of female was 39.0%(67 cases). The ratio of male to female was 1.6:1. The proportion infants less than 1 year-old was 62.6% (26R cases) of all patients. 2. Cardiac murmur was present in 248 cases(57.9%), which was the most common case of referral ed to the pediatric cardiology clinic. The impression at referral was more congenital heart disease(70.6%) than acquired heart disease(17.8%) and arrhythmia01.6%). 3. The final diagnosis was as follows : congenital heart disease was present in 212 cases(49.5%), acquired heart disease, 59 cases(13.9%); arrhythmia. 13 cases(3.0%); normal heart. 144 cases(33.6%). Conclusion: Among the patients referred to pediatric cardiology clinic, 33.6%(144 cases) had normal hearts and why these patients were referred may be possibly due to more dependence on echocardiography than on auscultation instruction. Therefore, clinical and auscultatory skill should be emphasized to minimize dependence on expensive echocardiography for evaluation of pediatric heart disease.

• The korean journal of orthodontics
• /
• v.26 no.1 s.54
• /
• pp.53-63
• /
• 1996

In order In analyze the occlusion of TMD patient, 73 casts and post eroanterior cephalometric X-rays of patients showing TMD symptoms at first interview were measured and compared that of 30 non-patients . Horizental overjet, vertical overbite, openbite, crossbite, depth of curve of Spee, midline deviation, facial asymmetry, attrition, and TPI were measured and processed statistically The results could be summarized as follows, 1. TMD group showed the highest prevalence in twenties, teens, and before 9 years old group in order, and more prevalent in female than male. 2. There were no statistically significance between two groups of overjet and overbite measurements, but showed significance of 6 classification of anterior tooth relationship between two groups TMD groups. 3. n group had more anterior openbite than normal group but there were no statistically significance between two groups. 4. Anterior crossbite was more prevalent in normal group brit posterior crossbite was more prevalent in TMD group. 5. TMD group showed deeper curve of Spee and there were statistically significance between two groups. 6. TMD group had more attrition than normal group and there were statistically significance beween two groups. 7 TMD group showed more facial asymmetry than normal group. 8. TPI did not showed statistical significance beween two groups. According to the above results, TMD group showed severe and complex mode of malocclusion and this should be carefully regarded when treatment planning and during the treatment of malocclusion.

• Radiation Oncology Journal
• /
• v.18 no.2
• /
• pp.107-113
• /
• 2000

Purpose : The goal of this study 닌as to improve the accuracy of three-dimensional conformal radiotherapy (3-D CRT) by measuring the treatment setup error and physiological movement of liver based on the analysis of images which were obtained by electronic portal imaging device (EPID). Materials and Methods : For 10 patients with hepatocellular carcinoma, 4-7 portal images were obtained by using EPID during the radiotherapy from each patient daiiy. We analyzed the setup error and physiological movement of liver based on the verification data. We also determined the safety margin of the tumor in 3-D CRT through the analysis of physiological movement. Results : The setup errors were measured as 3mm with standard deviation 1.70 mm in x direction and 3.7 mm with standard deviation 1.88 mm in y direction respectively. Hence, deviation were smaller than 5mm from the center of each axis. The measured range of liver movement due to the physiological motion was 8.63 mm on the average. Considering the motion of liver and setup error, the safety margin of tumor was at least 15 mm. Conclusion : EPID is a very useful device for the determination of the optimal margin of the tumor, and thus enhance the accuracy and stability of the 3-D CRT in patients with hepatocellular carcinoma.

• Journal of radiological science and technology
• /
• v.34 no.4
• /
• pp.277-285
• /
• 2011

To determine the quality control of UGIS, we acquired 105 patients sampling image at 21 general screening centers. The results of image quality evaluation table containing two countries's UGIS showed that the mean of image qualified education table of our country was 73.3 and the standard error was 4.49; In addition, 19 organizations of 21 general screening centers were given appropriate judgement. The average of image qualified education table of Japan was 58 and the standard error was 4.45. Only 8 organizations were given appropriate judgement. Although we made the image quality evaluation tables with same images, there were many differences in the result of two tables. We figured out the problem about the description of whole stomach and photograph skills. Furthermore, we analysed the situation of the UGIS at each general screening center with the acquired images. The biggest problem of the UGIS of our country was that the procedures were performed without clear medical methods. Methods of UGIS were different at every 21 general screening centers, and most of them did not take exam of anterior surface of stomach of the UGIS. In addition, some general screening centers did not include mucosal relief method or esophagography which is required to include in the image qualified education table of our country. Because polisography is used in the same body position, the problem occured about indiscreet exposure dose of patients. Therefore we have to make an effort to get X-ray images which have enough diagnosis information by the quality control of UGIS.

• Radiation Oncology Journal
• /
• v.13 no.4
• /
• pp.391-396
• /
• 1995

Purpose : The Conformal Radiation Therapy has bee widely used under favour of development of computer technologies. The delivery of a large number of static radiation fields are being necessary for the conformal irradiation. In this paper we investigate dosimetric characteristics on penumbra regions of a multileaf collimator(MLC), and compare to those of lead alloy block for the optimal use of the system in 3-D conformal radiotherapy. Materials and Methods : The measurement of penumbra by MLC or lead alloy block was performed with 6 or 10 MV X-rays. The film was positioned at a dmax depth and 10 cm depth, and its optical density was determined using a scanning videodensitometer. The effective penumbra, the distance from $80{\%}$ to $20{\%}$ isodose lines and $90{\%}$ to $10{\%}$ were analyzed as a function of the angle between the direction of leaf motion and the edge defined by leaves. Results : Increasing MLC angle ($0-75^{\circ}$) was observed with increasing the penumbra widths and the scalloping effect. There was no definite differences of penumbra width from $80{\%}$ to $20{\%}$ isodose lines, while being the small increase of penumbra width from $90{\%}$ to $10{\%}$ isodose line varing the depth and energy. The effective penumbra width of lead alloy block are agree resonably with those of MLC within 4.8mm. Conclusion : The comparative qualitative study of the penumbra between MLC and lead alloy block demonstrate the clinical acceptability and suitability of the multileaf collimator for 3-D conformal radiotherapy.

• Radiation Oncology Journal
• /
• v.17 no.3
• /
• pp.187-194
• /
• 1999

Purpose : The aim of this study is to look for the possible efficacy of external irradiation for locally advanced papillary thyroid cancers (stage pT4 or Nl ). Methods and Materials : From August 1981 through September 1997, 91 Patients with locally advanced papillary thyroid cancers (stage pT4 or Nl ) have been treated with external irradiation and followed up at our clinic. All of the patients have been treated with surgical resection. After surgery, 23 patients received postoperative external irradiation with or without ablative radioiodine therapy, whereas the other 68 patients were treated with ablative radioiodine therapy alone. Distributions of sex, age, and stage were comparable in both irradiated and nonirradiated groups. Multivariate analysis of the influence by age, sex, stage, ablative radioiodine therapy and external irradiation on local control were peformed by using Cox's proportional hazard model. Results : Overall survival rates at 7 years were of no significant difference in both groups. There were $98.1\%$ for no RT group and $90\%$ for RT group (p=0.506). 5-year local control rates were significantly different, these were $95.2\%$ for RT group and $67.5\%$ for no RT group (p=0.0408). An analysis of the prognostic factors, age, sex, stage, and RAI were not significant variables, except for the external irradiation. Conclusion : Adjuvant postoperative external irradiation did not affect overall survival, but significantly improved local control in the patients with locally advanced papillary thyroid cancers (stage pT4 or lympy node involvement).

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.8 no.1
• /
• pp.44-57
• /
• 2003

Seasonal variations of bacterial abundance and production, heterotrophic nanoflagellate (HNF) abundance and HNF ingestion rates on bacteria using FLB together with environmental variables were investigated at intervals of a month in Kyeonggi Bay from December 1991 to November 1998. Bacterial abundance and production ranged from 0.38$\times$10$^{9}$ ~ 3.25$\times$10$^{9}$ cells 1$^{-1}$ (average 1.19$\pm$0.69$\times$10$^{9}$ cells 1$^{-1}$ ) and from 1.51 to 20.4 cells 1$^{-1}$ h$^{-1}$ (average 6.04$\pm$ 1.88$\times$10$^{6}$ cells 1$^{-1}$ h$^{-1}$ ), respectively. Bacterial abundance and production showed no differences at the high tide and low tide, and bacterial abundances were not different with depth, but bacterial production decreased with depth. Seasonal variation of bacterial abundance showed almost similar fluctuation pattern to those of DOC (dissolved organic carbon). HNF abundances ranged from 388 to 4,374 cells ml$^{-1}$ (average 1,344$\pm$130 cells ml$^{-1}$ ), were high in March, April, July and August. HNF abundance showed no difference between the high tide and low tide, and was not different with depth. The ingestion rates of HNF on bacteria were 1.0 to 6.3$\pm$10$^{6}$ bacteria 1$^{-1}$ h$^{-1}$ (average 3.12$\pm$0.55$\times$10$^{6}$ bacteria 1$^{-1}$ h$^{-1}$ ), resulting ingestion rates of HNF removed 19.4 to 141.4 %(average 62.3$\pm$12.0%) of bacterial production. Ingestion rates and grazing pressure of HNF on bacteria showed high correlation with HNF abundance. Although we cannot exactly discussion about seasonal variation of bacteria community in this study area where physical and chemical parameters were very complex, the results indicate that bacterial abundance and production were mainly controlled by resources supply as dissolved organic carbon and chlorophyll-a(bottom-up) except March which bacterial abundance and production uncoupled chlorophyll-a because of low dissolved organic carbon and low temperature, and were controlled by HNF grazing pressure(top-down) in the warm seasons except the winter.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.08a
• /
• pp.134-135
• /
• 2011

양자점은 전자와 양공을 3차원으로 속박 시키므로 기존의 bulk나 양자우물보다 양자점을 이용한 레이저 다이오드의 경우 낮은 문턱 전류, 높은 미분이득 및 온도 안전성의 장점이 있을 거라 기대되고 있다. 그러나, 양자점은 낮은 areal coverage 때문에 높은 속박효율을 얻지 못하고 있다. 이러한 양자점의 문제점을 해결하기 위해 양자점을 양자우물 안에 성장시켜 운반자들의 포획을 향상시키는 방법들이 연구되고 있다. 양자우물 안에 양자점을 넣으면 양자우물이 운반자들의 포획을 증가 시키고, 열적 방출도 억제하여 온도 안정성이 향상 되는 것으로 알려져 있다. 광통신 대역의 1.3 ${\mu}m$ 경우, GaAs계를 이용하여 InAs 양자점을 strained InGaAs 박막을 우물층으로 한 dot-in-a-well 구조의 연구는 몇몇 보고된 바 있다. 그러나 InP계를 사용하는 1.55 ${\mu}m$ 대역에서 dot-in-a-well구조의 연구는 아직 미미하다. 본 연구에서는 유기 금속 화학 증착법(metal organic chemical vapor deposition)을 이용하여 InP 기판 위에 InAs 양자점을 자발성장법으로 성장하였으며 dot-in-a-well 구조에서 우물층으로 1.35 ${\mu}m$ 파장의 $In_{0.69}Ga_{0.31}As_{0.67}P_{0.33}$ (1.35Q)를, 장벽층으로는 1.1 ${\mu}m$ 파장의 $In_{0.85}Ga_{0.15}As_{0.32}P_{0.68}$(1.1Q)를 사용하였다. 양자우물층과 장벽층은 모두 InP 기판과 격자가 일치하는 조건으로 성장하였다. III족 원료로는 trimethylindium (TMI)와 trimethylgalium (TMGa)을 사용하였으며 V족 원료 가스로는 $PH_3$ 100%, $AsH_3$ 100%를, carrier gas로는 $H_2$를 사용하였다. InP buffer층의 성장 온도는 640$^{\circ}C$이며 양자점 성장 온도는 520$^{\circ}C$이다. 양자점 형성은 원자력간 현미경(Atomic force microscopy)를 이용하여 확인하였으며, 박막의 결정성은 쌍결정 회절분석(Double crystal x-ray deffractometry)를 이용하여 확인하였다. 확인된 성장 조건을 이용하여 양자점 시료를 성장하였으며 광여기분광법(Photoluminescence)을 이용하여 광특성을 분석하였다. Fig. 1은 dot in a barrier 와 dot-in-a-well 시료의 성장구조이다. Fig. 1(a)는 일반적인 dot-in-a-barrier 구조로 InP buffer층을 성장하고 1.1Q를 100 nm 성장한 후 양자점을 성장하였다. 그 후 1.1Q 100 nm와 InP 100 nm로 capping하였다. Fig. 1(b)는 dot-in-a-well 구조로 InP buffer층을 성장하고 1.1Q를 100 nm 성장 후 1.35Q 우물층을 4 nm 성장하였다. 그 위에 InAs 양자점을 성장하였다. 그 후에 1.35Q 우물층을 4 nm 성장하고 1.1Q 100 nm와 InP 100 nm로 capping하였다. Fig. 2는 dot-in-a-barrier 시료와 dot-in-a-well 시료의 상온 PL data이다. Dot-in-a-barrier 시료의 PL 파장은 1544 nm이며 반치폭은 79.70 meV이다. Dot-in-a-well 시료의 파장은 1546 nm이며 반치폭은 70.80 meV이다. 두 시료의 PL 파장 변화는 없으며, 반치폭은 dot-in-a-well 시료가 8.9 meV 감소하였다. Dot-in-a-well 시료의 PL peak 강도는 57% 증가하였으며 적분강도(integration intensity)는 45%가 증가하였다. PL 데이터에서 높은 에너지의 반치폭 변화는 없으며 낮은 에너지의 반치폭은 8 meV 감소하였다. 적분강도 증가에서 dot-in-a-well 구조가 dot-in-a-barrier 구조보다 전자-양공의 재결합이 증가한다는 것을 알 수 있으며, 반치폭 변화로부터 특히 높은 에너지를 갖는 작은 양자점에서의 재결합이 증가 된 것을 알 수 있다. 이는 양자우물이 장벽보다 전자-양공의 구속력을 증가시키기 때문에 양자점에 전자와 양공의 공급을 증가시키기 때문이다. 따라서 낮은 에너지를 가지는 양자점을 모두 채우고 높은 에너지를 가지는 양자점까지 채우게 되므로, 높은 에너지를 가지는 양자점에서의 전자-양공 재결합이 증가되었기 때문이다. 뿐만 아니라 파장 변화 없이 PL peak 강도와 적분강도가 증가하고 낮은 에너지 쪽의 반치폭이 감소한 것으로부터 에너지가 낮은 양자점보다는 에너지가 높은 양자점에서의 전자-양공 재결합율이 급증하였음을 알 수 있다. 우리는 이와 같은 연구에서 InP계를 이용해 1.55 ${\mu}m$에서도 dot in a well구조를 성장 하여 더 좋은 특성을 낼 수 있으며 앞으로 많은 연구가 필요할 것이라 생각한다.

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2005.06a
• /
• pp.311-318
• /
• 2005

Transparency on the Total System Performance Assessment (TSPA) is the key issue to enhance the public acceptance for a permanent high level radioactive repository. To approve it, all performances on TSPA through Quality Assurance is necessary. The integrated Cyber R&D Platform is developed by KAERI using the T2R3 principles applicable for five major steps in R&D's. The proposed system is implemented in the web-based system so that all participants in TSPA are able to access the system. It is composed of FEAS (FEp to Assessment through Scenario development) showing systematic approach from the FEPs to Assessment methods flow chart, PAID (Performance Assessment Input Databases) showing PA(Performance Assessment) input data set in web based system and QA system receding those data. All information is integrated into Cyber R&D Platform so that every data in the system can be checked whenever necessary. For more user-friendly system, system upgrade included input data & documentation package is under development. Throughout the next phase R&D, Cyber R&D Platform will be connected with the assessment tool for TSPA so that it will be expected to search the whole information in one unified system.

• Applied Microscopy
• /
• v.29 no.4
• /
• pp.479-491
• /
• 1999

This study was performed to investigate the distribution and differentiation of choline acetyltransferase (ChAT)-immunoreactive cells in the basal nucleus of Meynert of the postnatal and adult rat forebrains, utilizing techniques of immunocytochemistry. According to the cell shape and the ratio of long axis vs short axis of cell soma, the ChAT-immunoreactive nerve cells in the basal nucleus of Meynert of the adult rat were classified into six types. In the adult rat, the frequency distributions (FD) of round, oval, elongated, fusiform, triangular and polygonal cells were 9.4%, 35.5%, 32.1%, 5.9%, 9.1% and 8.0%, respectively. The FD of oval and round nerve cells on the postnatal day (PND) 14 were observed to be 18.7% and 51.5%, respectively. Those were shown to be progressively decreased during developmental process to the adult. Also, those of elongated and triangular nerve cells on the PND 21 were observed to be 30.4% and 10.1%, respectively. Those were shown to be same phenomenon a,1 those in the round and oval cells. Meanwhile, those of the triangular and polygonal nerve cells were progressively increased from the early postnatal stage to the adult. The total mean volumes of ChAT-immunoreactive cell somata in the PND 7 rat were the lowest $(1,083{\mu}m^3)$ and those in the PND 21 rat were shown to be the highest $(5,045{\mu}m^3)$. But in the adult, those were decreased to $(2,731{\mu}m^3)$. Those in the PND 21 rat were shown to be about 84.7% larger than those in the adult. On the electron micrography, the cell organelles such as ribosomes, polysomes, rough endoplasmic reticula (RER) and mitochondria were well developed in the PND 21 rat forebrains, but Golgi complexes were shown to be proliferating phase. Especially, ribosomes, polysomes and RER were immunoreactive in the tissues treated with 0.05% triton X-100. According to the observations in the present study, it is considered that the ChAT-immunoreactive nerve cells in the basal nucleus of Meynert of the rat forebrains are differentiated throughout the following processes of changes during the postnatal development: 1) increase of cell soma volumes with the differentiation of tell organelles and neurites, 2) increase in the FD of differentiated tell types and 3) cell schrinkage without cell loss. The ribosomes, polysomes and RER are considered to be closely related to the intracellular localization and biosynthesis of the ChAT but not Colgi complex.