• Title/Summary/Keyword: High beam

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The Palliative Effect of Endobronchial Brachytherapy for Previously Irradiated Patients with Lung Cancer (이전에 외부방사선치료를 받은 폐암 환자에서 기관지내 근접치료의 고식적 효과)

  • Park, Young-Je;Kim, Kwang-Taik;Yang, Dae-Sik;Lee, Suk;Kim, Chul-Yang
    • Radiation Oncology Journal
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    • v.25 no.3
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    • pp.177-184
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    • 2007
  • Purpose: To evaluate the palliative effect of endobronchial brachytherapy (EBB) for patients with lung cancer that previously received external beam radiotherapy (EBRT). Materials and Methods: From July 1992 to May 2003, 29 patients with a recurrent or persistent lung cancer were treated with palliative EBB at our institute. EBB consisted of three fractions (once a week) of a dose of 5 Gy using the high dose-rate remote afterloader. Symptomatic improvement was assessed subjectively, and patients were divided into two groups according to whether symptoms were improved or not. Factors such as age, performance status, duration from EBRT to EBB and the location of the tumor were compared between the improved and unimproved groups of patients. Results: Overall symptomatic improvement was found in 27 out of 52 symptoms (52%). Improvement as to the type of symptoms was seen in 41 %, 50%, 82% and 33% of patients with cough, dyspnea, hemoptysis, and obstructive pneumonia respectively. The rate of improvement of hemoptysis was more than that of cough (p<0.05). The median time to symptom relapse was 5 months. The improved patient group (n=17, 59%) had a better performance status and longer duration from EBRT to EBB than the unimproved patient group (p<0.05). Lesions located in the distal trachea and/or main bronchus were found more frequently in the improved group of patients than in the unimproved group of patients, but the difference was not statistically significant (p=0.06). Fatal complications developed in two patients (7%), which were a hemoptysis and bronchopleural fistula respectively. Conclusion: Symptom improvement was found in 60% of patients after EBB and improvement was maintained for 5 months. Palliative EBB, even when EBRT was given previously, can be effective for a patient that has an endobronchial symptom, such as hemoptysis, and for a patient with good performance and a long duration from previous EBRT to EBB.

A Study of Various Filter Setups with FBP Reconstruction for Digital Breast Tomosynthesis (디지털 유방단층영상합성법의 FBP 알고리즘 적용을 위한 다양한 필터 조합에 대한 연구)

  • Lee, Haeng-Hwa;Kim, Ye-Seul;Lee, Youngjin;Choi, Sunghoon;Lee, Seungwan;Park, Hye-Suk;Kim, Hee-Joung;Choi, Jae-Gu;Choi, Young-Wook
    • Progress in Medical Physics
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    • v.25 no.4
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    • pp.271-280
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    • 2014
  • Recently, digital breast tomosynthesis (DBT) has been investigated to overcome the limitation of conventional mammography for overlapping anatomical structures and high patient dose with cone-beam computed tomography (CBCT). However incomplete sampling due to limited angle leads to interference on the neighboring slices. Many studies have investigated to reduce artifacts such as interference. Moreover, appropriate filters for tomosynthesis have been researched to solve artifacts resulted from incomplete sampling. The primary purpose of this study is finding appropriate filter scheme with FBP reconstruction for DBT system to reduce artifacts. In this study, we investigated characteristics of various filter schemes with simulation and prototype digital breast tomosynthesis under same acquisition parameters and conditions. We evaluated artifacts and noise with profiles and COV (coefficinet of variation) to study characteristic of filter. As a result, the noise with parameter 0.25 of Spectral filter reduced by 10% in comparison to that with only Ramp-lak filter. Because unbalance of information reduced with decreasing B of Slice thickness filter, artifacts caused by incomplete sampling reduced. In conclusion, we confirmed basic characteristics of filter operations and improvement of image quality by appropriate filter scheme. The results of this study can be utilized as base in research and development of DBT system by providing information that is about noise and artifacts depend on various filter schemes.

Analysis of Nutrient Composition of Baechu Kimchi (Chinese Cabbage Kimchi) with Seafoods (수산물을 첨가한 배추김치의 영양성분 분석)

  • Jang, Mi-Soon;Park, Hee-Yeon;Park, Jin-Il;Byun, Han-Seok;Kim, Yeon-Kye;Yoon, Ho-Dong
    • Food Science and Preservation
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    • v.18 no.4
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    • pp.535-545
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    • 2011
  • The nutrient composition, including the proximate composition and the mineral, vitamin, amino acid, and free-amino-acid levels, of baechu kimchi (Chinese cabbage kimchi) to which 14 kinds of seafood (flatfish, yellow corvina, sea beam, pollack gizzard shad, ray, gray mullet, skate, hairtail, anchovy, sea squit, pen shell, scallop, small octopus)were added was analyzed. The seafoods were added to salted cabbage at concentration of 10% (w/w) and the prepared seafood baechu Kimchi (BK) was stored at $5^{\circ}C$ for seven days. The levels of moisture (82.09-88.56%), crude lipid (0.31-0.64%), and crude ash (2.70-3.50%) did not differ much among the samples, but the level of crude protein of the BK-with-seafood samples (2.42-5.15%) was greater than that of the control BK (2%), without seafood. The Fe and Ca contents of BK with flatfish showed the highest values (4.1 and 74 mg/100 g, respectively). The vitamin A contents of BK samples with 14 different kinds of seafood were higher than that of the control BK. Moreover, the BK with sea squit had higher vitamin $B_2$ (0.90 mg/100 g) and vitamin C (8.48 mg/100 g) contents among all the BK-with-different-kinds-of-seafood samples. Total amino acids were detected in all BK-with-seafood samples, most of which had high levels of glutamic acid, aspartic acid, proline and alanine. Glutamic acid was the most abundant of all the amino acids. The major free amino acids were hydroxyproline, glutamic acid, alanine, proline, leucine, and valine, of which hydroxyproline was the most abundant. In conclusion, BK with seafood is thought to be a very good source of protein, which is very important from dietary life of humans.

Comparison of Experimental and Radiation Therapy Planning (RTP) Dose Distributions on Air Cavity (공동(air cavity)의 존재 시 실험적 선량분포와 치료계획상의 선량분포 비교)

  • Kim, Yon-Lae;Suh, Tae-Suk;Ko, Shin-Gwan;Lee, Jeong-Woo
    • Journal of radiological science and technology
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    • v.33 no.3
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    • pp.261-268
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    • 2010
  • This study is compared that the dose distribution by experimentation and radiation therapy planning (RTP) when the air cavity region was treated high energy photon. The dose measurements were performed with a 6 MV photon beam of linear accelerator. The polystyrene and self made acyl phantom were similar to tissue density of the human body. A parallel plate chamber was connected to an electrometer. The measurement setup was SCD (Source Chamber Distance) 100 cm and the distance of surface from air cavity was 3 cm. Absorbed dose of interface were measured by area and height. The percent depth dose were measured presence and absence of air cavity, depth according to a ratio of field size and air cavity size. The dose distribution on planning was expressed to do the inhomogeneity correction. As the area of air cavity was increased, the absorbed dose were gradually reduced. It was slightly increased, when the height of air cavity was changed from 0 cm to 0.5 cm. After the point, dose was decreased. In case of presence of air cavity, dose after distal air cavity interface was more great than absence of air cavity. The rebuild up by field size and area of air cavity occurred for field size, $4{\times}4\;cm^2$, $5{\times}5\;cm^2$ and $6{\times}6\;cm^2$, with fixed on area of air cavity, $5{\times}5\;cm^2$. But it didn't occur at $10{\times}10\;cm^2$ field size. On the contrary, the field size was fixed on $5{\times}5\;cm^2$, rebuild up occurred in area of air cavity, $4{\times}4\;cm^2$, $5{\times}5\;cm^2$. but, it did not occur for air cavity, $2{\times}2\;cm^2$, $3{\times}3\;cm^2$. All of the radiation therapy planning were not occurred rebuild up. It was required to pay attention to treat tumor in air cavity because the dose distribution of planning was different from the dose distribution of patient.

Role of Postoperative Radiation Therapy in the Management of Cervical Cancer (자궁경부암에서 수술 후 방사선치료의 역할)

  • Chun, Ha-Chung;Lee, Myung-Za
    • Radiation Oncology Journal
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    • v.22 no.4
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    • pp.265-270
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    • 2004
  • Purpose: To evaluate the effectiveness of postoperative radiation therapy in cervical cancer patients and define the prognostic factors to affect survival rates. Materials and Methods: Eighty one patients with cervical cancer who were treated with postoperative radiation therapy following surgery at our institution between May 1992 and April 2000 were retrospectivelv analyzed. Forty two patients had stage IB disease, 17 had stage IIA disease, and remaining 22 had stage IIB disease, respectively. Histological examination revealed 76 squamous cell carcinoma and 5 adenocarclnoma. Sixty one patients were noted to have stromal invasion greater than 8 mm and 20 patients were noted to have stromal invasion 7 mm or less. Sixteen patients had parametrial invasion and 65 patients did not. Positive vaginal resection margin was documented in only eight patients and positive lymphovascular invasion was in twelve patients. All of the patients were treated with external beam radiation therapy alone. Majority of the patients were treated with 4 field brick technique to encompass whole pelvis. Total of 5,500 cGy was delivered to the primary surgical tumor bed. Minimum follow up period was four years. Results: Actuarial disease free survival rates for entire group of the patients were 95% and 89% at 2 and 5 years, respectively Five year disease free survival rates for patients with stage IB, IIA, and IIB disease were 97%, 87% and 70%, respectivelv. Local recurrences were documented in 5 patients. Cumulative local failure rate at 3 years was 6% Five year disease free survival rates for patients with stromal invasion greater than 8 mm and 7 mm or less were 88% and 92%, respectively (p>0.05). Five year disease free survival rate for patients with parametrial invasion was significantly lower than those with no invasion (72% vs 92%, p<0.05). Also there was significantly lower survival in patients with positive vaginal resection margin, compared with patients with negative resection margin (64% vs 94%, p<0.05). However, lymphovascular invasion was not a statistically significant prognostic factor Parametrial invasion and positive surgical resection margins were noted to be significant prognostic factors. Conclusions: Postoperative radiation therapy appears to be beneficial in controlling local disease in cervical cancer patients with high pathologic risk factors. Parametrial invasion and positive resection margins were noted to be significant prognostic factors to affect survival and more effective treatment should be investigated in these patients.

The Role of Pelvic Irradiation after Hysterectomy in Early Stage Cervical Carcinoma with Pelvic Nodal Metastasis (림프절 전이를 동반한 초기 자궁경부암에서 수술 후 방사선치료의 역할)

  • Suh, Hyun-Suk
    • Radiation Oncology Journal
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    • v.16 no.4
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    • pp.469-475
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    • 1998
  • Purpose : To determine the role of Pelvic irradiation in stage I or IIA cervical carcinoma with pelvic nodal metastasis after hysterectomy and bilateral pelvic lymphadenectomy. Materials and Methods : This is a retrospective study of 68 cervical carcinoma patients who were found to have pelvic nodal metastasis at hysterectomy and received pelvic irradiation from 1983 to 1996 at Inje University Seoul Paik Hospital. External beam radiation therapy to pelvis was delivered using 4 MeV Linac and intracavitary irradiation was given via vaginal ovoids or cylinders. Five-year survival and disease-free survival were estimated by Kaplan-Meier Method and prognostic factors related to survival were analysed by log-rank test and Cox proportional hazards regression model. Results : Median length of follow-up was 52months. Five-year overall survival and disease-free survival (DFS) were 81.8$\%$ and 81.7$\%$ respectively. Patients with endometrial invasion had a 57.1$\%$ 5-year DFS compared to 87.5$\%$ for those without endometrial invasion (p=0.0074). Multivariate analysis revealed endometrial invasion as an only statistically significant prognostic factor for 5-year DFS. Among total 15 (22$\%$) recurrences. pelvic recurrences occurred in 4 cases and distant metastases occurred in 13 cases. Conclusion : We have been able to confirm previous results demonstrating marked decrease in local recurrence after pelvic irradiation. In view of the high proportion of distant metastasis found in this study, a trial of aggressive adjuvant systemic therapy and irradiation in early stage cervical carcinoma patients with pelvic nodal metastasis, especially with endometrial invasion, appears to be warranted.

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DEM Generation over Coastal Area using ALOS PALSAR Data - Focus on Coherence and Height Ambiguity - (ALOS PALSAR 자료를 이용한 연안지역의 DEM 생성 - 긴밀도와 고도 민감도 분석을 중심으로 -)

  • Choi, Jung-Hyun;Lee, Chang-Wook;Won, Joong-Sun
    • Korean Journal of Remote Sensing
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    • v.23 no.6
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    • pp.559-566
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    • 2007
  • The generation of precise digital elevation model (DEM) is very important in coastal area where time series are especially required. Although a LIDAR system is useful in coastal regions, it is not yet popular in Korea mainly because of its high surveying cost and national security reasons. Recently, precise DEM has been made using radar interferometry and waterline methods. One of these methods, spaceborne imaging radar interferometry has been widely used to measure the topography and deformation of the Earth. We acquired ALOS PALSAR FBD mode (Fine Beam Dual) data for evaluating the quality of interferograms and their coherency. We attempted to construct DEM using ALOS PALSAR pairs - One pair is 2007/05/22 and 2007/08/22, another pair is 2007/08/22 and 2007/10/22 with respective perpendicular baseline of 820 m, 312m and respective height sensitivity of 75 m and 185m at southern of Ganghwa tidal flat, Siwha- and Hwaong-lake over west coastal of Korea peninsula. Ganghwa tidal flat has low coherence between 0.3 and 0.5 of 2007/05/22 and 2007/08/22 pair. However, Siwha-lake and Hwaong-lake areas have a higher coherence value (From 0.7 and 0.9) than Ganghwa tidal area. The reason of difference coherence value is tidal condition between tidal flat area (Ganghwa) and reclaimed zone (Siwha-lake and Hwaong-lake). Therefore, DEM was constructed by ALOS PALSAR pair over Siwha-lake and Hwaong-lake. If the temporal baseline is enough short to maintain the coherent phases and height sensitivity is enough small, we will be able to successfully construct a precise DEM over coastal area. From now on, more ALOS PALSAR data will be needed to construct precise DEM of West Coast of Korea peninsular.

Quantitative Elemental Analysis in Soils by using Laser Induced Breakdown Spectroscopy(LIBS) (레이저유도붕괴분광법을 활용한 토양의 정량분석)

  • Zhang, Yong-Seon;Lee, Gye-Jun;Lee, Jeong-Tae;Hwang, Seon-Woong;Jin, Yong-Ik;Park, Chan-Won;Moon, Yong-Hee
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.5
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    • pp.399-407
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    • 2009
  • Laser induced breakdown spectroscopy(LIBS) is an simple analysis method for directly quantifying many kinds of soil micro-elements on site using a small size of laser without pre-treatment at any property of materials(solid, liquid and gas). The purpose of this study were to find an optimum condition of the LIBS measurement including wavelengths for quantifying soil elements, to relate spectral properties to the concentration of soil elements using LIBS as a simultaneous un-breakdown quantitative analysis technology, which can be applied for the safety assessment of agricultural products and precision agriculture, and to compare the results with a standardized chemical analysis method. Soil samples classified as fine-silty, mixed, thermic Typic Hapludalf(Memphis series) from grassland and uplands in Tennessee, USA were collected, crushed, and prepared for further analysis or LIBS measurement. The samples were measured using LIBS ranged from 200 to 600 nm(0.03 nm interval) with a Nd:YAG laser at 532 nm, with a beam energy of 25 mJ per pulse, a pulse width of 5 ns, and a repetition rate of 10 Hz. The optimum wavelength(${\lambda}nm$) of LIBS for estimating soil and plant elements were 308.2 nm for Al, 428.3 nm for Ca, 247.8 nm for T-C, 438.3 nm for Fe, 766.5 nm for K, 85.2 nm for Mg, 330.2 nm for Na, 213.6 nm for P, 180.7 nm for S, 288.2 nm for Si, and 351.9 nm for Ti, respectively. Coefficients of determination($r^2$) of calibration curve using standard reference soil samples for each element from LIBS measurement were ranged from 0.863 to 0.977. In comparison with ICP-AES(Inductively coupled plasma atomic emission spectroscopy) measurement, measurement error in terms of relative standard error were calculated. Silicon dioxide(SiO2) concentration estimated from two methods showed good agreement with -3.5% of relative standard error. The relative standard errors for the other elements were high. It implies that the prediction accuracy is low which might be caused by matrix effect such as particle size and constituent of soils. It is necessary to enhance the measurement and prediction accuracy of LIBS by improving pretreatment process, standard reference soil samples, and measurement method for a reliable quantification method.

3D Histology Using the Synchrotron Radiation Propagation Phase Contrast Cryo-microCT (방사광 전파위상대조 동결미세단층촬영법을 활용한 3차원 조직학)

  • Kim, Ju-Heon;Han, Sung-Mi;Song, Hyun-Ouk;Seo, Youn-Kyung;Moon, Young-Suk;Kim, Hong-Tae
    • Anatomy & Biological Anthropology
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    • v.31 no.4
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    • pp.133-142
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    • 2018
  • 3D histology is a imaging system for the 3D structural information of cells or tissues. The synchrotron radiation propagation phase contrast micro-CT has been used in 3D imaging methods. However, the simple phase contrast micro-CT did not give sufficient micro-structural information when the specimen contains soft elements, as is the case with many biomedical tissue samples. The purpose of this study is to develop a new technique to enhance the phase contrast effect for soft tissue imaging. Experiments were performed at the imaging beam lines of Pohang Accelerator Laboratory (PAL). The biomedical tissue samples under frozen state was mounted on a computer-controlled precision stage and rotated in $0.18^{\circ}$ increments through $180^{\circ}$. An X-ray shadow of a specimen was converted into a visual image on the surface of a CdWO4 scintillator that was magnified using a microscopic objective lens(X5 or X20) before being captured with a digital CCD camera. 3-dimensional volume images of the specimen were obtained by applying a filtered back-projection algorithm to the projection images using a software package OCTOPUS. Surface reconstruction and volume segmentation and rendering were performed were performed using Amira software. In this study, We found that synchrotron phase contrast imaging of frozen tissue samples has higher contrast power for soft tissue than that of non-frozen samples. In conclusion, synchrotron radiation propagation phase contrast cryo-microCT imaging offers a promising tool for non-destructive high resolution 3D histology.

A Study on the Architectural Characteristic Jang-Dae of Castle in the Joseon Dynasty (조선시대 성곽 장대의 건축특성에 관한 연구)

  • Kim, Ki-hyeon;Chang, Hun-duck
    • Korean Journal of Heritage: History & Science
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    • v.48 no.2
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    • pp.120-141
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    • 2015
  • This paper is a preliminary study of architectural characteristics of Jangdae (general's podium), which shows one of the technical changes in fortification of Joseon Dynasty. As a facility for commands of generals and training for officers and men, it was located inside a fortress. Although it is not certain when the first Jangdae was built, the number of them dramatically increased around 18th century. Since the top priority function of the Jangdae was the prospect, it was installed at the hilly spot with open architecture. In addition, the open structure of Eupseong fortress towers on the riverside banks could simultaneously offer the functions as viewing around and Jangdae. Since Jangdae was also a place for military drills and reviews of soldiers, a wide podium was positioned at the front to muster the soldiers. This feature was standardized in the space organization of Jangdae in Joseon, and a mere podium was installed unless the topographic restrictions allows enough space. On the other hand, as a place for a commander, the hierarchy of the Jangdae was revealed through a variety of architectural characteristics. The hierarchy was assigned to the commander's space through the altitude difference, and diverse ornaments were added to show a sense of class. The floor plan of the Jangdae building can be largely categorized into rectangle and square, and the typical sizes of the former are $5{\times}4$ Kans (traditional measuring unit between two columns) and $3{\times}2$ Kans. Out of these two types, buildings of $5{\times}4$ Kans were found in flat land and eupseong fortresses with large space, and the relatively smaller ones of $3{\times}2$ Kans in mountain fortresses. All buildings of square floor plan had $3{\times}3$ Kans style, and the center Kan was twice wider than the side Kan to make the central space wide. It seems that the purpose was to secure the interior space of the upper story because the center Kan accounts for the floor area of the upper story. Some Jangdae's had internal story to form overhead space. The multi-roofed tower style with eaves attached to the upper and lower story is found exclusively in Jangdae. The buildings shows the Onkanmulim style which extends Naejinju (inner column) of the lower story to be the Byeonju (outer column) of the upper story, and the log-framed floor in the upper floor was structured by inserting the Changbang (connecting beam) between the Naejinju's and joining the log frames. In addition, the towers in eupseong fortresses had log-framed floor in the upper floor by setting up the high Nuhaju (column underneath a roof) and joining Cheongbang to the upper part of the column while it cannot be regarded as multi-roofed because only the upper part has a roof.