• Title/Summary/Keyword: Radiation stability

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Preparation and Animal Imaging of $^{153}Sm$-EDTMP as a Bone Seeking Radiopharmaceutical (골친화성 방사성의약품 $^{153}Sm$-EDTMP의 합성과 동물영상)

  • Choi, Tae-Hyun;Kim, Se-Jung;Shin, Byung-Chul;Woo, Kwang-Sun;Chung, Wee-Sup;Choi, Chang-Woon;Lim, Sang-Moo
    • The Korean Journal of Nuclear Medicine
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    • v.39 no.1
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    • pp.44-48
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    • 2005
  • Purpose: Ethylenediamine-tetramethylenephosphonic acid (EDTMP) has widely used chelator for the labeling of bone seeking radiopharmaceuticals complexed with radiometals. $^{153}Sm$ can be produced by the HANARO reactor at the Korea Atomic Energy Research Institute, Taejon, Korea. $^{153}Sm$ has favourable radiation characteristics $T1/2=46.7\;h,\;{\beta}_{max}=0.81\;MeV\;(20%),\;0.71\;MeV\;(49%),\;0.64\;MeV\;(30%)\;and\;{\gamma}=103\;keV\;(30%)$ emission which is suitable for imaging purposes during therapy. We investigated the labeling condition of $^{153}Sm$-EDTMP and imaging of $^{153}Sm$-EDTMP in normal rats. Materials and methods: EDTMP 20 mg was solved in 0.1 mL 2 M NaOH. $^{153}SmCl^3$ was added to EDTMP solution and pH of the reaction mixtures was adjusted to 3 and 12, respectively. Radiochemical purity was determined with paper chromatography. After 30 min. reaction, reaction mixtures were neutralized to pH 7.4, and the stability was estimated upto 120 hrs. Imaging studies of each reaction were perfomed in normal rats (37 MBq/0.1 mL). Results: The labeling yield of $^{153}Sm$-EDTMP was 99%. The stability of pH 8 reaction at 60, 96 and 120 hr was 99%, 95%, 89% and that of pH 12 at 36, 60, 96 and 120 hr was 99%, 95%, 88%, 66%, respectively. The $^{153}Sm$-EDTMP showed constantly higher bone uptake from 2 to 48 hr after injection. Conclusion: $^{153}Sm$-EDTMP, labeled at pH 8 reaction condition, has been stably maintained. Image of $^{153}Sm$-EDTMP at 2, 24, 48 hr after injection, demonstrate that $^{153}Sm$-EDTMP is a good bone seeking radiopharmaceuticals.

Evaluation of Clinical Availability for Shoulder Forced Traction Method to Minimize the Beam Hardening Artifact in Cervical-spine Computed Tomography (CT) (경추부 전산화단층촬영에서 선속 경화 인공물을 최소화하기 위한 견부 강제 견인법에 대한 임상적 유용성 평가)

  • Kim, Moonjeung;Cho, Wonjin;Kang, Suyeon;Lee, Wonseok;Park, Jinwoo;Yu, Yunsik;Im, Inchul;Lee, Jaeseung;Kim, Hyeonjin;Kwak, Byungjoon
    • Journal of the Korean Society of Radiology
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    • v.7 no.1
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    • pp.37-44
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    • 2013
  • In study suggested clinical availability to shoulder forced traction method in term of quality of image, the patient's convenience and stability, according to whether to use of shoulder forced traction bend using computed tomography(CT) that X-ray calibration and various mathematic calibration algorithm application can be applied by AEC. To achieve this, 79 patients is complaining of cervical pain oriented that shoulder forced traction bend use the before and after acquires lateral projection scout image and transverse image. transverse image of a fixed size in concern field of pixel and figure the average HU value compare that quantitative analysis. Artifact and pixel and resolution to qualitative clinical estimation image analysis. the patient feel inconvenience degree that self-diagnosis survey that estimate. As a result, lateral projection scout image if you used shoulder forced traction bend for the depicted has been an increase in the number of a cervical vertebrae. transverse image concern field shoulder forced traction bend use the before and after for pixel and the average HU-value changes was judged to be almost irrelevant. Artifact and resolution and contrast, in qualitative analysis of the results relating the observer to the unusual result. So, the patients of 82.27% complained discomfort that use of shoulder forced traction bend in self-diagnosis survey. No merit of medical image by using of bend from result was analyzed quality of image to quantitative and qualitative method judged. Nowadays, CT is supplied possible revision of quality of radiation by reduction of slice and automatic exposure controller, etc and application of preconditioning filter process due to various mathematic revision algorithm. So, image noise by beam hardening artifact should not be a problem. shoulder forced traction bend of use no longer judged clinically availability because have not influence of image quality and give discomfort, have extra dangerousness.

Proteomic Analysis and Growth Responses of Rice with Different Levels of Titanium Dioxide and UV-B (이산화티탄과 UV-B 수준에 따른 벼 생육과 프로테옴 해석)

  • Hong, Seung-Chang;Shin, Pyung-Gyun;Chang, An-Cheol;Lee, Ki-Sang;Lee, Chul-Won;Woo, Sun-Hee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.52 no.1
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    • pp.69-80
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    • 2007
  • Among the photoactive semiconductors such as $TiO_2,\;ZnO,\;Fe_2O_3,\;WO_3,\;and\;CdSe,\;TiO_2$ is the most widely used as photocatalyst in different media, because of its lack of toxicity and stability. In this study, the effects of titanium dioxide were investigated to obtain the information of physiological change in rice plant. Light-adapted Chlorophyll flourescence index decreased and relative electron transport rate of rice leaves was activated by titanium dioxide under $2,400\;{\mu}mol\;m^{-2}\;s^{-1}$ PAR (Photosynthetic active radiation). Relative electron transport rate of rice leaf treated with titanium dioxide 10 ppm was high in order of $2,400\;{\mu}mol\;m^{-2}\;s^{-1}\;PAR,\;2,200\;{\mu}mol\;m^{-2}\;s^{-1}\;PAR,\;450\;{\mu}mol\;m^{-2}\;s^{-1}\;PAR$ and titanium dioxide 10 ppm (45.1%), control (32.4%), diuron 10 ppm (15.3%) under $2,400\;{\mu}mol\;m^{-2}\;s^{-1}\;PAR$. Titanium dioxide increased photosynthesis of the rice leaf under $13.6\;KJ\;m^{-2}\;day^{-1}$ UV-B only. With titanium dioxide 20 ppm, reduced UV-B ($0.15\;KJ\;m^{-2}\;day^{-1}$) intensity changed the induction of proteins and twenty-five proteins were identified. Among them, seventy proteins were up-regulated, four proteins were down-regulated and four proteins were newly synthesized. Function of these proteins was related to photosynthesis (52%), carbohydrate metabolism (4%), stress/defense (8%), secondary metabolism (4%), energy/electron transport (4%), and miscellaneous (28%).

Oxide perovskite crystals type ABCO4:application and growth

  • Pajaczkowska, A.
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1996.06a
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    • pp.258-292
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    • 1996
  • In the last year great interest appears to YBCO thin films preparation on different substrate materials. Preparation of epitaxial film is a very difficult problem. There are many requirements to substrate materials that must be fullfilled. Main problems are lattice mismatch (misfit) and similarity of structure. From paper [1] or follows that difference in interatomic distances and angles of substrate and film is mire important problem than similarity of structure. In this work we present interatomic distances and angle relations between substrate materials belonging to ABCO4 group (where A-Sr or Ca, B-rare earth element, C-Al or Ga) of different orientations and YBCO thin films. There are many materials used as substrates for HTsC thin films. ABCO4 group of compounds is characterized by small dielectric constants (it is necessary for microwave applications of HTsC films), absence of twins and small misfit [2]. There most interesting compounds CaNdAlO4, SrLaAlO4 and SrLaGaO4 were investigated. All these compounds are of pseudo-perovskite structure with space group 14/mmm. This structure is very similar to structure of YBCO. SLG substrate has the lowest misfit (0.3%) and dielectric constant. For preparation of then films of substrates of this group of compound plane of <100> orientation are mainly used. Good quality films of <001> orientations are obtained [3]. In this case not only a-a misfit play role, but c-3b misfit is very important too. Sometimes, for preparation of thin films substrates of <001> and <110> orientations were manufactured [3]. Different misfits for different YBCO faces have been analyzed. It has been found that the mismatching factor for (100) face is very similar to that for (001) face so there is possibility of preparation of thin films on both orientations. SrLaAlO4(SLA) and SrLaGaO4(SLG) crystals of general formula ABCO4 have been grown by the Czochralski method. The quality of SLA and SLG crystals strongly depends on axial gradient of temperature and growth and rotation rates. High quality crystals were obtained at axial gradient of temperature near crystal-melt interface lower than 50℃/cm, growth rate 1-3 mm/h and the rotation rate changing from 10-20pm[4]. Strong anisotropy in morphology of SLA and SLG single crystals grown by the Czochralski method is clearly visible. On the basics of our considerations for ABCO4 type of the tetragonal crystals there can appear {001}, {101}, and {110} faces for ionic type model [5]. Morphology of these crystals depend on ionic-covalent character of bonding and crystal growth parameters. Point defects are observed in crystals and they are reflected in color changes (colorless, yellow, green). Point defects are detected in directions perpendicular to oxide planes and are connected with instability of oxygen position in lattice. To investigate facets formations crystals were doped with Cr3+, Er3+, Pr3+, Ba2+. Chromium greater size ion which is substituted for Al3+ clearly induces faceting. There appear easy {110} faces and SLA crystals crack even then the amount of Cr is below 0.3at.% SLG single crystals are not so sensitive to the content of chromium ions. It was also found that if {110} face appears at the beginning of growth process the crystal changes its color on the plane {110} but it happens only on the shoulder part. The projection of {110} face has a great amount of oxygen positions which can be easy defected. Pure and doped SLA and SLG crystals measured by EPR in the<110> direction show more intensive lines than in other directions which allows to suggest that the amount of oxygen defects on the {110} plane is higher. In order to find the origin of colors and their relation with the crystal stability, a set of SLA and SLG crystals were investigated using optical spectroscopy. The colored samples exhibit an absorption band stretching from the UV absorption edge of the crystal, from about 240 nm to about 550 m. In the case of colorless sample, the absorption spectrum consists of a relatively weak band in the UV region. The spectral position and intensities of absorption bands of SLA are typical for imperfection similar to color centers which may be created in most of oxide crystals by UV and X-radiation. It is pointed out that crystal growth process of polycomponent oxide crystals by Czochralski method depends on the preparation of melt and its stoichiometry, orientation of seed, gradient of temperature at crystal-melt interface, parameters of growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth. Growth parameters have an influence on the morphology of crystal-melt interface, type and concentration of defects.

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Effects of Heat Treatment and Irradiation on Lipid Hydrolysis and Oxidation of Rice Bran (고온처리 및 방사선 조사가 미강 지방질의 가수분해 및 산화에 미치는 영향)

  • Hwang, Keum-Taek;Jung, Soon-Teck
    • Korean Journal of Food Science and Technology
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    • v.28 no.5
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    • pp.928-934
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    • 1996
  • Rice bran, treated with heat or ${\gamma}-radiation$, was stored at $-15^{\circ}C,\;4^{\circ}C,\;37^{\circ}C$ and room temperature to determine its lipid stability by monitoring the changes in moisture, free fatty acids (FFA) and peroxide value (POV). Initial moisture content of rice bran was 14% and decreased with time. The higher storage temperature, the more moisture loss. The moisture content became 9% after 80 days of storage at $37^{\circ}C$. The initial FFA of rice bran was 2.5% which increased with time except the samples stored at $-15^{\circ}C$. The higher storage temperature, the more FFA was produced, by 9 times the initial FAA after 80 days of storage at $37^{\circ}C$. POV increased about twice the initial value after 80 days of storage at $-15^{\circ}C,\;4^{\circ}C$, and room temperature, and 5 times at $37^{\circ}C$. Rice bran was treated with heat at $70^{\circ}C,\;90^{\circ}C\;or\;105^{\circ}C$ and stored for 2 weeks at $30^{\circ}C$: The higher the heat treatment temperature and the longer the heat treatment time, the more moisture was lost. The not show any significant changes. Irradiation at $1{\sim}30\;kGy$ and subsequent storage for 4 weeks at $5^{\circ}C\;or\;30^{\circ}C$ caused negligible changes in moisture content. The FFA contents of rice bran irradiated up to 10 kGy were almost similar to these of nonirradiated one when measured just after irradiation. The samples irradiated at 30 kGy were 1.5 times higher in the FFA contents than nonirradiated ones. But there was little influence of irradiation doses on the FFA contents during storage. Irradiation caused the increase in POV of rice bran. resulting in 4 times increase in case of 30 kGy irradiated sample. During the storage, however, the POV of irradiated rice bran decreased significantly.

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Performance Evaluation of Bio-Membrane Hybrid Process for Treatment of Food Waste Leachate (음식물 침출수 청정화를 위한 파일롯 규모의 생물-분리막 복합공정의 성능 평가 연구)

  • Lee, Myung-Gu;Park, Chul-Hwan;Lee, Do-Hoon;Kim, Tak-Hyun;Lee, Byung-Hwan;Lee, Jin-Won;Kim, Sang-Yong
    • KSBB Journal
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    • v.23 no.1
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    • pp.90-95
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    • 2008
  • In this study, a combined process of sequential anaerobic-aerobic digestion (SAAD), fluidized-bed bioreactor (FBBR), and ultrafiltration (UF) for the treatment of small scale food waste leachate was developed and evaluated. The SAAD process was tested for performance and stability by subjecting leachate from food waste to a two-phase anaerobic digestion. The main process used FBBR composed of aerators for oxygen supply and fluidization, three 5 ton reaction chambers containing an aerobic mesophilic microorganism immobilized in PE (polyethylene), and a sedimentation chamber. The HRTs (hydraulic retention time) of the combined SAAD-FBBR-UF process were 30, 7, and 1 day, and the operation temperature was set to the optimal one for microbial growth. The pilot process maintained its performance even when the CODcr of input leachate fluctuated largely. During the operation, average CODcr, TKN, TP, and salt of the effluent were 1,207mg/L, 100mg/L, 50 mg/L, and 0.01 %, which corresponded to the removal efficiencies of 99.4%, 98.6%, 89.6%, and 98.5%, respectively. These results show that the developed process is able to manage high concentration leachate from food waste and remove CODcr, TKN, TP, and salt effectively.

A Study on the Perception of Concurrent Use of Western and Korean Medicine Care and Integrated Medical Service in Korea - Targeting tertiary hospital users - (의-한의 동시 진료 및 통합의료서비스에 대한 인식조사 - 3차 상급종합병원 이용자를 대상으로 -)

  • Seo, Sangwoo;Kim, Hyungsuk;Lee, Seung Hyeun;Kong, Moonkyoo;Lee, Beom-Joon;Heo, Sung Hyuk;Kwon, Seung-won;Park, Bong Jin;Yun, Dong Hwan;Lee, Euiju;Oh, Hyunjoo;Kim, Sung-Bum;Choi, Hye-Sook;Kim, Kwan-Il;Chung, Won-Seok
    • The Journal of Korean Medicine
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    • v.43 no.2
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    • pp.51-60
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    • 2022
  • Objectives: Currently, Korea's medical services are divided into Western medicine and Korean medicine, and people who are not satisfied with the existing treatments are looking for complementary and alternative medicine(CAM). Therefore, this study attempted to confirm patients' perception of the ongoing collaborative treatment and integrated medical service that added CAM to collaborative treatment based on tertiary hospital users. So that we can confirm the expected advantage and disadvantage of integrated medical service system and the necessity of supporting medical expenses for it. Methods: The survey was conducted on 100 people who experienced tertiary hospital treatment and other 100 people who experienced both tertiary hospital treatment and Korean medicine treatment at the same period. The survey was conducted until the number of respondents in both group reached 100. The survey was conducted through e-mail and was conducted from September 27, 2021 to October 8, 2021. Results: For the advantages of collaborative treatment 'increased in psychological stability,' and for disadvantages 'longer time spent for treatment' were the most common. If integrated medical services are implemented in the future, expected advantages include 'consideration of various treatments.' and expected disadvantages include 'increased medical cost.' The needs to expand support for health insurance for integrated medical services were 75.5% among responders. Conclusions: We were able to find out the (expected) advantages and disadvantages of the collaborative medical care and the integrated medical system that medical users experienced or expected, also confirmed positive answers to the expansion of health insurance support for the integrated medical system.

The Alignment Evaluation for Patient Positioning System(PPS) of Gamma Knife PerfexionTM (감마나이프 퍼펙션의 자동환자이송장치에 대한 정렬됨 평가)

  • Jin, Seong Jin;Kim, Gyeong Rip;Hur, Beong Ik
    • Journal of the Korean Society of Radiology
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    • v.14 no.3
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    • pp.203-209
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    • 2020
  • The purpose of this study is to assess the mechanical stability and alignment of the patient positioning system (PPS) of Leksell Gamma Knife Perfexion(LGK PFX). The alignment of the PPS of the LGK PFX was evaluated through measurements of the deviation of the coincidence of the Radiological Focus Point(RFP) and the PPS Calibration Center Point(CCP) applying different weights on the couch(0, 50, 60, 70, 80, and 90 kg). In measurements, a service diode test tool with three diode detectors being used biannually at the time of the routine preventive maintenance was used. The test conducted with varying weights on the PPS using the service diode test tool measured the radial deviations for all three collimators 4, 8, and 16 mm and also for three different positions of the PPS. In order to evaluate the alignment of the PPS, the radial deviations of the correspondence of the radiation focus and the LGK calibration center point of multiple beams were averaged using the calibrated service diode test tool at three university hospitals in Busan and Gyeongnam. Looking at the center diode for all collimators 4, 8, and 16 mm without weight on the PPS, and examining the short and long diodes for the 4 mm collimator, the means of the validation difference, i.e., the radial deviation for the setting of 4, 8, and 16 mm collimators for the center diode were respectively measured to 0.058 ± 0.023, 0.079 ± 0.023, and 0.097 ± 0.049 mm, and when the 4 mm collimator was applied to the center diode, the short diode, and the long diode, the average of the radial deviation was respectively 0.058 ± 0.023, 0.078 ± 0.01 and 0.070 ± 0.023 mm. The average of the radial deviations when irradiating 8 and 16 mm collimators on short and long diodes without weight are measured to 0.07 ± 0.003(8 mm sd), 0.153 ± 0.002 mm(16 mm sd) and 0.031 ± 0.014(8 mm ld), 0.175 ± 0.01 mm(16 mm ld) respectively. When various weights of 50 to 90 kg are placed on the PPS, the average of radial deviation when irradiated to the center diode for 4, 8, and 16 mm is 0.061 ± 0.041 to 0.075 ± 0.015, 0.023 ± 0.004 to 0.034 ± 0.003, and 0.158 ± 0.08 to 0.17 ± 0.043 mm, respectively. In addition, in the same situation, when the short diode for 4, 8, and 16 mm was irradiated, the averages of radial deviations were 0.063 ± 0.024 to 0.07 ± 0.017, 0.037 ± 0.006 to 0.059 ± 0.001, and 0.154 ± 0.03 to 0.165 ± 0.07 mm, respectively. In addition, when irradiated on long diode for 4, 8, and 16 mm, the averages of radial deviations were measured to be 0.102 ± 0.029 to 0.124 ± 0.036, 0.035 ± 0.004 to 0.054 ± 0.02, and 0.183 ± 0.092 to 0.202 ± 0.012 mm, respectively. It was confirmed that all the verification results performed were in accordance with the manufacturer's allowable deviation criteria. It was found that weight dependence was negligible as a result of measuring the alignment according to various weights placed on the PPS that mimics the actual treatment environment. In particular, no further adjustment or recalibration of the PPS was required during the verification. It has been confirmed that the verification test of the PPS according to various weights is suitable for normal Quality Assurance of LGK PFX.