• Title/Summary/Keyword: the field of radiation use

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Prediction of radiation dose to adult human from radiopharmaceutical manufactured by third generation bisphosphonate labeled with Rhenium

  • Zahra Pourhabib;Hassan Ranjbar
    • Nuclear Engineering and Technology
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    • v.55 no.2
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    • pp.669-673
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    • 2023
  • Introduction: The crucial step in preclinical process of radiopharmaceutical production is internal dosimetry evaluation by different ways to realize radiobiological dose-response relationships and to extract the results for clinical use. Till now several bone-seeking radiopharmaceuticals have been developed for bone metastasis. Interesting features of bisphosphonates attracted attentions to them in the field of radiopharmaceutical therapy and studies on new generation of them have been doing too. Materials and methods: In this study, we used ZNA as representative of the third generation. The radiopharmaceutical 188Re-ZNA was produced and its radiochemical purity was investigated. Then, the biological distribution of the produced radiopharmaceutical at 1, 2, 4 and 24 h after injection on different organs of mice were investigated. Finally, the absorbed dose of organs in the human body was assessed using the RADAR method. Results: The results show 96% radiochemical purity of the 188Re-ZNA radiopharmaceutical. The amount of %ID/g in bone is 1.131% after 1 h and in 24 h it has a significant amount compared to other organs, that is 0.516%. Also dosimetric results show that the highest absorption dose is related to bone and the amount of this dose is 0.050 mGy/MBq. Conclusion: Considering the possibility of producing the 188Re-ZNA radiopharmaceutical, as well as the proper distribution of this radiopharmaceutical in target and non-target organs and increasing the absorbed dose in bone, it can be concluded that this radiopharmaceutical can be useful in the "radiopharmaceutical therapy" in metastases.

Looking Back over a Decade "Final Decision Call after the Accidents of the Fukushima Nuclear Power Plant"

  • Nakajima, Isao;Kurokawa, Kiyoshi
    • Journal of Multimedia Information System
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    • v.7 no.2
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    • pp.147-156
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    • 2020
  • The author Nakajima was involved in the field of disaster communications and emergency medical care as guest research scientist at the Fukushima Nuclear Accident Independent Investigation Commission established by the National Diet of Japan and reviewer of the Commission's report, and Kurokawa was the chairman of this Commission. Looking back over a decade, we are on the liability issue of bureaucrats and telecom operators, so it's becoming clear what was hidden at the time. The battery of NTT DoCoMo's mobile phone repeaters had a capacity of only about 24 hours, and communication failures increased after one day. The Government also failed to issue an announcement of "Vent from reactor" under the Telecommunications Act Article No. 129. This mistake lost the opportunity to use the third-party telecommunications (e.g. taxi radios). Furthermore, as a result of LASCOM (telecommunications satellite network for local governments via GEO) and a variety of unexpected communication failures, the evacuation order "Escape!" could not be notified to the general public well. As a result, the general public was exposed to unnecessary radiation exposure. Such bureaucratic slow action in emergencies is common in the response to the 2020 coronavirus.

A Study on Microwave-FM-CW Detection System for the Sutomatic Optimal Point Traffic Control (교통신호의 자동최적점제어를 위한 마이크로파 FM-CW 검지계통에 관한 연구)

  • 양흥석;김호윤
    • 전기의세계
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    • v.22 no.1
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    • pp.35-41
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    • 1973
  • An automatic point traffic control method is recommended for more idealistic traffic flow over coarse road netowrks. The automatic control apparatus recommended, consists of a transceiver, amplifier, digital-to-analog converter, signal light controller for emergency and steady state, and digital counter as monitor. The transmitter sends a signal to the target vy means of Microwave-FM-CW and a diode detector picks up the echo signal. Thus the operation of the entire system will be carried out through an open loop state. Some factors necessary for an ideal detector system are rapid response, longevity and stability. An analytical method of the Doppler effect substitutes the conventional frequency deviation into the amplitude of detector output. The changing rate of amplitude is proportional to the voltage of the detector output. Some induced formula from Maxwell's radiation field theory ensures this new method, and, new method, and proves the fact with an experimental data presentation. Stability depends upon Klystron as an oscillator and a diode as a detector. the transceiver installation affects on the response and sensitivity of the system. In accordance with the detector output, several targets are easily classified by amplitudes on the scope. The traffic flow, i.e., target movement which is analyzed by the amplitude method, is shown through the scope and indicates it on the digital counter. The best efficiency for the amplitude analysis can be attained through use of an antenna having the highest sensitivity.

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The Role of Air-Vacuum Cushion Device in Patients with Rectal Cancer in Radiation Therapy (직장암 환자에서 방사선치료시 Air-vacuum Cushion의 유용성)

  • Kim Ki-Hwan;Cho Moon-June;Kang No-Hyun;Kim Dong-Wuk;Kim Jun-Sang;Jang Ji-Young;Kim Jae-Sung
    • Radiation Oncology Journal
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    • v.19 no.3
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    • pp.287-292
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    • 2001
  • Prupose : We analyzed setup errors induced by using air-vacuum cushion as immobilization device in patients with rectal cancer. Materials and methods : We had treated the twenty patients with rectal cancer by 6 MV, 10 MV X-ray from Aug. 1998 to Aug. 1999 at Chungnam National University Hospital. All patients were treated at prone position. They were separated to two groups, control group, 10 patients using styrofoam, and test group, 10 patients using styrofoam and air-vacuum cushion. We measured errors of posterior field for x, y axis and lateral field for z, y axis with simulation film and EPID image using a matching technique. Results : In control group, the mean displacement values of pelvic bone landmark for x axis and y axis were 0.02 mm. 0.78 mm, respectively and the standard deviations of systematic error were 2.13 mm, 2.40 mm, respectively and the standard deviation of random error were 1.46 mm. 1.51 mm, respectively. In test group, the mean displacement values of x axis and y axis were -0.33 mm. 0.81 mm, respectively and the standard deviations of systematic error were 1.71 mm, 3.08 mm, respectively and the standard deviations of random errors were 1.40 mm. 1.88 mm, respectively. The mean displacement values of z axis and y axis were 2.98 mm. 0.74 mm, respectively and the standard deviations of systematic error were 4.75 mm, 2.65 mm, respectively and standard deviations of random error were 2.69 mm. 1.86 mm, respectively. The statistical difference of field size by using air vacuum cushion between two groups in posterior direction and lateral direction was not shown. Conclusion : We think that use of air-vacuum cushion may not be an advantage for improving setup accuracy in rectal cancer patients.

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Implementation of Water Bolus in Patient with Large Tissue Defect (조직결손이 큰 환자에서 물 볼루스의 적용에 관한 고찰)

  • Park, Hyo-Kuk;Lee, Sang-Kyu;Yoon, Jong-Won;Cho, Jeong-Hee;Kim, Dong-Wook;Kim, Joo-Ho
    • The Journal of Korean Society for Radiation Therapy
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    • v.18 no.2
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    • pp.105-112
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    • 2006
  • Purpose: To demonstrate that water bolus in the patient surface can decrease the dose inhomogeneity by patient surface large tissue defect when the surface is in an electron-beam field. And We tried to find a easy way to water control. Methods and Materials: To demonstrate the use of water bolus in the irregular surface clinically, the case of a patient with myxofibrosarcoma of the chest wall who was treated with electrons. We obtained dose distribution using missing tissue option of PINACLE 6.2b (ADAC, USA). We fabricate a Mev-green for water bolus in patient with defect of tissue. Then put the water bolus which is vinyl packed water into the designed Mev-green. We peformed CT scan with CT-simulator. Three-dimensional (3D) dose distributions with and without water bolus in the large irregular chest wall were calculated for a representative patient. Resulting dose distributions and dose-volume histograms of water bolus were compared with missing tissue option and non bolus plans. We fabricate a new water control device. Results: Controlled Water bolus markedly decrease the dose heterogeneity, and minimizes normal tissue exposure caused by the surface irregularities of the chest wall mass. In the test case, The non bolus plan has a maximum target dose of 132%. After applying water bolus, the maximum target dose has been reduced substantially to 110.4%. The maximum target dose was reduced by 21.6% using this technique. Conclusion: The results showed that controlled water bolus could significantly improve the dose homogeneity in the PTV for patients treated with electron therapy using water control device. This technique may reduce the incidence of normal organ complications that occur after electron-beam therapy in irregular surface. And our new device shows handiness of water control.

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Analysis of Bone Mineral Density and Related Factors after Pelvic Radiotherapy in Patients with Cervical Cancer (골반부 방사선 치료를 받은 자궁경부암 환자의 골밀도 변화와 관련 인자 분석)

  • Yi, Sun-Shin;Jeung, Tae-Sig
    • Radiation Oncology Journal
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    • v.27 no.1
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    • pp.15-22
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    • 2009
  • Purpose: This study was designed to evaluate the effects on bone mineral density (BMD) and related factors according to the distance from the radiation field at different sites. This study was conducted on patients with uterine cervical cancer who received pelvic radiotherapy. Materials and Methods: We selected 96 patients with cervical cancer who underwent determination of BMD from November 2002 to December 2006 after pelvic radiotherapy at Kosin University Gospel Hospital. The T-score and Z-score for the first lumbar spine (L1), fourth lumbar spine (L4) and femur neck (F) were analyzed to determine the difference in BMD among the sites by the use of ANOVA and the post-hoc test. The study subjects were evaluated for age, body weight, body mass index (BMI), post-radiotherapy follow-up duration, intracavitary radiotherapy (ICR) and hormonal replacement therapy (HRT). Association between the characteristics of the study subjects and T-score for each site was evaluated by the use of Pearson's correlation and multiple regression analysis. Results: The average T-score for all ages was -1.94 for the L1, -0.42 for the L4 and -0.53 for the F. The average Z-score for all ages was -1.11 for the L1, -0.40 for the L4 and -0.48 for the F. The T-score and Z-score for the L4 and F were significantly different from the scores for the L1 (p<0.05). There was no significant difference between the L4 and F. Results for patients younger than 60 years were the same as for all ages. Age and ICR were negatively correlated and body weight and HRT were positively correlated with the T-score for all sites (p<0.05). BMI was positively correlated with the T-score for the L4 and F (p<0.05). Based on the use of multiple regression analysis, age was negatively associated with the T-score for the L1 and F and was positively correlated for the L4 (p<0.05). Body weight was positively associated with the T-score for all sites (p<0.05). ICR was negatively associated with the T-score for the L1 (p<0.05). HRT was positively associated with the T-score for the L4 and F (p<0.05). Conclusion: The T-score and Z-score for the L4 and F were significantly higher than the scores for the L1, a finding in contrast to some previous studies on normal women. It was thought that radiation could partly influence BMD because of a higher T-score and Z-score for sites around the radiotherapy field. We suggest that a further long-term study is necessary to determine the clinical significance of these findings, which will influence the diagnosis of osteoporosis based on BMD in patients with cervical cancer who have received radiotherapy.

The EMI Suppression Technology for Radiated Emissions from PCB Traces (PCB 선로에서 복사되는 불요전자파를 억제하기 위한 기술)

  • 박이섭;이중근
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.11 no.7
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    • pp.1121-1127
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    • 2000
  • Among many EMI suppression techniques for radiated emissions from PCB traces, image technique is adapted in this paper. A model for the analysis of the effect of image plane on the radiation of a microstrip trace is presented. After a simulation was carried out by using the FEM(Finite Element Method), field strength was measured with electric probe. The radiated emission levels were measured for various image plane width, separation distances, and their results show that the measured data are very close to those of simulation result. It proves that a proper use of image planes on the PCBs is very effective means of reducing EMI emissions on the PCBs.

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Radiotherapy for Benign Diseases (양성질환의 방사선치료)

  • Choi, Sang Gyu
    • Journal of the Korean Society of Radiology
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    • v.10 no.8
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    • pp.611-618
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    • 2016
  • Radiotherapy, as a major 3 standard treatment for cancer, traditionally it has been useful treatment that aim of curative or palliative setting. In addition to some proliferative or inflammatory benign disease are also included in field of radiotherapy. Unlike cancer, in the case of benign disease, it shows good treatment result from usage of some medication, conservative management or surgery. But if fail of these treatment or impossible, low dose radiotherapy is use adjuvant or replacement treatment so that there are no harmful side effect result in safety and easy management for reduce pain or recurrence. Recently, the technical advances in radiotherapy that have been achieved make preservation of normal tissue and the clinical application of high precision radiotherapy focus to selective lesions is possible, and it makes useful treatment in senile patients especially.

Superconducting magnet system of in-flight separator for a heavy ion accelerator planned in Korea

  • Kim, J.W.;Kim, D.G.;Jo, H.C.;Choi, Y.S.;Kim, S.H.;Sim, K.D.;Sohn, M.H.
    • Progress in Superconductivity and Cryogenics
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    • v.17 no.1
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    • pp.28-31
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    • 2015
  • An in-flight fragment separator, which aims to produce and study rare isotopes, consists of superferric quadrupole triplets and $30^{\circ}$ dipole magnets to focus and bend the beams for achromatic focusing and momentum dispersion, respectively. The separator is divided into pre and main stages, and we plan to use superconducting magnets employing high-Tc superconductor (HTS) coils in the pre-separator area, where radiation heating is high. The HTS coils will be cooled by cold He gas in 20-50 K, and in the other area, superferric magnets using low-temperature superconductor (LTS) will be used at 4 K. A few LTS coils were wound and successfully tested in a LHe dewar, and the design of cryostat has been optimized. Development of the HTS coils is ongoing in collaboration with a group at KERI. An HTS coil of racetrack shape was wound and tested in a $LN_2$ bath and in a dewar with cryocooler. No degradation on critical current due to coil winding was found.

Analysis on Wireless Communications Environment at Lunar Surface for Lunar Exploration (달 탐사를 위한 달 표면에서의 무선통신 환경 분석)

  • Lee, Yong-Min;Lee, Byong-Sun;Ahn, Jae-Young
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.10
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    • pp.50-54
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    • 2014
  • Evaluation of the possible or probable effects of environmental conditions which are temperature, radiation, dust as well as other possibilities in terms of meteoroids, seismicity, and no global magnetic field has been carried out for wireless communications on the lunar surface in this paper. The results considered in this paper can be utilized as a basic information on making efficient use of the design for wireless communications system in Korean lunar exploration project.