• Title/Summary/Keyword: Radiation level

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Delayed radiation-induced inflammation accompanying a marked carbohydrate antigen 19-9 elevation in a patient with resected pancreatic cancer

  • Mattes, Malcolm D.;Cardinal, Jon S.;Jacobson, Geraldine M.
    • Radiation Oncology Journal
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    • v.34 no.2
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    • pp.156-159
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    • 2016
  • Although carbohydrate antigen (CA) 19-9 is a useful tumor marker for pancreatic cancer, it can also become elevated from a variety of benign and malignant conditions. Herein we describe an unusual presentation of elevated CA 19-9 in an asymptomatic patient who had previously undergone adjuvant chemotherapy and radiation therapy for resected early stage pancreatic cancer. The rise in CA 19-9 might be due to delayed radiation-induced inflammation related to previous intra-abdominal radiation therapy with or without radiation recall induced by gemcitabine. After treatment with corticosteroids the CA 19-9 level decreased to normal, and the patient has not developed any evidence of recurrent cancer to date.

Characteristics of the Graded Wildlife Dose Assessment Code K-BIOTA and Its Application (단계적 야생동식물 선량평가 코드 K-BIOTA의 특성 및 적용)

  • Keum, Dong-Kwon;Jun, In;Lim, Kwang-Muk;Kim, Byeong-Ho;Choi, Yong-Ho
    • Journal of Radiation Protection and Research
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    • v.40 no.4
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    • pp.252-260
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    • 2015
  • This paper describes the technical background for the Korean wildlife radiation dose assessment code, K-BIOTA, and the summary of its application. The K-BIOTA applies the graded approaches of 3 levels including the screening assessment (Level 1 & 2), and the detailed assessment based on the site specific data (Level 3). The screening level assessment is a preliminary step to determine whether the detailed assessment is needed, and calculates the dose rate for the grouped organisms, rather than an individual biota. In the Level 1 assessment, the risk quotient (RQ) is calculated by comparing the actual media concentration with the environmental media concentration limit (EMCL) derived from a bench-mark screening reference dose rate. If RQ for the Level 1 assessment is less than 1, it can be determined that the ecosystem would maintain its integrity, and the assessment is terminated. If the RQ is greater than 1, the Level 2 assessment, which calculates RQ using the average value of the concentration ratio (CR) and equilibrium distribution coefficient (Kd) for the grouped organisms, is carried out for the more realistic assessment. Thus, the Level 2 assessment is less conservative than the Level 1 assessment. If RQ for the Level 2 assessment is less than 1, it can be determined that the ecosystem would maintain its integrity, and the assessment is terminated. If the RQ is greater than 1, the Level 3 assessment is performed for the detailed assessment. In the Level 3 assessment, the radiation dose for the representative organism of a site is calculated by using the site specific data of occupancy factor, CR and Kd. In addition, the K-BIOTA allows the uncertainty analysis of the dose rate on CR, Kd and environmental medium concentration among input parameters optionally in the Level 3 assessment. The four probability density functions of normal, lognormal, uniform and exponential distribution can be applied.The applicability of the code was tested through the participation of IAEA EMRAS II (Environmental Modeling for Radiation Safety) for the comparison study of environmental models comparison, and as the result, it was proved that the K-BIOTA would be very useful to assess the radiation risk of the wildlife living in the various contaminated environment.

구조 변경 기법을 이용한 로타리 컴프레서의 방사소음특성 분석 및 소음저감

  • 박상영;이상현;이수일;이승갑;박윤서
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1995.10a
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    • pp.778-781
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    • 1995
  • In this paper, sound radiation of a rotary compressor used in room air-conditioner is investigated. structural eigenmodes are identified through modal test. Since accumulator is found important factor of sound radiation, damping material was added around accumulator to reduce sound radiation level of rotary compressor. As result, sound radiation was reduced to 3 dB.

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The Variation of Silicon Characteristic with Radiation Damage Effects (Radiation 손상에 기인한 실리콘 특성변화)

  • 장기현
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.15 no.4
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    • pp.26-32
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    • 1978
  • For a long life photovoltaic cell the degradation of the device characteristics with 1 MeV electron radiation must be known so as to be able to predict the life of the cell. Hence, a study was made of radiation damage effects on the bulk properties of the silicon crystal. From the results of the data, it is concluded that there appeared to be a steads rotate damage level reached in f type material.

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Proposing a Simple Radiation Scale for the Public: Radiation Index

  • Cho, Gyuseong;Kim, Jong Hyun;Park, Tae Soon;Cho, Kunwoo
    • Nuclear Engineering and Technology
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    • v.49 no.3
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    • pp.598-608
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    • 2017
  • A new radiation scale is proposed. With empathy toward the vast majority of people who are not well versed in radiation and related matters, and thus suffering from misunderstanding that breeds unnecessary fear of radiation, the aim of proposing a new radiation scale, radiation index (RAIN), is to put the general public at ease with the concept of radiation. RAIN is defined in dimensionless numbers that relate any specific radiation dose to a properly defined reference level. As RAIN is expressed in plain numbers without an attached scientific unit, the public will feel comfortable with its friendly look, which in turn should help them understand radiation dose levels easily and allay their anxieties about radiation. The expanded awareness and proper understanding of radiation will empower the public to feel that they are not hopeless victims of radiation. The correspondence between RAIN and the specific accumulated dose is established. The equivalence will allow RAIN to serve as a common language of communication for the general public with which they can converse with radiation experts to discuss matters related to radiation safety, radiation diagnosis and therapy, nuclear accidents, and other related matters. Such fruitful dialogues will ultimately enhance public acceptance of radiation and associated technologies.

Exposure of the Population in the United States to Ionizing Radiation

  • Carter Melvin W.;Oliver Robert W.
    • Journal of Radiation Protection and Research
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    • v.12 no.2
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    • pp.37-50
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    • 1987
  • The exposure of the population in the United States to ionizing radiation has recently been evaluated by the National Council on Radiation Protection and Measurements (NCRP). This was done by constituting six organizational groups to address various phases of the work and the results of this work are summarized in this article. The article is based on the report, by the same title, which is scheduled for publication by the NCRP in September, 1987. The six organizational groups are titled Radiation Exposure from Consumer Products, Natural Background Radiation, Radiation Associated with Medical Examinations, Radiation Received by Radiation Employees, Public Exposure from Nuclear Power, and Exposure from Miscellaneous Environmental Sources. These titles are descriptive of the subject areas covered by each of these separate groups. The data evaluated are for the years 1977-1984 with the majority of the data being for the period 1980-1982. Summary information is presented and discussed for the number of people exposed to given sources, the effective dose equivalent, the average effective dose equivalent to the U.S. population, and the genetically significant dose equivalent. The average annual effective dose equivalent from all sources to the U.S. population is approximately 3.6 mSv (360 mrem). Exposures to natural sources make the largest contribution to this total. Radon and radon decay products contribute 2.0 mSv (200 mrem) whereas the other naturally occurring radionuclides contribute 1.0 mSv (100 mrem). Among man-made or enhanced sources, medical exposures make the largest additional contributions, namely 0.39 mSv (39 mrem) for diagnosis and 0.14 mSv (14 mrem) for nuclear medicine. It was not possible to evaluate exposures for therapy. Most of the other sources of population exposure, including nuclear power and consumer products, are minor. A possible exception would be the use of tobacco products. These exposures are discussed in relation to a negligible individual risk level of $10{\mu}Sv/y$ (1 mrem/y). The NCRP considers exposures below the negligible individual risk level as trivial and as such should be dismissed.

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Significant fibrosis after radiation therapy in a patient with Marfan syndrome

  • Suarez, Eva M.;Knackstedt, Rebecca J.;Jenrette, Joseph M.
    • Radiation Oncology Journal
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    • v.32 no.3
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    • pp.208-212
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    • 2014
  • Marfan syndrome is one of the collagen vascular diseases that theoretically predisposes patients to excessive radiation-induced fibrosis yet there is minimal published literature regarding this clinical scenario. We present a patient with a history of Marfan syndrome requiring radiation for a diagnosis of a right brachial plexus malignant nerve sheath tumor. It has been suggested that plasma transforming growth factor beta 1 (TGF-${\beta}1$) can be monitored as a predictor of subsequent fibrosis in this population of high risk patients. We therefore monitored the patient's TGF-${\beta}1$ level during and after treatment. Despite maintaining stable levels of plasma TGF-${\beta}1$, our patient still developed extensive fibrosis resulting in impaired range of motion. Our case reports presents a review of the literature of patients with Marfan syndrome requiring radiation therapy and the limitations of serum markers on predicting long-term toxicity.

Comparing with self-efficacy and knowledge, attitudes about radiation safety management of dental hygienists and students at department of dental hygiene (치과위생사와 치위생과 학생의 자기효능감과 방사선안전관리 지식 및 태도에 대한 비교)

  • Yoon, Jung-Ae;Yoon, Young-Sook
    • Journal of Korean society of Dental Hygiene
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    • v.11 no.5
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    • pp.729-739
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    • 2011
  • Objectives : It is important to catch individual characteristics by measuring the level of self-efficacy, radiation safety knowledge, attitudes to increase behavior levels in the radiation safety management(RSM) and we consider this should be applied to the professional program development to improve RSM activities of dental hygienist and students at department of dental hygiene. Methods : This study mentioned mainly self-efficacy, radiation safety knowledge, attitudes for dental hygienists and the second & third year students at department of dental hygiene in Pusan area to provide the correct information associated with the use of radiation and to be aid in the development program to increase behavior levels in the RSM in dental care institutions and schools in the future and performed a survey 8 May to 7 Juiy, 2011. The survey results were as follows Results : 1. The results of self-efficacy is $3.53{\pm}0.42$ points for the dental hygienist and $3.32{\pm}0.40$ points for students(p<0.001). 2. According to the knowledge level of RSM, the result is $11.7{\pm}3.12$ points for the dental hygienist and $9.56{\pm}2.72$ points for students(p<0.001). 3. According to the knowledge level of RSM, the result is $4.40{\pm}0.49$ points for the dental hygienist and $4.22{\pm}0.56$ points for students(p<0.001). 4. According to relationship among self-efficacy, radiation safety knowledge and attitudes, the higher the score for knowledge of RSM was, the higher the score for self-efficacy was. The higher the score for attitudes was, the higher the score for self-efficacy and knowledge was(p<0.01). 5. The factors to affect attitudes about RSM were self-efficacy, knowledge(p<0.01).

Radial displacement of clinical target volume in node negative head and neck cancer

  • Jeon, Wan;Wu, Hong-Gyun;Song, Sang-Hyuk;Kim, Jung-In
    • Radiation Oncology Journal
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    • v.30 no.1
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    • pp.36-42
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    • 2012
  • Purpose: To evaluate the radial displacement of clinical target volume in the patients with node negative head and neck (H&N) cancer and to quantify the relative positional changes compared to that of normal healthy volunteers. Materials and Methods: Three node-negative H&N cancer patients and five healthy volunteers were enrolled in this study. For setup accuracy, neck thermoplastic masks and laser alignment were used in each of the acquired computed tomography (CT) images. Both groups had total three sequential CT images in every two weeks. The lymph node (LN) level of the neck was delineated based on the Radiation Therapy Oncology Group (RTOG) consensus guideline by one physician. We use the second cervical vertebra body as a reference point to match each CT image set. Each of the sequential CT images and delineated neck LN levels were fused with the primary image, then maximal radial displacement was measured at 1.5 cm intervals from skull base (SB) to caudal margin of LN level V, and the volume differences at each node level were quantified. Results: The mean radial displacements were 2.26 (${\pm}1.03$) mm in the control group and 3.05 (${\pm}1.97$) in the H&N cancer patients. There was a statistically significant difference between the groups in terms of the mean radial displacement (p = 0.03). In addition, the mean radial displacement increased with the distance from SB. As for the mean volume differences, there was no statistical significance between the two groups. Conclusion: This study suggests that a more generous radial margin should be applied to the lower part of the neck LN for better clinical target coverage and dose delivery.

Neutron Dosimetry and Monitoring in the Radiation Environment

  • Nakamura, Takashi
    • Journal of Radiation Protection and Research
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    • v.14 no.2
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    • pp.51-62
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    • 1989
  • The high efficiency moderated-type neutron spectrometer and doseequivalent counter were developed for the measurement of low level environmental neutrons. By using these detectors, the neutron energy spectra and dose equivalent rates due to skyshine effect were measured in the environment surrounding the accelerator facilities and also the altitude variation of cosmic ray neutrons in the aircraft flying over Japan.

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