Experimental evaluation of radiator control based on primary supply temperature for district heating substations

International Nuclear Information System (INIS)

Gustafsson, Jonas; Delsing, Jerker; Deventer, Jan van

2011-01-01

Highlights: → We compared a new radiator system control approach with traditional control. → This is an experimental verification of previous simulation results. → We examine changes in delta-T and indoor comfort. → The indoor comfort were not affected by the introduction of alt. radiator control. → The alternative control method can contribute to an increased delta-T. -- Abstract: In this paper, we evaluate whether the primary supply temperature in district heating networks can be used to control radiator systems in buildings connected to district heating; with the purpose of increasing the ΔT. The primary supply temperature in district heating systems can mostly be described as a function of outdoor temperature; similarly, the radiator supply temperature in houses, offices and industries can also be described as a function of outdoor temperature. To calibrate the radiator control system to produce an ideally optimal radiator supply temperature that produces a maximized ΔT across the substation, the relationship between the primary supply temperature and outdoor temperature must be known. However, even if the relation is known there is always a deviation between the expected primary supply temperature and the actual temperature of the received distribution media. This deviation makes the radiator control system incapable of controlling the radiator supply temperature to a point that would generate a maximized ΔT. Published simulation results show that it is possible and advantageous to utilize the primary supply temperature for radiator system control. In this paper, the simulation results are experimentally verified through implementation of the control method in a real district heating substation. The primary supply temperature is measured by the heat-meter and is shared with the radiator control system; thus no additional temperature sensors were needed to perform the experiments. However additional meters were installed for surveillance purposes

Radiation exposure in the young level 1 trauma patient: a retrospective review.

Science.gov (United States)

Gottschalk, Michael B; Bellaire, Laura L; Moore, Thomas

2015-01-01

Computed tomography (CT) has become an increasingly popular and powerful tool for clinicians managing trauma patients with life-threatening injuries, but the ramifications of increasing radiation burden on individual patients are not insignificant. This study examines a continuous series of 337 patients less than 40 years old admitted to a level 1 trauma center during a 4-month period. Primary outcome measures included number of scans; effective dose of radiation from radiographs and CT scans, respectively; and total effective dose from both sources over patients' hospital stays. Several variables, including hospital length of stay, initial Glasgow Coma Scale score, and Injury Severity Score, correlated with greater radiation exposure. Blunt trauma victims were more prone to higher doses than those with penetrating or combined penetrating and blunt trauma. Location and mechanism of injury were also found to correlate with radiation exposure. Trauma patients as a group are exposed to high levels of radiation from X-rays and CT scans, and CT scans contribute a very high proportion (91.3% ± 11.7%) of that radiation. Certain subgroups of patients are at a particularly high risk of exposure, and greater attention to cumulative radiation dose should be paid to patients with the above mentioned risk factors.

Understanding radiation and risk: the importance of primary and secondary education

International Nuclear Information System (INIS)

Tada, Junichiro

1999-01-01

In Japan's primary and secondary schools, radiation and radioactivity are taught as part of the curriculum dealing with social science subjects. Students learn much about the hazardous features of radiation, but lack the scientific understanding necessary to build a more balanced picture. Although the same point applies to education covering the harmful effects of volcanic eruptions, earthquakes, electrical storms and so on, public understanding of these events is relatively high and students are generally able to make informed judgments about the risks involved. By contrast, their limited understanding of radiation often contributes to fears that it is evil or even supernatural. To correct this distortion, it is important that primary and secondary education includes a scientific explanation of radiation. Like heat and light, radiation is fundamental to the history of the universe; and scientific education programs should give appropriate emphasis to this important subject. Students would then be able to make more objective judgments about the useful and hazardous aspects of radiation. (author)

Understanding radiation and risk: the importance of primary and secondary education

Energy Technology Data Exchange (ETDEWEB)

Tada, Junichiro [Japan Synchrotron Radiation Research Institute (SPring-8), Mikaduki, Hyogo (Japan)

1999-09-01

In Japan's primary and secondary schools, radiation and radioactivity are taught as part of the curriculum dealing with social science subjects. Students learn much about the hazardous features of radiation, but lack the scientific understanding necessary to build a more balanced picture. Although the same point applies to education covering the harmful effects of volcanic eruptions, earthquakes, electrical storms and so on, public understanding of these events is relatively high and students are generally able to make informed judgments about the risks involved. By contrast, their limited understanding of radiation often contributes to fears that it is evil or even supernatural. To correct this distortion, it is important that primary and secondary education includes a scientific explanation of radiation. Like heat and light, radiation is fundamental to the history of the universe; and scientific education programs should give appropriate emphasis to this important subject. Students would then be able to make more objective judgments about the useful and hazardous aspects of radiation. (author)

PWR type reactor equipped with a primary circuit loop water level gauge

International Nuclear Information System (INIS)

Suzuki, Mitsuhiro.

1990-01-01

The time of lowering a water level to less than the position of high temperature side pipeway nozzle has been rather delayed because of the swelling of mixed water level due to heat generation of the reactor core. Further, there has been a certain restriction for the installation, maintenance and adjustment of a water level gauge since it is at a position under high radiation exposure. Then, a differential pressure type water level gauge with temperature compensation is disposed at a portion below a water level gauge of a pressurizer and between the steam generator exit plenum and the lower end of the loop seal. Further, a similar water level system is disposed to all of the loops of the primary circulation circuits. In a case that the amount of water contained in a reactor container should decreased upon occurrence of loss of coolant accidents caused by small rupture and stoppage of primary circuit pumps, lowering of the water level preceding to the lowering of the water level in the reactor core is detected to ensure the amount of water. Since they are disposed to all of the loops and ensure the excess margin, reliability for the detection of the amount of contained water can be improved by averaging time for the data of the water level and averaging the entire systems, even when there are vibrations in the fluid or pressure in the primary circuit. (N.H.)

Primary ovarian leiomyosarcoma in an adolescent following radiation for medulloblastoma

International Nuclear Information System (INIS)

O'Sullivan, S.G.; Das Narla, L.; Ferraro, E.

1998-01-01

Primary ovarian leiomyosarcomas are rare neoplasms of the ovary, particularly in the pediatric population. Their occurrence following radiation therapy for previous malignancy has important implications. We present a case of primary ovarian leiomyosarcoma in an adolescent following therapy for medulloblastoma. (orig.)

Acceptance criteria for deposition of low-level and intermediate-level radiation levels radioactive wastes

International Nuclear Information System (INIS)

2002-09-01

This norm establishes the criteria for acceptance low and intermediate radiation level for safe deposition in repositories, for assuring the protection of workers, population and environment against the hazardous effects of the ionizing radiations. The criteria of this norm applies to the low and intermediate radiation levels

Coronary cineangiography and ionizing radiation exposure to patients: analysis of primary and secondary beam

International Nuclear Information System (INIS)

Ramirez, Alfredo; Leyton, Fernando; Silva, Ana Maria; Farias, Eric

2001-01-01

The purpose of this work was to determine the level of exposure dose to patients during coronariographies in different areas of body. This study has presented the medical surveillance of 18 cases and the radiation monitoring of these patients by TLD in thyroid and pelvis (secondary beam) and, in the right and left scapular region (primary beam) for each one of these procedures. The ionizing radiation received was 215 ± 200 mGy in left scapular region (range 1-710) and 255±213 mGy in the right scapular region (range 22-635) p=NS. In the pelvic region the ionizing radiation was 0,22±0,06 mGy and in the thyroid region was 3,62±2,44 mGy

Radiation therapy in recurrence of carcinoma of the uterine cervix after primary surgery

International Nuclear Information System (INIS)

Kim, Jin Hee; Kim, Ok Bae

2003-01-01

The purpose of this study was to evaluate treatment results in terms of the survival and failure patterns subsequent to radiation therapy in recurrent cervical cancer, following primary surgery. Between January 1990 and December 1999, 27 patients, with recurrent cervical cancer following primary surgery, were subsequently treated with radiation in the Department of Radiation Oncology, at the Keimyung University Dongsan Medical Center. Their median age was 48, ranging from 31 to 70 years old. With regard to the initial FIGO stage on presentation, 20 and 7 patients were stages I and II, respectively. Twenty three patients had squamous ceH carcinomas and 4 had adenocarcinomas. The time interval from the primary surgery to the recurrence ranged from 2 to 90 months with a median of 29 months. The recurrent sites were the vaginal cuff alone, the pelvic cavity and combined recurrence in 14, 9 and 4 patients, respectively. Radiation was performed, with external and vaginal intracavitary radiation in 13 patients, external radiation alone in 13 and vaginal intracavitary radiation alone in another one. The median follow-up period was 55 months, ranging from 6 to 128 months. The five year disease free survival (5y DFS) and five year overall survival (5y OS) rates were 68.2 and 71.9%, respectively. There was a marginal statistically significant difference in the 5y DFS in relation to the recurrent site (5y DFS, 85.7% in vaginal cuff recurrence alone, 53.3% in pelvic cavity recurrence, p=0.09). There was no difference in the survival according to the time interval between the primary surgery and a recurrence. There was only a 7% local failure rate in the patients with a vaginal cuff recurrence. The major failure patterns were local failure in the patients with pelvic cavity recurrence, and distant failure in the patients with a combined recurrence. There were no complications above grade 3 after the radiation therapy. Radiation therapy was safe and effective treatment for a

Imaging Primary Lung Cancers in Mice to Study Radiation Biology

International Nuclear Information System (INIS)

Kirsch, David G.; Grimm, Jan; Guimaraes, Alexander R.; Wojtkiewicz, Gregory R.; Perez, Bradford A.; Santiago, Philip M.; Anthony, Nikolas K.; Forbes, Thomas; Doppke, Karen

2010-01-01

Purpose: To image a genetically engineered mouse model of non-small-cell lung cancer with micro-computed tomography (micro-CT) to measure tumor response to radiation therapy. Methods and Materials: The Cre-loxP system was used to generate primary lung cancers in mice with mutation in K-ras alone or in combination with p53 mutation. Mice were serially imaged by micro-CT, and tumor volumes were determined. A comparison of tumor volume by micro-CT and tumor histology was performed. Tumor response to radiation therapy (15.5 Gy) was assessed with micro-CT. Results: The tumor volume measured with free-breathing micro-CT scans was greater than the volume calculated by histology. Nevertheless, this imaging approach demonstrated that lung cancers with mutant p53 grew more rapidly than lung tumors with wild-type p53 and also showed that radiation therapy increased the doubling time of p53 mutant lung cancers fivefold. Conclusions: Micro-CT is an effective tool to noninvasively measure the growth of primary lung cancers in genetically engineered mice and assess tumor response to radiation therapy. This imaging approach will be useful to study the radiation biology of lung cancer.

Proposal to integrate the service on radiation hygiene at the primary health care services for workers exposed to ionizing radiation

International Nuclear Information System (INIS)

Frometa Suarez, Ileana; Lopez Pumar, Georgina; Gonzalez Amil, Melva

1998-01-01

The National Health System implemented in the last few years a new pattern of primary attention for workers by creating doctors offices in work centers. At the same time, the Ministry of Public Health (MINSAP) carries the medical surveillance of the staff exposed to ionizing radiation. This work proposes a program to integrate the consulting room on radiation hygiene to primary health care services for workers that work with ionizing radiation sources, aiming to ameliorate and improve them

SGR-76 gamma radiation level indicator

International Nuclear Information System (INIS)

Chubinskij-Nadezhdin, I.V.

1978-01-01

The design of a gamma-radiation level indicator is described; the instrument is part of a mobile radiometric laboratory (MRL). The design of the instrument permits gamma-radiation dose rates recording at 0.2-200 R/hr, and signals on gamma-background levels. The instrument has two separate threshold levels of signalling actuation. The light signalling at the first level is precautionary, and the sound signalling at the second level indicates the necessity of taking a decision as to whether or not the MRL can remain in the gamma-radiation field. Halogenic counters operating in a current mode are used as detectors. The basic error in recording the dose rate amounts to +-25%. Overall dimensions of the instrument 150x280x100 mm; weight less than 2.5 kg

Primary cosmic radiation

International Nuclear Information System (INIS)

Anderson, H.R.

1972-01-01

The term cosmic radiation means the charged particle flux that reaches the earth from outside its magnetosphere with energies above the solar wind energy of a few keV. There are two sources of flux. Sporadically the sun produces such particles, generally within the energy range 1--200 MeV, and these solar cosmic rays arrive at the earth for a period ranging from hours to days. There may be a small, rather constant flux from the sun also, but the bulk of the steady flux originates outside the earth's orbit. Although some have conjectured that part of this latter flux may be accelerated in the outer portions of the solar system where the outward flowing interplanetary medium meets the interstellar medium, it is generally thought that most or all of it arises in unique systems such as supernovae, and is distributed throughout the galaxy. These galactic particles range in energy from a few MeV to at least 10 13 MeV and consist primarily of protons with significant numbers of heavier nuclei, positrons and electrons. They are supposed to fill our galaxy, or at least the disc, more or less uniformly. However, the flux with energies below a few GeV that reaches earth's orbit is modulated by the interplanetary medium so that the number at earth varies inversely with solar activity and is always somewhat below the interstellar flux. A discussion is presented of primary galactic radiation at earth, its modulation by solar activity, and its interaction with the geomagnetic field. (U.S.)

Can low-level radiation cause cancer?

International Nuclear Information System (INIS)

Trosko, J.E.

1995-01-01

Health in a multicellular organism is maintained by homeostatic processes. Disruption of these homeostatic controls at the molecular, biochemical, cellular, and organ systems levels can be brought about by irreversible changes in the genetic material (mutagenesis), cell death (cytotoxicity), or reversible changes in the expression of genes at the transcriptional, translational, or posttranslational levels (epigenesis). While radiation is known to induce DNA damage/mutations, cell, death and epigenetic changes, in addition to cancers that are found in radiation-exposed animals, experimentally, and in humans, epidemiologically, the question is, At low-level exposure, what is the risk that cancers are open-quotes causedclose quotes by the radiation?

Radiation therapy for primary orbital lymphoma

International Nuclear Information System (INIS)

Chao, Cliff K.S.; Lin Hsiusan; Rao Devineni, V.; Smith, Morton

1995-01-01

Purpose: The influence of tumor size, grade, thoroughness of staging workup, and radiation dose on disease control, radiation-related complications, and incidence of systemic progression of primary orbital lymphoma is analyzed. Methods and Materials: Twenty patients with Stage I primary orbital lymphoma were treated from August 1976 through August 1991 at Mallinckrodt Institute of Radiology. Staging workups included physical examination, chest x-ray, complete blood count (CBC), liver function test, and computerized tomography (CT) scan of the orbit, abdomen, and pelvis. Nineteen patients had bone marrow biopsy. The histological types based on the National Cancer Institute working formulation were 9 low-grade and 11 intermediate-grade, including five lymphocytic lymphomas of intermediate differentiation. The extension of disease and the volume of tumor were evaluated by CT scan of the orbit. The most commonly used radiation therapy technique was single anterior direct field with 4 MV or 6 MV photons. Lens was shielded or not treated in eight patients. Dose ranged from 20 to 43.2 Gy. Thirteen of 20 patients received 30 Gy. Minimum follow-up was 24 months (median, 4 years). Results: Local control was achieved in all 20 patients. One patient with lymphocytic lymphoma with intermediate differentiation developed disseminated disease. Actuarial disease-free survival (DFS) was 100% and 90% at 2 and 5 years, respectively. No retinopathy was observed. Cataracts were noted in seven patients at 1 to 10 years following irradiation (median, 2 years). Three patients developed lacrimal function disorder, however, no corneal ulceration occurred. Conclusions: Thirty Gy in 15 fractions appears to be a sufficient dose for local control with acceptable morbidity, especially for low-grade, as well as certain types of intermediate-grade lymphomas, such as diffuse small cleaved cell and lymphocytic lymphoma of intermediate differentiation. Systemic dissemination is minimal, provided local

Radiation therapy for primary orbital lymphoma

Energy Technology Data Exchange (ETDEWEB)

Chao, Cliff K.S.; Hsiusan, Lin; Rao Devineni, V; Smith, Morton

1995-02-15

Purpose: The influence of tumor size, grade, thoroughness of staging workup, and radiation dose on disease control, radiation-related complications, and incidence of systemic progression of primary orbital lymphoma is analyzed. Methods and Materials: Twenty patients with Stage I primary orbital lymphoma were treated from August 1976 through August 1991 at Mallinckrodt Institute of Radiology. Staging workups included physical examination, chest x-ray, complete blood count (CBC), liver function test, and computerized tomography (CT) scan of the orbit, abdomen, and pelvis. Nineteen patients had bone marrow biopsy. The histological types based on the National Cancer Institute working formulation were 9 low-grade and 11 intermediate-grade, including five lymphocytic lymphomas of intermediate differentiation. The extension of disease and the volume of tumor were evaluated by CT scan of the orbit. The most commonly used radiation therapy technique was single anterior direct field with 4 MV or 6 MV photons. Lens was shielded or not treated in eight patients. Dose ranged from 20 to 43.2 Gy. Thirteen of 20 patients received 30 Gy. Minimum follow-up was 24 months (median, 4 years). Results: Local control was achieved in all 20 patients. One patient with lymphocytic lymphoma with intermediate differentiation developed disseminated disease. Actuarial disease-free survival (DFS) was 100% and 90% at 2 and 5 years, respectively. No retinopathy was observed. Cataracts were noted in seven patients at 1 to 10 years following irradiation (median, 2 years). Three patients developed lacrimal function disorder, however, no corneal ulceration occurred. Conclusions: Thirty Gy in 15 fractions appears to be a sufficient dose for local control with acceptable morbidity, especially for low-grade, as well as certain types of intermediate-grade lymphomas, such as diffuse small cleaved cell and lymphocytic lymphoma of intermediate differentiation. Systemic dissemination is minimal, provided local

Course of radiation protection: technical level

International Nuclear Information System (INIS)

2002-01-01

The course handbook on radiation protection and nuclear safety, technical level prepared by scientists of the Nuclear Regulatory Authority (ARN) of the Argentina Republic, describes the subjects in 19 chapters and 2 annexes. These topics detailed in the text have the following aspects: radioactivity elements, interaction of the radiation and the matter, radio dosimetry, internal contamination dosimetry, principles of radiation detection, biological radiation effects, fundamentals of radiation protection, dose limits, optimization, occupational exposure, radiation shielding, radioactive waste management, criticality accidents, safe transport of radioactive materials, regulatory aspects

Radiation Therapy for Primary Cutaneous Anaplastic Large Cell Lymphoma: An International Lymphoma Radiation Oncology Group Multi-institutional Experience

Energy Technology Data Exchange (ETDEWEB)

Million, Lynn, E-mail: lmillion@stanford.edu [Stanford Cancer Institute, Stanford, California (United States); Yi, Esther J.; Wu, Frank; Von Eyben, Rie [Stanford Cancer Institute, Stanford, California (United States); Campbell, Belinda A. [Department of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, East Melbourne (Australia); Dabaja, Bouthaina [The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Tsang, Richard W. [Department of Radiation Oncology, Princess Margaret Cancer Centre, Toronto, Ontario (Canada); Ng, Andrea [Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Wilson, Lynn D. [Department of Therapeutic Radiology/Radiation Oncology, Yale School of Medicine, Yale Cancer Center, New Haven, Connecticut (United States); Ricardi, Umberto [Department of Oncology, University of Turin, Turin (Italy); Kirova, Youlia [Institut Curie, Paris (France); Hoppe, Richard T. [Stanford Cancer Institute, Stanford, California (United States)

2016-08-01

Purpose: To collect response rates of primary cutaneous anaplastic large cell lymphoma, a rare cutaneous T-cell lymphoma, to radiation therapy (RT), and to determine potential prognostic factors predictive of outcome. Methods and Materials: The study was a retrospective analysis of patients with primary cutaneous anaplastic large cell lymphoma who received RT as primary therapy or after surgical excision. Data collected include initial stage of disease, RT modality (electron/photon), total dose, fractionation, response to treatment, and local recurrence. Radiation therapy was delivered at 8 participating International Lymphoma Radiation Oncology Group institutions worldwide. Results: Fifty-six patients met the eligibility criteria, and 63 tumors were treated: head and neck (27%), trunk (14%), upper extremities (27%), and lower extremities (32%). Median tumor size was 2.25 cm (range, 0.6-12 cm). T classification included T1, 40 patients (71%); T2, 12 patients (21%); and T3, 4 patients (7%). The median radiation dose was 35 Gy (range, 6-45 Gy). Complete clinical response (CCR) was achieved in 60 of 63 tumors (95%) and partial response in 3 tumors (5%). After CCR, 1 tumor recurred locally (1.7%) after 36 Gy and 7 months after RT. This was the only patient to die of disease. Conclusions: Primary cutaneous anaplastic large cell lymphoma is a rare, indolent cutaneous lymphoma with a low death rate. This analysis, which was restricted to patients selected for treatment with radiation, indicates that achieving CCR was independent of radiation dose. Because there were too few failures (<2%) for statistical analysis on dose response, 30 Gy seems to be adequate for local control, and even lower doses may suffice.

Second primary tumor and radiation induced neoplasma in the uterine cancer

International Nuclear Information System (INIS)

Sakurai, Tomoyasu; Nishio, Masamichi; Kagami, Yoshikazu; Murakami, Yoshitaka; Narimatsu, Naoto; Kanemoto, Toshitaka

1984-01-01

This report is concerned with multiple primary cancers developing in invasive uterine cancer. Second primary tumors were recorded 27 women with a total of 30 non-uterine cancer (exception of radiation-induced cancer). 17 patients of radiation-induced neoplasm were observed (Rectal cancer 4, soft part sarcoma 4, cancer of urinary bladder 3, bone tumor 3, uterin cancer 2 and cancer of Vulva 1). One case is 4 legions (corpus, sigma, thymoma and stomach), 2 cases are 3 lesions (uterine cervix, stomach and maxillay siuis: uterine cervix, thyroidal gland and radiation-induced soft part sarcoma). Only 5 of these 17 patients were known irradiated dose (50 Gy--55 Gy), however others unknown. The mean latent periods of 17 cases of radiation induced neoplasms are 19.4 years. 16 patients of late second cancers of the cervix appearing from 11 to 36 years (average 19.5 years) after initial radiotherapy were recorded. (author)

Low level radiation: biological effects

International Nuclear Information System (INIS)

Loken, M.K.

1983-01-01

It is imperative that physicians and scientists using radiations in health care delivery continue to assess the benefits derived, vs. potential risk, to patients and radiation workers being exposed to radiation in its various forms as part of our health delivery system. Insofar as possible we should assure our patients and ourselves that the benefits outweigh the potential hazards involved. Inferences as to the possible biological effects of low level radiation are generally based on extrapolations from those effects observed and measured following acute exposures to considerably higher doses of radiation. Thus, in order to shed light on the question of the possible biological effects of low level radiation, a wide variety of studies have been carried out using cells in culture and various species of plant and animal life. This manuscript makes reference to some of those studies with indications as to how and why the studies were done and the conclusions that might be drawn there from. In addition reference is made to the handling of this information by scientists, by environmentalists, and by the news media. Unfortunately, in many instances the public has been misled by what has been said and/or written. It is hoped that this presentation will provide an understandable and reasonable perspective on the various appropriate uses of radiation in our lives and how such uses do provide significant improvement in our health and in our quality of life

Background radiation levels and standards for protection from ionizing radiations

International Nuclear Information System (INIS)

Farai, I.

1999-01-01

Apart from the amount of radiation which a worker may receive while he performs his work, he is also exposed to radiation because of the nature of his environment. In other words, all individuals are subject to some irradiation even though they may not work with radioactive substances. This source of radiation exposure is often referred to as background radiation. In most environments, it is low-level and can be grouped into two natural and man-made. Background radiation provides the basis on which allowable exposure limits for workers are drawn

Differential Gene Expression in Primary Human Skin Keratinocytes and Fibroblasts in Response to Ionizing Radiation

Science.gov (United States)

Warters, Raymond L.; Packard, Ann T.; Kramer, Gwen F.; Gaffney, David K.; Moos, Philip J.

2009-01-01

Although skin is usually exposed during human exposures to ionizing radiation, there have been no thorough examinations of the transcriptional response of skin fibroblasts and keratinocytes to radiation. The transcriptional response of quiescent primary fibroblasts and keratinocytes exposed to from 10 cGy to 5 Gy and collected 4 h after treatment was examined. RNA was isolated and examined by microarray analysis for changes in the levels of gene expression. Exposure to ionizing radiation altered the expression of 279 genes across both cell types. Changes in RNA expression could be arranged into three main categories: (1) changes in keratinocytes but not in fibroblasts, (2) changes in fibroblasts but not in keratinocytes, and (3) changes in both. All of these changes were primarily of p53 target genes. Similar radiation-induced changes were induced in immortalized fibroblasts or keratinocytes. In separate experiments, protein was collected and analyzed by Western blotting for expression of proteins observed in microarray experiments to be overexpressed at the mRNA level. Both Q-PCR and Western blot analysis experiments validated these transcription changes. Our results are consistent with changes in the expression of p53 target genes as indicating the magnitude of cell responses to ionizing radiation. PMID:19580510

Radiation Protection Aspects of Primary Water Chemistry and Source-term Management Report

International Nuclear Information System (INIS)

2014-04-01

Since the beginning of the 1990's, occupational exposures in nuclear power plant has strongly decreased, outlining efforts achieved by worldwide nuclear operators in order to reach and maintain occupational exposure as low as reasonably achievable (ALARA) in accordance with international recommendations and national regulations. These efforts have focused on both technical and organisational aspects. According to many radiation protection experts, one of the key features to reach this goal is the management of the primary system water chemistry and the ability to avoid dissemination of radioactivity within the system. It outlines the importance for radiation protection staff to work closely with chemistry staff (as well as operation staff) and thus to have sufficient knowledge to understand the links between chemistry and the generation of radiation field. This report was prepared with the primary objective to provide such knowledge to 'non-chemist'. The publication primarily focuses on three topics dealing with water chemistry, source term management and remediation techniques. One key objective of the report is to provide current knowledge regarding these topics and to address clearly related radiation protection issues. In that mind, the report prepared by the EGWC was also reviewed by radiation protection experts. In order to address various designs, PWRs, VVERs, PHWRs and BWRs are addressed within the document. Additionally, available information addressing current operating units and lessons learnt is outlined with choices that have been made for the design of new plants. Chapter 3 of this report addresses current practices regarding primary chemistry management for different designs, 'how to limit activity in the primary circuit and to minimise contamination'. General information is provided regarding activation, corrosion and transport of activated materials in the primary circuit (background on radiation field generation). Primary chemistry aspects that

Education on radiation risk in primary and middle schools in Japan

International Nuclear Information System (INIS)

Tada, Junichiro

1999-01-01

The (ionizing) radiation appears in the text of social studies in primary and middle school curriculums. The radiation is almost not involved in the text of science. Consequently, pupils know only the examples of disasters caused by the excessive radiation and have no chance to learn real natures and characters of the radiation after the compulsory education course. This situation means difficulties to give a lesson on the radiation risk. Erupting volcanoes, earthquakes and lightning are similar in danger of the excessive radiations. However, few pupils have a supernatural threat for these phenomena that ancient people do, because they have the adequate knowledge for theses after primary and middle school curriculums. This situation is a full of contrast to the case of the radiation on the major sensitivity that they have. The point is to let pupils learn that the radiation is one of the natural phenomena like heat and electricity, those exist before a birth of human being. Natural ionizing radiation sources are recommended for the first teaching material. Pupils know that the radiation is one of commonplace events, then. Radiation is one of the universe elements. Consequently, they will know that human being is evolving with the radiation exposures. The general perception on safety and danger is a kind of antinomy in Japan. A person who is following antinomy accepts only zero risk. Preschool educations will be needed to grow out of an antinomy concept on safety and danger, and to recognize the reality. A comprehensive knowledge should be provided with a full balance for the perception of risk. For an example, prejudices against HIV patients still remain in Japan, due to many belated campaigns on weak infection. People remember danger, and they do not remember the fact that is not dangerous. (Y. Tanaka)

Education on radiation risk in primary and middle schools in Japan

Energy Technology Data Exchange (ETDEWEB)

Tada, Junichiro [Japan Synchrotron Radiation Research Institute (SPring-8), Mikaduki, Hyogo (Japan)

1999-09-01

The (ionizing) radiation appears in the text of social studies in primary and middle school curriculums. The radiation is almost not involved in the text of science. Consequently, pupils know only the examples of disasters caused by the excessive radiation and have no chance to learn real natures and characters of the radiation after the compulsory education course. This situation means difficulties to give a lesson on the radiation risk. Erupting volcanoes, earthquakes and lightning are similar in danger of the excessive radiations. However, few pupils have a supernatural threat for these phenomena that ancient people do, because they have the adequate knowledge for theses after primary and middle school curriculums. This situation is a full of contrast to the case of the radiation on the major sensitivity that they have. The point is to let pupils learn that the radiation is one of the natural phenomena like heat and electricity, those exist before a birth of human being. Natural ionizing radiation sources are recommended for the first teaching material. Pupils know that the radiation is one of commonplace events, then. Radiation is one of the universe elements. Consequently, they will know that human being is evolving with the radiation exposures. The general perception on safety and danger is a kind of antinomy in Japan. A person who is following antinomy accepts only zero risk. Preschool educations will be needed to grow out of an antinomy concept on safety and danger, and to recognize the reality. A comprehensive knowledge should be provided with a full balance for the perception of risk. For an example, prejudices against HIV patients still remain in Japan, due to many belated campaigns on weak infection. People remember danger, and they do not remember the fact that is not dangerous. (Y. Tanaka)

Radiation levels on empty cylinders containing heel material

Energy Technology Data Exchange (ETDEWEB)

Shockley, C.W. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31

Empty UF{sub 6} cylinders containing heel material were found to emit radiation levels in excess of 200 mr/hr, the maximum amount stated in ORO-651. The radiation levels were as high as 335 mr/hr for thick wall (48X and 48Y) cylinders and 1050 mr/hr for thin wall (48G and 48H) cylinders. The high readings were found only on the bottom of the cylinders. These radiation levels exceeded the maximum levels established in DOT 49 CFR, Part 173.441 for shipment of cylinders. Holding periods of four weeks for thick-wall cylinders and ten weeks for thin-wall cylinders were established to allow the radiation levels to decay prior to shipment.

Efficacy of RADPAD® protection drape in reducing radiation exposure to the primary operator during Transcatheter Aortic Valve Implantation (TAVI).

Science.gov (United States)

Sharma, Divyesh; Ramsewak, Adesh; Manoharan, Ganesh; Spence, Mark S

2016-02-01

The efficacy of RADPAD® (a sterile, lead-free drape) has been demonstrated to reduce the scatter radiation to the primary operator during fluoroscopic procedures. However, the use of the RADPAD® during TAVI procedures has not been studied. Transcatheter aortic valve implantation (TAVI) is now an established treatment for patients with symptomatic severe aortic stenosis who are deemed inoperable or at high risk for conventional surgical aortic valve replacement (AVR). Consequently the radiation exposure to the patient and the interventional team from this procedure has become a matter of interest and importance. Methods to reduce radiation exposure to the interventional team during this procedure should be actively investigated. In this single center prospective study, we determined the radiation dose during this procedure and the efficacy of RADPAD® in reducing the radiation dose to the primary operator. Fifty consecutive patients due to undergo elective TAVI procedures were identified. Patients were randomly assigned to undergo the procedure with or without the use of a RADPAD® drape. There were 25 patients in each group and dosimetry was performed at the left eye level of the primary operator. The dosimeter was commenced at the start of the procedure, and the dose was recorded immediately after the end of the procedure. Fluoroscopy times and DAP were also recorded prospectively. Twenty-five patients underwent transfemoral TAVI using a RADPAD® and 25 with no-RADPAD®. The mean primary operator radiation dose was significantly lower in the RADPAD group at 14.8 mSv vs. 24.3 mSv in the no-RADPAD group (P=0.008). There was no significant difference in fluoroscopy times or dose-area products between the two patient groups. The dose to the primary operator relative to fluoroscopy time (RADPAD: slope=0.325; no RADPAD: slope=1.148; analysis of covariance F=7.47, P=0.009) and dose area product (RADPAD: slope=0.0007; no RADPAD: slope=0.002; analysis of covariance F=7

Epidemiological surveys on the effects of low-level radiation dose: a comparative assessment

International Nuclear Information System (INIS)

Rose, K.S.B.

1988-01-01

In this report, the health effects of low-level doses of radiation are considered by reference to published epidemiological surveys. The work was carried out with three objectives in mind: 1. to provide a comprehensive and critical review of the subject; 2. to seek consistent indications of particular health effects by collating results and comparing with those from surveys at moderate-level doses; 3. to provide an authoritative view on the epidemiology of low-level radiation-induced health effects. Vol E (DRAFT A) is appended and contains group collation tables. Epidemiological surveys can be conveniently divided into four classes (A, B, C, D) according to the phase of life when irradiation occurs or the effect is diagnosed. The first of the classes (A) is addressed here; this class is concerned with possible effects arising from radiation received by a parent before conception. Possible effects of preconception irradiation were identified under four broad groupings. These are Down's syndrome, ''Indicators of Reproductive Damage'' (mainly Primary Sterility, Congenital Abnormalities, Sex Ratio, Fetal Mortality, Infant Mortality), Childhood Malignancies, and Chromosomal Changes in Abortuses. Information about each survey, and comparisons with results from moderate-level dose surveys, are contained in synopses that are set out in the Appendix. (author)

Responses to the low-level-radiation controversy

International Nuclear Information System (INIS)

Bond, V.P.

1981-01-01

Some data sets dealing with the hazards of low-level radiation are discussed. It is concluded that none of these reports, individually or collectively, changes appreciably or even significantly the evaluations of possible low-level radiation effects that have been made by several authoritative national and international groups

Radiation hormesis: an outcome of exposure to low level ionizing radiation

International Nuclear Information System (INIS)

Kant, Krishan

2012-01-01

Ionizing radiation is a benign environmental agent at background levels. Human population is always exposed to ionizing radiation from natural sources. Important sources are cosmic rays which come from outer space and from the surface of the sun, terrestrial radionuclides which occur in the earths crust in various geological formations in soils, rocks, building materials, plants, water, food, air and in the human body itself. With the increasing use of radiation in health facilities, scientific research, industry and agriculture, the study of impact of low-level ionizing radiation on environment and possible health effects on future generations has been a cause of concern in recent years. As regards the effects, it is established fact that high doses of ionizing radiation are harmful to health, there exists, however, a substantial controversy regarding the effects of low doses of ionizing radiation (LLIR). In the present paper, brief review of the available literature, data and reports on stimulation by low-dose irradiation and recent data supporting radiation hormesis. A linear quadratic model has been given illustrating the validity of radiation hormesis, besides the comparison of the dose rates arising from natural and manmade sources to the Indian population. This overview summarizes various reports

Radiation exposure of airplane crews. Exposure levels

International Nuclear Information System (INIS)

Bergau, L.

1995-01-01

Even at normal height levels of modern jet airplanes, the flying crew is exposed to a radiation level which is higher by several factors than the terrestrial radiation. There are several ways in which this can be hazardous; the most important of these is the induction of malignant growths, i.e. tumours. (orig./MG) [de

Radiation therapy for primary undifferentiated carcinoma of the esophagus

International Nuclear Information System (INIS)

Ohno, Tatsuya; Yamakawa, Michitaka; Shiojima, Kazumi; Hasegawa, Masatoshi; Akimoto, Tetsuo; Nakayama, Yuko; Kitamoto, Yoshizumi; Mitsuhashi, Norio; Niibe, Hideo

1996-01-01

Eight patients with undifferentiated carcinoma of the esophagus were treated by radiation therapy. Loco-regional control was easily achieved by radiation therapy alone and no loco-regional recurrence was observed for six patients treated with total dose of more than 30 Gy. However four patients developed distant metastases and died of tumor. Median survival was 3.5 months with a range of 0 to 48 months. Only one patient is alive with no evidence of tumor for 48 months. Combination chemotherapy should be recommended for primary undifferentiated carcinoma of the esophagus because of having a high incidence of distant metastases. (author)

Imaging and characterization of primary and secondary radiation in ion beam therapy

Energy Technology Data Exchange (ETDEWEB)

Granja, Carlos, E-mail: carlos.granja@utef.cvut.cz; Opalka, Lukas [Institute of Experimental and Applied Physics, Czech Technical University in Prague (Czech Republic); Martisikova, Maria; Gwosch, Klaus [German Cancer Research Center, Heidelberg (Germany); Jakubek, Jan [Advacam, Prague (Czech Republic)

2016-07-07

Imaging in ion beam therapy is an essential and increasingly significant tool for treatment planning and radiation and dose deposition verification. Efforts aim at providing precise radiation field characterization and online monitoring of radiation dose distribution. A review is given of the research and methodology of quantum-imaging, composition, spectral and directional characterization of the mixed-radiation fields in proton and light ion beam therapy developed by the IEAP CTU Prague and HIT Heidelberg group. Results include non-invasive imaging of dose deposition and primary beam online monitoring.

Imaging and characterization of primary and secondary radiation in ion beam therapy

International Nuclear Information System (INIS)

Granja, Carlos; Opalka, Lukas; Martisikova, Maria; Gwosch, Klaus; Jakubek, Jan

2016-01-01

Imaging in ion beam therapy is an essential and increasingly significant tool for treatment planning and radiation and dose deposition verification. Efforts aim at providing precise radiation field characterization and online monitoring of radiation dose distribution. A review is given of the research and methodology of quantum-imaging, composition, spectral and directional characterization of the mixed-radiation fields in proton and light ion beam therapy developed by the IEAP CTU Prague and HIT Heidelberg group. Results include non-invasive imaging of dose deposition and primary beam online monitoring.

Radiation doses and possible radiation effects of low-level, chronic radiation in vegetation

International Nuclear Information System (INIS)

Rhoads, W.A.; Franks, L.A.

1975-01-01

Measurements were made of radiation doses in soil and vegetation in Pu-contaminated areas at the Nevada Test Site with the objective of investigating low-level, low-energy gamma radiation (with some beta radiation) effects at the cytological or morphological level in native shrubs. In this preliminary investigation, the exposure doses to shrubs at the approximate height of stem apical meristems were estimated from 35 to 140 R for a ten-year period. The gamma exposure dose estimated for the same period was 20.7 percent +- 6.4 percent of that recorded by the dosimeters used in several kinds of field instrument surveys. Hence, a survey instrument reading made at about 25 cm in the tops of shrubs should indicate about 1 / 5 the dosimeter-measured exposures. No cytology has yet been undertaken because of the drought since last winter. (auth)

Chromosome Aberration on High Level Background Natural Radiation Areas

International Nuclear Information System (INIS)

Yanti-Lusiyanti; Zubaidah-Alatas

2001-01-01

When the body is irradiated, all cells can suffer cytogenetic damage that can be seen as structural damage of chromosome in the lymphocytes. People no matter where they live in world are exposed to background radiation from natural sources both internal and external such as cosmic radiation, terrestrial radiation, cosmogenic radiation radon and thoron. Level of area natural ionizing radiation is varies depending on the altitude, the soil or rock conditions, particular food chains and the building materials and construction features. Level of normal areas of background exposure is annual effective dose 2.4 mSv and the high level areas of background exposure 20 mSv. This paper discuses the frequency of aberration chromosome especially dysenteries in several countries having high level radiation background. It seems that frequency of chromosome aberrations increase, generally with the increase of age of the people and the accumulated dose received. (author)

Health effects of low level radiation

International Nuclear Information System (INIS)

Hattori, Sadao

1998-01-01

In 1982, Prof. Thomas Don Luckey of Missouri Univ. asserted 'Radiation Hormesis' on the Journal of Health Physics and he published two books. CRIEPI initiated the research program on Radiation Hormesis following his assertion to confirm 'is it true or not?' After nearly ten year research activities on data surveys and animal tests with many Universities, we are realizing scientific truth of bio-positive effects by low level radiation exposures. The interesting bio-positive effects we found could be categorized in following five groups. 1) Rejuvenation of cells such as increase of SOD and cell membrane permeability, 2) Moderation of psychological stress through response of key enzymes, 3) Suppression and therapy of adult-diseases such as diabetes and hypertension, 4) Suppression of cancer through enhancement of immune systems such as lymphocytes, 5) Suppression of cancer and ratio-adaptive response by activation of DNA repair and apoptosis. In the responses of many specialists to our initiation of radiation hormesis research program following T.D. Luckey's claim about low level radiation, I have to pick up for the first, the great success of Prof. Sakamoto. Prof. Sakamoto had been already applying whole body low dose irradiation for ten years before our radiation hormesis research started on the therapy to suppress the cancer reappearing after treatment. He reported about his successful trial to real patients and showed an enhancement of immune system. (author)

Health effects of low level radiation

Energy Technology Data Exchange (ETDEWEB)

Hattori, Sadao [Central Research Inst. of Electric Power Industry, Tokyo (Japan)

1998-12-31

In 1982, Prof. Thomas Don Luckey of Missouri Univ. asserted `Radiation Hormesis` on the Journal of Health Physics and he published two books. CRIEPI initiated the research program on Radiation Hormesis following his assertion to confirm `is it true or not?` After nearly ten year research activities on data surveys and animal tests with many Universities, we are realizing scientific truth of bio-positive effects by low level radiation exposures. The interesting bio-positive effects we found could be categorized in following five groups. 1) Rejuvenation of cells such as increase of SOD and cell membrane permeability, 2) Moderation of psychological stress through response of key enzymes, 3) Suppression and therapy of adult-diseases such as diabetes and hypertension, 4) Suppression of cancer through enhancement of immune systems such as lymphocytes, 5) Suppression of cancer and ratio-adaptive response by activation of DNA repair and apoptosis. In the responses of many specialists to our initiation of radiation hormesis research program following T.D. Luckey`s claim about low level radiation, I have to pick up for the first, the great success of Prof. Sakamoto. Prof. Sakamoto had been already applying whole body low dose irradiation for ten years before our radiation hormesis research started on the therapy to suppress the cancer reappearing after treatment. He reported about his successful trial to real patients and showed an enhancement of immune system. (author)

Grazing rates of Calanus finmarchicus on Thalassiosira weissflogii cultured under different levels of ultraviolet radiation.

Directory of Open Access Journals (Sweden)

David M Fields

Full Text Available UVB alters photosynthetic rate, fatty acid profiles and morphological characteristics of phytoplankton. Copepods, important grazers of primary production, select algal cells based upon their size, morphological traits, nutritional status, and motility. We investigated the grazing rates of the copepod Calanus finmarchicus on the diatom Thalassiosira weissflogii cultured under 3 levels of ultraviolet radiation (UVR: photosynthetically active radiation (PAR only (4 kJ-m(-2/day, and PAR supplemented with UVR radiation at two intensities (24 kJ-m(-2/day and 48 kJ-m(-2/day. There was no significant difference in grazing rates between the PAR only treatment and the lower UVR treatment. However, grazing rates were significantly (∼66% higher for copepods feeding on cells treated with the higher level of UVR. These results suggest that a short-term increase in UVR exposure results in a significant increase in the grazing rate of copepods and, thereby, potentially alters the flow rate of organic matter through this component of the ecosystem.

Overview of the hazards of low-level exposure to radiation

International Nuclear Information System (INIS)

Ritenour, E.R.

1984-01-01

In this chapter the authors are concerned with low-level radiation, doses of ionizing radiations that are ten to thousands of times smaller than those required to contract ARS. Low-level radiation may be defined as an absorbed dose of 10 rem or less delivered over a short period of time. A larger dose delivered over a long period of time, for instance, 50 rem in 10 years, may also be considered low level. The definition is purposely loose so as to cover a wide variety of sources of radiation exposure, such as natural background (100 mrem/year) occupational exposures (<5 rem/year), and medical applications, such as diagnostic radiography (<1 rem). Low-level radiation exposure does not produce ARS. The health effects that may be of concern in regard to low-level radiation are its long-term sequelae. Studies of survivors of high-level radiation exposure (both human and laboratory animals) have indicated that there are three health effects that should be examined at low levels of exposure: induction of cancer, birth abnormalities (from irradiation in utero), and genetic effects. No other long-term effects of low-level exposure have been conclusively demonstrated in animals or humans

Low-level radiation risks in people

International Nuclear Information System (INIS)

Goloman, M.; Filjushkin, V. lgor

1993-01-01

Using the limited human data plus the relationships derived from the laboratory, a leukemia risk model has been developed as well as a suggested model for other cancers in people exposed to low levels of radiation. Theoretical experimental and epidemiological evidence will be presented in an integrated stochastic model for projection of radiation-induced cancer risks

Low-level radiation waste management system

International Nuclear Information System (INIS)

Kubofcik, K.W.

1990-01-01

This patent describes a low-level radiation waste container set for use in conjunction with an open-topped receptacle. It comprises: a receptacle liner having a closed end and an open end, the receptacle liner sized for deployment as an inserted liner in an open-topped receptacle for collecting low-level radiation waste material within the receptacle liner within the open-topped receptacle; a cover sized and shaped to fit over the open top of the open-topped receptacle and the receptacle liner therein with the cover is in a closed position. The cover having a depending skirt which, when the cover is in the closed position, extends downwardly to overlap the open-topped receptacle adjacent the open top thereof and a portion of the receptacle liner received therein; and the receptacle liner and cover being fabricated of flexible radiation shielding material

Effective radiation therapy on two cases of primary Ewing's sarcoma of the rib

International Nuclear Information System (INIS)

Monzen, Yoshio; Nakanishi, Kazue; Ajimu, Akira; Ishida, Yutaka; Fujimoto, Toshifumi; Hayashi, Kuniaki; Hombo, Zenichiro; Amamoto, Yuhei.

1987-01-01

Two cases of primary Ewing's sarcoma of the rib are reported, in which radiation therapy was quite effective. Case 1 was an 18-year-old female who had had an operation and radiation therapy for Ewing's sarcoma of the left 7th rib. She was referred to our hospital after a recurrent tumor was found. Radiation therapy (tumor dose 46.2 Gy) and chemotherapy were given. The tumor disappeared and there has been no relapse for 1 year and 3 months after the treatment. Case 2 was a 2-year-old-infant. Radiation therapy (tumor dose 74 Gy) was given for primary Ewing's sarcoma of the left 6th rib. The tumor became small and was successfully removed at operation. There has been no relapse or distant metastasis for 8 months following the operation. We emphasize the importance of multidisciplinary treatment in case 1 and the usefulness of preoperative radiotherapy in case 2. (author)

Low-level radiation: biological interactions, risks, and benefits. A bibliography

International Nuclear Information System (INIS)

1978-09-01

The bibliography contains 3294 references that were selected from the Department of Energy's data base (EDB). The subjects covered are lower-level radiation effects on man, environmental radiation, and other biological interactions of radiation that appear to be applicable to the low-level radiation problem

Low-level radiation: biological interactions, risks, and benefits. A bibliography

Energy Technology Data Exchange (ETDEWEB)

None

1978-09-01

The bibliography contains 3294 references that were selected from the Department of Energy's data base (EDB). The subjects covered are lower-level radiation effects on man, environmental radiation, and other biological interactions of radiation that appear to be applicable to the low-level radiation problem.

Measurement and calculation of radiation sources in the primary cooling system of JOYO

International Nuclear Information System (INIS)

Suzuki, S.; Iizawa, K.; Ohtani, N.; Kobayashi, T.; Horie, J.; Handa, H.

1987-01-01

Production and transfer of radiation sources in the primary cooling system are important consideration in the LMFBR plant from the viewpoint of radiation protection and shielding design. These items were evaluated with calculations and/or measurements in the Japanese experimental fast reactor JOYO. In this study, calculations were made with the DOT3.5 0 two-dimensional discrete ordinate transport code to determine the neutron flux and production rate distributions of radiation sources in the reactor vessel. Using the DOT results, the behavior in primary coolant sodium of the CP (radioactive corrosion products) which were released from the reactor structural material was also calculationally analyzed with the PSYCHE code developed by PNC. These analytical results were compared with the measured results to get the verification of analysis methods and to estimate the accuracy of calculations

Low-level radiation: The cancer controversy

International Nuclear Information System (INIS)

Stewart, A.M.

1990-01-01

According to early studies it would be safe to assume there are no late effects of radiation apart from cancer, no lasting selective effects of the early deaths of A-bomb victims, and no cancer risk at low dose levels (below 20 rad). The nuclear establishment had good reason to believe that a potentially dangerous situation had been completely defused, and optimists were still free to regard daily exposure to background radiation as a benign influence. For several years the only indication to the contrary was the Oxford survey's finding on prenatal X-rays. But today we face the possibility that there are other late effects of radiation besides cancer; and the possibility that the selection effects of the two nuclear explosions are still reflected in death rates among survivors and are the reason why no cancer effects have been found at low dose levels. If these possibilities are confirmed, we may one day realize how fortunate it was that the Oxford survey findings put a brake on the enthusiasms of nuclear power advocates. Otherwise, we might never have pressed for direct studies of the effects of low doses of radiation. 7 refs

The mechanism for the primary biological effects of ionizing radiation

International Nuclear Information System (INIS)

Byakov, Vsevolod M; Stepanov, Sergei V

2006-01-01

The primary biological response of living organisms to the passage of fast charged particles is traditionally believed to be dominated by the chemical reactions of the radical products from the radiolysis of cellular water (OH, H, e aq - , O 2 - , H 2 O 2 ) and by the bioradicals that they produce (and which can also result from the direct electronic activation of biomolecules). This understanding has provided insight into how ionizing radiations affect biological systems and, most importantly, what radioprotection and radiosensibilizing effects are produced by chemical compounds introduced into an organism. However, a number of key radiobiological facts remain unexplained by the current theory, stimulating a search for other biologically active factors that may be triggered by radiation. This review examines a fact that is usually ignored in discussing the biological impact of ionizing radiation: the local increase in acidity in the water solution along the track of a charged particle. The acidity in the track is very different from its value for cellular water in a living organism. Biological processes are well-known to be highly sensitive to changes in the environmental acidity. It seems that the biological impact of ionizing radiations is dominated not by the water radiolysis products (mostly radicals) listed above but particles of a different nature, hydroxonium ions H 3 O + , where the term hydroxonium refer to protonated water molecules. This modification of the mechanism of primary radiobiological effects is in good agreement with experimental data. In particular, the extremal dependence of the relative biological efficiency (RBE) of radiations on their ionizing energy losses is accounted for in quantitative terms, as is the increase in the RBE in the relativistic energy range. (reviews of topical problems)

Radiobiologic effects at low radiation levels

International Nuclear Information System (INIS)

Casarett, G.W.

1975-01-01

Data are reviewed on the effects of low radiation doses on mammals. Data from the 1972 report on the Biological Effects of Ionizing Radiation issued by the Advisory Committee of the National Academy of Sciences and National Research Council are discussed. It was concluded that there are certain radiosensitive systems in which low doses of radiation may cause degenerative effects, including gametogenic epithelium, lens of the eye, and developing embryos. Despite extensive investigation of genetic effects, including chromosomal effects, neither the amount of change that will be caused by very low levels of irradiation nor the degree of associated detriment is known

Acceptable level of radiation risk and its perception

International Nuclear Information System (INIS)

Kusama, Tomoko; Shinozaki, Motoshi; Yoshizawa, Yasuo

1987-01-01

The acceptable level of radiation risk for public members, that is 10 -5 /y, was proposed by ICRP and other international organizations. We studied to survey basic procedures of deriving this value and to derive an acceptable risk value in Japan by using similar procedures. The basic procedures to derive 10 -5 /y were found as follows; (1) 0.1 percent of annual mortality from all diseases, (2) 0.1 percent of life time risk, (3) one percent of mortality from all causes in each age cohort and (4) corresponding value to 1 mSv annual radiation exposure. From these bases we derived the value of 10 -5 /y as acceptable risk level in Japan. The perception to risk level of 10 -5 /y in conventional life was investigated by means of questionnaires for 1,095 college students living in Tokyo. The risks considered in this study were natural background radiation, coffee, skiing, X-ray diagnosis, spontaneous cancer, passive smoking and air pollution. The most acceptable risk was the risk related with natural background radiation. And the risk of natural background radiation was more easily accepted by the students who had knowledges on natural background radiation. On the other hand, the risk from air pollution or passive smoking was the most adverse one. (author)

Effects of high vs low-level radiation exposure

International Nuclear Information System (INIS)

Bond, V.P.

1983-01-01

In order to appreciate adequately the various possible effects of radiation, particularly from high-level vs low-level radiation exposure (HLRE, vs LLRE), it is necessary to understand the substantial differences between (a) exposure as used in exposure-incidence curves, which are always initially linear and without threshold, and (b) dose as used in dose-response curves, which always have a threshold, above which the function is curvilinear with increasing slope. The differences are discussed first in terms of generally familiar nonradiation situations involving dose vs exposure, and then specifically in terms of exposure to radiation, vs a dose of radiation. Examples are given of relevant biomedical findings illustrating that, while dose can be used with HLRE, it is inappropriate and misleading the LLRE where exposure is the conceptually correct measure of the amount of radiation involved

Assessment of dose level of ionizing radiation in army scrap

International Nuclear Information System (INIS)

Abdel Hamid, S. M.

2010-12-01

Radiation protection is the science of protecting people and the environment from the harmful effects of ionizing radiation, which includes both particle radiation and high energy radiation. Ionizing radiation is widely used in industry and medicine. Any human activity of nuclear technologies should be linked to the foundation of scientific methodology and baseline radiation culture to avoid risk of radiation and should be working with radioactive materials and expertise to understand, control practices in order to avoid risks that could cause harm to human and environment. The study was conducted in warehouses and building of Sudan air force Khartoum basic air force during September 2010. The goal of this study to estimate the radiation dose and measurement of radioactive contamination of aircraft scrap equipment and increase the culture of radiological safety as well as the concept of radiation protection. The results showed that there is no pollution observed in the contents of the aircraft and the spire part stores outside, levels of radiation dose for the all contents of the aircraft and spire part within the excitable level, except temperature sensors estimated radiation dose about 43 μSv/h outside of the shielding and 12 μSv/h inside the shielding that exceeded the internationally recommended dose level. One of the most important of the identification of eighteen (18) radiation sources used in temperature and fuel level sensors. These are separated from the scrap, collected and stored in safe place. (Author)

Randomized study of control of the primary tumor and survival using preoperative radiation, radiation alone, or surgery alone in head and beck carcinomas

International Nuclear Information System (INIS)

Hintz, B.; Charyulu, K.; Chandler, J.R.; Sudarsanam, A.; Garciga, C.

1979-01-01

Fifty-five selected patients with previously untreated squamous cell carcinoma of the head and neck regions were studied in a randomized, prospective manner. The three treatment categories were primary radiation (Gp R), primary surgery (Gp S), and preoperative radiation of 4000 rads in four weeks (Gp R/S). The local control rates for the 44 evaluable patients with a two-year minimum followup were 24%, 39%, and 43%, respectively. Further treatment attempts in patients failing initial therapy yielded local control rates of 35%, 39%, and 43% for Gp R, Gp S, and Gp R/S, respectively. None of the local control rates nor the corresponding survival curves were significantly different at P < 0.10. However, the group sizes were sufficiently small that true differences might not have been detected. Postoperative complications were higher in the primary radiation failures subsequently operated upon compared to the primary surgery group (P = 0.07). A table is included in which the types of postoperative complications are listed and enumerated according to treatment regime

Low-level radiation effects: a fact book

International Nuclear Information System (INIS)

Brill, A.B.; Adelstein, S.J.; Saenger, E.L.; Webster, E.W.

1982-01-01

Low Level Raidation Effects: A Fact Book, prepared by the Society of Nuclear Medicine Subcommittee on the Risks of Low-Level Ionizing Radiation, attempts to examine the health effects of small doses of radiation. For immediate questions, this work provides a well-organized brief summary of recent radiologic data from refereed scientific literature and from the publications of advisory groups such as the National Council of Radiation Protection and Measurement (NCRP), the International Commission on Radiological Protection (ICRP), the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), and the National Academy of Sciences (NAS). Since it consists almost entirely of tables and graphs from the above-mentioned sources along with summary paragraphs, the Fact Book is very useful in the preparation of lectures. The book is divided into seven sections. Chapter One, Glossary, Units and Conversion Factors, is useful because nearly all data given in the rest of the book is in conventional units and should be converted to SI units for future technical audiences. Chapter 2, Radiobiology, covers the fundamental principles of the field. Chapter 3, Radiation Doses, can be used to help an audience appreciate the relative magnitudes of radiation exposures they may read about or encounter. Chapter 4, Late Somatic Effects of Low Doses of Ionizing Radiation, gives data concerning cancer induction and embryonic effects, and Chapter 5 provides data on genetic effects Chapter 6, Risks, Statistical Facts and Public Perception can be used to compare the risks of radiation exposure with more commonly encountered risks

Measured Radiation and Background Levels During Transmission of Megawatt Electron Beams Through Millimeter Apertures

Energy Technology Data Exchange (ETDEWEB)

Alarcon, Ricardo [Arizona State University, Glendale, AZ (United States); Balascuta, S. [Arizona State University, Glendale, AZ (United States); Benson, Stephen V. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Bertozzi, William [Massachusetts Institute of Technology, Cambridge, MA (United States); Boyce, James R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Cowan, Ray [Massachusetts Institute of Technology, Cambridge, MA (United States); Douglas, David R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Evtushenko, Pavel [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Fisher, P. [Massachusetts Institute of Technology, Cambridge, MA (United States); Ihloff, Ernest E. [Hampton University, Hampton, VA (United States); Kalantarians, Narbe [Hampton University, Hampton, VA (United States); Kelleher, Aidan Michael [Massachusetts Institute of Technology, Cambridge, MA (United States); Krossler, W. J. [William and Mary College, Williamsburg, VA (United States); Legg, Robert A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Long, Elena [University of New Hampshire, Durham, NH (United States); Milner, Richard [Massachusetts Institute of Technology, Cambridge, MA (United States); Neil, George R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Ou, Longwu [Massachusetts Institute of Technology, Cambridge, MA (United States); Schmookler, Barack Abraham [Massachusetts Institute of Technology, Cambridge, MA (United States); Tennant, Christopher D. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Tschalar, C. [Massachusetts Institute of Technology, Cambridge, MA (United States); Williams, Gwyn P. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Zhang, Shukui [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2013-11-01

We report measurements of photon and neutron radiation levels observed while transmitting a 0.43 MW electron beam through millimeter-sized apertures and during beam-off, but accelerating gradient RF-on, operation. These measurements were conducted at the Free-Electron Laser (FEL) facility of the Jefferson National Accelerator Laboratory (JLab) using a 100 MeV electron beam from an energy-recovery linear accelerator. The beam was directed successively through 6 mm, 4 mm, and 2 mm diameter apertures of length 127 mm in aluminum at a maximum current of 4.3 mA (430 kW beam power). This study was conducted to characterize radiation levels for experiments that need to operate in this environment, such as the proposed DarkLight Experiment. We find that sustained transmission of a 430 kW continuous-wave (CW) beam through a 2 mm aperture is feasible with manageable beam-related backgrounds. We also find that during beam-off, RF-on operation, multipactoring inside the niobium cavities of the accelerator cryomodules is the primary source of ambient radiation when the machine is tuned for 130 MeV operation.

Thermal modeling of radiation and convection sections of primary reformer of ammonia plant

International Nuclear Information System (INIS)

Sanaye, Sepehr; Baheri, Ehsan

2007-01-01

The primary reformer is basically a furnace containing burners and tubes packed with supported nickel catalyst. Due to the strongly endothermic nature of the process, a large amount of heat is supplied by fuel burning (commonly natural gas) in the furnace chamber. Accordingly, selection of primary reformer operating parameters has an important influence on reduction of operating costs and increasing the reactor performance (conversion efficiency). In this paper, the radiation and convection sections of primary reformer are investigated. The effects of key parameters on reformer performance are studied and the related developed software program is presented. The stirred-reactor furnace model which was used to simulate the radiation section of primary reformer was found to make substantially correct predictions of the overall heat transfer process in the furnace. Comparison of the numerical data obtained from the simulation program with the measured data collected from primary reformer of Razi petrochemical plant showed a mean difference of 0.23% in estimating produced hydrogen mole fraction, as well as 1.7% and 7.25% in computing the outlet temperature of process fluids and induced draft fan (ID) speed, respectively

Stabilization of primary mobile radiation defects in MgF{sub 2} crystals

Energy Technology Data Exchange (ETDEWEB)

Lisitsyn, V.M. [National Research Tomsk Polytechnic University, pr. Lenina 30, Tomsk 634050 (Russian Federation); Lisitsyna, L.A. [State University of Architecture and Building, pl. Solyanaya 2, Tomsk 634003 (Russian Federation); Popov, A.I., E-mail: popov@ill.fr [Institute of Solid State Physics, University of Latvia, 8 Kengaraga Str., LV-1063 Riga (Latvia); Kotomin, E.A. [Institute of Solid State Physics, University of Latvia, 8 Kengaraga Str., LV-1063 Riga (Latvia); Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart (Germany); Abuova, F.U.; Akilbekov, A. [L.N. Gumilyov Eurasian National University, 3 Munaitpasova Str., Astana (Kazakhstan); Maier, J. [Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart (Germany)

2016-05-01

Non-radiative decay of the electronic excitations (excitons) into point defects (F–H pairs of Frenkel defects) is main radiation damage mechanism in many ionic (halide) solids. Typical time scale of the relaxation of the electronic excitation into a primary, short-lived defect pair is about 1–50 ps with the quantum yield up to 0.2–0.8. However, only a small fraction of these primary defects are spatially separated and survive after transformation into stable, long-lived defects. The survival probability (or stable defect accumulation efficiency) can differ by orders of magnitude, dependent on the material type; e.g. ∼10% in alkali halides with f.c.c. or b.c.c. structure, 0.1% in rutile MgF{sub 2} and <0.001% in fluorides MeF{sub 2} (Me: Ca, Sr, Ba). The key factor determining accumulation of stable radiation defects is stabilization of primary defects, first of all, highly mobile hole H centers, through their transformation into more complex immobile defects. In this talk, we present the results of theoretical calculations of the migration energies of the F and H centers in poorely studied MgF{sub 2} crystals with a focus on the H center stabilization in the form of the interstitial F{sub 2} molecules which is supported by presented experimental data.

Multiple chromosome aberrations among newborns from high level natural radiation area and normal level natural radiation area of south west coast of Kerala

International Nuclear Information System (INIS)

Soren, D.C.; Ramachandran, E.N.; Karuppasamy, C.V.; Cheriyan, V.D.; Anil Kumar, V.; Koya, P.K.M.; Seshadri, M.

2010-01-01

Cord blood samples were collected in heparin vials and microculture techniques employed to obtain good metaphase chromosome spreads. In cytogenetic studies on newborns cells with multiple aberrations were recorded in 57 from a total of 27285 newborns (1266972 cells). Of these 17294 newborns (964140 cells) were from High Level Natural Radiation Area (HLNRA) and 9991 newborns (302832 cells) from Normal Level Natural Radiation Area (NLNRA). Cells with multiple aberrations were observed in 38 and 19 newborns from High and Normal Level Natural Radiation Area respectively. On an average one cell with multiple aberrations was observed among 479 newborns. Cells with multiple aberrations were observed in newborns from HLNRA as well as NLNRA in both males and females. Gender difference of newborns, maternal age group and background radiation levels did not seem to have any influence in the occurrence of Multiple chromosome aberrations

Regulatory control of low level radiation exposure in Tanzania

International Nuclear Information System (INIS)

Nyanda, A.M.; Muhogora, W.E.

1997-01-01

In Tanzania, the radiation protection law was issued in 1983. Under this law, the National Radiation Commission is responsible for safe uses of ionizing radiation. The regulatory control of the resulting doses from the uses of radiation sources in medicine, industry, research and teaching is presented. The system of control reflects the existing interactions between the National Radiation Commission and users through the established radiation protection infrastructure. From the national dose registry data, it is found that the highest annual individual doses over 10 years ago, came from less than 5% of total monitored workers and were in the range 10 - 15 mSv y -1 . The experienced radiation levels in uncontrolled areas of potential workplaces is less than 1 μSv h -1 . The possibility for associating such low dose levels to the effectiveness of the existing regulatory dose control framework is discussed. Despite of this achievement, the need to improve further the radiation protection and safety programs is found necessary. (author)

Intermediate bands versus levels in non-radiative recombination

International Nuclear Information System (INIS)

Luque, Antonio; Marti, Antonio; Antolin, Elisa; Tablero, Cesar

2006-01-01

There is a practical interest in developing semiconductors with levels situated within their band gap while preventing the non-radiative recombination that these levels promote. In this paper, the physical causes of this non-radiative recombination are analyzed and the increase in the density of the impurities responsible for the mid-gap levels to the point of forming bands is suggested as the means of suppressing the recombination. Simple models supporting this recommendation and helping in its quantification are presented

Acceptable level of radiation risk and its perception

Energy Technology Data Exchange (ETDEWEB)

Kusama, Tomoko; Shinozaki, Motoshi; Yoshizawa, Yasuo

1987-03-01

The acceptable level of radiation risk for public members, that is 10/sup -5//y, was proposed by ICRP and other international organizations. We studied to survey basic procedures of deriving this value and to derive an acceptable risk value in Japan by using similar procedures. The basic procedures to derive 10/sup -5//y were found as follows; (1) 0.1 percent of annual mortality from all diseases, (2) 0.1 percent of life time risk, (3) one percent of mortality from all causes in each age cohort and (4) corresponding value to 1 mSv annual radiation exposure. From these bases we derived the value of 10/sup -5//y as acceptable risk level in Japan. The perception to risk level of 10/sup -5//y in conventional life was investigated by means of questionnaires for 1,095 college students living in Tokyo. The risks considered in this study were natural background radiation, coffee, skiing, X-ray diagnosis, spontaneous cancer, passive smoking and air pollution. The most acceptable risk was the risk related with natural background radiation. And the risk of natural background radiation was more easily accepted by the students who had knowledges on natural background radiation. On the other hand, the risk from air pollution or passive smoking was the most adverse one.

Background compensation for a radiation level monitor

Science.gov (United States)

Keefe, D.J.

1975-12-01

Background compensation in a device such as a hand and foot monitor is provided by digital means using a scaler. With no radiation level test initiated, a scaler is down-counted from zero according to the background measured. With a radiation level test initiated, the scaler is up-counted from the previous down-count position according to the radiation emitted from the monitored object and an alarm is generated if, with the scaler having crossed zero in the positive going direction, a particular number is exceeded in a specific time period after initiation of the test. If the test is initiated while the scale is down-counting, the background count from the previous down- count stored in a memory is used as the initial starting point for the up-count.

Results of primary radiation therapy in early vocal cord cancers

International Nuclear Information System (INIS)

Mehta, S.A.; Sarkar, S.; Mehta, M.S.; Marfatia, P.T.; Choudhary, A.J.; Mehta, A.R.

1991-01-01

Results of 74 patients treated by primary radiation therapy with curative intent at the Tata Memorial Hospital between January 1980 and December 1984 are reported. Thirty three (44.6%) were classified as TlaNO, twenty five (33.8%) as TlbNO, ten (13.5%) as T2NO and six(8.1%) as TisNO. The 5-year actuarial survival was 92% and disease-free survival was 85%. Thirteen patients (17.5%) failed locally, seven (53.8%) of whom were salvaged by surgery. Radiation side-effects were minimal and there were no long term complications. Anterior commissure involvement did not affect the local recurrence rates. (author). 19 refs., 1 tabs

About the principles of radiation level normalization

International Nuclear Information System (INIS)

Nosovskij, A.V.

2000-01-01

The paper highlights the impact being made by the radiation level normalization principles upon the social and economic indicators. The newly introduced radiation safety standards - 97 are taken as an example. It is emphasized that it is necessary to use a sound approach while defining radiation protection standards, taking into consideration economic and social factors existing in Ukraine at the moment. Based on the concept of the natural radiation background and available results of the epidemiological surveys, the dose limits are proposed for the radiation protection standards. The paper gives a description of the dose limitation system recommended by the International Committee for Radiation Protection. The paper highlights a negative impact of the line non threshold concept, lack of special knowledge in the medical service and mass media to make decisions to protect people who suffered from the Chernobyl accident

Radiation transport in high-level waste form

International Nuclear Information System (INIS)

Arakali, V.S.; Barnes, S.M.

1992-01-01

The waste form selected for vitrifying high-level nuclear waste stored in underground tanks at West Valley, NY is borosilicate glass. The maximum radiation level at the surface of a canister filled with the high-level waste form is prescribed by repository design criteria for handling and disposition of the vitrified waste. This paper presents an evaluation of the radiation transport characteristics for the vitreous waste form expected to be produced at West Valley and the resulting neutron and gamma dose rates. The maximum gamma and neutron dose rates are estimated to be less than 7500 R/h and 10 mRem/h respectively at the surface of a West Valley canister filled with borosilicate waste glass

Epidemiological studies in high-background radiation areas its potential contribution to evaluating risk of low-level radiation

International Nuclear Information System (INIS)

Akiba, Suminori; Nair, R.K.; Nakamura, Seiichi; Mizuno, Shoich

2008-01-01

The health effect of low-level ionizing radiation is yet unclear. As pointed out by Upton in his review (Upton, 1989), low-level ionizing radiation seems to have different biological effects from what high-level radiation has. Its evaluation requires epidemiological studies of scale-large cohorts (ICRP 99, 2005) such of atomic bomb survivors and nuclear workers. Epidemiological studies in high-background radiation (HBR) areas are also expected to make a significant contribution toward this end. Among several HBR areas in the world, Yangjiang, Guangdong Province in China, Karunagappally in Kerala State of India, Manawalakurichi and Koodankulam in Tamil Nadu of India, and Ramsar in Iran are important areas where epidemiological studies are possible, because of their relatively high background radiation levels and large population sizes. (author)

Variation in well-head gamma radiation levels at the Nigerian ...

African Journals Online (AJOL)

It was generally observed that the level of radiation around the well heads is less than 20x 10-12mSv/hr, which is in agreement with the International Atomic Energy Agency\\'s standard on ionizing radiation background level. Keywords: Radiation, crude oil, radionuclide, contaminant, exposure. Nigerian Journal of Physics ...

Ionizing radiation: levels and effects. Volume I. Levels

International Nuclear Information System (INIS)

1972-01-01

This is the sixth substantive report of the United Nations Scientific Committee on the Effects of Atomic Radiation to the General Assembly. It reviews the levels of radiation received from all sources to which man is exposed and, among the effects of ionizing radiation, it considers the genetic effects, the effects on the immune response and the induction of malignancies in animals and man. These are not the only effects of ionizing radiation. The acute consequences of massive amounts of radiation that may be received accidentally or during nuclear warfare are not reviewed here (the short discussion of this subject in the 1962 report is still largely valid, at least as an introduction), nor are the effects on the nervous system and the induction of chromosome anomalies in somatic cells, which were both considered by the Committee in its 1969 report. Unlike previous reports of the Committee, the present report is submitted to the General Assembly without the technical annexes in which the evidence considered by the Committee is discussed in detail and in which the bases for the Committee's conclusions, which are stated in the report, are fully documented. However, the annexes are being made available at the same time as the report in a separate publication, issued in two volumes and the Committee wishes to draw the attention of the General Assembly to the fact that the separation of the report from the annexes is for convenience only and that major importance attaches to the scientific evidence given in the annexes.

Analysis of nodal coverage utilizing image guided radiation therapy for primary gynecologic tumor volumes

Energy Technology Data Exchange (ETDEWEB)

Ahmed, Faisal [University of Utah School of Medicine, Salt Lake City, UT (United States); Loma Linda University Medical Center, Department of Radiation Oncology, Loma Linda, CA (United States); Sarkar, Vikren; Gaffney, David K.; Salter, Bill [Department of Radiation Oncology, University of Utah, Salt Lake City, UT (United States); Poppe, Matthew M., E-mail: matthew.poppe@hci.utah.edu [Department of Radiation Oncology, University of Utah, Salt Lake City, UT (United States)

2016-10-01

Purpose: To evaluate radiation dose delivered to pelvic lymph nodes, if daily Image Guided Radiation Therapy (IGRT) was implemented with treatment shifts based on the primary site (primary clinical target volume [CTV]). Our secondary goal was to compare dosimetric coverage with patient outcomes. Materials and methods: A total of 10 female patients with gynecologic malignancies were evaluated retrospectively after completion of definitive intensity-modulated radiation therapy (IMRT) to their pelvic lymph nodes and primary tumor site. IGRT consisted of daily kilovoltage computed tomography (CT)-on-rails imaging fused with initial planning scans for position verification. The initial plan was created using Varian's Eclipse treatment planning software. Patients were treated with a median radiation dose of 45 Gy (range: 37.5 to 50 Gy) to the primary volume and 45 Gy (range: 45 to 64.8 Gy) to nodal structures. One IGRT scan per week was randomly selected from each patient's treatment course and re-planned on the Eclipse treatment planning station. CTVs were recreated by fusion on the IGRT image series, and the patient's treatment plan was applied to the new image set to calculate delivered dose. We evaluated the minimum, maximum, and 95% dose coverage for primary and nodal structures. Reconstructed primary tumor volumes were recreated within 4.7% of initial planning volume (0.9% to 8.6%), and reconstructed nodal volumes were recreated to within 2.9% of initial planning volume (0.01% to 5.5%). Results: Dosimetric parameters averaged less than 10% (range: 1% to 9%) of the original planned dose (45 Gy) for primary and nodal volumes on all patients (n = 10). For all patients, ≥99.3% of the primary tumor volume received ≥ 95% the prescribed dose (V95%) and the average minimum dose was 96.1% of the prescribed dose. In evaluating nodal CTV coverage, ≥ 99.8% of the volume received ≥ 95% the prescribed dose and the average minimum dose was 93%. In

Environmental gamma radiation levels around various DAE research centres

International Nuclear Information System (INIS)

Takale, R.A.; Swarnakar, M.; Shetty, P.G.; Sahu, S.K.; Pandit, G.G.

2014-01-01

This paper presents the gamma radiation levels of four research centres viz. Bhabha Atomic Research Centre (BARC), Trombay; Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam; Variable Energy Cyclotron Centre (VECC), Kolkata; Raja Ramanna Centre for Advanced Technology (RRCAT), Indore; and an industry Board of Radiation and Isotope Technology (BRIT), Vashi. BARC is India's premier nuclear research facility and is a multi-disciplinary research centre with extensive infrastructure for advanced research and development (R and D). IGCAR, Kalpakkam is engaged in scientific research and advanced engineering programme towards the development of Fast Breeder Reactor technology. VECC Kolkata is dedicated to carry out frontier R and D in the fields of Accelerator Science and Technology, Nuclear Science (Theoretical and Experimental), and Material Science etc. RRCAT, Indore has rapidly grown into a premier institute for R and D in lasers, accelerators and their applications. BRIT, Vashi unit is involved in production, development, and supply of radioisotope based products and provision of isotope applications, radiation processing, radio analytical services etc. With an objective to keep a watch on the prevailing environmental background gamma radiation level around all the DAE installations, routine monitoring programme are being carried out using the Thermo Luminescent Dosimeters (TLDs). TLDs provide the simple, inexpensive and precise measurement of small, integrated, external gamma radiation dose rate. The general practice of this programme is to observe the outdoor gamma radiation levels. This paper summarizes the methodology and gamma radiation levels of four research centres viz. BARC, IGCAR, VECC, RRCAT and an industry BRIT, Vashi

Ambient radioactivity levels and radiation doses. Annual report 2011

International Nuclear Information System (INIS)

Bernhard-Stroel, Claudia; Hachenburger, Claudia; Trugenberger-Schnabel, Angela; Peter, Josef

2013-07-01

The annual report 2011 on ambient radioactivity levels and radiation doses covers the following issues: Part A: Natural environmental radioactivity, artificial radioactivity in the environment, occupational radiation exposure, radiation exposure from medical applications, the handling of radioactive materials and sources of ionizing radiation, non-ionizing radiation. Part B; Current data and their evaluation: Natural environmental radioactivity, artificial radioactivity in the environment, occupational radiation exposure, radiation exposure from medical applications, the handling of radioactive materials and sources of ionizing radiation, non-ionizing radiation. The Appendix includes Explanations of terms, radiation doses and related units, external and internal radiation exposure, stochastic and deterministic radiation effects, genetic radiation effects, induction of malignant neoplasm, risk assessment, physical units and glossary, laws, ordinances, guidelines, recommendations and other regulations concerning radiation protection, list of selected radionuclides.

Natural external radiation level and population dose in Hunan province

International Nuclear Information System (INIS)

1985-01-01

A survey of the natural external radiation level in Hunan Province is reported. The measurements were performed with FD-71 scintillation radiometers. On the basis of measurements at about 1,600 locations, the contribution from cosmic radiation is found to be 3.0 x 10 -8 Gy.h -1 , and the average absorbed dose rates in air from terrestrial γ-radiation for outdoors, indoors and roads are determined to be 9.2, 13.1 and 9.0 x 10 -8 Gy.h -1 , respectively. The γ-radiation indoors is markedly higher than that outdoors by a factor of 1.42. The lowest γ-radiation level is found in the sedimentary plain around Donting Lake, while the highest absorbed dose rates in air from terrestrial radiation are observed in some areas with exposed granites. The indoor γ-radiation in brick houses is markedly higher than that in wooden houses. Tarred roads have evidently lower radiation level than sand-gravel roads or concrete roads. The annual effective dose equivalents to the population from cosmic and terrestrial sources are 0.256 and 0.756 mSv, respectively, with a total value of 1.012 mSv

Low-level radioactive waste disposal: radiation protection laws

International Nuclear Information System (INIS)

Chapuis, A.M.; Guetat, P.; Garbay, H.

1991-01-01

The politics of radioactive waste management is a part of waste management and activity levels are one of the components of potential waste pollutions in order to assume man and environment safety. French regulations about personnel and public' radiation protection defines clearly the conditions of radioactive waste processing, storage, transport and disposal. But below some activity levels definite by radiation protection laws, any administrative procedures or processes can be applied for lack of legal regulations. So regulations context is not actually ready to allow a rational low-level radioactive waste management. 15 refs.; 4 tabs.; 3 figs

Radiation therapy for primary breast lymphoma in male gynecomastia: a rare case report and review of the literature.

Science.gov (United States)

Ishibashi, Naoya; Hata, Masaharu; Mochizuki, Takao; Ogawa, Kogi; Sugiura, Hiroaki; Takekawa, Yoshinori; Maebayashi, Toshiya; Aizawa, Takuya; Sakaguchi, Masakuni; Abe, Osamu

2016-10-01

Primary breast lymphoma is a rare type of non-Hodgkin lymphoma and usually affects women, although a few cases have been reported in men. Chemotherapy and radiation therapy, or a combination of both, are frequently administered for treatment of primary breast lymphoma, as local control by surgical resection is poor. No standard therapy has been established, and the optimal radiation dose and irradiation field for male patients are unknown. The present report describes a 75-year-old man with bilateral cirrhosis-induced gynecomastia who was diagnosed with primary breast lymphoma; specifically, diffuse large B-cell lymphoma. Because of his hepatic dysfunction, he was treated with radiation therapy alone. Radiation therapy was followed by eight cycles of rituximab monotherapy. Clinical response was good, with no signs of relapse. Clinicians may benefit from knowledge regarding effective treatment of primary breast lymphoma in male patients, which has been rarely reported owing to the low incidence of this condition. The outcome in the present case may help to establish effective treatment guidelines in similar cases.

The primary exposure standard for Co-60 gamma radiation: characteristics and measurements procedures

International Nuclear Information System (INIS)

Laitano, R.F.; Toni, M.P.

1983-01-01

A description is given of a cavity ionization chamber used, as a primary exposure standard, at the Laboratorio di Metrologia delle Radiazioni Ionizzanti of the ENEA in Italy. The primary standard is designed to make absolute measurements of exposure due to the Co-60 gamma radiation. The procedures for the realizationof the exposure unit are also described. Finally results of some international comparisons are reported

Effects of low levels of radiation on humans

International Nuclear Information System (INIS)

Auxier, J.A.

1981-01-01

The state of knowledge on effects of low-level ionizing radiations on humans is reviewed. Several problems relating to dose thresholds or lack of thresholds for several types of cancer and high LET radiations and the effects of fractionation and dose protection are discussed

Potential for improved radiation thermometry measurement uncertainty through implementing a primary scale in an industrial laboratory

Science.gov (United States)

Willmott, Jon R.; Lowe, David; Broughton, Mick; White, Ben S.; Machin, Graham

2016-09-01

A primary temperature scale requires realising a unit in terms of its definition. For high temperature radiation thermometry in terms of the International Temperature Scale of 1990 this means extrapolating from the signal measured at the freezing temperature of gold, silver or copper using Planck’s radiation law. The difficulty in doing this means that primary scales above 1000 °C require specialist equipment and careful characterisation in order to achieve the extrapolation with sufficient accuracy. As such, maintenance of the scale at high temperatures is usually only practicable for National Metrology Institutes, and calibration laboratories have to rely on a scale calibrated against transfer standards. At lower temperatures it is practicable for an industrial calibration laboratory to have its own primary temperature scale, which reduces the number of steps between the primary scale and end user. Proposed changes to the SI that will introduce internationally accepted high temperature reference standards might make it practicable to have a primary high temperature scale in a calibration laboratory. In this study such a scale was established by calibrating radiation thermometers directly to high temperature reference standards. The possible reduction in uncertainty to an end user as a result of the reduced calibration chain was evaluated.

Reduction of the pool-top radiation level in HANARO

International Nuclear Information System (INIS)

Lee, Choong-Sung; Park, Sang-Jun; Kim, Heonil; Park, Yong-Chul; Choi, Young-San

1999-01-01

HANARO is an open-tank-in-pool type reactor. Pool water is the only shielding to minimize the pool top radiation level. During the power ascension test of HANARO, the measured pool top radiation level was higher than the design value because some of the activation products in the coolant reached the pool surface. In order to suppress this rising coolant, the hot water layer system (HWL) was designed and installed to maintain l.2 meter-deep hot water layer whose temperature is 5degC higher than that of the underneath pool surface. After the installation of the HWL system, however, the radiation level of the pool-top did not satisfy the design value. The operation modes of the hot water layer system and the other systems in the reactor pool, which had an effect on the formation of the hot water layer, were changed to reduce pool-top radiation level. After the above efforts, the temperature and the radioactivity distribution in the pool was measured to confirm whether this system blocked the rising coolant. The radiation level at the pool-top was significantly reduced below one tenth of that before installing the HWL and satisfied the design value. It was also confirmed by calculation that this hot water layer system would significantly reduce the release of fission gases to the reactor hall and the environment during the hypothetical accident as well. (author)

Radiation therapy for primary carcinoma of the eyelid. Tumor control and visual function

Energy Technology Data Exchange (ETDEWEB)

Hata, M.; Koike, I.; Odagiri, K.; Kasuya, T.; Minagawa, Y.; Kaizu, H.; Mukai, Y.; Inoue, T. [Yokohama City Univ. Graduate School of Medicine, Kanagawa (Japan). Dept. of Radiology; Maegawa, J. [Yokohama City Univ. Graduate School of Medicine, Kanagawa (Japan). Dept. of Plastic and Reconstructive Surgery; Kaneko, A. [Yokohama City Univ. Graduate School of Medicine, Kanagawa (Japan). Dept. of Ophthalmology

2012-12-15

Background and purpose: Surgical excision remains the standard and most reliable curative treatment for eyelid carcinoma, but frequently causes functional and cosmetic impairment of the eyelid. We therefore investigated the efficacy and safety of radiation therapy in eyelid carcinoma. Patients and methods: Twenty-three patients with primary carcinoma of the eyelid underwent radiation therapy. Sebaceous carcinoma was histologically confirmed in 16 patients, squamous cell carcinoma in 6, and basal cell carcinoma in 1. A total dose of 50-66.6 Gy (median, 60 Gy) was delivered to tumor sites in 18-37 fractions (median, 30 fractions). Results: All but 3 of the 23 patients had survived at a median follow-up period of 49 months. The overall survival and local progression-free rates were 87% and 93% at 2 years, and 80% and 93% at 5 years, respectively. Although radiation-induced cataracts developed in 3 patients, visual acuity in the other patients was relatively well preserved. There were no other therapy-related toxicities of grade 3 or greater. Conclusion: Radiation therapy is safe and effective for patients with primary carcinoma of the eyelid. It appears to contribute to prolonged survival as a result of good tumor control, and it also facilitates functional and cosmetic preservation of the eyelid. (orig.)

Environmental levels of microwave radiation around a satellite earth station

International Nuclear Information System (INIS)

Joyner, K.H.; Bangay, M.J.

1986-01-01

This paper discusses the background to claims of possible adverse health effects arising from exposure to environmental levels of microwave radiation around satellite earth stations. Results of a recent survey of the environmental levels of microwave radiation around two 32 metre diameter satellite communications antennas owned and operated by the Overseas Telecommunications Commission (OTC) of Australia are presented. From the measurements obtained in this survey it can be concluded that the environmental levels of microwave radiation around the OTC and similar satellite facilities do not pose a health risk to persons in the vicinity

Collimation system for a laboratory of primary and secondary ionizing radiation calibration

International Nuclear Information System (INIS)

Oliveira, S.R.; David, M.G.

2003-01-01

This work is part of a cooperation plan between the LNMRI/IRD and the LCR/UERJ, for the a primary calibration at the IRD and a secondary laboratory at the LCR, both calibrated for mammographic beams which will be part a Calibration National Network. For the mounting of the primary laboratory, the first step was to install two additional collimators in order to guarantee that the beam area over the ionization chamber to satisfy the calibration international standards. So, the collimators were constructed obeying the geometric rules, the first being of conic format and the second of the cylindrical format, therefore avoiding the effects of the scattering radiation on the edges. By using this collimation system it was possible to verify the uniformity of the radiation field incident the ionization chamber to be over 98% of the total area, guaranteeing better precision of the measurement

Induction of genetic instability in ρ53 in primary cultures of normal human urothelium exposed low-dose of gamma radiation

International Nuclear Information System (INIS)

Colucci, S.; Mothersill, C.; Seymour, C.; Harney, J.; Gamble, S.; Arrand, J.

1997-01-01

We have previously shown that primary explant cultures of human urothelium exposed to low doses of gamma radiation subsequently exhibit a high level of stable P53 but it was not clear from those studies whether this protein stabilisation occurred through epigenetic events or as a result of mutation. In these experiments, primary urothelium cultures from five different patients were exposed to 0.5 and 5 Gy γ- radiation from a 60 Cobalt source and allowed to grow for 7- 10 division cycles to allow development of any radiation-induced, non lethal changes in the urothelial cells. C-myc, Bcl-2, and stable P53 protein expression was found to be elevated in cultures following both radiation doses. Following 0.5 Gy exposure, the cultures also developed multiple distinct 'foci' of rapidly-dividing cells which strongly over-expressed P53. These grew on a background of morphologically normal cells. When such foci were selectively analysed for their p53 mutation status by PCR-SSCPE, there was evidence that they contained cells which had developed changes to thr p53 gene post-irradiation. These changes appeared to occur more frequently in focal cells than in cells of normal morphological appearance in the same culture. DNA sequence analysis of the p53 gene in 0.5 Gy-induced foci displayed frame shift mutations in some cases. These results may have mechanistic importance given the controversy regarding low-dose radiation effects and p53-related genomic instability. (authors)

Primary processes in radiation-induced crosslinking of poly(2-phenylbutadiene)

International Nuclear Information System (INIS)

Yamaoka, Hitoshi; Kato, Kazuo; Okamura, Seizo.

1987-01-01

The radiation-induced crosslinking of poly(2-phenylbutadiene)(PPB) in ethylene dichloride solution was studied in vacuum at 303 K. The G value of the crosslinking was estimated to be about 7.2. In order to detect the reaction intermediates under irradiation, optical absorption spectra in rigid matrices and ESR spectra in bulk were measured. The absorption spectra due to radical cation of PPB and due to α,α-disubstituted benzyl cation were observed in butyl chloride glass. ESR spectra owing to polyenyl type radical was found in the irradiated specimens of PPB and Diels-Alder type dimer of 2-phenylbutadiene. The primary processes in radiation-induced crosslinking of PPB were discussed on the basis of the results obtained. (author)

Physiological benefits from low levels of ionizing radiation

International Nuclear Information System (INIS)

Luckey, T.D.

1982-01-01

Extensive literature indicates that minute doses of ionizing radiation benefit animal growth and development, fecundity, health and longevity. Specific improvements appear in neurologic function, growth rate and survival of young, wound healing, immune competence, and resistance to infection, radiation morbidity, and tumor induction and growth. Decreased mortality from these debilitating factors results in increased average life span following exposure to minute doses of ionizing radiation. The above phenomena suggest the possibility that ionizing radiation may be essential for life. Limited data with protozoa suggest that reproduction rates decrease when they are maintained in subambient radiation environments. This may be interpreted to be a radiation deficiency. Evidence must now be obtained to determine whether or not ionizing radiation is essential for growth, development, nutrient utilization, fecundity, health and longevity of higher animals. Whether or not ionizing radiation is found to be essential for these physiologic functions, the evidence reviewed indicates that the optimal amount of this ubiquitous agent is imperceptibly above ambient levels. (author)

Pacemaker Primary Curriculum; Lesson Book Level B.

Science.gov (United States)

Ross, Dorothea M.; Ross, Sheila A.

This lesson book, which is the second in a four-level program for young children with learning difficulties, describes the purpose of and equipment and procedures for teaching lessons in the following subjects areas on the primary grade level: arithmetic, reading, vocabulary, listening, planning, problem solving, social behavior, art, music, and…

Pacemaker Primary Curriculum; Lesson Book Level C.

Science.gov (United States)

Ross, Dorothea M.; Ross, Sheila A.

This lesson book, which is the third in a four-level program for young children with learning difficulties, describes the purpose of and equipment and procedures for teaching lessons in the following subject areas on the primary grade level: arithmetic, reading, vocabulary, spelling, printing, listening, planning, problem solving, social behavior,…

Pacemaker Primary Curriculum; Lesson Book Level D.

Science.gov (United States)

Ross, Dorothea M.; Ross, Sheila A.

This lesson book, which is the last in a four-level program for young children with learning difficulties, describes the purpose of and equipment and procedures for teaching lessons in the following subject areas on the primary level: arithmetic, reading, vocabulary, spelling, printing, listening, planning and problem solving, social behavior,…

A knowledge and awareness level survey of radiation protection among the radiation workers in Henan Province

International Nuclear Information System (INIS)

Cheng, Xiao-jun; Tian, Chong-bin; Zhang, Qin-fu; Liu, Cheng; Ding, Li

2008-01-01

Full text: Objective: To reveal the knowledge and awareness level of radiation protection among radiation workers in Henan province and to explore the methods to improve it. Methods: A questionnaire survey was carried out among 208 radiation workers. Results: The correct rate of the answer to radiation protection knowledge from radiation workers in Henan province is 53.78%. Most of them (88.9%) realized that it is important to protect patients and their companions. They adhere to the principles of justification of medial exposure and optimization of radiation protection and follow the management system of radiation protection. However, a few workers didn't follow the principles strictly. Sometime, during the radio diagnosis and radiotherapy services, the patients and their companions were not well protected from the radiation, and some patients were given unnecessary X-ray examine. Even worse, some workers did not attach importance to the regulations of radiation protection and disobey them frequently. Again, some hospital leaders disregard the regulation of radiation protection and didn't follow the regulation of health surveillance and radiation protection monitoring properly. And those behaviors and attitude, in fact, influence some workers' attitude to radiation protection. Conclusion: The level of radiation protection knowledge and awareness among the radiation workers in Henan province needs to be improved. It is necessary to strengthen radiation protection knowledge by strengthening training, and to improve safety awareness among the radiation staff, and, more important, the hospital leaders as well. (author)

Measurement uncertainty in broadband radiofrequency radiation level measurements

Directory of Open Access Journals (Sweden)

Vulević Branislav D.

2014-01-01

Full Text Available For the evaluation of measurement uncertainty in the measurement of broadband radio frequency radiation, in this paper we propose a new approach based on the experience of the authors of the paper with measurements of radiofrequency electric field levels conducted in residential areas of Belgrade and over 35 municipalities in Serbia. The main objective of the paper is to present practical solutions in the evaluation of broadband measurement uncertainty for the in-situ RF radiation levels. [Projekat Ministarstva nauke Republike Srbije, br. III43009

The analysis of radiation levels for daily supplies made in Korea

Energy Technology Data Exchange (ETDEWEB)

Kim, H.R. [Ulsan National Inst. of Science and Tech., Ulsan (Korea, Republic of)

2014-07-01

The radiation levels were measured and assessed for samples around a living environment such as building materials and industrial products for which civil complaint had been filed to have radioactivity in Korea. The dose rates for more than one hundred samples from the goods in a living environment were compared with those of the background. The sample's radiation level ranged from 0.095 μSv/h to 0.162 μSv/h, which are within the range of the laboratory background level from 0.090 μSv/h to 0.174 μSv/h. It was thought the radiation level of the goods for which the civil complaint was given had not particular difference from the environmental radiation level in Korea in spite of deviations for some samples. (author)

Biological monitors for low levels of ionising radiation

International Nuclear Information System (INIS)

Mohankumar, M.N.; Jeevanram, R.K.

1995-01-01

The biological effects of high doses of ionising radiation are well understood and the methods of measurement of these doses well established. However the effects due to extremely low doses remain by and large uncertain. This is because of the fact that at such low doses no gross symptoms are seen. In fact, at these levels the occurrence of double strand breaks leading to the formation of chromosomal aberrations like dicentrics is rare and chances of mutation due to base damage are negligible. Hence neither chromosomal aberration studies nor mutational assays are useful for detecting doses of the order of a few milligray. Results of exhaustive work done by various laboratories indicate that below 20 mGy the chromosomal aberration technique based on scoring of dicentrics cannot distinguish between a linear or a threshold model. However indirect methods like unscheduled DNA synthesis (UDS) and sister chromatid exchanges (SCEs) appear to be promising for the detection of radiation exposures due to low levels of radiation. This report reviews the available literature on the biological effects of low levels of ionising radiation and highlights the merits and demerits of the various methods employed in the measurement of UDS and SCE. The phenomenon of radio-adaptive response (RAR) and its relation to DNA repair is also discussed. (author)

Biological effects of low-level ionizing and non-ionizing radiation

International Nuclear Information System (INIS)

Upton, A.C.

1986-01-01

Early in this century it was recognized that large doses of ionizing radiation could injure almost any tissue in the body, but small doses were generally thought to be harmless. By the middle of the century however it came to be suspected that even the smallest doses of ionizing radiation to the gonads might increase the risk of hereditary disease in subsequently-conceived offspring. Since then the hypothesis that carcinogenic and teratogenic effects also have no threshold has been adopted for purposes of radiological protection. It is estimated nevertheless that the risks that may be associated with natural background levels of ionizing irradiation are too small to be detectable. Hence validation of such risk estimates will depend on further elucidation of the dose-effect relationships and mechanisms of the effects in question, through studies at higher dose levels. In contrast to the situation with ionizing radiation, exposure to natural background levels of ultraviolet radiation has been implicated definitively in the etiology of skin cancers in fair-skinned individuals. Persons with inherited effects in DNA repair capacity are particularly susceptible. Non-ionizing radiations of other types can also affect health at high dose levels, but whether they can cause injury at low levels of exposure is not known

Environmental radiation levels in and around Kalpakkam during 1983-1987

International Nuclear Information System (INIS)

Nambi, K.S.V.; Mehta, N.K.; Sundaram, Meenakshi; Viswambharan, K.R.

1989-01-01

Results of the environmental radiation monitoring around the Kalpakkam Atomic Power Station carried out routinely on quarterly integrating cycles using thermoluminescent dosimeters, are presented and analysed, for the five year period 1983-87. As the first reactor attained criticality in July 1983 and the second unit in August 1985 the results are compared with the previously published values for the period 1980-82. Only at two locations viz. the Micro-met laboratory situated at 800 meters from the station and the main gate located at the 1.6 km exclusion zone boundary, a possible indication of increases in the environmental radiation level associated with the power reactor operations could be discerned. However these were found to be statistically insignificant. The whole terrain is characterised by somewhat high levels of terrestrial radiations with quite wide temporal fluctuations which easily mask the small increases if any in the radiation levels, contributed by the reactors. Places located farther away from the power station and away from the monazite-bearing beaches, yielded an annual average background level of 117 ± 29 mR as against the value of 125 ± 24 mR obtained during the preoperational period of 1980-82. A declining general trend in the radiation levels is seen at many locations and this is thought to be associated with significant reduction in the 137 Cs fallout component of the environmental radiation. (author). 5 refs., 2 tabs., 11 figs

Radiation levels in nuclear diagnostic examinations

International Nuclear Information System (INIS)

Vermeulen, A.M.T.I.

1987-01-01

To estimate the risks for a pregnant radiological worker, radiation level measurements are executed for common nuclear diagnostic techniques. These measurements are combined with the time which the radiologic worker is present during the performance of the diagnostic techniques. It is concluded that a radiologic worker is receiving less than 5 mSv during pregnancy. This is the case with in vivo determination in a department of nuclear medicine with common diagnostic techniques. Reduction of radiation doses during pregnancy is possible by reduction of heart function examinations, skeletal examinations and brain scans. 1 figure; 13 tabs

Somatic and genetic effects of low-level radiation

International Nuclear Information System (INIS)

Upton, A.C.

1974-01-01

Although the biological effects of ionizing radiation are probably better known than those of any other physical or chemical agent in the environment, our information about such effects has come from observations at doses and dose rates which are orders of magnitude higher than natural background environmental radiation levels. Whether, therefore biological effects occur in response to such low levels can be estimated only by extrapolation, based on assumptions about the dose-effect relationship and the mechanisms of the effects in question. Present knowledge suggests the possibility that several types of biological effects may result from low-level irradiation. The induction of heritable genetic changes in germ cells and carcinogenic changes in somatic cells are considered to be the most important from the standpoint of their potential threat to health. On the basis of existing data, it is possible to make only tentative upper limit estimates of the risks of these effects at low doses. The estimates imply that the frequency of such effects attributable to exposure at natural background radiation levels would constitute only a small fraction of their natural incidence. 148 references

Variation in U.V. primary fluorescence-intensity of vital cells depending on 60Co γ-radiation dose

International Nuclear Information System (INIS)

Merkle, K.

1978-01-01

Using impulse-cytofluorophotometry in the ultra-violet spectral region it has been shown on vital, unstained Ehrlich ascites tumour cells that the primary fluorescence intensity of this tumour was on day 11 after transplantation 20 per cent higher than on day 8. Storage of the vital cells for 25 min at 20 0 C had no effect on this result. When the cells were exposed to 60 Co γ-radiation on day 6, a new stable fluorescence level was established after 20 hours. Measurements of the primary fluorescence intensity depending on dose have shown a significant rise starting from 75 rad at 48 hours after irradiation. The fluorescence intensity rose by 42.5 per cent of the control value at 3000 rad, but only by 31.5 per cent on exposure to 4000 rad. (author)

Radiation amorphization of materials

International Nuclear Information System (INIS)

Neklyudov, I.M.; Chernyaeva, T.P.

1993-01-01

The results of experimental and theoretical research on radiation amorphization are presented in this analytical review. Mechanism and driving forces of radiation amorphization are described, kinetic and thermodynamic conditions of amorphization are formulated. Compositional criteria of radiation amorphization are presented, that allow to predict irradiation behaviour of materials, their tendency to radiation amorphization. Mechanism of transition from crystalline state to amorphous state are considered depending on dose, temperature, structure of primary radiation damage and flux level. (author). 134 refs., 4 tab., 25 fig

Quality of Life of Patients with Spinal Metastasis from Cancer of Unknown Primary Origin: A Longitudinal Study of Surgical Management Combined with Postoperative Radiation Therapy.

Science.gov (United States)

Ma, Yifei; He, Shaohui; Liu, Tielong; Yang, Xinghai; Zhao, Jian; Yu, Hongyu; Feng, Jiaojiao; Xu, Wei; Xiao, Jianru

2017-10-04

Patients with spinal metastasis from cancer of unknown primary origin have limited life expectancy and poor quality of life. Surgery and radiation therapy remain the main treatment options, but, to our knowledge, there are limited data concerning quality-of-life improvement after surgery and radiation therapy and even fewer data on whether surgical intervention would affect quality of life. Patients were enrolled between January 2009 and January 2014 at the Changzheng Hospital, Shanghai, People's Republic of China. The quality of life of 2 patient groups (one group that underwent surgery followed by postoperative radiation therapy and one group that underwent radiation therapy only) was assessed by the Functional Assessment of Cancer Therapy-General (FACT-G) questionnaire during a 6-month period. A subgroup analysis of quality of life was performed to compare different surgical strategies in the surgical group. A total of 287 patients, including 191 patients in the group that underwent surgery and 96 patients in the group that underwent radiation therapy only, were enrolled in the prospective study; 177 patients completed all 5 checkpoints and 110 patients had died by the final checkpoint. The surgery group had significantly higher adjusted quality-of-life scores than the radiation therapy group in each domain of the FACT-G questionnaire (all p quality of life in patients with spinal metastasis from cancer of unknown primary origin in the 6-month assessment. In terms of surgical strategies, circumferential decompression seems better than laminectomy alone in quality-of-life improvement. Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Effectiveness of counseling at primary health facilities: Level of ...

African Journals Online (AJOL)

Effectiveness of counseling at primary health facilities: Level of knowledge of antenatal attendee and their ... Objectives: To determine the effectiveness of counseling on HIV done in primary health facilities ... AJOL African Journals Online.

Risks of low-level radiation - the evidence of epidemiology

International Nuclear Information System (INIS)

Gloag, D.

1980-01-01

The difficulties involved in estimating risks from very low levels of radiation and the use of dose-response models for cancer incidence are discussed with reference to the third BEIR Committee report on the Effects on Populations of Exposure to low levels of Ionizing Radiation (1980). Cancer risk estimates derived from different epidemiological studies are reviewed. They include atom bomb survivors, medically irradiated groups and occupational groups. (36 references). (author)

Human exposure to low level ionising radiation

International Nuclear Information System (INIS)

Paix, David

1988-01-01

This paper describes the low-level radiation sources and their effects on human populations, from a global perspective. 'Low-level' means exposures in the range of the natural background to which everybody is exposed. The quoted values are whole-world averages, but individual variations are mentioned in a few cases. (author). 22 refs

Development of a parallel plate ion chamber for radiation protection level

International Nuclear Information System (INIS)

Bottaro, Marcio; Landi, Mauricio; Moralles, Mauricio

2011-01-01

A new parallel plate vented ion chamber is proposed in this paper. The application of this chamber was primarily intended to the measurement of stray radiation in interventional procedures, but the energy response of about 2.6%, which was obtained in the first prototype, on the range from 40 to 150 kV using ISO 4037-1 narrow qualities, provided the possibility of a wide modality application on radiation protection. Primary studies with Maxwell 2D electromagnetic field simulator revealed an optimized model regarding effective volume and saturation voltage levels, which conferred to the ion chamber a dual entrance window feature. The development of this ion chamber has the main contribution of Monte Carlo calculations as a support tool to the establishment of the effective volume of the chamber and determination of the best materials for housing mounting and conductive elements, such as guard rings, electrode, and windows. Even the composition of the conductive layers, which would be neglected due to their very small thicknesses (about 35 μm), had important influence on the results and could be better understood with Monte Carlo N-Particle Transport Code System (MCNP) simulations. (author)

Evaluating natural radiation level by existing airborne radioactive data

International Nuclear Information System (INIS)

Mingkao, Hu; Changqing, Han; Jiangqi, Fang; Zhengxin, Shen

2002-01-01

Airborne Survey and Remote Sensing Center of Nuclear Industry, founded in the middle of 1950s, is a unique unit specialized in uranium exploration by airborne radioactive survey in China. Large numbers of airborne data of radioactivity and abundant experience have been accumulated for more than 40 years. All-round detailed investigation of environmental radiation levels in our country will not be completed in the near future. Thus, at present it is considered to evaluate natural radiation levels using the existing radioactive data. This paper introduces the results of analysis and study comparing airborne radioactive data for radiation environmental evaluation obtained from survey area in Gansu, China, in the 2001 with the measurement results by ground gamma ray radiation dose-rate instrument for environment. The air-earth inter-comparison error does not exceed 30% at radiation fields with a definite area, and the air-earth inter-comparison error does not exceed 60% at outcrop of granite. In 6km long profile that has various circumstances, such as desert, Gobi, farmland and residential area, minimum of air absorbed dose rate is 47nGy/h at an altitude of 1 meter above the soil plane, maximum is 68nGy/h. The inter-comparison errors are usually less than 20%, and maximum is 25.38%. This shows that it is feasible to obtain natural radiation levels rapidly if we could use the existing radioactive data adequately and make some correction, such as geology factor

Review of the controversy on risks from low levels of radiation

International Nuclear Information System (INIS)

Higson, D.

2001-01-01

The need for regulation of low levels of radiation exposure, and the estimation of risks from such exposures, are based on the assumption that risk is proportional to dose without a threshold, the 'linear no-threshold (LNT) hypothesis'. This assumption is not supported by scientific data. There is no clear evidence of harm from low levels of exposure, up to at least 20 mSv (acute dose) or total dose rates of at least 50 mSv per year. Even allowing for reasonable extrapolation from radiation levels at which harmful effects have been observed, the LNT assumption should not be used to estimate risks from doses less than 100 mSv. Laboratory and epidemiological evidence, and evolutionary expectations of biological effects from low level radiation, suggest that beneficial health effects (sometimes called 'radiation hormesis') are at least as likely as harmful effects from such exposures. Controversy on this matter strikes at the basis of radiation protection practice

Primary radiation therapy for early breast cancer: the experience at the joint center for radiation therapy

International Nuclear Information System (INIS)

Harris, J.R.; Botnick, L.; Bloomer, W.D.; Chaffey, J.T.; Hellman, S.

1981-01-01

The results of primary radiation therapy in 176 consecutive patients with clinical State I and II carcinoma of the breast were reviewed. Median follow-up time was 47 months. The overall breast relapse rate was 7%. Patients undergoing interstitial implantation had a significantly lower breast relapse rate (1%) than patients not undergoing implantation (11%). Breast relapse was more common in patients undergoing incisional or needle biopsy (17%), compared to patients treated after excisional biopsy (5%). In patients undergoing excisional biopsy, but not interstitial implantation, breast relapse was related to external beam dose. Twelve percent of the patients who received less than 1600 ret dose relapsed in the breast, compared to none of the 19 patients who received more than 1700 ret dose. These results imply that supplemental irradiation to the primary tumor area is required following excisional biopsy of a primary breast cancer when 4500-5000 rad is delivered to the entire breast

Cosmic radiation doses at flight level altitudes of airliners

International Nuclear Information System (INIS)

Viragh, E.; Petr, I.

1985-01-01

Changes are discussed in flux density of cosmic radiation particles with time as are the origin of cosmic radiation, the level of cosmic radiation near the Earth's surface, and the determination of cosmic radiation doses in airliners. Doses and dose rates are given measured on different flight routes. In spite of the fact that the flight duration at an altitude of about 10 km makes for about 80% of the total flight time, the overall radiation burden of the crews at 1000 flight hours a year is roughly double that of the rest of the population. (J.C.)

Biological monitors for low levels of ionising radiation

Energy Technology Data Exchange (ETDEWEB)

Mohankumar, M N; Jeevanram, R K [Safety Research and Health Physics Group, Indira Gandhi Centre for Atomic Research, Kalpakkam (India)

1996-12-31

The biological effects of high doses of ionising radiation are well understood and the methods of measurement of these doses well established. However the effects due to extremely low doses remain by and large uncertain. This is because of the fact that at such low doses no gross symptoms are seen. In fact, at these levels the occurrence of double strand breaks leading to the formation of chromosomal aberrations like dicentrics is rare and chances of mutation due to base damage are negligible. Hence neither chromosomal aberration studies nor mutational assays are useful for detecting doses of the order of a few milligray. Results of exhaustive work done by various laboratories indicate that below 20 mGy the chromosomal aberration technique based on scoring of dicentrics cannot distinguish between a linear or a threshold model. However indirect methods like unscheduled DNA synthesis (UDS) and sister chromatid exchanges (SCEs) appear to be promising for the detection of radiation exposures due to low levels of radiation. This report reviews the available literature on the biological effects of low levels of ionising radiation and highlights the merits and demerits of the various methods employed in the measurement of UDS and SCE. The phenomenon of radio-adaptive response (RAR) and its relation to DNA repair is also discussed. (author). 98 refs., 11 figs., 4 tabs.

Investigation of the Work Motivation Levels of Primary School Teachers

Science.gov (United States)

Ates, Hatice Kadioglu; Yilmaz, Perihan

2018-01-01

This study was conducted to examine the work motivation levels of primary school teachers working in primary school institutions located in Istanbul province, Kucukcekmece district. The descriptive survey model was used in this study. The population of the study consists of primary school teachers and primary school administrators working in state…

Low-level radiation and cancer deaths

International Nuclear Information System (INIS)

Sanders, B.S.

1978-01-01

It is stated that although the proportion of cancer deaths among males is somewhat higher for Hanford employees with recorded occupational radiation exposure compared with males in the general population of the State of Washington, there is no indication that radiation is the cause of this difference. Statistics are given for mean doses received and for deaths from cancer and other causes for male employees. It is shown that for each year the mean dose level of those who died from cancer is not significantly different from the mean of those who died from other causes. The mean dose level for the majority of those who died in a specific year is lower than the mean for the survivors in the year of death, in the year preceding the year of death, or in the two years preceding the year of death. This is true whether the mean was for those dying from cancer or from other causes. These relationships are similar for female exposed employees and agree with other similar studies. The latest analysis on longevity of exposed male Hanford employees vs those nonexposed and the out-of-plant controls from date of hire to April 1974 are considered and show no firm indication of any lasting adverse health effects among employees attributable to occupational exposure to radiation within permissible limits. (U.K.)

Legislation and litigation related to low-level radiation injury claims

International Nuclear Information System (INIS)

McCraw, T.

1985-01-01

Current legislation and litigation related to radiation exposure will have an enormous impact on the radiation protection and monitoring requirements of the future. A brief review of some proposed injury compensation bills for veterans and a recent court decision for low-level radiation injury claims are reviewed

The Radiation Levels for Household Goods Made in Korea

International Nuclear Information System (INIS)

Kim, Hee Reyoung; Park, Doo Won; Lee, Wan No; Choi, Sang Do; Chung, Kun Ho; Kang, Mun Ja; Choi, Geun Sik; Lee, Chang Woo

2008-01-01

The environmental radiation based on a natural and artificial radiation always exists in the environment. The natural radiation includes cosmic ray coming into the atmosphere from outer space, radiation emitted from the earth's crust or soil, radiation by the radon in the air and its progenies. These natural radiation comes from various buildings like a house and an apartment, agricultural and stock breeding products like rice and milk, and a body, etc. The artificial radiation emanates from a nuclear power plant, a radioisotope facility, a radioactive waste disposal site, a medical or research facility treating a radioactive material, a radiation generation device for an industry, TV, a microwave oven, appliances like a fluorescent clock, an airport security table, etc. Among the various kinds of radioactive nuclides that existed in the earth's crust at the time of the earth's formation about 4,000 million years ago, all the short half life nuclides decayed and the long half life nuclides remain amid the nuclides of a half life with more than 100 million years and their progenies now. In fact, the natural radiation level is determined by the nuclides of the Thorium series which have K-40 (half life 1.25 billion years), Th-232 (half life 14.5 billion years) as a parent nuclide, the nuclides of the uranium series which have U-238 (half life 4.5 billon years) as a parent nuclide, and the cosmic ray like photon and muon. These nuclides are distributed in the soil, sea water, construction material and body with different concentrations. Different radiation dose rates are presented in different regions due to the different concentrations of the radioactive minerals included at the materials. Actually, Brazil and India reveal a relatively high natural radiation level

Studies on the natural radiation levels around the Caspian sea area

International Nuclear Information System (INIS)

Akbari, R.B.

1993-01-01

We measured about 80 items from four areas of Mazandaran, randomly selected samples of food products, soil and water, around the shore of the Caspian sea area. The results showed that the natural radioactivity in beans and broad beans in some areas is much more than in others. The results were also compared with the levels of radiations from some materials from Brazil, which also contained high levels of radiations. Samples measured in this study showed higher levels of radiations than the American food products. (author). 12 refs, 8 tabs

Radiation Treatment for Primary Adenocarcinoma of Bartholin Gland- A Case Report and Review of Literature

International Nuclear Information System (INIS)

Oh, Won Yong; Whang, In Soon

1989-01-01

A patient with primary adenocarcinoma of Bartholin gland is reported and the literatures relevant to this disease reviewed. Not only this disease is very rare but also primary carcinomas of Bartholin gland are misdiagnosed as cysts or abscesses in half of the cases, leading to considerable delay in diagnosis. And so, It was wasted long time before definitive therapy. However, because of a different clinical behavior, cancer of the Bartholin gland should be distinguished from other vulvar carcinomas. Histologically, squamous cell carcinoma and adenocarcinoma are the most common. Virtually all histologic types of Bartholin gland carcinoma metastasize to lymph node, bone, lung and liver in distant sites. The authors data and a review of the literature support the concept that radical vulvectomy with or without bilateral inguina1-femoral lymphadenectomy is required. On the other hand, except primary radiation treatment for small or medium sized cancers, the results obtained by radiation therapy in carcinoma of the vulva including Bartholin gland are generally discouraging. A role for postoperative adjuvant radiation therapy suggests because of high incidence of positive inguinal-femoral lymph nodes. In the near time, natural history and biological behavior of Bartholin gland cancer must be disclosed in detail. And also optimal treatment modality and prognostic factors shall be determine

Level of Radiofrequency (RF) Radiations from GSM Base Stations ...

African Journals Online (AJOL)

Levels of radiofrequency radiations around two global systems for mobile communication (GSM) base stations located in the vicinity of a residential quarter and workplace complex were measured. The effects of the radiofrequency radiations on albino mice placed in exposure cages and located around the base stations ...

Investigation of the relationship between knowledge concerning radiation and the level of anxiety toward radiation in student nurses

International Nuclear Information System (INIS)

Kunugita, Naoki

2008-01-01

In the medical fields, the use of radiation is indispensable in diagnosis, radiotherapy, nuclear medicine and various other areas. On the other hand, great anxiety is often felt due to the misunderstanding of radiation, and this anxiety is seen in not only patients but also nurses. In this study, a questionnaire survey about knowledge of radiation and the level of anxiety was carried out in student nurses for three years from 2005 to 2007. The questionnaire included the level of anxiety about radiation and 12 basic question items concerning radiation. The results showed that the student with poor knowledge about radiation showed high anxiety. After a series of lectures concerning radiation, the acquisition of knowledge and a decrease in anxiety were observed in the students. However, it was still shown that people with scarce knowledge concerning radiation still had high anxiety at the end of the lectures. In conclusion, it was shown that education about radiation is necessary to decrease anxiety about radiation among nurses in medical care. (author)

Learning About Bird Species on the Primary Level

Science.gov (United States)

Randler, Christoph

2009-04-01

Animal species identification is often emphasized as a basic prerequisite for an understanding of ecology because ecological interactions are based on interactions between species at least as it is taught on the school level. Therefore, training identification skills or using identification books seems a worthwhile task in biology education, and should already start on the primary level. On the primary level, however, complex interactions could not be taught but pupils are often interested in basic knowledge about species. We developed a hands-on, group-based and self-determined learning phase organized in workstations. About 138 pupils (2nd-4th graders) participated in this study. The two groups received an identification treatment with six different bird species. These were presented either as soft toys or as taxidermy specimen. Both groups scored similar prior and after the treatment (posttest 1) and with a delay of 6-8 weeks (posttest 2). More complex general linear modeling revealed a significant influence of prior knowledge, treatment and of grade (2nd, 3rd or 4th grade) on the first posttest while in the retention test gender differences emerged. We suggest that soft toys may be of equal value for teaching species identification on the primary level compared to natural taxidermic specimen, especially when considering pricing, insensitivity to handling, and contamination with agents used for preservation.

Does elimination of planned postoperative radiation to the primary bed in p16-positive, transorally-resected oropharyngeal carcinoma associate with poorer outcomes?

Science.gov (United States)

Sinha, Parul; Pipkorn, Patrik; Thorstad, Wade L; Gay, Hiram A; Haughey, Bruce H

2016-10-01

The purpose of our study is to compare oncologic and functional outcomes of p16-positive oropharyngeal squamous cell carcinoma (OPSCC) patients, in the presence and absence of planned radiation to the primary bed following transoral surgery (TOS), stratified by T-classification. Retrospective cohort study of 261, T1-T4, consecutively TOS-treated OPSCC patients. At a median follow-up of 61months, local recurrence (LR) occurred in 6 (2.3%)patients (3 each in T1-T2 and T3-T4 groups), of which 5 had tumors in the tongue base and one in the tonsil. Of patients not receiving planned primary bed radiation, LR occurred in 3% of T1-T2s versus 17% of T3-T4s. In patients with T1-T2 tumors, Absolute Risk Reduction of LR with primary bed radiation was 3.26% (95% CI: -0.37%, 7%); Number Needed to Treat to prevent one LR was 31 (95% CI: 14.5, 271). Absolute Risk Increase for gastrostomy-tube with primary bed radiation was 34.4% (95% CI: 24%, 45%); Number Needed to Harm was 3 (95% CI: 2.2, 4.2), i.e., for every three patients with T1-T2 tumors receiving primary bed radiation, one had a gastrostomy-tube. Elimination of primary bed radiation in margin-negative resected, T1-T2 p16-positive OPSCC was not associated with significant compromise of local control, and correlated with superior swallowing preservation, assessed using gastrostomy rate as a surrogate. Lack of primary bed radiation in T3-T4 tumors associated with significantly increased LR rates. Copyright © 2016 Elsevier Ltd. All rights reserved.

Level Densities and Radiative Strength Functions in 170,171Yb

International Nuclear Information System (INIS)

Agvaanluvsan, U.; Schiller, A.; Becker, J.A.; Berstein, L.A.; Guttormsen, M.; Mitchell, G.E.; Rekstad, J.; Siem, S.; Voinov, A.

2003-01-01

Level densities and radiative strength functions in 171 Yb and 170 Yb nuclei have been measured with the 171 Yb( 3 He, 3 He(prime) γ) 171 Yb and 171 Yb( 3 He, αγ) 170 Yb reactions. A simultaneous determination of the nuclear level density and the radiative strength function was made. The present data adds to and is consistent with previous results for several other rare earth nuclei. The method will be briefly reviewed and the result from the analysis will be presented. The radiative strength function for 171 Yb is compared to previously published work.

Monte-Carlo study on primary knock-on atom energy spectrum produced by neutron radiation

International Nuclear Information System (INIS)

Zhou Wei; Liu Yongkang; Deng Yongjun; Ma Jimin

2012-01-01

Computational method on energy distribution of primary knock-on atom (PKA) produced by neutron radiation was built in the paper. Based on the DBCN card in MCNP, reaction position, reaction type and energy transfer between neutrons and atoms were recorded. According to statistic of these data, energy and space distributions of PKAs were obtained. The method resolves preferably randomicity of random number and efficiency of random sampling computation. The results show small statistical fluctuation and well statistical. Three-dimensional figure of energy and space distribution of PKAs were obtained, which would be important to evaluate radiation capability of materials and study radiation damage by neutrons. (authors)

Some Comparisons of Measured and Predicted Primary Radiation Levels in the Aagesta Power Plant

Energy Technology Data Exchange (ETDEWEB)

Aalto, E; Sandlin, R; Krell, Aa

1968-05-15

Neutron fluxes and gamma exposure rates in the primary shields of the Aagesta nuclear plant have been measured and the results compared with values predicted during shield design, and with values obtained later by the NRN bulk shielding code. The input data for the problems are given. The radial predictions are conservative by a factor of not more than 2 close to the reactor and by an unknown, higher factor further out. The conservatism is explainable by the differences between the true local conditions and core power distributions and those assumed in the predictions. The axial flux levels based on streaming calculations are found to agree quite well with the estimated values. The conservatism here is not so large and it seems to be necessary to be very careful when handling streaming problems. The experience gained shows that a power plant is less suitable for studying the accuracy of the shield design codes as such, but the practical results from the combined application of massive shield codes and void streaming predictions to complicated problems give information about the true degree of conservatism present.

Terrestrial radiation level in selected asphalt plants in Port Harcourt ...

African Journals Online (AJOL)

Terrestrial radiation level in selected asphalt plants in Port Harcourt, Nigeria. ... An environmental radiation survey in asphalt processing plants in Rivers State was been carried out ... Therefore the results show significant radiological risk.

Epidemiological studies in the high and normal level radiation areas of Kerala

International Nuclear Information System (INIS)

Koya, P.K.M.

2012-01-01

High and normal level natural radiation areas of Kerala give unique opportunities to estimate the risk, if any, of chronic low dose exposure by direct epidemiological studies on human beings. Studies in the area are being carried out by Low Level Radiation Research Laboratory of Bhabha Atomic Research Centre in collaboration with Departments of Health and Family Welfare/Social Welfare of the Government of Kerala and local post graduate colleges. To assess the role of chronic low dose exposure in the induction/transmission of chromosomal alterations across generations, hospital based cytogenetic studies on newborns was carried out to estimate and compare the frequency of chromosomal aberrations and karyotypes anomalies in the high (areas with radiation dose of more than 1.50 mGy/year) and normal (areas with radiation dose of 1.50 mR/year or less) level radiation areas. A total of 1,267,788 metaphases from 27,295 (9,64,390 cells from 17,298 newborns of high and 3,03,398 cells from 9,997 newborns of normal level radiation areas) newborns was screened

Radiation levels from computer monitor screens within Benue State ...

African Journals Online (AJOL)

Investigation of possible presence of soft X-ray levels from Computer Screens at distances of 0.5m and 1.0m was carried out within Benue State University, Makurdi, using ten different monitor models. Radiation measurement was carried out using a portable digital radiation meter, INSPECTOR 06250 (SE international Inc.

Significance of serum endostatin levels in patients with primary lung cancer

International Nuclear Information System (INIS)

Peng Qunxin; Ling Chunhua; Ji Cheng

2005-01-01

Objective: To investigate the relationship between the serum level of endostatin and the clinical pathophysiological characteristics in patients with primary lung cancer. Methods: The serum levels of endostatin were detected in 48 patients with primary lung cancer and 50 patients with benign pulmonary diseases by enzyme-linked immunosorbent assay (ELISA) method. Results: Serum endostatin level in patients with primary lung cancer was significantly higher than it in patients with benign pulmonary diseases (P<0.01). It was higher in adenocarcinoma group than that in squamous cell carcinoma and small cell carcinoma group (P<0.05). The level of serum endostatin in lung cancer with TNM stage III + IV was higher than that in patients in stage I + II (P<0.01). And it was also higher in patients suffering from lung cancer with metastasis than that in patients with no metastasis (P<0.05). However, there was not a significant relation between serum endostatin level the location of the tumor and lymph node metastasis. Conclusion: Serum endostatin level in expressed higher in patients with primary lung cancer. There is significant relationship between serum endostatin level, histological classification, TNM stage and metastasis of lung cancer. (authors)

Low level ionizing radiation and human mortality: multi-regional epidemiological studies

International Nuclear Information System (INIS)

Hickey, R.J.; Bowers, E.J.; Spence, D.E.; Zemel, B.S.; Clelland, A.B.; Clelland, R.C.

1981-01-01

Analyses of relationships involving environmental chemicals, background radiation, and mortality rates for diseases of the heart and several cancer categories are presented. Bivariate correlation coefficients between radiation and mortality rate were significantly negative for cancer of the lung and respiratory organs, cancer of the buccal cavity and pharynx, cancer of the digestive organs and peritoneum, total cancer and diseases of the heart. Only the correlation coefficient between background radiation and leukemia-aleukemia was positive, and that not significantly positive. Initial multivariate statistical studies support the bivariate results in that all significant regression terms that represent background radiation have been negative. Background radiation level was not a significant predictor for leukemia-aleukemia mortality rate when examined without regard to age. This preliminary work suggests that any health effects of background radiation on the diseases studied do not exceed in magnitude those of environmental chemicals. It also suggests that models implying important long-term deleterious effects of low levels of ionizing radiation on humans may be invalid. (author)

Examining a link between SPEs and ground level radiation

Science.gov (United States)

Overholt, Andrew

2015-01-01

Researchers have previously found a correlation between solar proton events (SPEs) and congenital malformations (CMs). A similar correlation has also been found between long term solar variability and CMs. We examine the ionizing radiation dose from these events as well as the largest events on record to determine whether these events are capable of producing these effects. We show that the total ionizing radiation dose (consisting of neutrons and muons) at ground level is insufficient for production of the observed increases in CM rate under the current paradigm regarding ionizing radiation from muons and neutrons. Current research on the subject shows that our assumptions regarding muonic ionizing radiation may be underestimating their biologic effect. We recommend further experimentation regarding the radiation dose due to muons, as this may prove to be a more substantial contribution to our radiation environment than previously assumed.

Health effects of low-level radiation in shipyard workers

International Nuclear Information System (INIS)

Matanoski, G.M.

1991-06-01

The Nuclear Shipyard Workers Study (NSWS) was designed to determine whether there is an excess risk of leukemia or other cancers associated with exposure to low levels of gamma radiation. The study compares the mortality experience of shipyard workers who qualified to work in radiation areas to the mortality of similar workers who hold the same types of jobs but who are not authorized to work in radiation areas. The population consists of workers from six government and two private shipyards

Identification of entry-level competencies for associate degree radiographers as perceived by primary role definers

International Nuclear Information System (INIS)

Thorpe, R.L.

1981-01-01

The primary purpose of this study was to identify those competencies needed by Associate Degree Radiographers when they assume employment as entry-level practitioners. A second purpose of the study was to rank order the identified competencies within the role delineations recognized by the Essentials and Guidelines of an Accredited Educational Program for the Radiographer. These role delineations include: radiation protection, exercise discretion and judgment, emergency and life saving techniques, patient care and interpersonal communication, and role as professional member. A third purpose of the study was to examine the degree of consensus on role definition of entry-level competencies needed by Associate Degree Radiographers as perceived by primary role definers (such as employers, employees, and educators), and by other selected variables: age, sex, length of experience in radiologic technology, level of formal education, and place of employment. A major finding of this study was that respondents did not differ significantly in their ranking of entry-level competencies needed by Associate Degree Radiographers when the responses were analyzed according to position, age, sex, length of experience, level of education, or place of employment. Another important finding was that respondents considered all of the 63 competencies as important and needed by Associate Degree Radiographers upon initial employment.A major conclusion and recommendation of this study, in view of the high agreement on the rank ordering of competencies, was that these competencies should be included in a competency-based education model. It was further recommended that a three-way system of communication between employers, employees, and educators be considered in order to pool resources and to increase understanding of each position group's contribution and influence on entry-level Associate Degree Radiographers

Hormesis with ionizing radiation

International Nuclear Information System (INIS)

Luckey, T.D.

1982-01-01

This article reviews a book which summarizes and classifies more than 1250 references to experimental work with low-level radiation between 1898 and 1977; explains that the detailed material is presented in tabular form with type of radiation as the primary classification and type of organism and date of report as subclassifications; notes that an incredible variety of effects are specified for flora and fauna; praises the summaries of background radiation and of overall radiation-dose effects to a variety of organisms; and emphasizes the importance of information dealing with the public perception of radiation and its effects

Evaluation of radiation protection educational level of professional exposed workers

International Nuclear Information System (INIS)

Marinkovic, O.; Krstev, S.; Jovanovic, S.

2006-01-01

Full text: Serbia and Montenegro legislation concerning with radiation protection was upgrading after publication ICRP- 60 and B.S.S., No.115. Present Law on the Protection against Ionizing Radiation is in force from 1996. Among quite new issues in radiation protection regulations there was article relate to obligatory refresher training. Due to adverse political and economic situation through many years radiation protection regulations were not fulfill completely. The aim of this investigation was to get real view to education level of professional exposed workers. In Serbia and Montenegro the most of ionizing radiation sources are in medical use and the most exposed workers are radiographers and radiologists. The test was passed by 200 radiographers and 50 radiologists. Main groups of questions were: Radiation protection and safety; difference between safety and security; legislation: law and regulations; incidents, accidents and operational failures: recording, learning. Usually, knowledge from school pales. New quantities (as ambient and personal dose equivalent) are mostly unknown. It is easier to understand the real difference between safety and security than to understand linguistic differences. Discussing regulations workers are more interesting in syndicate regulations than radiation protection ones. Operational failures and incidents are hidden. Better to say: nobody dare to speak about them. The results imposed conclusion that regulatory body has to pay more attention to upraise safety culture and radiation protection education level of professional exposed workers. (authors)

Predictive analysis of the radiation exposure for the primary cooling system of the rated power operation of MONJU

International Nuclear Information System (INIS)

Matuo, Youichirou; Miyahara, Shinya; Hasegawa, Masanori; Maegawa, Yoshiharu

2011-01-01

Radioactive corrosion products (CP) are main source of personal radiation exposure during maintenance without fuel-failure accident in the Liquid-Metal Fast Breeder Reactor (LMFBR) plants. In order to establish the techniques of radiation dose estimation for personnel, program system 'DORE' has been developed. The DORE system is constructed by PSYCHE code and QAD code system. The density of each deposited CP of primary coolant system in MONJU was estimated by using the PSYCHE. Moreover, the QAD-CGGP2R code is applied to dose rate calculations for the primary coolant system in MONJU. The dose rate around primary piping system was visualized using AVS software. The predicted values were estimated to be saturated at 2-3 mSv/h in twenty years after the start of operation, and the dose rate reaches 4 mSv/h in domains near the IHX and the cold-leg piping. It has been assumed that the main radiation source is 54 Mn in the IHX, primary pump and cold-leg piping region. On the other hand, it was indicated that the contribution to dose rate of the 60 Co accounted for approximately 23% in the hot-leg piping region. (author)

Sacral chordomas: Impact of high-dose proton/photon-beam radiation therapy combined with or without surgery for primary versus recurrent tumor

International Nuclear Information System (INIS)

Park, Lily; De Laney, Thomas F.; Liebsch, Norbert J.; Hornicek, Francis J.; Goldberg, Saveli; Mankin, Henry; Rosenberg, Andrew E.; Rosenthal, Daniel I.; Suit, Herman D.

2006-01-01

Purpose: To assess the efficacy of definitive treatment of sacral chordoma by high-dose proton/photon-beam radiation therapy alone or combined with surgery. Methods and Materials: The records of 16 primary and 11 recurrent sacral chordoma patients treated from November 1982 to November 2002 by proton/photon radiation therapy alone (6 patients) or combined with surgery (21 patients) have been analyzed for local control, survival, and treatment-related morbidity. The outcome analysis is based on follow-up information as of 2005. Results: Outcome results show a large difference in local failure rate between patients treated for primary and recurrent chordomas. Local control results by surgery and radiation were 12/14 vs. 1/7 for primary and recurrent lesions. For margin-positive patients, local control results were 10 of 11 and 0 of 5 in the primary and recurrent groups, respectively; the mean follow-up on these locally controlled patients was 8.8 years (4 at 10.3, 12.8, 17, and 21 years). Radiation alone was used in 6 patients, 4 of whom received ≥73.0 Gy (E); local control was observed in 3 of these 4 patients for 2.9, 4.9, and 7.6 years. Conclusion: These data indicate a high local control rate for surgical and radiation treatment of primary (12 of 14) as distinct from recurrent (1 of 7) sacral chordomas. Three of 4 chordomas treated by ≥73.0 Gy (E) of radiation alone had local control; 1 is at 91 months. This indicates that high-dose proton/photon therapy offers an effective treatment option

Serum heme oxygenase-1 levels in patients with primary dysmenorrhea.

Science.gov (United States)

Aksoy, Ayse Nur; Laloglu, Esra; Ozkaya, Alev Lazoglu; Yilmaz, Emsal Pınar Topdagi

2017-04-01

Primary dysmenorrhea effects the life-quality of women negatively. The aim of this study was to evaluate heme oxygenase-1 (HO1) activity together with malondialdehyde (MDA) and nitric oxide (NO) levels in patients with primary dysmenorrhea. A total of 28 nulliparous women with the diagnosis of primary dysmenorrhea and 26 healthy controls were included in this study. On the first day of menstruation, all patients underwent ultrasound examination to exclude pelvic pathology and the visual analogue scale was applied to patients. Patient's visual analogue scale (VAS) scores, age, body mass index (BMI), menstrual cycle length (day), length of bleeding (day) were recorded. In the same day, fasting blood samples were taken from each patient for biochemical analysis. Serum MDA, NO and HO1 levels were found to be higher in women with primary dysmenorrhea compared to healthy controls (p = 0.012, p = 0.009, p dysmenorrhea. Antioxidant support might be helpful to reduce pain severity in primary dysmenorrhea.

Radiation Dose Contribution To The Worker Health Level At Serpong Area

International Nuclear Information System (INIS)

Yuwono, Indro

2000-01-01

Analysis of internal and external radiation doses received for radiation and non-radiation workers of P2TBDU have been done. In the period of 1997/1998 and 1998/1999 there were no significant increasing level of radiation doses received that was 0.55 mSv and highest received radiation dose was 2.66% from dose limit value. Increasing of healthy difference on the same period was 5.76%. Increasing of healthy difference no cause by increasing of radiation dose received but maybe the food consumption design

Epidemiological studies on the effects of low-level ionizing radiation on cancer risk

International Nuclear Information System (INIS)

Akiba, Suminori

2010-01-01

The health effects of low-level ionizing radiation are yet unclear. As pointed out by Upton in his review (Upton, 1989), low-level ionizing radiation seems to have different biological effects from what high-level radiation has. If so, the hazard identification of ionizing radiation should he conducted separately for low- and high-level ionizing radiation; the hazard identification of low-level radiation is yet to be completed. What makes hazard identification of ionizing radiation difficult, particularly in the case of carcinogenic effect, is the difficulty in distinguishing radiation-induced cancer from other cancers with respect to clinicopathological features and molecular biological characteristics. Actually, it is suspected that radiation-induced carcinogenesis involves mechanisms not specific for radiation, such as oxidative stress. Excess risk per dose in medium-high dose ranges can be extrapolated to a low-dose range if dose-response can be described by the linear-non-threshold model. The cancer risk data of atomic-bomb survivors describes leukemia risk with a linear-quadratic (LQ) model and solid-cancer risk with linear non-threshold (LNT) model. The LQ model for leukemia and the LNT model for solid cancer correspond to the two-hit model and the one-hit model, respectively. Although the one-hit model is an unlikely dose-response for carcinogenesis, there is no convincing epidemiological evidence supporting the LQ model or non-threshold model for solid cancer. It should be pointed out, however, even if the true dose response is non-linear various noises involved in epidemiological data may mask the truth. In this paper, the potential contribution of epidemiological studies on nuclear workers and residents in high background radiation areas will be discussed. (author)

Effect of low doses of ionizing radiation on circulating microparticles levels

International Nuclear Information System (INIS)

Ekhtiar, A.; Al-Massarani, Gh.; Najjar, F.; Aljapawe, A.

2015-01-01

Ionizing radiation is known to cause disruption of cytoskeleton. Cytoskeleton disorganization results in circulating microvesicles (MVs). The aim of this study was to investigate the relationship between the exposure to low-radiation and MVs levels in the peripheral blood of individuals working in radiation technology field.(author)

[Staffing levels in medical radiation physics in radiation therapy in Germany. Summary of a questionnaire].

Science.gov (United States)

Leetz, Hans-Karl; Eipper, Hermann Hans; Gfirtner, Hans; Schneider, Peter; Welker, Klaus

2003-10-01

To get a general idea of the actual staffing level situation in medical radiation physics in 1999 a survey was carried out by the task-group "Personalbedarf" of Deutsche Gesellschaft für Medizinische Physik (DGMP) among all DGMP-members who are active in this field. Main components for equipment and activities are defined in Report 8 and 10 of DGMP for staffing requirements in medical radiation physics. 322 forms were sent out, 173 of them have been evaluated. From the answers regarding equipment and activities numbers for staff are calculated by the methods given in Report 8 and 10 for this spot check target and compared with effective staffing levels. The data of the spot check are then extrapolated on total Germany. The result is a calculated deficit of 865 medical physicists for the whole physics staff, 166 of them in radiation therapy. From the age distribution of DGMP-members and the calculated deficit resulted a training capacity of about 100 medical physicists at all per year (19 in radiation therapy) if the deficit shall be cut back in 10 years.

Determination of radiation levels by neutrons in an accelerator for radiotherapy

International Nuclear Information System (INIS)

Paredes G, L.; Salazar B, M.A.; Genis S, R.

1998-01-01

It was determined the radiation levels by neutrons due to photonuclear reactions (γ, n) which occur in the target, levelling filter, collimators and the small pillow blinding of a medical accelerator Varian Clinac 2100C of 18 MeV, using thermoluminescent dosemeters UD-802AS and US-809AS. The experimental values were presented for the patient level, inside and outside of the radiation field, as well as for the small pillow. (Author)

Resistance of Feather-Associated Bacteria to Intermediate Levels of Ionizing Radiation near Chernobyl.

Science.gov (United States)

Ruiz-González, Mario Xavier; Czirják, Gábor Árpád; Genevaux, Pierre; Møller, Anders Pape; Mousseau, Timothy Alexander; Heeb, Philipp

2016-03-15

Ionizing radiation has been shown to produce negative effects on organisms, although little is known about its ecological and evolutionary effects. As a study model, we isolated bacteria associated with feathers from barn swallows Hirundo rustica from three study areas around Chernobyl differing in background ionizing radiation levels and one control study site in Denmark. Each bacterial community was exposed to four different γ radiation doses ranging from 0.46 to 3.96 kGy to test whether chronic exposure to radiation had selected for resistant bacterial strains. Experimental radiation duration had an increasingly overall negative effect on the survival of all bacterial communities. After exposure to γ radiation, bacteria isolated from the site with intermediate background radiation levels survived better and produced more colonies than the bacterial communities from other study sites with higher or lower background radiation levels. Long-term effects of radiation in natural populations might be an important selective pressure on traits of bacteria that facilitate survival in certain environments. Our findings indicate the importance of further studies to understand the proximate mechanisms acting to buffer the negative effects of ionizing radiation in natural populations.

Low level radiation: how low can you get?

International Nuclear Information System (INIS)

Townsley, M.

1990-01-01

Information stored on the world's largest data bank concerning the health of nuclear industry workers is to be handed over to researchers at Birmingham University by the US Department of Energy. The data bank contains detailed information on 300,000 nuclear employees, going back to the 1940s. Such a large sample size will allow the results of a previous study conducted on workers in the US nuclear industry to be verified. That study was concluded in 1978 and showed that the risk estimates set by the International Commission on Radiological Protection (ICRP) were between 10 and 30 times too low. The current ICRP estimate allows workers up to 50mSv of exposure to low level radiation per year. Risk estimates have been derived from data relating to the atomic bombings of Hiroshima and Nagasaki. However in those cases the radiation doses were relatively high but over a short period. In the nuclear industry the doses are lower but are long term and this may account for the apparent anomalies such as the incidence of leukaemia amongst children whose fathers have worked in the nuclear industry compared with that for the children whose fathers received radiation doses from the atomic bombings. It is expected the study will show that low-level radiation is more damaging than has previously been thought. (author)

Quality control methodology and implementation of X-radiation standards beams, mammography level, following the standard IEC 61267

International Nuclear Information System (INIS)

Correa, Eduardo de Lima

2010-01-01

In this work it was developed and applied a quality control program of the X radiation system (160 kV, constant potential, target of tungsten) of the Calibration Laboratory of IPEN(LCI) in the energy range relative to mammography beams (from 25 kV to 35 kV). The X radiation standards beams, level mammography, using molybdenum and aluminum as additional filtration, were established after the application of this quality control program following national and international recommendations. The reference ionization chamber has traceability to PTB and was regularly submitted to quality control tests for evaluation and analysis of its performance. The radiation qualities emerging from the X-radiation assembly (RQR-M), based on a phantom made up of an aluminum added filter (RQA-M), narrow beam condition (RQN-M) and broad beam condition (RQB-M), following the recommendations of the international standard IEC 61267 (2005) and the IAEA code of practice, TRS 457 (2007) were established. For the implantation of RQN-M and RQB-M radiation qualities, two mammography phantoms were developed. The half-value layers found are those presented by the German primary laboratory PTB, and varied from 0.35 to 1.21 mm Al. The air kerma rates were obtained for all the 15 implanted qualities. (author)

Safety Analysis Report for Primary Capsule of Ir-192 Radiation Source

International Nuclear Information System (INIS)

Lee, J. C.; Bang, K. S.; Choi, W. S.; Seo, K. S.; Son, K. J.; Park, W. J.

2008-12-01

All of the source capsules to transport a special form radioactive material should be designed and fabricated in accordance with the design criteria prescribed in IAEA standards and domestic regulations. The objective of this project is to prove the safety of a primary capsule for Ir-192 radiation source which produced in the HANARO. The safety tests of primary capsules were carried out for the impact, percussion and heat conditions. And leakage tests were carried out before and after the each tests. The capsule showed slight scratches and their deformations were not found after each tests. It also met the allowable limits of leakage rate after each test. Therefore, it has been verified that the capsule was designed and fabricated to meet all requirements for the special form radioactive materials

Radiation dosimetry and radiation biophysics

International Nuclear Information System (INIS)

Anon.

1981-01-01

Radiation dosimetry and radiation biophysics are two closely integrated programs whose joint purpose is to explore the connections between the primary physical events produced by radiation and their biological consequences in cellular systems. The radiation dosimetry program includes the theoretical description of primary events and their connection with the observable biological effects. This program also is concerned with the design and measurement of physical parameters used in theory or to support biological experiments. The radiation biophysics program tests and uses the theoretical developments for experimental design, and provides information for further theoretical development through experiments on cellular systems

Radiation dosimetry and radiation biophysics

International Nuclear Information System (INIS)

Anon.

1979-01-01

Radiation dosimetry and radiation biophysics are two closely integrated programs whose joint purpose is to explore the connections between the primary physical events produced by radiation and their biological consequences in cellular systems. The radiation dosimetry program includes the theoretical description of primary events and their connection with the observable biological effects. This program also is concerned with design and measurement of those physical parameters used in the theory or to support biological experiments. The radiation biophysics program tests and makes use of the theoretical developments for experimental design. Also, this program provides information for further theoretical development through experiments on cellular systems

High LET radiation shows no major cellular and functional effects on primary cardiomyocytes in vitro

Science.gov (United States)

Heselich, Anja; Frieß, Johannes L.; Ritter, Sylvia; Benz, Naja P.; Layer, Paul G.; Thielemann, Christiane

2018-02-01

It is well known that ionizing radiation causes adverse effects on various mammalian tissues. However, there is little information on the biological effects of heavy ion radiation on the heart. In order to fill this gap, we systematically examined DNA-damage induction and repair, as well as proliferation and apoptosis in avian cardiomyocyte cultures irradiated with heavy ions such as titanium and iron, relevant for manned space-flight, and carbon ions, as used for radiotherapy. Further, and to our knowledge for the first time, we analyzed the effect of heavy ion radiation on the electrophysiology of primary cardiomyocytes derived from chicken embryos using the non-invasive microelectrode array (MEA) technology. As electrophysiological endpoints beat rate and field action potential duration were analyzed. The cultures clearly exhibited the capacity to repair induced DNA damage almost completely within 24 h, even at doses of 7 Gy, and almost completely recovered from radiation-induced changes in proliferative behavior. Interestingly, no significant effects on apoptosis could be detected. Especially the functionality of primary cardiac cells exhibited a surprisingly high robustness against heavy ion radiation, even at doses of up to 7 Gy. In contrast to our previous study with X-rays the beat rate remained more or less unaffected after heavy ion radiation, independently of beam quality. The only change we could observe was an increase of the field action potential duration of up to 30% after titanium irradiation, diminishing within the following three days. This potentially pathological observation may be an indication that heavy ion irradiation at high doses could bear a long-term risk for cardiovascular disease induction.

Radiation Levels around the LHC

CERN Document Server

Mala, P; Calviani, M; Nordt, A

2013-01-01

This work discuss on the radiation levels measured around the LHC machine during the 2012 operational year. The doses and particle fluences are measured primarily by RadMon detectors – about 300 RadMons are installed around the accelerator – and by thermoluminescent detectors. In addition, BLMs, IG5/PMI ionisation chambers as well as FGCs can be used for corresponding cumulated dose evaluations. The probability of SEE depends directly on the high-energy hadron (HEH) fluence, so this is the main parameter that is calculated based on RadMons counts.

Environmental radiation levels around Nuclear Fuel Complex, Hyderabad during 1981-1988

International Nuclear Information System (INIS)

Mehta, Navnit; Lakshmanan, A.R.; Kathuria, S.P.; Nambi, K.S.V.

1989-01-01

This report presents environmental radiation monitoring results around Nuclear Ffuel Complex (NFC) at Hyderabad for the period, 1981-'88. During 1981-'83 only indoor radiations were monitored at 12 locations in the region of about 15 km. radius around NFC plant. However, during 1984-'88 both indoor and outdoor monitoring was done in a standardised manner at 8 locations. In this routine monitoring programme, environmental thermoluminescent dosimeters were used in quarterly integrating cycles. The average outdoor natural radiation level around NFC during 1984-'88 is found to be 227 ± 34 (σ) mR/y, which is the highest among the various sites in the country where DAE units are located. Such a high level of natural background radiation in and around Hyderabad is due to granitic terrains which normally have significant amounts of primordial radioactivity. The indoor to outdoor radiation ratio is found to be 1.35 ± 0.1 (σ). Application of this ratio on all the available indoor radiation monitoring results of 1981-'88 gives an estimate of 230 ± 26 mR/y as the average outdoor radiation level, and this is in very close agreement with the directly measured value mentioned earlier. The temporal variations seen in the quarterly results of each location have been tested for Normal and Log-Normal distributions and found to yield satisfactory correlations, although the plots reveal slight skewness; the latter however, could not be attributed to the NFC operations. (author). 7 refs., 4 tabs., 12 figs

Radiation protection in space

Energy Technology Data Exchange (ETDEWEB)

Blakely, E.A. [Lawrence Berkeley Lab., CA (United States); Fry, R.J.M. [Oak Ridge National Lab., TN (United States)

1995-02-01

The challenge for planning radiation protection in space is to estimate the risk of events of low probability after low levels of irradiation. This work has revealed many gaps in the present state of knowledge that require further study. Despite investigations of several irradiated populations, the atomic-bomb survivors remain the primary basis for estimating the risk of ionizing radiation. Compared to previous estimates, two new independent evaluations of available information indicate a significantly greater risk of stochastic effects of radiation (cancer and genetic effects) by about a factor of three for radiation workers. This paper presents a brief historical perspective of the international effort to assure radiation protection in space.

Radiation protection in space

International Nuclear Information System (INIS)

Blakely, E.A.; Fry, R.J.M.

1995-01-01

The challenge for planning radiation protection in space is to estimate the risk of events of low probability after low levels of irradiation. This work has revealed many gaps in the present state of knowledge that require further study. Despite investigations of several irradiated populations, the atomic-bomb survivors remain the primary basis for estimating the risk of ionizing radiation. Compared to previous estimates, two new independent evaluations of available information indicate a significantly greater risk of stochastic effects of radiation (cancer and genetic effects) by about a factor of three for radiation workers. This paper presents a brief historical perspective of the international effort to assure radiation protection in space

Radiation and man - evaluation of biological and environmental low level radiation effects

International Nuclear Information System (INIS)

Riklis, E.

1977-01-01

The harmful effects of acute radiation cannot be resolved by statistical means and require clearer knowledge of mechanisms of action and much wider collection of human experience before any definite sound stand can be taken. Much information has accumulated from animal experiments, and still the interpretations are not always clearcut, but for human experience it is only the occasional accident which can give a direct answer. Some of the phenomena attributed to low dose radiation are summarized. There are regions of radiation exposure about which we have only limited positive knowledge, an all low-dose risk estimates have been based on effects observed at relatively high doses. Much information has been gathered which does not support the severity of former basic principles, especially our knowledge of mechanisms of repair existing in most cells as natural defence against the damages caused by radiation as well as by many chemicals which act as mutagenic and carcinogenic agents. Understanding these mechanism, their scope of action and their availability to a damaged cell and organism will lead towards modification of the acceptable permissible exposures, in some cases towards severity, but in most cases towards leniency and higher values. For the evaluation of the effects of low level low dose-rate radiations, whether external, or from internal deposition of isotopes, only late somatic and genetic effects should be considered. (B.G.)

Dual-Energy Micro-Computed Tomography Imaging of Radiation-Induced Vascular Changes in Primary Mouse Sarcomas

International Nuclear Information System (INIS)

Moding, Everett J.; Clark, Darin P.; Qi, Yi; Li, Yifan; Ma, Yan; Ghaghada, Ketan; Johnson, G. Allan; Kirsch, David G.; Badea, Cristian T.

2013-01-01

Purpose: To evaluate the effects of radiation therapy on primary tumor vasculature using dual-energy (DE) micro-computed tomography (micro-CT). Methods and Materials: Primary sarcomas were generated with mutant Kras and p53. Unirradiated tumors were compared with tumors irradiated with 20 Gy. A liposomal-iodinated contrast agent was administered 1 day after treatment, and mice were imaged immediately after injection (day 1) and 3 days later (day 4) with DE micro-CT. CT-derived tumor sizes were used to assess tumor growth. After DE decomposition, iodine maps were used to assess tumor fractional blood volume (FBV) at day 1 and tumor vascular permeability at day 4. For comparison, tumor vascularity and vascular permeability were also evaluated histologically by use of CD31 immunofluorescence and fluorescently-labeled dextrans. Results: Radiation treatment significantly decreased tumor growth from day 1 to day 4 (P 2 =0.53) and dextran accumulation (R 2 =0.63) on day 4, respectively. Despite no change in MVD measured by histology, tumor FBV significantly increased after irradiation as measured by DE micro-CT (0.070 vs 0.091, P<.05). Both dextran and liposomal-iodine accumulation in tumors increased significantly after irradiation, with dextran fractional area increasing 5.2-fold and liposomal-iodine concentration increasing 4.0-fold. Conclusions: DE micro-CT is an effective tool for noninvasive assessment of vascular changes in primary tumors. Tumor blood volume and vascular permeability increased after a single therapeutic dose of radiation treatment

Experience of water chemistry and radiation levels in Swedish BWRs

International Nuclear Information System (INIS)

Ivars, R.; Elkert, J.

1981-01-01

From the BWR operational experience in Sweden it has been found that the occupational radiation exposures have been comparatively low in an international comparison. One main reason for the favourable conditions is the good water chemistry performance. This paper deals at first with the design considerations of water chemistry and materials selection. Next, the experience of water chemistry and radiation levels are provided. Finally, some methods to further reduce the radiation sources are discussed. (author)

Selectivity of primary events in the radiation chemistry of organic solids and polymers as revealed by model studies of ionized molecules

International Nuclear Information System (INIS)

Feldman, V.

2006-01-01

Selectivity of the primary chemical events induced by ionizing radiation in molecular systems is the key issue of basic radiation chemistry, which is crucially important for controlling the radiation sensitivity of various-type organic and polymeric materials and designing new effective approaches to the radiation modification. In the past decade we have demonstrated that many features of selective localization of the radiation-induced effects in molecular solids can be understood on the basis of model studies of the primary ionized molecules in rigid low-temperature matrices. This talk will outline the key results of these studies and possible implications for radiation chemistry of vatious systems. In particular, the following aspects will be considered: (1) Spectroscopic characteristics of ustable ionized molecules in low-temperature matrices and their correlations with the site-selective reactivity. (2) Experimental modeling of the effect of excess energy on the properties of primary ionized molecules in condensed phases. (3) Intramolecular long-range effects with particular impact on the properties of ionized bifunctional molecules of X-(CH 2 ) n -X and X-(CH 2 ) n -Y types. (4) Modeling of intermolecular long-range positive hole transfer between molecular traps with close ionization energy and manifestations of 'fine tuning' effects resulting from conformation variations and intermolecular interactions. Several illustrative examples of correlation between the properties of primary ionized molecules and selectivity of the radiation-chemical transformations in organic solids and macromolecules will be presented. Finally, the problem of prediction of the radiation-chemical behaviour of complex organic systems on the basis of limited spectroscopic information and quantum-chemical data obtained for model systems will be addressed. This work was supported by the Russian Foundation for Basic Research (Project No. 06-03-33104) and the Russian Academy of Sciences

Measurement of Background Gamma Radiation Levels at Two ...

African Journals Online (AJOL)

MICHAEL

ABSTRACT: An in-situ measurement of the background radiation level was carried out at the vicinity of three ... Soil contains small quantities of radioactive elements along with their progeny. .... assessment for soil samples from Kestanbol.

Low level radiation testing of micro-electronic components. Pt. 1

International Nuclear Information System (INIS)

Farren, J.; Stephen, J.H.; Mapper, D.; Sanderson, T.K.; Hardman, M.

1984-05-01

A review of the existing literature has been carried out, dealing with the current technology relating to low level radiation testing of microelectronic devices, as used in space satellite systems. After consideration of the space radiation environment, the general effects of cosmic radiation on MOSFET structures and other MOS devices have been assessed. The important aspect of annealing phenomena in relation to gamma-ray induced damage has also been reviewed in detail. The experimental and theoretical aspects of radiation testing have been assessed, with particular reference to the Harwell LORAD low level irradiation test facility. In addition, a review of modern dosimetry methods has been carried out, with specific regard to the problems of accurately measuring low radiation fields (1 to 10 R/hour) over periods of many months. Finally, a detailed account of the proposed experimental programme to be carried out in the LORAD facility is presented, and aspects of the experimental set-up discussed. The particular types of test circuits to be studied are dealt with, and full consideration is given to the various CMOS memory devices of special interest in the ESA space satellite programme. (author)

Doses of low level ionizing radiation; a misunderstood risk, however unavoidable

International Nuclear Information System (INIS)

Nicolli, D.

1988-01-01

The treatment given by international organizations and associations to the problems of radiation exposures, and the recommendations and norms for calculating risks of low level radiation are analysed. It is shown that there are not zero risks for nuclear energy, and emphasis is given to the risks of natural radiation from environment. (M.C.K.) [pt

Radiation and Homeostasis

International Nuclear Information System (INIS)

Sugahara, T.; Nikaido, O.; Niwa, O.

2002-01-01

These proceedings aim to promote the understanding of the health hazard of radiation at low dose range and to construct a more solid basis for radiation safety policy. Radiation hazard has been the central issue of investigation in the field of radiation research. The two major approaches are mechanistic analysis by laboratory investigation and phenomenological analysis of radiation-exposed population as represented by epidemiology. In an increasingly safety-conscious society, the extremely low level risk associated with low dose of radiation has become an important issue. In this area, the phenomenological approach has a limit. DNA damage is the primary and direct cause of the risk. Tremendous progress has been made recently in the basic understanding of radiation effects on cells and tissues and the importance of damage response rather than damage itself. This challenges the classical linear non-threshold hypothesis

Site-level evaluation of satellite-based global terrestrial gross primary production and net primary production monitoring.

Science.gov (United States)

David P. Turner; William D. Ritts; Warren B. Cohen; Thomas K. Maeirsperger; Stith T. Gower; Al A. Kirschbaum; Steve W. Runnings; Maosheng Zhaos; Steven C. Wofsy; Allison L. Dunn; Beverly E. Law; John L. Campbell; Walter C. Oechel; Hyo Jung Kwon; Tilden P. Meyers; Eric E. Small; Shirley A. Kurc; John A. Gamon

2005-01-01

Operational monitoring of global terrestrial gross primary production (GPP) and net primary production (NPP) is now underway using imagery from the satellite-borne Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. Evaluation of MODIS GPP and NPP products will require site-level studies across a range of biomes, with close attention to numerous scaling...

Ionizing radiation increases primary cilia incidence and induces multiciliation in C2C12 myoblasts

Czech Academy of Sciences Publication Activity Database

Filipová, A.; Diaz-Garcia, D.; Bezrouk, A.; Čížková, D.; Havelek, R.; Vávrová, J.; Dayanithi, Govindan; Řezáčová, M.

2015-01-01

Roč. 39, č. 8 (2015), s. 943-953 ISSN 1065-6995 Institutional support: RVO:68378041 Keywords : cell line * ionizing radiation * multiple cilia * myoblast * primary cilium * serum starvation stress Subject RIV: FP - Other Medical Disciplines Impact factor: 1.663, year: 2015

Calibration methodology for instruments utilized in X radiation beams, diagnostic level

International Nuclear Information System (INIS)

Penha, M. da; Potiens, A.; Caldas, L.V.E.

2004-01-01

Methodologies for the calibration of diagnostic radiology instruments were established at the Calibration Laboratory of IPEN. The methods may be used in the calibration procedures of survey meters used in radiation protection measurements (scattered radiation), instruments used in direct beams (attenuated and non attenuated beams) and quality control instruments. The established qualities are recommended by the international standards IEC 1267 and ISO 4037-3. Two ionization chambers were used as reference systems, one with a volume of 30 cm 3 for radiation protection measurements, and the other with a volume of 1 cm 3 for direct beam measurements. Both are traceable to the German Primary Laboratory of Physikalisch-Technische Bundesanstalt (PTB). In the case of calibration of quality control instruments, a non-invasive method using the measurement of the spectrum endpoint was established with a portable gamma and X-ray Intertechnique spectrometer system. The methods were applied to survey meters (radiation protection measurements), ionization chambers (direct beam measurements) and k Vp meters (invasive and non-invasive instruments). (Author)

Calibration methodology for instruments utilized in X radiation beams, diagnostic level

Energy Technology Data Exchange (ETDEWEB)

Penha, M. da; Potiens, A.; Caldas, L.V.E. [Instituto de Pesquisas Energeticas e Nucleares, Comissao Nacional de Energia Nuclear, Sao Paulo (Brazil)]. E-mail: mppalbu@ipen.br

2004-07-01

Methodologies for the calibration of diagnostic radiology instruments were established at the Calibration Laboratory of IPEN. The methods may be used in the calibration procedures of survey meters used in radiation protection measurements (scattered radiation), instruments used in direct beams (attenuated and non attenuated beams) and quality control instruments. The established qualities are recommended by the international standards IEC 1267 and ISO 4037-3. Two ionization chambers were used as reference systems, one with a volume of 30 cm{sup 3} for radiation protection measurements, and the other with a volume of 1 cm{sup 3} for direct beam measurements. Both are traceable to the German Primary Laboratory of Physikalisch-Technische Bundesanstalt (PTB). In the case of calibration of quality control instruments, a non-invasive method using the measurement of the spectrum endpoint was established with a portable gamma and X-ray Intertechnique spectrometer system. The methods were applied to survey meters (radiation protection measurements), ionization chambers (direct beam measurements) and k Vp meters (invasive and non-invasive instruments). (Author)

Estimation of natural radiation background level and population dose in China

International Nuclear Information System (INIS)

Pan Ziqiang

1992-01-01

The authors describe in general the natural radiation background level in China, and based on available data present an estimated annual effective dose equivalent of the population to natural radiation that is some 2.3 mSv, of which about 0.54 mSv is from original γ radiation and about 0.8 mSv from radon and its short-lived daughters

Effect of sublethal levels of ionizing radiation on a predator-prey interaction

International Nuclear Information System (INIS)

Chee, P.C.

1976-01-01

The predator-prey interaction studied was that between the largemouth bass (Micropterus salmoides) and the fathead minnow (Pimephales promelas) in an artificial test environment. Experiments were first conducted to determine the 50% lethal dose at 30 days of the minnow. Three different dose rates were used to test the effect of dose rate on the 50% lethal dose value. After the 50% lethal dose was determined the predator-prey interaction experiment was conducted using 30% of the 50% lethal dose as the highest radiation dose, this dose being considered the upper limit to sublethal radiation levels. A 4 x 4 Latin square design was chosen for the experiment, with four treatment levels (control plus three radiation levels) and four replicates. In each test 10 prey minnow were offered to one predator bass and the number of prey left after 14 days was the parameter of interest. A predator-prey interaction experiment using a single high level of radiation and two types of controls as conducted to ascertain the ability of the test environment to detect changes in the predator-prey interaction. The two types of controls were irradiated prey not exposed to predation and non-irradiated prey exposed to predation. An experiment was also conducted to test the correlation between the physical activity patterns of minnow and different doses of radiation. At a dose rate of 37.8 rad/min the 50% lethal dose at 30 days for minnow was found to be 2650 rad. It was found that dose rate had a strong influence on the 50% lethal dose. In the predator-prey interaction test it was found that the 14-day survival rate of prey was unaffected by sublethal levels of ionizing radiation. No significant correlation was detected between the physical activity patterns of minnow and radiation dose

Serum testosterone levels after external beam radiation for clinically localized prostate cancer

International Nuclear Information System (INIS)

Zagars, Gunar K.; Pollack, Alan

1997-01-01

Purpose: To determine whether serum total testosterone levels change after external beam radiation therapy for localized prostate cancer. Methods and Materials: Eighty-five men with clinically localized prostate cancer (T1-T3, N0/NX, M0) who underwent external beam radiation therapy without androgen ablation had pretreatment and 3-month posttreatment total serum testosterone levels determined by radioimmunoassay. Scattered doses to the testicles were measured with thermoluminescent dosimetry in 10 men. Results: Pretreatment serum testosterone levels ranged from 185 to 783 ng/dl, with a mean of 400 ng/dl and a median of 390 ng/dl. The coefficient of variation was 30%. Postradiation 3-month testosterone levels ranged from 163 ng/dl to 796 ng/dl, with mean and median values of 356 ng/dl and 327 ng/ml, respectively. The coefficient of variation was 34%. The 3-month value was significantly lower than the pretreatment value (Wilcoxon paired p = 0.0001). The mean absolute fall was 94 ng/dl and the mean percentage fall was 9%. Although the fall in testosterone level was statistically significant, the difference was very small quantitatively. In contrast, serum prostate-specific antigen levels fell dramatically by 3 months after radiation. Testicular scattered doses ranged from 1.84 to 2.42 Gy, with a mean of 2.07 Gy for a prostatic tumor dose of 68 Gy. Conclusions: Although significant, the fall in serum testosterone level after radiation for localized prostate cancer was small and likely of no pathophysiologic consequence. It is unlikely that scattered testicular radiation plays any significant role in the genesis of this change in testosterone level, which most likely occurs as a nonspecific stress response

Environmental radiation level, radiation anxiety, and psychological distress of non-evacuee residents in Fukushima five years after the Great East Japan Earthquake: Multilevel analyses

Directory of Open Access Journals (Sweden)

Maiko Fukasawa

2017-12-01

Full Text Available The present study aimed to clarify the associations among radiation exposure or psychological exposure to the Fukushima nuclear power plant accident (i.e., fear/anxiety immediately after the accident, current radiation anxiety, and psychological distress among non-evacuee community residents in Fukushima five years after the Great East Japan Earthquake, which occurred in March 2011. A questionnaire survey was administered to a random sample of non-evacuee community residents from 49 municipalities of Fukushima prefecture from February to April 2016, and data from 1684 respondents (34.4% were analyzed. Environmental radiation levels at the time of the accident were ascertained from survey meter data, while environmental radiation levels at the time of the survey were ascertained from monitoring post data. In the questionnaire, immediate fear/anxiety after the accident, current radiation anxiety, and psychological distress were measured using a single-item question, a 7-item scale, and K6, respectively. Multilevel linear or logistic regression models were applied to analyze the determinants of radiation anxiety and psychological distress. The findings showed that environmental radiation levels at the time of the survey were more strongly associated with radiation anxiety than radiation levels immediately after the accident. Disaster-related experiences, such as direct damage, disaster-related family stress, and fear/anxiety after the accident, and demographic characteristics (e.g., younger age, being married, low socioeconomic status were significantly associated with radiation anxiety. Environmental radiation levels at the time of the accident or survey were not significantly associated with psychological distress. Radiation anxiety largely mediated the association between fear/anxiety after the accident and psychological distress. In addition to environmental radiation levels, respondents’ radiation anxiety was affected by multiple factors

Expression of chalcone synthase genes in coleoptiles and primary leaves of Secale cereale L. after induction by UV radiation: evidence for a UV-protective role of the coleoptile

International Nuclear Information System (INIS)

Haussühl, K.; Rohde, W.; Weissenböck, G.

1996-01-01

Four chalcone synthase (CHS; EC 2.3.1.74) clones from rye were isolated and characterized. Two of these clones were used for analysis of CHS gene activities in response to ultraviolet and visible radiation in the coleoptile and the primary leaf of the rye seedling. The time-dependence of CHS gene activation and the spatial distribution of CHS were studied by investigation of enzyme activities and CHS mRNA levels, including in situ RNA hybridization. In the primary leaf strong induction of CHS gene activity was localized in the epidermal layers and only marginally found in the mesophyll. The coleoptile showed an even higher response to UV irradiation, but CHS gene activity was evenly distributed throughout the tissues. It is suggested that, in addition to its function as a mechanical protection for the primary leaf during seed germination and seedling emergence through the soil, the coleoptile may also protect the emerging seedling from harmful radiation

Investigation on the acceptance level of radiation exposure. Comparison of Chinese and Japanese

International Nuclear Information System (INIS)

Wu, Jin; Katoh, Kazuaki

1999-01-01

Safety standards must be determined with the contract between a society and the person concerned, i.e. the agreement in a social community. Individual understandings on the (ionizing) radiation should be proper and uniform as far as possible, just in the case. The individual acceptable radiation dose level of a constituent of a community is one of the key roles for radiation managements and also coping with radiofobia (persons who have hatred and/or allergic syndromes for the radiation). The authors have obtained information by means of questionnaires on the acceptable dose levels of the radiation for 2 groups in a community, the one is a medical science group and the other is a science-technology group in both countries, China and Japan. The annual natural radiation dose etc. are described with inquiries to preclude meaningless responses. The levels of the acceptable radiation dose are different in individuals and show wide distributions. The gap between the two acceptable dose levels for a person is narrow, i.e. the one is the minimum radiation dose that a person rejects with dread and the other is the maximum dose that a person does not have any anxiety. The Japanese science-technology group shows the significant higher dose than that of the Chinese science-technology group. The Chinese medical science group shows the significant higher dose than that of the Chinese science-technology group. The Japanese medical science group does not show the statistically significant difference from the Japanese science-technology group. A perception for the radiation exposure and safety is unexpectedly scattered from person to person even though among the high-level intellectual groups mentioned above. There is no difference on this scattering between the Japan and China. (Y. Tanaka)

Measurement and evaluation of the external radiation level at reactor Kartini

International Nuclear Information System (INIS)

Atok Suhartanto; Suparno

2013-01-01

Measurement and evaluation of external radiation level at reactor Kartini in 2012 has been done. The purpose of this activity is to know the external radiation level as a result of the radioactive or radiation source usage, toward the operational of limit condition. The measurement is using survey meter Inspector 11086, factor of calibration 0.991 mR/h, at 9 locations is: Control room area, Thermal column facilities, Demineralizer, Beamport radiography facilities, bulk shielding Deck, Subcritical facilities, Reactor hall, Deck reactor and on the surface of reactor water tank . The highest room average measurement result in 9 working areas for 12 months continuously are at the reactor tank location is between 13.05±1.09 (xlO -2 mSv/hour) to 16.80±1.40 (x10 -2 mSv/hour), and the lowest measurement result in 1 location (control room) is 0.02±0.005 (x10 -2 mSv/hour) to 0.035±0.009 (x10 -2 mSv/hour). The Kartini reactor is involved in the control area which has potentially contaminated and has radiation exposure at the level of 6 mSv/year. Radiation Protection Officer that work in interval will received radiation exposure dosage of 8.4 mSv/year. This dosage is still below the Below Dosage Value which is recommended by, BAPETEN decree No, 4, 2013 about Protection and Radiation Safety in Nuclear Energy Application at 20 mSv/year. The result of the evaluation above shows that the external radiation which occurred in each area is still below the operational of limit condition that is written on the Kartini reactor safety analysis report, on document number: C7/05/B2/LAK/2010, revision 7. So that the workplace is safe for work monitored. (author)

Ambient radiation levels in positron emission tomography/computed tomography (PET/CT) imaging center

Energy Technology Data Exchange (ETDEWEB)

Santana, Priscila do Carmo; Oliveira, Paulo Marcio Campos de; Mamede, Marcelo; Silveira, Mariana de Castro; Aguiar, Polyanna; Real, Raphaela Vila, E-mail: pridili@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Silva, Teogenes Augusto da [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2015-01-15

Objective: to evaluate the level of ambient radiation in a PET/CT center. Materials and methods: previously selected and calibrated TLD-100H thermoluminescent dosimeters were utilized to measure room radiation levels. During 32 days, the detectors were placed in several strategically selected points inside the PET/CT center and in adjacent buildings. After the exposure period the dosimeters were collected and processed to determine the radiation level. Results: in none of the points selected for measurements the values exceeded the radiation dose threshold for controlled area (5 mSv/ year) or free area (0.5 mSv/year) as recommended by the Brazilian regulations. Conclusion: in the present study the authors demonstrated that the whole shielding system is appropriate and, consequently, the workers are exposed to doses below the threshold established by Brazilian standards, provided the radiation protection standards are followed. (author)

Estimation of the Contribution of Primary and Secondary Radiation to a Pinhole Volume from a Water Phantom

International Nuclear Information System (INIS)

Gamage, Kelum-A.-A.; Joyce, Malcolm-J.; Taylor, Graeme-C.

2013-06-01

The imaging of mixed radiation fields with organic liquid scintillation detectors became feasible as a result of recent advances in digital pulse-shape discrimination methods. The use of a liquid scintillator has significant benefits over other techniques for imaging radiation environments as the acquired data can be analysed to provide separate information about the gamma and neutron emissions from a source (or sources) in a single scan in near real-time. This method has significant potential for the location of radioactive sources in radiation environments in the nuclear industry, nuclear decommissioning and homeland security applications. A further application of the mixed-field imaging system would be to detect, locate and study the secondary radiation produced during proton therapy. Proton therapy uses a particle accelerator to target a tumour within the body with a beam of protons. The presence of materials in the beam path as well as the patient, leads to the production of secondary particles such as neutrons and gamma rays. In this paper the contribution of scattered and secondary radiation from a water phantom to a pinhole volume, as a result of three neutron sources and two gamma sources, is separately estimated using the PTRAC particle tracking option available in MCNP. A spherical tally volume, 2 cm in diameter, was placed equidistantly from a radioactive source and 30*30*15 cm 3 water phantom. Monte Carlo simulations have been carried out to investigate the level of primary and secondary radiation contributing to the pinhole volume from interactions in the phantom. This can be used as a simple method to visualise the results expected from the mixed-field imaging system. The results have shown that the percentage of neutrons reflected from the phantom with energies above 1 MeV goes up with mean energy of the source. (authors)

Influence of hydrazine primary water chemistry on corrosion of fuel cladding and primary circuit components

International Nuclear Information System (INIS)

Iourmanov, V.; Pashevich, V.; Bogancs, J.; Tilky, P.; Schunk, J.; Pinter, T.

1999-01-01

Earlier at Paks 1-4 NPP standard ammonia chemistry was in use. The following station performance indicators were improved when hydrazine primary water chemistry was introduced: occupational radiation exposures of personnel; gamma-radiation dose rates near primary system components during refuelling and maintenance outages. The reduction of radiation exposures and radiation fields were achieved without significant expenses. Recent results of experimental studies allowed to explain the mechanism of hydrazine dosing influence on: corrosion rate of structure materials in primary coolant; behaviour of soluble and insoluble corrosion products including long-life corrosion-induced radionuclides in primary system during steady-state and transient operation modes; radiolytic generation of oxidising radiolytic products in core and its corrosion activity in primary system; radiation situation during refuelling and maintenance outages; foreign material degradation and removal (including corrosion active oxidant species) from primary system during abnormal events. Operational experience and experimental data have shown that hydrazine primary water chemistry allows to reduce corrosion wear and thereby makes it possible to extend the life-time of plant components in primary system. (author)

Radiation levels in eastern Europe

International Nuclear Information System (INIS)

Webb, G.A.M.; Simmonds, J.R.; Wilkins, B.T.

1986-01-01

Immediately after news of the accident at Chernobyl became available on 28 April, the National Radiological Protection Board (NRPB) was asked by the UK Foreign and Commonwealth Office (FCO) for an appraisal of the radiation situation on the basis of which advice would be given to embassy staff, residents in affected countries and prospective travellers. The first Swedish measurements, external gamma dose rates and, later, concentrations of atmospheric and ground radioactivity, were used to estimate the quantity of radioactivity released by means of NRPB's accident consequence code (1), MARC. Our first predictions of 29 April indicated a substantial release of the order of 10 17 - 10 18 Bq, which was expected to lead to tens of early radiation-induced deaths in the area around the site. On the basis of NRPB's recommended Emergency Reference Levels (ERL's), it was thought that there would be a need for evacuation out to 20 to 30 km and for temporary food restrictions out to a few hundred kilometres from the site. FCO accordingly decided to evacuate students from Kiev and Minsk and to advise people not to travel to the western Soviet Union or to north-east Poland unless absolutely necessary

An overview of radiation protection at national level in Greece

International Nuclear Information System (INIS)

Dimitriou, P.A.

1997-01-01

The Greek radiation protection Regulations were revised extensively and harmonized with the relevant Euratom Directives in 1991, covering almost all applications of ionizing radiation. According to the low in force, Greek Atomic Energy Commission (GAEC) is the regulatory and competent authority on radiation protection matters. Among others is responsible: for evaluating the environmental radiation, for introducing emergency plans to responsible Ministries to cope with radiation accidents or increased radioactivity levels, for issuing safety regulation concerning the operation employing ionizing radiation, performing inceptions to all installations or laboratories where radioisotopes or radiation producing machines are employed including all medical applications and issuing the certificate of compliance with the radiation protection regulations. GAEC is the governmental licensing authority for import, export, possession, use, transport and disposal of radioactive materials including fissile materials, and is also responsible for providing training and education to scientists and technical personnel on radiation protection and operates a two years postgraduate course in Medical radiation Physics in collaboration with three Greek Universities, leading to an M Sc degree.The achievements, initiatives and perceptivities of GAEC in the fields of its responsibility are discussed. Statistical data concerning the application of ionising radiation in Greece during the last five years are also presented (author)

Low-level radiation: a high-level concern

International Nuclear Information System (INIS)

Holden, C.

1979-01-01

The role of DOE in radiation health effects research is discussed. The possibility of conflict of interest is presented. The Mancuso episode is cited as evidence. The roles of several agencies (EPA, NRC, and OSHA) in establishing safe limits of radiation exposure are discussed

Time course of cerebellar catalase levels after neonatal ionizing radiations

International Nuclear Information System (INIS)

Di Meglio, A.; Caceres, L.; Zieher, L.M.; Guelman, L.R.

2005-01-01

Full text: Reactive oxygen species are physiologically generated as a consequence of aerobic respiration, but this generation is increased in response to external stimuli, including ionizing radiation. The central nervous system (CNS) is vulnerable to oxidative stress due to its high oxygen consumption rate, its high level of polyunsaturated fatty acids and low levels of antioxidant defences. An important compound of this defence system is the antioxidant enzyme catalase, an heme protein that removes hydrogen peroxide from the cell by catalyzing its conversion to water. The aim of the present work was to study if catalase is susceptible to oxidative stress generated by ionizing radiation on the cerebellum. Neonatal rats were irradiated with 5 Gy of X rays and the levels of catalase were measured at 15, 30 and 60 days of age. Results show that there is a decrease in the activity of catalase in irradiated cerebellum at 15 (% respect the control, 65.6 ± 14.8), 30 (51.35± 5.8%), and 60 days (9.3 ± 0.34%). Catalase activity at 15 and 30 days has shown to be positively correlated with the radiation-induced decrease in tissue's weight, while at 60 days there is an extra decrease. It would be suggested that, at long term, radiation exposure might induce, in addition to cerebellar atrophy, the oxidation of the radiosensitive heme group of the enzyme, leading to its inactivation. In conclusion, the antioxidant enzyme catalase has shown to be especially sensitive to ionizing radiation. (author)

Changes in Plasma Prolactin and Growth Hormone Level and Visual Problem after radiation Therapy(RT) of Pituitary Adenoma

International Nuclear Information System (INIS)

Yoon, Sei Chul; Kwon, Hyung Chul; Oh, Yoon Kyeong; Bahk, Yong Whee; Son, Ho Young; Kang, Joon Ki; Song, Jin Un

1985-01-01

Twenty-four cases of pituitary adenoma, 13 males and 11 females with the age ranging from 11 to 65 years, received radiation therapy(RT) on the pituitary area with 6MV linear accelerator during past 25 months at the Division of Radiation Therapy, Kangnam St. Mary Hospital, Catholic Medical College. Of 24 case of RT, 20 were postoperative and 4 primary. To evaluate the effect of RT, we analyzed the alteration of the endocrinological tests, neurologic abnormalities, major clinical symptoms, endocrinological changes and improvement in visual problems after RT. The results were as follows ; 1. Major clinical symptoms were headache, visual defects, diabetes insipidus, hypogonadisms and general weakness in decreasing order of frequency. 2. All but the one with Nelson syndrome showed abnormal neuroradiologic changes in the sella turcica with an invasive tumor mass around supra and para-sellar area. 3. Endocrinological classifications of the patient were 11 prolactinoma, 4 growth hormonesecreting tumors, 3 ACTH-secreting tumors consisting of one Cushing disease and two Nelson syndrome, and 6 nonfunctioning tumors. 4. Eleven of 14 patients, visual problems were improved after treatment but remaining 3 were unchanged. 5. Seven of 11 prolactinomas returned to normal hormonal level after postoperative and primary RT and 3 patients are being treated with bromocriptine (BMCP) but on lost case. 6. Two of 4 growth hormone-secreting tumor returned to normal level after RT but the remaining 2 are being treated with BMCP, as well

A survey on evaluation function for contaminations and doses in the primary and the secondary radiation emergency hospitals

International Nuclear Information System (INIS)

Yamada, Yuji; Akashi, Makoto; Shiraishi, Kunio; Suzuki, Toshikazu; Ishigure, Nobuhito; Endo, Akira; Sanada, Tetsuya; Nakayama, Kazushige; Shizuma, Kiyoshi; Takada, Chie; Momose, Takumaro; Hoshi, Masaharu; Yamaguchi, Takenori

2009-01-01

The questionnaire on evaluation function for contaminations and doses was sent to the primary and the secondary radiation emergency hospitals in Japan by the network council for physical dosimetry in National Institute of Radiological Sciences (NIRS) designated as the tertiary hospital. The recovery percentage from the 88 hospitals was 70%. It turned out that six primary hospitals in 37 hospitals did not have even the basic instruments on radiation measurement such as GM counter and personal dosimeter. 64% of the secondary hospitals have the whole body counter, but its operation frequency including exercise was considerably low. It is thought that the main cause originates in a chronic manpower shortage and the budget shortfall seen by all the primary and the secondary hospitals. And also peculiar difficulty of correspondence to the radiation emergency medical treatment and the few experience might promote the problem. Thus the anxiety of the site staff had been appeared to the result of the questionnaire survey in shape like the opinion and the demand, etc. It will be necessary to advance the enhancement of training and to make the manual for the contaminations and the doses evaluation in the hospitals. (author)

Incidence of primary hypothyroidism in patients exposed to therapeutic external beam radiation, where radiation portals include a part or whole of the thyroid gland

Directory of Open Access Journals (Sweden)

B A Laway

2012-01-01

Full Text Available Introduction: Hypothyroidism is a known consequence of external-beam radiotherapy to the neck encompassing a part or whole of the thyroid gland. In this non-randomized prospective study, we have tried to evaluate the response of the thyroid gland to radiation by assessing thyroid function before irradiation and at regular intervals after irradiation. Aims and Objectives: The aim of this study were to assess in the cancer patients, who were exposed to the therapeutic external beam radiation, where radiation portals include a part or whole of the thyroid gland: the incidence of primary hypothyroidism, the time required to become hypothyroid, any relation between the total dose for the development of hypothyroidism, and whether there are any patient or treatment-related factors that are predictive for the development of hypothyroidism, including the use of concurrent chemotherapy. Materials and Methods: This non-randomized, prospective study was conducted for a period of 2 years in which thyroid function was assessed in 59 patients (cases of head and neck cancer, breast cancer, lymphoma patients and other malignancies, who had received radiotherapy to the neck region. 59 euthyroid healthy patients (controls were also taken, who had not received the neck irradiation. These patients/controls were assessed periodically for 2 years. Results: The incidence of hypothyroidism after external beam radiation therapy (EBRT to neck where radiation portals include part or whole of the thyroid gland was 16.94%, seven cases had subclinical hypothyroidism (11.86% and three cases had clinical hypothyroidism (5.08%. Mean time for development of hypothyroidism was 4.5 months. There was no effect of age, gender, primary tumor site, radiation dose and chemotherapy, whether neoadjuvant or concurrent with the development of hypothyroidism. Conclusion: In summary, we found that thyroid dysfunction is a prevalent, yet easily treatable source of morbidity in patients

Ambient radiation levels in positron emission tomography/computed tomography (PET/CT) imaging center

Science.gov (United States)

Santana, Priscila do Carmo; de Oliveira, Paulo Marcio Campos; Mamede, Marcelo; Silveira, Mariana de Castro; Aguiar, Polyanna; Real, Raphaela Vila; da Silva, Teógenes Augusto

2015-01-01

Objective To evaluate the level of ambient radiation in a PET/CT center. Materials and Methods Previously selected and calibrated TLD-100H thermoluminescent dosimeters were utilized to measure room radiation levels. During 32 days, the detectors were placed in several strategically selected points inside the PET/CT center and in adjacent buildings. After the exposure period the dosimeters were collected and processed to determine the radiation level. Results In none of the points selected for measurements the values exceeded the radiation dose threshold for controlled area (5 mSv/year) or free area (0.5 mSv/year) as recommended by the Brazilian regulations. Conclusion In the present study the authors demonstrated that the whole shielding system is appropriate and, consequently, the workers are exposed to doses below the threshold established by Brazilian standards, provided the radiation protection standards are followed. PMID:25798004

Environments with elevated radiation levels from natural radioactive substances

International Nuclear Information System (INIS)

Sohrabi, M.

2000-01-01

Some areas in the world have elevated levels of radioactive substances in the environment forming elevated radiation areas (ERAs) where public potential annual effective doses can exceed even the dose limit of radiation workers. Such radioactive substances are either terrestrial natural radioactivity added naturally in the soil or natural and/or man-made radioactivity from human activities added into the environment. If radioactivity is added naturally, elevated natural radiation areas (ENRAs) are formed. Based on the classification criteria introduced by the author, such regions are divided into static and dynamic areas. They are also classified in accordance with their level of potential effective dose to the public. Some main ENRAs are classified. Highlights are presented of the results of activity studies carried out in selected areas. The concepts discussed can also be applied to areas formed by human activities. The author suggests some guidelines for future studies, regulatory control and decision making, bearing in mind the need for harmonization of policies for regulatory control and remedial actions at sites to protect the public from environmental chronic exposures. (author)

BEIR-III report and the health effects of low-level radiation

International Nuclear Information System (INIS)

Fabrikant, J.I.

1980-01-01

The present BEIR-III Committee has not highlighted any controversy over the health effects of low-level radiation. In its evaluation of the experimental data and epidemiological surveys, the Committee has carefully reviewed and assessed the value of all the available scientific evidence for estimating numerical risk coefficients for the health hazards to human populations exposed to low levels of ionizing radiation. Responsible public awareness of the possible health effects of ionizing radiations from medical and industrial radiation exposure, centers on three important matters of societal concern: (1) to place into perspective the extent of harm to the health of man and his descendants to be expected in the present and in the future from those societal activities involving ionizing radiation; (2) to develop quantitative indices of harm based on dose-effect relationships; such indices could then be used with prudent caution to introduce concepts of the regulation of population doses on the basis of somatic and genetic risks; and (3) to identify the magnitude and extent of radiation activities which could cause harm, to assess their relative significance, and to provide a framework for recommendations on how to reduce unnecessary radiation exposure to human populations. The main difference of the BEIR Committee Report is not so much from new data or new interpretations of existing data, but rather from a philosophical approach and appraisal of existing and future radiation protection resulting from an atmosphere of constantly changing societal conditions and public attitudes

Radiation therapy induced changes in male sex hormone levels in rectal cancer patients

International Nuclear Information System (INIS)

Dueland, Svein; Groenlie Guren, Marianne; Rune Olsen, Dag; Poulsen, Jan Peter; Magne Tveit, Kjell

2003-01-01

Background and purpose:To determine the effect of curative radiation therapy (46-50 Gy) on the sex hormone levels in male rectal cancer patients. Materials and methods:Twenty-five male rectal cancer patients (mean age 65 years), receiving pelvic radiation therapy (2 Gyx23-25 fractions in 5 weeks) were included. Serum testosterone, FSH and LH were determined before start of treatment, at the 10th and 25th fractions, and 4-6 weeks after completed radiotherapy. The testicular dose was determined by thermoluminescent dosimetry. Results:Five weeks of radiation therapy (46-50 Gy) resulted in a 100% increase in serum FSH, a 70% increase in LH, and a 25% reduction in testosterone levels. After treatment, 35% of the patients had serum testosterone levels below lower limit of reference. The mean radiation dose to the testicles was 8.4 Gy. A reduction in testosterone values was observed already after a mean dose of 3.3 Gy (10th fraction). Conclusion:Radiation therapy (46-50 Gy) for rectal cancer resulted in a significant increase in serum FSH and LH and a significant decrease in testosterone levels, indicating that sex hormone production is sensitive to radiation exposure in patients with a mean age of 65 years

Split energy level radiation detection

International Nuclear Information System (INIS)

Barnes, G.T.

1986-01-01

This patent describes an energy discriminating radiation detector comprising: (a) a first element comprising a first material of a kind which is preferentially responsive to penetrative radiation of a first energy range; (b) a second element comprising a second material different in kind from the first material and of a kind which is preferentially responsive to penetrative radiation of second energy range extending higher than the first energy range. The element is positioned to receive radiation which has penetrated through a portion of the first element; and (c) a filter of penetrative radiation interposed between the first and second elements

Alternative interpretations of statistics on health effects of low-level radiation

International Nuclear Information System (INIS)

Hamilton, L.D.

1983-01-01

Four examples of the interpretation of statistics of data on low-level radiation are reviewed: (a) genetic effects of the atomic bombs at Hiroshima and Nagasaki, (b) cancer at Rocky Flats, (c) childhood leukemia and fallout in Utah, and (d) cancer among workers at the Portsmouth Naval Shipyard. Aggregation of data, adjustment for age, and other problems related to the determination of health effects of low-level radiation are discussed. Troublesome issues related to post hoc analysis are considered

Social economical and psychological considerations in conveying potential radiation risks from high level natural background radiation to the residents of Ramsar, Iran

International Nuclear Information System (INIS)

Mortazavi, S. M. J.; Ghiassi-nejad, M.

2003-01-01

X-rays and radioactivity were discovered more than 100 years ago but the need for protection against very low doses of ionizing radiation and especially different levels of natural radiation is still among the most controversial matters in radiobiology and radiation protection. According to formal reports, some areas in Ramsar, a city in northern Iran, are the inhabited areas with the highest levels of natural radiation studied so far. A population of about 2000 is exposed to average annual radiation levels of 10.2 mGy y''-1 and the highest recorded external gamma dose rates are about 130 mGy y''-1. We have previously shown that in high background radiation areas (HBRAs), cultured human lymphocytes of the inhabitants whose cumulative radiation doses were as much as 170 times more than those of a control area when subjected to 1.5 Gy challenge dose,were significantly more radioresistant compared to the residents of the control area (Mortazavi et al. 2002a,b, Mortazavi and Karam 2002, Ghiassi-Najed et al. 2002). The people who live in these areas are usually unaware of the high levels of natural radiation in their environment. Studies performed on the residents of these areas have indicated that the effective dose of the inhabitants, in some cases, is much higher than the dose limits for occupational irradiation. Considering recent policies of ICRP regarding suggesting dose limits for exposure to natural sources of ionizing including radon, it seems that the inhabitants should become familiar with the possible risks of the exposure to high levels of ionizing radiation. They should also realize that studies performed over the past years have indicated no detrimental effect. On the other hand, according to ICRP suggestions and considering the experiences in other countries, especially evacuation of the residents of contaminated areas after Chernobyl accident, setting any radiation protection regulation for the inhabitants without considering social, economic and

Problem on primary radiation filtration effect on form of coupling equations during X-ray fluorescence analysis

International Nuclear Information System (INIS)

Lavrent'ev, Yu.G.; Kuznetsova, A.I.

1976-01-01

A simplified method for x-ray fluorescence analysis is given. It is shown that the system of coupling equations with constant coefficients and with the number of equations equal to the number of unknown elements allows to obtain the same accuracy of the analysis as with the considerably more complex equations with variable coefficients which take into account the filtration of the primary radiation in a direct way. The system can even be more simplified by using linear equations with constant coefficients. In order to test these systems and to compare them with known coupling equations experimental data for the determination of zirconium and niobium from 16 artificial preparations with fillers of variable composition are presented. The calculation of the absorption of the secondary as well as the primary radiation by means of the proposed equations with constant coefficients is sufficiently good

Assessment of the English literacy level of patients in primary health ...

African Journals Online (AJOL)

... of patients in primary health care services in Tshwane, Gauteng province: Part 2. ... levels of primary health care patients using the Learning Ability Battery (LAB) ... Data were collected by means of a self-report whereby the participants had ...

Topics in radiation at accelerators: Radiation physics for personnel and environmental protection

International Nuclear Information System (INIS)

Cossairt, J.D.

1996-10-01

In the first chapter, terminology, physical and radiological quantities, and units of measurement used to describe the properties of accelerator radiation fields are reviewed. The general considerations of primary radiation fields pertinent to accelerators are discussed. The primary radiation fields produced by electron beams are described qualitatively and quantitatively. In the same manner the primary radiation fields produced by proton and ion beams are described. Subsequent chapters describe: shielding of electrons and photons at accelerators; shielding of proton and ion accelerators; low energy prompt radiation phenomena; induced radioactivity at accelerators; topics in radiation protection instrumentation at accelerators; and accelerator radiation protection program elements

Sunlight-exposed biofilm microbial communities are naturally resistant to chernobyl ionizing-radiation levels.

Directory of Open Access Journals (Sweden)

Marie Ragon

Full Text Available BACKGROUND: The Chernobyl accident represents a long-term experiment on the effects of exposure to ionizing radiation at the ecosystem level. Though studies of these effects on plants and animals are abundant, the study of how Chernobyl radiation levels affect prokaryotic and eukaryotic microbial communities is practically non-existent, except for a few reports on human pathogens or soil microorganisms. Environments enduring extreme desiccation and UV radiation, such as sunlight exposed biofilms could in principle select for organisms highly resistant to ionizing radiation as well. METHODOLOGY/PRINCIPAL FINDINGS: To test this hypothesis, we explored the diversity of microorganisms belonging to the three domains of life by cultivation-independent approaches in biofilms developing on concrete walls or pillars in the Chernobyl area exposed to different levels of radiation, and we compared them with a similar biofilm from a non-irradiated site in Northern Ireland. Actinobacteria, Alphaproteobacteria, Bacteroidetes, Acidobacteria and Deinococcales were the most consistently detected bacterial groups, whereas green algae (Chlorophyta and ascomycete fungi (Ascomycota dominated within the eukaryotes. Close relatives to the most radio-resistant organisms known, including Rubrobacter species, Deinococcales and melanized ascomycete fungi were always detected. The diversity of bacteria and eukaryotes found in the most highly irradiated samples was comparable to that of less irradiated Chernobyl sites and Northern Ireland. However, the study of mutation frequencies in non-coding ITS regions versus SSU rRNA genes in members of a same actinobacterial operational taxonomic unit (OTU present in Chernobyl samples and Northern Ireland showed a positive correlation between increased radiation and mutation rates. CONCLUSIONS/SIGNIFICANCE: Our results show that biofilm microbial communities in the most irradiated samples are comparable to non-irradiated samples in

Sunlight-exposed biofilm microbial communities are naturally resistant to chernobyl ionizing-radiation levels.

Science.gov (United States)

Ragon, Marie; Restoux, Gwendal; Moreira, David; Møller, Anders Pape; López-García, Purificación

2011-01-01

The Chernobyl accident represents a long-term experiment on the effects of exposure to ionizing radiation at the ecosystem level. Though studies of these effects on plants and animals are abundant, the study of how Chernobyl radiation levels affect prokaryotic and eukaryotic microbial communities is practically non-existent, except for a few reports on human pathogens or soil microorganisms. Environments enduring extreme desiccation and UV radiation, such as sunlight exposed biofilms could in principle select for organisms highly resistant to ionizing radiation as well. To test this hypothesis, we explored the diversity of microorganisms belonging to the three domains of life by cultivation-independent approaches in biofilms developing on concrete walls or pillars in the Chernobyl area exposed to different levels of radiation, and we compared them with a similar biofilm from a non-irradiated site in Northern Ireland. Actinobacteria, Alphaproteobacteria, Bacteroidetes, Acidobacteria and Deinococcales were the most consistently detected bacterial groups, whereas green algae (Chlorophyta) and ascomycete fungi (Ascomycota) dominated within the eukaryotes. Close relatives to the most radio-resistant organisms known, including Rubrobacter species, Deinococcales and melanized ascomycete fungi were always detected. The diversity of bacteria and eukaryotes found in the most highly irradiated samples was comparable to that of less irradiated Chernobyl sites and Northern Ireland. However, the study of mutation frequencies in non-coding ITS regions versus SSU rRNA genes in members of a same actinobacterial operational taxonomic unit (OTU) present in Chernobyl samples and Northern Ireland showed a positive correlation between increased radiation and mutation rates. Our results show that biofilm microbial communities in the most irradiated samples are comparable to non-irradiated samples in terms of general diversity patterns, despite increased mutation levels at the single

Sunlight-Exposed Biofilm Microbial Communities Are Naturally Resistant to Chernobyl Ionizing-Radiation Levels

Science.gov (United States)

Ragon, Marie; Restoux, Gwendal; Moreira, David; Møller, Anders Pape; López-García, Purificación

2011-01-01

Background The Chernobyl accident represents a long-term experiment on the effects of exposure to ionizing radiation at the ecosystem level. Though studies of these effects on plants and animals are abundant, the study of how Chernobyl radiation levels affect prokaryotic and eukaryotic microbial communities is practically non-existent, except for a few reports on human pathogens or soil microorganisms. Environments enduring extreme desiccation and UV radiation, such as sunlight exposed biofilms could in principle select for organisms highly resistant to ionizing radiation as well. Methodology/Principal Findings To test this hypothesis, we explored the diversity of microorganisms belonging to the three domains of life by cultivation-independent approaches in biofilms developing on concrete walls or pillars in the Chernobyl area exposed to different levels of radiation, and we compared them with a similar biofilm from a non-irradiated site in Northern Ireland. Actinobacteria, Alphaproteobacteria, Bacteroidetes, Acidobacteria and Deinococcales were the most consistently detected bacterial groups, whereas green algae (Chlorophyta) and ascomycete fungi (Ascomycota) dominated within the eukaryotes. Close relatives to the most radio-resistant organisms known, including Rubrobacter species, Deinococcales and melanized ascomycete fungi were always detected. The diversity of bacteria and eukaryotes found in the most highly irradiated samples was comparable to that of less irradiated Chernobyl sites and Northern Ireland. However, the study of mutation frequencies in non-coding ITS regions versus SSU rRNA genes in members of a same actinobacterial operational taxonomic unit (OTU) present in Chernobyl samples and Northern Ireland showed a positive correlation between increased radiation and mutation rates. Conclusions/Significance Our results show that biofilm microbial communities in the most irradiated samples are comparable to non-irradiated samples in terms of general

Radiation leakage monitoring method and device from primary to secondary coolant systems in nuclear reactor

International Nuclear Information System (INIS)

Tajiri, Yoshiaki; Umehara, Toshihiro; Yamada, Masataka.

1993-01-01

The present invention monitors radiation leaked from any one of primary cooling systems to secondary cooling systems in a plurality of steam generators. That is, radiation monitoring means each corresponding to steam each generators are disposed to the upstream of a position where main steam pipes are joined. With such a constitution, since the detection object of each of radiation monitoring means is secondary coolants before mixing with secondary coolants of other secondary loops or dilution, lowering of detection accuracy can be avoided. Except for the abnormal case, that is, a case neither of radiation leakage nor of background change, the device is adapted as a convenient measuring system only with calculation performance. Once abnormality occurs, a loop having a value exceeding a standard value is identified by a single channel analyzer function. The amount of radiation leakage from the steam generator belonging to the specified loop is monitored quantitatively by a multichannel analyzer function. According to the method of the present invention, since specific spectrum analysis is conducted upon occurrence of abnormality, presence of radiation leakage and the scale thereof can be judged rapidly. (I.S.)

Analysis of radiation level on dinosaur fossil in Zigong

International Nuclear Information System (INIS)

Yang Changshu; Liang Shuzhi; Fan Zhengnian.

1995-01-01

Study on radiation level of dinosaur fossil and environment in conservation zone in Zigong, Sichuan has been done. The results showed that the γ radiation dose and radioactivity strength of 232 Th and 40 K in dinosaur fossil, soil and rock in the conservation zone were within the limits of radioactive background value in Zigong. Radioactivity strength of 238 U, 226 Ra in dinosaur fossil were 26.6 and 29.2 times higher than the rock of same layer respectively

Solar Modulation of Atmospheric Cosmic Radiation:. Comparison Between In-Flight and Ground-Level Measurements

Science.gov (United States)

Iles, R. H. A.; Taylor, G. C.; Jones, J. B. L.

January 2000 saw the start of a collaborative study involving the Mullard Space Science Laboratory, Virgin Atlantic Airways, the Civil Aviation Authority and the National Physical Laboratory in a program to investigate the cosmic radiation exposure to aircrew. The study has been undertaken in view of EU Directive 96/291 (May 2000) which requires the assessment of the level of radiation exposure to aircrew. The project's aims include validation of radiation dose models and evaluation of space weather effects on atmospheric cosmic radiation levels, in particular those effects not accounted for by the models. Ground level measurements are often used as a proxy for variations in cosmic radiation dose levels at aircraft altitudes, especially during Forbush Decreases (FDs) and Solar Energetic Particle (SEP) events. Is this estimation realistic and does the ground level data accurately represent what is happening at altitude? We have investigated the effect of a FD during a flight from Hong Kong to London Heathrow on the 15th July 2000 and compared count rate and dose measurements with simultaneous variations measured at ground level. We have also compared the results with model outputs.

Explaining the absence of Co-58 radiation fields around CANDU reactor primary circuit

International Nuclear Information System (INIS)

Burrill, K.A.; Guzonas, D.A.

2002-01-01

Radiation fields from Co-58 are rarely detected in CANDU plants. For example, Ge(Li) surveys of the Inconel 600 steam generators at some CANDU plants may show radiation attributed to Co-58 only early in plant life, and most artefacts removed from the primary circuit later in plant operation show no Co-58 present. However, Pressurized Water Reactor plants experience relatively large fields from Co-58 on their isothermal piping, e.g., steam generator channel head, and steam generators tube sampling programs do show deposits in the tubes with significant Co-58 compared to other radionuclides such as Co-60. CANDU reactors have high concentrations of dissolved iron due to the extensive use of carbon steel for the isothermal piping, e.g., feeders, headers, and steam generator channel heads. A dissolved iron transport diagram that was proposed recently for the primary circuit of CANDU plants has been validated by comparison of predicted deposit weights with plant deposit data from various components. One feature of the diagram is dissolved iron precipitation inside the steam generators tubes. An hypothesis is advanced here in which precipitating dissolved iron is proposed to occlude dissolved nickel. This removal mechanism may prevent the solubility of dissolved nickel from being exceeded anywhere around the primary circuit. In particular, this mechanism could avoid NiO precipitation in the core and the generation of large quantities of Co-58. Using this mechanism along with the known solubility behaviour of NiO with temperature, a dissolved nickel transport diagram has been proposed for CANDU plants. (authors)

Dual-Energy Micro-Computed Tomography Imaging of Radiation-Induced Vascular Changes in Primary Mouse Sarcomas

Energy Technology Data Exchange (ETDEWEB)

Moding, Everett J. [Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina (United States); Clark, Darin P.; Qi, Yi [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States); Li, Yifan; Ma, Yan [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Ghaghada, Ketan [The Edward B. Singleton Department of Pediatric Radiology, Texas Children' s Hospital, Houston, Texas (United States); Johnson, G. Allan [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States); Kirsch, David G. [Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina (United States); Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Badea, Cristian T., E-mail: cristian.badea@duke.edu [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States)

2013-04-01

Purpose: To evaluate the effects of radiation therapy on primary tumor vasculature using dual-energy (DE) micro-computed tomography (micro-CT). Methods and Materials: Primary sarcomas were generated with mutant Kras and p53. Unirradiated tumors were compared with tumors irradiated with 20 Gy. A liposomal-iodinated contrast agent was administered 1 day after treatment, and mice were imaged immediately after injection (day 1) and 3 days later (day 4) with DE micro-CT. CT-derived tumor sizes were used to assess tumor growth. After DE decomposition, iodine maps were used to assess tumor fractional blood volume (FBV) at day 1 and tumor vascular permeability at day 4. For comparison, tumor vascularity and vascular permeability were also evaluated histologically by use of CD31 immunofluorescence and fluorescently-labeled dextrans. Results: Radiation treatment significantly decreased tumor growth from day 1 to day 4 (P<.05). There was a positive correlation between CT measurement of tumor FBV on day 1 and extravasated iodine on day 4 with microvascular density (MVD) on day 4 (R{sup 2}=0.53) and dextran accumulation (R{sup 2}=0.63) on day 4, respectively. Despite no change in MVD measured by histology, tumor FBV significantly increased after irradiation as measured by DE micro-CT (0.070 vs 0.091, P<.05). Both dextran and liposomal-iodine accumulation in tumors increased significantly after irradiation, with dextran fractional area increasing 5.2-fold and liposomal-iodine concentration increasing 4.0-fold. Conclusions: DE micro-CT is an effective tool for noninvasive assessment of vascular changes in primary tumors. Tumor blood volume and vascular permeability increased after a single therapeutic dose of radiation treatment.

[Internal Exposure Levels of PAHs of Primary School Students in Guangzhou].

Science.gov (United States)

Su, Hui; Zhao, Bo; Zhang, Su-kun; Liu, Shan; Ren, Ming-zhong; Li, Jie; Shi, Xiao-xia

2015-12-01

In order to investigate the internal exposure levels of polycyclic aromatic hydrocarbons (PAHs) in primary school students of Guangzhou, the research collected urine of 78 and 86 primary school students from two primary schools in the summer of 2014, one school located in the ordinary residential area and the other in the industrial area. The contents of 10 kinds of OH-PAHs were tested by the rapid liquid chromatography coupled to triple quadruple tandem mass spectrometry. The results showed that the concentrations of total OH-PAHs in primary school students in the residential zone ranged from 0.83 µmol · mol⁻¹ to 80.63 µmol · mol⁻¹, while those in industrial area ranged from 1.06 µmol · mol⁻¹ to 72.47 µmol · mol⁻¹. The geometric average concentrations were 6.18 µmol · mol⁻¹ and 6.47 µmol · mol⁻¹, respectively, and there was no statistical significance between them (P > 0.05). Comparison of the exposure levels of different components of PAHs in the two areas found that all the OH-PAHs had no significant difference except for the levels of 1- OHP (P transportation emissions.

What happens at very low levels of radiation exposure ? Are the low dose exposures beneficial ?

International Nuclear Information System (INIS)

Deniz, Dalji

2006-01-01

Full text: Radiation is naturally present in our environment and has been since the birth of this planet. The human population is constantly exposed to low levels of natural background radiation, primarily from environmental sources, and to higher levels from occupational sources, medical therapy, and other human-mediated events. Radiation is one of the best-investigated hazardous agents. The biological effects of ionizing radiation for radiation protection consideration are grouped into two categories: The deterministic and the stochastic ones. Deterministic radiation effects can be clinically diagnosed in the exposed individual and occur when above a certain t hreshold a n appropriately high dose is absorbed in the tissues and organs to cause the death of a large number of cells and consequently to impair tissue or organ functions early after exposure. A clinically observable biological effect (Acute Radiation Sendromes, ARS) occurs days to months after an acute radiation dose. Stochastic radiation effects are the chronic effects of radiation result from relatively low exposure levels delivered over long periods of time. These are sort of effects that might result from occupational exposure, or to the background exposure levels. Such late effects might be the development of malignant (cancerous) disease and of the hereditary consequences. These effects may be observed many years after the radiation exposure. There is a latent period between the initial radiation exposure and the development of the biological effect. For this reason, a stochastic effect is called a Linear or Zero-Threshold (LNT) Dose-Response Effect. There is a stochastic correlation between the number of cases of cancers or genetic defects developed inside a population and the dose received by the population at relatively large levels of radiation. These changes in gene activation seem to be able to modify the response of cells to subsequent radiation exposure, termed the a daptive response

Influence of ionizing radiation on gastrointestinal peptide levels

Energy Technology Data Exchange (ETDEWEB)

Wysocki, J.; Esposito, V.; Linard, C. [CEA Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire

1997-03-01

Exposure of the gut to ionising radiation may induce gastrointestinal damage and dysfunction. Early effects such as nausea, vomiting and diarrhea, anorexia may be observed within the first 24 h after irradiation. Such symptoms are seen even with doses as low as 1 Gy. later effects and the onset of the gastrointestinal syndrome are seen at higher doses (10 Gy) and include gastric emptying inhibition, intestinal hemorrhages, disturbances in water and electrolytes balance and septicemia. The severity of which depends on the nature, dose and dose rate received. The mechanism underlying these changes was unclear; it has long been known that exposure to ionising radiation affects intestinal morphology usually because of inhibition of mitotic activity at the level of the crypt enterocyst. The various physiological functions of the gastrointestinal tract are controlled by a wide variety of agents as neurotransmitters, neuropeptides. Radiation induces alterations in hormonal release and response. The present study carried out in the rat focuses on Gastrin Releasing Peptide (GRP), a gastrointestinal neuropeptide present in the central nervous system and in the gut endocrine cells were released into blood. The GRP controls food intake, pancreatic enzyme secretions, gastric emptying, intestinal motility and cellular proliferation. The aim was to investigate the effects of gamma and neutron/gamma on plasma and gastrointestinal tissue levels of GRP

Estimating Net Primary Productivity Beneath Snowpack Using Snowpack Radiative Transfer Modeling and Global Satellite Data

Science.gov (United States)

Barber, D. E.; Peterson, M. C.

2002-05-01

Sufficient photosynthetically active radiation (PAR) penetrates snow for plants to grow beneath snowpack during late winter or early spring in tundra ecosystems. During the spring in this ecosystem, the snowpack creates an environment with higher humidity and less variable and milder temperatures than on the snow-free land. Under these conditions, the amount of PAR available is likely to be the limiting factor for plant growth. Current methods for determining net primary productivity (NPP) of tundra ecosystems do not account for this plant growth beneath snowpack, apparently resulting in underestimating plant production there. We are currently in the process of estimating the magnitude of this early growth beneath snow for tundra ecosystems. Our method includes a radiative transfer model that simulates diffuse and direct PAR penetrating snowpack based on downwelling PAR values and snow depth data from global satellite databases. These PAR levels are convolved with plant growth for vegetation that thrives beneath snowpacks, such as lichen. We expect to present the net primary production for Cladonia species (a common Arctic lichen) that has the capability of photosynthesizing at low temperatures beneath snowpack. This method may also be used to study photosynthesis beneath snowpacks in other hardy plants. Lichens are used here as they are common in snow-covered regions, flourish under snowpack, and provide an important food source for tundra herbivores (e.g. caribou). In addition, lichens are common in arctic-alpine environments and our results can be applied to these ecosystems as well. Finally, the NPP of lichen beneath snowpack is relatively well understood compared to other plants, making it ideal vegetation for this first effort at estimating the potential importance of photosynthesis at large scales. We are examining other candidate plants for their photosynthetic potential beneath snowpack at this time; however, little research has been done on this topic. We

Vessel used in radiation counting to determine radioactivity levels

International Nuclear Information System (INIS)

Charlton, J.C.; Glover, J.S.; Shephard, B.P.

1977-01-01

This invention concerns the vessels used in radiation counting to determine radioactivity levels. These vessels prove to be particularly useful in analyses of the kind where a radioactive element or compound is separated into two phases and the radioactivity of one phase is determined. Such a vessel used in the counting of radiation includes an organic plastic substance tube appreciably cylindrical in shape whose upper end is open whilst the lower end is closed and integral with it, and an anti-radiation shield in metal or in metal reinforced plastic located at the lower end of the tube and extending along the wall of the tube up to a given height. The vessel contains a reaction area of 1 to 10 ml for holding fluid reagents [fr

Coronary cineangiography and ionizing radiation exposure to patients: analysis of primary and secondary beam; Cineangiografia coronaria y radiacion ionizante a pacientes. Analisis en haz primario y secundario

Energy Technology Data Exchange (ETDEWEB)

Ramirez, Alfredo; Leyton, Fernando; Silva, Ana Maria; Farias, Eric [Universidad de Chile, Santiago (Chile). Hospital Clinico; Gamarra, Jorge; Oyarzun, Carlos [Comision Chilena de Energia Nuclear (CCHEN), Santiago (Chile)

2001-07-01

The purpose of this work was to determine the level of exposure dose to patients during coronariographies in different areas of body. This study has presented the medical surveillance of 18 cases and the radiation monitoring of these patients by TLD in thyroid and pelvis (secondary beam) and, in the right and left scapular region (primary beam) for each one of these procedures. The ionizing radiation received was 215 {+-} 200 mGy in left scapular region (range 1-710) and 255{+-}213 mGy in the right scapular region (range 22-635) p=NS. In the pelvic region the ionizing radiation was 0,22{+-}0,06 mGy and in the thyroid region was 3,62{+-}2,44 mGy.

Radiation dose reduction in CT-guided sacroiliac joint injections to levels of pulsed fluoroscopy: a comparative study with technical considerations

Directory of Open Access Journals (Sweden)

Artner J

2012-08-01

Full Text Available Juraj Artner, Balkan Cakir, Heiko Reichel, Friederike LattigDepartment of Orthopaedic Surgery, University of Ulm, RKU, GermanyBackground: The sacroiliac (SI joint is frequently the primary source of low back pain. Over the past decades, a number of different SI injection techniques have been used in its diagnosis and therapy. Despite the concerns regarding exposure to radiation, image-guided injection techniques are the preferred method to achieve safe and precise intra-articular needle placement. The following study presents a comparison of radiation doses, calculated for fluoroscopy and CT-guided SI joint injections in standard and low-dose protocol and presents the technical possibility of CT-guidance with maximum radiation dose reduction to levels of fluoroscopic-guidance for a precise intra-articular injection technique.Objective: To evaluate the possibility of dose reduction in CT-guided sacroiliac joint injections to pulsed-fluoroscopy-guidance levels and to compare the doses of pulsed-fluoroscopy-, CT-guidance, and low-dose CT-guidance for intra-articular SI joint injections.Study design: Comparative study with technical considerations.Methods: A total of 30 CT-guided intra-articular SI joint injections were performed in January 2012 in a developed low-dose mode and the radiation doses were calculated. They were compared to 30 pulsed-fluoroscopy-guided SI joint injections, which were performed in the month before, and to five injections, performed in standard CT-guided biopsy mode for spinal interventions. The statistical significance was calculated with the SPSS software using the Mann–Whitney U-Test. Technical details and anatomical considerations were provided.Results: A significant dose reduction of average 94.01% was achieved using the low-dose protocol for CT-guided SI joint injections. The radiation dose could be approximated to pulsed-fluoroscopy-guidance levels.Conclusion: Radiation dose of CT-guided SI joint injections can be

Practice-level quality improvement interventions in primary care: a review of systematic reviews.

Science.gov (United States)

Irwin, Ryan; Stokes, Tim; Marshall, Tom

2015-11-01

To present an overview of effective interventions for quality improvement in primary care at the practice level utilising existing systematic reviews. Quality improvement in primary care involves a range of approaches from the system-level to patient-level improvement. One key setting in which quality improvement needs to occur is at the level of the basic unit of primary care--the individual general practice. Therefore, there is a need for practitioners to have access to an overview of the effectiveness of quality improvement interventions available in this setting. A tertiary evidence synthesis was conducted (a review of systematic reviews). A systematic approach was used to identify and summarise published literature relevant to understanding primary-care quality improvement at the practice level. Quality assessment was via the Critical Appraisal Skills Programme tool for systematic reviews, with data extraction identifying evidence of effect for the examined interventions. Included reviews had to be relevant to quality improvement at the practice level and relevant to the UK primary-care context. Reviews were excluded if describing system-level interventions. A range of measures across care structure, process and outcomes were defined and interpreted across the quality improvement interventions. Audit and feedback, computerised advice, point-of-care reminders, practice facilitation, educational outreach and processes for patient review and follow-up all demonstrated evidence of a quality improvement effect. Evidence of an improvement effect was higher where baseline performance was low and was particularly demonstrated across process measures and measures related to prescribing. Evidence was not sufficient to suggest that multifaceted approaches were more effective than single interventions. Evidence exists for a range of quality improvement interventions at the primary-care practice level. More research is required to determine the use and impact of quality

Radiation levels at CERN's injectors and their impact on electronic equipment

CERN Document Server

AUTHOR|(SzGeCERN)649218; Brugger, Markus

2013-01-01

Electronic devices operating in hostile radiation environments, such as those found close to high-energy particle accelerators, can suffer from different types of radiation induced failures. At CERN, the mixed particle and energy radiation fields present at the Large Hadron Collider (LHC) and its injector chain can give rise to both stochastic and cumulative effects causing radiation induced failures of exposed electronics and materials, thus directly impacting components and system lifetimes, as well as maintenance requirements. With its original focus on the LHC, the Radiation to Electronics (R2E) project has been successfully implementing mitigation actions in order to avoid accelerator downtime due to radiation induced failures on active electronics. In a next step, the emphasis is put on CERN's injector chain, collecting the respective available information about radiation levels, the definition of additional monitoring requirements and a critical analysis of present and future equipment installations. T...

A flavonoid mutant of barley (Hordeum vulgare L.) exhibits increased sensitivity to UV-B radiation in the primary leaf

International Nuclear Information System (INIS)

Reuber, S.; Bornman, J.F.; Weissenböck, G.

1996-01-01

The aim of the present investigation was to define the role of soluble flavonoids as UV-B protectants in the primary leaf of barley (Hordeum vulgare L.). For this purpose we used a mutant line (Ant 287) from the Carlsberg collection of proanthocyanidin-free barley containing only 7% of total extractable flavonoids in the primary leaf as compared to the mother variety (Hiege 550/75). Seven-day-old leaves from plants grown under high visible light with or without supplementary UV-B radiation were used for the determination of UV-B sensitivity. UV-B-induced changes were assessed from parameters of chlorophyll fluorescence of photosystem II, including initial and maximum fluorescence, apparent quantum yield, and photochemical and non-photochemical quenching. A quartz fibre-optic microprobe was used to evaluate the amount of potentially harmful UV-B (310 nm radiation) penetrating into the leaf as a direct consequence of flavonoid deficiency. Our data indicate an essential role of flavonoids in UV-B protection of barley primary leaves. In leaves of the mutant line grown under supplementary UV-B, an increase in 310nm radiation in the mesophyll and a strong decrease in the quantum yield of photosynthesis were observed as compared to the corresponding mother variety. Primary leaves of liege responded to supplementary UV-B radiation with a 30% increase in the major flavonoid saponarin and a 500% increase in the minor compound lutonarin. This is assumed to be an efficient protective response since no changes in variable chlorophyll fluorescence were apparent. In addition, a further reduction in UV-B penetration into the mesophyll was recorded in these leaves

Environmental policy. Ambient radioactivity levels and radiation doses in 1998

International Nuclear Information System (INIS)

1999-11-01

The report contains information on the natural (background) radiation exposure (chapter II), the natural radiation exposure as influenced by anthropogenic effects (chapter III), the anthropogenic radiation exposure (chapter IV), and the radiation doses to the environment and the population emanating from the Chernobyl fallout (chapter V). The natural radiation exposure is specified referring to the contributions from cosmic and terrestrial background radiation and intake of natural radioactive substances. Changes of the natural environment resulting from anthropogenic effects (technology applications) inducing an increase in concentration of natural radioactive substances accordingly increase the anthropogenic radiation exposure. Indoor air radon concentration in buildings for instance is one typical example of anthropogenic increase of concentration of natural radioactivity, primarily caused by the mining industry or by various materials processing activities, which may cause an increase in the average radiation dose to the population. Measurements so far show that indoor air concentration of radon exceeds a level of 200 Bq/m 3 in less than 2% of the residential buildings; the EUropean Commission therefore recommends to use this concentration value as a maximum value for new residential buildings. Higher concentrations are primarily measured in areas with relevant geological conditions and abundance of radon, or eg. in mining areas. (orig./CB) [de

Differences Between Colon Cancer Primaries and Metastases Using a Molecular Assay for Tumor Radiation Sensitivity Suggest Implications for Potential Oligometastatic SBRT Patient Selection

International Nuclear Information System (INIS)

Ahmed, Kamran A.; Fulp, William J.; Berglund, Anders E.; Hoffe, Sarah E.; Dilling, Thomas J.; Eschrich, Steven A.; Shridhar, Ravi; Torres-Roca, Javier F.

2015-01-01

Purpose: We previously developed a multigene expression model of tumor radiation sensitivity index (RSI) with clinical validation in multiple independent cohorts (breast, rectal, esophageal, and head and neck patients). The purpose of this study was to assess differences between RSI scores in primary colon cancer and metastases. Methods and Materials: Patients were identified from our institutional review board–approved prospective observational protocol. A total of 704 metastatic and 1362 primary lesions were obtained from a de-identified metadata pool. RSI was calculated using the previously published rank-based algorithm. An independent cohort of 29 lung or liver colon metastases treated with 60 Gy in 5 fractions stereotactic body radiation therapy (SBRT) was used for validation. Results: The most common sites of metastases included liver (n=374; 53%), lung (n=116; 17%), and lymph nodes (n=40; 6%). Sixty percent of metastatic tumors, compared with 54% of primaries, were in the RSI radiation-resistant peak, suggesting metastatic tumors may be slightly more radiation resistant than primaries (P=.01). In contrast, when we analyzed metastases based on anatomical site, we uncovered large differences in RSI. The median RSIs for metastases in descending order of radiation resistance were ovary (0.48), abdomen (0.47), liver (0.43), brain (0.42), lung (0.32), and lymph nodes (0.31) (P<.0001). These findings were confirmed when the analysis was restricted to lesions from the same patient (n=139). In our independent cohort of treated lung and liver metastases, lung metastases had an improved local control rate compared to that in patients with liver metastases (2-year local control rate of 100% vs 73.0%, respectively; P=.026). Conclusions: Assessment of radiation sensitivity between primary and metastatic tissues of colon cancer histology revealed significant differences based on anatomical location of metastases. These initial results warrant validation in a larger

Differences Between Colon Cancer Primaries and Metastases Using a Molecular Assay for Tumor Radiation Sensitivity Suggest Implications for Potential Oligometastatic SBRT Patient Selection

Energy Technology Data Exchange (ETDEWEB)

Ahmed, Kamran A. [Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida (United States); Fulp, William J.; Berglund, Anders E. [Department of Biostatistics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida (United States); Hoffe, Sarah E.; Dilling, Thomas J. [Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida (United States); Eschrich, Steven A. [Department of Bioinformatics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida (United States); Shridhar, Ravi [Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida (United States); Torres-Roca, Javier F., E-mail: javier.torresroca@moffitt.org [Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida (United States)

2015-07-15

Purpose: We previously developed a multigene expression model of tumor radiation sensitivity index (RSI) with clinical validation in multiple independent cohorts (breast, rectal, esophageal, and head and neck patients). The purpose of this study was to assess differences between RSI scores in primary colon cancer and metastases. Methods and Materials: Patients were identified from our institutional review board–approved prospective observational protocol. A total of 704 metastatic and 1362 primary lesions were obtained from a de-identified metadata pool. RSI was calculated using the previously published rank-based algorithm. An independent cohort of 29 lung or liver colon metastases treated with 60 Gy in 5 fractions stereotactic body radiation therapy (SBRT) was used for validation. Results: The most common sites of metastases included liver (n=374; 53%), lung (n=116; 17%), and lymph nodes (n=40; 6%). Sixty percent of metastatic tumors, compared with 54% of primaries, were in the RSI radiation-resistant peak, suggesting metastatic tumors may be slightly more radiation resistant than primaries (P=.01). In contrast, when we analyzed metastases based on anatomical site, we uncovered large differences in RSI. The median RSIs for metastases in descending order of radiation resistance were ovary (0.48), abdomen (0.47), liver (0.43), brain (0.42), lung (0.32), and lymph nodes (0.31) (P<.0001). These findings were confirmed when the analysis was restricted to lesions from the same patient (n=139). In our independent cohort of treated lung and liver metastases, lung metastases had an improved local control rate compared to that in patients with liver metastases (2-year local control rate of 100% vs 73.0%, respectively; P=.026). Conclusions: Assessment of radiation sensitivity between primary and metastatic tissues of colon cancer histology revealed significant differences based on anatomical location of metastases. These initial results warrant validation in a larger

Low-level radiation: a review of current estimates of hazards to human populations

International Nuclear Information System (INIS)

Myers, D.K.

1977-12-01

Mankind has always lived with low levels of ionizing radiation from natural sources. This ionizing radiation may induce cancers in irradiated persons and genetic defects in the descendents of irradiated persons. The internationally accepted estimates of risks suggest that the numbers of cancers and genetic defects induced in the general population by natural background radiation are not more than about 1% of the numbers of cancers and genetic defects normally present in the general population. The added risks to the general public due to any prospective nuclear power program are minute compared to those from background radiation. At the maximum permissible levels of radiation exposures for occupational workers, the predicted number of fatal cancers induced would lead to a reduction in average life-span from 73.0 years to about 72.7 years. Since occupational exposures are usually much less than maximum permissible levels, the risks are correspondingly reduced. These occupational risks are comparable to those in most other industries and occupations. Some areas of uncertainty in the accepted risk estimates are discussed in detail in this review. (author)

A Phase I Study of the Combination of Sorafenib With Temozolomide and Radiation Therapy for the Treatment of Primary and Recurrent High-Grade Gliomas

International Nuclear Information System (INIS)

Den, Robert B.; Kamrava, Mitchell; Sheng, Zhi; Werner-Wasik, Maria; Dougherty, Erin; Marinucchi, Michelle; Lawrence, Yaacov R.; Hegarty, Sarah; Hyslop, Terry; Andrews, David W.; Glass, Jon; Friedman, David P.; Green, Michael R.; Camphausen, Kevin; Dicker, Adam P.

2013-01-01

Purpose: Despite recent advances in the management of high-grade and recurrent gliomas, survival remains poor. Antiangiogenic therapy has been shown to be efficacious in the treatment of high-grade gliomas both in preclinical models and in clinical trials. We sought to determine the safety and maximum tolerated dose of sorafenib when combined with both radiation and temozolomide in the primary setting or radiation alone in the recurrent setting. Methods and Materials: This was a preclinical study and an open-label phase I dose escalation trial. Multiple glioma cell lines were analyzed for viability after treatment with radiation, temozolomide, or sorafenib or combinations of them. For patients with primary disease, sorafenib was given concurrently with temozolomide (75 mg/m 2 ) and 60 Gy radiation, for 30 days after completion of radiation. For patients with recurrent disease, sorafenib was combined with a hypofractionated course of radiation (35 Gy in 10 fractions). Results: Cell viability was significantly reduced with the combination of radiation, temozolomide, and sorafenib or radiation and sorafenib. Eighteen patients (11 in the primary cohort, 7 in the recurrent cohort) were enrolled onto this trial approved by the institutional review board. All patients completed the planned course of radiation therapy. The most common toxicities were hematologic, fatigue, and rash. There were 18 grade 3 or higher toxicities. The median overall survival was 18 months for the entire population. Conclusions: Sorafenib can be safely combined with radiation and temozolomide in patients with high-grade glioma and with radiation alone in patients with recurrent glioma. The recommended phase II dose of sorafenib is 200 mg twice daily when combined with temozolomide and radiation and 400 mg with radiation alone. To our knowledge, this is the first publication of concurrent sorafenib with radiation monotherapy or combined with radiation and temozolomide.

Assessing risks from occupational exposure to low-level radiation

International Nuclear Information System (INIS)

Gilbert, E.S.

1989-06-01

Currently, several epidemiological studies of workers who have been exposed occupationally to radiation are being conducted. These include workers in the United States, Great Britain, and Canada, involved in the production of both defense materials and nuclear power. A major reason for conducting these studies is to evaluate possible adverse health effects that may have resulted because of the radiation exposure received. The general subject of health effects resulting from low levels of radiation, including these worker studies, has attracted the attention of various news media, and has been the subject of considerable controversy. These studies provide a good illustration of certain other aspects of the statistician's role; namely, communication and adequate subject matter knowledge. A competent technical job is not sufficient if these other aspects are not fulfilled

Comparison of endotoxin levels found in primary and secondary endodontic infections.

Science.gov (United States)

Gomes, Brenda P F A; Endo, Marcos S; Martinho, Frederico C

2012-08-01

This clinical study was conducted to compare the levels of endotoxins (lipopolysaccharides [LPSs]) found in primary and secondary endodontic infections with apical periodontitis by correlating LPS contents with clinical/radiographic findings. In addition, the presence of target gram-negative anaerobic bacteria was also investigated. Samples were taken from 15 root canals with primary infections and 15 with secondary infections by using paper points. The limulus amebocyte lysate assay was used to quantify endotoxins, and the polymerase chain reaction technique (16S rDNA) was used for bacterial investigation. Endotoxins were detected in 100% of the root canal samples collected from primary (15/15) and secondary (15/15) infections with median values of 7.49 EU/mL and 3.96 EU/mL, respectively (P asymptomatic teeth with primary infections (P 3 mm) (P < .05). Prevotella nigrescens (10/15, 4/15), Fusobacterium nucleatum (5/15, 1/15), Treponema denticola (3/15, 1/15), and Treponema socranskii (5/15, 1/15) were detected in teeth with primary and secondary infections, respectively. P. endodontalis was present only in teeth with primary infections (5/15). Teeth with primary endodontic infections had higher contents of endotoxins and a more complex gram-negative bacterial community than teeth with secondary infections. Moreover, the levels of endotoxins were related to the severity of bone destruction in periapical tissues as well as the development of clinical features in teeth with primary infections. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Validity of the linear no-threshold (LNT) hypothesis in setting radiation protection regulations for the inhabitants in high level natural radiation areas of Ramsar, Iran

International Nuclear Information System (INIS)

Mortazavi, S.M.J.; Atefi, M.; Razi, Z.; Mortazavi Gh

2010-01-01

Some areas in Ramsar, a city in northern Iran, have long been known as inhabited areas with the highest levels of natural radiation. Despite the fact that the health effects of high doses of ionizing radiation are well documented, biological effects of above the background levels of natural radiation are still controversial and the validity of the LNT hypothesis in this area, has been criticized by many investigators around the world. The study of the health effects of high levels of natural radiation in areas such as Ramsar, help scientists to investigate the biological effects without the need for extrapolating the observations either from high doses of radiation to low dose region or from laboratory animals to humans. Considering the importance of these studies, National Radiation Protection Department (NRPD) of the Iranian Nuclear Regulatory Authority has started an integrative research project on the health effects of long-term exposure to high levels of natural radiation. This paper reviews findings of the studies conducted on the plants and humans living or laboratory animals kept in high level natural radiation areas of Ramsar. In human studies, different end points such as DNA damage, chromosome aberrations, blood cells and immunological alterations are discussed. This review comes to the conclusion that no reproducible detrimental health effect has been reported so far. In this paper the validity of LNT hypothesis in the assessment of the health effects of high levels of natural radiation is discussed. (author)

Imaging Primary Mouse Sarcomas After Radiation Therapy Using Cathepsin-Activatable Fluorescent Imaging Agents

Energy Technology Data Exchange (ETDEWEB)

Cuneo, Kyle C. [Department of Radiation Oncology, Duke University School of Medicine, Durham, North Carolina (United States); Mito, Jeffrey K.; Javid, Melodi P. [Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina (United States); Ferrer, Jorge M. [Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts (United States); Kim, Yongbaek [Department of Clinical Pathology, College of Veterinary Medicine, Seoul National University, Seoul (Korea, Republic of); Lee, W. David [The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts (United States); Bawendi, Moungi G. [Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts (United States); Brigman, Brian E. [Department of Orthopedic Surgery, Duke University School of Medicine, Durham, North Carolina (United States); Kirsch, David G., E-mail: david.kirsch@duke.edu [Department of Radiation Oncology, Duke University School of Medicine, Durham, North Carolina (United States); Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina (United States)

2013-05-01

Purpose: Cathepsin-activated fluorescent probes can detect tumors in mice and in canine patients. We previously showed that these probes can detect microscopic residual sarcoma in the tumor bed of mice during gross total resection. Many patients with soft tissue sarcoma (STS) and other tumors undergo radiation therapy (RT) before surgery. This study assesses the effect of RT on the ability of cathepsin-activated probes to differentiate between normal and cancerous tissue. Methods and Materials: A genetically engineered mouse model of STS was used to generate primary hind limb sarcomas that were treated with hypofractionated RT. Mice were injected intravenously with cathepsin-activated fluorescent probes, and various tissues, including the tumor, were imaged using a hand-held imaging device. Resected tumor and normal muscle samples were harvested to assess cathepsin expression by Western blot. Uptake of activated probe was analyzed by flow cytometry and confocal microscopy. Parallel in vitro studies using mouse sarcoma cells were performed. Results: RT of primary STS in mice and mouse sarcoma cell lines caused no change in probe activation or cathepsin protease expression. Increasing radiation dose resulted in an upward trend in probe activation. Flow cytometry and immunofluorescence showed that a substantial proportion of probe-labeled cells were CD11b-positive tumor-associated immune cells. Conclusions: In this primary murine model of STS, RT did not affect the ability of cathepsin-activated probes to differentiate between tumor and normal muscle. Cathepsin-activated probes labeled tumor cells and tumor-associated macrophages. Our results suggest that it would be feasible to include patients who have received preoperative RT in clinical studies evaluating cathepsin-activated imaging probes.

Does the Maternal Serum IgG Level during Pregnancy in Primary Antibody Deficiency Influence the IgG Level in the Newborn?

Directory of Open Access Journals (Sweden)

Vasantha Nagendran

2015-01-01

Full Text Available Purpose. To find out if the serum IgG level in the newborn baby was affected by low maternal serum IgG during pregnancy in two newly diagnosed primary antibody deficient patients. Method. Infant cord blood IgG level was compared with maternal IgG level in 2 mothers with newly diagnosed primary antibody deficiency, who declined replacement IgG treatment during pregnancy. Results. Both mothers delivered healthy babies with normal IgG levels at birth. Conclusions. The normal IgG levels and sound health in these 2 babies in spite of low maternal IgG throughout pregnancy raise interesting discussion points about maternofoetal immunoglobulin transport mechanisms in primary antibody deficiency.

Pulsed radiation decay logging

International Nuclear Information System (INIS)

Mills, W.R. Jr.

1983-01-01

There are provided new and improved well logging processes and systems wherein the detection of secondary radiation is accomplished during a plurality of time windows in a manner to accurately characterize the decay rate of the secondary radiation. The system comprises a well logging tool having a primary pulsed radiation source which emits repetitive time-spaced bursts of primary radiation and detector means for detecting secondary radiation resulting from the primary radiation and producing output signals in response to the detected radiation. A plurality of measuring channels are provided, each of which produces a count rate function representative of signals received from the detector means during successive time windows occurring between the primary radiation bursts. The logging system further comprises means responsive to the measuring channels for producing a plurality of functions representative of the ratios of the radiation count rates measured during adjacent pairs of the time windows. Comparator means function to compare the ratio functions and select at least one of the ratio functions to generate a signal representative of the decay rate of the secondary radiation

Are we at risk from level radiation - DNA repair capacity studies

International Nuclear Information System (INIS)

Riklis, E.; Kol, R.; Heimer, Y.M.

1979-01-01

A new biochemical method, based on determination of DNA repair capability, which will enable predetermination of radiation sensitivity and further - an indication of inherent sensitivity which may be expressed only in the future when a cell will be faced with a situation in which its repair capacity will have to function to its full capability was developed. Cells are treated with trioxalen (trimethylpsoralen, TMP) and near ultraviolet light (NUV), bringing about an almost complete cessation of semiconservative DNA synthesis, 99.5 to 99.8 % inhibition. This method enabled the accurate measurement of incorporation of labelled thymidine into DNA following assaults by radiation or chemicals, indicating that repair synthesis is occurring. The method has been found suitable for the following cells: human fibroblasts, human breast cancer cells, chinese hamster V-79 cells, human lymphocytes. Since the method is applicable also for lymphocytes, it will enable carrying out a world-wide interlaboratory comparative study in which the range of 'repair capacity' of 'normal healthy' humans will be established. Individuals showing no repair capacity will not be permitted to be exposed to any level of radiation above natural background. These are the persons 'at risk' from radiation, while the general public, showing normal repair capacity may be considered safe from the effects of low-level radiations. (B.G.)

Background radiation levels and medical exposure levels in Australia

International Nuclear Information System (INIS)

Webb, D.V.; Solomon, S.B.; Thomson, J.E.M.

1999-01-01

The average effective background dose received by the Australian population has been reassessed to be ∼1.5 millisievert (mSv) per year. Over half of this exposure arises from exposure from terrestrial radiation and cosmic rays, the remainder from radionuclides within the body and from inhalation of radon progeny. This background is to be compared with medical radiation, primarily diagnostic, which could add half as much again to the population exposure. This paper reviews research programmes carried out by the Australian Radiation Laboratory to study radiation exposure from natural background and from medical use. While the latter exposure is accepted to have a social benefit, there is a need to ensure that doses are no more than necessary to provide effective diagnosis and optimal treatment. Copyright (1999) Australasian Radiation Protection Society Inc

Secondary and multiple primary cancers relating radiation therapy for cancer of the oral region

International Nuclear Information System (INIS)

Horiuchi, Junichi; Shibuya, Hitoshi; Takeda, Masamune; Takagi, Minoru.

1985-01-01

Secondary and multiple primary cancers relating radiation therapy for squamous cell carcinoma (s.c.c.) of the oral region including lip, oral cavity and oropharynx were analyzed. Out of 1,197 patients with s.c.c. treated with radiation during about 30 years from 1955 to 1983 June, 56 patients (4.7 %) were regarded as double or multiple cancer. The multiple cancer (s.c.c.) was observed frequently in the multicentric zone such as hypopharynx, esophagus and bronchus as well as in other sites of the oral cavity; 67.7 % (42 out of 62 sites). Frequency of synchronous double cancers was increased in recent ten years; 47.1 % (16/34). Careful examination to the above mentioned multicentric zone leads to early detection of secondary cancer and could be expected cure of the disease. Although possibility of radiation-induced cancer could not be ruled out as for 17 patients with late recurrence (more than 8 years), different histologic diagnosis from s.c.c. was obtained in only one (malignant fibrous histiocytoma). Therefore, it was difficult to discriminate radiation-induced cancer from late recurrence in the present study. (author)

Electromagnetic Radiation Disturbed the Photosynthesis of Microcystis aeruginosa at the Proteomics Level.

Science.gov (United States)

Tang, Chao; Yang, Chuanjun; Yu, Hui; Tian, Shen; Huang, Xiaomei; Wang, Weiyi; Cai, Peng

2018-01-11

Photosynthesis of Microcystis aeruginosa under Electromagnetic Radiation (1.8 GHz, 40 V/m) was studied by using the proteomics. A total of 30 differentially expressed proteins, including 15 up-regulated and 15 down-regulated proteins, were obtained in this study. The differentially expressed proteins were significantly enriched in the photosynthesis pathway, in which the protein expression levels of photosystems II cytochrome b559 α subunit, cytochrome C550, PsbY, and F-type ATP synthase (a, b) decreased. Our results indicated that electromagnetic radiation altered the photosynthesis-related protein expression levels, and aimed at the function of photosynthetic pigments, photosystems II potential activity, photosynthetic electron transport process, and photosynthetic phosphorylation process of M. aeruginosa. Based on the above evidence, that photoreaction system may be deduced as a target of electromagnetic radiation on the photosynthesis in cyanobacteria; the photoreaction system of cyanobacteria is a hypothetical "shared target effector" that responds to light and electromagnetic radiation; moreover, electromagnetic radiation does not act on the functional proteins themselves but their expression processes.

Effects of combined radiofrequency radiation exposure on levels of reactive oxygen species in neuronal cells

International Nuclear Information System (INIS)

Kang, Kyoung Ah; Lee, Hyung Chul; Lee, Je-Jung

2014-01-01

The objective of this study was to investigate the effects of the combined RF radiation (837 MHz CDMA plus 1950 MHz WCDMA) signal on levels of intracellular reactive oxygen species (ROS) in neuronal cells. Exposure of the combined RF signal was conducted at specific absorption rate values of 2 W/kg of CDMA plus 2 W/kg of WCDMA for 2 h. Co-exposure to combined RF radiation with either H 2 O 2 or menadione was also performed. The experimental exposure groups were incubator control, sham-exposed, combined RF radiation-exposed with or without either H 2 O 2 or menadione groups. The intracellular ROS level was measured by flow cytometry using the fluorescent probe dichlorofluorescein diacetate. Intracellular ROS levels were not consistently affected by combined RF radiation exposure alone in a time-dependent manner in U87, PC12 or SH-SY5Y cells. In neuronal cells exposed to combined RF radiation with either H 2 O 2 or menadione, intracellular ROS levels showed no statically significant alteration compared with exposure to menadione or H 2 O 2 alone. These findings indicate that neither combined RF radiation alone nor combined RF radiation with menadione or H 2 O 2 influences the intracellular ROS level in neuronal cells such as U87, PC12 or SH-SY5Y. (author)

Level of knowledge among the population of radiation safety basic issues

Directory of Open Access Journals (Sweden)

S. A. Zelencova

2015-01-01

Full Text Available The goal of research was to determine the level of knowledge among the population on issues like sources of ionising radiation, methods of ionising radiation measurement, measures of self-protection in case of threating or actual radioactive pollution in the district, and to study self-estimation by the population of their knowledge of radiation safety issues. Research was carried out using the method of questioning of population groups in three regions close to the places of previous peaceful nuclear explosions (Arkhangelsk, Murmansk and Tyumen regions, and in five Far East regions of the Russian Federation (Kamchatka, Khabarovsk, Primorsky, Magadan and South-Sakhalin regions after radiation accident in Japan at "Fukushima-1" NPP. This research included processing of 243 questionnaires from the regions close to places of previous peaceful nuclear explosions and 216 questionnaires from the Far East regions.The analysis of obtained questioning results enabled to make the following conclusions: the level of knowledge among the population about the basic concepts of radiation safety appeared to be generally low among respondents of all eight territories. Considerable number of respondents in seven groups correctly mentioned the x-ray device as a source of ionising radiation (from 71 to 88 % of answers. In Murmansk region – only 52 % of the answers. Respondents of the same seven groups often correctly answered the question on how to detect ionising radiation (only with devices – from 68 to 98 % in different groups. The smallest number of correct answers to this question (42 % is also noted among respondents from the Murmansk region.Level of knowledge on self-protection measures at threating or actual radioactive pollution of the places of residence appeared a little higher among the Far East region population, who had actual concerns regarding the threat of radioactive pollution at the present time. However, in all eight investigated groups

Experience in the development and practical use of working control levels for radiation safety

International Nuclear Information System (INIS)

Epishin, A.V.

1981-01-01

The experience of development and practical use of working control levels (WCL) of radiation safety in the Gorky region, is discussed. WCL are introduced by ''Radiation Safety Guides'' (RSG-76) and have great practical importance. Regional control levels of radiation safety are determined for certain types of operations implying radioactive hazard and differentiated according to the types of sources applied and types of operation. Dose rates, radioactive contamination of operating surfaces, skin, air and waste water are subject to normalization. Limits of individual radiation doses specified according to operation categories are included. 10 tables of regional WCL indices are developed [ru

The Australasian radiation protection society's position statement on risks from low levels of ionizing radiation

International Nuclear Information System (INIS)

Don, Higson; Ches, Mason; Andrew, McEwan; Peter, Burns; Riaz, Akber; Ron, Cameron; Pamela, Sykes; Joe, Young

2006-01-01

At its Annual General Meeting in 2004, the Australasian Radiation Protection Society (A.R.P.S.) set up a working group to draft a statement of the Society's position on risks from low levels of exposure to ionizing radiation. The resulting position statement was adopted by the Society at its Annual General Meeting in 2005. Its salient features are as follows: First, there is insufficient evidence to establish a dose-effect relationship for doses that are less than a few tens of milli sieverts in a year. A linear extrapolation from higher dose levels should be assumed only for the purpose of applying regulatory controls. Secondly, estimates of collective dose arising from individual doses that are less than some tens of milli sieverts in a year should not be used to predict numbers of fatal cancers. Thirdly, the risk to an individual of doses significantly less than 100 micro sieverts in a year is so small, if it exists at all, that regulatory requirements to control exposure at this level are not warranted. (authors)

The hazards of low-level radiation

International Nuclear Information System (INIS)

Blackith, R.

1979-01-01

Safety standards are questioned, particularly in relation to the risk of inducing cancer at low doses of radiation. Statements are made on the following topics: incidence of leukaemia among children around reactors, general aging effect due to radiation, leukaemia among radiation workers in a shipyard repairing nuclear submarines, official withdrawal of funds from research workers in the field of radiation hazards, discrepancies between different measurements of radiation near nuclear power plants. (U.K.)

Radiation therapy for primary carcinoma of the female urethra: a survey over 25 years

Energy Technology Data Exchange (ETDEWEB)

Weghaupt, K.; Gerstner, G.J.; Kucera, H.

1984-01-01

Sixty-two patients with primary carcinoma of the female urethra were treated with a combined radiation therapy (high-dose intracavitary vaginal radium and external beam). Treatment was strictly individualized, but an administered tumor dose of 5500-7000 rad (55-70 Gy) was always attempted. Forty-two patients (67.7%) had tumors of the anterior urethra, and in 20 women (32.3%) the posterior urethra was involved. In 19 patients (30.6%) the clinical diagnosis of lymph node involvement was made. The overall 5-year-survival rate was 64.5%. Patients with anterior urethral carcinoma had a higher 5-year-survival rate (71.4%) than patients with posterior carcinoma (50.0%). The favorable results underline the substantial role of radiation therapy for this malignancy.

Radiation therapy for primary carcinoma of the female urethra: a survey over 25 years

International Nuclear Information System (INIS)

Weghaupt, K.; Gerstner, G.J.; Kucera, H.

1984-01-01

Sixty-two patients with primary carcinoma of the female urethra were treated with a combined radiation therapy (high-dose intracavitary vaginal radium and external beam). Treatment was strictly individualized, but an administered tumor dose of 5500-7000 rad (55-70 Gy) was always attempted. Forty-two patients (67.7%) had tumors of the anterior urethra, and in 20 women (32.3%) the posterior urethra was involved. In 19 patients (30.6%) the clinical diagnosis of lymph node involvement was made. The overall 5-year-survival rate was 64.5%. Patients with anterior urethral carcinoma had a higher 5-year-survival rate (71.4%) than patients with posterior carcinoma (50.0%). The favorable results underline the substantial role of radiation therapy for this malignancy

Operator dependency of the radiation exposure in cardiac interventions: feasibility of ultra low dose levels

International Nuclear Information System (INIS)

Emre Ozpelit, Mehmet; Ercan, Ertugrul; Pekel, Nihat; Tengiz, Istemihan; Yilmaz, Akar; Ozpelit, Ebru; Ozyurtlu, Ferhat

2017-01-01

Introduction: Mean radiation exposure in invasive cardiology varies greatly between different centres and interventionists. The International Commission on Radiological Protection and the EURATOM Council stipulate that, despite reference values, 'All medical exposure for radiodiagnostic purposes shall be kept as low as reasonably achievable' (ALARA). The purpose of this study is to establish the effects of the routine application of ALARA principles and to determine operator and procedure impact on radiation exposure in interventional cardiology. Materials and methods: A total of 240 consecutive cardiac interventional procedures were analysed. Five operators performed the procedures, two of whom were working in accordance with ALARA principles (Group 1 operators) with the remaining three working in a standard manner (Group 2 operators). Radiation exposure levels of these two groups were compared. Results: Total fluoroscopy time and the number of radiographic runs were similar between groups. However, dose area product and cumulative dose were significantly lower in Group 1 when compared with Group 2. Radiation levels of Group 1 were far below even the reference levels in the literature, thus representing an ultra-low-dose radiation exposure in interventional cardiology. Conclusion: By use of simple radiation reducing techniques, ultra-low-dose radiation exposure is feasible in interventional cardiology. Achievability of such levels depends greatly on operator awareness, desire, knowledge and experience of radiation protection. (authors)

Effect of radiation on microbiologic characteristics of M. tuberculosis

International Nuclear Information System (INIS)

Zack, M.B.; Stottmeier, K.; Berg, G.; Kazemi, H.

1974-01-01

The effect of irradiation on mutation (expressing itself as drug resistance) and on viability of Mycobacterium tuberculosis was studied in vitro. Forty-two identical cultures of H37-Rv (M. tuberculosis) were exposed to different levels of cobalt radiation (10, 100, 1,000, 2,500, 5,000, 10,000, and 20,000 rads) with six samples used for each of the seven radiation levels. Equivalent samples exposed to zero rads and samples handled and stored identically formed the controls. Coded cultures were read in a double-blind fashion to determine the number of surviving organisms and sensitivities to nine different antituberculosis drugs. Organism viability began to decrease at radiation levels of 1,000 rads and decreased linearly with higher levels of radiation. Three of the 42 radiated cultures developed drug-resistant organisms (one to INH, one to PAS, a third to SM). This drug resistance occurred at levels of clinical significance (greater than 1 percent control) as well as in amounts exceeding probability values for chance resistance mutation. High radiation levels such as occur in radiotherapeutic doses decrease the viability of M. tuberculosis. Radiation may also induce genetic mutation expressed as primary drug resistance. (U.S.)

1991 implementation of As Low As Reasonably Achievable (ALARA) administrative radiation exposure levels: Experiences and lessons learned

International Nuclear Information System (INIS)

Aldridge, T.L.; Baumann, B.L.

1993-06-01

As Low As Reasonably Achievable (ALARA) radiation exposure levels were implemented on January 1, 1991, by Westinghouse Hanford Company (WHC), a prime US Department of Energy (DOE) contractor, located in Richland, Washington. This paper describes the radiation exposure levels which were implemented and the associated experiences and lessons learned. The issue of a report from the Committee on Biological Effectiveness of Ionizing Radiation in 1989 prompted DOE to re-evaluate its position on radiation exposure limits and the resulting doses received by occupational radiation workers. DOE requested that all it's contractors determine the impacts to operations from reduced radiation exposure levels

Radiation chemistry

International Nuclear Information System (INIS)

Rodgers, F.; Rodgers, M.A.

1987-01-01

The contents of this book include: Interaction of ionizing radiation with matter; Primary products in radiation chemistry; Theoretical aspects of radiation chemistry; Theories of the solvated electron; The radiation chemistry of gases; Radiation chemistry of colloidal aggregates; Radiation chemistry of the alkali halides; Radiation chemistry of polymers; Radiation chemistry of biopolymers; Radiation processing and sterilization; and Compound index

Prognostic threshold levels of NT-proBNP testing in primary care

DEFF Research Database (Denmark)

Rosenberg, J.; Schou, M.; Gustafsson, F.

2008-01-01

AIMS: Chronic heart failure (HF) is a common condition with a poor prognosis. As delayed diagnosis and treatment of HF patients in primary care can be detrimental, risk-stratified waiting lists for echocardiography might optimize resource utilization. We investigated whether a prognostic threshold...... level of the cardiac peptide, NT-proBNP, could be identified. METHODS AND RESULTS: From 2003-2005, 5875 primary care patients with suspected HF (median age 73 years) had NT-proBNP analysed in the Copenhagen area. Eighteen percent died and 20% had a cardiovascular (CV) hospitalization (median follow....../mL) was associated with an 80% (95% CI: 20-190, P = 0.01) increased mortality risk after adjustment for age, sex, previous hospitalization, CV diseases, and chronic diseases. CONCLUSION: We identified prognostic threshold levels for mortality and CV hospitalization for NT-proBNP in primary care patients suspected...

PERCEPTION LEVEL EVALUATION OF RADIO ELECTRONIC MEANS TO A PULSE OF ELECTROMAGNETIC RADIATION

Directory of Open Access Journals (Sweden)

2016-01-01

Full Text Available The method for evaluating the perception level of electronic means to pulsed electromagnetic radiation is consid- ered in this article. The electromagnetic wave penetration mechanism towards the elements of electronic systems and the impact on them are determined by the intensity of the radiation field on the elements of electronic systems. The impact of electromagnetic radiation pulses to the electronic systems refers to physical and analytical parameters of the relationship between exposure to pulses of electromagnetic radiation and the sample parameters of electronic systems. A physical and mathematical model of evaluating the perception level of electronic means to pulsed electromagnetic radiation is given. The developed model was based on the physics of electronics means failure which represents the description of electro- magnetic, electric and thermal processes that lead to the degradation of the original structure of the apparatus elements. The conditions that lead to the total equation electronic systems functional destruction when exposed to electromagnetic radia- tion pulses are described. The internal characteristics of the component elements that respond to the damaging effects are considered. The ratio for the power failure is determined. A thermal breakdown temperature versus pulse duration of expo- sure at various power levels is obtained. The way of evaluation the reliability of electronic systems when exposed to pulses of electromagnetic radiation as a destructive factor is obtained.

Long term results of primary radiation therapy for squamous cancer of the base of tongue

International Nuclear Information System (INIS)

Harrison, LB; Lee, H; Kraus, DH; Zelefsky, M; Strong, EW; Pfister, DG; Raben, A; Shah, J; White, C; Carper, E; Portenoy, R

1996-01-01

From 1981-1995, 68 patients with primary squamous cell cancer of the base of tongue were managed with primary radiation therapy, with neck dissection added for those who presented with palpable lymph node metastases. Ages ranged from 35-77 (median 55). There were 59 males and 9 females. T Stage was: T1-17, T2-32, T3-17, T4-2. Fifty-eight patients (85%) presented with nodal metastases. Treatment generally involved external beam radiation (EBRT) to the primary site and upper neck (54 Gy), low neck (50 Gy), additional EBRT to area of nodal involvement to 60 Gy, followed (2-4 weeks later) by brachytherapy boost (20-30 Gy) to the base of tongue using Iridium-192. The implant was done at the same anesthesia as the neck dissection, and all patients had temporary tracheostomy. Follow-up ranges from 1-151 months (median 36 months). Nine patients received neo-adjuvant chemotherapy. Actuarial 5 and 10-year local control is 88% and 88%, regional control is 96% and 96%, distant metastasis free survival is 91% and 76%, disease free survival is 80% and 67%, and overall survival is 86% and 52%, respectively. After EBRT, 78% of dissected necks were pathologically negative. Complications occurred in 16%. A detailed quality of life (QOL) assessment has been completed on the first 36 patients with a minimum follow-up of 3 years, and median follow-up of 5 years. This included a Performance Status Assessment, socio-demographic and economic questionnaire, a multidimensional QOL assessment measuring emotional, physical, social and functional well-being, and the Memorial Symptom Assessment Scale. This data will be presented. The overwhelming majority of patients were able to maintain their pre-diagnosis earning potential, employment status, speaking ability and ability to eat in public. However, a variety of symptoms such as xerostomia, swallowing difficulty, decreased energy, changes in taste and dietary restrictions were observed. Our data shows that primary radiation therapy produces

Radiation Therapy in the Management of Head-and-Neck Cancer of Unknown Primary Origin: How Does the Addition of Concurrent Chemotherapy Affect the Therapeutic Ratio?

International Nuclear Information System (INIS)

Chen, Allen M.; Farwell, D. Gregory; Lau, Derick H.; Li Baoqing; Luu, Quang; Donald, Paul J.

2011-01-01

Purpose: To determine how the addition of cisplatin-based concurrent chemotherapy to radiation therapy influences outcomes among a cohort of patients treated for head-and-neck cancer of unknown primary origin. Methods and Materials: The medical records of 60 consecutive patients treated by radiation therapy for squamous cell carcinoma of the head and neck presenting as cervical lymph node metastasis of occult primary origin were reviewed. Thirty-two patients (53%) were treated by concurrent chemoradiation, and 28 patients (47%) were treated by radiation therapy alone. Forty-five patients (75%) received radiation therapy after surgical resection, and 15 patients (25%) received primary radiation therapy. Thirty-five patients (58%) were treated by intensity-modulated radiotherapy. Results: The 2-year estimates of overall survival, local-regional control, and progression-free survival were 89%, 89%, and 79%, respectively, among patients treated by chemoradiation, compared to 90%, 92%, and 83%, respectively, among patients treated by radiation therapy alone (p > 0.05, for all). Exploratory analysis failed to identify any subset of patients who benefited from the addition of concurrent chemotherapy to radiation therapy. The use of concurrent chemotherapy was associated with a significantly increased incidence of Grade 3+ acute and late toxicity (p < 0.001, for both). Conclusions: Concurrent chemoradiation is associated with significant toxicity without a clear advantage to overall survival, local-regional control, and progression-free survival in the treatment of head-and-neck cancer of unknown primary origin. Although selection bias cannot be ignored, prospective data are needed to further address this question.

Developing a framework to model the primary drying step of a continuous freeze-drying process based on infrared radiation

DEFF Research Database (Denmark)

Van Bockstal, Pieter-Jan; Corver, Jos; Mortier, Séverine Thérèse F.C.

2018-01-01

. These results assist in the selection of proper materials which could serve as IR window in the continuous freeze-drying prototype. The modelling framework presented in this paper fits the model-based design approach used for the development of this prototype and shows the potential benefits of this design...... requires the fundamental mechanistic modelling of each individual process step. Therefore, a framework is presented for the modelling and control of the continuous primary drying step based on non-contact IR radiation. The IR radiation emitted by the radiator filaments passes through various materials...

Level of terrestrial gamma radiation and doses to population in Jiangsu province

International Nuclear Information System (INIS)

1985-01-01

In this paper the results of investigation of terrestrial gamma radiation level in Jiangsu Province are reported and the population doses due to this radiation are estimated. The sketch map of the geographical distribution of the terrestrial gamma radiation level is given. In this investigation FD-71 portable scintillation counters and RSS-111 high pressure ionization chambers were used. The results showed that the terrestrial gamma absorbed dose rates in air for indoors and outdoors were 10.7 x 10 -8 Gy/h and 6.5 x 10 -8 Gy/h (weighted values) respectively. The indoors-to-outdoors ratio was 1.65. The total (indoor plus outdoor) annual effective dose equivalent from terrestrial gamma radiation, averaged over the population in this province, was 6.0 x 10 -4 Sv. The collective annual effective dose equivalent was 3.6 x 10 4 man.Sv. Therefore, the absorbed dose to population in Jiangsu Province is in the range of the normal background

Radiation-induced bilateral cystic frontal lobe necroses demonstrating a fluid-blood level; Case report

Energy Technology Data Exchange (ETDEWEB)

Mineura, Katsuyoshi; Sasajima, Toshio; Kowada, Masayoshi [Akita Univ. (Japan). School of Medicine; Ogawa, Toshihide

1992-02-01

A 41-year-old male developed radiation-induced bilateral cystic frontal lobe necroses after irradiation for an olfactory neuroblastoma. Computed tomography (CT) and magnetic resonance (MR) imaging revealed the lesions, one containing a fluid-blood level on CT scans and niveau formation on MR images. It was proved to be a coagulated hematoma within the cyst at surgery. Such a fluid-blood level in a radiation-induced cyst has never been reported, although hemorrhage frequently accompanies delayed radiation necrosis. Positron emission tomography with multiple tracers may be useful in differentiating cerebral radiation necrosis from tumor recurrence, because of absence of abnormal tracer accumulation. (author).

Impact of low-level radiation with special reference to tritium in environment

International Nuclear Information System (INIS)

Bhatia, A.L.

2005-01-01

Radiation is invisible, but exists in various types, in the form of particles and/or energy bundles. The effects of low-level radiation seem very abstract since these can not be perceived by our sensory organs. The increase in natural background radiation from various inadvertent sources like tritium has the prospect of altering the entire scenario of billions of years' slow and steady biogenetic evolution. Mankind, by developing atomic technologies, is unleashing forces which it does understand but not beyond experimental findings. There is no wise sorcerer who can undo the damage we are causing. Tritium is a radioactive form of hydrogen that is produced in the reactor core. The released tritium replaces hydrogen in water. Tritium in water when gets ingested, causes continuos internal low-level beta radiation exposure over a long period. Proposed presentation will focus on the possible long term damage caused by its low-level exposure is dependent on the length of duration living tissue spends in the radiation field, not on the relative radiation field strength. As internal radiation pulses never stop, impact is continuous by the ambient radiation atmosphere. There is no chance to heal at the molecular level, except small chances of DNA repair since the organically bound tritium has greater severe influence with the slow turnover. Though the situation needs not be alarming with tritium, the studies on radiation damage on various parameters have given evidence of two compartments of radiation damage; the reparable or potentially lethal and the irreparable or lethal. With emerging new reports on the stochastic effects, those for which the probability, rather than the severity of an effect from tritium occurring as a function of dose also can not be ruled out. Biotoxicity of tritium in the form of induction of cancer, hereditary effects, teratogenesis and life shortening really needs an exhaustive investigation and warrants careful evaluation. However, a positive

The need for the use of high-level radiation in water treatment and in waste-water (sewage) treatment

International Nuclear Information System (INIS)

Nielson, N.E.

1975-01-01

After excellent conventional primary, followed by the best possible conventional aerobic secondary and then chemical disinfection, significant quantities of contaminants are still present in sewage, especially pathogenic organisms and toxic or toxicity-causing long-chain-molecular forms. These contaminants are generally encountered in waste-waters with a seldom predictable, almost totally random frequency. Many of these chemical forms enter re-use situations where they can become toxic to man, or to wildlife, even in concentrations of a few parts per thousand million. It has been amply demonstrated that the long-held contention is no longer valid that dilution of these contaminants to an innocuous level is easily attained by their release into large bodies of water such as lakes, oceans and rivers. At the same time, a great deal of energy is required when using known techniques in highly reliable systems for removing or rendering innocuous a large portion of these contaminants. In the light of this new (to some people) information describing a much larger, more complex set of conditions which must be considered in effective water pollution elimination, high-level radiation becomes very attractive. There is a great need for high-level radiation in water treatment or waste-water treatment where the ultimate goal is a safe, clean, non-environmentally degrading, safely re-usable quality of water. Gamma radiation, used under the right circumstances, is the most reliable, most cost-effective, most generally efficient technique in the tertiary stages. With the addition of select chemicals to increase the number of ionizations realized and/or to capitalize upon surface charge phenomena, its effectiveness can be even further expanded. (author)

Comparison of Reading Levels of Pharmacy Students and Reading Level of Primary Literature

Directory of Open Access Journals (Sweden)

Cathy H Ficzere

2016-09-01

Full Text Available Objectives: The project purpose was to evaluate pharmacy students’ reading levels using the Nelson-Denney Reading Test (NDRT and compare these results with the reading level of primary literature to investigate incongruities between student’s comprehension ability and the readability level of assigned reading in the curriculum. Methods: The NDRT was administered to first- through third-year student pharmacists to determine grade equivalents (GE for vocabulary and reading comprehension. Twenty articles previously identified as Patient-Oriented Evidence that Matters (POEMs were analyzed to determine the Flesch-Kincaid Grade Level and Gunning-Fog Score. Student demographics, information regarding language spoken, and reading habits, were also assessed. Pearson product moment correlations, t-tests, ANOVA, and descriptive statistics were used to assess relationships between demographic data and NDRT scores. Results: One hundred students participated. The mean NDRT total grade equivalent (±SD was 16.95 ± 2.1 (median = 17.3. NDRT grade equivalents were statistically different for students with different racial or ethnic backgrounds (t(98=3.74, p=0.026, English as a second language (ESL students (t(98=5.19, p=0.021, and students that read works of fiction for pleasure (t(98=4.31, p=0.002. The average Gunning-Fog Score for all primary literature articles was 11.48, with the introduction section being the most complex. The average Flesch-Kincaid Grade Level was 17.04, with the results section scoring the lowest average grade level. Implications: While the overall reading grade level of our pharmacy students suggests that they are capable of comprehending reading assigned in the pharmacy curriculum, minority students and students for whom English is a second language may struggle with comprehending complex text. Conflict of Interest We declare no conflicts of interest or financial interests that the authors or members of their immediate families have

Role of Definitive Radiation Therapy in Carcinoma of Unknown Primary in the Abdomen and Pelvis

International Nuclear Information System (INIS)

Kelly, Patrick; Das, Prajnan; Varadhachary, Gauri R.; Fontanilla, Hiral P.; Krishnan, Sunil; Delclos, Marc E.; Jhingran, Anuja; Eifel, Patricia J.; Crane, Christopher H.

2012-01-01

Objectives: Carcinoma of unknown primary (CUP) in the abdomen and pelvis is a heterogeneous group of cancers with no standard treatment. Considered by many to be incurable, these patients are often treated with chemotherapy alone. In this study, we determined the effectiveness of radiation therapy in combination with chemotherapy in patients with CUP in the abdomen and pelvis. Patients and Methods: Medical records were reviewed for 37 patients with CUP treated with radiation therapy for disease located in the soft tissues and/or nodal basins of the abdomen and pelvis at University of Texas M.D. Anderson Cancer between 2002 and 2009. All patients underwent chemotherapy, either before or concurrent with radiation therapy. Patients were selected for radiation therapy on the basis of histologic type, disease extent, and prior therapy response. Twenty patients underwent definitive radiation therapy (defined as radiation therapy targeting all known disease sites with at least 45 Gy) and 17 patients underwent palliative radiation therapy. Only 6 patients had surgical resection of their disease. Patient and treatment characteristics were extracted and the endpoints of local disease control, progression-free survival (PFS), overall survival (OS), and treatment-related toxicity incidence were analyzed. Results: The 2-year PFS and OS rates for the entire cohort were 32% and 57%, respectively. However, in patients treated with definitive radiation therapy, the rates were 48% and 76%, and 7 patients lived more than 3 years after treatment with no evidence of disease progression. Nevertheless, radiation-associated toxicity was significant in this cohort, as 40% experienced Grade 2 or higher late toxicities. Conclusions: The use of definitive radiation therapy should be considered in selected patients with CUP in the soft tissues or nodal basins of the abdomen and pelvis.

The assessment of risks from exposure to low-levels of ionizing radiation

International Nuclear Information System (INIS)

Gilbert, E.S.

1992-06-01

This report is concerned with risk assessments for human populations receiving low level radiation doses; workers routinely exposed to radiation, Japanese victims of nuclear bombs, and the general public are all considered. Topics covered include risk estimates for cancer, mortality rates, risk estimates for nuclear site workers, and dosimetry

Natural radiation external exposures levels in Chilean Sub-Antarctic and country stations

International Nuclear Information System (INIS)

Stuardo, E.

1988-01-01

Since 1983 gamma exposures levels, at 1,5 m above the soil are being investigated using TLD detectors. A network of 12 stations have been established from ARICA (18 deg 20' S latitude) in Northern Chile to YELCHO (64 deg 52' S latitude) in Antartic territory. One year monitoring period was used at Antartic stations and a four months period in the country. The main subject of this study is to assess the average background radiation levels along the territory which is relevant to get a reference level and specially an estimate of the average natural radiation contribution to the population dose in Southern Chile

Ambient radioactivity levels and radiation doses. Annual report 2014; Umweltradioaktivitaet und Strahlenbelastung. Jahresbericht 2014

Energy Technology Data Exchange (ETDEWEB)

Trugenberger-Schnabel, Angela; Loebke-Reinl, Angelika; Peter, Josef (comps.) [Bundesamt fuer Strahlenschutz, Salzgitter (Germany)

2016-08-15

The annual report 2014 on ambient radioactivity levels and radiation doses covers the following topics: (1) Actual data and their evaluation: natural environmental radioactivity, artificial environmental radioactivity, occupational radiation exposure, radiation exposures from medical applications, handling of radioactive materials and sources of ionizing radiation, non-ionizing radiation. (2) Fundamentals and general information: legal basis and explanations, basic information on natural environmental radioactivity, basic information on artificial radioactivity in the environment, basic information on occupational radiation exposure, basic information on radiation exposures from medical applications, basic information on the handling of radioactive materials and sources of ionizing radiation, basic information on non-ionizing radiation. (3) Tables.

High level natural radiation areas with special regard to Ramsar

International Nuclear Information System (INIS)

Sohrabi, M.

1993-01-01

The studies of high level natural radiation areas (HLNRAs) around the world are of great importance for determination of risks due to long-term low-level whole body exposures of public. Many areas of the world possess HLNRAs the number of which depends on the criteria defined. Detailed radiological studies have been carried out in some HLNRAs the results of which have been reported at least in three international conferences. Among the HLNRAs, Ramsar has so far the highest level of natural radiation in some areas where radiological studies have been of concern. A program was established for Ramsar and its HLNRAs to study indoor and outdoor gamma exposures and external and internal doses of the inhabitants, 226 Ra content of public water supplies and hot springs, of food stuffs, etc., 222 Rn levels measured in 473 rooms of near 350 houses, 16 schools and 89 rooms and many locations of old and new Ramsar Hotels in different seasons, cytogenetic effects on inhabitants of Talesh Mahalleh, the highest radiation area, compared to that of a control area and radiological parameters of a house with a high potential for internal and external exposures of the inhabitants. It was concluded that the epidemiological studies in a number of countries did not show any evidence of increased health detriment in HLNRAs compared to control groups. In this paper, the conclusions drawn from studies in some HLNRAs around the world in particular Ramsar are discussed. (author). 20 refs, 2 figs, 1 tab

Ramsar hot springs: how safe is to live in an environment with high level of natural radiation

International Nuclear Information System (INIS)

Mortazavi, S.M.J.

2005-01-01

Ramsar in northern Iran is among the world's well-known areas with highest levels of natural radiation. Annual exposure levels in areas with elevated levels of natural radiation in Ramsar are up to 260 mGy y -1 and average exposure rates are about 10 mGy y -1 for a population of about 2000 residents. Due to the local geology, which includes high levels of radium in rocks, soils, and groundwater, Ramsar residents are also exposed to high levels of alpha activity in the form of ingested radium and radium decay progeny as well as very high radon levels (over 1000 MBq m -3 ) in their dwellings. In some cases, the inhabitants of these areas receive doses much higher than the current ICRP-60 dose limit of 20 mSv y -1 . As the biological effects of low doses of radiation are not fully understood, the current radiation protection recommendations are based on the predictions of an assumption on the linear, no-threshold (LNT) relationship between radiation dose and the carcinogenic effects. Considering LNT, areas having such levels of natural radiation must be evacuated or at least require immediate remedial actions. Inhabitants of the high level natural radiation areas (HLNRAs) of Ramsar ar largely unaware of natural radiation, radon, or its possible health effects, and the inhabitants have not encountered any harmful effects due to living in their paternal houses. In this regard, it is often difficult to ask the inhabitants of HLNRAs of Ramsar to carry out remedical actions. Despite the fact that considering LNT and ALARA, public health in HLNRAs like Ramsar is best served by relocating the inhabitants, the residents' health seems unaffected and relocation is upsetting to the residents. Based on the findings obtained by studies on the health effect of high levels of natural radiation in Ramsar, as well as other HLNRAs, no consistent detrimental effect has been detected so far. However, more research is needed to clarify if the regulatory authorities should set limiting

Investigation on the acceptance level of radiation exposure. Comparison of Chinese and Japanese

International Nuclear Information System (INIS)

Wu, Jin; Katoh, Kazuaki

1999-01-01

Radiation has helped to develop our culture and civilization, both of material and of spiritual, and without doubt it is useful to develop our civilization further and to enrich our future life. On the other hand, we cannot help avoiding to live with some by-product radiation of 'advanced civilization' in addition. Thus we must associate with radiation even if we like it or not. To our understanding, safety standard or criteria of safety control is nothing but a contract of the body concerned with the society. In order to make this contract rigorously, it is required for both sides to have adequately enough knowledge and data on the methodology of treating the matter. In such societies, people's acceptable levels to radiation exposure would not be widely distributed. Unification of the wills of the society is absolutely necessary to establish such a contact or develop the philosophy on radiation safety. Hence, we have tried to investigate the acceptable levels of people to radiation exposure. Two kinds of levels, upper limit of the acceptable dose for instantaneous whole body exposure, Lu, and lowest of the dose caring in mind, Ll, were set for inquiry. In this presentation, some results of our survey to both Chinese and Japanese professionals in the fields of science-technology and medical science are reported. Similarly to the previous study by Katoh, in 1989 or so, the distribution of these two levels were very broad and the band widths between the two levels, Lu and Ll, were quite narrow. The former seems reveal the variety of individual's sense of value. Moreover, it was found that, two levels, Lu and Ll, were significantly higher (p<0.05, p<0.005) in Japanese to in Chinese in science/engineering group, while in medical group, the two levels were higher apparently in Japanese than in Chinese, but no statistically significant difference was observed. Moreover, in medical group, Lu and Ll showed higher values than those in science-technology group for the

Radiation sources, radiation environment and risk level at Dubna

International Nuclear Information System (INIS)

Komochkov, M.M.

1991-01-01

The overall information about ionizing radiation sources, which form radiation environment and risk at Dubna, is introduced. Systematization of the measurement results is performed on the basis of the effective dose and losses of life expectancy. The contribution of different sources to total harm of Dubna inhabitants has been revealed. JINR sources carry in ∼ 4% from the total effective dose of natural and medicine radiation sources; the harm from them is much less than the harm from cigarette smoking. 18 refs.; 2 tabs

Legal aspects of radiation protection at the international level

International Nuclear Information System (INIS)

Papazian, J.

1981-01-01

A review is made of the respective activities of the various international organizations concerned with radiation protection at the legal level. These organizations are either non-governmental (I.C.R.P., I.C.R.U.) or governmental in which case they can act at the world (U.N., I.A.E.A., I.L.O., W.H.O.) or regional level (N.E.A., EURATOM, COMECOM). The legal impact of the recommendations or directives they issue is specified [fr

Epidemiological studies of general population groups exposed to low-level radiation

International Nuclear Information System (INIS)

Davies, J.M.; Inskip, H.

1986-01-01

The exposure of man to radiation and the resulting risk of carcinogenesis continue to be of concern to the public. In this context, there is often a tendency to carry out epidemiological studies concerning the induction of cancer in radiation workers and members of the public which are not supported by a statistically valid data base or whose result are misinterpreted or misused. To assist national authorities in evaluating radiological risks, the Nuclear Energy Agency has sponsored a critical review of the methodologies for, and the limitations of, these epidemiological studies, and of the precautions to be adopted in interpreting their results. Prepared by two consultants, Dr. Joan M. Davies and Dr. Hazel Inskip, the review focuses on the problems encountered when carrying out epidemiological studies on groups of the general population exposed to radiation, and using their results for radiological protection purposes. The primary objective is to provide background material for national authorities who have responsibilities in the field of radiological protection, as well as to other persons interested in this subject. It is published under the responsibility of the Secretary General of the OECD, and does not necessarily reflect the views of Member Governments

Bystander-mediated genomic instability after high LET radiation in murine primary haemopoietic stem cells

International Nuclear Information System (INIS)

Bowler, Deborah A.; Moore, Stephen R.; Macdonald, Denise A.; Smyth, Sharon H.; Clapham, Peter; Kadhim, Munira A.

2006-01-01

Communication between irradiated and unirradiated (bystander) cells can result in responses in unirradiated cells that are similar to responses in their irradiated counterparts. The purpose of the current experiment was to test the hypothesis that bystander responses will be similarly induced in primary murine stem cells under different cell culture conditions. The experimental systems used here, co-culture and media transfer, are similar in that they both restrict communication between irradiated and bystander cells to media borne factors, but are distinct in that with the media transfer technique, cells can only communicate after irradiation, and with co-culture, cells can communication before, during and after irradiation. In this set of parallel experiments, cell type, biological endpoint, and radiation quality and dose, were kept constant. In both experimental systems, clonogenic survival was significantly decreased in all groups, whether irradiated or bystander, suggesting a substantial contribution of bystander effects (BE) to cell killing. Genomic instability (GI) was induced under all radiation and bystander conditions in both experiments, including a situation where unirradiated cells were incubated with media that had been conditioned for 24 h with irradiated cells. The appearance of delayed aberrations (genomic instability) 10-13 population doublings after irradiation was similar to the level of initial chromosomal damage, suggesting that the bystander factor is able to induce chromosomal alterations soon after irradiation. Whether these early alterations are related to those observed at later timepoints remains unknown. These results suggest that genomic instability may be significantly induced in a bystander cell population whether or not cells communicate during irradiation

Radiation therapists' perceptions of the minimum level of experience required to perform portal image analysis

International Nuclear Information System (INIS)

Rybovic, Michala; Halkett, Georgia K.; Banati, Richard B.; Cox, Jennifer

2008-01-01

Background and purpose: Our aim was to explore radiation therapists' views on the level of experience necessary to undertake portal image analysis and clinical decision making. Materials and methods: A questionnaire was developed to determine the availability of portal imaging equipment in Australia and New Zealand. We analysed radiation therapists' responses to a specific question regarding their opinion on the minimum level of experience required for health professionals to analyse portal images. We used grounded theory and a constant comparative method of data analysis to derive the main themes. Results: Forty-six radiation oncology facilities were represented in our survey, with 40 questionnaires being returned (87%). Thirty-seven radiation therapists answered our free-text question. Radiation therapists indicated three main themes which they felt were important in determining the minimum level of experience: 'gaining on-the-job experience', 'receiving training' and 'working as a team'. Conclusions: Radiation therapists indicated that competence in portal image review occurs via various learning mechanisms. Further research is warranted to determine perspectives of other health professionals, such as radiation oncologists, on portal image review becoming part of radiation therapists' extended role. Suitable training programs and steps for implementation should be developed to facilitate this endeavour

Discrete level schemes and their gamma radiation branching ratios (CENPL-DLS). Pt. 1

International Nuclear Information System (INIS)

Su Zongdi; Zhang Limin; Zhou Chunmei; Sun Zhengjun

1994-01-01

The DLS data file, which is a sub-library (version 1) of Chinese Evaluated Nuclear Parameter Library (CENPL), consists of data and information of discrete levels and gamma radiations. The data and information of this data file are translated from the Evaluated Nuclear Structure Data File (ENSDF). The transforming code from ENSDF to DLS was written. In the DLS data file, there are the data on discrete levels with determinate energy and their gamma radiations. At present, this file contains the data of 79456 levels and 100411 gammas for 1908 nuclides

Radiation exposure rate and liquid level measurement inside a high level liquid waste (HLLW) storage tank

International Nuclear Information System (INIS)

Sur, B.; Yue, S.; Thekkevarriam, A.

2007-01-01

An instrument based on an inexpensive, small silicon diode has been developed and used to measure, for the first time, the gamma radiation exposure rate profile inside a 6.4 mm diameter reentrant thermo-well tube, immersed in the highly radioactive liquid solution in an HLLW storage tank. The measurement agrees with previous calculations of exposure rate, and provides confirmation for safe and effective radiation work plans and material selection for investigations and remediation of the storage tank facility. The measured radiation exposure rate profile is also used to confirm that the position of tank internal structures have not changed because of aging and corrosion, and to obtain, within a few mm, the level of liquid inside the tank. (author)

Radiotherapy in primary cerebral lymphoma

International Nuclear Information System (INIS)

Legros, L.; Benezery, K.; Lagrange, J.L.

1999-01-01

Primary cerebral lymphoma is a rare disease with an unfavorable prognosis. Whole brain radiotherapy has been the standard treatment, but neither the optimal radiation fields nor optimal dose level of the regimen are as yet firmly establisheD. From this review of the literature, it seems that the whole brain must be treated, and a boost to the area of the primary site must be discussed. With regard to dose, the radiation dose-response relationship is not clearly proven. Yet, a minimum dose of 40 Gy is necessary, and the maximum dose is set at 50 Gy because of late neurological sequelae. Because of the poor prognosis of this disease and the risk of late sequelae, other avenues have been explored. Chemotherapy has been studied, seem to have a survival advantage and combinations of radiotherapy and chemotherapy, especially with high-dose methotrexate. Because primary cerebral lymphoma is an uncommon disease, randomized clinical trials that compare radiotherapy alone to chemotherapy plus radiotherapy may not be feasible. Finally, even if chemotherapy seems to have a survival advantage, the regimen of chemotherapy is still a matter of debate. (authors)

Comparison of primary radiation versus robotic surgery plus adjuvant radiation in high-risk prostate cancer: A single center experience

Directory of Open Access Journals (Sweden)

Prabhsimranjot Singh

2015-01-01

Full Text Available Objective: The objective of this study was to compare robotic-prostatectomy plus adjuvant radiation therapy (RPRAT versus primary RT for high-risk prostate cancer (HRPCa. Materials and Methods: A retrospective chart review was performed for the HRPCa patients treated in our institution between 2000 and 2010. One hundred and twenty-three patients with high-risk disease were identified. The Chi-square test and Fisher′s exact test were used to compare local control and distant failure rates between the two treatment modalities. For prostate-specific antigen comparisons between groups, Wilcoxon rank-sum test was used. Results: The median follow-up was 49 months (range: 3-138 months. Local control, biochemical recurrence rate, distant metastasis, toxicity, and disease-free survival were similar in the two groups. Conclusions: Primary RT is an excellent treatment option in patients with HRPCa, is equally effective and less expensive treatment compared with RPRAT. A prospective randomized study is required to guide treatment for patients with HRPCa.

Health effects of low-level radiation in shipyard workers. Final report: [Draft

Energy Technology Data Exchange (ETDEWEB)

Matanoski, G.M.

1991-06-01

The Nuclear Shipyard Workers Study (NSWS) was designed to determine whether there is an excess risk of leukemia or other cancers associated with exposure to low levels of gamma radiation. The study compares the mortality experience of shipyard workers who qualified to work in radiation areas to the mortality of similar workers who hold the same types of jobs but who are not authorized to work in radiation areas. The population consists of workers from six government and two private shipyards.

An EPID response calculation algorithm using spatial beam characteristics of primary, head scattered and MLC transmitted radiation

International Nuclear Information System (INIS)

Rosca, Florin; Zygmanski, Piotr

2008-01-01

We have developed an independent algorithm for the prediction of electronic portal imaging device (EPID) response. The algorithm uses a set of images [open beam, closed multileaf collimator (MLC), various fence and modified sweeping gap patterns] to separately characterize the primary and head-scatter contributions to EPID response. It also characterizes the relevant dosimetric properties of the MLC: Transmission, dosimetric gap, MLC scatter [P. Zygmansky et al., J. Appl. Clin. Med. Phys. 8(4) (2007)], inter-leaf leakage, and tongue and groove [F. Lorenz et al., Phys. Med. Biol. 52, 5985-5999 (2007)]. The primary radiation is modeled with a single Gaussian distribution defined at the target position, while the head-scatter radiation is modeled with a triple Gaussian distribution defined downstream of the target. The distances between the target and the head-scatter source, jaws, and MLC are model parameters. The scatter associated with the EPID is implicit in the model. Open beam images are predicted to within 1% of the maximum value across the image. Other MLC test patterns and intensity-modulated radiation therapy fluences are predicted to within 1.5% of the maximum value. The presented method was applied to the Varian aS500 EPID but is designed to work with any planar detector with sufficient spatial resolution

Linear devices in combined high-level radiation environments

International Nuclear Information System (INIS)

van Vonno, N.W.

1987-01-01

The design of precision analog integrated circuits for use in combined high-level radiation environments has traditionally been on a full-custom basis. The use of semicustom design methods has become prevalent in digital devices, with standard cell libraries and gate arrays readily available from multiple vendors. This paper addresses the application of semicustom design techniques to analog parts. In all cases the emphasis is on bipolar technology, since this provides an optimal combination of precision and radiation hardness. A mixed mode analog/digital (A/D) cell family for implementing semicustom designs is described, together with the fabrication process used. Specific processing and design methods are used to provide circuit hardness against neutron, total gamma dose, and transient gamma environments. Semicustom mixed analog/digital design is seen as an appropriate methodology for implementation of medium-performance mixed mode functions for radiation-hardened applications. This leads to trade-offs in process complexity and performance. Full custom design remains necessary for demanding applications such as high-speed A/D conversion and associated sample/hold functions. An A/D cell family optimized for hardness is described, together with the bipolar process used to implement it

Energy levels, lifetimes and radiative data of W LV

Science.gov (United States)

Ding, Xiao-bin; Sun, Rui; Koike, Fumihiro; Murakami, Izumi; Kato, Daiji; Sakaue, Hiroyuki A.; Nakamura, Nobuyuki; Dong, Chen-zhong

2018-01-01

Calculations of energy levels, radiative data and lifetimes are reported for tungsten Ca-like ion (W LV) by using multi-configuration Dirac-Fock (MCDF) method. The GRASP2K package is adopted to carry out a large-scale systematic computation with a restricted active space treatment; the Breit interaction and QED effects are included in subsequent relativistic configuration interaction calculations. The energies and lifetimes of the lowest 119 levels are listed; the main leading configuration of the levels is of the ground state configuration [Ne]3s23p63d2 and the first excited configuration [Ne]3s23p53d3. The wavelengths, radiative rates and oscillator strengths for relatively strong E1, E2, M1, and M2 transitions are listed. Comparisons with earlier experimental and theoretical values are made. The average relative deviations of energy levels from the NIST results and E1 transition wavelengths from the EBIT experimental results have turned to be only 0.20% and 0.13%, respectively. The other present results are in reasonable agreement with available data. These agreements confirm the reliability and accuracy of the current results. The present datasets may help us with the investigation of the electron-electron correlation effects in complex multi-electron highly charged heavy ions and of the diagnosis of tungsten impurity plasmas in fusion science.

Energy levels and radiative rates for transitions in Ti VI

International Nuclear Information System (INIS)

Aggarwal, K M; Keenan, F P; Msezane, A Z

2013-01-01

We report on calculations of energy levels, radiative rates, oscillator strengths and line strengths for transitions among the lowest 253 levels of the (1s 2 2s 2 2p 6 ) 3s 2 3p 5 , 3s3p 6 , 3s 2 3p 4 3d, 3s3p 5 3d, 3s 2 3p 3 3d 2 , 3s 2 3p 4 4s, 3s 2 3p 4 4p and 3s 2 3p 4 4d configurations of Ti VI. The general-purpose relativistic atomic structure package and flexible atomic code are adopted for the calculations. Radiative rates, oscillator strengths and line strengths are reported for all electric dipole (E1), magnetic dipole (M1), electric quadrupole (E2) and magnetic quadrupole (M2) transitions among the 253 levels, although calculations have been performed for a much larger number of levels. Comparisons are made with existing available results and the accuracy of the data is assessed. Additionally, lifetimes for all 253 levels are listed, although comparisons with other theoretical results are limited to only 88 levels. Our energy levels are estimated to be accurate to better than 1% (within 0.03 Ryd), whereas results for other parameters are probably accurate to better than 20%. A reassessment of the energy level data on the National Institute of Standards and Technology website for Ti VI is suggested. (paper)

[Risk factors and burnout levels in Primary Care nurses: A systematic review].

Science.gov (United States)

Gómez-Urquiza, Jose L; Monsalve-Reyes, Carolina S; San Luis-Costas, Concepción; Fernández-Castillo, Rafael; Aguayo-Estremera, Raimundo; Cañadas-de la Fuente, Guillermo A

2017-02-01

To determine the risk factors and levels of burnout in Primary Care nurses. A systematic review was performed. CINAHL, CUIDEN, LILACS, PubMed, ProQuest, ScienceDirect and Scopus databases were consulted. Search equations were 'burnout AND community health nursing' and 'burnout AND primary care nursing'. The search was performed in October 2015. The final sample was n=12 studies. Quantitative primary studies that used Maslach Burnout Inventory for burnout assessment in Primary Care nurses were included without restriction by publication date. The main variables were the mean and standard deviation of the three burnout dimensions, high, medium and low prevalence rates of each dimension, and socio-demographic, occupational and psychological variables that potentially influence burnout level. Studies show high prevalence rates, generally between 23% and 31%, of emotional exhaustion. The prevalence rates of high depersonalisation and low personal accomplishment show heterogeneity, varying between 8%-32% and 4%-92% of the sample, respectively. Studies show that older nurses with more seniority, anxiety and depression, among other variables, have higher burnout levels, while nurses with higher salary, high job satisfaction, organisational support, and good self-concept have less burnout. High emotional exhaustion is the main affected dimension of burnout in Primary Care nursing. There is heterogeneity in depersonalisation and personal accomplishment. Burnout must be prevented in these professionals, by increasing protective factors and monitoring its appearance in those with risk factors. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

Effect of surface treatments on radiation buildup in steam generators

International Nuclear Information System (INIS)

Asay, R.H.; Pick, M.E.; van Melsen, C.

1991-11-01

Test coupons of typical PWR materials of construction were prepared using a number of pretreatments to minimize radiation buildup. The coupons were then exposed to primary coolant at the Doel-2 PWR in Belgium. The exposure periods for the coupons ranged from one to three fuel cycles. After removal from the primary system, doserate and gamma spectroscopy measurements were made to determine the radioactivity levels on the coupons. Varying levels of success were achieved for the preconditioning techniques tested. Electropolishing alone provided some degree of resistance to radiation buildup on the treated surface and electropolishing plus passivation was shown to be even better. Radiation buildup resistance of the palladium-coated coupons was poor; radiation levels on these coupons were even higher than on the untreated reference coupons. The poor performance of the palladium-coated coupons was possibly due to the method used to apply the coating. In contrast to palladium coating, very encouraging results were achieved with chromium plating plus passivation. Preliminary results show that this technique can inhibit activity deposition by as much as a factor of ten. 4 refs., 64 figs., 26 tabs

Effects of chronic low level radiation in the population residing in the high level natural radiation area in Kerala, India: employing heritable DNA mutation studies.

Science.gov (United States)

Ahmad, Shazia; Koya, P K M; Seshadri, M

2013-03-18

To study the effect of chronic low level radiation, 4040 meiosis were screened at eight microsatellite and five minisatellite (2485 and 1555 meiosis respectively) marker loci in people residing in high and normal level natural radiation areas of Kerala. Variants in the repeat length of allele were considered as mutants. Mutation rates (expressed as the number of mutations observed in the total number of meiosis) were 6.4×10(-3) (16/2485) and 2.6×10(-3) (4/1555) at microsatellite and minisatellite respectively. The germline microsatellite mutation frequency of father was 1.78 times higher at 7.52×10(-3) (8/1064) compared to 4.22×10(-3) (6/1421) of mother (P=0.292, Fisher's Exact two-sided test). The paternal and maternal mutation rates at minisatellite loci were more or less similar at 2.78×10(-3) (2/719) and 2.39×10(-3) (2/836), respectively (P=1.0, Fisher's Exact two-sided test). Higher but statistically non-significant microsatellite mutation frequency was observed in HLNRA compared to NLNRA (7.25×10(-3) vs 3.64×10(-3); P=0.547). The apparent increase in the mutation rate of microsatellite loci with the increase in radiation dose was also not statistically significant. All the four minisatellite mutation observed were from HLNRA (1198 meiosis) and no mutation was observed among 357 meiosis screened from NLNRA families. All the markers used in the present study were in the non-coding region and hence mutations in these regions may not cause adverse health effects, but the study is important in understanding the effect of chronic low level radiation. Copyright © 2012 Elsevier B.V. All rights reserved.

Radiation exposure from incorporated isotopes

Energy Technology Data Exchange (ETDEWEB)

Beleznay, F [Hungarian Academy of Sciences, Budapest. Central Research Inst. for Physics

1985-01-01

Recommendations for the limitation of the burden of the human body from radiation exposure were developed to avoid direct radiation health damage such that the occurrence of stochastic damage can be held below a resonable risk level. The recommendations, published under ICRP 26 and ICRP 30, contain several guidelines and concepts which are discussed here. They include the primary internal dose exposure limits, secondary and implied limits for the monitoring of internal radiation exposure (Annual Limit of Intake, Derived Air Concentrations). Methods are presented for inspection and monitoring of internal exposure in medical laboratories, inspection of incorporation of sup(131)I and sup(99m)Tc.

Prediction of soot and thermal radiation in a model gas turbine combustor burning kerosene fuel spray at different swirl levels

Science.gov (United States)

Ghose, Prakash; Patra, Jitendra; Datta, Amitava; Mukhopadhyay, Achintya

2016-05-01

Combustion of kerosene fuel spray has been numerically simulated in a laboratory scale combustor geometry to predict soot and the effects of thermal radiation at different swirl levels of primary air flow. The two-phase motion in the combustor is simulated using an Eulerian-Lagragian formulation considering the stochastic separated flow model. The Favre-averaged governing equations are solved for the gas phase with the turbulent quantities simulated by realisable k-ɛ model. The injection of the fuel is considered through a pressure swirl atomiser and the combustion is simulated by a laminar flamelet model with detailed kinetics of kerosene combustion. Soot formation in the flame is predicted using an empirical model with the model parameters adjusted for kerosene fuel. Contributions of gas phase and soot towards thermal radiation have been considered to predict the incident heat flux on the combustor wall and fuel injector. Swirl in the primary flow significantly influences the flow and flame structures in the combustor. The stronger recirculation at high swirl draws more air into the flame region, reduces the flame length and peak flame temperature and also brings the soot laden zone closer to the inlet plane. As a result, the radiative heat flux on the peripheral wall decreases at high swirl and also shifts closer to the inlet plane. However, increased swirl increases the combustor wall temperature due to radial spreading of the flame. The high incident radiative heat flux and the high surface temperature make the fuel injector a critical item in the combustor. The injector peak temperature increases with the increase in swirl flow mainly because the flame is located closer to the inlet plane. On the other hand, a more uniform temperature distribution in the exhaust gas can be attained at the combustor exit at high swirl condition.

Trade Study of System Level Ranked Radiation Protection Concepts for Deep Space Exploration

Science.gov (United States)

Cerro, Jeffrey A

2013-01-01

A strategic focus area for NASA is to pursue the development of technologies which support exploration in space beyond the current inhabited region of low earth orbit. An unresolved issue for crewed deep space exploration involves limiting crew radiation exposure to below acceptable levels, considering both solar particle events and galactic cosmic ray contributions to dosage. Galactic cosmic ray mitigation is not addressed in this paper, but by addressing credible, easily implemented, and mass efficient solutions for the possibility of solar particle events, additional margin is provided that can be used for cosmic ray dose accumulation. As a result, NASA s Advanced Engineering Systems project office initiated this Radiation Storm Shelter design activity. This paper reports on the first year results of an expected 3 year Storm Shelter study effort which will mature concepts and operational scenarios that protect exploration astronauts from solar particle radiation events. Large trade space definition, candidate concept ranking, and a planned demonstration comprised the majority of FY12 activities. A system key performance parameter is minimization of the required increase in mass needed to provide a safe environment. Total system mass along with operational assessments and other defined protection system metrics provide the guiding metrics to proceed with concept developments. After a downselect to four primary methods, the concepts were analyzed for dosage severity and the amount of shielding mass necessary to bring dosage to acceptable values. Besides analytical assessments, subscale models of several concepts and one full scale concept demonstrator were created. FY12 work terminated with a plan to demonstrate test articles of two selected approaches. The process of arriving at these selections and their current envisioned implementation are presented in this paper.

A guide to radiation and radioactivity levels near high energy particle accelerators

International Nuclear Information System (INIS)

Sullivan, A.H.

1992-01-01

An estimate of likely radiation and radioactivity levels is needed at the design stage of an accelerator for deciding the radiation safety features to be incorporated in the infrastructure of the machine and for predicting where radiation damage possibilities will have to be taken into account. Both these aspects can have a significant influence on the machine layout and cost. Failure to make a reasonable assessment at the right time may have far reaching consequences for future costs. The purpose of this guide is to bring together basic data and methods that have been found useful in assessing radiation situations around accelerators and to provide a practical means of arriving at the radiation and induced radioactivity levels that could occur under a wide variety of circumstances. An attempt is made to present the information in a direct and unambiguous way with sufficient confidence that the necessity for large safety factors is avoided. In many cases assumptions and simplifications have been made and reliance placed on extrapolating from experimental data into regions where the basic physics is too complicated to make meaningful absolute calculations. Wherever possible such extrapolations have been tied to real or otherwise acceptable data originating from independent sources. (Author)

Investigation of environmental natural penetrating radiation level in Beijing

International Nuclear Information System (INIS)

Wu Zengxin; Zhang Wenying; Zheng Rukuan; Wei Shujun; Ding Huiqiu

1992-01-01

The authors report the methods and results of investigation of environmental natural penetrating radiation level in Beijing. There were 83 measurement points selected, which were located at the vertexes of 1 x 1 km square meshes and uniformly distributed over the urban district. 173 net grid measuring points selected with grid spacing of 10 x 10 km and uniformly distributed over the suburban district. Another 131 more densely distributed points were added over some special areas. The results show that: (1) The point-weighted, area-weighted and population-weighted average value of natural γ radiation dose rate over field is 56.2, 56.4 and 50.1 nGy · h -1 respectively. The γ radiation dose rate is higher in west and north area than in southeast area. (2) The point-weighted average value of natural γ radiation dose rate over roads was 49.3 nGy · h -1 . (3) The point weighted and population-weighted average value of natural γ radiation dose inside buildings was 83.5 and 77.1 nGy · h -1 respectively. (4) The weighted average of air absorbed dose rate from the ionizing components of cosmic rays (except for neutron) over point number and population was respectively 29.0 and 27.5 nGy · h -1 indoors, and 32.3 and 30.8 nGy · h -1 outdoors. (5) The point and population-weighted means of natural penetrating radiation dose rate (the contribution from neutron is not included) are 112.8 and 104.5 nGy · h -1 indoors, respectively; 88.7 and 81.3 nGy · h -1 outdoors, respectively. (6) The annual effective dose equivalent per capital people natural γ radiation, cosmic ray and natural penetrating radiation was 0.43, 0.25 and 0.68 mSv respectively, and the annual collective effective dose equivalent was 4.0, 2.3 and 6.3 x 10 3 man · Sv, respectively

Radiation induced deep level defects in bipolar junction transistors under various bias conditions

International Nuclear Information System (INIS)

Liu, Chaoming; Yang, Jianqun; Li, Xingji; Ma, Guoliang; Xiao, Liyi; Bollmann, Joachim

2015-01-01

Bipolar junction transistor (BJT) is sensitive to ionization and displacement radiation effects in space. In this paper, 35 MeV Si ions were used as irradiation source to research the radiation damage on NPN and PNP bipolar transistors. The changing of electrical parameters of transistors was in situ measured with increasing irradiation fluence of 35 MeV Si ions. Using deep level transient spectroscopy (DLTS), defects in the bipolar junction transistors under various bias conditions are measured after irradiation. Based on the in situ electrical measurement and DLTS spectra, it is clearly that the bias conditions can affect the concentration of deep level defects, and the radiation damage induced by heavy ions.

Carcinogenesis and low-level ionizing radiation with special reference to lung cancer and exposure to radon daughters

Energy Technology Data Exchange (ETDEWEB)

Fabrikant, J.I.

1982-04-01

Of the important health effects of ionizing radiation, three important late effects - carcinogenesis, teratogenesis and mutagenesis are of greatest concern. This is because any exposure, even at low levels, carries some risk of such deleterious effects. As the dose of radiation increases above very low levels, the risk of health effects increases. Cancer-induction is the most important late somatic effect of low-dose ionizing radiation. Solid cancers, rather than leukemia, are principal late effects in exposed individuals. Tissues vary greatly in their susceptibility to radiation carcinogenesis. The most frequently occurring radiation-induced cancers in man include, in decreasing order of susceptibility: the female breast, the thyroid gland, the blood-forming tissues, the lung, certain organs of the gastrointestinal tract, and the bones. A number of biological and physical factors affect the cancer risk, such as age, sex, life-style, LET, and RBE. Despite uncertainty about low-level radiation risks, regulatory and advisory bodies must set standards for exposure, and individuals need information to be able to make informed judgments for themselves. From the point of view of the policy maker, the overriding concern is the fact that small doses of radiation can cause people to have more cancers than would otherwise be expected. While concern for all radiation effects exists, our human experience is limited to cancer-induction in exposed populations. This discussion is limited to cancer risk estimation and decision-making in relation to the health effects on populations of exposure to low levels of ionizing radiation. Here, low-level radiation will refer to yearly whole-body doses up to 5 rems or 0.05 Sv, or to cumulative doses up to 50 rems or 0.5 Sv from low-LET radiation and from high-LET radiation. (ERB)

Carcinogenesis and low-level ionizing radiation with special reference to lung cancer and exposure to radon daughters

International Nuclear Information System (INIS)

Fabrikant, J.I.

1982-04-01

Of the important health effects of ionizing radiation, three important late effects - carcinogenesis, teratogenesis and mutagenesis are of greatest concern. This is because any exposure, even at low levels, carries some risk of such deleterious effects. As the dose of radiation increases above very low levels, the risk of health effects increases. Cancer-induction is the most important late somatic effect of low-dose ionizing radiation. Solid cancers, rather than leukemia, are principal late effects in exposed individuals. Tissues vary greatly in their susceptibility to radiation carcinogenesis. The most frequently occurring radiation-induced cancers in man include, in decreasing order of susceptibility: the female breast, the thyroid gland, the blood-forming tissues, the lung, certain organs of the gastrointestinal tract, and the bones. A number of biological and physical factors affect the cancer risk, such as age, sex, life-style, LET, and RBE. Despite uncertainty about low-level radiation risks, regulatory and advisory bodies must set standards for exposure, and individuals need information to be able to make informed judgments for themselves. From the point of view of the policy maker, the overriding concern is the fact that small doses of radiation can cause people to have more cancers than would otherwise be expected. While concern for all radiation effects exists, our human experience is limited to cancer-induction in exposed populations. This discussion is limited to cancer risk estimation and decision-making in relation to the health effects on populations of exposure to low levels of ionizing radiation. Here, low-level radiation will refer to yearly whole-body doses up to 5 rems or 0.05 Sv, or to cumulative doses up to 50 rems or 0.5 Sv from low-LET radiation and from high-LET radiation

Epidemiological surveys on the effects of low-level radiation dose: a comparative assessment. Vol. A: pre-conception irradiation effects. Vol. E (DRAFT A): group collation tables

Energy Technology Data Exchange (ETDEWEB)

Rose, K.S.B.

1988-01-01

In this report, the health effects of low-level doses of radiation are considered by reference to published epidemiological surveys. The work was carried out with three objectives in mind: 1. to provide a comprehensive and critical review of the subject; 2. to seek consistent indications of particular health effects by collating results and comparing with those from surveys at moderate-level doses; 3. to provide an authoritative view on the epidemiology of low-level radiation-induced health effects. Vol E (DRAFT A) is appended and contains group collation tables. Epidemiological surveys can be conveniently divided into four classes (A, B, C, D) according to the phase of life when irradiation occurs or the effect is diagnosed. The first of the classes (A) is addressed here; this class is concerned with possible effects arising from radiation received by a parent before conception. Possible effects of preconception irradiation were identified under four broad groupings. These are Down's syndrome, ''Indicators of Reproductive Damage'' (mainly Primary Sterility, Congenital Abnormalities, Sex Ratio, Fetal Mortality, Infant Mortality), Childhood Malignancies, and Chromosomal Changes in Abortuses. Information about each survey, and comparisons with results from moderate-level dose surveys, are contained in synopses that are set out in the Appendix.

Investigation of the electromagnetic radiation field level in the vicinity of Damascus international airport

International Nuclear Information System (INIS)

Abukassem, I.

2011-07-01

The aim of this work is to estimate the electromagnetic radiation exposure of Damascus international airport workers.Different kinds of electromagnetic wave sources exist in the vicinity of the airport, for example, mobile phone base stations. It was found that the exposure level in all studied points (offices, halls, traffic control tour, etc) is lower than the international restriction levels. Few recommendations were given for some work situation or places where the measured electromagnetic radiation levels were relatively high.(author)

Primary health services at district level in South Africa: a critique of the primary health care approach

Directory of Open Access Journals (Sweden)

Dookie Sunitha

2012-07-01

Full Text Available Abstract Background The rhetoric of primary health care philosophy in the district health system is widely cited as a fundamental component of the health transformation process in post-apartheid South Africa. Despite South Africa’s progress and attempts at implementing primary health care, various factors still limit its success. Discussion Inconsistencies and poor understanding of primary care and primary health care raises unrealistic expectations in service delivery and health outcomes, and blame is apportioned when expectations are not met. It is important for all health practitioners to consider the contextual influences on health and ill-health and to recognise the role of the underlying determinants of ill-health, namely, social, economic and environmental influences. The primary health care approach provides a strong framework for this delivery but it is not widely applied. There is a need for renewed political and policy commitments toward quality primary health care delivery, re-orientation of health care workers, integration of primary health care activities into other community-based development, improved management skills and effective coordination at all levels of the health system. There should also be optimal capacity building, and skills development in problem-solving, communication, networking and community participation. Summary A well-functioning district health system is required for the re-engineering of primary health care. This strategy requires a strong leadership, a strengthening of the current district heath system and a greater emphasis on health promotion, prevention, and community participation and empowerment.

A possible methodological approach to setting up control level of radiation factors

International Nuclear Information System (INIS)

Devyatajkin, E.V.; Abramov, Yu.V.

1986-01-01

The mathematical formalization of the concept of control levels (CL) which enables one to obtain CL numerical values of controllable parameters required for rapid control purposes is described. The initial data for the assessment of environmental radioactivity are the controllable parameter values that is practical characteristic of controllable radiation factor showing technically measurable or calculation value. The controllable parameters can be divided into two classes depending on the degree of radiation effect on a man: possessing additivity properties (dosimetric class) and non-possessing (radiation class, which comprises the results of control of medium alteration dynamics, equipment operation safety, completeness of protection measures performance). The CL calculation formulas with account for requirements of radiation safety standards (RSS-76) are presented

Critical review of the Hanford worker studies: cancer risk and low-level radiation

International Nuclear Information System (INIS)

Savitz, D.A.

1983-01-01

Current estimates of cancer risks attributable to low-level radiation exposure are extrapolated from effects observed at higher doses. The inherent uncertainties in this approach make direct study of low-dose effects in human populations of great significance. Employees of the Hanford works in Richland, Washington constitute a large group of workers exposed to low-level radiation. The cancer mortality patterns in relation to radiation dose have been discussed by numerous investigators beginning with Mancuso, Stewart, and Kneale in 1977 and continuing to the present. These studies and their published critiques are summarized, with an effort to account for discrepant results by careful review of the analytic methods. Detailed consideration is given to exposure definition, classification of health outcomes, latency, the statistical methods employed, and selection biases. From this, it is concluded that (a) total cancers are unrelated to radiation exposure among these workers; (b) multiple myeloma and pancreatic cancer show a positive association with radiation dose based upon a few highly exposed cases; and (c) the relationship of radiosensitive cancers in the aggregate to radiation exposure is unresolved. Further study of the temporal course of exposure and latency in a classical cohort analysis of radiosensitive cancers might be informative, with special attention to the possibility of selection for jobs within the cohort

Main radiation protection actions for medical personnel as primary responders front of an event with radiological dispersive device

International Nuclear Information System (INIS)

Duque, Hildanielle Ramos

2015-01-01

After the terrorist attack in New York, USA, in 2001, there was a worldwide concern about possible attacks using radioactive material in conventional detonators, called as Radiological Dispersal Device (RDD) or 'dirty bomb'. Several studies have been and are being made to form a global knowledge about this type of event. As until now, fortunately, there has not been an event with RDD, the Goiania Radiological Accident in Brazil, 1987, is used as a reference for decision-making. Several teams with technical experts should act in an event with RDD, but the medical staffs who respond quickly to the event must be properly protected from the harmful effects of radiation. Based on the radiological protection experts performance during the Goiania accident and the knowledge from lessons learned of many radiological accidents worldwide, this work presents an adaptation of the radiation protection actions for an event with RDD that helps a medical team as primary responders. The following aspects are presented: the problem of radioactive contamination from the explosion of the device in underground environment, the actions of the first responders and evaluation of health radiation effects. This work was based on specialized articles and papers about radiological accidents and RDD; as well as personal communication and academic information of the Institute of Radiation Protection and Dosimetry. The radiation protection actions, adapted to a terrorist attack event with RDD, have as a scenario a subway station in the capital. The main results are: the use of the basic radiation protection principle of time because there is no condition to take care of a patient keeping distance or using a shielding; the use of full appropriate protection cloths for contaminating materials ensuring the physical safety of professionals, and the medical team monitoring at the end of a medical procedure, checking for surface contamination. The main conclusion is that all medical actions

Reproductive Status at First Diagnosis Influences Risk of Radiation-Induced Second Primary Contralateral Breast Cancer in the WECARE Study

Energy Technology Data Exchange (ETDEWEB)

Brooks, Jennifer D., E-mail: brooksj@mskcc.org [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Boice, John D. [International Epidemiology Institute, Rockville, MD and Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center, Vanderbilt School of Medicine, Nashville, TN (United States); Stovall, Marilyn [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Reiner, Anne S. [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Bernstein, Leslie [Division of Cancer Etiology, Department of Population Sciences, Beckman Research Institute and City of Hope Comprehensive Cancer Center, Duarte, CA (United States); John, Esther M. [Cancer Prevention Institute of California, Fremont, CA, and Stanford University School of Medicine and Stanford Cancer Institute, Stanford, CA (United States); Lynch, Charles F. [Department of Epidemiology, University of Iowa, Iowa City, IA (United States); Mellemkjaer, Lene [Institute of Cancer Epidemiology, Danish Cancer Society, Copenhagen (Denmark); Knight, Julia A. [Dalla Lana School of Public Health, University of Toronto and Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario (Canada); Thomas, Duncan C.; Haile, Robert W. [Department of Preventive Medicine, University of Southern California, Los Angeles, CA (United States); Smith, Susan A. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Capanu, Marinela; Bernstein, Jonine L. [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Shore, Roy E. [Department of Environmental Medicine, New York University, New York, NY (United States); Radiation Effects Research Foundation, Hiroshima (Japan)

2012-11-15

Purpose: Our study examined whether reproductive and hormonal factors before, at the time of, or after radiation treatment for a first primary breast cancer modify the risk of radiation-induced second primary breast cancer. Methods and Materials: The Women's Environmental, Cancer and Radiation Epidemiology (WECARE) Study is a multicenter, population-based study of 708 women (cases) with asynchronous contralateral breast cancer (CBC) and 1399 women (controls) with unilateral breast cancer. Radiotherapy (RT) records, coupled with anthropomorphic phantom simulations, were used to estimate quadrant-specific radiation dose to the contralateral breast for each patient. Rate ratios (RR) and 95% confidence intervals (CI) were computed to assess the relationship between reproductive factors and risk of CBC. Results: Women who were nulliparous at diagnosis and exposed to {>=}1 Gy to the contralateral breast had a greater risk for CBC than did matched unexposed nulliparous women (RR = 2.2; 95% CI, 1.2-4.0). No increased risk was seen in RT-exposed parous women (RR = 1.1; 95% CI, 0.8-1.4). Women treated with RT who later became pregnant (8 cases and 9 controls) had a greater risk for CBC (RR = 6.0; 95% CI, 1.3-28.4) than unexposed women (4 cases and 7 controls) who also became pregnant. The association of radiation with risk of CBC did not vary by number of pregnancies, history of breastfeeding, or menopausal status at the time of first breast cancer diagnosis. Conclusion: Nulliparous women treated with RT were at an increased risk for CBC. Although based on small numbers, women who become pregnant after first diagnosis also seem to be at an increased risk for radiation-induced CBC.

Approaches to assign security levels for radioactive substances and radiation sources

International Nuclear Information System (INIS)

Ivanov, M.V.; Petrovskij, N.P.; Pinchuk, G.N.; Telkov, S.N.; Kuzin, V.V.

2011-01-01

The article contains analyzed provisions on categorization of radioactive substances and radiation sources according to the extent of their potential danger. Above provisions are used in the IAEA documents and in Russian regulatory documents for differentiation of regulatory requirements to physical security. It is demonstrated that with the account of possible threats of violators, rules of physical protection of radiation sources and radioactive substances should be amended as regards the approaches to assign their categories and security levels [ru

Effects of low-level radiation on biologic systems: a literature review

International Nuclear Information System (INIS)

Best, T.L.; Hoditschek, B.

1980-12-01

This review presents an organized survey of scientific literature dealing with the biologic effects of low-level radiation. It includes brief discussions of topics of particular interest, a listing of useful review articles, an extensive bibliography, and listings of sources that can be used to update this document in the future. The topics discussed include experimental studies, the linear hypothesis, medical effects, occupational effects, effects of exposure to naturally occurring radiation, consumer products, and laws and regulations

Investigation of environmental natural penetrating radiation level in Anhui province

International Nuclear Information System (INIS)

Zhu Jingqiu; Chen Shuping; Jiang Shan; Zhu Xingsheng; Huang Jiangbin; Wu Chuanyong; Wang Weining

1992-01-01

The methods and results of the investigation on natural penetrating radiation level in Anhui Province in 1987 are presented. The results show that: (1) The point-weighted, area-weighted and population-weighted average value of natural γ radiation dose rate for field is 5.67, 5.62 and 5.55 x 10 -8 Gy· -1 , respectively; (2) The point-weighted average value of natural γ radiation dose rate for road is 5.38 x 10 -8 Gy·h -1 ; (3) The point-weighted and population-weighted average value of natural γ radiation dose rate inside buildings is 9.59 and 9.36 x 10 -8 Gy·h -1 , respectively; (4) The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 2.64 and 2.62 x 10 -8 ·h -1 , and outside buildings is 2.95 and 2.94 x 10 -8 ·h -1 , respectively; (5) The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside buildings is 12.23 and 11.99 x 10 -8 Gy·h -1 , outside buildings is 8.62 and 8.49 x 10 -8 ·h -1 , respectively; (6) The annual effective dose equivalent from natural γ radiation, cosmic ray and natural penetrating radiation is 0.51, 0.24, and 0.75 mSv, respectively; and correspondingly, the annual collective effective dose equivalent is 2.5, 1.2 and 3.7 x 10 4 man·Sv, respectively

Study on radioactive corrosion products behaviour in primary circuits of JOYO

International Nuclear Information System (INIS)

Iizawa, Katsuyuki; Suzuki, Soju; Tamura, Masaaki; Seki, Seiichi; Hikichi, Takayoshi

1987-01-01

Radioactive CP deposition and distribution, and the resulting radiation fields along the JOYO primary circuit piping have been measured. The measurement results have been compared with calculations for estimating radioactive CP behaviour and the resulting radiation fields in an LMFBR primary circuit using a computer code which is named PSYCHE. The deposited radioactivity of CPs calculated by using PSYCHE agreed well with the measured results within a factor of 0.5-2. The gamma dose rate distribution calculated from the PSYCHE results reproduced measured values within a factor of 0.6-2 over the piping system, using the JOANDARC modification of the QAD-CG code. Using these verified codes, a prediction of radiation levels for future plant operation, and an evaluation of methods for the reduction of radioactive CPs have been conducted. (orig./DG)

Reconstitution of active telomerase in primary human foreskin fibroblasts : effects on proliferative characteristics and response to ionizing radiation

NARCIS (Netherlands)

Kampinga, H.H.; Waarde-Verhagen, M.A.W.H. van; Assen-Bolt, A.J. van; Rodemann, H.P.; Prowse, K.R.; Linskens, M.H.K.

2004-01-01

Purpose: Telomere shortening has been proposed to trigger senescence, and since most primary cells do not express active telomerase, reactivation of telomerase activity was proposed as a safe and non-transforming way of immortalizing cells. However, to study radiation responses, it is as yet unclear

Techniques for detecting and determining risks from low-level radiation

International Nuclear Information System (INIS)

Boice, J.D.

1980-01-01

Epidemiology is the study of disease in man. In evaluating radiation hazards, analytic studies have utilized the cohort type of investigation (where persons exposed and not exposed to radiation are followed forward in time for determination of disease experience) or case-control approaches (where persons with and without a specific disease are evaluated for previous exposure to radiation). Most radiation studies have evaluated cohorts (e.g., radiologists), although important case-control studies have been conducted (e.g., childhood leukemia as related to prenatal x ray). At its best, epidemiology is capable fo evaluating relative risks (RR) on the order of 1.4 (i.e., a 40% relative excess). However, the RRs of interest following low doses of radiation (1 rad) are on the order of 1.02-1.002. Thus, not much should be anticipated from direct observations at 1 rad, and indirect approaches must be taken to estimate low-dose effects. Such indirect approaches include evaluating 1) populations exposed to a range of doses, both low and high, where interpolation models can be reasonably applied to estimate low-dose effects; and 2) populations exposed to fractionated doses over a long period of time where the resulting dose-effect relationship theoretically should be linear and the estimation of low-level health effects facilitated

Radiation-Related New Primary Solid Cancers in the Childhood Cancer Survivor Study: Comparative Radiation Dose Response and Modification of Treatment Effects

International Nuclear Information System (INIS)

Inskip, Peter D.; Sigurdson, Alice J.; Veiga, Lene; Bhatti, Parveen; Ronckers, Cécile; Rajaraman, Preetha; Boukheris, Houda; Stovall, Marilyn; Smith, Susan; Hammond, Sue; Henderson, Tara O.

2016-01-01

Objectives: The majority of childhood cancer patients now achieve long-term survival, but the treatments that cured their malignancy often put them at risk of adverse health outcomes years later. New cancers are among the most serious of these late effects. The aims of this review are to compare and contrast radiation dose–response relationships for new solid cancers in a large cohort of childhood cancer survivors and to discuss interactions among treatment and host factors. Methods: This review is based on previously published site-specific analyses for subsequent primary cancers of the brain, breast, thyroid gland, bone and soft tissue, salivary glands, and skin among 12,268 5-year childhood cancer survivors in the Childhood Cancer Survivor Study. Analyses included tumor site–specific, individual radiation dose reconstruction based on radiation therapy records. Radiation-related second cancer risks were estimated using conditional logistic or Poisson regression models for excess relative risk (ERR). Results: Linear dose–response relationships over a wide range of radiation dose (0-50 Gy) were seen for all cancer sites except the thyroid gland. The steepest slopes occurred for sarcoma, meningioma, and nonmelanoma skin cancer (ERR/Gy > 1.00), with glioma and cancers of the breast and salivary glands forming a second group (ERR/Gy = 0.27-0.36). The relative risk for thyroid cancer increased up to 15-20 Gy and then decreased with increasing dose. The risk of thyroid cancer also was positively associated with chemotherapy, but the chemotherapy effect was not seen among those who also received very high doses of radiation to the thyroid. The excess risk of radiation-related breast cancer was sharply reduced among women who received 5 Gy or more to the ovaries. Conclusions: The results suggest that the effect of high-dose irradiation is consistent with a linear dose–response for most organs, but they also reveal important organ-specific and host

Radiation-Related New Primary Solid Cancers in the Childhood Cancer Survivor Study: Comparative Radiation Dose Response and Modification of Treatment Effects

Energy Technology Data Exchange (ETDEWEB)

Inskip, Peter D., E-mail: inskippeter@gmail.com [Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Sigurdson, Alice J.; Veiga, Lene [Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Bhatti, Parveen [Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington (United States); Ronckers, Cécile [Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Department of Pediatric Oncology, Emma Children' s Hospital/Academic Medical Center, Amsterdam (Netherlands); Rajaraman, Preetha [Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Boukheris, Houda [Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); The University of Oran School of Medicine (Algeria); Stovall, Marilyn; Smith, Susan [Department of Radiation Physics, The University of Texas M.D. Anderson Cancer Center, Houston, Texas (United States); Hammond, Sue [Department of Laboratory Medicine and Pathology, Children' s Hospital and Ohio State University College of Medicine, Columbus, Ohio (United States); Henderson, Tara O. [University of Chicago Department of Pediatrics, Section of Hematology, Oncology and Stem Cell Transplantation, Chicago, Illinois (United States); and others

2016-03-15

Objectives: The majority of childhood cancer patients now achieve long-term survival, but the treatments that cured their malignancy often put them at risk of adverse health outcomes years later. New cancers are among the most serious of these late effects. The aims of this review are to compare and contrast radiation dose–response relationships for new solid cancers in a large cohort of childhood cancer survivors and to discuss interactions among treatment and host factors. Methods: This review is based on previously published site-specific analyses for subsequent primary cancers of the brain, breast, thyroid gland, bone and soft tissue, salivary glands, and skin among 12,268 5-year childhood cancer survivors in the Childhood Cancer Survivor Study. Analyses included tumor site–specific, individual radiation dose reconstruction based on radiation therapy records. Radiation-related second cancer risks were estimated using conditional logistic or Poisson regression models for excess relative risk (ERR). Results: Linear dose–response relationships over a wide range of radiation dose (0-50 Gy) were seen for all cancer sites except the thyroid gland. The steepest slopes occurred for sarcoma, meningioma, and nonmelanoma skin cancer (ERR/Gy > 1.00), with glioma and cancers of the breast and salivary glands forming a second group (ERR/Gy = 0.27-0.36). The relative risk for thyroid cancer increased up to 15-20 Gy and then decreased with increasing dose. The risk of thyroid cancer also was positively associated with chemotherapy, but the chemotherapy effect was not seen among those who also received very high doses of radiation to the thyroid. The excess risk of radiation-related breast cancer was sharply reduced among women who received 5 Gy or more to the ovaries. Conclusions: The results suggest that the effect of high-dose irradiation is consistent with a linear dose–response for most organs, but they also reveal important organ-specific and host

The correlation between osteopontin level and radiation response of malignant gliomas at Cipto Mangunkusumo Hospital

Directory of Open Access Journals (Sweden)

Isnaniah Hasan

2016-12-01

Full Text Available Osteopontin is an endogenous molecular marker for tumor hypoxia, and hypoxia is one of the factors that determine the aggressiveness of the disease. The purpose of this study is to determine the correlation between osteopontin levels and radiation response in malignant glioma. A retrospective cohort study was conducted on 15 malignant glioma patients who underwent radiation therapy from July 2004 to May 2015 at the RSUPN Dr. Cipto Mangunkusumo Hospital. Osteopontin levels were measured from paraffin-embedded tissue using a commercial ELISA kit. Tumor volume was calculated using computed tomography (CT scan and magnetic resonance imaging (MRI images, based on three-dimensional volume measurements. Tumor response was evaluated by comparing pre- and post-radiation tumor volumes using CT scan and MRI images. The mean osteopontin level was 0.49 ± 0.45 ng/mL and the mean percentage change in tumor volume was 8.59 ± 54.22%, with a 60% enlargement in tumor volume. A progressive disease was found in 26.7% of patients. There was a weak but insignificant negative correlation (r = -0.39, p = 0.146 between the level of osteopontin and radiation response. In contrast, there was a strong but insignificant positive correlation (r = +0.68, p = 0.219 between the level of osteopontin and radiation response in the patient group that used the chemosensitizer temozolamide.

Radiation-induced taste aversion: effects of radiation exposure level and the exposure-taste interval

International Nuclear Information System (INIS)

Spector, A.C.; Smith, J.C.; Hollander, G.R.

1986-01-01

Radiation-induced taste aversion has been suggested to possibly play a role in the dietary difficulties observed in some radiotherapy patients. In rats, these aversions can still be formed even when the radiation exposure precedes the taste experience by several hours. This study was conducted to examine whether increasing the radiation exposure level could extend the range of the exposure-taste interval that would still support the formation of a taste aversion. Separate groups of rats received either a 100 or 300 R gamma-ray exposure followed 1, 3, 6, or 24 h later by a 10-min saccharin (0.1% w/v) presentation. A control group received a sham exposure followed 1 h later by a 10-min saccharin presentation. Twenty-four hours following the saccharin presentation all rats received a series of twelve 23-h two-bottle preference tests between saccharin and water. The results indicated that the duration of the exposure-taste interval plays an increasingly more important role in determining the initial extent of the aversion as the dose decreases. The course of recovery from taste aversion seems more affected by dose than by the temporal parameters of the conditioning trial

Behaviour of radiation fields in the Spanish PWR by the changes in coolant chemistry and primary system materials

International Nuclear Information System (INIS)

Llovet, R.; Fernandez Lillo, E.

1995-01-01

The Spanish PWR Owners Group established a program to evaluate the behavior of ex-core radiation fields and discriminate the effects of changes in coolant chemistry and primary system materials. Data from Vandellos, Asco, Almaraz and Trillo NPPs were analyzed Vandellos 2 was chosen as the lead plant and its data were thoroughly studied. The dose-rates evolution could be explained at each plant as a consequence of this sucessful program.Actions derived from the developed knowledge on this field have produced the stabilization or even reduction of radiation fields at these plants

Prognostic Impact of Radiation Therapy to the Primary Tumor in Patients With Non-small Cell Lung Cancer and Oligometastasis at Diagnosis

Energy Technology Data Exchange (ETDEWEB)

Lopez Guerra, Jose Luis [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Radiation Oncology, Instituto Madrileno de Oncologia/Grupo IMO, Madrid (Spain); Gomez, Daniel, E-mail: dgomez@mdanderson.org [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Zhuang, Yan; Hong, David S. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Heymach, John V. [Department of Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Swisher, Stephen G. [Department of Thoracic Surgery, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Lin, Steven H.; Komaki, Ritsuko; Cox, James D.; Liao Zhongxing [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

2012-09-01

Purpose: We investigated prognostic factors associated with survival in patients with non-small cell lung cancer (NSCLC) and oligometastatic disease at diagnosis, particularly the influence of local treatment to the primary site on prognosis. Methods and Materials: From January 2000 through June 2011, 78 consecutive patients with oligometastatic NSCLC (<5 metastases) at diagnosis underwent definitive chemoradiation therapy ({>=}45 Gy) to the primary site. Forty-four of these patients also received definitive local treatment for the oligometastases. Survival outcomes were estimated using the Kaplan-Meier method, and risk factors were identified by univariate and multivariate analyses. Results: Univariate Cox proportional hazard analysis revealed better overall survival (OS) for those patients who received at least 63 Gy of radiation to the primary site (P=.002), received definitive local treatment for oligometastasis (P=.041), had a Karnofsky performance status (KPS) score >80 (P=.007), had a gross tumor volume {<=}124 cm{sup 3} (P=.002), had adenocarcinoma histology (P=.002), or had no history of respiratory disease (P=.016). On multivariate analysis, radiation dose, performance status, and tumor volume retained significance (P=.004, P=.006, and P<.001, respectively). The radiation dose also maintained significance when patients with and without brain metastases were analyzed separately. Conclusions: Tumor volume, KPS, and receipt of at least 63 Gy to the primary tumor are associated with improved OS in patients with oligometastatic NSCLC at diagnosis. Our results suggest that a subset of such patients may benefit from definitive local therapy.

Napsin A levels in epithelial lining fluid as a diagnostic biomarker of primary lung adenocarcinoma.

Science.gov (United States)

Uchida, Akifumi; Samukawa, Takuya; Kumamoto, Tomohiro; Ohshige, Masahiro; Hatanaka, Kazuhito; Nakamura, Yoshihiro; Mizuno, Keiko; Higashimoto, Ikkou; Sato, Masami; Inoue, Hiromasa

2017-12-12

It is crucial to develop novel diagnostic approaches for determining if peripheral lung nodules are malignant, as such nodules are frequently detected due to the increased use of chest computed tomography scans. To this end, we evaluated levels of napsin A in epithelial lining fluid (ELF), since napsin A has been reported to be an immunohistochemical biomarker for histological diagnosis of primary lung adenocarcinoma. In consecutive patients with indeterminate peripheral lung nodules, ELF samples were obtained using a bronchoscopic microsampling (BMS) technique. The levels of napsin A and carcinoembryonic antigen (CEA) in ELF at the nodule site were compared with those at the contralateral site. A final diagnosis of primary lung adenocarcinoma was established by surgical resection. We performed BMS in 43 consecutive patients. Among patients with primary lung adenocarcinoma, the napsin A levels in ELF at the nodule site were markedly higher than those at the contralateral site, while there were no significant differences in CEA levels. Furthermore, in 18 patients who were undiagnosed by bronchoscopy and finally diagnosed by surgery, the napsin A levels in ELF at the nodule site were identically significantly higher than those at the contralateral site. In patients with non-adenocarcinoma, there were no differences in napsin A levels in ELF. The area under the receiver operator characteristic curve for identifying primary lung adenocarcinoma was 0.840 for napsin A and 0.542 for CEA. Evaluation of napsin A levels in ELF may be useful for distinguishing primary lung adenocarcinoma.

Risk evaluation - conventional and low level effects of radiation

International Nuclear Information System (INIS)

Bond, V.P.; Varma, M.N.

1984-04-01

Any discussion of the risk of exposure to potentially-hazardous agents in the environment inevitably involves the question of whether the dose effect curve is of the threshold or linear, non-threshold type. A principal objective of this presentation is to show that the function is actually two separate relationships, each representing distinctly different functions with differing variables on the axes, and each characteristic of quite different functions with differing variables on the axes, and each characteristic of quite different disciplines (i.e., the threshold function, of Pharmacology, Toxicology and Medicine [PTM]; the linear, non-threshold function, of Public Health including safety and accident statistics [PHS]). It is shown that low-level exposure (LLE) to radiation falls clearly in the PHS category. A function for cell dose vs. the fraction of single cell quantal responses is characterized, which reflects the absolute and relative sensitivities of cells. Acceptance of this function would obviate any requirement for the use in Radiation Protection of the concepts of a standard radiation, Q, dose equivalent and rem. 9 references, 4 figures

More on direct estimates of low-level radiation risks

International Nuclear Information System (INIS)

Rinsky, R.

1982-01-01

In an epidemiologic study of mortality at the Portsmouth Naval Shipyard (PNS), the National Institute for Occupational Safety and Health (NIOSH) found no evidence of excess deaths due to leukemia or other cancers among workers exposed to low levels of ionizing radiation. In a subsequent analysis, Bross and Driscoll identified excess lung cancer mortality in PNS workers with lifetime radiation dose of 1 rem or greater and with more than 15 years' latency since first radiation exposure. Although that observation may be important and is currently being examined through case-control analyses, it must be recognized that Bross and Driscoll extracted their observation from matrices of over 4,000 data cells apparently by recombination of innumerable possible permutations of dosage and latency intervals. For that reason, their finding can be regarded as no more than a suggestion for further study. It certainly does not represent a proper scientific conclusion. Bross and Driscoll's analysis illustrates the hazard of performing multiple statistical comparisons on complex data sets in the absence of a priori hypotheses

Radiation therapists' perceptions of the minimum level of experience required to perform portal image analysis

Energy Technology Data Exchange (ETDEWEB)

Rybovic, Michala [Discipline of Medical Radiation Sciences, Faculty of Health Sciences, University of Sydney, PO Box 170, Lidcombe, NSW 1825 (Australia)], E-mail: mryb6983@mail.usyd.edu.au; Halkett, Georgia K. [Western Australia Centre for Cancer and Palliative Care, Curtin University of Technology, Health Research Campus, GPO Box U1987, Perth, WA 6845 (Australia)], E-mail: g.halkett@curtin.edu.au; Banati, Richard B. [Faculty of Health Sciences, Brain and Mind Research Institute - Ramaciotti Centre for Brain Imaging, University of Sydney, PO Box 170, Lidcombe, NSW 1825 (Australia)], E-mail: r.banati@usyd.edu.au; Cox, Jennifer [Discipline of Medical Radiation Sciences, Faculty of Health Sciences, University of Sydney, PO Box 170, Lidcombe, NSW 1825 (Australia)], E-mail: jenny.cox@usyd.edu.au

2008-11-15

Background and purpose: Our aim was to explore radiation therapists' views on the level of experience necessary to undertake portal image analysis and clinical decision making. Materials and methods: A questionnaire was developed to determine the availability of portal imaging equipment in Australia and New Zealand. We analysed radiation therapists' responses to a specific question regarding their opinion on the minimum level of experience required for health professionals to analyse portal images. We used grounded theory and a constant comparative method of data analysis to derive the main themes. Results: Forty-six radiation oncology facilities were represented in our survey, with 40 questionnaires being returned (87%). Thirty-seven radiation therapists answered our free-text question. Radiation therapists indicated three main themes which they felt were important in determining the minimum level of experience: 'gaining on-the-job experience', 'receiving training' and 'working as a team'. Conclusions: Radiation therapists indicated that competence in portal image review occurs via various learning mechanisms. Further research is warranted to determine perspectives of other health professionals, such as radiation oncologists, on portal image review becoming part of radiation therapists' extended role. Suitable training programs and steps for implementation should be developed to facilitate this endeavour.

Resistance of Feather-Associated Bacteria to Intermediate Levels of Ionizing Radiation near Chernobyl

OpenAIRE

Ruiz-Gonz?lez, Mario Xavier; Czirj?k, G?bor ?rp?d; Genevaux, Pierre; M?ller, Anders Pape; Mousseau, Timothy Alexander; Heeb, Philipp

2016-01-01

Ionizing radiation has been shown to produce negative effects on organisms, although little is known about its ecological and evolutionary effects. As a study model, we isolated bacteria associated with feathers from barn swallows Hirundo rustica from three study areas around Chernobyl differing in background ionizing radiation levels and one control study site in Denmark. Each bacterial community was exposed to four different ? radiation doses ranging from 0.46 to 3.96 kGy to test whether ch...

Radiation level analysis for the port cell of the ITER electron cyclotron-heating upper launcher

Energy Technology Data Exchange (ETDEWEB)

Weinhorst, Bastian, E-mail: bastian.weinhorst@kit.edu [KIT, Institute for Neutron Physics and Reactor Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Fischer, Ulrich; Lu, Lei [KIT, Institute for Neutron Physics and Reactor Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Strauss, Dirk; Spaeh, Peter; Scherer, Theo [KIT, Institute for Applied Materials, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Leichtle, Dieter [F4E, Analysis & Codes/Technical Support Services, Josep Pla 2, Torres Diagonal Litoral B3, 08019 Barcelona (Spain)

2016-11-01

Highlights: • First detailed neutronic modelling of the ECHUL port cell with ECHUL equipment (including beam lines with diamond windows, the beam lines mounting box, conduit boxes and rails). • Three different bioshield port plug configurations and two different neutron source configurations are investigated. • Radiation Levels are calculated in the port cell, focusing on the position of the diamond window. • The dose rate in the port cell is below the limit for maintenance in the port cell. • The radiation level at the diamond window is very low and should not influence its performance. - Abstract: The electron cyclotron-heating upper launcher (ECHUL) will be installed in four upper ports of the ITER tokamak thermonuclear fusion reactor. Each ECHUL is able to deposit 8 MW power into the plasma for plasma mode stabilization via microwave beam lines. An essential part of these beam lines are the diamond windows. They are located in the upper port cell behind the bioshield to reduce the radiation levels to a minimum. The paper describes the first detailed neutronic modelling of the ECHUL port cell with ECHUL equipment. The bioshield plug is modelled including passageways for the microwave beam lines, piping and cables looms as well as rails and openings for ventilation. The port cell is equipped with the beam lines including the diamond windows, the beam lines mounting box, conduit boxes and rails. The neutrons are transported into the port cell starting from a surface source in front of the bioshield. Neutronic results are obtained for radiation levels in the port cell at different positions, mainly focusing on the diamond windows position. It is shown that the radiation level is below the limit for maintenance in the port cell. The radiation level at the diamond window is very low and should not influence its performance.

Assessment of environmental gamma radiation levels at locations having different source characteristics using TLDs

International Nuclear Information System (INIS)

Sahu, S.K.; Swarnkar, M.; Takale, R.A.; Shetty, P.G.; Pandit, G.G.; Puranik, V.D.

2012-01-01

Naturally occurring radionuclides are the major contributor to the total effective dose of ionizing radiation received by the population (UNSCEAR, 1993). The dose in environment thus depends largely on natural radiation than manmade or artificially produced radiation. In the last few decades, there is a growing concern all over the world about radiation and their exposure to population. Thus, it is a necessity to conduct frequent radiological environmental surveillance in order to assess population exposure accurately. Recently, application of thermoluminescence dosimeters (TLDs) has been extended to the measurement of mixed radiation field as encountered in the environment. The advantages of passive TL dosimeters for environmental monitoring are that they are small, cheap and do not require power supply during application. The passive TL dosimeters play an important role to provide data on natural background radiation and to determine the contribution to the dose to public from man-made sources. In the present study, three different sites were chosen to compare environmental gamma radiation levels in different scenarios. Kaiga has been chosen as site 1, where four unit of pressurized heavy water reactor (PHWR) of 220 MWe each are in operation. Site 2 is chosen at natural high background radiation area (NHBRA) of Kerala and Vishakhapatnam was chosen as site 3, which is situated at a normal background area. The objective of the study is to illustrate the effect, if any, of an operating nuclear power reactor on environmental gamma radiation levels

Development of an omnidirectional gamma-ray imaging Compton camera for low-radiation-level environmental monitoring

Science.gov (United States)

Watanabe, Takara; Enomoto, Ryoji; Muraishi, Hiroshi; Katagiri, Hideaki; Kagaya, Mika; Fukushi, Masahiro; Kano, Daisuke; Satoh, Wataru; Takeda, Tohoru; Tanaka, Manobu M.; Tanaka, Souichi; Uchida, Tomohisa; Wada, Kiyoto; Wakamatsu, Ryo

2018-02-01

We have developed an omnidirectional gamma-ray imaging Compton camera for environmental monitoring at low levels of radiation. The camera consisted of only six CsI(Tl) scintillator cubes of 3.5 cm, each of which was readout by super-bialkali photo-multiplier tubes (PMTs). Our camera enables the visualization of the position of gamma-ray sources in all directions (∼4π sr) over a wide energy range between 300 and 1400 keV. The angular resolution (σ) was found to be ∼11°, which was realized using an image-sharpening technique. A high detection efficiency of 18 cps/(µSv/h) for 511 keV (1.6 cps/MBq at 1 m) was achieved, indicating the capability of this camera to visualize hotspots in areas with low-radiation-level contamination from the order of µSv/h to natural background levels. Our proposed technique can be easily used as a low-radiation-level imaging monitor in radiation control areas, such as medical and accelerator facilities.

Study of Radiation Shielding Analysis for Low-Intermediate Level Waste Transport Ship

Energy Technology Data Exchange (ETDEWEB)

Kim, Dohyung; Lee, Unjang; Song, Yangsoo; Kim, Sukhoon; Ko, Jaehoon [Korea Nuclear Engineering and Service Corporation, Seoul (Korea, Republic of)

2007-07-01

In Korea, it is planed to transport Low-Intermediate Level Radioactive Waste (LILW) from each nuclear power plant site to Kyongju LILW repository after 2009. Transport through the sea using ship is one of the most prospective ways of LILW transport for current situation in Korea. There are domestic and international regulations for radiation dose limit for radioactive material transport. In this article, radiation shielding analysis for LILW transport ship is performed using 3-D computer simulation code, MCNP. As a result, the thickness and materials for radiation shielding walls next to cargo in the LILW transport ship are determined.

Analysis of cosmetic results following primary radiation therapy for stages I and II carcinoma of the breast

International Nuclear Information System (INIS)

Harris, J.R.; Levene, M.B.; Svensson, G.; Hellman, S.

1979-01-01

In 31 cases of Stages I or II carcinoma of the breast treated by primary radiation therapy, the cosmetic results were analyzed with regard to the details of treatment. Three principal treatment factors were identified which influenced the cosmetic outcome: (1) the extent and location of the biopsy procedure; (2) the time/dose factors of the radiation therapy; and (3) the technique of the radiation therapy. Cosmetic results were lessened when the biopsy procedure included a wide resection of adjacent breast tissue or when the biopsy scar was obvious. Increasing doses of external beam radiation were associated with greater degrees of retraction and fibrosis of the treated breast. All 6 patients who received 6000 rad by external beam had significant retraction, and fibrosis while patients who received 5000 rad rarely showed significant changes. Local boost doses by interstitial implantation did not diminsh the cosmetic outcome. All patients were treated using supervoltage equipment without bolus and skin changes secondary to treatment were infrequent. Seventeen patients developed localized areas of fibrosis and skin changes at the matchline between adjacent radiation fields. Recommendations are made for improved cosmetic results based on these findings

Health effects of low-level ionizing radiation

International Nuclear Information System (INIS)

Fabrikant, J.I.

1979-04-01

It is now assumed that any exposure to radiaton at low levels of dose carries some risk of deleterious effects. How low this level may be, or the probability or magnitude of the risk, still are not known. Our best scientific knowledge and advice are essential for the protection of the public health, for the effective application of new technologies in medicine and industry and for guidance in the production of nuclear energy. Unless man wishes to dispense with those activities which inevitably involve exposure to low levels of ionizing radiations, he must recognize that some degree of risk to health, however small, exists. A pragmatic appraisal of how man wishes to continue to derive the benefits of health and happiness from such activities involving ionizing radiaton in times of everchanging conditions and public attitudes in our resource-limited society is the task which lies before all of us - all men and women of our society, of science and of medicine, and of law and government - now and in the future

Effect of Cell-Phone Radiation in Pregnancy on Serum Levels of Sexual Hormones and Dynastic Cells in adult Female Offspring in Rats

Directory of Open Access Journals (Sweden)

ebrahim Hosseini

2016-04-01

Full Text Available Background & objectives: The teratogenic effects of electromagnetic radiation on different processes of growth caused many concerns related to the harmful effects of cell-phone radiation on human health. Therefore, the aim of this study was to investigate the effects of cell-phone radiation on estrogen, progesterone, FSH and LH hormones together with dynastic sexual cells of adult female offspring of pregnant rats affected by these radiations. Methods: In this experimental study, 24 pregnant female rats divided into 3 groups including the control, sham and experimental groups were used. The control group received no radiation and the experimental group was exposed to cell-phone radiation at the beginning of pregnancy (4 hours daily for 14 days. The control group was exposed around turning-on cell-phone without conversation over the same period. After giving birth and after maturity, 10 female offsprings of different groups separated and after phlebotomizing, sexual hormones levels was measured and by separating the ovaries, ovarian follicles species were counted. The results analyzed using ANOVA and T tests. Differences in statistical analysis of data were considered significant at p<0.05. Results: The results showed that the pregnant female exposure to cell-phone radiation caused significant increase in the size and weight of the ovaries and atresic follicles (p<0.05 without significant effect on the number of primary and secondary follicles, antral, graph, primordial, corpus luteum and sexual hormones. Conclusion: Exposure to cell-phone radiations caused increase in the size, weight and atresic follicles of offspring’s ovaries in pregnant females

Investigation of environmental natural penetrating radiation level in Hubei Province

International Nuclear Information System (INIS)

Zhang Sihui; Zhang Jiaxian

1992-01-01

The methods and results of the investigation on natural penetrating radiation level in Hubei Province are presented, 290 measuring points of 25 x 25 km-grid were set uniformly up all over the province, with 385 densely measuring points of different types added. The results show that: (1) The area-weighted, population-weighted and point-weighted average value of natural γ radiation dose rate for field is 60.8, 58.5 and 60.9 nGy ·h -1 , respectively; (2) The point-weighted average value of natural γ radiation dose rate for road is 55.3 nGy·h -1 ; (3) The population-weighted and point-weighed average value of natural γ radiation dose rate inside buildings is 94.5 and 93.2 x 10 nGy·h -1 , respectively; (4) The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 27.8 and 26.3 nGy·h -1 , and outside buildings is 31.8 and 30.4 nGy·h -1 , respectively; (5) The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside building is 121.0 and 120.7 nGy·h -1 , outside buildings is 92.8 and 88.9 nGy·h -1 , respectively; (6) The annual effective dose equivalent from cosmic ray, natural γ radiation and natural penetrating radiation is 0.24, 0.52 and 0.76 mSv, respectively; and correspondingly, the annual collective effective dose equivalent is 1.2, 2.5 and 3.7 x 10 4 man·Sv, respectively

Investigation of environmental natural penetrating radiation level in Heilongjiang Province

International Nuclear Information System (INIS)

Liu Yuncheng; Wu Chengxiang; Zhang Juling; Zhao Defeng

1994-01-01

The methods and results of the investigation on natural penetrating radiation level in Heilongjiang Province are presented. 221 25 km x 25 km-grid measuring points were set uniformly up all over the province, with 555 densely measuring points of different types added. The results show that: (1)The area-weighted, population-weighted and point-weighted average value of natural γ radiation dose rate for field is 53.5, 58.5 and 54.2 nGy·h -1 , respectively; (2) The point-weighted average value of natural γ radiation dose rate for road is 58.4 nGy·h -1 ; (3) The population-weighted and point-weighted average value of natural γ radiation dose rate inside buildings is 85.2 and 78.9 nGy·h -1 , respectively; (4) The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 28.6 and 28.1 nGy·h -1 , and outside buildings is 32.4 and 32.2 nGy·h -1 , respectively; (5) The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside buildings is 109.7 and 112.8 nGy·h -1 , outside buildings is 84.8 and 91.0 nGy·h -1 , respectively; (6) The annual effective dose equivalent from cosmic ray, natural γ radiation and natural penetrating radiation is 0.26, 0.48 and 0.73 mSv, respectively; and correspondingly, the annual collective effective dose equivalent is 0.8 x 10 4 , 1.6 x 10 4 and 2.4 x 10 4 man·Sv, respectively

Investigation of environmental natural penetrating radiation level in Jiangsu province

International Nuclear Information System (INIS)

Liu Ming; Wang Chengbao.

1993-01-01

The methods and results of in investigation on natural penetrating radiation level in Jiangsu Province are presented. 182 25 km x 25 km-grid measuring points were set up uniformly all over the province, with 236 densely measuring points of different types added. The results show that: (1) The area-weighted, population-weighted and point-weighted average value of natural γ radiation dose rate for field is 50.3, 50.6 and 50.4 nGy · h -1 , respectively; (2) The point-weighted average value of natural γ radiation dose rate for road is 47.1 nGy · h -1 ; (3) The population-weighted and point-weighted average value of natural γ radiation dose rate inside buildings is 89.7 and 89.2 nGy · h -1 , respectively; (4) The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 26.0 and 25.8 nGy · h -1 , and outside buildings is 29.2 and 29.1 nGy · h -1 , respectively; (5) The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside buildings is 115.1 and 115.5 nGy · h -1 , outside buildings is 79.5 and 79.7 nGy · h -1 , respectively; (6) The annual effective dose equivalent from cosmic ray, natural γ radiation and natural penetrating radiation is 0.23, 0.48 and 0.71 mSv, respectively; and correspondingly, the annual collective effective dose equivalent is 3.0, 1.5 and 4.5 x 10 4 man · Sv, respectively

Investigation of environmental natural penetrating radiation level in Shaanxi Province

International Nuclear Information System (INIS)

Zhang Chunfang; Li Jiyin

1994-01-01

The methods and results of the investigation on natural penetrating radiation level in Shaanxi Province are presented. 359 25 km x 25 km-grid measuring points were set uniformly up all over the province, with 433 densely measuring points of different types added. The results show that: (1) The area-weighted, population-weighted and point-weighted average value of natural γ radiation dose rate for field is 62.0, 63.0 and 61.0 nGy·h -1 , respectively; (2) The point-weighted average value of natural γ radiation dose rate for road is 63.0 nGy · h -1 ; (3)The population-weighted and point-weighted average value of natural γ radiation dose rate inside buildings is 100.0 and 98.0 nGy·h -1 , respectively; (4)The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 32.0 and 31.0 nGy·h -1 , and outside buildings is 37.0 and 36.0 nGy·h -1 , respectively; (5)The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside buildings is 130.0 and 131.0 nGy·h -1 , outside buildings is 130.0 and 130.0 nGy·h -1 , respectively; (6)The annual effective dose equivalent from cosmic ray, natural γ radiation and natural penetrating radiation is 0.55, 0.28 and 0.83 mSv, respectively; and correspondingly, the annual collective effective dose equivalent is 1.63, 0.83 and 2.46 x 10 4 man·Sv, respectively

Modulation of DNA methylation levels sensitizes doxorubicin-resistant breast adenocarcinoma cells to radiation-induced apoptosis

Energy Technology Data Exchange (ETDEWEB)

Luzhna, Lidia [Department of Biological Sciences, University of Lethbridge, AB, Canada T1K 3M4 (Canada); Kovalchuk, Olga, E-mail: olga.kovalchuk@uleth.ca [Department of Biological Sciences, University of Lethbridge, AB, Canada T1K 3M4 (Canada)

2010-02-05

Chemoresistant tumors often fail to respond to other cytotoxic treatments such as radiation therapy. The mechanisms of chemo- and radiotherapy cross resistance are not fully understood and are believed to be epigenetic in nature. We hypothesize that MCF-7 cells and their doxorubicin-resistant variant MCF-7/DOX cells may exhibit different responses to ionizing radiation due to their dissimilar epigenetic status. Similar to previous studies, we found that MCF-7/DOX cells harbor much lower levels of global DNA methylation than MCF-7 cells. Furthermore, we found that MCF-7/DOX cells had lower background apoptosis levels and were less responsive to radiation than MCF-7 cells. Decreased radiation responsiveness correlated to significant global DNA hypomethylation in MCF-7/DOX cells. Here, for the first time, we show that the radiation resistance of MCF-7/DOX cells can be reversed by an epigenetic treatment - the application of methyl-donor SAM. SAM-mediated reversal of DNA methylation led to elevated radiation sensitivity in MCF-7/DOX cells. Contrarily, application of SAM on the radiation sensitive and higher methylated MCF-7 cells resulted in a decrease in their radiation responsiveness. This data suggests that a fine balance of DNA methylation is needed to insure proper radiation and drug responsiveness.

Measurement of the solar ultraviolet radiation at ground level in Bangi, Malaysia

Energy Technology Data Exchange (ETDEWEB)

Aljawi, Ohoud; Gopir, Geri; Duay, Abdul Basit [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia. ohoud-aljawi@hotmail.com (Malaysia)

2015-04-24

Understanding the amount of ultraviolet (UV) radiation received by human, plant, and animal organisms near the earth’s surface is important to a wide range of fields such as cancer research, agriculture and forestry. The solar ultraviolet spectral irradiance at ground level was measured using the Avantes spectrometer for the period of January to March 2014 at Bangi (2°55´N, 101°46´E, 50 m above sea level) in Malaysia. These data were used to estimate the diurnal variation of UV irradiance (300 – 400 nm). The maximum irradiance of UV radiation was 45 W m{sup −2} on horizontal surface. The maximum irradiance of UV received in the local noon time, and the minimum values of UV irradiance was received in the local morning time. It is found a bigger value of UV radiation was observed on clear sky in January. The estimation of daily flux average of UV irradiance was (921± 91) kJ m{sup −2}.

BWR radiation exposure--experience and projection

International Nuclear Information System (INIS)

Falk, C.F.; Wilkinson, C.D.; Hollander, W.R.

1979-01-01

The BWR/6 Mark III radiation exposures are projected to be about half of those of current average operating experience of 725 man-rem. These projections are said to be realistic and based on current achievements and not on promises of future development. The several BWRs operating with low primary system radiation levels are positive evidence that radiation sources can be reduced. Improvements have been made in reducing the maintenance times for the BWR/6, and further improvements can be made by further attention to cost-effective plant arrangement and layout during detail design to improve accessibility and maintainability of each system and component

An evaluation of primary school students' views about noise levels in school

Directory of Open Access Journals (Sweden)

Nermin Bulunuz

2017-06-01

Full Text Available Effective education and teaching requires keeping classroom noise levels within specific limits. The purpose of this study is to evaluate students’ views about the noise level in school, its effects, and control of it at two primary schools (one public school and one private school located in a district of Bursa - within the scope of the TÜBİTAK 1001 project numbered 114K738. The research sample consists of 432 third and fourth graders, 223 of whom are from the public school and 209 of whom are from the private school. To collect data, a 20-question survey was administered to the students, and noise measurements were carried out in the schools. According to the findings obtained from the analysis of the answers from the student questionnaire, the students think that the noise level is high especially during break times. In parallel with the student views, the average noise level at break time during recess was found to be 74.56 dBA at the private primary school and 82.18 dBA at the public primary school. These values are much higher than the limits prescribed in the Regulation on Assessment and Management of Environmental Noise in Turkey (RAMEN European Union Harmonization Laws. The research findings show that this important problem must be dealt with urgently, and substantive efforts and activities must be launched to reduce high noise levels in schools.

The Role of Pre-School Education on Learning Achievement at Primary Level in Bangladesh

Science.gov (United States)

Nath, Samir Ranjan

2012-01-01

This paper examines the impact of pre-school education on learning achievement at primary level in Bangladesh. Evidence from learning achievement test and household and school-related data were obtained from 7093 pupils attending 440 primary schools in Bangladesh. Findings suggest that a small proportion (15.3%) of primary school pupils attended…

The Australasian radiation protection society's position statement on risks from low levels of ionizing radiation

Energy Technology Data Exchange (ETDEWEB)

Don, Higson; Ches, Mason; Andrew, McEwan; Peter, Burns; Riaz, Akber; Ron, Cameron; Pamela, Sykes; Joe, Young [Australasian Radiation Protection Society (Australia)

2006-07-01

At its Annual General Meeting in 2004, the Australasian Radiation Protection Society (A.R.P.S.) set up a working group to draft a statement of the Society's position on risks from low levels of exposure to ionizing radiation. The resulting position statement was adopted by the Society at its Annual General Meeting in 2005. Its salient features are as follows: First, there is insufficient evidence to establish a dose-effect relationship for doses that are less than a few tens of milli sieverts in a year. A linear extrapolation from higher dose levels should be assumed only for the purpose of applying regulatory controls. Secondly, estimates of collective dose arising from individual doses that are less than some tens of milli sieverts in a year should not be used to predict numbers of fatal cancers. Thirdly, the risk to an individual of doses significantly less than 100 micro sieverts in a year is so small, if it exists at all, that regulatory requirements to control exposure at this level are not warranted. (authors)

Tradescantia in studies of genetic effects of low level radiation

International Nuclear Information System (INIS)

Yamashita, Atsushi

1976-01-01

Tradescantia in studies on genetic effects of low level radiation is briefly introduced. Radiosensitivity, method of screening stamen hair mutation, materials in current uses, spontaneous mutation rate, and modifying factors are refered. For stamen hair mutation b values in exponential model were lower in irradiation with low dose rate at high environmental temperature. The dose response curves under these modifying conditions, when extrapolated to low dose range, well fit to the line which was obtained by Sparrow's experiment of low level irradiation. In chronic irradiation, the frequency of stamen hair mutation reaches to the constant value after 17 days from the start of irradiation, and is as much as 4 times higher than the peak value in one day irradiation at the same exposure rate. The spontaneous mutation rate of KU-7 varied with temperature. The increase with 1 0 C increment of mean temperature was -0.04%. Uses of Tradescantia in monitoring the environmental radiation is discussed. (auth.)

Exposing primary rat retina cell cultures to γ-rays: An in vitro model for evaluating radiation responses.

Science.gov (United States)

Gaddini, Lucia; Balduzzi, Maria; Campa, Alessandro; Esposito, Giuseppe; Malchiodi-Albedi, Fiorella; Patrono, Clarice; Matteucci, Andrea

2018-01-01

Retinal tissue can receive incidental γ-rays exposure during radiotherapy either of tumors of the eye and optic nerve or of head-and-neck tumors, and during medical diagnostic procedures. Healthy retina is therefore at risk of suffering radiation-related side effects and the knowledge of pathophysiological response of retinal cells to ionizing radiations could be useful to design possible strategies of prevention and management of radiotoxicity. In this study, we have exploited an in vitro model (primary rat retinal cell culture) to study an array of biological effects induced on retinal neurons by γ-rays. Most of the different cell types present in retinal tissue - either of the neuronal or glial lineages - are preserved in primary rat retinal cultures. Similar to the retina in situ, neuronal cells undergo in vitro a maturational development shown by the formation of polarized neuritic trees and operating synapses. Since 2 Gy is the incidental dose received by the healthy retina per fraction when the standard treatment is delivered to the brain, retina cell cultures have been exposed to 1 or 2 Gy of γ-rays at different level of neuronal differentiation in vitro: days in vitro (DIV)2 or DIV8. At DIV9, retinal cultures were analyzed in terms of viability, apoptosis and characterized by immunocytochemistry to identify alterations in neuronal differentiation. After irradiation at DIV2, MTT assay revealed an evident loss of cell viability and βIII-tubulin immunostaining highlighted a marked neuritic damage, indicating that survived neurons showed an impaired differentiation. Differentiated cultures (DIV8) appeared to be more resistant with respect to undifferentiated, DIV2 cultures, both in terms of cell viability and differentiation. Apoptosis evaluated with TUNEL assay showed that irradiation at both DIV2 and DIV8 induced a significant increase in the apoptotic rate. To further investigate the effects of γ-rays on retinal neurons, we evaluated the

The Role Of Sevoflurane And Ionising Radiation On THE Level Of Primary DNA Damage Measured In Blood And Different Organs Of Swiss Albino Mice By THE Alkaline Comet Assay

International Nuclear Information System (INIS)

Benkovic, V.; Milic, M.; Horvat Knezevic, A.; Halovanovic, S.; Borojevic, N.; Orsolic, N.

2015-01-01

Sevoflurane is general anaesthetic suitable for short surgical procedures due to its quick induction of anaesthesia, maintaining spontaneous breathing frequency and hemodynamic stability of patients. However, it can directly trigger the formation of peroxynitrite, significantly increase intracellular levels of H2O2, peroxide, superoxide anion and nitric oxide in peripheral polymorphonuclear neutrophils 1h after the treatment; lowering the levels of intracellular glutathione, and increase radiosensitivity of cells also exposed to ionising radiation (IR). We wanted to evaluate the level of sinergistic effect and possible radiosensitivity DNA damage in blood, and different organs of Swiss albino mice after exposure to both sevoflurane (2.4 percent, 50:50) and the 1Gy gamma-ray radiation generally used in diagnostic purposes after 0, 2, 6 and 24 hours from the combined treatment with alkaline comet assay. Combined exposure to sevoflurane and IR has demonstrated synergistic effect. Due to metabolising of the sevoflurane, there was different sensitivity between blood, liver, kidney and brain cells. (author).

Ambient radiation levels in a microPET/CT research laboratory

Energy Technology Data Exchange (ETDEWEB)

Sarmento, D.M.; Rodrigues, D.L.; Sanches, M.P.; Carneiro, J.C.G.G., E-mail: janetegc@ipen.br [Instituto de Pesquisas Energeticas e Nucleres (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

This study focuses on initial radiological evaluation and the exposure situation related to the worker task in a micro-positron emission tomography/computed tomography laboratory (microPET/CT). Selected and calibrated thermoluminescent dosimeters, TLD, of CaSO{sub 4}:Dy were used to measure room radiation levels. The detectors were placed in several selected points inside the microPET/CT laboratory and adjacent rooms. In addition, the occupationally exposed workers were monthly evaluated for external and internal exposures. In none of the selected points the dose values exceeded the radiation dose limit established for supervised area, as well as the values obtained in individual monitoring. (author)

Ambient radiation levels in a microPET/CT research laboratory

International Nuclear Information System (INIS)

Sarmento, D.M.; Rodrigues, D.L.; Sanches, M.P.; Carneiro, J.C.G.G.

2015-01-01

This study focuses on initial radiological evaluation and the exposure situation related to the worker task in a micro-positron emission tomography/computed tomography laboratory (microPET/CT). Selected and calibrated thermoluminescent dosimeters, TLD, of CaSO 4 :Dy were used to measure room radiation levels. The detectors were placed in several selected points inside the microPET/CT laboratory and adjacent rooms. In addition, the occupationally exposed workers were monthly evaluated for external and internal exposures. In none of the selected points the dose values exceeded the radiation dose limit established for supervised area, as well as the values obtained in individual monitoring. (author)

Investigation of environmental natural penetrating radiation level in Hebei province

International Nuclear Information System (INIS)

Zheng Deliang; Wang Shuming; Yang Huanfeng

1990-01-01

The methods and results of the investigation on natural penetrating radiation level in Hebei Province from 1985 to 1987 are presented. 285 25 x 25 km-netted measuring points were set unformly up all over the porvince, with 204 densely measuring points of different types added. The results show that: (1) The point-weighted, area-weighted and population-weighted average value of natural γ radiation dose rate for field is 5.59, 5.51 and 5.31 x 10 -8 Gy·h -1 , respectively; (2) The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 3.05 and 2.80 x 10 -8 Gy·h -1 , and outside buildings is 3.38 and 3.11 x 10 -8 Gy·h -1 , respectively; (3) The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside buildings is 12.44 and 11.97 x 10 -8 Gy·h -1 , outside buildings is 8.97 and 8.42 x 10 -8 Gy·h -1 , respectively; (4) The annual effective dose equivalent from natural γ radiation, cosmic ray and natural penetrating radiation is 0.50, 0.25, and 0.75 mSv, respectively; and correspondingly, the annual collective effectiv dose equivalent is 2.7, 1.3 and 4.0 x 10 4 man·Sv, respectively

New aspects on the contribution of primary defects in silicon due to long-time degradation of detectors operating in high fields of radiation

International Nuclear Information System (INIS)

Lazanu, Sorina; Lazanu, Ionel

2006-01-01

Full text: Silicon detectors will represent an important option for the next generation of experiments in high energy physics, for astroparticle and nuclear experiments, where the requirements to operate long time in high radiation environments will represent a major problem. After the long-time operation in high radiation fields, the bulk displacement damage produces the following effects at the device level: increase of the leakage current, decrease of the satisfactory Signal/Noise ratio, increase of the effective carrier concentration, and thus of the depletion voltage, decrease of the charge collection efficiency up to unacceptable levels. In this contribution we investigate the new perspective in understanding the fundamental phenomena in silicon and implications for the degradation of the characteristics of detectors given by the consideration of the existence of the new primary defect: fourfold coordinated defect, Si FFCD , with a lower value of the formation energy by comparison with the 'classically' known vacancies and interstitials. Predicted by Goedecker and co-workers, its characteristics were indirectly determined by Lazanu and Lazanu. The correlation between the rate of generation of primary defects, material composition and observable effects is investigated considering different growth technologies and resistivities (up to tens of kΩcm) as time and fluence dependencies. This allows to estimate the expected behaviour of the materials and detectors in concrete environments at the next generations of high energy physics experiments as SLHC or VLHC for example. This new defect could represent the elementary block for new extended defects and in principle it could generate local amorphization of the semiconductor. Its existence and characteristics in other semiconductors is also investigated. (author)

assessment of the english literacy level of patients in primary health ...

African Journals Online (AJOL)

2010-09-07

Sep 7, 2010 ... The English literacy level of primary health care patients in Tshwane .... It is therefore important to use appropriate literacy assessment tools to .... Participants were given the following instruction: ..... One of the disadvantages.

Primary cutaneous lymphoma

International Nuclear Information System (INIS)

Nguyen, M. Connie; Cleary, Sean F.; Hoppe, Richard T.

1995-01-01

Purpose: A retrospective review analyzed the survival and freedom from relapse of patients with stage IE or IIE primary cutaneous lymphoma (non mycosis fungoides) after treatments with radiation therapy alone (XRT), chemotherapy alone (RX) or combined modality therapy (CMT). Methods and Materials: Fifty two patients with stage IE-IIE cutaneous lymphoma treated at Stanford University Hospital were reviewed. The median age was 57, with a range of 26 to 94 and a male to female ratio of 1.21:1. Patients were staged according to the Ann Arbor System. Pathology was classified according to the Working Formulation. Treatment outcomes were compared using Kaplan-Meier survival curves with a Gehan p-value test. Results: The follow up range was 6 months to 22 years (median 7 years.) Twenty one percent of patients had low grade, 63% had intermediate grade and 15% had high grade lymphoma. The most common histologic subtype was diffuse large cell lymphoma Thirty two patients received radiation alone as initial treatment and sixteen patients received combined modality as initial treatment. Four patients received chemotherapy alone. The only significant prognostic factor for survival was the stage at diagnosis. Patients with stage IE disease had a longer actuarial survival (5-yr=79%, 10-yr=71%), as compared to those with stage IIE (5-yr=49%, 10-yr=33%), (p=0.029). The only significant prognostic factor for freedom from relapse was the initial treatment. Initial combined modality treatment lead to a longer freedom from relapse compared to patients treated with radiation alone (p=0.002), (median 5 years vs. 1.2 years). Despite this, the actuarial overall survival in the combined modality group and the radiation alone group are similar (median survival 7.7 and 8 years). The efficacy of either radiation or chemotherapy as salvage treatment after radiation failure was equivalent and both salvage treatments lead to equally long survival and freedom from second relapse. Conclusion

Primary cutaneous lymphoma

Energy Technology Data Exchange (ETDEWEB)

Nguyen, M Connie; Cleary, Sean F; Hoppe, Richard T

1995-07-01

Purpose: A retrospective review analyzed the survival and freedom from relapse of patients with stage IE or IIE primary cutaneous lymphoma (non mycosis fungoides) after treatments with radiation therapy alone (XRT), chemotherapy alone (RX) or combined modality therapy (CMT). Methods and Materials: Fifty two patients with stage IE-IIE cutaneous lymphoma treated at Stanford University Hospital were reviewed. The median age was 57, with a range of 26 to 94 and a male to female ratio of 1.21:1. Patients were staged according to the Ann Arbor System. Pathology was classified according to the Working Formulation. Treatment outcomes were compared using Kaplan-Meier survival curves with a Gehan p-value test. Results: The follow up range was 6 months to 22 years (median 7 years.) Twenty one percent of patients had low grade, 63% had intermediate grade and 15% had high grade lymphoma. The most common histologic subtype was diffuse large cell lymphoma Thirty two patients received radiation alone as initial treatment and sixteen patients received combined modality as initial treatment. Four patients received chemotherapy alone. The only significant prognostic factor for survival was the stage at diagnosis. Patients with stage IE disease had a longer actuarial survival (5-yr=79%, 10-yr=71%), as compared to those with stage IIE (5-yr=49%, 10-yr=33%), (p=0.029). The only significant prognostic factor for freedom from relapse was the initial treatment. Initial combined modality treatment lead to a longer freedom from relapse compared to patients treated with radiation alone (p=0.002), (median 5 years vs. 1.2 years). Despite this, the actuarial overall survival in the combined modality group and the radiation alone group are similar (median survival 7.7 and 8 years). The efficacy of either radiation or chemotherapy as salvage treatment after radiation failure was equivalent and both salvage treatments lead to equally long survival and freedom from second relapse. Conclusion

Radiation effects in glass waste forms for high-level waste and plutonium disposal

International Nuclear Information System (INIS)

Weber, W.J.; Ewing, R.C.

1997-01-01

A key challenge in the permanent disposal of high-level waste (HLW), plutonium residues/scraps, and excess weapons plutonium in glass waste forms is the development of predictive models of long-term performance that are based on a sound scientific understanding of relevant phenomena. Radiation effects from β-decay and α-decay can impact the performance of glasses for HLW and Pu disposition through the interactions of the α-particles, β-particles, recoil nuclei, and γ-rays with the atoms in the glass. Recently, a scientific panel convened under the auspices of the DOE Council on Materials Science to assess the current state of understanding, identify important scientific issues, and recommend directions for research in the area of radiation effects in glasses for HLW and Pu disposition. The overall finding of the panel was that there is a critical lack of systematic understanding on radiation effects in glasses at the atomic, microscopic, and macroscopic levels. The current state of understanding on radiation effects in glass waste forms and critical scientific issues are presented

Soybean growth responses to enhanced levels of ultraviolet-B radiation under greenhouse conditions

International Nuclear Information System (INIS)

Teramura, A.H.; Sullivan, J.H.

1987-01-01

Soybean (Glycine max [L.] Merr. cv. Essex) was grown in an unshaded greenhouse under three levels of biologically effective ultraviolet-B (UV-BBE) radiation (effective daily dose: 0, 11.5 and 13.6 kJ m -2 ) for 91 days. Plants were harvested at regular intervals beginning 10 days after germination until reproductive maturity. Mathematical growth analysis revealed that the effects of UV-B radiation varied with plant growth stage. The transition period between vegetative and reproductive growth was the most sensitive to UV-B radiation. Intermediate levels of UV-B had deleterious effects on plant height, leaf area, and total plant dry weight at late vegetative and reproductive stages of development. Specific leaf weight increased during vegetative growth but was unaffected by UV-B during reproductive growth stages. Relative growth, net assimilation, and stem elongation rates were decreased by UV-B radiation during vegetative and early reproductive growth stages. Variation in plant responses may be due in part to changes in microclimate within the plant canopy or to differences in repair or protection mechanisms at differing developmental stages. (author)

Safety of dose escalation by simultaneous integrated boosting radiation dose within the primary tumor guided by 18FDG-PET/CT for esophageal cancer

International Nuclear Information System (INIS)

Yu, Wen; Cai, Xu-Wei; Liu, Qi; Zhu, Zheng-Fei; Feng, Wen; Zhang, Qin; Zhang, Ying-Jian; Yao, Zhi-Feng; Fu, Xiao-Long

2015-01-01

Purpose: To observe the safety of selective dose boost to the pre-treatment high 18 F-deoxyglucose (FDG) uptake areas of the esophageal GTV. Methods: Patients with esophageal squamous cell carcinoma were treated with escalating radiation dose of 4 levels, with a simultaneous integrated boost (SIB) to the pre-treatment 50% SUVmax area of the primary tumor. Patients received 4 monthly cycles of cisplatin and fluorouracil. Dose-limiting toxicity (DLT) was defined as any Grade 3 or higher acute toxicities causing continuous interruption of radiation for over 1 week. Results: From April 2012 to February 2014, dose has been escalated up to LEVEL 4 (70 Gy). All of the 25 patients finished the prescribed dose without DLT, and 10 of them developed Grade 3 acute esophagitis. One patient of LEVEL 2 died of esophageal hemorrhage within 1 month after completion of radiotherapy, which was not definitely correlated with treatment yet. Late toxicities remained under observation. With median follow up of 8.9 months, one-year overall survival and local control was 69.2% and 77.4%, respectively. Conclusions: Dose escalation in esophageal cancer based on 18 FDG-PET/CT has been safely achieved up to 70 Gy using the SIB technique. Acute toxicities were well tolerated, whereas late toxicities and long-term outcomes deserved further observation

Primary processes in radiation chemistry. LET (Linear Energy Transfer) effect in water radiolysis

International Nuclear Information System (INIS)

Trupin-Wasselin, V.

2000-01-01

The effect of ionizing radiations on aqueous solutions leads to water ionization and then to the formation of radical species and molecular products (e - aq , H . , OH . , H 2 O 2 , H 2 ). It has been shown that the stopping power, characterized by the LET value (Linear Energy Transfer) becomes different when the nature of the ionizing radiations is different. Few data are nowadays available for high LET radiations such as protons and high energy heavy ions. These particles have been used to better understand the primary processes in radiation chemistry. The yield of a chemical dosimeter (the Fricke dosimeter) and those of the hydrogen peroxide have been determined for different LET. The effect of the dose rate on the Fricke dosimeter yield and on the H 2 O 2 yield has been studied too. When the dose rate increases, an increase of the molecular products yield is observed. At very high dose rate, this yield decreases on account of the attack of the molecular products by radicals. The H 2 O 2 yield in alkaline medium decreases when the pH reaches 12. This decrease can be explained by a slowing down of the H 2 O 2 formation velocity in alkaline medium. Superoxide radical has also been studied in this work. A new detection method: the time-resolved chemiluminescence has been perfected for this radical. This technique is more sensitive than the absorption spectroscopy. Experiments with heavy ions have allowed to determine the O 2 .- yield directly in the irradiation cell. The experimental results have been compared with those obtained with a Monte Carlo simulation code. (O.M.)

Radiation protection limits and review procedure

International Nuclear Information System (INIS)

Dafauti, Sunita; Gopalakrishnan, R.K.; Pradeepkumar, K.S.

2017-01-01

The primary means of controlling radiation exposure in planned exposure situations in nuclear facilities/radiological laboratories are by good design of facilities, equipment, operating procedures and by ensuring appropriate training to all plant occupational workers. In planned exposure situations, exposure at some level can be expected to occur. For planned exposure situations, exposures are subject to control for ensuring that the specified dose limits for occupational exposure and those for public exposure are not exceeded and optimization is applied to attain the desired level of protection and safety. The person or organization responsible for any facility or activity that gives rise to radiation exposure should have the prime responsibility for protection and safety, which cannot be delegated

Importance of contouring the cervical spine levels in initial intensity-modulated radiation therapy radiation for head and neck cancers: Implications for re-irradiation

Directory of Open Access Journals (Sweden)

Parashar Bhupesh

2009-01-01

Full Text Available Aim: To evaluate the maximum differential cervical spinal (C-spine cord dose in intensity-modulated radiation therapy (IMRT plans of patients undergoing radiotherapy for treatment of head and neck cancer. Materials and Methods: The C-spine of ten head and neck cancer patients that were planned using IMRT and each cervical vertebral body and the right and left sides was contoured by splitting the cord in the center. Dose-volume histograms (DVH and maximum point doses were obtained for each contour and compared. Results: The dose to the cord varied with the location of the primary tumor but such variation was not consistently seen. This report provides information that is critical for planning reirradiation treatments. We recommend that contouring of the C-spine cord with IMRT should include outlining of each cervical cord level and identification of the right and the left sides of the cord on each plan.

Radiation studies on the microflora in a High-level radiation environment

International Nuclear Information System (INIS)

Zahiera, T.S.

1988-01-01

Radiation sensitivities of microflora in the air environment of the irradiation room of the 60 CO industrial irradiation facility of NCRRT was studied. The isolated microflora was identified to be the Gram positive micrococci, and the gram positive bacilli: coagulans and laterosporous. The study of the dose-survival counts dependence of the colonies showed the existance of the combination of at least two groups of micro-organisms with different sensitivities to radiation. The value of the radiation resistant group was found to be 2.2 10kGy. A method is presented to estimate the amount of each group in the initial culture. A study of the dependence of radiation lethality on the dose rate of radiation on the aerobic dry microbes showed no significant effect in the dose-rate range from 330 down to 44 Gy.min

The Australasian radiation protection society's position statement on risks fro low levels of ionizing radiation

International Nuclear Information System (INIS)

Higson, D.J.

2006-01-01

Full text: Controversy continues in the radiation protection literature on whether or not ionizing radiation is harmful at low doses, with unresolved scientific uncertainty about effects below a few tens of millisieverts. To settle what regulatory controls (if any) should apply in this dose region, an assumption has to be made relating dose to the possibility of harm or benefit. The assumption made and the way it is applied can have far-reaching effects, not only on the scale of regulatory compliance required but also on public perception of risk, and therefore on the technological choices made by society. It is important therefore that decisions reached concerning the regulation of low doses of ionizing radiation derive from rational arguments and are perceived to have an ethical basis. It is also important that such decisions are neither portrayed nor perceived as resolving the scientific uncertainties: rather, they serve merely to facilitate the implementation of appropriate measures to ensure safety. At its Annual General Meeting in 2004, the Australasian Radiation Protection Society (ARPS) set up a working group to draft a statement of the Society's position on this matter. The resulting position statement was adopted by the Society at its Annual General Meeting on 14 November 2005. Its salient features are as follows: There is insufficient evidence to establish a dose-effect relationship for doses that are less than a few tens of millisieverts in a year. A linear extrapolation from higher dose levels should be assumed only for the purpose of applying regulatory controls; Estimates of collective dose arising from individual doses that are less than some tens of millisieverts in a year should not be used to predict numbers of fatal cancers; The risk to an individual of doses significantly less than 100 microsieverts in a year is so small, if it exists at all, that regulatory requirements to control exposure at this level are not warranted. The paper will

Low level radiation: how does the linear without threshold model provide the safety of Canadian

International Nuclear Information System (INIS)

Anon.

2010-01-01

The linear without threshold model is a model of risk used worldwide by the most of health organisms of nuclear regulation in order to establish dose limits for workers and public. It is in the heart of the approach adopted by the Canadian commission of nuclear safety (C.C.S.N.) in matter of radiation protection. The linear without threshold model presumes reasonably it exists a direct link between radiation exposure and cancer rate. It does not exist scientific evidence that chronicle exposure to radiation doses under 100 milli sievert (mSv) leads harmful effects on health. Several scientific reports highlighted scientific evidences that seem indicate a low level of radiation is less harmful than the linear without threshold predicts. As the linear without threshold model presumes that any radiation exposure brings risks, the ALARA principle obliges the licensees to get the radiation exposure at the lowest reasonably achievable level, social and economical factors taken into account. ALARA principle constitutes a basic principle in the C.C.S.N. approach in matter of radiation protection; On the radiation protection plan, C.C.S.N. gets a careful approach that allows to provide health and safety of Canadian people and the protection of their environment. (N.C.)

Radiation levels in Ecuadorian Cattle Milk

International Nuclear Information System (INIS)

Reinoso, Teresa; Vasquez, Ramiro

2008-01-01

Full text: The radiation and natural radioactivity present in the ground from a radioactive decay of 238 U, 235 U and 232 Th, and of the radioisotope 40 K can be transferred to the nutritional chain of the human being. Milk is a food considered basic within population's diet. The Ecuadorian Highlands has the greater production of cattle milk in the country, this industry needs great extensions of graze and available superficial water, which the cows consumed for crude milk production, with the consequent product industrialization. In the present research, gamma radiation levels where monitoring in 12 crude milk representative samples of the zone. The measurements where carried out using an equipment of spectrometry gamma ray system, with a detector of Hiperpuro Germanium (GeHp), which has been used in the analysis of standard and samples spectrums, with a constant geometry of the sample holder. The spectrums of the milk analysis show the presence of the radioisotopes coming from uranium radioactive decay. The majority of the values of activity concentration are below the minimum detection activity, unlike the potassium that presents a detectable but a non quantitative spectrum. So far, with the results obtained it is possible to guarantee the milk consumption and its derivatives in the Andean Region of the country. Related research will allow us implementing the radiological monitoring of this and other foods in the country, in order to protected population health. (author)

Dose limits, constraints, reference levels. What does it mean for radiation protection?

International Nuclear Information System (INIS)

Breckow, J.

2016-01-01

The established concept of radiation protection with its basic principles justification, optimization, and limitation has proved its value and is going to be continued. In its deeper meaning, however, the concept is rather subtle and complex. Furthermore, in some aspects there remain some breaches or inconsistencies. This is just true for the terms dose limit, reference lever, and constraint that are tightly associated with the radiation protection principles. In order to guarantee the ability of radiation protection in whole extent, the subtle differences of meaning have to be communicated. There is a permanent need to defend the conceptual function of these terms against deliberate or undeliberate misinterpretations. Reference levels are definitely not the same as dose limits and they may not be misused as such. Any attempt to misinterpret fundamental radiation protection principles for selfish purposes should discouraged vigorously.

Measurements of the ionising radiation level at a nuclear medicine facility performing PET/CT examinations

International Nuclear Information System (INIS)

Tulik, P.; Kowalska, M.; Golnik, N.; Budzynska, A.; Dziuk, M.

2017-01-01

This paper presents the results of radiation level measurements at workplaces in a nuclear medicine facility performing PET/ CT examinations. This study meticulously determines the staff radiation exposure in a PET/CT facility by tracking the path of patient movement. The measurements of the instantaneous radiation exposure were performed using an electronic radiometer with a proportional counter that was equipped with the option of recording the results on line. The measurements allowed for visualisation of the staff's instantaneous exposure caused by a patient walking through the department after the administration of "1"8F-FDG. An estimation of low doses associated with each working step and the exposure during a routine day in the department was possible. The measurements were completed by determining the average radiation level using highly sensitive thermoluminescent detectors. (authors)

Risk estimation and decision making: the health effects on populations of exposure to low levels of ionizing radiation

International Nuclear Information System (INIS)

Fabrikant, J.I.

1982-01-01

Presented is a background for an understanding of the potential health effects in populations exposed to low-level radiation. Discussed is the knowledge about the health effects of low-level radiation. Comments on how the risks of radiation-induced cancer and genetically-related ill-health in man may be estimated, the sources of the scientific and epidemiological data, the dose-response models used, and the uncertainties which limit precise estimates of excess risks from radiation. Also discussed are the implications of numerical risk estimation for radiation protection and decision-making for public health policy

Radiation doses in alternative commercial high-level waste management systems

International Nuclear Information System (INIS)

Schneider, K.J.; Pelto, P.J.; Lavender, J.C.; Daling, P.M.; Fecht, B.A.

1986-01-01

In the commercial high-level waste management system, potential changes are being considered that will augment the benefits of an integral monitored retrievable storage (MRS) facility. The US Department of Energy (DOE) has recognized that alternative options could be implemented in the authorized waste management system (i.e., without an integral MRS facility) to potentially achieve some of the same beneficial effects of the integral MRS system. This paper summarizes those DOE-sponsored analyses related to radiation doses resulting from changes in the waste management system. This report presents generic analyses of aggregated radiation dose impacts to the public and occupational workers, of nine postulated changes in the operation of a spent-fuel management system without an MRS facility

Design considerations of fission and corrosion product in primary system of MONJU

International Nuclear Information System (INIS)

Yanagisawa, T.; Akagane, K.; Yamamoto, K.; Kawashima, K.

1976-01-01

General influence of fission and corrosion products in primary system on MONJU plant design is reviewed. Various research and development works are now in progress to decrease the generation rate, to remove the products more effectively and to develop the methods of evaluation the behaviour of radioactive products. The inventory and distribution of fission and corrosion products in the primary circuit of MONJU are given. The radiation levels on the primary components are estimated to be several roentgens per hour. (author)

Radiation emitter-detector package

International Nuclear Information System (INIS)

O'Brien, J.T.; Limm, A.C.; Nyul, P.; Tassia, V.S. Jr.

1978-01-01

Mounted on the metallic base of a radiation emitter-detector is a mounting block is a first projection, and a second projection. A radiation detector is on the first projection and a semiconductor electroluminescent device, i.e., a radiation emitter, is on the second projection such that the plane of the recombination region of the electroluminescent device is perpendicular to the radiation incident surface of the radiation detector. The electroluminescent device has a primary emission and a secondary emission in a direction different from the primary emission. A radiation emitter-detector package as described is ideally suited to those applications wherein the secondary radiation of the electroluminescent device is fed into a feedback circuit regulating the biasing current of the electroluminescent device

Dose response curves for effects of low-level radiation

International Nuclear Information System (INIS)

Myers, D.K.

1980-01-01

The linear dose-response model used by international committees to assess the genetic and carcinogenic hazards of low-level radiation appears to be the most reasonable interpretation of the available scientific data that are relevant to this topic. There are, of course, reasons to believe that this model may overestimate radiation hazards in certain instances, a fact acknowledged in recent reports of these committees. The linear model is now also being utilized to estimate the potential carcinogenic hazards of other agents such as asbestos and polycyclic aromatic hydrocarbons. This model implies that there is no safe dose for any of these agents and that potential health hazards will increase in direct proportion to total accumulated dose. The practical implication is the recommendation that all exposures should be kept 'as low as reasonably achievable, economic and social factors being taken into account'. (auth)

Investigation of environmental natural penetrating radiation level in inner mongolia

International Nuclear Information System (INIS)

Li Wenyuan; Du Xuelin; Zhang Baozhong; Fu Su; Chen Jun; Zhang Wenhai

1990-01-01

The scheme, quality assurance measure, and results for environmental natural penetrating radiation level investigation in Inner Mongolia Autonomous Region was reported. Over the whole Region area of more than 1.18 million km 2 , 1018 net grid measuring points were selected with grid spacing of 25 x 25 km. The range of natural environmental terrestrial γ-radiation air absorbed dose rate over fields was (0.96-18.62) x 10 -8 Gy·h -1 , the range of γ-radiatoin dose rate over road was (1.07-26.08) x 10 -8 Gy·h -1 , the mean was 5.92 x 10 -8 Gy·h -1 ; the range of γ-radiation dose rate in buildings was (3.82-18.94) x 10 -8 Gy·h -1 ; the range of outdoor air absorbed dose rate caused by ionization compnents of cosmic rays was (3.12-5.55) x 10 -8 Gy·h -1 , while indoor range was (2.60-4.66) x 10 -8 Gy·h -1 ; the range of outdoor natural penetrating radiation dose rate was (8.31-11.26) x 10 -8 Gy·h -1 , indoor range was (11.20-14.67) x 10 -8 Gy·h -1 ; annual average individual effective dose equivalent and annual collective effective dose equivalent caused by natural penetrating radiatoin were 0.84 mSv and 1.61 x 10 4 man·Sv respectively. The georgaphical distribution of terrestrial γ-radiation dose rate within all region was reprted, the increase of environmental terrestial γ-radiation caused by human activity was also pointed. This ought to be paid enough attention to

Verification test for radiation reduction effect and material integrity on PWR primary system by zinc injection

Energy Technology Data Exchange (ETDEWEB)

Kawakami, H.; Nagata, T.; Yamada, M. [Nuclear Power Engineering Corp. (Japan); Kasahara, K.; Tsuruta, T.; Nishimura, T. [Mitsubishi Heavy Industries, Ltd. (Japan); Ishigure, K. [Saitama Inst. of Tech. (Japan)

2002-07-01

Zinc injection is known to be an effective method for the reduction of radiation source in the primary water system of a PWR. There is a need to verify the effect of Zn injection operation on radiation source reduction and materials integrity of PWR primary circuit. In order to confirm the effectiveness of Zn injection, verification test as a national program sponsored by Ministry of Economy, Trade and Industry (METI) was started in 1995 for 7-year program, and will be finished by the end of March in 2002. This program consists of irradiation test and material integrity test. Irradiation test as an In-Pile-Test managed by AEAT Plc(UK) was performed using the LVR-15 reactor of NRI Rez in Check Republic. Furthermore, Out-of-Pile-Test using film adding unit was also performed to obtain supplemental data for In-Pile-Test at Takasago Engineering Laboratory of NUPEC. Material Integrity test was planned to perform constant load test, constant strain test and corrosion test at the same time using large scale Loop and slow strain extension rate testing (SSRT) at Takasago Engineering Laboratory of NUPEC. In this paper, the results of the verification test for Zinc program at present are discussed. (authors)

Primary management of esophageal carcinoma with radiation therapy and surgery and correlation of failure pattern based on autopsy findings

International Nuclear Information System (INIS)

Ali, M.M.; Goertz, S.R.

1989-01-01

This paper reports a study of forty-seven patients with esophageal carcinoma who were treated definitively with radiation therapy (n = 18) and radical surgery (n = 18) or received palliative treatment (n = 11) at the Medical College of Virginia between 1967 and 1982. The average intervals between diagnosis and death were 5, 7, and 4 months, respectively. Autopsy revealed that 80% with radiation therapy and 50% in the surgery group had persistent local-regional disease. Eleven of 36 had adrenal metastasis and eight of 36 had a second primary in the head, neck, lung or prostate. The data show a significant incidence of persistent disease in spite of negative surgical margins. Additional treatment with chemotherapy or postoperative radiation therapy should be considered

Aspects of research on effects of population exposed to low level radiation in China

International Nuclear Information System (INIS)

Wei, L.

1992-01-01

Research works of epidemiology and experimental biology concerning health effects on populations exposed to low level ionizing radiation in China have been reviewed, with emphasis on the studies of mortality of malignancies and prevalence of hereditary diseases in a high background radiation area (HBRA) (radiation level is about three times of the control area of normal background CA), where the inhabitant families have lived for many generations. About one million person-years in HBRA and as many in CA were observed for cancer mortality. Statistical analysis showed that no difference was found either in mortality of all cancers or leukemias between HBRA and CA. The incidence of Down Syndrome in HBRA was within the range of spontaneous incidence and dependent on age of maternity. The characteristics of adaptive response induced by low level irradiation in humans as well as in experimental animal lymphocytes observed in Chinese laboratories are also discussed in this presentation

[Blood serum level of primary bile acids in cattle, horses, swine and dogs].

Science.gov (United States)

Karsai, F; Szaniszló, F; Pethes, G

1991-02-01

The levels of the two primary bile acids, cholic acid (CA) and chenodeoxycholic acid (CDCA), were determined by radioimmunoassay in cattle, horse, pig and dog serum. The mean serum cholic acid (SCA) and deoxycholic acid (SCDCA) levels of cows varied with their reproductive status, being 7.8 (+/- 3.3) and 1.5 (+/- 1.0) mumol/l in dry cows, 17.8 (+/- 6.9) and 2.3 (+/- 1.0) mumol/l in freshly calved dams, and 15.8 (+/- 5.7) and 2.3 (+/- 0.8) mumol/l, respectively, in lactating cows. The SCA level found in the immediate prepartal period and also on the day of calving corresponded to those found during the dry period, then, they tended to rise 2 days after calving and attained the peak characteristic for freshly calved dams on day 3 or 4 post partum. Feed consumption had no influence on the serum levels of primary bile acids, and circadian variations of SCA and SCDCA were also negligible. Suckling calves had much lower SCA levels (2.3 (+/- 1.0) mumol/l before feeding than cows. This initial concentration rose to 10.3 (+/- 2.9) mumol/l 1 h after feeding and returned to 5.0 (+/- 2.1) mumol/l 3 h later. Like cows, horses showed no appreciate difference between pre- and post-feeding levels of SCA (2.2 (+/- 1.2) mumol/l) and SCDCA (1.1 (+/- 0.3) mumol/l). Unlike bovines, pigs and dogs showed a considerable increase in the serum levels of the primary bile acids after feeding.(ABSTRACT TRUNCATED AT 250 WORDS)

Radiation in complex exposure situations. Assessing health risks at low levels from concomitant exposures to radiation and chemicals

International Nuclear Information System (INIS)

Hornhardt, S.; Jung, T.; Burkart, W.

2000-01-01

Health effects from exposures to ionizing radiation are in general the result of complex multi-step reaction chains involving changes and responses on the level of molecules, cells, tissues and organisms. In environmental low dose exposure situations ionizing radiation only contributes a small fraction to the life-long attack on DNA by other exogenous and endogenous genotoxins. Nevertheless, efforts to assess and quantify deleterious effects at low exposure levels are directed mainly towards radiation as a single isolated agent, and rarely towards the concomitant presence of other natural and anthropogenic toxicants. Only these combined exposures may lead to observable health risk effects. In addition they might differ from those expected from simple addition of the individual risks due to interaction. The existing data base on combined effects is rudimentary, mainly descriptive and rarely covers exposure ranges large enough to make direct inferences to present day low dose exposure situations. Therefore, any risk assessment will have to consider the question whether combined effects, i.e. interaction between two or more agents will influence the health outcome from specific exposure situations in such a way that predictions derived from simple standard exposure situations would have to be revised. In view of the multitude of possible interactions between the large number of potentially harmful agents in the human environment, descriptive approaches will have to be supplemented by the use of mechanistic models for critical health endpoints such as cancer. Agents will have to be grouped depending on their physical or chemical mode of action at the molecular and cellular level, to generalize and predict the outcome of combined exposures at low exposure levels and the possibility of interactions. (author)

Legal recourse for damages suffered from low-level radiation exposure

International Nuclear Information System (INIS)

Pesto-Edwards, M.M.

1984-01-01

In the past few years several events involving toxic substances have received widespread coverage by the media, thereby altering an already aware population to the hazards of exposure to toxic agents. Incidents such as Three Mile Islane, Love Canal, and Hemlock, Michigan, the exposure plight of veterans to radiation at the Nevada Test Site and to Agent Orange in Vietnam, and to the exposure of factory workers to asbestos, have been highly publicized. In part because of this publicity, the emphasis of the 1970's on controlling water and air pollution has been shifting slowly during the 1980s to the of control of hazardous waste pollution. Despite this shifting emphasis, legislative and judicial systems have been slow to respond. Few remedies are available to real and imagined victims of toxic substances. From a legal point of view, there is little difference between exposure to low levels of radiation and low levels of toxic chemicals. Both instances fall under the broader domain of environmental law. Depending on the circumstances, one instance might provide legal precedent for the other. This chapter presents examples drawn from both areas in order to illustrate current issues. The discussion is divided into four parts: (1) the common law tort theories that may be asserted when a plaintiff has suffered injury resulting from exposure to low-level radiation or other toxic substances; (2) the difficulties posed by the relief mechanisms rooted in traditional common law; (3) current federal legislation, along with its merits and shortcomings; and (4) solutions to the obstacles now faced by plaintiffs in attempting to recover their damages. Also discussed are suggested judicial and legislative solutions designed to remedy the damages caused to persons exposed to toxic wastes

Genetic damage from low-level and natural background radiation

International Nuclear Information System (INIS)

Oftedal, P.

1988-01-01

Relevant predictions that have been made of possible low level biological effects on man are reviewed, and the estimate of genetic damage is discussed. It is concluded that in spite of a number of attempts, no clear-cut case of effects in human populations of radiation at natural levels has been demonstrated. The stability of genetic material is dynamic, with damage, repair and selection running as continuous processes. Genetic materials are well protected and are conservative in the extreme, not least because evolution by genetic adaptation is an expensive process: Substitution of one allele A 1 by another A 2 means the death of the whole A 1 population

Does exposure to very high levels of natural radiation induce hematological alterations in humans?

International Nuclear Information System (INIS)

Ghiassi-Nejad, M.

2003-01-01

Full text: It has long been known that total body exposure to moderate doses decrease the number of circulating erythrocytes, platelets, granulocytes, and lymphocytes. However, data on hematopoietic effects of exposure to very low doses of ionizing radiation in humans are scarce. Recently it has been reported that hematological parameters have significant positive associations with the radiation dose received by residents lived near a nuclear power plant. Ramsar, a city in northern Iran, has some inhabited areas with the highest levels of natural radiation studied so far. A population of about 2000 is exposed to average annual radiation levels of 10.2 mGy y -1 and the highest recorded external gamma dose rates are about 130 mGy y -1 . In this study, hematological parameters such as counts of leukocytes, lymphocytes, monocytes, granulocytes, red blood cells, hemoglobin, hematocrit, MCV, MCH, MCHC, RDW, PLT, and MPV were measured in the inhabitants. The results of this study indicated that there was no any statistically significant alteration in hematological parameters of the inhabitants of very high background radiation areas of Ramsar compared to those of a neighboring control area

In vitro transformation of primary cultures of neonatal BALB/c mouse epidermal cells with ultraviolet-B radiation

International Nuclear Information System (INIS)

Ananthaswamy, H.N.; Kripke, M.L.

1981-01-01

Primary epidermal cultures from neonatal BALB/c mice were used to study the carcinogenic effects of ultraviolet radiation in vitro. These cultures were irradiated once through a Falcon plastic dish cover with an FS40 sunlamp [ultraviolet B, lambda approximately 290 to 400 nm] for various lengths of time and maintained for 8 to 12 weeks without subculturing. During this period, most of the cells in the untreated control showed signs of morphological differentiation and eventually died. The cultures irradiated with ultraviolet B radiation also behaved in the same manner except that, in some dishes, small populations of surviving cells began to proliferate and developed into morphologically distinct foci. Seven long-term cell lines were derived from these ultraviolet-irradiated primary epidermal cell cultures. Six of these cell lines produced tumors when injected s.c. into normal and/or immunosuppressed syngeneic recipients. These tumorigenic cell lines lacked definitive characteristics of differentiated epidermal cells, but the cells possessed intermediate junctions, suggesting that they were of epithelial origin. Some of these in vitro-transformed cell lines appeared to be highly antigenic inasmuch as they grew preferentially in immunosuppressed BALB/c mice as compared to their growth in normal syngeneic recipients

English Vocabulary Acquisition of Bilingual Learners at the Primary and Secondary Levels

Science.gov (United States)

Pholsward, Ruja; Boonprasitt, Donrutai

2015-01-01

This paper reports research findings of English vocabulary acquisition of bilingual learners at the levels of Primary 6 and Secondary 3 at Satit Bilingual School of Rangsit University. The purpose was to find out the extent to which learners at these levels have acquired English vocabulary to communicate their ideas about themselves and their…

Antibody Level Upon Newcastle Disease Virus In Chicken After Exposure To GAMMA Radiation

International Nuclear Information System (INIS)

Pejakovic-Hlede, J.; Dotur, J.; Pasic, S.; Gottstein, Z.; Majer, M.; Vilic, M.

2015-01-01

The aim of this study was to investigate the effect of gamma radiation upon Newcastle disease virus antibody level after acute exposure with dose of 0.05 Gy and 0.8 Gy gamma radiation. The experiment was made on light chicken breeds irradiated with dose of 0.05 Gy and 0.8 Gy gamma radiation with dose rate of 0.0117 Gy/s on the first and on the third day after hatching. Chicken were vaccinated by nebulization on the first day after hatching. Antibody level upon Newcastle disease in blood serum of chicken was quantified by hemagglutination inhibition assay on 1th, 7th, 14th and 28th day after vaccination. Results demonstrate that antibody titre against Newcastle disease in blood serum of chicken irradiated with dose of 0.05 Gy and 0.8 Gy gamma radiation on the first and on the third day after hatching was not statistically significant. Therefore, these results suggest that irradiation of light chicken breeds on the first and third day after vaccination with dose of 0.05 Gy and 0.8 Gy does not change antibody titre upon Newcastle disease. (author).

Radiofrequency radiation from nearby base stations gives high levels in an apartment in Stockholm, Sweden: A case report

Science.gov (United States)

Hardell, Lennart; Carlberg, Michael; Hedendahl, Lena K.

2018-01-01

Exposure to radiofrequency (RF) radiation was classified in 2011 as a possible human carcinogen, Group 2B, by the International Agency for Research on Cancer of the World Health Organisation. Evidence of the risk of cancer risk has since strengthened. Exposure is changing due to the rapid development of technology resulting in increased ambient radiation. RF radiation of sufficient intensity heats tissues, but the energy is insufficient to cause ionization, hence it is called non-ionizing radiation. These non-thermal exposure levels have resulted in biological effects in humans, animals and cells, including an increased cancer risk. In the present study, the levels of RF radiation were measured in an apartment close to two groups of mobile phone base stations on the roof. A total of 74,531 measurements were made corresponding to ~83 h of recording. The total mean RF radiation level was 3,811 µW/m2 (range 15.2–112,318 µW/m2) for the measurement of the whole apartment, including balconies. Particularly high levels were measured on three balconies and 3 of 4 bedrooms. The total mean RF radiation level decreased by 98% when the measured down-links from the base stations for 2, 3 and 4 G were disregarded. The results are discussed in relation to the detrimental health effects of non-thermal RF radiation. Due to the current high RF radiation, the apartment is not suitable for long-term living, particularly for children who may be more sensitive than adults. For a definitive conclusion regarding the effect of RF radiation from nearby base stations, one option would be to turn them off and repeat the measurements. However, the simplest and safest solution would be to turn them off and dismantle them. PMID:29725476

Radiofrequency radiation from nearby base stations gives high levels in an apartment in Stockholm, Sweden: A case report.

Science.gov (United States)

Hardell, Lennart; Carlberg, Michael; Hedendahl, Lena K

2018-05-01

Exposure to radiofrequency (RF) radiation was classified in 2011 as a possible human carcinogen, Group 2B, by the International Agency for Research on Cancer of the World Health Organisation. Evidence of the risk of cancer risk has since strengthened. Exposure is changing due to the rapid development of technology resulting in increased ambient radiation. RF radiation of sufficient intensity heats tissues, but the energy is insufficient to cause ionization, hence it is called non-ionizing radiation. These non-thermal exposure levels have resulted in biological effects in humans, animals and cells, including an increased cancer risk. In the present study, the levels of RF radiation were measured in an apartment close to two groups of mobile phone base stations on the roof. A total of 74,531 measurements were made corresponding to ~83 h of recording. The total mean RF radiation level was 3,811 µW/m 2 (range 15.2-112,318 µW/m 2 ) for the measurement of the whole apartment, including balconies. Particularly high levels were measured on three balconies and 3 of 4 bedrooms. The total mean RF radiation level decreased by 98% when the measured down-links from the base stations for 2, 3 and 4 G were disregarded. The results are discussed in relation to the detrimental health effects of non-thermal RF radiation. Due to the current high RF radiation, the apartment is not suitable for long-term living, particularly for children who may be more sensitive than adults. For a definitive conclusion regarding the effect of RF radiation from nearby base stations, one option would be to turn them off and repeat the measurements. However, the simplest and safest solution would be to turn them off and dismantle them.

Cytogenetic and hematological studies in the workers occupationally exposed to low levels of ionizing radiation

International Nuclear Information System (INIS)

Zakeri, F.; Honarjoo, M.; Rajab pour, M.; Zahadat, A.; Ahmad pour, M.J.; Asghari, K.

2007-01-01

Complete text of publication follows. Objective: This study was aimed at detecting both the incidence of chromosomal aberrations and changes in the hematological parameters as biomarkers of possible radiation injury among workers occupationally exposed to low levels of ionizing radiation and detecting the dose-effect relationship. Methods: Samples of peripheral blood were collected from 38 male industrial radiographers exposed to ionizing radiation for 1-16 years and from 24 age- and sex-matched healthy blood donors without radiation history served as control group. All radiation workers were routinely monitored with film badge. Cytogenetic analysis in peripheral blood lymphocytes assessed by the conventional chromosome aberration assay and at least 200 metaphases for each person were scored. The collected blood samples were analyzed for hematological assay using an automatic analyzer Sysmex KX-21, where 14 different parameters were computerized. Mann-Whitney U test was used to compare the frequencies of the unstable aberrations and hematological parameters between test and control groups. Dose-effect relationship and the influence of age and duration of employment was tested by regression analysis. Results and conclusion: The mean frequencies of dicentric and acentric chromosome aberrations were significantly higher in the exposed group than in the control group (P< 0.0005). No correlation between chromosomal aberrations and physical dose and age was observed in the exposed group. Also there is no clear relation between chromosome damage and duration of exposure. However, the increase in chromosome aberrations in the exposed group was not followed by a corresponding hematological depression. The average values of hematological indices were within the reference levels and did not show any significant differences with control group. A tendency of decreasing the absolute lymphocyte count within the referential levels was the only hematological effect in radiation

Radiation protection calibration facilities at the National Radiation Laboratory, New Zealand

International Nuclear Information System (INIS)

Foote, B.J.

1995-01-01

The National Radiation Laboratory (NRL), serving under the Ministry of Health, provides radiation protection services to the whole of New Zealand. Consequently it performs many functions that are otherwise spread amongst several organizations in larger countries. It is the national regulatory body for radiation protection. It writes and enforces codes of safe practice, and conducts safety inspections of all workplaces using radiation. It provides a personal monitoring service for radiation workers. It also maintains the national primary standards for x-ray exposure and 60 Co air kerma. These standards are transferred to hospitals through a calibration service. The purpose of this report is to outline the primary standards facilities at NRL, and to discuss the calibration of dosemeters using these facilities. (J.P.N.)

System-Level Model for OFDM WiMAX Transceiver in Radiation Environment

International Nuclear Information System (INIS)

Abdel Alim, O.; Elboghdadly, N.; Ashour, M.M.; Elaskary, A.M.

2008-01-01

WiMAX (Worldwide Inter operability for Microwave Access), an evolving standard for point-to-multipoint wireless networking, works for the l ast mile c onnections for replacing optical fiber technology network but with no need for adding more infra structure within crowded areas. Optical fiber technology is seriously considered for communication and monitoring applications in space and around nuclear reactors. Space and nuclear environments are characterized, in particular, by the presence of ionizing radiation fields. Therefore the influence of radiation on such networks needs to be investigated. This paper has the objective of building a System level model for a WiMAX OFDM (Orthogonal Frequency Division Multiplexing) based transceiver. Modeling irradiation noise as an external effect added to the Additive White Gaussian noise (AWGN). Then analyze, discuss the results based on qualitatively performance evaluation using BER calculations for radiation environment

Radiation and health: low-level-ionizing radiation exposure and effects

International Nuclear Information System (INIS)

Kant, Krishan

2013-01-01

In the present paper, brief review of the available literature, data and reports of various radiation exposure and protection studies is presented. An in-depth analysis of reports available suggests that the possible beneficial outcomes of exposure to LLIR are: increased Growth rate, Development, Neurogenesis, Memory, Fecundity (Fertility), Immunity (Resistance to diseases due to large doses of radiation) and Lifespan (Longevity) Decreased Cancer deaths, Cardiovascular deaths, Respiratory deaths, Neonatal deaths, Sterility, Infection, Premature deaths. The findings also suggest that the LNT theory is overly stated for assessing carcinogenic risks at low doses. It is not scientifically justified and should be banned as it creates radio phobia thereby blocking the efforts to supply reliable, environmentally friendly nuclear energy and important medical therapies. There is no need for anyone to live in fear of serious health consequences from the radioactivity that comes out from nuclear installations and exposures in the range of background radiation. A linear quadratic model has been given illustrating the validity of radiation hormesis, besides the comparison of the dose rates arising from natural and manmade sources to Indian population

MO-C-18C-01: Radiation Risks at Level of Few CT Scans: How Real?- Science to Practice

International Nuclear Information System (INIS)

Rehani, M; Samei, E; Morgan, W; Goske, M; Shore, R

2014-01-01

There are controversies surrounding radiation effects in human population in the range of radiation doses encountered by patients resulting from one to several CT scans. While it is understandable why the effects from low levels of diagnostic radiation are controversial, the situation is complicated by the media which may distort the known facts. There is need to understand the state of science regarding low-level radiation effects and also to understand how to communicate the potential risk with patients, the public and media. This session will seek to come to a consensus in order to speak with one voice to the media and the public. This session will review radiation effects known so far from a variety of exposed groups since the nuclear holocaust, provide clarification where effects are certain and where they are not, at what level extrapolation is the only way and at what level there is weak but agreeable acceptance. We will depict where and why there is agreement among organizations responsible for studying radiation effects, and how to deal with situations where effects are uncertain. Specific focus on radiation effects in children will be provided.Finally, the session will attempt to bridge the communication gap from the science to how to be an effective communicator with patients, parents, and media about ionizing radiation. Learning Objectives: To have a clear understanding about certainties and uncertainties of radiation effects at the level of a few CT scans To understand the results and limitations from 3 major pediatric CT scientific studies on childhood exposures published recently. To understand successful strategies used in risk communication

MO-C-18C-01: Radiation Risks at Level of Few CT Scans: How Real?- Science to Practice

Energy Technology Data Exchange (ETDEWEB)

Rehani, M [International Atomic Energy Agency, Vienna (Austria); Samei, E [Duke University Medical Center, Durham, NC (United States); Morgan, W [Pacific Northwest National Laboratory, Richland, WA (United States); Goske, M [Cincinnati Childrens Hospital, Cincinnati, OH (United States); Shore, R

2014-06-15

There are controversies surrounding radiation effects in human population in the range of radiation doses encountered by patients resulting from one to several CT scans. While it is understandable why the effects from low levels of diagnostic radiation are controversial, the situation is complicated by the media which may distort the known facts. There is need to understand the state of science regarding low-level radiation effects and also to understand how to communicate the potential risk with patients, the public and media. This session will seek to come to a consensus in order to speak with one voice to the media and the public. This session will review radiation effects known so far from a variety of exposed groups since the nuclear holocaust, provide clarification where effects are certain and where they are not, at what level extrapolation is the only way and at what level there is weak but agreeable acceptance. We will depict where and why there is agreement among organizations responsible for studying radiation effects, and how to deal with situations where effects are uncertain. Specific focus on radiation effects in children will be provided.Finally, the session will attempt to bridge the communication gap from the science to how to be an effective communicator with patients, parents, and media about ionizing radiation. Learning Objectives: To have a clear understanding about certainties and uncertainties of radiation effects at the level of a few CT scans To understand the results and limitations from 3 major pediatric CT scientific studies on childhood exposures published recently. To understand successful strategies used in risk communication.

Primary radiation damage characterization of α-iron under irradiation temperature for various PKA energies

Science.gov (United States)

Sahi, Qurat-ul-ain; Kim, Yong-Soo

2018-04-01

The understanding of radiation-induced microstructural defects in body-centered cubic (BCC) iron is of major interest to those using advanced steel under extreme conditions in nuclear reactors. In this study, molecular dynamics (MD) simulations were implemented to examine the primary radiation damage in BCC iron with displacement cascades of energy 1, 5, 10, 20, and 30 keV at temperatures ranging from 100 to 1000 K. Statistical analysis of eight MD simulations of collision cascades were carried out along each [110], [112], [111] and a high index [135] direction and the temperature dependence of the surviving number of point defects and the in-cascade clustering of vacancies and interstitials were studied. The peak time and the corresponding number of defects increase with increasing irradiation temperature and primary knock-on atom (PKA) energy. However, the final number of surviving point defects decreases with increasing lattice temperature. This is associated with the increase of thermal spike at high PKA energy and its long timespan at higher temperatures. Defect production efficiency (i.e., surviving MD defects, per Norgett-Robinson-Torrens displacements) also showed a continuous decrease with the increasing irradiation temperature and PKA energy. The number of interstitial clusters increases with both irradiation temperature and PKA energy. However, the increase in the number of vacancy clusters with PKA energy is minimal-to-constant and decreases as the irradiation temperature increases. Similarly, the probability and cluster size distribution for larger interstitials increase with temperature, whereas only smaller size vacancy clusters were observed at higher temperatures.

Levels of external natural radiation and doses to population in Heilongjiang province

International Nuclear Information System (INIS)

Liang Yicheng; He Yongjiang; Wang Lu

1985-01-01

The external natural radiation level in Heilongjiang Province was measured by using China-made FD-71 scintillation radiometers and RSS-111 high pressure ionization chambers. The doses of external radiation to population were also calculated. The population-weighted average value of the absorbed dose rate from terrestrial γ-radiation was 7.2 x 10 -8 Gy.h -1 for outdoors, and 10.8 x 10 -8 Gy.h -1 for indoors. The population-weighted average absorbed dose rate in air from cosmic rays was 3.3 x 10 -8 Gy.h -1 . The annual population-weighted average effective dose equivalent and the annual collective effective dose equivalent from the environmental γ-radiation were 620 μSv and 20.1 x 10 3 man.Sv, respectively. The corresponding figures from cosmic rays were 260 μSv and 8.7 x 10 3 man.Sv, respectively

Lower prevalence but similar fitness in a parasitic fungus at higher radiation levels near Chernobyl.

Science.gov (United States)

Aguileta, Gabriela; Badouin, Helene; Hood, Michael E; Møller, Anders P; Le Prieur, Stephanie; Snirc, Alodie; Siguenza, Sophie; Mousseau, Timothy A; Shykoff, Jacqui A; Cuomo, Christina A; Giraud, Tatiana

2016-07-01

Nuclear disasters at Chernobyl and Fukushima provide examples of effects of acute ionizing radiation on mutations that can affect the fitness and distribution of species. Here, we investigated the prevalence of Microbotryum lychnidis-dioicae, a pollinator-transmitted fungal pathogen of plants causing anther-smut disease in Chernobyl, its viability, fertility and karyotype variation, and the accumulation of nonsynonymous mutations in its genome. We collected diseased flowers of Silene latifolia from locations ranging by more than two orders of magnitude in background radiation, from 0.05 to 21.03 μGy/h. Disease prevalence decreased significantly with increasing radiation level, possibly due to lower pollinator abundance and altered pollinator behaviour. Viability and fertility, measured as the budding rate of haploid sporidia following meiosis from the diploid teliospores, did not vary with increasing radiation levels and neither did karyotype overall structure and level of chromosomal size heterozygosity. We sequenced the genomes of twelve samples from Chernobyl and of four samples collected from uncontaminated areas and analysed alignments of 6068 predicted genes, corresponding to 1.04 × 10(7)  base pairs. We found no dose-dependent differences in substitution rates (neither dN, dS, nor dN/dS). Thus, we found no significant evidence of increased deleterious mutation rates at higher levels of background radiation in this plant pathogen. We even found lower levels of nonsynonymous substitution rates in contaminated areas compared to control regions, suggesting that purifying selection was stronger in contaminated than uncontaminated areas. We briefly discuss the possibilities for a mechanistic basis of radio resistance in this nonmelanized fungus. © 2016 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

Systemic effects of ionizing radiation at the proteome and metabolome levels in the blood of cancer patients treated with radiotherapy: the influence of inflammation and radiation toxicity.

Science.gov (United States)

Jelonek, Karol; Pietrowska, Monika; Widlak, Piotr

2017-07-01

Blood is the most common replacement tissue used to study systemic responses of organisms to different types of pathological conditions and environmental insults. Local irradiation during cancer radiotherapy induces whole body responses that can be observed at the blood proteome and metabolome levels. Hence, comparative blood proteomics and metabolomics are emerging approaches used in the discovery of radiation biomarkers. These techniques enable the simultaneous measurement of hundreds of molecules and the identification of sets of components that can discriminate different physiological states of the human body. Radiation-induced changes are affected by the dose and volume of irradiated tissues; hence, the molecular composition of blood is a hypothetical source of biomarkers for dose assessment and the prediction and monitoring of systemic responses to radiation. This review aims to provide a comprehensive overview on the available evidence regarding molecular responses to ionizing radiation detected at the level of the human blood proteome and metabolome. It focuses on patients exposed to radiation during cancer radiotherapy and emphasizes effects related to radiation-induced toxicity and inflammation. Systemic responses to radiation detected at the blood proteome and metabolome levels are primarily related to the intensity of radiation-induced toxicity, including inflammatory responses. Thus, several inflammation-associated molecules can be used to monitor or even predict radiation-induced toxicity. However, these abundant molecular features have a rather limited applicability as universal biomarkers for dose assessment, reflecting the individual predisposition of the immune system and tissue-specific mechanisms involved in radiation-induced damage.

Epidemiological methods of assessing risks from low level occupational exposure to ionising radiation

International Nuclear Information System (INIS)

Reissland, J.A.

1982-01-01

The resolution of radiation-attributable malignancies from the background of malignancies which are responsible for about 20% of all deaths in the Western world, presents a formidable challenge to epidemiological methods. Some of the major difficulties facing those with the task of estimating the risks associated with exposure to low level ionising radiation are discussed, particularly in the context of radiological protection. Some of the studies currently in progress are summarised and suggestions are made for other work which may help to contribute to a better understanding of the quantitative aspects of radiation risk assessment. (author)

Decoding sound level in the marmoset primary auditory cortex.

Science.gov (United States)

Sun, Wensheng; Marongelli, Ellisha N; Watkins, Paul V; Barbour, Dennis L

2017-10-01

Neurons that respond favorably to a particular sound level have been observed throughout the central auditory system, becoming steadily more common at higher processing areas. One theory about the role of these level-tuned or nonmonotonic neurons is the level-invariant encoding of sounds. To investigate this theory, we simulated various subpopulations of neurons by drawing from real primary auditory cortex (A1) neuron responses and surveyed their performance in forming different sound level representations. Pure nonmonotonic subpopulations did not provide the best level-invariant decoding; instead, mixtures of monotonic and nonmonotonic neurons provided the most accurate decoding. For level-fidelity decoding, the inclusion of nonmonotonic neurons slightly improved or did not change decoding accuracy until they constituted a high proportion. These results indicate that nonmonotonic neurons fill an encoding role complementary to, rather than alternate to, monotonic neurons. NEW & NOTEWORTHY Neurons with nonmonotonic rate-level functions are unique to the central auditory system. These level-tuned neurons have been proposed to account for invariant sound perception across sound levels. Through systematic simulations based on real neuron responses, this study shows that neuron populations perform sound encoding optimally when containing both monotonic and nonmonotonic neurons. The results indicate that instead of working independently, nonmonotonic neurons complement the function of monotonic neurons in different sound-encoding contexts. Copyright © 2017 the American Physiological Society.

Radiation and cancer in Wales. The biological consequences of low-level radiation

International Nuclear Information System (INIS)

Busby, C.C.

1994-01-01

It has become increasingly clear in the last ten years that, in the UK, the scientific measurement and appraisal of human health risks, including pollution, are in the hands of the Government and establishment controlled organisations. In the area of drug-related illness, drug side-effects and medicine safety, profits are routinely put before health. The Chernobyl catastrophe, the greatest single pollution event ever, saw the Government responding with warnings which were too little and too late. Water and milk had been drunk, contaminated animals had been sold and eaten. Recently we have come within a hair's breadth of an ozone hole over Europe at a time when a General Election was in progress. Nothing was said: what information that was available came from the United Nations, from NASA, anywhere but from the UK Government. A recently leaked CEGB document shows levels of radioisotopic pollution in the Trawsfynydd lake to be different (and much higher) than those admitted to by Nuclear Electric pic and published by the Welsh Office. Details of the enormous release of radiation to the environment following the Windscale reactor fire in 1957 have only recently become available. At the time people could have been warned but were not. It is no longer possible to believe what we are told. Or what we are not told. Subtle and serious hazards to human health may exist and be unknown to us. To those who read this and perhaps follow up some of the references, it may seem a difficult task to choose between the few heretical voices and the massive nuclear industry megaphone. I have often been asked a variation of the following question: 'If scientists cannot agree amongst themselves on the effects of radiation, how are mere laymen expected to choose in this complicated and difficult area?' And so radiobiology has become like a religion. You believe or you do not. Radiation causes cancer at low dose or it does not. This is not a necessary state of affairs. Enough data is now

Radiation and cancer in Wales. The biological consequences of low-level radiation

Energy Technology Data Exchange (ETDEWEB)

Busby, C C

1994-07-01

It has become increasingly clear in the last ten years that, in the UK, the scientific measurement and appraisal of human health risks, including pollution, are in the hands of the Government and establishment controlled organisations. In the area of drug-related illness, drug side-effects and medicine safety, profits are routinely put before health. The Chernobyl catastrophe, the greatest single pollution event ever, saw the Government responding with warnings which were too little and too late. Water and milk had been drunk, contaminated animals had been sold and eaten. Recently we have come within a hair's breadth of an ozone hole over Europe at a time when a General Election was in progress. Nothing was said: what information that was available came from the United Nations, from NASA, anywhere but from the UK Government. A recently leaked CEGB document shows levels of radioisotopic pollution in the Trawsfynydd lake to be different (and much higher) than those admitted to by Nuclear Electric pic and published by the Welsh Office. Details of the enormous release of radiation to the environment following the Windscale reactor fire in 1957 have only recently become available. At the time people could have been warned but were not. It is no longer possible to believe what we are told. Or what we are not told. Subtle and serious hazards to human health may exist and be unknown to us. To those who read this and perhaps follow up some of the references, it may seem a difficult task to choose between the few heretical voices and the massive nuclear industry megaphone. I have often been asked a variation of the following question: 'If scientists cannot agree amongst themselves on the effects of radiation, how are mere laymen expected to choose in this complicated and difficult area?' And so radiobiology has become like a religion. You believe or you do not. Radiation causes cancer at low dose or it does not. This is not a necessary state of affairs. Enough data is now

Evaluation of the radiation levels in different surgical procedures

International Nuclear Information System (INIS)

Silva Santos, M.C.P. da; Almeida, A. de; Belluci, A.D.; Ghilardi Neto, T.

1989-01-01

The exposure of a medical team to radiation during surgical procedures evidently depends on the duration and difficulties of the particular procedure. We have made a dosimetric study of the average equivalent doses received by the surgical teams during 10 different surgical procedures over a period of one month. Our results demonstrate that the levels of ionizing radiation that the members of the teams receive typically do not surpass the limits stipulated for the following surgical procedures: nefrolithotomy, percutaneous ureterolithomy, ureteroscoy connected with removal of stones in the inferior third of the ureter, osteosynthesis of the tibial plateau together with a articular toalet and minireconstruction of the knee. For compound surgical procedures, for example, osteosynthesis of a femur fracture together with biopsy of an exposed femur or percutaneous nefrolithotomy (complex cases), the dose limits have been surpassed owing to the additional fluoroscopy needed in those p rocedures. (author) [pt

Is the primary event in radiation-induced chronic myelogenous leukemia the induction of the t(9; 22) translocation

Energy Technology Data Exchange (ETDEWEB)

Holmberg, M. (Swedish Radiation Protection Inst., Stockholm (Sweden))

1992-05-18

The probability that ionizing radiation induces a t(9;22) reciprocal translocation with its break points confined to the same regions as the break points for the Philadelphia (Ph') translocation in chronic myelogenous leukemia (CML) has been calculated to be 7 x 10[sup -12] per cell and gray. This figure was used to estimate the number of individuals among the atomic bomb survivors at Hiroshima and Nagasaki with such an induced translocation. For 9196 atomic bomb survivors who received a mean organ dose equivalent to bone marrow of 0.85 sievert, the estimate is done that the number of individuals with a radiation-induced t(9;22) translocation in one of the pluripotent stem cells in bone marrow is of the order of 50. The observed number of affected individuals with CML within the same cohort is 18. Even if the estimate of the number of individuals has relatively large errors, this indicates that the primary event in the radiation-induced CML cases can be a radiation-induced t(9;22) reciprocal translocation. (Author).

Radiation levels and countermeasure research on radiological protection in tin mine in china

International Nuclear Information System (INIS)

Yang Fengfang; Yuan Yongling

2010-01-01

Objective: To study the distribution of radiation level in our nation's tin mine, therefore comes up with proposals on radiological protection and provide scientific evidence on how to protect lives and health of worker underground in tin mine. Methods: To get the radiation level of the underground workplaces in tin mine by analysis of research papers and the measuring results from on-scene investigations. Results: Majority of the absorbed dose rates of γ radiation in the air of underground workplaces in tin mine falls within the range of radiation levels of normal background. Earlier, the typical values of radon concentration and potential alpha energy concentration of radon daughters in the air of underground workplaces in tin mine are 3.12 kBq/m 3 and 5.61 μJ/m 3 respectively. Now, radon concentration and potential alpha energy concentration of radon daughters in the air of underground workplaces in majority of tin mine are lower than 1000 Bq/m 3 and 3.57 μJ/m 3 . Conclusion: For these tin mine workers with an average of annual effective dose greater than 1 mSv or these of their specific activity for natural uranium in materials are greater than 1 Bq/g need to have regulation of radiological protection. The control limits for the radon concentration and the potential alpha energy concentration of radon daughters and the absorbed dose rates of γ radiation in the air of underground workplaces in tin mine are 1000 Bq/m3, 3.57 μJ/m 3 and 1 μGy/h respectively. The administrative individual dose for workers working under the ground of tin mine is 10 mSv/a. If a worker's total annual effective dose is greater than 10 mSv, he/she should be considered as radioactive worker. (authors)

Monitoring of Level of Radiation Hazards to the Community in the Settlement Around the Incandescent Gas Mantle Factory

International Nuclear Information System (INIS)

Suryawati

2000-01-01

The analyze of radiation internal hazards level of thoron (Rn-220) and its daughter to the community settlement around the incandescent gas mantle factory. The radiation hazard level can be indicated in the form of working level (WL) and sffsctive dose lungs received by the community. The working level and effective dose lungs is got from the measurement of radioactivity level of thoron (Rn-220) and its daugther and by using the mathematical formula calculation. The measurement of thoron radioactive concentration and its daughter. The value of woking level obtained, performance level for community range from 0,001-0,013 WL, equivalent with dose range from 0,014- 0,467 mSv. From the research result, it can be identified that the radiation hazard, because exceed the mean value of threshold thorium radioactive nuclide and its daughter product of natural radiation in back ground per year for word mean i.e. 0,336 mSv, but the value of this research result is far below the allowed value limit for the community is 0,12 WL and 1 mSv/year

Process and kinetics of the fundamental radiation-electrochemical reactions in the primary coolant loop of nuclear reactors

International Nuclear Information System (INIS)

Kozomara-Maic, S.

1987-06-01

In spite of the rather broad title of this report, its major part is devoted to the corrosion problems at the RA reactor, i.e. causes and consequences of the reactor shutdown in 1979 and 1982. Some problems of reactor chemistry are pointed out because they are significant for future reactor operation. The final conclusion of this report is that corrosion processes in the primary coolant circuit of the nuclear reactor are specific and that radiation effects cannot be excluded when processes and reaction kinetics are investigated. Knowledge about the kinetics of all the chemical reactions occurring in the primary coolant loop are of crucial significance for safe and economical reactor operation [sr